STUDIES IN ELECTRO-PHYSIOLOGY
STUDIES
ELECTRO-PHYSIOLOGY
(Animal and Vegetable)
By
ARTHUR E. BAINES
CONSULTING ELECTRICIAN
Author of " Electro- Pathology and Therapeutics," etc.
WITH THIRTT-ONE ORIGINAL DRAWINGS
IN COLOUR, ILLUSTRATING THE ELECTRICAL
STRUCTURE OF FRUITS AND VEGETABLES
By
GLADTS T. BAINES
And nun fr ous other I /lustrations
GEORGE ROUTLEDGE SONS, LTD.,
BROADWAY HOUSE, 68-74, CARTER LANE, E.G.
1918
PRINTED IN GRKAT BRITAIN BY THE ANCHOR PRESS LTD. TEPTREE ESSBX.
THIS WORK IS DEDICATED
TO
THE MEDICAL PROFESSION
IN THE HOPE
THAT IT MAY INTEREST AND INSTRUCT, AND
PAVE THE WAY
TO
FRESH CLINICAL ADVANCE
ALONG
THE LINES HEREIN
SUGGESTED
PREFACE
I HAVE been encouraged by several medical friends, and
particularly by my fellow students, Drs. White Robertson
and E. W. Martin, to make an excursion into the realm of
Electro-physiology ; a subject which I had previously been
reluctant to take up in the declining years of my life owing
to the controversy which any new view of the operating
forces of the body would be sure to provoke. But the
matter at issue is too important for personal considerations
to outweigh a possible advance in knowledge.
For more than half a century theories which were
without any real scientific basis have barred the way to
progress, and the rebutting evidence hitherto at command
was in itself insufficient to compel adequate attention,
although it was, upon careful examination, enough to refute
the theories in question.
In a former work* of an unambitious character I
considered the nature and distribution of nerve force from
a new standpoint, and it followed that if I had discovered
a fundamental principle my research work must harmonise
with established laws and enable me, in accordance with
those laws, to explain not only the nature and source of
the force but to show how by its means the various func-
tions of the body were called into operation.
The two theories of the nature of the nerve' impulse,
the physiological and the physical, are, in the present state
of our acquaintance with the subject, equally unsatisfac-
tory; but it has always been clear to my mind that upon
investigation the body structure should make it manifest
whether it was primarily designed for electrical or chemical
functions ; or rather, whether it was evident from its
* Electro-Pathology and Therapeutics.
vii
viii PREFACE
structure that electrical action was precedent to chemical
change. If not, if, on the contrary, the body consisted of
a congeries of chemical laboratories, with only an oc-
casional suggestion of an electrical circuit, then I was
self-deceived.
To this day we electricians do not know if in a galvanic
cell electrical begets chemical action or vice versa. But in
the form and appearance of a galvanic cell there is nothing
to guide us to definite opinion, much less to afford con-
clusive proof. What is electricity ? There are the one-
fluid and two-fluid theories. Dr. Le Bon has found that
the particles emitted from an electrified point are identical
with those of radium ; carbon when suitably treated will
give off a form of energy resembling electricity but which
can be shown to be some other element if electricity is an
element. We talk glibly of ions and electrons although
we know very little about them and are constantly
advancing new theories as if they were laws, and endeavour-
ing, and failing, to make results agree with them. There
is only one law, and upon that law all creation is founded ;
one law for the living and a modification of it for the dead.
There are, of course, differences of structure and perfection
of structure, but the same law, as I hope to show in these
pages, governs without exception everything that lives
upon this earth, animal and vegetable alike.
A. E. BAINES.
London, 1918.
ERRATA
Page 34 ; line 5. For " Separates it " read " Separates the
foliage."
Page 57 ; line 1. For " 2,000 " and " 40 " read " 200 "
and " 400."
Page 95 ; line 2. For " 15 and 5 " read " 5 and 15."
Page 98 ; line 5. For " points are " read " points is."
Page 119 ; fig. 31. For " controsphere " read " centro-
sphere."
Page 143 ; line 29. For " Gynostemium " read " Gymnos-
temium."
Page 169 ; line 20. For " SO 4 " read " SO 8 ."
Page 172. Inverted commas should commence on line
80, after " subject."
Page 173 ; line 20. For " to the lower thigh-bone " read
" to the leg bone." Line 28 : For " upper and lower thigh-
bones " read " upper and lower bones."
PART II
STUDIES IN ELECTRO-PHYSIOLOGY:
REVIEW OF ELECTRO-PHYSIOLOGICAL RESEARCH 49
CAUSES WHICH HAVE CONTRIBUTED TO ERROR 54
THE NATURE OF THE NERVE IMPULSE - - 73
INDUCTIVE CAPACITY - - 91
CELL REPRODUCTION - - 108
ix
viii PREFACE
structure that electrical action was precedent to chemical
change. If not, if, on the contrary, the body consisted of
a congeries of chemical laboratories, with only an oc-
casional suggestion of an electrical circuit, then I was
self -deceived
To this d
cell electrica
the form anc
to guide us
elusive proo
fluid and tw
the particles
with those c
give off a fo
can be show
element. \^
we know \
advancing n<
ing, and fail
is only one 1
one law for 1
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of structure,
pages, gove
upon this ea
London, 191'
TABLE OF CONTENTS
PAGE
PREFACE - - vii
INTRODUCTION V - - - - xxv
PART I
ELECTRICAL STRUCTURE AND FUNCTION
IN PLANT LIFE:
GENERAL 3
DO VEGETABLES AND FRUITS POSSESS CAPACITY ? 17
SOME SEEDS IN THEIR ELECTRICAL ASPECT - 22
THE ELECTRODES AND ELECTROLYSIS - - 35
PRIMARY OR SECONDARY CELLS ? - 36
WATER IN ITS RELATION TO PLANT LIFE - 38
THE EFFECT OF ELECTRICAL STIMULATION
UPON GROWTH - 39
THE EMPLOYMENT OF ELECTRICITY IN AGRI-
CULTURE - 42
NOTE FOR GUIDANCE IN TESTING - 44
PART II
STUDIES IN ELECTRO-PHYSIOLOGY:
REVIEW OF ELECTRO-PHYSIOLOGICAL RESEARCH 49
CAUSES WHICH HAVE CONTRIBUTED TO ERROR 54
THE NATURE OF THE NERVE IMPULSE - - 73
INDUCTIVE CAPACITY - -^ 91
CELL REPRODUCTION - - 108
ix
x TABLE OF CONTENTS
PART II. Continued.
PAGE
SEGMENTATION OF THE OVUM - 110
ANIMAL MAGNETISM - - 116
SOME EVIDENCES OF THE LAW - 118
AMOEBOID MOVEMENT - - 138
STRIATED MUSCULAR TISSUE - - 144
SARCOLEMMA AND NEURILEMMA - 161
OTHER INSULATING PROCESSES - 161
TERMINATION OF NERVES IN MUSCLE - - 165
DENDRONS AND SYNAPSES - 168
CONNECTION OF MUSCLES AND BONES - 172
RESPONSE OF MUSCLES AND NERVES TO ELEC-
TRICAL STIMULATION - 178
CARDIAC MUSCLE - 182
PLAIN MUSCLE - 184
NISSL'S GRANULES - 189
THE NODES OF RANVIER 192
GANGLION CELLS - 196
UNIPOLAR AND BIPOLAR CELLS - 203
MULTIPOLAR CELLS - - 205
THE EYE - 217
THE EAR - 228
ELECTRO-DIAGNOSIS - - 234
OHM'S LAW - 245
THE INTERPRETATION OF CERTAIN ELECTRO-
PHYSIOLOGICAL PHENOMENA - 251
APPENDIX :
ELECTRICAL CONDITIONS OF THE EARTH - 267
ELECTRICITY IN RELATION TO SOME VEGETABLE
POISONS ..... 277
LIST OF ILLUSTRATIONS
PART I In Colour
ELECTRICAL STRUCTURE AND FUNCTION IN
PLANT LIFE
Plate I-II. Apple . r .
. face p. 10
Plate III-IV. Banana >^',.v . . *
, face p. 11
Plate V. Tomato ^ . . .
. face p. 10
Plate VI. Orange . .;'.,.
. face p. 10
Plate VII- VIII. Lemon . . .
. face p. 11
Plate IX-XI. Turnip . . .;\, .
. face p. 12
Plate XII. Carrot
. face p. 13
Plate XIII. Onion .
< face p. 13
Plate XIV-XV. Potato ,1
. face p. 14
Plate XVI-XVII. Artichoke
. face p. 15
Plate XVIII. Horse-Chestnut Leaf . .
. face p. 16
Plate XIX. Ivy Leaf .
. face p. 16
Plate XX. Onion . . .V
. face p. 17
Plate XXI. Onion -'..,. . ,
. face p. 17
Fig. 21a. Diagram of Connections (not Coloured)
p. 18
PART I Black and White
FIG.
PAGE
22. Section of Horse-Chestnut . ._ -. ,
4 . 23
23. Section of Horse-Chestnut .
.24
24. Showing how Induction takes place . . ,
. .. . 25
25. Section of Horse-Chestnut Seed . fc *
. . 26
26. Horse-Chestnut Seed . . ;V -,
'* . 26
27. Sections of Horse-Chestnut Seed . . ?*u
: ^;,, . 27
28. Section of Edible Chestnut . .
- V . 30
29. Section of Edible Chestnut . ' .
. 30
30. Acorns .....
. 32
31. Double Acorn in Section
. 33
32. Cluster of Cob-Nuts ....
. 34
33. Foliage and Cup of Cob-Nut opened out
. 34
xi
xii LIST OF ILLUSTRATIONS
PART II Black and White
PAGE
1. Thumbjpressure upon Electrodes
2. Condenser ..... .02
8. Conventional Drawings of Condenser . . . .92
4. Conventional Drawings of Condenser . . . .9,3
5. Condenser joined up with Battery . .93
6. Condensers in Parallel . . . . . .93
7. Condensers in Series . ' . . . . .94
8. Condensers in Series 4 '... . .94
9. Condensers in Series v * . ' . . . 95
10. Condensers in Series . . . ' V ' . .96
11. Suggested Connection of Endplates with Muscle . 100
12. Diagram of Connections for Capacity Test . V . 102
13-20. Illustrating Mitotic Division . . ." 104-108
21-22. Illustrating Segmentation of the Ovum . . . Ill
23. Illustrating Cell Division . *" . . .- ' .116
24. Lines of Force of Bar Magnet . . ... 117
25. Lines of Force of Two Bar Magnets . . . .117
26-33. Illustrating Phases in Cell Reproduction in Animal and Plant
118-119
34. Fertilisation of the Ovum of a Mammal ; . .119
35. Oosphere with Spermatozoids TO . . . .119
36. Ganglion Cell (Human) . . . .120
37. Spore of Vaucheria Sessilis . . . , . . .120
38. Section of Spinal Cord (Human) . , . .120
39. Transverse Section through a Root . . . .120
40. Unipolar Cell of Rabbit . . . . .121
41. Section of a Branch of Usnea Barbata . -. : ; >. . 121
42. Fibrils in the Sheath of a Nerve-Fibre . y , . . 121
48. Cells from a Leaf of Hoya Carnosa . . . .121
44. Formation of Blastoderm in Rabbit . . . .122
45. Division of Pollen Mother Cells of Plant . . .122
46. Group of Cartilage Cells . . . . .122
47. Division of Pollen Mother Cells of Plant . . .122
48. Transverse Section of Sciatic Nerve of Cat . . .122
49. Parenchyma Cell from Cotyledon of Plant . . .122
50. Fibro-Cartilage Cells . . . . . .123
51. Cells from Cortical Tissue of the Stem of a Plant . . 123
52. Section of Salivary Gland (Human) . . . ' . 123
53. Glandular Colleter of Plant . . . . .123
54. Muscular Fibre-Cell (Human) . . . . .123
55. A Vegetable Fibre . . . . . .128
LIST OF ILLUSTRATIONS xiii
PART II Black and White. Continued.
FIG. PAGE
56. Diagram of Pregnant Human Womb .... 124
57. Ovule of a Gymnosperm . ..... 124
58. Epithelium Cells (Human) . . . . V . 124
59. Peripheral Protoplasm of the Embryo Sac of Plant . . 124
60. Endothelium of a Serous Membrane (Human) . . . 125
61. Cells from a Tendril of a Plant . , ,\ . . 125
62. Section across a Nerve Bundle (Dog) . . . . 125
63. Section through a Young Internode of Plant . . .125
64. Capillary Vessels of the Air Cells of Lung (Horse) . . 126
65. Laticiferous Vessels from Root of a Plant . . . 126
66. Injected Blood-Vessels of Muscle (Human) . . . 127
67. United Latex Vessels of Plant . . . . . c 127
68. Stomata in Different Stages of Opening and Closing . . 129
69. Cells from the Leaf of a Plant ..... 134
70. Cells from a Staminal Hair of a Plant .... 134
71. Electrical Diagram of Voluntary Muscular Fibre . .147
72. Physiological Diagram of Voluntary Muscular Fibre . . 148
73. Electrical Diagram of Voluntary Muscular Fibre . . 148
74-76. Illustrating Expansion and Contraction of Muscle . . 149
77. Diagrammatic . ...... 150
78. Connection of Nerve with Muscle . . . .150
79. Connection of Nerve with Muscle . . . .151
80. Connection of Nerve with Muscle . . . .151
81. Sarcomere in Moderate Extension . . . .151
82. Sarcomere in Contracted Condition .... 152
83. Portion of Leg Muscle of Insect .... 153
84. Muscle Curve . . . . . . .160
85. Section of Sciatic Nerve of Cat .... 162
86. Section of Screened Cable ..... 163
87. Termination of Nerve-Fibre in Tendon .... 165
88. Plexus of Auerbach . . . . . .167
89. Illustrating Molecular Theory of Electricity . . .169
90. Synaptic Connections of a Sympathetic Cell . . .170
91-91A. A Synapse (Diagrammatic) . . .- . 170-171
92. A Synapse (Diagrammatic) . . . . . 171
93-94. Illustrating the Parallelogram of Forces . , . 176
95. Muscular Fibre Cell (Small Intestine) - . .184
96-99. Illustrating Contraction of Same (Diagrammatic) . .186
100. Muscle Cells of Intestine . . . . 187
101. Anterior Horn Cell with Processes . . . .190
xiv LIST OF ILLUSTRATIONS
PART II Black and White. Continued.
Fio. PAGE
102. Showing a Node of Ranvier ..... 192
103. Showing a Node of Bamboo . . . . .193
104. Degeneration of Nerve to Node of Ranvier . . .194
105. Diagram of Chain of the Sympathetic . . .197
106. Neurons of the Motor Path (Physiological) . . .199
107. The same reproduced artificially .... 199
108. Forms of Spinal Ganglion-Cells .... 200
109. A Unipolar Cell (Rabbit) ^ .' . . .205
110. A Bipolar Cell (Fish) ; -. . . .205
111. Sketch of Metallic Ball for Electrification ""- " . . 206
112. A Multipolar Cell (Physiological) . ^ . . 208
113. A Multipolar Cell (Electrical) . .- jj& . 208
114. A Multipolar Cell (Electrical) . .- ]V . 209
115. A Multipolar Cell (Fish) .... . . . . 211
116. Reflex Action . ^. . . . . 212
117. Root Fibres of the Cranial Nerves . . - . .214
118. Plan of the Origin of the Fifth Nerve . , .215
119. Pigmented Cells of the Retina . . v'* . 221
120. Section through the Human Eye , . \ .224
121. Section through the Macula Lutea and Fovea . . . 225
122. Diagrammatic Section of the Human Retina . . \ 225
123. Scheme of the Organ of Hearing . . '.. . . 229
124. Square Case Kelvin Reflecting Astatic Galvanometer . . 235
125. Milled Torsion Head . . . , . .236
126. A d'Arsonval Galvanometer . . . . y . 238
127. Galvanometer Scale and Lamp . . . , . 239
128. Transparent Galvanometer Scale and Stand . . . 240
129. Paraffin Lamp for use with Galvanometer . . . 240
130-131. Diaphragms -. ; . >^ y 4 . . 241
182-133. Short-Circuit Keys . . . . .241
184. Electrode ....... 242
185. Thumb-Piece . . . . . .243
136. Method of Connecting . . . . 248
187-138. Electrodes . . . . . 248-4
189-140. Diagrams illustrating Ohm's Law .... 248
141-142. Diagrams of Fall of Potential . . . .258
143. Illustrating Deflection in Lobar Pneumonia . . . 255
143A-143C. Differences of Level and Potential . . 256-7
144-146. Illustrating Earth and Cloud . . . .268-9
SYNOPSIS OF PART I
ELECTRICAL STRUCTURE AND FUNCTION IN
PLANT LIFE
CHAPTER I
GENERAL
PAGE
Application of electricity to the soil No attempt to ascertain
Nature's methods Experiments not conclusive The views
of Thome and Sachs Analogies in animal and vegetable
physiology Electricity plays a part in the vegetable as well as
in the animal world Everything living has a well-defined
electrical system The edible part of a fruit or vegetable is the
positive element Dry earth is a non-conductor of electricity
Water required as an electrolyte Conservation of energy of
vegetable cells Electromotive force of vegetables, plants and
fruits Plants grown in pots Electrical stimulation of growth
The recording instrument and electrodes Sign of the earth
and the air How earth-grown plants, etc., are charged
Method of testing described Theories examined and disputed
Effect of diffusion or decay The apple described and illustrated
How a cut apple endeavours to protect itself against decay
The banana illustrated, its positive and negative systems The
tomato illustrated Difference between one grown in the open
and one from the greenhouse Effect of connecting pot with the
earth The orange and lemon, illustrated and described-
Peculiarity of absolute insulation The turnip illustrated
Defective absolute insulation and consequent short life after
removal from the soil No adequate means of protection
Effect of keeping in a moist condition (illustrated) The carrot,
illustrated and described The onion (illustrated), a compound
cell Difficult to examine galvanometrically rPerfect absolute
insulation Its electromotive force and current- Invaluable as
a standard cell - - . r v . 8
Tubers : The potato, illustrated and described Takes its current
from the mother plant Prolific and unprolific eyes How it is
enabled to repair injury How it grows (illustrated) The
Jerusalem artichoke (illustrated) Takes its electrical supply
directly from the earth and differs in other respects from the
potato Leaves Deciduous and evergreen Differences of in-
sulation and life The horse-chestnut and ivy (illustrated) - 14
XV
xvi SYNOPSIS
PAQE
Do Vegetables and Fruits possess Capacity ? Answer in the affirma-
tive Experiment with a quince How the tests were taken
Experiments with onion, rhubarb, apple, banana, turnip and
orange described - 17
CHAPTER II
SOME SEEDS IN THEIR ELECTRICAL ASPECT
Examination of seeds, in their various stages of development, of
great interest Some analogy between some immature seeds
and the human foetus Some law seems to govern both and also
cell-reproduction The HORSE-CHESTNUT seed illustrated
Method of preparation and testing Its construction, electrically
considered The insulating membranes and conducting layer
How the seed-pod is charged by the earth and the air Its
influence upon the seed substance Independent existence of
the seed only begun when it falls from the pod Changes which
then take place and how the seed-substance receives charge
(illustrated) The final appearance of the insulating membranes
(illustrated) The secretion of the pod and seed-substance
Chemical composition of the membranes A contrast The
EDIBLE CHESTNUT (illustrated) examined and tested How
different to the horse-chestnut Weird suggestion of foetus in
womb Higher order of growth Food as well as seed How it
is equipped to serve as both Its capacity compared with that
of the horse-chestnut Hypothetical explanation of the purpose
underlying it The ACORN (illustrated) How the seeds are
joined up electrically The contacts and insulation Twin
seeds and how they are given protection Cob-nuts (illustrated)
How joined up electrically and how insulation is preserved, etc. 22
The Electrodes and Electrolysis : Experiments to determine the
effect of electrolysis upon the deflections observed - - 85
Primary or Secondary Cells ? Probably neither Cells undergo no
disintegration and no change Cannot be polarised or discharged
Length of life in direct ratio to absolute insulation Effect of
short-circuiting Plants " resting " in late autumn, winter and
spring Constancy of vegetable cells Theoretical explanation
of their long-sustained electrical activity - 36
Water in its relation to Plant Life : As dry earth is a non-conductor
of electricity water is also required as an electrolyte Experi-
ment with mustard and cress, ferro-sulphate and less water
Some suggestions - 38
SYNOPSIS xvii
PAGE
The Effect of Electrical Stimulation upon Growth : Currents artificially
sent through a root said to retard growth Statement not
warranted by fact Experiments with potatoes, with plants in
greenhouse, and with onions Question of polarity, not
electricity Variously stimulated onions illustrated - 39
CHAPTER III
THE EMPLOYMENT OF ELECTRICITY IN AGRICULTURE
Review of the last one hundred and fifty years Results considered
Chlorosis in plants Iron and oxygen in plant life Periods of
drought The savoy cabbage - - - "*. - 42
Note for Guidance in Testing : The electrodes and how to connect
them (illustrated) - - - - - -44
SYNOPSIS OF PART II
STUDIES IN ELECTRO-PHYSIOLOGY : ANIMAL
AND VEGETABLE
CHAPTER IV
REVIEW OF ELECTRO-PHYSIOLOGICAL RESEARCH
Present state of knowledge Galvani, Volta, Humboldt, Aldini,
Nobili, Matteucci, Du Bois-Reymond, Radcliffe, Trowbridge
Causes of confusion Certain factors not discovered - - 49
Causes which have Contributed to Error : Generation and dissipation
of nerve force Insulation of the body Air and earth
Individuals differ electrically Conflicting results and the
reason therefor Personal capacity Capacity of liquids and
moist substances Non-polarisable electrodes Other electrodes
and their reliability Dr. Longridge's experiments Dr. Martin's
experiments Other tests of electrodes Argument " Sugges-
tion " The hand-to-hand deflection and thumb-pressure
Structure of the body primarily electrical - - - 54
CHAPTER V
THE NATURE OF THE NERVE IMPULSE
Rival theories, physiological and physical Argument that impulse
is chemical more in favour of it being electrical Argument
Professor Rosenthal and peripheric nerves Inhibition Velocity
b
xviii SYNOPSIS
PAGK
of impulses compared Retardation Resistance of copper
wire compared with nerve Normal E.M.F. and current of
man Effect of capacity Hypothesis of Dr. Martin Natural
dielectrics Experiments of Dr. Le Bon - 73
CHAPTER VI
INDUCTIVE CAPACITY
The effects of capacity Apparent velocity of current diminished
Condenser described Connections in parallel and in series
Joint capacity in series Current and resistance Potential
differences Connection in series-parallel Condensers of the
human body Reflex action Rates of discharge Condenser
action in cardiac muscle Influence of capacity upon velocity of
the nerve impulse Specific inductive capacity Dimensions of
plain and voluntary muscular fibres To test the human body
for capacity, method and diagram - - 9:
CHAPTER VII
CELL REPRODUCTION
Mitotic division The centrosome and the attraction sphere The
centriole Division of cell preceded by division of the attraction
sphere Changes in the cell during the process Achromatic
fibres and spindle Chromatin Chromosomes Irritability of
protoplasm Cleavage Repulsion as well as attraction
Nucleus and nucleolus Division briefly described * - 103
Segmentation of the Ovum : Hetero and homotypical mitosis
Polar bodies Varying number of chromosomes Sperm and
germ nuclei Fertilisation Ascaris megalocephala Difference
from ordinary mitosis Sexual reproduction in plant life
Mucor and spirogyra Fucus Asexual reproduction Fungi,
diatomaeetc and protozoa Importance of nuclei Network in
protoplasm Enzyme action Vines' description of Karyo-
kinesis - - 110
CHAPTER VIII
ANIMAL MAGNETISM
Alleged magnetic influences in the human body Not warranted by
fact Resemblance of certain phenomena to magnetic control
superficial Geddes and Thomson's diagram of cell-division
compared with lines of force of a bar magnet, and with two bar
magnets - 116
SYNOPSIS xix
CHAPTER IX
SOME EVIDENCES OF THE LAW
PAGE
Phases of cell reproduction, animal and vegetable Fertilisation of
the ovum and oosphere Ganglion cell and spore Spinal cord
and root of Phaseolus multiflorus Unipolar cell and section of
branch Spinal and reticular fibrils (human) and cells from a
leaf Blastoderm of rabbit and pollen mother cells of plants
Cartilage and pollen cells Section of sciatic nerve and cell of
plant Fibro-cartilage cells and thickened cells from stem of
plant Human and vegetable glands Cell of plain muscular
fibre and a vegetable fibre Pregnant human womb and ovule
of a gymnosperm Epithelium cells (human) and peripheral
protoplasm of embryo-sac of a plant Endothelium of a serous
membrane (human) and cells from a tendril of a plant Section
across a nerve in the second thoracic anterior root of a dog and
section through internode of the short axis of a plant Capillary
vessels of the air-cells of horse's lung and laticiferous vessels of a
plant Sachs and others upon laticiferous vessels in plants
Injected blood-vessels of a human muscle and reticulately
united latex vessels of a plant Irritability of vegetable proto-
plasm Similarity of senses Motor mechanism of plants
Stomata Stimulation Sense organs of plants Specific
energies of the sensory nerves Enzymes Fats in plants
Wax in plants and fruits Movement or circulation of proto-
plasm in plants Cells from leaf of Elodea and hair of Trades-
cantia Rhythmic movement in plants Paralysis or destruc-
tion of protoplasmic movement Rate of propagation of
stimuli in plants - - 118
CHAPTER X
AMCEBOID MOVEMENT
Movement apparently spontaneous Nucleo-protein All breathing
or taking in oxygen Nature of the movement Effect of
change of temperature, chemical stimuli, electrical stimuli, etc.
Foregoing paraphrased and explained Live and dead
amoeba The experiment of Ampere Attraction and repulsion
Experiments of Davy, Le Bon and Arrhenius Czapec on
salt solutions Inorganic salts in the blood plasma Rigor or
cessation of protoplasmic movement in plants - - - 138
CHAPTER XI
ELECTRO-PHYSIOLOGY OF THE MOTOR APPARATUS
Muscular tissue Striated muscular tissue Anticipation before
study Sarcolemma and structure of the sarcomeres Krause's
membranes or Dobie's lines Chemical or electrical action ?
xx SYNOPSIS
Certain electrical laws Physiological and electrical diagrams
Artificial muscular fibre Discharge or neutralisation of charge
Further diagrams How the nerve-fibres connect with groups
of sarcomeres Muscle extended and contracted The plane of
Hensen Condenser-action The " Muscle Telegraph " of Du
Bois-Reymond Physiology of muscular fibre considered
Stimuli not various forms of energy Clear spaces may be
" points " Stimuli not discharging forces Effect of rise or
fall of temperature upon muscular fibre Excised muscle
Difference between the living and the non-living Comparison
with frog, toad and tortoise Excitability of muscle when nerve
dead Compared with apple Independent muscular activity
reviewed Wrong to say plants have no nerves Reasons
therefor Effect of poisons upon nerves and plants Curara
and nux vomica Muscle-curve due to single induction shock
examined - - 144
Sarcolemma and Neurilemma : Both elastic and both dielectric in
character Argument ^ -161
Other Insulating Processes : Sciatic nerve of cat Endoneurium,
perineurium and epineurium-^The electrical function of lymph
Insulation of submarine and screened land cable Inductive
interference - - - 161
The Termination of Nerves in Muscle : End -organs Fibres branch
Medullated nerve-fibres Plexuses of involuntary muscle
Each nerve-fibre separately insulated Plexus of Auerbach - 165
Dendrons and Synapses : Cells of Purkinje Neuroglia and con-
nective tissue Dendrons, axon and neuron Cell processes
Synaptic junctions Contiguous but not continuous structures
Propagation of electric force by molecular action Sympathetic
cell : arborisations Physiological path of chains of neurons
uninterrupted Synapse compared with condenser Necessity
for insulating processes in the body .... 168
Connection of Muscles and Bones : Whole action of muscle the sum
of the separate actions of all the fibres Fan-shaped muscles
Semi-pennate muscles Pennate muscles Parallelogram of
forces Work performed by muscles conditioned by their
attachment to the bones Sesamoid bones - - 172
Response of Muscles and Nerves to Electrical Stimulation : Nutrition
of the nerves When impaired Nerve degeneration and its
effect on muscle Changes in the excitability of muscle Con-
tractions caused by constant and induced currents Degenera-
tion of irotor nerve Response of muscle to constant current
Muscular paralysis Paralysis due to disease .- 178
SYNOPSIS xxi
CHAPTER XII
CARDIAC MUSCLE
PAGE
Histological diagrams not sufficiently clear Cardiac muscle inter-
mediate Each segment considered as a sarcomere Branch or
shunt circuits Regulation exercised by the cardiac branches of
the vagi Day and night intake of oxygen in relation to the
hand-to-hand galvanometric deflection Inhibition Effect of
an escape of nerve energy, and of certain toxins - 182
Plain Muscle : Very little information Must be transversely striated
Professor Rosenthal's views Schafer The question of a
sarcolemma Longitudinal striation would only cause flattening
Explanatory diagrams and speculative explanation How the
cells are probably connected up - - - 184
CHAPTER XIII
NISSL'S GRANULES
Cells contain organically combined iron, but not in masses as hitherto
thought -Mott's researches with living cells Nissl's granules
the result of coagulation in the dead cell In the living cell they
exist in the form of fine particles - 189
CHAPTER XIV
THE NODES OF RANVIER
Illustration of a typical node How the nodes occur Compared with
bamboo and canes Strasburger on the nodes of bamboo
Degeneration of nerve only to node Uninterrupted continuation
of axon questioned Constriction and increased resistance
suggested Reasons therefor - - - 192
CHAPTER XV
GANGLION CELLS
Some said to be condensers and some storage cells Differentiation
of the two Efferent and afferent impulses, and control and
regularity of supply Diagram of motor and sensory paths
from spinal cord The functions of a condenser in telegraphy
Diagram of unipolar and bipolar cells Maintenance of normal
insulation resistance Physiological and electrical diagrams of
motor and sensory paths Quantity and tension The views of
Dr. Le Bon Confusion of terms Electro-cardiograms and
ganglia Thornton's views Autonomic ganglia Afferent and
efferent fibres - - - - - - - 196
xxii SYNOPSIS
I'AOB
Unipolar and Bipolar Cells : The conducting and non-conducting
cell-substances Macallum and Turner Forms of Leyden jar
and condenser Their probable connection Cells disposed in
aggregations of different size The capsule of connective tissue
Continuous with the epineurium and perineurium Branching
of the axis-cylinder process at node of Ranvier Neuro-fibril
network within cell body Every cell not of same structure
Illustrations from Schafer - 203
Multipolar Cells : Cells of the cerebral cortex and spinal cord
Construction of an artificial multipolar cell described Surface
area and tension Physiological and electrical diagrams
Dendrons said to be branch circuits How to take off efferent
and afferent impulses at will Arrangement of condensers or
bipolar cells described and illustrated Multipolar cell made up
of as many Leyden jars or rings as there are dendrons with
separate nerve-fibres to each Illustration from Haeckel
Reflex action illustrated and discussed Synaptic junctions
Undifferentiated interstitial protoplasm Storage cells in
sensory paths illustrated Not found in motor paths Con-
nection of voluntary motor fibres with multipolar nerve-cells of
the anterior cornu Direct motor impulses not interrupted in
their passage through the brain - 205
CHAPTER XVI
THE EYE AND THE EAR
The Eye : Strongly suggestive of a compound selenium-cell transmit-
ting apparatus The effect of light upon selenium Transmitting
pictures to a distance The telectroscope described Property
of selenium Transmission of colour Colour in relation to
white light The lens of the eye The iris or diaphragm
Pigment cells illustrated and described The rods and cones
Connections at the fovea and elsewhere The macula lutea
Visual impulses said to begin in the rods and cones on the outer
side of the retina Latter connected functionally, if not struc-
turally, with the nerve filaments that pass to the optic nerve
" Visual purple " Possible function of the epithelial pigment
cells of the retina Our ignorance of how undulations of light
become converted into nervous impulses Ordinary light and
vibrations The eye illustrated Vertical section through the
macula lutea Diagrammatic section of the retina Alleged
vibrations of electrons in the retina Maxwell and the speed of
electro-magnetic waves Duration of the sensation produced by
a luminous impression on the retina Optic nerve said to be a
closed circuit Movement of the pigment cells Movement of
the cones and possibly of the rods - 217
SYNOPSIS xxiii
PAGE
The Ear : Physiological description Endolymph and perilymph
Passage of the impulses The external auditory meatus
Malleus, incus and stapes illustrated and described Mechanical
impulse questioned Mechanism of hearing far from being
satisfactorily settled Neuro-electrical theory more reasonable
and probable than chemical or mechanical Proof that it is so
The fenestra ovalis Basilar membrane and membrane of
Reissner Ear, from external auditory meatus to brain, said to
be a telephone system Auditory nerves closed circuits
" Faults " and how to test for them v - 228
CHAPTER XVII
ELECTRO-DIAGNOSIS THE GALVANOMETER AND
ELECTRODES
Chief requirements in a galvanometer Its required sensibility and
period Illustration of square case Kelvin Its adjustment
Its advantages and drawbacks Galvanometers of the d'Arson-
val type illustrated Scales illustrated The lamp (illustrated)
Types of galvanometer short-circuit keys Shunts Connecting
wires Earth connection The electrodes illustrated and de-
scribed Sign of current unimportant All deflections
comparative - - - 234
CHAPTER XVIII
OHM'S LAW
In its application to the human body Shortly described In terms
of hydrostatics Further description Resistance of metallic and
liquid conductors Fluctuation of human E.M.F. Influence of
capacity of condenser-ganglion cells Variation of potential
Temperature and moisture Diagrams Potential differences - 245
The Hand-to-Hand Deflection : Precautions necessary - 249
Application of Ohm's Law to Solutions : The researches of Arrhenius - 250
CHAPTER XIX
INTERPRETATION OF CERTAIN ELECTRO-PHYSIOLOGICAL
PHENOMENA
Dielectric substances and structures in the human body Effect of
heat upon all known dielectrics Formula for calculating the
relative resistance of gutta-percha Local temperature and
local pyrexia and the effect upon local insulation resistance
Maxwell's experiments Heat and liquid conductors Effect of
heat upon the dielectrics of the body as compared with its effect
xxiv SYNOPSIS
PAGF.
upon gutta-percha Heat and protoplasm Fault in a sub-
marine telegraph cable compared with similar fault in the body
Path of least resistance Lobar pneumonia Exact location
of fault Double pneumonia Varying conditions of contact
and moisture Differences of potential and differences of level
Deflections from hot, dry skin Nervous weakness Impaired
conductivity : effect of certain toxins upon nerve conductivity
Various " faults " Importance of the galvanometer in obscure
morbid pathology Efferent and afferent branches of the vagi - 251
Galvanometric Tests of Other Diseases : Disease in general
Neurasthenia nervous instability as well as nervous weakness
Epilepsy, its distinguishing features and symptoms Suggested
means of alleviation by shunting the nerve current Direct
cause of fit Cancer, some tests of Cancer cells non-conducting
Usefulness of galvanometer in defining area affected - - 260
APPENDIX
ELECTRICAL CONDITIONS OF THE EARTH
The influence of electrified railways, tubes and tram-lines Earth
conditions during thunderstorms Earth and cloud in electrical
relation Lightning and its path through the atmosphere
How the body may be influenced The earth as zero The
earth electrically " patchy " The Rio Plata and mouths of
rivers Earthquakes and thunderstorms in the tropics No
definite knowledge of the causes which set up earth-currents
The aurora borealis Atmospheric electricity Fulminic matter
Thermal origin of earth-currents considered The distribution
of volcanoes Uncertainty as to their condition Earth-current
in the far North Dry or dielectric soils and their possible effect
upon the atmosphere and health, as compared with conductive
soils The torrid, temperate, and frigid zones Atmosphere as a
vitalising agent - 267
ELECTRICITY IN RELATION TO SOME VEGETABLE POISONS
Rhubarb and other leaves Vegetable poisons and dietary The
negative parts of plants, tobacco and tea-leaves Suggested
experiments - 277
BIBLIOGRAPHY - - 280
INTRODUCTORY
RECEIVING a first education in telegraphy in the Post
Office under my uncle, F. E. Baines, C.B., First Surveyor-
General of Telegraphs, and Mr. (afterwards Sir) Wni.
Preece, I joined the service of the Eastern Telegraph
Company in the early seventies, and as the story of how I
became interested in electro-physiological research may
not be without interest, some personal details are perhaps
admissible.
Much about the time of which I am writing I was chief
assistant electrician under my old friend Professor
Andrew Jamieson of the cable-ship The John Fender, be-
longing to the Eastern Telegraph Company and then
engaged in repair work in the Red Sea and Indian Ocean.
An unfortunate accident to my chief left me for a time
in charge, and I had as one of my juniors for a brief period
A. E. Kennelly, now Professor of Electrical Engineering
at Harvard University.
Submarine cables, however, are not always breaking
down, and during an idle interval in the year, so far as my
recollection serves me, 1880, my employers lent me to
Mr. Finlay, of the Cape Observatory, to assist him in
correcting longitudinal data by means of time signals
transmitted over the company's cables between Aden and
Durban.
It was necessary to receive signals upon a reflecting
xxv
xxvi INTRODUCTORY
mirror instrument while listening to the loud ticking of the
seconds of a clock specially made for astronomical work.
The signal had to be sent from one end and recorded at
the other at the exact tick, and Mr. Finlay showed me the
importance of determining my personal coefficient of
error in reading in order that allowance might be made
for it.
Some time afterwards, while engaged in cable-testing
at Delagoa Bay, I noticed a deflection upon the scale of
the Astatic reflecting galvanometer for which I could not
account, and upon investigation found the disturbing
influence to proceed from my own body. This led to a
series of experiments which convinced me that a force
resembling electricity, if not identical with it, was con-
stantly generated in the body, and that its tension was
dependent upon the state of health of the subject.
Some few years later I was invalided home, and at the
instance of Sir James Anderson and Sir John Fender to
whom the journal then belonged was associated in the
editorship of The Electrician, and also became editor of
The Electrical Engineer. In the latter paper, in May,
1885, I published an article entitled " The Human Body
as a Disturbing Element in Electrical Testing," from which
the following quotation may be made :
" I am of opinion that in every case where use is made
of an unshunted galvanometer of great sensibility the
operator should be careful to connect himself during the
test with an earth plate, instead of, as is usual, standing
upon some insulating substance. This conclusion was
forced upon me years ago. I was, in the ordinary course
of business, comparing a 10-microfarad condenser withone of
1 -micro capacity by Sir William Thomson's " (afterwards
INTRODUCTORY xxvii
Lord Kelvin) " method, employing a very sensitive Astatic
galvanometer and two platinum-silver resistances, arranged
so that a difference of one ohm resistance gave me a
difference of 001 microfarad capacity. The insulation
of the battery and other apparatus was absolutely
perfect ; I used a current due to very low electro-
motive force, in order to avoid heating, and took all the
precautions which are laid down by others and which our
own experience suggests. The 10-micro condenser varied
in the most inexplicable manner between 8-929 and 9-931
micros. In all there might have been a hundred readings
taken, each time, or almost each time, with a different
result, with a discrepancy of about 0-001 micro, and it was
not until I observed a slight galvanometric deflection while
the battery circuit was open that the probable cause
suggested itself to me. During the course of some experi-
ments I afterwards made under different conditions to
verify the idea then formed, I stood as closely as possible
to the galvanometer circuit, and upon being charged with
20 volts produced a slight inverse deflection upon the
galvanometer ; when the circuit was opened a slight direct
deflection was noticeable. After having connected myself
with an earth of low resistance the phenomenon ceased to
manifest itself and I succeeded in getting a balance. '
My association with Mr. Finlay, short as it was, was
fortunate. Had it not been for that association I should,
in all probability, have dismissed the vagaries of the
galvanometer as being due to leakage, and, so far as I am
concerned, the experiments might never have been made.
Hundreds of other electricians have observed the same
phenomena during the last thirty or more years, but have
not bothered themselves to do more than attend to the
xxviii INTRODUCTORY
insulation of their connections. Temperament may have
befriended me, but the germ of carefulness was implanted
by Mr. Finlay, and I am grateful to him for it.
The article from which I have quoted attracted the
notice of Dr. Stone of St. Thomas's, a correspondence
resulted, and, eventually, I collaborated, unofficially, with
him in the preparation of his Lumleian lecture of the year,
the subject being, " The Human Body Considered as an
Electrolyte."
At that time I am afraid we, neither of us, knew very
much about it, but although working in different sections
of the field of scientific investigation, we had both arrived
at one conclusion, viz., that local pyrexia interfered with
local insulation resistance.
The importance of this discovery can scarcely be over-
estimated, but we did not realise it ; he, not before his
death, which occurred not long after, I, not for many years,
because other occupations and duties intervened and
research work had to be relegated for the nonce to the
background.
It was some time about the year 1900 that I fitted up
a laboratory and seriously took up my task anew. And
then a curious thing happened. We had a juvenile party,
and some of the young people, inspired, perhaps, by a
magazine article or fairy-tale, asked me if apples were
electrical, if one could eat things which would make one
luminous, and so forth. I replied, " Come and see."
We went into the testing-room, and having procured some
apples and oranges and lemons, I connected two steel
darning-needles by two lengths of flexible wire to the
terminals of the galvanometer and, of course, obtained
deflections. These experiments were regarded by me, at
INTRODUCTORY xxix
the time, as " parlour tricks," and in making them I had
no object other than the amusement of the youngsters.
But when upon reversing an apple I obtained a reversal
of sign my interest was keenly aroused and a series of
experiments was initiated which are described in Part I,
and which, so far, touch little more than the fringe of the
subject.
From that time I went on working patiently between
intervals of strenuous commercial and professional life,
saying nothing, publishing nothing, but collecting data
upon which to found a considered opinion and this present
volume is the result.
A. E. B.
Part I
ELECTRICAL STRUCTURE AND
FUNCTION IN PLANT LIFE
STUDIES IN ELECTRO-PHYSIOLOGY
CHAPTER I
GENERAL
IT has long been known that the application of electricity
to the soil is sometimes beneficial to plant life, and some
remarkable results in the direction of increasing the
quantity and quality of crops have been in that way
obtained. But hitherto no adequate attempt seems to
have been made to ascertain if Nature has endowed the
vegetable world with any system by means of which
currents of electricity can be utilised, assimilated, or
stored.
The experiments, therefore, conducted during the past
thirty or more years have not been altogether conclusive,
and no really satisfactory evidence has yet been obtained
beyond the fact that, under certain conditions and in
certain circumstances, electricity is favourable to growth.
In Structural and Physiological Botany by Thome,
translated by Dr. Alfred W. Bennett, and accepted as the
recognised text-book in the technical schools of Germany,
there occurs the following passage :
44 The chemical processes within the cells of a plant,
the molecular movements connected with growth, and the
internal changes on which the activity of the protoplasm
depends whether exhibited in the formation of new cells
3 B2
4 ELECTRICAL STRUCTURE AND
or in motility are probably connected with the dis-
turbance of electrical equilibrium. The fluids of different
chemical properties in adjoining cells, their decomposition,
the evolution of oxygen from cells containing chlorophyll,
the formation of carbon dioxide in growing organs, and
the process of transpiration all these vital processes must
produce electrical currents ; although this fact has not yet
been experimentally determined or accurately investigated." *
Two of the greatest authorities upon Vegetable
Physiology are, or were, Sachs and Strasbtirger, although
equally valuable work has been done by Vines and Green.
Sachs, in his twelfth lecture, said : " That electro-
motive mechanisms are present in the normal life of the
plant itself may be in part directly demonstrated, in part
presumed on general grounds. It has been established,
for instance, that every movement of water in a tissue,
even in the woody mass, is connected with slight electric
disturbances ; and that these even appear when dis-
placements of water are caused by the mere passive
bending of a portion of a plant, or by movements of
irritability on its part. In addition we may assume that
the chemical processes in nutrition, continually going on
in the plant, and the molecular movements during growth
and the passage of fluids from place to place, are all
connected with electrical disturbances of various kinds,
although it has not been possible to demonstrate this
experimentally. We may also suppose that in the
ordinary life of land-plants especially, during the con-
tinually altering differences of electrical tension between
the atmosphere and the soil, equalisations take place
through the bodies of the plants themselves. The land-
plant rooted in the soil offers a large surface to the air by
means of its branches, and the roots are still more closely
in contact with the moist earth, while the whole plant is
* The italics are mine.
FUNCTION IN PLANT LIFE 5
filled with fluids which conduct electricity and are decom-
posed by currents. Such being the case, it can scarcely
be otherwise than that the electrical tensions between the
atmosphere and the earth become equalised through the
plant itself. Whether this acts favourably on the processes
of vegetation, however, has not been scientifically in-
vestigated, since what has been done here and there in the
way of experiments in this sense can scarcely lay claim to
serious notice."
Strasburger with whom must be associated Drs.
Schenck, Noll, and Karsten has nothing to say upon the
subject, and I think it may reasonably be assumed that
our knowledge of vegetable electro-physiology is summed
up in the extracts I have given.
The analogies, however, which exist in animal and
vegetable physiology, especially in the lower forms of
life, are sufficiently full of interest to stimulate further
research work. That locomotion and sensitiveness are
common to low plants as well as to low animals, that
marked similarity exists between the animal and the
vegetable cell, and that in the matters of the presence or
absence of cellulose and the nature of the food required by
both organisms there does not appear to be any absolute
point of distinction, seemed to me to invite investigation
and encouraged me to undertake it. The theory of
evolution, enunciated in its present form by Darwin and
by Wallace, regards all forms of life as having a common
descent, a true blood relationship, whence arises the
impossibility of drawing hard and fast lines of separation ;
and my own results are in perfect harmony with this
well-established conclusion.
We know, or at all events it can be demonstrated, that
man is a self-contained neuro-electrically controlled
machine, dependent for the due performance of his func-
tions upon a constant supply of nerve-energy at a low
6 ELECTRICAL STRUCTURE AND
potential ; that nerve-force is generated in the body with
each inspiration, and that the nerve-impulse is neuro-
electrical and not chemical. If that is so, and it cannot
successfully be disputed, it may reasonably be assumed
that in all probability electricity plays a part in the
vegetable as well as in the animal world. Investigation
has shown the soundness of this theory, as I hope to be
able to prove, and further research at the hands of men
more capable than myself may lead to far-reaching
consequences in the direction of an advancement of our
knowledge of practical horticulture and floriculture.
Briefly, the conclusions at which I have arrived are as
follows :
(1) Everything living, whether animal or vegetable,
has a well-defined electrical system ; the non-
living possessing capacity only ; and that only
in conjunction with moisture.
(2) Broadly speaking, the edible part of a fruit or
vegetable is the positive element, or that part
which yields a positive galvanometric reaction.
(3) Dry earth is a bad conductor of electricity, and
therefore water is required as an electrolyte as
well as being necessary in the formation of
protoplasm, etc.
(4) Every tree, shrub, plant, fruit, vegetable, tuber,
and seed is an electrical cell, differing from cells
made by human agency in that it cannot be
polarised or discharged so long as it remains
structurally perfect.
(5) The skin, peel, rind, or jacket of fruits and vege-
tables is of the nature of an insulating substance
primarily designed for the conservation of their
electrical energy.
(6) The electro-motive force of them all is the same ;
the current varying in accordance with Ohm's
v
law, i.e., C = , where R = the internal resistance.
FUNCTION IN PLANT LIFE 7
(7) Plants grown in pots or removed from the earth
and placed in other receptacles differ materially
in their electrical constitution from those grown
in the earth.
(8) If a suitable electrolyte, other than water, is
mixed with the soil it is possible to grow plants
with much less moisture, and
(9) Growth may be stimulated by means of a con-
tinuous current of electricity of low potential and
proper sign.
In the experiments of which an account is about to be
given the recording instrument was a Kelvin Astatic
Reflecting Galvanometer (see p. 235) of 80,000 ohms
resistance at 15 C., and a sensibility of about 4,000 divisions
of the scale, at a metre distance, per micro-ampere. My
chief difficulty was in the selection of a reliable form of
electrode. Those of the non-polarisable variety were, for
reasons into which I need not presently enter > deemed
unsuitable. Needles were obviously necessary. Platinum
was shown by Oliver Heaviside in 1885 * to set up secon-
dary action even in distilled water, and most amalgams
were open to the same objection as well as to the suspicion
of want of homogeneity. Finally, steel was chosen as the
metal, and the electrodes with which more than ten
thousand tests were taken without there being one dis-
cordant result were darning-needles of equal gauge con-
nected to flexible wires of low resistance. That there are
theoretical objections to this form of electrode I am well
aware, but, as I propose to prove, they cannot be upheld
in face of the evidence to be adduced.
In normal conditions of weather and in countries free
from frequent seismic and magnetic disturbances, the
Earth is always the negative and the Air the positive
terminal of Nature's electrical system.
* The Electrician.
8 ELECTRICAL STRUCTURE AND
Everything, therefore, that grows in the earth is charged
by the earth through the roots, and by the air through the
flowers and leaves (the lungs, as it were, of the tree or
plant), so that in the roots, stem, stalks, and veins the
tree, shrub, or plant has its negative terminals, while those
parts of the leaves between the veins are positive.
Examination of the vascular bundles and laticiferous
vessels of plants will make this clear.
In all fruits and vegetables the negative and positive
systems are plainly discernible once the eye has been
taught to look for and recognise them.
Before going into detail, however, it will be as well to
consider the electrodes.
I found that when two wires of equal gauge and length,
soldered to two steel needles of exactly the same gauge and
length, were connected to the terminals of the galvanometer
and the needles were inserted in various objects and
liquids, certain deflections were observed, and that such
deflections were not momentary but constant.
These deflections are explained as being due to galvanic
action.
There are two theories, i.e.
(1) Two metals that is to say, one needle being
electrically positive to the other in one exciting
liquid, or
. (2) One metal in two such liquids.
It will, however, be only necessary to consider the first
seriously.
Let us suppose that we are using two wires of exactly
equal length soldered to two steel needles as before men-
tioned, and that the object under examination is an apple.
In order to settle which is the positive and which the
negative side of the galvanometer scale from its central
zero, we will first connect the positive or carbon terminal of
a dry cell to the right-hand terminal, and the negative or
FUNCTION IN PLANT LIFE 9
zinc terminal of the cell to the left-hand terminal of the
recording instrument. The resultant deflection is to the
right of zero, and we may therefore call the right side of
the scale from zero positive and the left side from zero
negative.
Now, if we insert the needle connected to the right side
of the galvanometer in the stalk of the apple and the other
needle in the flower end, we get a constant negative deflec-
tion. If that deflection is due to galvanic or chemical
action, then so long as we do not alter the connections upon
the galvanometer, and reasoning upon the hypothesis that
the right needle is electrically negative to the left needle
and that chemical action is set up by their contact with the
malic acid of the apple, the deflection must continue to be
negative when the fruit is reversed and the right needle
is inserted in the flower end and the left needle in the stalk.
Also the signs of both deflections must be reversed if we
reverse the wires upon the terminals of the galvanometer.
But it is not so ; nothing of the kind ever occurs or can
occur. Every fruit will give a constant negative deflection
when the right-hand needle is inserted in the stalk, and a
constant positive deflection when it is inserted in the
flower end ; while every tree, shrub, plant, vegetable, and
individual leaf will yield a constant negative deflection
when the right-hand needle is connected with root, stalk,
or vein, and vice versa. The wires may be reversed upon
the terminals of the galvanometer as often as desired.
There will be no difference whatever in the phenomena
observed. In the case of pot-grown plants and fruits,
etc., polarity is reversed because the moist soil in the pot
receives its charge from the positive air instead of from
the negative earth.
If, however, diffusion takes place by reason of injury or
decay, and the plant, vegetable, fruit, or leaf becomes
rotten, no reversal of sign will be obtained.
10 ELECTRICAL STRUCTURE AND
THE APPLE.
Fig. 1 illustrates the electrical structure of the apple.
The stalk, receiving its negative charge from the earth,
communicates directly with the negative core, which, as
will be seen, is insulated from the positive or edible portion.
The core terminates at its upper end, it will be observed,
in a dry plug the remains of the flower while the stalk
is always sealed, either by dry fibre or by a gummy or
resinous secretion. The rind or outer covering is of
enormous resistance, and is evidently designed to conserve
the energy of the cell by giving it high absolute insulation.
From Fig. 2 we gather some idea of the means adopted
by Nature to prolong life.
In the example shown, seven days had elapsed since
the division was made, the surfaces had partially dried,
probably to increase their resistance and lessen liability
to evaporation, the walls of the core had similarly har-
dened, and the rind or peel had closed round the edges to,
we may assume, prevent the loss of any of the juice
necessary to the apple's continued electrical activity.
The pear and the quince so nearly resemble the apple
that it is unnecessary to describe them. The only difference
is that the core is more elongated in shape and is placed
at a slightly greater distance from the stalk than in the
case of the apple.
THE BANANA.
It will be seen that the negative terminal the stalk
is connected with the skin and an inner lining from which
the positive flesh of the fruit is instantly detachable. No-
where does there appear to be any actual electrical contact
between the negative and positive systems except, pos-
sibly, by osmosis the flesh being enclosed in an envelope
and as the whole of the flesh is positive the dietetic value
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FUNCTION IN PLANT LIFE 11
of this fruit should be high. Unfortunately it has when
ripe, and probably owing to its porous skin, a compara-
tively low insulation resistance and therefore a short life.
Figs. 3 and 4 will serve to illustrate the points mentioned.
THE TOMATO.
The tomato (Fig. 5) affords us convincing testimony of
the reliability of our electrodes, because during the late
summer we can take one grown in the open ground and
one from the greenhouse and test them under exactly the
same conditions and at the same time. That grown in the
open ground will be found to be negative at the stalk and
positive where the flower originally appeared, while that
from the greenhouse, where it had been deprived of its
supply of current from the negative earth and compelled
to take its root-charge from the positive air, assumes an
opposite polarity and is positive at the stalk end, etc.
These remarks apply to all fruits and vegetables cultivated
alike in the garden and in pots in the greenhouse, such as
the cucumber, the orange, lemon, etc., etc.
But if the soil in the pot is connected by a metallic
conductor with the earth (see illustration), no change of
polarity will occur.
12 ELECTRICAL STRUCTURE AND
THE ORANGE, LEMON, GRAPE-FRUIT, ETC.
In testing these fruits great care has to be exercised
owing to the large quantity of juice they contain, the
rapidity of its action upon steel, the danger of diffusion,
and the extreme delicacy of cells of which the fruits are
mainly composed and the narrow contacts they offer.
Their structure, electrically considered, is best explained
by Figs. 6, 7, and 8, but especial notice should be taken of
the wonderful manner (shown in the sectional plans) in
which the positive flesh of the fruit is surrounded by
protective material, and how that protective material is
connected in turn with the central and outer negative
system. Nor is their absolute insulation provided for in
a less remarkable manner. The skins of the orange and
lemon in particular appear to be porous, but in reality
they are built up of innumerable cells containing a highly -
resistant ethereal oil which, until expelled by evaporation,
conserves their energy.
THE TURNIP
(Swede and Mangel -Wurzel, etc.)
In Fig. 9 it will be seen that the negative system of this
vegetable extends from the root along the outer perimeter
and to the whole of the thickness of the rind. The inner
lining of this an envelope, as it were is probably pro-
tective material, and, so far as I am able to judge, the
whole of the interior is positive ; that system extending to
the positive terminal, or flower end ; and to those portions
of the foliage free from stalks and veins which connect
directly with the negative system.
From an electrical point of view the turnip compares
unfavourably with many other vegetables. At no time
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fiPllli
>S G^
FUNCTION IN PLANT LIFE 13
is its skin or rind of very high resistance, and when a
turnip is divided as in the illustration given it soon,
especially if kept in a dry place, becomes unfit for food.
Unlike some other vegetables, such as the potato, it does
not appear to be provided with the means of forming fresh
insulating material upon the cut surface, with the result
that it dries up, and, not being able for that reason to
absorb charge from the air, loses its electrical activity and
degenerates into a spongy, fibrous, and inedible mass. If,
however, it is kept in a moist condition it retains capacity,
or power of absorption of electricity from the air, and can
be preserved for a longer period of time. This was ascer-
tained by cutting turnips in halves. Figs. 10 and 11 show
the halves of two turnips taken from the same bunch. That
given in elevation was kept under water for ten minutes
three times daily, while the other (sectional plan) was left
untouched ; both being subjected to identical atmospheric
conditions. In the same figures we have the two halves
of the turnip in elevation. These were treated as above,
and in both instances were sketched after an interval
of eight days. They call for no further comment from
me.
THE CARROT AND PARSNIP.
Fig. 12 sufficiently illustrates the electrical structure of
these vegetables, but attention may be drawn to the fact
that the roots are connected directly with the negative,
and that the central positive system is insulated or pro-
tected from the former in the manner shown. If these
vegetables are divided in the middle, lengthwise, the
negative can be separated from the positive portion with
the fingers, leaving the latter exposed as a tongue and
exhibiting the former encircled by root-filaments.
14 ELECTRICAL STRUCTURE AND
THE ONION.
This is an unusually difficult vegetable to test, in that
while the bulb appears to form a complex cell, the inter-
mediate contact-spaces are so narrow and the liability to
diffusion so great, when the onion is divided, that I am
unable to speak with certainty. Botanists, however, will
readily solve the problem, which, from an electrical stand-
point, is to differentiate the layers connected with the root
from those in alignment with the tubular leaves. The
former will be negative and the latter positive.
Fig. 18 depicts the structure of the onion as it is pre-
sented to the unaided eye and in so far as I am able to
determine it galvanometrically. The negative system
seems to extend from the root to the outer second and
third layers of the bulb, between which and the central
positive system there exists a membranous and probably
protective lining. The contacts afforded by the poles are
well defined, the absolute insulation is extraordinarily high,
and altogether the onion is a vegetable cell of a very
perfect description. Its electro-motive force is, ap-
proximately, 0-086 volt ; the current varying, of course,
with size. Such a cell is invaluable in the testing-room
for such work as, for instance, taking the constant of a
sensitive galvanometer or comparing deflections from
living muscle or tissue, instead of using for the purpose a
standard cell liable to polarisation when employed without
very high resistance in circuit.
TUBERS.
These differ in their electrical constitution from root-
vegetables proper and from fruits, in that they are not
merely bipolar, but have a number of positive and negative
terminals. I have taken two examples, i.e., the potato
and the Jerusalem artichoke, reserving others for future
^vestigation.
FUNCTION IN PLANT LIFE 15
THE POTATO.
The potato plant receives its supply of current direct
from the earth, but it is open to doubt whether such is the
case with the tubers to which it gives birth. They are
connected with the parent plant by a filament or filaments
not altogether unlike the umbilical cord of the human
through which or by means of which they are energised.
In the potato shown in Fig. 14 I can trace only two eyes
to which such filaments might have been attached (marked
a and b). They are negative terminals communicating
with the outer negative system, while c, d, and e are
terminals (positive) of the lines /, g, and h. It is only
when these slightly darker lines reach the jacket that we
find a live or prolific eye. The unprolific eyes, so called,
are those by which the tuber is attached by a filament or
filaments to the parent root.
It has been seen that some fruits seek to protect
themselves when cut or injured, or rather that Nature has
made in that regard some provision for them.
In this respect the potato is well endowed. Very
shortly after being cut it exudes a starchy substance which
dries rapidly, and forming a film over the cut surface,
restores in some measure, if not entirely, the impaired
insulation, as well as preventing loss, by evaporation, of the
fluid, without which it must become electrically dead.
This tuber will, in fact, keep longer and grow better after
being injured than any other member of the vegetable
world with which I am acquainted, other things being
equal.
THE JERUSALEM ARTICHOKE.
There are several points of difference between this tuber
(Figs. 16 and 17) and the potato. It is covered with root-
filaments, is distinctly bipolar as regards the ends, and does
16 ELECTRICAL STRUCTURE AND
not appear to be provided with so efficient a repair outfit.
In common with the potato, it has a marginal negative
system and several positive terminals, but I should imagine,
from the number of root-filaments, that instead of being
dependent upon the mother -plant it derives its electrical
supply directly from the earth.
LEAVES.
I selected a few examples from evergreen and deciduous
leaves with a view to seeing what difference, if any,
existed between them as regards relative conductivity, the
ramifications of their negative systems, and the quality of
the main conductors the stalks through which current
is conveyed to them from the earth.
As a rule, in deciduous leaves the veins do not seem to
me to form so complete and extensive a network as in
those of the evergreen variety. They are, moreover, not
so well insulated, are thinner in texture, and, if they lose
their moisture under the influence of prolonged summer
heat, become electrically inert and fall. Such a leaf is
that of the horse-chestnut (Fig. 18), and it offers a sharp
contrast to that of the ivy (Fig. 19), in which the negative
veins form an almost complete network, and which carries
three principal veins as against the single one of the horse-
chestnut. The leaf is also more substantial, is infinitely
better adapted to retain its moisture, and therefore its
conductivity and capacity of electrical absorption, while
the walls of the veins appear to possess high resistance,
or, in other words, a high degree of insulation ; the inter-
mediate or positive parts of the leaf being able in the
presence of occasional rain or even a damp atmosphere to
receive positive charge from the air.
This perfection of insulation and inherent interior
moisture extend to the stems of the plant, so that, their
feri
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iO
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CO
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u
Ji
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&*XJ
FUNCTION IN PLANT LIFE 17
internal resistance being unusually low, a current in excess
of the average is carried by them, and may possibly ex-
plain, in some measure, the ivy's tenacious hold upon life.
The insulation is probably due to the numerous resin-
passages found in the plant.
Do VEGETABLES AND FRUITS POSSESS CAPACITY ?
The answer to this question, so far as the experiments
have gone, is in the affirmative. No attempt has been
made to determine, by comparison with a standard con-
denser, the electrostatic capacity of any vegetable or fruit,
as the conditions would vary enormously with size, degree
of moisture present, and insulation resistance, without
offering adequate compensation for the labour involved.
It was therefore thought sufficient to ascertain if fruits
and vegetables when put in circuit with a battery and a
recording instrument, merely, by reason of their conducting
juices, formed part of a simple circuit, or whether after the
battery had been disconnected they retained charge :
whether by reversing the polarity of the battery the
polarity of the object under examination could be altered,
and for how long any such charge or change, if any, was
observable.
The first experiment was with a quince. With the
right-hand needle inserted in the stalk and the left needle
in the flower end it gave a constant negative deflection.
The needles were allowed to remain in the fruit, but the
wires to which they were attached were connected to a dry
cell for five minutes, i.e., right needle to carbon and left
needle to zinc. The resultant deflection was strongly
positive, discharge took place slowly, and it was a consider-
able time unfortunately not recorded before the original
negative deflection was restored.
At a later date I tested a number of fruits and
c
18
ELECTRICAL STRUCTURE AND
vegetables, using a reflecting galvanometer of the
D 'Arson val type.
In every case the connections were as shown by Fig. 21 A,
the needles, except where otherwise mentioned, being left
in the object under examination during the whole of the
test. The scale limit was 250 mm. from a central zero.
In every case, also, the fruit or vegetable gave, with the
Fig. 2lA. CONNECTIONS IN CAPACITY TESTS.
x = vegetable cell.
= positive terminal of same.
b -negative
c =dry cell 1*5 volts.
d = plug switch.
G = galvanometer.
right needle inserted in the stalk end, a constant off-scale
negative deflection.
It is not proposed to give full details, as they might
become wearisome, but to summarise the results obtained
in each test or series of tests.
THE ONION.
With the right needle to the root and the left needle
to the foliage end it gave a constant, fairly rapid, off-scale
negative deflection. Five minutes 7 charge from a cell of
15 volts positive to root and negative to foliage merely
FUNCTION IN PLANT LIFE 19
reduced this deflection, and it was necessary to give a
further five minutes' charge. At the end of this time it
went rapidly off-scale positive and remained off-scale for
fifteen minutes. The connections were then earthed for
five minutes through 5,000 ohms, when the charge was
found to be dissipated and the true polarity restored.
In a second experiment with the same onion a further
ten minutes' charge was not fully discharged until forty
minutes after the first reading.
A STICK OF ^RHUBARB.
This was charged for five minutes and the cell dis-
connected. The deflection was then off-scale positive.
Five minutes later it had fallen to 160 mm. positive, and
at the end of the tenth minute risen to 180 mm. As this
might have been due to the effect of the juice upon the
electrodes, these were removed, cleaned, and carefully
reinserted, when D = 180 mm. positive, rising in a further
five minutes to 250 mm. Five minutes E, however,
removed the charge and the original polarity returned.
THE APPLE.
This fruit was large, ripe, and in peifect condition, and
exhibited an unusual quantity of current. Ten minutes'
charge with 1-5 volts merely reduced the deflection to
50 mm. negative. I therefore gave it another five
minutes, when D = rapidly off-scale positive. Ten
minutes later it being still off-scale the connections
were put to E for five minutes and the electrodes removed
and cleaned. D was then 250 mm. positive and five
minutes later 235 mm. positive. It had then, unfortu-
nately, to be left insulated until the next day, when it
had fully recovered.
SO ELECTRICAL STRUCTURE AND
THE BANANA.
This was really a small plantain, about 7 in. long.
After ten minutes' charge D == rapidly off-scale positive ;
five minutes later it was 190 mm. positive, and in twelve
minutes thirty-five seconds more had gone off-scale
negative, that is to say, had fallen 440 mm. It
did not, however, quite regain its original polarity until
it had been short- circuited through 5,000 ohms for a further
twenty minutes. Even so it discharged itself in twenty-
eight minutes as against forty-one minutes of the onion,
and this I attribute to its comparatively low absolute
insulation resistance.
THE TURNIP.
I took two 'examples of this vegetable. The first was
oval in shape, weighed 3 oz.. and had been kept in a dry
room for a week, both poles being dry and fibrous. The
second was an almost perfect sphere, 10J in. in circum-
ference, weighed 10 oz., and had been recently pulled.
The root was not dry, the foliage end white and exuding
moisture. No. 1 was charged for ten minutes as before,
when D = very rapid off-scale positive. Short-circuited
through 5,000 ohms it remained off-scale for thirty-two
minutes, and did not regain its former polarity for thirty-
three minutes more, showing a slow discharge, but one,
after allowing for higher insulation, not inharmonious with
the preceding data. Upon examination the right needle
was found to be blackened by electrolysis ; the left needle
having traces only.
No. 2. Ten minutes' charge, as before. Immediate
D = very rapidly o'ff-scale positive. In three minutes the
light returned to 250 mm. positive, and in six minutes
more had gone off-scale negative ; the vegetable recovering
FUNCTION IN PLANT LIFE 21
polarity almost instantly. The right needle was quite
blackened and the left needle clean. As this discordant
result might have been due to leakage through the moist
poles or terminals of the vegetable, I painted both with
a non-conducting solution and allowed it to dry, in order
to see if higher insulation would slow down the rate of
discharge.
The experiment with No. 2 was then repeated under the
same conditions but with fresh points of contact.
After ten minutes' charge D = very rapid off-scale
positive. The vegetable then remained short-circuited
through 5,000 ohms. D continued off-scale for seventeen
minutes, when the vegetable was accidentally knocked over.
No. 2 (third experiment). The connections were put
to earth until the vegetable regained polarity and gave
perfect reversals. It was then charged for ten minutes
with 1-5 volts, when D = very rapid off-scale positive, not
falling to 250 mm. positive until sixteen minutes later.
The period of fall from 250 mm. positive to 250 mm.
negative was eight minutes, and ten minutes later the
vegetable had recovered. The conclusion, or one con-
clusion, to be drawn is, of course, that absolute insulation
is a factor of primary importance in retention of charge.
THE ORANGE.
Circumference 8 J in., weight 5| oz. After ten minutes'
charge D = fairly rapid off-scale positive. In ten minutes
it fell to 250 mm. positive, and in fifteen minutes more the
light had reached 250 mm. negative ; the fruit regaining
its former full polarity fifteen minutes later. The right
electrode showed a mere trace of electrolysis. The charge
in this case remained on the positive side of the scale for
nineteen minutes, but the absolute insulation of the orange
and lemon is not very high.
22 ELECTRICAL STRUCTURE AND
'CHAPTER II
SOME SEEDS IN THEIR ELECTRICAL ASPECT
So far I have not been able to find time to study the
electrical problems presented by germination, but I am
convinced that when this is done even greater proofs of
the universality of the law will be forthcoming. The
subject is a sufficiently vast one to call for more than the
labours of one man and the compilation of one book, but,
so far as I am concerned, it must be reserved for future
investigation.
The examination of seeds in their various stages of
development present features of interest which cannot fail
to claim the attention of the student, and although my
opportunities for observation have been limited by a
variety of circumstances, I am glad to be able to offer some
food for thought and, I hope, additional stimulus to
research.
During our consideration of the nature of the nervous
impulse we, or at all events some of us, learn that in the
case of the human foetus independent existence is only
begun when air (oxygen) is first taken into the lungs and
complete circulation established until that moment the
child is dependent upon the maternal blood-stream and
will note, in the chapter upon Cell-reproduction, that the
so-called " resting " stage of a cell is really a developing
stage. That being so, it follows, I think, logically, that
while a seed is still attached to the parent plant or tree it
is equally dependent with the unborn child, and that the
FUNCTION IN PLANT LIFE 28
same law which governs cell -division should guard the
immature seed from the possibility of premature germina-
tion by withholding from it a perfected electrical system.
Unless that is so there is a flaw in our reasoning, or our
understanding of the law is at fault.
THE HORSE-CHESTNUT.
At the time of year of the experiments about to be
described (September) and for the following few weeks
the seeds were in various stages of development, and could
be studied at leisure. The method adopted was to
cut the pods in halves longitudinally and test them gal-
vanometrically, to ascertain the relative sign and electrical
activity of their various parts. The following photo-
graphs are illustrative of the result :
Outer Lnsu[at<nfme m 6rane
Fig. 22. SECTION OF HORSE-CHESTNUT. [Original photo.]
a, a, part, consisting of white, pithy substance, which is positively
charged ; b, insulating membrane immediately enveloping the seed
substance ; c, conducting layer, negatively charged ; d, insulating mem-
brane enveloping the conducting layer ; e, seed substance yielding only a
few millimetres positive deflection as against the 1,000 mm. negative of
the conducting layer ; /, outer insulation, porous, and of low resistance.
The next photograph shows the negative terminal and
system more clearly, and gives a better idea of the extent
of the positively charged material. This seed is not in
24 ELECTRICAL STRUCTURE AND
such an advanced stage of development as the preceding
one, and the pod contained two seeds.
Fig. 23. SECTION OF HORSE-CHESTNUT. [Original photo.]
Two insulating membranes are shown, but there is a
third, not adherent to the seed, but lining the cavity in
which it lies, and designed, there can be little doubt, to
prevent a positive charge from reaching the immature
seed ; inasmuch as this membrane appears to be formed
before the membrane d attains the required resistance.
The function of the other two membranes, b and d, en-
closing the actively charged conducting layer, c, calls for
more elaborate if hypothetical explanation.
Apart from the seed itself the major portion of the pod
is taken up by a white, pithy substance of positive sign ;
probably charged by the air through the epidermal spines
or pores. While the seed is growing it does not, I imagine,
require direct, but rather modified, electrical stimulus.
From the seed substance itself I obtained deflections of a
few millimetres only, whereas the conducting layer, c, gave
excursions of one thousand and over. Assuming, then,
that for some wise purpose possibly to give adequate
time for development stimulus to the seed substance is
modified, the function of the conducting layer, c, becomes
apparent, inasmuch as it would play much the same part
FUNCTION IN PLANT LIFE 25
as the lymph space on a nerve-fibre or the copper taping on
an insulated wire in preventing an induced charge from
passing it.
Now the part a, a is positively charged by the air and
has greater surface area than the conducting layer c.
We should therefore find as we do find that the tension
of c is in excess of that of a, a, and that the sign is negative
instead of positive.
That is while the seed is still attached to the tree and
has no separate and independent existence.
But in course of time the pod falls and releases the seed
by splitting segmentally. The latter we must suppose to
be planted or buried in the soil and to be thereafter depen-
dent upon the earth, as man is mainly dependent upon the
air as the source of electrical energy. Obviously, then,
some change must take place to enable the seed to survive,
and that change is a very important one. The conducting
layer, c, dries up, and therefore ceases to intercept charge,
but the outer membrane, d, after contact with the damp
soil, would become a conductor, and without the inner
membrane, b, no electrical system could obtain. But with
d as a conductor and b as the insulating material, induction
could take place, and the seed substance receive a positive
induced charge in the following manner
charge
Jffembrane d.. conductor
6, : non-conductor
conductor
Fig. 24.
so that the two membranes are necessary both while the
seed is in the pod and after it has been released.
Fig. 25 shows the final appearance of the membranes
ELECTRICAL STRUCTURE AND
d and b. It is, however, not improbable that instead of the
whole of d becoming conductive, only the part g illustrated
by Fig. 25 may so function. This is suggested by the
greater desiccated space between the membranes at that
point. But even in that event the only material differ-
ence, so far as I can see, would be that the tension of
e would be lower than that of d by reason of the larger
surface area ofV
Prior to the completion of the insulating system the
conducting layer c seems to receive
charge directly through the stalk of
the pod. During such time, there-
fore, the part g, or the depression
marked h thereon (Fig. 26), would
probably be the point of contact.
As regards the unusually elabo-
rate insulation of the pod and
seed of the horse-chestnut, it is
worthy of remark that the secretion
both of the white, pithy material
and the seed substance is markedly acid, staining steel and
instantly turning litmus-paper red. Neither of the three
Fig. 25. SECTION OF
HORSE-CHESTNUT SEED.
Showing the final ap-
pearance of the mem-
branes d and b.
[Original photo.]
membrane d
Fig. 26. HORSE-CHESTNUT SEED. [Original photo.]
The part g occupies about one-third of the area of the membrane d f
h is a small circular depression upon g and is probably of the nature of
a contact before the insulation is completed.
membranes, however, has any effect upon litmus-paper,
and, so far as I could determine, all are, as one would expect,
chemically neutral.
FUNCTION IN PLANT LIFE
27
Fig. 27 gives another view of the dried-up layer, c,
and shows a tongue-like projection of the seed substance
atft__
Fig. 27. SECTIONS OF HORSE-CHESTNUT SEED.
[Original photo.]
Showing projection of seed substance.
This tongue-like projection, k, does not connect with h, nor is it so
pointed as in the edible chestnut ; more frequently it resembles the end
of a dumb-bell when cut in section transversely. The part g is assumed,
in this instance, to be the bottom of the seed.
similar to that of the edible chestnut and insulated by the
inner membrane b in the same manner. The probable
purpose of this is suggested later on.
A CONTRAST.
I had before me, uncut, an edible and a horse-chestnut,
both in pod. They were free from spines, were of the
same colour, size, and shape, and there was nothing in
their outward appearance to differentiate them, except
that upon one the stalk still remained, to remind me that
it was the horse-chestnut. I cut the latter in halves, as
before, and photographed it. As it was in all its details
exactly similar to Fig. 22 there is no need to reproduce it.
I then proceeded to treat the
EDIBLE CHESTNUT
in the same way, and photographed the two separate
halves, shown in Figs. 28 and 29. The difference is very
28 ELECTRICAL STRUCTURE AND
remarkable. At all stages of development of the horse-
chestnut the seed substance is solid, and fills the whole of
the space within the inner membrane b, as shown in
Fig. 22, but in the edible chestnut it is more suggestive
of a foetus in the womb. I have cut some pods (un-
fortunately not now available for reproduction) in which
the seed substance appeared in semicircular shape, and
offered a weird resemblance to the foetus at a very early
period of its growth. Apart from that, however, there are
other essential points of difference. Both in the horse-
chestnut and the edible variety the secretion is markedly
acid, but whereas in the first the seed substance holds very
little liquid, that of the second is so heavily charged with
it as to fill or almost fill the cavity i, when the pod, and
with it the seed, is divided.
In the case of the horse-chestnut the cut surface of the
seed soon discolours and becomes a brownish-yellow ; that
of the edible chestnut remains white for a much longer
time, although the conducting layer c dries up almost
immediately. One is a seed, pure and simple ; the other
is both a seed and a food.
As will be seen in Figs. 22 and 28, the construction
electrically is much the same in both seeds, but whereas
in the horse-chestnut the seed substance is closely adherent
to the inner membrane b throughout, only a small portion
of the seed substance of the edible chestnut, in the posterior
part of j, is in its adolescence adherent to it, and this
part, as in the horse-chestnut, penetrates or protrudes
through the inner membrane by means of a tongue-like
projection to the limit of the conducting layer, c, which is
thicker than in the horse-chestnut seed. It, however, does
not connect with g (Fig. 25), but is nearer the centre of the
seed (g being, in the photograph, rather high up on the
left). This tongue is enveloped by an insulating membrane,
by which it is separated from the layer c and the outer
FUNCTION IN PLANT LIFE 29
membrane d, and may be designed to facilitate induction
between the conducting layer and the seed substance,
inasmuch as the latter, unlike the horse-chestnut, is not
adherent to the inner insulating membrane 6, except at
this point. Two considerations at least present them-
selves. Capacity in the case of vegetables and fruits is
governed by the nature and quantity of the conducting
liquid as well as by the specific inductive capacity of the
dielectric, and the area of the respective plates or discs or
membranes and their distance from each other ; and upon
capacity plus absolute insulation the life of the vegetable
or fruit depends. In the horse-chestnut assuming specific
inductive capacity and absolute insulation to be the same
in both we have the plates of comparatively large area
and close together, but with very little moisture. In the
edible chestnut one of the conducting surfaces, i.e., the
seed substance, is irregularly shaped, is removed in youth
except at the posterior part of j from the membrane b,
but contains a large quantity of moisture ; is, in fact,
surcharged. Actual test showed the tension of the seed
substance to be higher than that of the horse-chestnut, and
this would be in accordance with established laws.* But
what is the purpose underlying it ?
I may be wrong, but a possible explanation presents
itself.
Let us suppose that the horse-chestnut seed, not being
intended for food, is destined only to ripen, to fall from the
tree and pod, and to be buried in the earth to reproduce its
species. That would seem to be the sole object of its
creation, and nothing but the perfection of its insulation
would equip it with a sufficiently robust constitution to
enable.it to survive prolonged exposure under conditions
unfavourable to germination.
* See chapter on INDUCTIVE CAPACITY.
SO ELECTRICAL STRUCTURE AND
The edible seed, on the other hand, must, if it is to be
useful as a food, have keeping qualities, be able to preserve
Srefative. terminal
U u,ter insulation
Fig. 28. SECTION OF EDIBLE CHESTNUT. [Original photo.]
a, a, a, a, a*= positively chargedfwhite, pithy substance ;" b, inner
insulating membrane ; c = conducting layer ; d = outer insul iting
membrane ; e = seed substance ; j = beneath this is the tongue-like
projection ; i = cavity in which the seed substance is ensconced.
itself unimpaired for a considerable period of time, and in
this we may find a reason for the quantity of moisture with
which it is, under considerable pressure, charged. But
Fig. 29. SECTION OF EDIBLE CHESTNUT : THE OTHER HALF.
[Original photo.]
The seed substance seen in the central cavity is not attached in any
way to it. Before division of the pod it formed, of course, part of the
seed substance shown in Fig. 28.
it is also a seed, and when it is planted in the soil and the
outer membrane or some portion of it becomes a
FUNCTION IN PLANT LIFE 31
conductor, we have, although in a slightly different form,
the same electrical arrangement as shown in Fig. 22 ;
the membranous covering of the tongue of the seed sub-
stance providing the dielectric and the seed substance
itself the inner or second conducting surface.
It is worthy of note that in the edible chestnut the
white, pithy, positively charged area is larger other
things being equal than in the horse-chestnut, and this
might account for the conducting layer, c, of the first
taking, as is the case, a higher negative charge than
obtains in the second. It may also explain the slightly
increased positive electrification of the seed substance of
the former.
As regards what I have termed a " repair outfit," both
the horse and the edible chestnut exude upon their cut
surfaces what bears the appearance of a starchy secretion.
This dries, and not only checks further evaporation of
moisture from the seed substance, but to some extent
restores the lost insulation. In the potato the phenomenon
is particularly noticeable, and the film is very quickly
formed. With the chestnuts the process is slower, but is
a protective measure of the same order. It would be
interesting to see whether in this case division of the seed
prevents germination.
Another matter to which I should like to call attention
is that when freshly cut, the seed substance of the ripe
horse-chestnut is cream-coloured, or rather white, with a
faint tinge of lemon-yellow. After exposure to light, and
as soon as the starchy film develops, the cut surfaces
become yellowish-brown, with a deeper tint of yellow
showing beneath. This is, no doubt, a matter of electro-
chemistry, and as such somewhat beyond my purview, but
the suggestion has occurred to me that it may be a measure
of protection against actinic rays, or changes conceivably
introduced by them.
32 ELECTRICAL STRUCTURE AND
THE ACORN.
A beautiful simplicity characterises this seed, and one
might well believe that from it was borrowed the principle
of the modern incandescent electric lamp-holder.
As will be seen from the example given in Fig. 30, the
cups in which the acorns are seated are joined up, as it
were, in series, while the negative terminal is in the form
of a circle, a, at the bottom of the cup ; the seed carrying
upon its posterior part a circular protuberance, b, which
seats exactly upon the contact a.
Fig. 30. ACORNS. [Original photo.]
Electrically considered, the acorn is similar in con-
struction to the horse-chestnut seed. There are three
insulating membranes, and the secretion of the seed sub-
stance is also distinctly acid. It should have a fairly long
life owing to the excellence of its absolute insulation, to the
ample provision of moisture, and to the fact that it can
take in positive charge from the air through the point at the
apex of the seed.
In common with other seeds, such as the Barcelona
nut, etc., there are sometimes two seeds within the shell.
FUNCTION IN PLANT LIFE 33
When that happens and the acorn is cut in halves longi-
tudinally it presents the following appearance:
Fig. 31. DOUBLE ACORN IN SECTION.
The sides and lower surfaces of 1, 2, 3, 4 the cut
surfaces only being exposed are sheathed in insulating
membranes, which extend to and cover them from the inner
part of the contact a after the acorn has ripened.
COB -N UTS.
After discovering that Nature had, for a reason not
yet understood, joined up acorns in series, one remembered
that other things with which we are familiar are connected
either in multiple arc or clusters in series. The cherry,
with three or more stalks tapped off a main contact, is an
excellent example of this, and I wish I had sketched or
photographed a group of them when they were in season.
Fortunately, however, we had not to look far for other
specimens of the Great Electrician's craft. It was the
time of year for cob-nuts, and the cluster shown in Fig. 32
served to illustrate one method of connecting which appears
to be in the above category. The main lead, the stalk,
it will be noticed, is unusually thick. It carries current to
supply four nuts, and if we imagine them to be incandescent
lamps instead of nuts we know we should have to make
similar arrangements for their supply.
Where it joins the base of the cluster, as photographed,
the stalk splits into four branch leads, each of which
connects with a cup not unlike that of the acorn, but out-
wardly continuous with the foliage, into which the nut fits
D
84 ELECTRICAL STRUCTURE AND
to make contact at its base. This, however, is not small
as in the acorn, but extends to the whole of its posterior
part. The cup, however, as shown in Fig. 88, is not
Jregative teadfrvm earth.
Fig. 32. CLUSTER"OF;OB-NUTS. [Original photo.]
continuous with the foliage, but is insulated from it by a
fibroid layer which separates it electrically from the
negative terminal or lead.
i ve cup
fibroid insulating layer
fa u>kick leaves are attarf . --
Fig. 33. FOLIAGE AND CUP OF COB-NUT OPENED OUT.
[Original photo.]
A longitudinal section of the ripe nut reveals much of
interest. The secretion is only slightly acid, and insulation
is regained in this instance by the rapid exudation of a
wax-like secretion upon the cut surfaces. In the specimen
FUNCTION IN PLANT LIFE 35
examined there was clear evidence of the previous existence
of the conducting layer, c, and the three membranes were
present, i.e., the outer shell, a fibroid lining within that,
and a third enclosing what I have termed the seed sub-
stance. In lieu of the tongue-like protuberance with
which the chestnuts are provided a sharp point projecting
inwardly from the base of the nut seemed to have served
the same purpose, and at the apex was another point
evidently open at one time to the air. In regard to
colouring there was again in the white of the nut a faint
tinge of lemon-yellow. I exposed one half to bright and
the other to diffused light for four hours, when that in
diffused light was apparently unchanged, while the other
had taken on a tint of slightly deeper yellow.
THE ELECTRODES AND ELECTROLYSIS.
Where contacts of prolonged duration are made, as
in the foregoing tests for capacity, suspicion naturally
attaches to the electrodes, and it might be thought
that the changes of polarity observed were due to
polarisation. In this connection I would point out two
things, i.e. (I) the needles were in some instances
cleaned and reinserted without polarity being affected,
and that in the orange test there were merely signs
of electrolysis, and (2) that supposing 1-5 volts had in
ten minutes polarised the electrodes inserted in the
fruit or vegetable to such an extent that polarity was
reversed for twenty minutes, it is difficult to see how an
electromotive force of about 0-086 volt (i.e., that of the
vegetable cell) could restore the original polarity in another
twenty minutes while the electrodes remained in position.
Moreover, I have by repeated experiments, extending over
a course of years, established the fact that it is impossible
to alter the polarity of a vegetable cell by subjecting the
86 ELECTRICAL STRUCTURE AND
needles to electrolytic action possibly set up when they are
left in such cells for several days at a time. Another thing
of which sight should not be lost is the initial test of
Turnip No. 2. The first charge of ten minutes with 1-5
volts was dissipated in less than ten minutes, but when the
absolute insulation of the vegetable was improved in the
manner described in the second and third tests it did not
recover until thirty-four minutes had elapsed. The
electrolytic action and consequent polarisation should have
been the same in both tests, and altogether I think it must
be agreed that the weight of evidence is in favour of
capacity, and not polarisation of electrodes, as explaining
the phenomena, although there can be no doubt that the
electrodes were affected to some extent by electrolysis.
PRIMARY OR SECONDARY CELLS ?
The problem is, no doubt, possible of solution, but in so
far as 1 am acquainted with the chemistry of the subject,
I have yet to hear of a cell made by man in which there
occurs no disintegration or no change, and which cannot
be either polarised or discharged by continued short-
circuiting.
Some vegetables and fruits, it is true, are more liable
to decay than others, but decay interferes with their
electrical activity only by diffusion, by breaking down the
protection between the negative and positive elements,
and, possibly, by setting up local action. Once that
happens the process of decay is very rapid.
Their life that is to say, their edibility as well as
electrical activity appears to depend largely if not to be
in direct ratio to their absolute insulation resistance. Of
all vegetables the onion has the highest and best absolute
insulation, while among fruits the apple, the pear, and the
quince, etc., are in the premier class. I have short-
circuited onions through 0-1 ohm for many days at a time
FUNCTION IN PLANT LIFE 37
without finding in them any evidence of polarisation or
discharge, and as the E.M.F. of them all is the same
the current only varying in accordance with Ohm's law
the onion is, in my opinion, an ideal standard cell of low
electromotive force for delicate galvanometric work. The
apple and pear, offering as they do smaller contacts and
more liability to diffusion at the points of contact, are
not so generally useful, although, with care, they are
reliable.
In regard to plants, shrubs, and trees, however, I have
observed that during such time as they are " resting," as
in the late autumn, winter, and early spring months, both
electromotive force and current fall off, and this may be
due to a deficiency in the quantity or flow of the sap, or
both.
As regards the constancy of these cells I am inclined to
think they must draw a positive charge from the air when-
ever their potential falls below that of the air, in the same
way as shown by the capacity tests they give off to the
air any excess of current with which they are artificially
charged. No other explanation of their long-sustained
electrical activity occurs to me, and if they are carefully
examined it will be seen that the flower or foliage end of
fruits and vegetables is not sealed so thoroughly and
effectively as the stalk or root. If that is so they are
storage cells in a new sense. In other words, they are
maintained in a state of electrical activity by the air only,
and it would not be possible, by joining them up in series,
to increase their electromotive force beyond that of the
air, because if it could be augmented and I do not believe
it can by such an arrangement, any excess of potential
above that of the air would be given off instantaneously.
We have seen that an artificial charge is retained for some
little time, but that, inevitably, the vegetable cell reverts
to its normal electromotive force and polarity.
38 ELECTRICAL STRUCTURE AND
WATER IN ITS RELATION TO PLANT LIFE.
If, as it would appear, a constant supply of electricity
from the earth is necessary to the well-being of everything
that grows therein, the fact that dry soil is a bad conductor
of electricity assumes an important aspect. In the
experiment about to be described a quantity of earth was
dug from the garden, carefully sifted and weighed, and
equal quantities were placed in three porcelain pans of
equal dimensions. These were labelled 1, 2, and 3. Nos.
1 and 2 were put in a gas oven and baked, the soil being
frequently turned over, until all moisture was expelled.
No. 1 was then protected from moisture, and after a
solution of one per cent, of ferro-sulphate had been mixed
with the soil in No. 2 it was again baked until it had become
dry ; No. 3 was left untouched.
A galvanometric test of pan No. 1 gave no deflection
whatever, whilst Nos. 2 and 3 (No. 2 being dry) exhibited
no difference in their electrical conductivity ; pointing to
the fact that, considered as an electrolyte, ferro-sulphate
was an efficient substitute for water. The next step was
to sow exactly the same weight of mustard seed in each of
the three pans, which were then placed in a room in a
diffused light with free access to the air.
No. 1. Baked dry earth.
No. 2. Baked dry earth containing ferro-sulphate,
and
No. 3. Moist earth as taken from the garden.
No. 3 was watered in the usual manner that is to say,
care was taken to keep the soil thoroughly moist but Nos.
1 and 2 were given only ten per cent., in the form of spray,
of the quantity of water accorded to No. 3.
The outcome of the experiment was that while the seed
in No. 1 did not germinate, the growth in Nos. 2 and 3
exhibited no apparent difference.
FUNCTION IN PLANT LIFE 39
Had the experiment been carried out in a frame, so that
the soil could have received its charge from the negative
earth instead of from the positive air, the results obtained
would not have been so conclusive, as percolation of
moisture from below could not have been guarded against.
As it was, one could reasonably infer that the small per-
centage of conductive mineral in the soil of No. 2 acted,
in conjunction with the water, as an electrolyte, and so
relieved the latter of part of its duties. I say in conjunc-
tion with the water, because without moisture there can be
no conductive or inductive capacity in soil or in plant life.
It would be interesting to learn whether in countries
subject to drought comparison has been made, under
similar climatic conditions, between districts where the
soil is and is not ferruginous. In Egypt the sand generally
contains some mineral salts, and a minimum of irrigation is,
more often than not, generously responded to. The
question is one of some importance, more especially in
relation to the Indian famine problem : the rice plant
requiring an excessive amount of water for its successful
cultivation.
THE EFFECT OF ELECTRICAL STIMULATION UPON GROWTH.
In A Text-book of Biology, by J. R. Ainsworth Davis,
B.A., it is said : " Electricity probably plays an im-
portaiit part in growth, as electric currents taking various
courses have been demonstrated in living plants. Currents
artificially sent through a root have been found to retard its
growth"
The sentence in italics, taken without qualification, is
I think, incorrect. It depends, in my judgment, upon the
sign of current and the electromotive force employed.
A current of positive sign applied to the root of a plant
growing in the earth might exert a retarding influence, and,
similarly, one of negative sign to the soil of a pot plant.
40 ELECTRICAL STRUCTURE AND
But given proper connections and an electromotive force
not greatly in excess of that of the earth or air, the effect
of electrical stimulus should be beneficial.
This opinion is not merely theoretical, but a result of
long-continued experiment.
Years ago I boiled one potato and baked another for
fifteen minutes and allowed them to get cold. Precisely
what had taken place I do not know, but they gave no
reversal of sign, and except that, by reason of the water in
them, they still possessed capacity were, so to speak,
electrically dead. They were then each joined up by steel
needles to a dry cell (zinc to unprolific and carbon to
prolific eye) and left for twenty-four hours, when they
were disconnected. Thereafter they not only gave perfect
reversals, but began to sprout in a quite remarkable
manner.
Another test was with tomato plants in the greenhouse.
Hypothetically a plant grown in a pot is grown under
unnatural conditions, because it is cut off from the negative
earth-current and compelled to take its root-charge from
the positive air.
I therefore planted twelve tomato plants of exactly the
same size and description in pots of equal size and with
uniform soil . Six of them were treated in the usual manner,
but the other six were connected directly with the earth by
means of stiff copper wires from the soil in each pot to the
earth beneath the slats upon which the pots rested ; all
the plants being given the same amount of water.
In the end the last-named six were infinitely more
robust and bore heavier crops than the others.
A third experiment was with two onions, neither of
which exhibited any outward sign of growth. Each of
these was connected to a dry cell (1 volt), but with
reversed connections ; the object being to ascertain what
effect, if any, the polarity of the stimulus had upon growth.
FUNCTION IN PLANT LIFE 41
The two vegetables in question are shown in Figs. 20 and
21. Steel darning-needles were again used, and by means
of these the zinc of one dry cell was connected with the
root and the carbon with the foliage end of A (Fig. 20),
while in the case of B (Fig. 21) the arrangement was carbon
to root and zinc to foliage end. Both were then left in a
room in a weak diffused light for five days and then
sketched.
The drawings are explanatory in themselves, but it is
worthy of remark that A gave evidence of growth within
twenty-four hours under what may be termed natural
stimulus, while, though it cannot be positively asserted
that in B there was a retarding influence, it appeared that
growth was not stimulated. This, in a measure at all
events, proves my point that the value of electrical stimulus
is largely dependent upon sign of current, and lends colour
to the suggestion that the employment of low electromotive
forces in agriculture and floriculture is in harmony with
natural laws.
42 ELECTRICAL STRUCTURE AND
CHAPTER III
THE EMPLOYMENT OF ELECTRICITY IN
AGRICULTURE
IT is now more than a hundred and fifty years ago
that a Scotsman named Maimbray attempted to stimulate
growth by electrifying the soil, and since then experiments
on a large scale have been and are being carried out at
Helsingfors, Brodtorp, Breslau, the Durham College of
Science at Newcastle-on-Tyne, and elsewhere ; the method
employed being high-tension electricity, usually generated,
I believe, by a Wimshurst machine or machines, and carried
by a network of bare wires strung upon insulators affixed
to poles some six feet or so in height, and covering the field
in which the vegetables are grown.
The results have occasionally, it may be frequently,
been satisfactory, but I cannot help thinking that, as a
matter of possibility, they may have been due to the
formation of nitrous oxides at the sparking points, and that
better results may be obtained by studying Nature's
methods and endeavouring in a more modest and in-
expensive way to improve upon them.
I am reminded, in fact, of high-frequency treatment of
the human body. It does not rest upon any definitely
ascertained scientific basis, and might be relegated to the
scrap-heap without injury to mankind.
While my observations upon this subject are specu-
lative, in that no experiment upon a sufficient scale has yet
been made with low-tension continuous currents, we have
FUNCTION IN PLANT LIFE 43
some evidence of their effect upon the onion when the
negative pole is applied to the root and the positive pole to
the foliage, and it should be worth while to experiment
with, say, five or ten volts similarly applied to a field of
several acres.
Another point which should not be lost sight of is that
some plants suffer from chlorosis, the disease being due to
deficiency of iron.
Now, while it is true that the atmosphere is positive and
the earth negative, it also seems that Nature seldom if ever
relies entirely upon the constant and unintermittent
maintenance of any single condition upon which life
depends, and it is quite possible, even probable, that
electrical generation goes on in the plant itself. Most, if
not all, plants contain iron, and all of them inspire oxygen ;
two elements which, in the presence of a suitable alkali
and this we know to be contained in the protoplasm are
capable of generating electricity. During periods of
drought the root- supply of current may, conceivably, be
cut off by non-conducting dry earth, and if that current is
necessary to the plant it would perish had it not any other
source of supply ; whereas so long as its protoplasm
remained in a fluid condition it would, with some measure
of independent generation, be better fitted to endure
hardship. Take, for example, the savoy cabbage. The
outer green leaves contain a comparatively large quantity
of iron (17 milligrams per 100 grams of substance), and
those leaves standing out from the closely-folded heart
of the plant would have the largest oxygen intake. It
would not be necessary for that process to extend through-
out the plant, because it could be continued from the outer
leaves by conduction and induction if for any time during
the twenty -four hours even the surface of the soil was
moistened, as by dew.
According to Sachs, chlorosis in plants may be cured by
44
ELECTRICAL STRUCTURE AND
mixing a small quantity of ferrous sulphate, in solution,
with the soil ; but even where the disease does not exist iron
should, in my opinion, be used as an electrolyte and the
result noted.
NOTE FOR GUIDANCE IN TESTING.
For everything that grows, either in the earth or in a
pot, it is only necessary to have flexible wires of low
resistance and of a sufficient length to span the space
between the galvanometer and the plant. Both wires
should terminate in two darning-needles of equal gauge and
length. One needle may be inserted in the open ground
or in the soil in the pot, and the other carefully placed in
between the lignified fibres in the venation of a leaf, i.e., in
the interspaces, or areolae, which are filled up with tran-
spiratory assimilating tissue. Contact with the venation
may introduce error, but if ordinary care is taken there
will not be any discordant result. The needles must, of
course, be kept scrupulously clean, and should not be
insulated for any portion of their length, as such insulation
a, a, a, a are the areolae. The needle should be inserted as shown.
whether by india-rubber or gutta-percha, etc. is liable
to cause confusion. Plain, clean needles, well -insulated
FUNCTION IN PLANT LIFE 45
wires, and clean ends to them will save much trouble. If
the connecting wires are of sufficiently low resistance it
does not matter whether the object to be tested is one yard
or one hundred yards from the galvanometer.
In order to make my meaning quite clear I have given
a sketch of a part of a leaf of Anihyllis Vulneraria. The
enclosed interspaces, or some of them, are those which
should be connected up, while the dark parts are those
which should be avoided.
Part II
STUDIES IN ELECTRO-PHYSIOLOGY :
ANIMAL AND VEGETABLE
CHAPTER IV
REVIEW OF ELECTRO-PHYSIOLOGICAL
RESEARCH
PUT briefly, the history of electro -physiological research is
one of contradiction, confusion, and uncertainty. To this
day the medical profession regard with a not unmerited
degree of suspicion the results and theories of those very
able men who have for the last hundred and thirty
years or so laboured in this field of scientific investigation.
Had it not been for their failure to discover certain facts
of primary importance, facts which would have made all
things clear to them, electro-physiology would long ago
have enlightened and led the world of medicine.
Later on I will give those facts the prominence they
deserve, but before doing so it may be useful to offer a
short recapitulation of what has been done.
From A Practical Treatise on the Medical and Surgical
Uses of Electricity, by G. M. Beard, M.D., and A. D. Rock-
well, M.D., I quote the following :
" Those who aspire to mastership in electro-thera-
peutics will not be content with the mere attempt to relieve
symptoms ; they will seek to study those most complex
and subtle diseases for the treatment of which electricity is
indicated ; they will resort to this force for diagnostic as well
as therapeutic aid ; they will strive to know not only
how to use it, but, what is more difficult, how not to use it.
He only can reap the full and rich harvest of electro-
therapeutical science and art who sows beside all waters ;
50 STUDIES IN ELECTRO-PHYSIOLOGY:
he must become more or less proficient in neurology, in
electro-physics, and in electro-physiology. He who has a
knowledge of the laws of animal electricity, and the actions
and reactions of franklinic, galvanic, and faradic electricity
on the brain, spinal cord, and sympathetic ; on the nerves
of motion and of common and special sense ; on voluntary
and involuntary muscles ; on the skin, and on all the
various passages and organs of the body in health, and also
of the electro-conductivity of the body, will find the paths
of electro-diagnosis and of electro -therapeutics illumined at
every step by such knowledge, and will, in the end, make
more correct interpretations of disease than he who merely
holds electrodes on patients without any higher aim ; and
more than that, he will be introduced into a field of thought
and experiment a field surpassingly rich and fruitful
and lying in close relation to all departments of physiology,
of pathology, and of biology, where he can study science
for its own sake."*
To go back to history, it was in 1786 that Galvani
discovered that muscular contraction followed the contact
of the nerves and muscles of a frog with a heterogeneous
metallic arc. He theorised, and his theory was that in the
tissues of animals there existed a special independent
electricity, which he called animal electricity. Later
observers admitted the existence of animal electricity as
a force, but explained it by contact of dissimilar substances
and by the chemical action of the fluids of the body on the
metals. This erroneous and untenable theory is upheld by
the average physiologist of to-day.
Volta's researches followed, and in 1799 Humboldt
published a work which went to show that Galvani and
Volta were both right and both wrong ; that there was such
a thing as animal electricity ; that Galvani was in error in
* The italics are iriine.
ANIMAL AND VEGETABLE 51
regarding it as the only form of electricity that appeared in
his experiments ; and that Volta was wrong in refusing to
admit its existence.
In 1803 a nephew of Galvani, Aldini, published
experiments that went to demonstrate the existence of
animal electricity. The voltaic pile, however, was a
stronger argument against the existence of animal elec-
tricity than any experiments could be in its favour, and for
these reasons animal electricity was forgotten.
The electromotive force of a voltaic pile would be,
approximately, 1 volt per cell, while that of the human
body is, also approximately, 0004 volt in its entirety. It
is difficult to see how Aldini arrived at his conclusion.
In 1827 M. Nobili, having constructed a very sensitive
galvanometer, claimed to have detected the existence of an
electric current in the frog ; a few years subsequently
Matteucci had turned his attention to this subject, but it
was reserved for Du Bois-Reymond to investigate most
clearly and most fully, if not most conclusively, the electric
properties of the nerves and muscles.
By these two observers (Matteucci and Du Bois-Rey-
mond) it was believed to have been shown
1st. That currents in every respect like the frog-
current of Nobili were not peculiar to the frog, but were
inherent in all animals, warm and cold-blooded in toads,
salamanders, fresh-water crabs, adders, lizards, glow-
worms, and tortoises, as well as rabbits, guinea-pigs, mice,
pigeons, and sparrows.
2nd. That currents are found in nerves as well as
muscles, and that both are subject to the same laws.
3rd. That this muscular current may be upward or
downward, and that the current of the whole limb is the
resultant of the partial currents of each muscle.
4th. That electricity is found not only in the muscles
and nerves, but also in the brain, spinal cord, and
52 STUDIES IN ELECTRO-PHYSIOLOGY:
sympathetic ; in motor, sensory, and mixed nerves ; in a
minute section, as well as in a large mass, of nervous sub-
stances ; in a small fibril as well as in a large muscle ; in
the skin, spleen, testicles, kidneys, liver, lungs, and
tendons ; but not in fasciae, sheaths of nerves, and sinews.
It is over one hundred years since Du Bois-Reymond
taught us this, and we have learned nothing from it.
The next prominent exponent of electro-physiology
was Dr. C. B. Radcliffe, who sought to prove that the
sheaths of fibres of nerve and muscle during rest are
charged with electricity like Leyden jars. He postulated
the theory that the sheaths of the fibres were dielectric,
but did not attempt to differentiate the" open " from the
" closed " circuits of the nervous system.
He said: "When a' nerve or muscle passes from
action to rest it resumes its condition of charge." But
" elongation, therefore, is the result of charge, and con-
traction of discharge."
This view is, of course, quite fallacious. The reverse
obtains. When an impulse is conveyed to certain groups
of sarcomeres they contract ; when discharge takes place
they elongate, and are again in readiness for charge.
Then we had Professor John Trowbridge, of Harvard
College, who cast grave doubts upon the interesting and
hitherto accepted conclusions of Du Bois-Reymond in
regard to animal electricity, and ascribed the whole
phenomena as due to the alleged fact that two liquids of
dissimilar chemical character, separated by a porous
partition, gave rise to a current of electricity. More
recently this somewhat far-fetched hypothesis of dissimilar
fluids has been substituted by two dissimilar metals ; i.e.,
electrodes ; the theory being that electrical action is set
up between two electrically dissimilar metals the elec-
trodes in the presence of an exciting liquid, such as the
secretion of the sweat-glands.
ANIMAL AND VEGETABLE 58
This, I think, brings us more or less up to date, and
leaves the so-called science of electro-physiology in a
somewhat hopeless condition. No two sets of observers
are in agreement, and, as a matter of fact, the general
medical practitioner has in his heart about as much respect
for electro-physiology as he has for manifestations of the
occult.
All this appears to be very extraordinary and difficult
of explanation. How is it that these great men of science
were not only unable to agree but really discovered very
little of service to humanity ? The reasons are not far to
seek.
In the first place they were not, any of them, trained
submarine-cable electricians, specialists in their work,
whose business it is to acquaint themselves with the
conditions under which tests of such extreme delicacy and
difficulty must be conducted. For this branch of research
a specialist electrician is imperatively called for.
The causes of the confusion, the sources of error in the
past, lie, in the main, in three factors which have never been
taken into consideration, for the reason that they were
not discovered. These three factors are
(1) The constant electro-chemical generation of nerve-
force in the human body.
(2) The presence in that body of great conductive and
inductive capacity ; and
(3) The conductive and inductive capacity of every
liquid and every moist substance or object.
Let us see how these factors come into play as sources
of error.
That the human body generates static electricity by
muscular movement is well known, but this charge can
be dissipated in a few moments by placing the body
preferably by the palms of the hands in contact with an
earth plate of low resistance. That it possesses electro-
54 STUDIES IN ELECTRO-PHYSIOLOGY:
static capacity is also known, because when perfectly
insulated the body can be charged to a high potential.
That it has inductive capacity also is not so well under-
stood.
So far as capacity is concerned, we may liken the body
to a collection of storage cells or Leyden jars, which are
liable to become more or less highly charged, or to have their
charge altered by any direct or passing current or exciting
influence, or change in exterior insulation.
Now, these storage cells or Leyden jars cannot, if they
depend for their charge upon some outside source of
energy as the exciting influence, be in a constant state of
tension, because the outside current is not always flowing
either to charge them directly or by passing in their
vicinity. We must then depend upon muscular move-
ment for the charge, and if we find, as we do find, that
movement of any kind exercises only a momentary effect
upon the human electromotive force, and that, within
limits, such electromotive force continues to be produced
even when the body is absolutely motionless, we must look
further for the source of energy.
CAUSES WHICH HAVE CONTRIBUTED TO ERROR.
We will now take the three factors I have mentioned
seriatim, but before doing so it would be well to mention
that in the majority of tests, upon which the conclusions
to be given hereafter are based, a Kelvin Astatic reflecting
galvanometer of a resistance of 88,000 B.O.T. ohms at
15 C. and perfect insulation was used. This instrument
was made for me by Elliott Bros., of Lewisham, and its
sensibility was such that a scale deflection of 400 mm.
from a central zero could be obtained with a current of
0-1 micro-ampere. (See p. 235.)
The electrodes I will describe later.
ANIMAL AND VEGETABLE 55
Now, it is quite clear that if nerve-force, or, as I prefer
to call it, neuro-electricity, is constantly generated in the
body, it must be as constantly given off, otherwise the neuro-
electrical pressure would become excessive. The absolute
insulation of the body is provided by the skin, but the skin
is not an insulator of very high resistance. Nor is its
resistance uniform, any more than the generation of
neuro-electricity is uniform in all individuals. Sign,
electromotive force, and current vary with the person as much
as height, weight, and anthropometric measurements vary.
If nerve- energy were visible we should probably see
every human being one might say every living thing-
surrounded by an aura, or neuro- electrical field, extending
some distance from the body and gradually fading into space.
We must, however, realise that the rapidity with which
that neuro-electricity can pass to earth must depend upon
the manner in which the body is protected or insulated
from the earth by dielectrics other than the skin. For
example, the insulation of a carpeted room with the win-
dows and doors closed would be infinitely higher than if
the body were exposed to the open air, or in contact with
damp earth, or with the hands touching some metallic
substance connecting with the earth. We may, in fact,
conceive many conditions in which the insulation of the
body could be increased or impaired.
In considering " air " as the normal " earth " of the
body it must not be thought that I am unsupported in the
view I have taken, although physicists may not, so far,
have fully appreciated the conductivity of air, under
varying conditions of humidity and movement, in its
relation to that form of energy called nerve-force, or even
to electricity of so low a tension as 4 or 5 millivolts.
In his Physiological Physics M'Gregor-Robertson, who
will be remembered in connection with the University of
Glasgow, says : " A charged body in a current of air slowly
56 STUDIES IN ELECTRO -PH YSIOLOG Y :
loses its electricity by convection. Particles of the air com-
ing in contact with the body receive a charge, and pass on,
to be succeeded by other particles, each of which carries
off its portion, till the whole charge is thus dissipated."
Dissipation by convection does not fully explain the
phenomenon. Hot air, inferentially, is dry air, and dry
air is a bad conductor. All the neuro-electricity given off
in a room does not, therefore, form a stratum near the
ceiling, and a " current of air "may be variously construed.
Anyone moving about in the testing-room, draught from
the door, window, or floor, or even the breath of the persons
present may create such a current. In any case, however,
the air is an" earth " of high resistance, and the higher its
resistance dimensions being equal the quicker the at-
mosphere of the testing-room will become charged with
neuro-electricity, because of the increased difficulty placed
in its path to a true " earth."
That being so, it is evident that while the generation of
neuro-electricity in the body might be deemed to be
constant, the dissipation of it cannot be so by reason of the
varying conditions of exterior conductivity.
Another important point to remember is that the sign
of current in individuals is not always the same. The
palms of the hands, being free from sebaceous glands, are
the most convenient body terminals, but, until determined
by test, the body resembles a galvanic cell whose terminals,
electromotive force, and internal resistance are unknown.
The bearing of all this upon error will soon become
apparent. Let us imagine ourselves in a laboratory, the
floor and walls of which oppose considerable resistance to
the escape of electricity, and let there be two people
reproducing, say, the experiments of Professor Trowbridge.
We, however, will take the precaution of testing
them for personal neuro-electricities, and, to quote figures
obtained in actual practice, say that A gave a deflection
ANIMAL AND VEGETABLE 57
of 2000 mm. positive and B of 40 mm. negative upon the
scale of the galvanometer I have mentioned. After about
an hour, or less (according to the size of the room), the air
of the laboratory would become charged by reason of the
neuro-electricity emanating from the persons of A and B,
and as 200 positive minus 400 negative = 200 negative,
the air must become negatively charged, increasing in
tension or pressure with time or varying with any alteration
in the insulation.
In this we have one of the sources of error. The tension
and sign of the atmosphere in the testing-room have
always been unknown quantities.
PERSONAL CAPACITY
I have not of recent years taken any actual measure-
ments, but the mean of a former series of tests gave
nearly four microfarads as the average capacity of
the body. Now if B (= 400 mm. negative) touched A
( = 200 mm. positive), A would become 200 mm. negative
so long as he remained shut up with B, or, failing direct
contact between the two, the air of the room would
charge A as certainly as water would find its level. In-
ductive capacity introduces another and equally per-
plexing source of confusion, as a flash of lightning, a
powerful earth-current, wireless telegraphy, or the proxi-
mity of a charging station or of an electric railway or tube
would not only affect the persons experimenting, but also
the subject of experiment, although a galvanometer of
the d'Arsonval type might not be perceptibly influenced.
CAPACITY OF LIQUIDS AND MOIST SUBSTANCES
But that is not all. Physiologists, overlooking conductive
and inductive capacity, have invariably used what they call
non-polar isable electrodes, or contacts to which the objects
under examination are connected, for the purpose of
58 STUDIES IN ELECTRO-PHYSIOLOGY:
conveying the currents of electricity supposedly emanating
from them to the coils of the recording instrument. These
electrodes were, and are, moistened with some liquid, and
as all moist substances absorb electricity as a sponge
absorbs water to the limit of its capacity, it follows that
unless each electrode is of exactly the same area and
density, there will be a controlling current from one of the
two. It also follows that if one electrode has a thousandth
part more moisture than the other, an opposing electro-
motive force, so to speak, may be exerted by it, and
furthermore, disregarding minor details, those electro-
motive forces would be liable to variation from time to
time by
(1) The number of persons present in the laboratory ;
the length of time they remained there, and their
respective neuro-electrical signs and electro-
motive forces.
(2) The nature of the liquid or liquids employed.
(3) The degree of absorption.
(4) The area of the electrodes ; and
(5) The amount of moisture present in the object or
subject under examination.
Let us suppose A and B to have been experimenting
with a piece of excised muscle in a moist condition and to
have obtained certain data. Their results woyld always
check, because the muscle would invariably have a charge
equal to 200 mm. negative.
Two other persons, C and D, question the accuracy of
the published results of A and B, and proceed to verify or
disprove them. C, let us say, = 300 mm. positive and
D 150 mm. negative. The resultant charge would, of
course, be representative of 150 mm. positive, the muscle
would be differently electrified, and the data obtained could
not agree with the results of A and B. In the same manner
E and F may prove both A and B and C and D to have
ANIMAL AND VEGETABLE 59
been hopelessly incompetent, and in their turn be subjected
to similar criticism at the hands of others.
As a great deal which does not happen to be true has
been written about non-polarisable electrodes, it may be
well at this juncture to give an account of a few experiments
which were carried out with the object of exploding some
cherished theories.
I found that when two wires of equal gauge and length,
soldered to two steel needles of exactly the same gauge
and length, were connected to the terminals of the gal-
vanometer, and the needles were inserted in various objects
and liquids, certain deflections were observed deflections
which were not momentary, but more or less constant.
These deflections are explained as being due to galvanic
action.
There are two theories, i.e.
(1) Two metals that is to say, one electrode being
electrically positive to the other in one solution,
or
(2) One metal in two solutions.
It will, however, be only necessary to consider the first
seriously, inasmuch as there cannot be two different fluids
in distilled water, while the most careful analysis has
failed to reveal the presence of two widely differing solu-
tions in the juices of fruits and vegetables. Nor can the
first hypothesis be sustained, if only for the reason that the
sign of the deflection obtained is not altered by the reversal
of the needles upon the terminals of the galvanometer.
In the case of liquids such as distilled water, and all
lifeless moist objects, the deflections given by them must
be of the same sign, and that sign is, and must be, governed
by the sign of the electricity or neuro- electricity with which
the air of the testing-room is, for the time being, charged ;
that is to say, when the two wires and electrodes are of the
same metal and of equal resistance, the deflections which
60 STUDIES IN ELECTRO-PHYSIOLOGY:
occur are always ascribable to charge imparted by some
source or vehicle of energy to the article under examination.
As I have before remarked, it is owing to this fact, and
to the further important truth that all fluids and moist
objects possess conductive and inductive capacity, that the
results obtained by various investigators have so materially
conflicted.
But when under the same conditions we test anything
in which there is life, we have different factors to deal with.
In the section upon Electrical Structure and Function
in Plant Life I have given a summary of some ten thousand
tests of fruits and vegetables in which I used steel darning-
needles as the electrodes, but one or two of them may be
repeated here.
First theory : Take two equal lengths of insulated
flexible copper wire and solder to each length a steel
darning-needle, connecting the other ends to the terminals
of the recording instrument. Call the needles R and L
respectively.
Now select a sound onion and insert the R needle in
the root, and the L needle in the foliage end. Upon
depressing the galvanometer short-circuit key a constant
negative deflection will be observed. Theoretically, there-
fore, the L needle is electrically positive to the R needle,
and the juice of the onion being the exciting liquid galvanic
action is set up. If that is so, and if we do not reverse the
connections, the polarity of the needles is established, and
we must continue to get a negative deflection, no matter
where we insert the needles. If, however, the onion is
reversed, so that the R needle is in the foliage end and the
L needle in the root, there will be an equally constant
positive deflection, showing that the difference in polarity
is in the vegetable, and not in the needles.
Again, take two suitable electrodes, say two silver rods
6 in. by f in., provided with terminals ; attach them to
ANIMAL AND VEGETABLE 61
two equal lengths of wire and connect as before. Hold the
R electrode in the right and the L electrode in the left hand,
being careful that the pressure is equal. The sign of the
deflection is, we will say, positive. It follows, therefore,
that the R electrode is electrically positive to the other.
Leave the connections unaltered, but hold the R electrode
in the left and the L electrode in the right hand. If the
polarity is in the electrodes the sign of current will be the
same. But it is not. The deflection will be negative,
because polarity is in the hands and not in the electrodes.
In this connection proofs can be multiplied almost ad
infinitum, but I do not wish the case to rest upon my
unsupported testimony.
In an article in the Lancet of January 13, 1917, Dr.
C. Nepean Longridge, F.R.C.S. Eng., M.R.C.P. Lond.,
who has been examining and treating various cases on my
principles for some two years, says
" Experiment 1. With the aid of Miss Flecker, at the
Ladies' College Physical Laboratory, Cheltenham, I
estimated the electrical resistance of a piece of oak-tanned
sole leather 3 in. long by 1 in. wide. We found that when
dry the resistance was practically infinity. When wet the
resistance is that of the fluid the leather has soaked in.
" Experiment 2. One pole of the galvanometer was
connected to an electrode which could be held in the hand.
The other pole was connected by an insulated cable to a
copper plate imbedded in the earth. Another insulated
cable was connected at one end to the metal pipe supplying
water to the house, and at the other end to a brass rod of
1 in. section. After earthing myself I held the brass rod
in one hand and the electrode in the other, and obtained a
rapid off-scale deflection, showing, firstly, that an electric
current was coming from my body ; and secondly, that the
earth connexions were working properly, for the current
passed out by one hand through the brass tube to the
62 STUDIES IN ELECTRO-PHYSIOLOGY:
water-pipe, thence about 20 ft. through the earth to the
copper plate, and through the galvanometer to the other
hand, so completing the circuit.
" Experiment 3. The brass tube was then laid on the
floor, which was covered by a thick carpet. I held the
electrode by one hand and put both feet on the brass
tube. I wore ordinary boots, which were dry. No deflec-
tion was obtained, because the dry leather soles of my
boots insulated me from the earth. I then took my
boots off and put my bare feet on the tube and obtained
an off-scale deflection.
" Experiment 4. Next day was wet, and I walked about
half a mile, so that the soles of my boots, which were free
from holes and metal nails, became wet. On holding the
electrode in one hand and placing my feet on the brass tube
a rapid off-scale deflection occurred, showing that current
was passing through my boots to earth.
" Experiment 5. The pole of the galvanometer con-
nected to earth by the copper plate was disconnected. It
was reconnected to a hand electrode exactly like the one
previously used, so that the galvanometer was now con-
nected to the hand electrodes only. After the necessary
earthing process, I held the electrodes in the hands and
obtained a deflection which remained steady at 170 mm.
I then placed my feet, still in wet boots, on the brass tube
and awaited results. The light on the scale very slowly
began to recede towards zero. I repeated this experiment
several times. The light never remained at zero, but if it
got as far went over to the other side of the scale, and
generally registered 40 to 60 mm. I take this as evidence
that electricity was gradually leaking out of my body to
earth, through my wet feet. One would not expect the
light to register zero, as there is a continuous generation of
electricity in the body. In view of these experiments,
the grandmotherly advice we have so often received, not
ANIMAL AND VEGETABLE 63
to stand about in wet boots, takes on a new and important
significance which ought to claim our belated respect.
They also, to my mind, afford evidence that trench foot is
probably caused by long-continued leakage of electricity
from the feet."
In regard to experiment 2 it may be urged by the
supporters of the difference in metals theory that it does not
present any new feature, while the fact of there being no
deflection in experiment 3 can be explained by the absence
of moisture at one pole, and therefore of the improbability
of galvanic action taking place. Experiments 4 and 5,
however, are, to my mind, quite at variance with that
theory, and appear to negative the conclusions of those
who have been and are responsible for it.
In my work upon Electro-Pathology and Therapeutics
I stated that the thumb of each hand was of opposite sign
to the fingers of each hand and carried a greater quantity
of current.
Dr. E. W. Martin, who has had some few years' ex-
perience of my methods, has sent me the results of a series
of tests carried out by him, and gives his conclusions as
follows :
" It would therefore appear that
" (a) There is no electrical current generated by two
metals in contact, even in the presence of moisture.
" (b) A current passes when both hands are in contact
with both electrodes.
"(c) That different conducting substances act differ-
ently in their relation to the body current.
" (d) That the current cannot be due to the moist skin
and metal only, as we find that in a complete
circuit from skin and metal to skin and metal
no current is set up so long as one hand only is
used.
" (e) That the thumbs appear to be electrically as well
as anatomically in opposition to the fingers of the
64 STUDIES IN ELECTRO-PHYSIOLOGY:
same hand, and equally in opposition to each
other, and that they appear to form terminals of
a circuit with the fingers of the same hand, as
when the thumb is brought into contact a current
at once passes.
" (/) That the approach of the thumb to the electrode,
even without contact, produces a slight deflection
which is probably not static, as the deflection
remains after all movement, so far as it can be
controlled, has ceased."
The main points touched upon by Dr. Martin, i.e.
(1) That unless both hands are used the contact of
skin and metal will not exhibit electrical action,
and
(2) That the thumbs are of different sign to the
fingers
may be very simply and conclusively proved in the follow-
ing manner :
Take two electrodes, of the same size, of copper, silver,
or German silver, and connect them by two wires of equal
gauge and length to the terminals of the galvanometer.
Insert one of these electrodes between the first and second
and the other between the third and fourth fingers of the
left hand, and do not allow them to touch. No deflection
will be observed unless the hand is wet. In that case there
may be a slight leakage from the thumb. Then bring the
left thumb into contact with one of the electrodes and a
deflection will at once ensue. Repeat the experiment
with the right hand and the result will be the same, only
that the deflection ultimately obtained will be of opposite
sign.
This experiment as conducted by Dr. Martin is thus
described by him
" (a) One electrode was placed between the third and
fourth fingers, the other electrode between the
first and second fingers of the left hand ; not
allowed to touch each other. Key closed, i.e. 9
ANIMAL AND VEGETABLE 65
Circuit from skin and metal, through galva-
nometer, to skin and metal. Deflection, nil.
" (b) Repeated with right hand. Deflection, nil.
" (c) Terminals allowed to touch. Deflection, nil.
" (d) Same position electrodes, left hand. Thumb
approximated to electrodes. Deflection, slight.
Thumb touching negative pole electrode. Deflec-
tion, negative. Thumb touching positive pole
electrode. Deflection, positive.
" (e) Same experiment repeated with right hand and
right thumb gave a reverse result, i.e.,
_j- pole deflection negative,
pole = deflection positive."
In order to reconcile these results with the views of
physiologists we should have to assume
(1) There are no sweat-glands in or moisture upon the
fingers of either hand, and
(2) That the thumbs only contain sweat-glands or
exhibit moisture, and that their secretion or the
moisture is of so opposite a character, chemically,
as to instantly change the polarity of the elec-
trodes touched by them.
No comparison is possible between the currents set up
by a galvanic cell and those emanating from the human
body. The former is a simple generator of electricity ;
the latter a complex system from which electricity or
neuro-electricity is constantly bemg given off. It is only
necessary to establish a difference of potential at two
points in one or more bodies to obtain deflections, due to
direct or derived circuits. Owing to the absence of
sebaceous glands in them, the palms of the hands and soles
of the feet are, no doubt, the natural " earths " of the body,
but nerve-energy must escape, to a greater or lesser extent,
from every square inch of the skin.
Again, examine, galvanometrically, by means of the
hand-to-hand deflection, a number of persons until three
F
66 STUDIES IN ELECTRO-PHYSIOLOGY:
are found who yield a positive and three a negative re-
action. If the observer himself is of positive sign two
other positives only will be required, and vice versa. Then
let the testing-room be vacated for several hours and freely
ventilated.
As a next step introduce each of the persons selected to
the testing-room, one by one, " earth " the subject for five
minutes, and take the hand-to-hand deflection very care-
fully, noting the sign and number of millimetres and
ushering the subject from the room before the next one is
admitted.
Let us assume that the deflections are respectively as
follows :
Observer = 250 mm. positive
First subject = 200
Second ,. = 225
Third = 250 negative
Fourth -200
Fifth =225
These figures might not actually obtain in practice,
but they will serve to illustrate my meaning and are
sufficiently near to the truth.
Having registered the above data, let the observer and
the five subjects assemble in the testing-room and remain
together for a few hours, the length of time being dependent
upon the size of the room and its insulation from the earth.
If it is of moderate dimensions, carpeted, and with doors
and windows closed, two hours should be sufficient. Then,
without earthing and without anyone leaving the labora-
tory, take the hand-to-hand deflections again, in the same
order.
Now, if the differences in polarity and in the number of
millimetres exhibited by the subjects are due to dis-
similarity of metals, acted upon by different secretions of
the sweat-glands, the deflections should be as before,
ANIMAL AND VEGETABLE 67
though there might be variations of a few millimetres due
to increased or decreased moisture or pressure of one or
other of the hands. If, however, my contention be correct
that we give off neuro-electricity to the air in accordance
with our respective sign and electromotive force, and
that the body is liable to be inductively influenced, it is
obvious that a common level would, in time, be found, and
that the resultant hand-to-hand deflection of each and
every one of the persons present must be in the neighbour-
hood of zero.
That is what actually happens.
I read somewhere, but regret the source is not given in
my notes, that we may consider as generators of energy a
liquid passing from a higher to a lower level ; heat passing
from a hot to a cold body ; electricity flowing from a body
with a high potential to one with a low potential ; move-
ment transmitted from a body animated by velocity to
another with less velocity, etc. Thus energy depends on
the state of the bodies in presence. There is only an
exchange between them if they are out of equilibrium ;
that is to say, if they possess different tensions. One of the
bodies present then loses something which it yields to the
other until their tensions are equalised.
We are well aware that when two pieces of the same
metal are placed in a solution in a circuit in which a current
of electricity is flowing electrolytic action will be set up.
Polarisation is the inevitable consequence of any such
combination. But when we are calculating forces it
behoves us to take into consideration the difference
between a steam-hammer and a tack-hammer ; to
discriminate between a hurricane and a zephyr. In a
single dry cell a force of 1,500 millivolts is evolved ; the
human machine is driven by 5. Moreover, the electrodes
used by me for body-testing are of German silver, heavily
coated with chemically pure silver, and as they are all
68 STUDIES IN ELECTRO-PHYSIOLOGY:
electro-plated at the same time in the same vat and with
the same metal, the possibility of any dissimilarity is
reduced to a minimum. Furthermore, contact with the
body is not made for a sufficient time for polarisation to
occur. In addition to that the conditions are not identical.
In a galvanic cell or battery there are only two terminals,
positive and negative. In the human hands there are four
terminals a positive and negative to each hand and this
would again tend to check polarisation, even with inferior
electrodes.
With these observations it may safely be left to the
impartial reader to hold the scales between physiologist
and physicist. I have laboured the point at length
because it lies at the root of the whole matter. This, as I
believe, untenable theory of two, alleged, dissimilar metals
in the presence of moisture has not only hampered progress
during the past century, but is even now being put forward
to bar our way to enlightenment.
The second theory that of one metal in two dis-
similar solutions is, I venture to think, sufficiently
disposed of by the electrical response of earth-grown
and pot-grown plants and fruits, and calls for no further
remark.
Suggestion. In much the same way that the average
cable electrician has been accustomed to attribute certain
galvanometric deflections to " leakage," some physiologists
seek to find in " suggestion " an explanation of many of
the proofs of successful treatment which have been brought
forward. In taking cardiograms by means of the string
galvanometer psychological influences cannot be dis-
regarded, because the heart can be psychologically in-
fluenced through the cardiac branches of the vagi, but, by
my method of testing, the deflections registered by gal-
vanometers of the Kelvin or d 'Arson val type are only
subject to variation by differences of pressure upon the
ANIMAL AND VEGETABLE 69
electrodes, which by bringing conductors nearer to the
surface of the skin lower the skin resistance.
Hand-to-Hand Deflection and Thumb Pressure. The
importance of the hand-to-hand deflection, as being the
measure of the electromotive force exerted in the body at
the time of testing, is fully treated in the chapter upon
Ohm's law and electro-diagnosis, but it may serve a useful
purpose to explain what happens when there is inequality
of pressure of the two thumbs. The body is connected in
the galvanometer circuit by means of two suitable metallic
electrodes, grasped in the hands, and a certain deflection is
obtained. The thumbs carry a greater quantity of
current than the fingers, so that if one is pressed harder
than the other the deflection is altered, while if one thumb
is relaxed and the other pressed down there may even be
a reversal of sign, because the direction of current is
determined by the path of least resistance.
Even some electricians of my acquaintance find this
difficult to understand. They are accustomed to reason
in terms of bare wires, and forget that the wires or con-
ductors of the thumbs have an outer coating, or absolute
insulation, of 5,000 or more ohms resistance, in the skin.
Suppose this resistance to remain unimpaired upon one
thumb and even partly removed from the other, and the
path of least resistance becomes obvious. If, however,
polarity was in the electrodes and not in the hands, no
reversal of sign could be brought about by such difference
of pressure.
A simple diagram will explain the differences of thumb
pressure.
Let the body be represented by a source or sources of
electrical energy, the arms by two coils of equal resistance,
and the thumbs by two variable resistance-boxes, a and b.
The quantity of current arriving at points c and d will be
exactly equal, because, finding two paths of the same
70 STUDIES IN ELECTRO -PH YSIOLOG Y :
resistance, the current will divide at the battery terminal,
and if a and b are exactly balanced (no matter what
their resistance) no current will pass through the gal-
Fig, i.
vanometer. If, however, a was less than b there would be
a transfer of part of the current from d to c, and vice
versa.
Taking what should be, but is not, the science of
electro-physiology as it is to-day, it is a matter of infinite
wonderment to me that physiologists have all failed to
recognise, from their own works, that the structure of the
body is primarily electrical. If it is so one cannot be
surprised, in the absence of such recognition, that the
practice of electro-therapeutics is empirical. A necessary
preliminary to curative treatment is knowledge of the
human neuro-electrical system the generator or genera-
tors of nerve-force, the natural conductors and dielectrics,
the condensers and storage cells and their capacity, and,
what is of paramount importance, the influence of disease
upon any or all of them. Until that knowledge is acquired
treatment cannot be said to rest upon a scientific basis.
I do not, of course, include the surgical uses of electricity
ANIMAL AND VEGETABLE 71
of high potential, but I do most emphatically refer to high
frequency except as a species of electro-massage to local
and general faradisation, to central and local galvanisation,
and the rest of it. I also venture the opinion that we know
next to nothing of the electro-pathology of disease, that
we have no recognised method of electro- diagnosis worthy
of the name, and that by reason of the errors of the past
and the consequent unreliability of the data already
obtained, we should lose little or nothing if we forgot
everything we had learned, and made a fresh start under
improved conditions of research.
Let us examine, in the light of what we claim to be the
discovery of a fundamental truth, structures of the body
as illustrated and described in modern and accepted works
upon Histology and Physiology, and see what we can learn
from them.
With the evolution of body organs and structures, the
electrician has no concern and can pretend to no knowledge.
That is not his department. He can only examine them
in their completed condition, interpret them as they appear
to him, and give such explanations of their construction
and functions as are consistent with established physical
laws. If his conclusions are based upon truth, and not
upon mere theory or sophistry, they should not, cannot,
conflict with any established law, but must serve to make
clear that which is at present obscure.
As a first step we should, I think, consider the nature
of the nerve-current. To this day no one knows whether
in a galvanic cell electrical begets chemical action, or
whether the force we call electricity is generated by
chemical decomposition. There is nothing in the form
and appearance of the galvanic cell to afford the proof or
even to guide us to definite opinion. That is not so with
the human body ; we are not at that disadvantage. To
the careful observer the structure of the human body must
72 STUDIES IN ELECTRO-PHYSIOLOGY:
appear to be primarily electrical and to be designed for
the performance of electrical functions, not necessarily
outweighing in importance those chemical changes
which are essential to life, but taking precedence of
them.
ANIMAL AND VEGETABLE 78
CHAPTER V
THE NATURE OF THE NERVE IMPULSE
'* It may be supposed that some electrical function is exercised by
oxygen in the blood." Sir Humphrey Davy.
THE controversy which arose years ago between the
physiological and physical schools as to the nature of the
nerve impulse has, so far, contributed nothing decisive
to our knowledge of the subject.
" Theories there are in plenty, but none of them
adequate to explain the phenomenon." (Halliburton,
1915.)
The facts which, we are told, make a chemical theory
acceptable are
" (1) Analogy with muscle, where the propagation of
the muscular impulse is undoubtedly largely due
to the propagation of chemical disturbance.
" (2) Evidence that the nerve does undergo metabolic
changes, as shown by the necessity for oxygen,
and the production of minute amounts of carbon
dioxide.
" (3) Arrhenius and Van't Hoff showed that a rise of
10 in temperature increases the velocity of a
chemical reaction to two or three times its original
rate. . . . Maxwell's recent experiments show
that a rise of 10 C. approximately doubles the
velocity of nerve conduction. . . . Woolley ob-
tained the same figure from the influence of
temperature on the rate of conduction in muscle,
so probably the conduction process is of a similar
nature in both tissues." (Halliburton, 1915.)
74 STUDIES IN ELECTRO-PHYSIOLOGY:
All this is in perfect harmony with the hypothesis that
the impulse is neuro- electrical. The effect of a rise of
temperature upon liquid or semi-liquid conductors is to
decrease their resistance, or, in other words, to increase their
conductivity. It is purely to my mind a question as to
which action is precedent, the electrical or the chemical,
and I do not think that anyone can, after careful study of
the structure of muscular tissue, ganglia, and nerve, doubt
that it is the electrical.
The physical theories in relation to this question
compare the nerve impulse to the way in which an electrical
charge is propagated along a wire, and, in refutation, the
slow rate of conduction in nerve and the phenomenon o f
inhibition are adduced.
Now, it is incontrovertibly true that nerve-current will
flow along a metallic conductor, but it is abundantly
evident that instead of being homogeneous, as a wire is,
the conductors of the body are complex. Halliburton
tells us that a nervous impulse does not necessarily travel
along the same nerve-fibre all the way, and that there is a
system of relays. He adds that on the onward propagation
of a nerve impulse through a chain of neurons its passage
is delayed at each synapse, " hence there is additional
4 lost time ' at each of these blocks." And there are very
many of them.
Suppose that, instead of an electric circuit being com-
posed of an insulated cable, it was made up of thousands of
cables and wires and many thousands of condensers of
varying capacity. Would the velocity of the current be
the same ? It would not. There would, inevitably, be
some " lost time " at many of the condensers by reason
of their not receiving instantaneously their full tension
charge, and owing to varying degrees of retardation.
To postulate that the nerve impulse is not of an elec-
trical nature is to accuse Nature of introducing into the body
ANIMAL AND VEGETABLE 75
certain processes which are useless to man ; I refer to
insulating processes. If their existence is disputed, I can
only reply that proof of their presence is to be found in
recognised works on Physiology. Let me make that clear.
Assume that we do not know anything about the nature of
the nerve impulse, and consider only the behaviour of
nerves under electrical stimulus or irritation. My authority
is Professor Rosenthal, who, in his Physiology of the
Muscles and Nerves, writes as follows : "If the main
stem of a nerve is irritated by electric shocks, all the
fibres are invariably simultaneously irritated. On tracing
the sciatic nerve to its point of escape from the vertebral
column, it appears that it is there composed of four distinct
branches, the so-called roots of the sciatic plexus. These
rootlets may be separately irritated, and when this is done
contractions result, which do not, however, affect the whole
leg but only separate muscles, and different muscles
according to which of the roots is irritated. Now, as the
fibres contained in the root afterward coalesce in the sciatic
nerve within a membrane, it follows that the irritation yet
remains isolated in the separate fibres and is not imparted
to the neighbouring fibres, ^ihis statement holds good of
all peripheric nerves. Wherever it is possible to irritate
separate fibres the irritation is always confined to these fibres
and is not transmitted to those adjacent." *
Now, the sciatic nerve is composed of a number of
bundles of nerve-fibres (some efferent, some sensory). If
each one was not separately insulated it would be im-
possible to irritate one fibre electrically without simul-
taneously irritating all the others. Not only is this so, but
each bundle is protected from inductive interference by a
lymph space directly under the perineurium and cor-
responding to the copper taping of telephone or telegraph
* The italics are mine.
76 STUDIES IN ELECTRO-PHYSIOLOGY:
conductors. Of what use is all this if nerve impulse is not
of an electrical nature ?
Professor Rosenthal admits that the nerve substance
offers resistance to the passage of the nerve impulse. He
says : " It is probable that the propagation proceeds at
first at a greater and afterwards at a less speed," basing
this opinion upon Munk's experiments. " Its propagation
is gradually retarded. . . . From this it may be inferred that
a resistance to the transmission exists within the nerve,
and this gradually retards the rate of propagation."
Reverting to the question of peripheric nerves, he goes
on to say that transmissions or irritation from one fibre
to another occur within the central organs of the nervous
system. " But in these cases it can be shown with great
probability that the fibres not only lie side by side, but
that they are in some way interconnected " (ganglion-cells
or synaptic junctions) " by their processes. In peripheric
nerve-fibres the irritation always remains isolated. Their
action is like that of electric wires enclosed in insulating
sheaths. One of these nerves may indeed be compared to
a bundle of telegraph wires, which are protected from
direct contact with each otheif *f y gutta-percha or by some
other substance. The comparison, however, is but super-
ficial. No electrically isolating membrane can really be
discovered in any part of the nerve-fibre, but all their parts
conduct electricity. When, as we shall find, electric
processes occur within the nerve, these standing in definite
relation to the activity of the nerves, we must assume that
isolation as it occurs in the nerves is not the same as in
telegraph wires. We cannot trace the matter here further,
but must accept the fact of isolated conduction as such,
reserving its explanation for a future occasion."
Its explanation does not appear to me to present any
feature of difficulty. The endoneurium of a nerve-fibre
and I am adhering to the sciatic nerve may be said to
ANIMAL AND VEGETABLE 77
correspond to the gutta-percha covering of the telegraph
wire, but in the case of the telegraph wire as in the nerve-
fibre no electrically isolating membrane really exists ; all
their parts conduct electricity, and conduction is merely a
matter of degree. A*substance which will not conduct low
tension may be an excellent conductor of high-tension
electricity, and there is an enormous difference between the
human electromotive force of four or five millivolts and
the voltage of an induction shock.
As regards electric processes occurring within a nerve
we have in a nerve the process of intra-cellular action,
which does not take place in a wire in the same way or to
anything like the same extent, even if it occurs at all.
There are many points of similarity between nerve-
circuits and telegraph-circuits, but the two are not identical.
In regard to inhibition it is at least conceivable that by
the action of certain ganglion-cells an opposing E.M.F. is
set up in or communicated to a nerve-fibre or fibres so as
to produce a lessening of action or diminution of impulse.
It is known that " an impulse will in some cases travel
both ways." This would necessarily occur in a circuit in
which there was inductive capacity, and a mere cursory
examination of such physiological diagrams as show the
direction given to nerve impulses by different combinations
of ganglion-cells in sensory and motor paths should
sufficiently convince the student that such action does
occur.
Macdonald reduces the phenomenon of nervous con-
duction to electrolytic dissociation and association of
inorganic ions, but I fail to see how this can be caused
by potassium salts in organic combination within the axis
cylinder, as suggested by him, though some such action
may occur within a cell. A more reasonable explanation
is electrical action set up between oxygen and some
eiement electro-positive to it in the cell contents.
78 STUDIES IN ELECTRO-PHYSIOLOGY:
44 It is interesting to state, if only in outline, the kind
of theories which are in the air at present. We must
await with patience to see whether they or any of them
contain a germ of truth, or whether, like so many theories
in the past, they will be forgotten in the future." (Halli-
burton, 1915.)
That is tantamount to a confession that the chemical
theory is not altogether satisfying. Once, however, we
understand the law, our knowledge of the full application
of it will only involve some further microscopic and
galvanometric research, with our eyes wide open, to find
the something which exists but which we have not seen,
for the simple reason that we have not been taught to
look for it.
In regard to the analogy with muscle it must, I think,
be admitted on the face of the evidence I shall bring
forward that the structure and operation of voluntary
muscular fibre offers a very strong proof that muscular
impulse is primarily due to the propagation of neuro-
electrical, and not chemical, disturbances. I cannot, in
fact, find any physiological argument which is not more
in favour of electrical than of chemical action. Explana-
tion of the latter is often laborious and unconvincing,
whereas the former is always and in every detail
harmonious.
The velocity of the nerve impulse in man is said to be
about 120 metres per second. Now, the apparent velocity
of an electrical current is diminished more or less in pro-
portion to the capacity of the circuit ; the higher the
capacity the lower the velocity, due to retardation.
A cable is a homogeneous structure, in the sense that in the
circuit of which it forms a part there are no, or very few,
" synaptic junctions " to occasion delay.
In the human body the velocity of the nerve impulse is
not everywhere the same, nor could it be so unless the
ANIMAL AND VEGETABLE 79
inductive capacity was uniform throughout, and this,
obviously, is not the case.
Retardation, or the portion of the current retained upon
the surface of the wire, is also dependent upon, among
other things, the length and diameter of the wire or, in
other words, upon its resistance. And here note should
be taken of the fact that the effect of capacity is to produce
prolongation at the end as well as retardation at the com-
mencement of a current ; so that a current takes longer to
leave the line than it did to enter it.
" In nerves," I learn from Landois and Stirling, " the
resistance is two and a half million times greater than in
mercury, while in animal tissues it is almost a million times
greater than in metals." Taking the specific resistance of
copper as 1, mercury (at 57) is approximately 50, so that
the resistance of the nerve, taken longitudinally, would be
50,000 times greater than that of copper. For liquids the
resistances are enormous as compared with metals, and
they are subject to chemical decomposition or change in
the process of conduction.
It is, of course, extremely difficult, if not impossible, to
calculate accurately the resistance of a living nerve
relatively with that of a copper wire unless we are given the
exact sectional area of the nerve-conductors, and, pro-
bably, not even then. But for curiosity's sake it may be
well to see how the 50,000 times increase of resistance
works out.
We will take two round pure copper wires of sectional
areas of 0-01 and 0-02 in. respectively, and suppose them
to be two nerves of the same diameter.
The resistance of a copper wire of 0-01 in. corrected to
100 F. is 0-3677 ohm per metre, and if we, for convenience
of calculation, take the maximum length of a nerve to be
2 metres, we have 0-3677 X 2 x 50,000 = 36,770 ohms
as its total resistance, or -f- 6'5 = 5,657 ohms per ft. length
80 STUDIES IN ELECTRO-PHYSIOLOGY:
Similarly the wire of 0-02 in. section with a resistance
of 0-0884 ohm per metre would give us 8,840 ohms total
resistance and 1,360 ohms per ft. length, and while this
brings us no nearer to the actual resistance of a nerve, it
approximates somewhat to the resistance of the hand-to-
hand circuit, in which, by reason of the absence of sebaceous
glands in the palms of the hands, skin resistance is much
lower than in most other parts of the body.
This conclusion is arrived at in the following manner :
Upon the scale of a reflecting galvanometer which has a
sensibility of 4,000 mm., at a metre distance from the scale,
per micro-ampere, the average hand-to-hand deflection 01
a person in normal health is between 300 and 400 mm.,
equivalent to a current of from 0-08 to 0-1 micro-ampere.
The mean of several thousands of tests has shown the
electromotive force of man to range between 4 and 5
millivolts, and, as C = ^, we can, knowing C and E, cal-
culate R with some approach to accuracy. By this
method we should find the resistance of the hand-to-hand
circuit to be over 5,000 ohms, taking into considera-
tion the difference of sensibility or response to current
and voltage. The calculation, however, is not given with
the confidence that would attach to a bridge test in
which the natural current was used, to the exclusion of
battery power.
5,000 ohms would be lower by 3,840 ohms, or 590 ohms
per ft. length, than the wire of 0-02 in. sectional area, but
in the circuit in question there are several conductors, and
among them the main leads of the thumbs.
The resistance of nerves, whatever may be their
expression in ohms, must vary in many parts of the body,
and, irrespective of the surface area of the conducting
plates or discs or rods of the body condensers, have the
effect of altering capacity ; while further variations are
introduced by the inconstancy of the human electro- motive
ANIMAL AND VEGETABLE 81
force and differences in the nature or chemical compo-
sition of the insulating substance.
Even when in two condensers the conducting plates
are of equal surface- area, are equidistant, and E.M.F. is
constant, it does not follow that their capacity will be the
same. Suppose the dielectric of one to be paraffin and of
the other gutta-percha. The specific inductive capacity of
air being taken as 1, paraffin is 1-99 and gutta-percha 4-2.
It will, therefore, be seen that upon charging these two
condensers to the same potential difference the condenser
with the gutta-percha dielectric will receive a charge about
2-1 times greater than the condenser with the paraffin.
Moreover, capacity depends also upon the thickness of the
dielectric, in the inverse ratio.
As regards a comparison of the capacity of the human
body with that of a submarine cable, the average capacity
of the latter ranges at about 0-3 microfarad per knot,
while I have found the former, using the same battery-
power, to be nearly 4 micros. Its absolute insulation
resistance is, however, comparatively low, and charge is not,
therefore, retained.
I extract the following from one of my old note-books :
" When the body was charged for fifteen seconds with
fifteen cells the immediate discharge (with 30 ohm shunt)
was 220 mm. Again charged for fifteen seconds and
insulated for sixty seconds, the discharge was 36 mm., and
upon this being repeated many times it became evident
that by reason of the low absolute insulation resistance of
the body the charge was given off to air in a short period
of time. As a result of this and another series of tests with
earth connections, I find that the body, when insulated,
does not act as a plate of a condenser as regards the earth,
but that the body itself acts in every respect as a condenser
of low insulation." But there is this to be said : the quan-
tity of the charge communicated to the plates depends directly
G
82 STUDIES IN ELECTRO-PHYSIOLOGY:
upon the electromotive force of the cells used.* In the tests
to which reference has been made the electromotive force
was 20 volts. The average electromotive force of man
may be put at a maximum of 5 millivolts, so that the
quantity of the charge with 20,000 millivolts would be
many times greater than with 5 millivolts, and this, I
think, suggests (1) that although the insulating processes
of the body are not adapted to withstand the strain of
high tension (and capacity is regarded as a strain upon the
dielectric), they are adequate for the purposes for which
they were designed ; (2) that the body can be inductively
influenced by any outside source of electrical energy of a
potential appreciably higher than 5 millivolts ; and (3)
that as the quantity of current exhibited by a healthy man
may be expressed as being less than 1 micro-ampere, we
are justified in assuming that the law of retardation applies
with equal force to the human organism.
In the elaboration of my theory of the nature of the
nerve impulse, i.e., that it is neuro- electrical and due to
the association of iron as the positive and oxygen as the
negative element, in the presence of an exciting liquid, I
was confronted by the fact that I could not, as an elec-
trician, recognise or point to any organ in the body which
could be said to be a generating station. I am indebted for
what may be the missing link to a communication from
Dr. E. W. Martin, from which I shall presently take the
liberty to quote. Before doing so, however, it may serve
a useful purpose as this work is intended for the guidance
of those who are not familiar with applied electricity to
offer a few observations upon so-called positive and negative
currents ; my authority being the text-book of Telegraphy,
by Preece and Sivewright.
u A current is always supposed to flow from the point
of higher potential to that of lower potential. The former
* See also p. 91 et seq.
ANIMAL AND VEGETABLE 83
point is taken to be positive to the latter ; and, vice versd,
the lower is taken to be negative to the higher point. The
terms positive and negative currents are frequently used,
but they are misnomers. There is only one current
flowing and it varies in direction. It is quite correct to
apply the term positive or negative to currents with respect
to a given point, and by those terms to imply direction only,
for while stationed at a given place currents may flow from
or towards us ; but what is a positive current at one point
is a negative current at another. ... A current can only
be constant when we have two points separated from each
other by an invariable resistance, and maintained at the
same difference of potential."
We shall see, later on, that in the human body neither
the resistance of any given circuit nor the same difference
of potential can be maintained owing, quite apart from
disease, to variations of external temperature and the
fluctuating nature of the human electromotive force ;
and the fact is emphasised that in the estimation of body
deflections we must have a fixed point of departure, and
that that point should be upon the central line.
We will now consider Dr. Martin's letter upon " The
Source of Body Energy and its Relation to the Nervous
System."
He says : " The theory of neuro- electricity, gal-
vanometric tests, and treatment, founded upon the theory
propounded by Mr. Baines, has proved of value in the
treatment of certain conditions of disease. The argument,
therefore, follows that the basis of the theory is sound.
In detail, however, the original conception of the brain
as a generator, and the nervous system as a carrier, of a
constant current came into collision with established
physiology, and endangered the hearing of a piece of
scientific work of great value.
" I advance a theory which may bean explanation, and
84 STUDIES IN 'ELECTRO-PHYSIOLOGY:
which, if proved to be correct, will range the physiologist
and the electrical expert on the same side, while adding a
fresh conception of the body as a whole in relation to one
source of life ; at the same time enabling us to more easily
understand galvanometric readings of the body energy and
to interpret them rightly.
" As a foundation of the theory, I propose to start from
one fact which, when analysed, may lead to a more correct
conception of our source of energy. . . .
" The question raised is one which, so far as I can see,
must be answered by those who would explain ' neuro-
electricity,' equally with those who deny its existence.
Argument
" The conditions before the birth of a child, and
immediately after birth, offer a field of thought. What is
it that enables the child to support an existence separate
from the mother ?
" Let us examine the problem, bearing in mind that
what we require from the electrical expert's point of view
is (1) a linking up of the body with a source of energy, and
(2) an organ that will act the part of generator.
" Before birth the foetus is alive, but nutrition, growth,
development, are carried out by the action of the maternal
blood-stream. Circulation through the fcetus is estab-
lished, with one important exception : there is no circulation
through the lung.
" Digestive organs, nervous system, etc., are present,
but are functionally in abeyance till the act of birth has
taken place. What, then, is the difference ? It is the
act of breathing which determines the separate existence of
the child from the mother.
" Before this act has taken place the lungs contain
neither blood nor air. Their function could not be called
into play until the need arose to link up the life with its
future source of energy.
ANIMAL AND VEGETABLE 85
" The act of birth, therefore, brings with it the power
to use a mechanism by means of which the oxygen of the
air can be used by the body. From that moment the whole
of the latent mechanism is in working activity and the
individual life is complete.
" Here we are at one with known facts. Let us now
examine the electrical problem in this light. We have seen
that we require (1) a source of energy, and (2) an organ to
act as generator ; i.e., an instrument or apparatus which,
when supplied with material, will generate force.
" We have found the source in oxygen, and the organ
in the body to use it ; let us see whether it is possible to
carry this analogy further.
" In the lung the state of things is air vesicle and
capillaries, the interchange between blood and air being
oxygen from the air to the blood to enter into combina-
tion with the haemoglobin (an iron- containing substance),
and CO 2 from the venous capillaries going outwards to
air.
" Now, any change between air and blood must take
place through the wall of the capillaries, and the physio-
logical fact of the permeability of membranes at once
arises. Professor Bayliss' Physiology, and I think, quoting
from memory, that the work on this subject has chiefly
been done by Professor Sherrington, states that the
absorption by colloid surfaces depends on the electrical
sign of the surfaces and the substance absorbed, and is
more an electrical than a chemical action. Also the experi-
ments on permeability of membranes depend on electrical
balance and the attraction and repulsion of electro-positive
and electro-negative ions, and is again a matter of electrical
rather than of chemical activity ; although it would,
perhaps, be better to say that chemical action follows the
electrical or ionic movement.
" Having found one possible source of energy,
86 STUDIES IN ELECTRO-PHYSIOLOGY:
generator, and the medium for the conveyance of energy, let
us next look at the distribution.
" The order of distribution seems to bear some signifi-
cance
" 1st. The heart muscle. Remembering the structure
of heart muscle, its ganglia, and the function
performed by the heart, the call for and supply of
this organ with energy is paramount.
" 2nd. Next in order of supply and importance is the
nervous system.
" 3rd. The other tissues and organs of the body.
" The order from the generator is, therefore, the pump
for circulating the carrier, then the nervous system, whose
chief function, through the sympathetic, is the regulation, by
vaso-motor and vaso-mhibitory nerve-fibres, of the blood
supply to all tissues and organs ; and if we substitute the
word ' energy * for ' blood ' we can follow the thought
through. This control is important in disease, as it gives
the power to send more blood to the area attacked, and the
converse is equally important as explaining a fallacy in
galvanometer testing, as I will show later.
" The voluntary system (apart from sensation) has
chiefly to do with the movement or the control of muscular
contraction resulting in movement. Striped muscle, i.e.,
the muscles under the control of the voluntary system,
will to the electrician at once suggest an electrical apparatus
which can be set in motion on being connected up.
" If, therefore, the nervous system, sharing the common
energy of the body with every other cell and organ, has a
special function of control to perform, it must have some
form of insulation or this energy would be dissipated
through moist tissue, and the control of blood supply and
the movement of muscle would be lost. It is probable,
indeed I think established, that the electrical balance of
each cell membrane throughout the body, and the resulting
life of the cell, are under the control of and kept in balance
ANIMAL AND VEGETABLE 87
by the sympathetic nervous system ; and that this is so is
again an argument in favour of an insulation, without
which stability could not be obtained.
" There may be fallacies which I am unable to detect,
but my belief is that in the normal state in quiescent nerves
there is an electrical equilibrium, that current passes only
on liberation of impulse from brain centres in the case
of the sympathetic from emotion at one end and from
irritant at the other and that, to control this discharge of
energy, insulation is imperative and will be demonstrated.
To experiment with a cut nerve opens the road to many
flaws which are obvious.
" From Mr. Baines' point of view it is necessary to prove
this insulation. That impulses pass along a nerve is
granted, but that this impulse is in the nature of an electrical
impulse has to be shown ; but to object because the word
' current ' is used instead of ' impulse ' seems an unneces-
sary obstacle to understanding, for the nature of a current
may be interrupted as well as continuous.
" The whole arrangement of the nervous system,
nodes, synapses, medulla, sheath, ganglia, etc., points to an
electrical system with many makes and breaks, shunts,
etc., and we have shown before that the fundamental
energising of the body is an electrical phenomenon.
" Returning to the blood-stream and for the moment
leaving out the specialised organs and glands, we come to
the question of connective, fibrous, and elastic tissues.
" Subcutaneous and other vascular connective tissues
may be regarded as the padding of the body. We have a
multitudinous cell-life, vascularity, and a controlling nerve
supply. Here, then, we have a storage of energy separate
from the closed circuit of the nervous system ; closed in
relation to the other tissues of the body. In this tissue, as
in the specialised organs, the interchange from blood to cell
goes on, but in this case we get some diffusion through
88 STUDIES IN ELECTRO-PHYSIOLOGY:
moist tissues and only partial insulation by the skin. This
no doubt gives us the average reading on the galvanometer
scale of ordinary normal deflections, except in the case of
the finger-tips and toes, which give constant readings and
are probably the earth (air) outlets of the nervous system.
" At the finger-tips, no matter how dry the skin may
be, we are always able to measure a current. Also reversal
of sign is obtained from hand to hand and from the thumb
to the fingers of the same hand.
" With other portions of the skin over the body a com-
paratively dry condition will lead to no current being
obtained, while moisture will produce a current equal in
E.M.F. at any part.
" In testing the body as apart from the hand-to-hand
measurement, Mr. Baines uses a larger electrode to a fixed
point and goes over the body with one of smaller diameter.
By this means the sign, which is unimportant, remains the
same, and it becomes easier to estimate the deflections due
to faulty condition. It has been claimed that these
currents are ' skin currents ' and that a metal electrode
of larger size, with moist skin, will set up a current, and
that the use of electrodes of similar size will lead to different
readings, change of sign, etc. I have elsewhere shown that
skin and metal to skin and metal through the galvanometer
does not always exhibit current, so we must look further
for an explanation.
4 ' If we note the different thicknesses of the skin, apart
from pressure areas, we find that where the greatest depth
of connective tissue is, or where there is greatest vascularity,
the skin is, as a rule, thicker ; and that even in specially
vascular areas, like the scalp, there is a special arrangement
of skin and connective tissue, we are able to trace in it some
purpose. If, then, we remember the fact that the develop-
ing foetus is open, and that later it is joined down the
centre line, and that fibrous tissue is a non-conductor, we
ANIMAL AND VEGETABLE 89
at once can see that by using electrodes of a similar size
we should frequently obtain change of sign, which is avoided
by adopting Bailies' method.
" Mr. Baines has pointed out that, in testing, a slow
excursion, say to 200 mm., is met with which may be
mistaken for a leakage from the nervous system. Anyone
using the galvanometer will soon learn to judge this
condition ; quantity as evidenced by the rapidity of
excursion being the test of a nerve flaw.
" If the theory advanced of the source and distribution
of energy is correct, this false reading can be explained.
A local vaso-motor disturbance would result in increased
blood supply. For this read conveyance of energy, and
at once you have a local increase of potential, and the skin
insulating for a normal potential only, will allow of the
larger escape and give an excursion, but without the
quantity of a leakage from the insulated nervous tracts
where the potential is probably higher.
" It will be understandable that the readings from this
cellular source of energy are comparatively unimportant,
and that the larger electrode may be used to govern the
direction of the flow without in any way interfering with
the usefulness of the readings.
" An escape through a flaw in the insulation of a nerve
would result in diffusion, through moist substance, of a
current of much greater quantity, and give the rapid deflec-
tion of larger extent which one has learned to associate
with a genuine alteration in tissue metabolism."
Unfortunately, as I have said in another chapter, our
knowledge of condenser action in the body is limited by the
absence of information regarding the specific inductive
capacities of natural dielectrics. With special reference to
the velocity of the nerve impulse the experiments of Dr.
Le Bon are of importance. He came to the conclusion
that electricity is able to propagate itself in insulators 43
90 STUDIES IN ELECTRO-PHYSIOLOGY:
well as in conductors, but much more slowly in the first
case than in the second, the velocity varying from a few
centimetres to 300,000 kilometres per second. In the
enormous margin between the two there is ample room for
speculation as to the causes which contribute to the
comparative sluggishness of the human nerve-current.
The same authority showed that the particles emitted
by an electrified point were identical with those which
came forth from radium ; suggesting, by inference, that
the force known as electricity may be made up of more
than one form of energy.
ANIMAL AND VEGETABLE 91
CHAPTER VI
INDUCTIVE CAPACITY
As a good deal depends upon a proper appreciation of
the function of a condenser, as that apparatus is used in
telegraphy, it may be well to make it clear ; taking as my
authorities Sir Wm. Preece, F.R.S., and Sir James Sive-
wright, joint authors of Telegraphy.
" When a quantity of electricity flows through a line
in the form of current, the first portion of the current is
retained or accumulated upon the surface of the wire, in
the same way that a charge is retained or accumulated upon
the surface of a Ley den jar. The quantity accumulated
depends (1) upon the length and diameter of the wire,
(2) upon its distance from the earth and earth-connected
bodies, (3) upon the insulating medium surrounding the
conductor.
" The effects of capacity are, first, that it absorbs all
the electricity of a short momentary current and prevents
the appearance of any current at the distant station, and,
second, that as it absorbs the first portion of every current
sent, it has the same effect as if it retarded or delayed the
first appearance of the current at the distant end. Thus
the apparent velocity of the current is diminished more or
less in proportion to the capacity of the circuit, velocity
being in the inverse ratio to the capacity.
" ' Condenser ' is a term applied to an apparatus
usually composed of alternate layers of tinfoil and paraffined
92 STUDIES IN ELECTRO-PHYSIOLOGY:
paper, so arranged as to form a flat Leyden jar of large
surface, and constructed to give any capacity that may be
required. It may be shown thus
Fig. 2.
a, a 1 , a 2 , fe, 6 1 , 6 2 are square pieces of tinfoil separated by
sheets of thin paper steeped in melted paraffin wax. The
series a, a 1 , a 2 are connected together, and so are the
series 6, b\ b 2 . A and B thus become connected with
what may be regarded as the inside and outside coatings of
a Leyden jar, and by putting one pole of a battery to A,
and the other pole to B, we can communicate a charge to
the plates the quantity of which will depend (1) directly
upon the electromotive force of the cells used, (2) directly
upon the total surface of each series of conducting plates
opposed to each other, (3) inversely as the distance between
each pair of plates, and (4) upon the nature of the in-
sulating material used to separate the conducting plates."
Condensers are conventionally represented by parallel
lines, i.e.
Fig. 3.
Now, the electrostatic capacity of a line is unequally
distributed, and its working conditions are naturally
affected by this distribution. A circuit may be made up
ANIMAL AND VEGETABLE
93
T
of overground wires, underground wires and cables ; and
one of the principal functions of a condenser, or of a series
of condensers, is in telegraphy to compensate for and
regulate this inequality of distribution. In the human
body, whose circuits are infinitely more com-
plex than the most complicated telegraph
system, they are not only designed for the
performance of this function, but for the
equally important one of changing the sign of Fig. 4.
current from efferent to afferent, or vice versa.
" A simple condenser is, as we have seen, shown in Fig. 4.
If we connect that to a galvanic cell (Fig. 5) the charge
communicated to plate A will (if the plates
are of the same area) induce a charge of
equal tension but of opposite sign upon
plate B.
V.J J "The capacity varies directly as the
surfaces of the opposing plates. If, now,
Flg " 5 * three condensers F 1? F 2 , F 3 , be joined up
as shown by Fig. 6, the effect is clearly to connect
all the A plates together, so that, practically, they become
nh
one plate of large area, and so also with the B plates ;
hence, by such an arrangement, the total capacity (F)
becomes
F = FX + F 2 + F 3
and the condensers are said to be connected in parallel.
" Again, the capacity varies inversely as the distance
between the plates. Assume the distances in the following
94 STUDIES IN ELECTRO-PHYSIOLOGY:
figure to be L, JL, 1. ; then, if the three condensers be
*1 *2 *3
joined as shown, the B plate of F! is practically brought
Fig. 7.
opposite that of F 2 , by the connection of the A plates of
Fj and F 2 , but at distance j=r -f ^ , and similarly with
F 2 and F 3 , so that the distance between plate B of F x
and plate A of F 3 is p -f _]_; and the capacity (F)
is therefore
F *
JL JL JL
TS 1 * T? ~T~ TJ*"
^1 *2 ^8
When condensers are connected in series their joint
capacity is the reciprocal of the sum of the reciprocals of
their respective capacities, while in parallel the joint
resistance is equal to the reciprocal of the sum of the
reciprocals of their respective resistances. In voluntary
muscular fibre the sarcomeres are, in my belief, joined up
in groups in series as well as in parallel, and it may serve
a useful purpose to append a practical illustration or two
from Submarine Cable Testing and Working, by my name-
sake, G. M. Baines, of the Eastern Telegraph Company.
ANIMAL AND VEGETABLE
95
Let C and D (Fig. 8) represent two condensers with
capacities of 15 and 5 microfarads respectively, and B
cells of an electromotive force of 3 volts ; the distance
between the plates of C being equal to a and between those
of D equal to b.
a
Fig. 9.
In the above figure the same pair of condensers show
under the conditions which actually regulate the test of
their joint capacity ; the inner plates of both having been
eliminated.
C and D are now, to all intents and purposes, a single
condenser with, it is important to observe, a distance
between its plates equal to a + b. Without calculation it
will be recognised that the joint capacity of the pair must
be smaller than the capacity of either of them if tested
alone, because of the increased distance between the
plates.
Upon closing the battery circuit the outer plates of C
and D are equally and oppositely charged to the potential
difference of the battery, viz., 3 volts. When this potential
difference has become established, the current from the
battery will cease to flow. The neutral condition of the
inner plates of C and D has, meanwhile, been disturbed by
96 STUDIES IN ELECTRO-PHYSIOLOGY:
the inductive effect of the battery charge, and quantities
of electricity equal to that charge, but of opposite sign to
each other, will be collected upon the inner plates ; these,
however, and therefore their electrical condition, do not
in any way influence the joint capacity of the two con-
densers, which in accordance with the law must be
1 1
= TO = 15 = 3-75 microfarads ;
the charge being 3-75 x 3 = 11-25 microcoulombs, and
the potential differences of the charges on C and D 0-75
volt and 2-25 volts respectively.
Similarly the charges on three condensers of varying
capacities, and connected in series, as also their potential
differences, may be shown by employing three glass vessels
for the purpose ; the larger the vessel the greater the
capacity.
6 c
a.
f?jr=
'r^^.
~-:-=^
L VV^^r3e=
fz
^r
S'
7
Fig. 10.
a is J and b f the size of c, and we will call the respective
capacities 2, 4, and 6 microfarads and the E.M.F. of the
battery 2 volts.
The joint capacity of a, b, and c will be
mcros.
The charges on the three condensers will be exactly the
ANIMAL AND VEGETABLE 97
same in amount, but their potential differences will vary in
proportion to the plate areas/,/!, and/ 2 .
In a the charge has only a surface of 2 microfarads over
which to diffuse itself ; consequently, as this surface is the
smallest of the three, the potential difference of its plates
will be the maximum. In b it will be only half as great as
in a, while in c it can only be equal to or -.
2 3
The sum of the potential differences should equal the
E.M.F. of the battery, and would work out as follows :
a = 1-091 volts (about)
b = 0-545 volt
c = 0-364
Total 2-000 volts
It will thus be seen that to raise a to the same potential
difference as c, only one-third of the charge it has accepted
in series would be required. Similarly the joint capacity
of any number of condensers of equal capacity connected
in series is the capacity of any one of them divided by their
number.
It will also be seen why, if the sarcomeres of voluntary
muscular tissue are joined up in series, it can only be in
limited groups of them, otherwise capacity and potential
difference would approach the vanishing point before the
initial impulse had travelled very far. That connection is
made in this manner, i.e., in series -par all el, will be apparent
when study is made of the terminations of nerves in
muscle (p. 150).
We have now learned some very important facts, viz.
(1) That capacity varies directly as the surfaces of
the opposing plates, (2) that the velocity of the current is
in the inverse ratio to the capacity, and (3) that capacity
varies inversely as the distance between the plates. That
being so, it follows : (1 ) the larger the plate-area the greater
H
98 STUDIES IN ELECTRO-PHYSIOLOGY:
the capacity, (2) the greater the capacity the lower the
velocity of the current, and (3) the closer the conducting
plates are together the greater the capacity.
In the human body none of the conducting plates,
discs, or points are of large area, but while no considerable
variation of capacity is possible by this means, Nature can,
and apparently does, overcome the difficulty by approach-
ing the conductors closely to each other, as in striated
muscular fibre, and by connecting them sometimes in
parallel (as in Fig. 6). In other parts of the body structure
in various arborisations, for instance there must be
differences of capacity and resistance, and therefore
velocity of current or nerve-impulse cannot be uniform
throughout the whole of the nervous system.
This is an opinion arrived at after experiment and
careful thought, and I am encouraged to find myself
supported in the view by several authorities. Halliburton
says : " The rate of stimulation makes no difference ;
however slow or fast the stimuli occur, the nerve-cells of
the central nervous system give out impulses at their
normal rate.
" The same is seen in a reflex action. If a tracing is
taken from the gastrocnemius of a pithed frog, the muscle
being left in connection with the rest of the body, its
tendon only being severed and tied to a lever, and if the
sciatic nerve of the other leg is cut through, and the end
attached to the spinal cord is stimulated, an impulse passes
up to the cells of the cord, and is then reflected down to
the gastrocnemius under observation. The impulse has
thus to traverse nerve-cells ; the rate of stimulation then
makes no difference ; the reflex contraction occurs at the
same rate, 10 or 12 per second . . . recent experiments by
Piper ... he found that each wave of the curve obtained
by the graphic method is really itself due to fusion of
contractions occurring at a more rapid rate. The method
ANIMAL AND VEGETABLE 99
he employed was to count the number of electrical varia-
tions which accompany a voluntary contraction, on the
assumption that each fundamental unit of the contraction
has an electrical change as its concomitant. . . . The
number of electrical variations is found to be a fixed one
for each muscle, but to vary in different muscles. Various
spinal and cranial motor centres have thus different
rhythms, and of those hitherto studied the cells of the
motor fibres of the fifth cranial nerve have the highest
rate of discharge, 86 to 100 per second. In muscles
supplied by spinal nerves the rate is lower, 40 to 60."
Many other proofs could no doubt be cited, but we
have an example of, as I think, variation of capacity in
Purkinje's fibres in the auriculo-venticular-bundle of cardiac
muscle. These are large, quadrangular cells with granular
protoplasm, and striated, it is said, only on the margins.
The slow rate of propagation of the wave suggests greater
capacity than in ordinary striated muscle, and therefore
either (1) the plates are closer together, (2) they are larger,
or, (3), what is more probable and indeed indicated by
physiological diagrams, they are connected in parallel. If
this is so the argument should apply with even greater
force to plain muscle, but, unfortunately, the structure of
the latter is not sufficiently defined to enable a definite
opinion to be given.
In cardiac muscle the movement is rhythmical, and it
differs from that of voluntary and plain muscle in that,
subject to regular periods of rest, it is onstant, whereas
in the others it is intermittent. We can readily under-
stand this when we remember that discharge or neutralisa-
tion does not take place instantaneously unless there is
actual contact. Regular periods of time or rest would be
necessary in any such circuit if it was required to work
continuously and automatically. The retardative action
is equally pronounced in the discharge as in the charge, and
100 STUDIES IN ELECTRO-PHYSIOLOGY:
both velocity of impulse and periodicity are dependent
upon the two factors of resistance and capacity.
It is a pity that we have no data as to the specific
inductive capacities of the natural dielectrics of the body,
such as cholesterol, neuro-keratin, lecithin, kephalin, the
medullary sheath, etc., as a basis for calculation. As
against the 1 of air, sulphur is 1-93, but as other dielectric
substances range between 1-77 and 10-1, it is evident that
further research is called for to determine this important
point.
Apart from, but in addition to, specific inductive
capacities, I should much like to have the following
information :
In a selected piece of striated muscle
(1) The surface area of the clear spaces,
(2) The thickness of Krause's membrane,
(3) The average number of sarcomeres connected by
the end-plates of motor-nerve fibres, and
(4) Whether such end-plates do or do not connect the
clear spaces thus
Fig. 11.
That would be something to go on with.
I learn from The Human Species, by Ludwig Hopf,
that an average size piece of striated muscular fibre measures
20-4 mm. in length by 0-06 mm. diameter. If we had the
thickness and specific inductive capacity of Krause's
membranes we could, at least approximately, calculate the
capacity of each sarcomere.
ANIMAL AND VEGETABLE 101
In plain muscle the figures given are 0-045 to 0-225 mm.
long by 0-004 to 0-007 mm. wide. These are given by
Hopf. Halliburton states that the fibres of voluntary
muscle average about 1 in. in length and ^fe (0-05 mm.)
in diameter.
To TEST THE BODY FOR CAPACITY.
There are several ways of doing this, but as extreme
accuracy is not required, the most convenient method is by
direct discharge. For this a " universal " shunt and a
standard condenser of J to 1 micro are required, and the
subject should stand upon an ebonite slab to obtain good
insulation.
Using fairly high power (say 20 volts) at first, and
afterwards not more than 0-5 volt, take two sets of observa-
tions in the following manner. Charge the standard
condenser Fj by the battery for a given number of seconds
and discharge it through a shunted galvanometer. Note
the immediate deflection and call it d lf Next, charge the
condenser to be measured (the body), F 2 , by the same
battery ; discharge it through the galvanometer and again
note the immediate deflection, d 2 . Then
F i; F 2 ::^:rf 2 , or F 2 = F^ 2
i
FI
If -j- is made a submultiple of 10, d 2 gives the capacity at
once.
The multiplying power of the shunt or shunts used is
found by the formula
G + s
G being the resistance of the galvanometer in ohms,
s the resistance of the shunt,
102 STUDIES IN ELECTRO-PHYSIOLOGY:
The actual connections in my original tests were :
G
Body
/5 cells
3 L+i <
!>+.
: -Discharge Key
-
Insulated
Fig. 12.
dj was taken with a standard condenser of 1 microfarad
capacity, a galvanometer resistance of 7,000, and a shunt
of 80 ohms. The immediate discharge, or d l9 was 204 mm.,
or, multiplied by - - = 18,033-6 mm. ; while <Z 2 , with
s
a 80-ohm shunt, was 290 mm., or 67,947 mm. in full. This
by the formula F 2 = F j gave 376 micros (nearly) as
the capacity of the body. In taking this test it is advisable
that the observer stands as far from the subject as
possible.
ANIMAL AND VEGETABLE 103
CHAPTER VII
CELL REPRODUCTION
MITOTIC DIVISION. THE CENTROSOME AND THE
ATTRACTION SPHERE
IN a diagram of a cell (Schafer) the centrosome is
shown double and lying near the nucleus.
This is a minute particle (centriole), surrounded
by a clear area (attraction sphere) and from it
radiate into the surrounding protoplasm a
number of fine fibrils and dot-like enlarge-
ments at intervals. The twin spheres are
connected by a spindle-shaped system of delicate fibrils
(achromatic spindle), and this duplication invariably precedes
the division of a cell into two.
In the process of division of a cell many changes occur,
but it is always " preceded by the division of its attraction
sphere, and this again appears to determine the division of
the nucleus." These changes are, briefly, as follows :
" (1) The network of chromoplasm-filaments of the
resting nucleus becomes transformed into a sort
of skein, formed apparently of one long convoluted
filament, but in reality consisting of a number of
filaments (spirem) ; the nucleus membrane and
the nucleoli disappear, or are merged in the skein.
" (2) The filament breaks into a number of separate
portions, often V-shaped, the chromosomes. . . .
As soon as the chromosomes become distinct they
are often arranged radially round the equator of
the nucleus like an aster.
104 STUDIES IN ELECTRO-PHYSIOLOGY:
" (3) Each of the chromosomes splits longitudinally
into two.
" (4) The fibres separate into two groups, the ends being
for a time interlocked,*' i.e., complete division
has not taken place.
" (5) The two groups pass to the opposite poles of the
now elongated nucleus and form a star-shaped
figure at either pole (diaster). Each of the stars
represents a daughter nucleus." At this point
complete separation has occurred, and the following
appearance is presented (Fig. 13) :
Fig. 13. Fig. 14.
" (6), (7), (8). Each star of the diaster goes through the
same changes as the original nucleus, but in the
reverse order, viz., a skein, more open and rosette-
like, then a closer skein, then a network ; passing
finally into the typical reticular condition of a
resting nucleus." The penultimate stage is shown
in Fig. 14 and is the stage immediately preceding
the division of the cell.
" The protoplasm of the cell divides soon after the
formation of the diaster. During division fine lines are
seen in the protoplasm, radiating from the centrosomes at
the poles of the nucleus, whilst other lines form a spindle-
shaped system of achromatic fibres within the nucleus,
diverging from the poles towards the equator. These are
usually less easily seen than the chromatic fibres or chromo-
somes, but are not less important, for they are derived from
the attraction-spheres. These with their centrosomes
alway initiate the division of the cell ; indeed, they are
ANIMAL AND VEGETABLE 105
often found divided in the apparently resting nucleus, the
two particles being united by a small system of fibres forming
a minute spindle at one side of
the nucleus. When mitosis is
about to take place this spindle
enlarges, and as the changes in
the chromatin of the nucleus \
occur which changes involve
the disappearance of the nuclear rf ~15~~
membrane the spindle gradually
passes into the middle of the mitotic nucleus, and with
the fibres of the spindle therefore completely traversing
the nucleus. (Fig. 15.)
" The spindle-fibres appear to form directing lines, along
which the chromosomes pass, after the cleavage, towards the
nuclear poles to form the daughter nuclei." *
In most animal cells the protoplasm becomes constricted
into two parts midway between the two daughter nuclei*
" Each daughter cell so formed retains one of the two
attraction-particles of the spindle as its centrosome, and
when the daughter cells are in their turn again about to
divide, this centrosome divides first and forms a new spindle,
and the whole process goes on as before." (Schafer.)
To go back a little, to the properties of living matter,
we learn that " living cells exhibit irritability or the pro-
perty of responding to stimuli," electrical or otherwise,
much in the same way that nerve and muscle exhibit it
and I think we can postulate it as almost, if not quite,
unanswerable that to respond to electrical stimulus the
structure itself must be to some extent electrical. That
it exhibits irritability under mechanical, chemical, or
thermal stimuli does not affect the question, because a
stimulus of any kind must disturb the equilibrium of an
electrical unit of so delicate and sensitive a nature.
* The italics are my own.
106 STUDIES IN ELECTRO-PHYSIOLOGY:
It now remains to be seen whether I am in any way
justified in applying the term " electrical unit " to any
animal cell.
Supposing the single centrosome to be an electrified
body, no electrical action of attraction or repulsion could
take place within it while it remained single,
but before any cell -reproduction can begin
it is duplicated, and duplicated in a very
peculiar form, the fibrils having dot-like
enlargements at intervals.
In the diagram the dark spots represent
the centrioles, and if, as I imagine, they
are bodies similarly electrified, the immedi-
ate result would be the exercise of repulsion
between the two, and consequent elongation of the cell.
Dividing the centrioles is a clear space over which
repulsion would first be exercised.
In Schafer two diagrams are given to illustrate the
changes which occur in the centrosomes and nucleus of a
cell during the process of mitotic division :
Fig. 17.
Up to the point shown in A, repulsion seems to continue,
and we are told that " the spindle-fibres appear to form
directing lines, along which the chromosomes pass, after
the cleavage, towards the nuclear poles to form the daughter
nuclei." It would seem, however, that the repulsive force
had reached its limit and that no further elongation of the
cell was necessary, because at an intermediate stage
ANIMAL AND VEGETABLE 107
between A and B, while the force was still being exerted,
the process of contracting the exoplasm in the middle in
order to ensure the division of the cell at that point must
have gone on ; and in B we see that the lines of force, or
the spindle-fibres, are ceasing to exist. That being so, and
the cell having divided into two parts, each with its nucleus,
nucleolus, and single centrosome, it prepares itself for
renewed growth and for re- division.
I am, of course, aware that the chemical changes which
take place are all important, but they are not in my depart-
ment, nor am I qualified to deal with them. I am en-
deavouring, and shall continue to endeavour, to point out
that the structure of the body is primarily electrical, and
that electrical, or neuro-electrical, action is precedent to
chemical change.
And when we know more about their precise con-
nections I am sure we shall find that the nucleus and
nucleolus play a very important part in the neuro-electrical
scheme of cell-reproduction. In this regard I should like
to draw the attention of my readers to that section of this
work which treats of ganglion cells in their electrical
aspect, and would further observe that in the absence of
stimulus or excitement the amceba assumes, and with it,
I take it, all cells assume, a form more or less spherical or
ovoid, " elongated, annular, or irregularly lobulated "
(Halliburton), which in a condition of rest, or, in other
words, prior to change, is their natural shape.
It will be seen also that after the division of the cell has
taken place the single centrosome
(see Fig. 18) occupies a position close
to the nucleus. In that state it is at
rest, in the sense that the nucleus
is at rest. When, however, the time
has arrived for division of the cell to
commence the centrosome is seen as in F| S- 18 -
Fig. 19,
108 STUDIES IN ELECTRO-PHYSIOLOGY:
At first sight one might be inclined to think that its
position is not in favour of the hypothesis I have advanced,
because if the diagram correctly represents its position,
as I cannot doubt it does the repulsive force would be
exerted longitudinally, and in such case would merely
elongate that portion of the cell to the right of the nucleus.
That would be so if, immediately the
repulsive force begins to operate, the
nucleus underwent no change. But
it does change. The network of
chromoplasm filaments of the resting
nucleus becomes transformed into a
sort of skein, into which the nuclear
membrane and the nucleoli disappear.
The whole cell, with the exception of its exoplasm,
appears, in fact, to be broken up, and its component
parts to be marshalled into order by the centrosomes-
But in what manner ? If the broken-
up nucleus was between the attraction ,--" ""*%,
spheres, as shown by Schafer(Fig. 20), it /
is quite evident that a repulsive force
alone would, so long as it continued to be
exerted and for so long as the disinteg- \
rated nucleus had no polarity, maintain
the substance between the attraction
spheres at the same distance from each of them. It
follows, logically, therefore, that if in the process of
division one part of the cell cleaves to one attraction
sphere, and the other part of the cell to the other attrac-
tion sphere, there must be a difference of polarity between
them.
Suppose, for instance, the attraction spheres to be
similarly electrified and to repel each other, so that they
become farther apart, with a certain, non- electrified (or
similarly electrified at lower tension) substance between
ANIMAL AND VEGETABLE 109
them. Neither the nucleus nor the nucleolus is non-
electrified of that I am sure but during the early process
of division the nuclear membrane and the nucleoli disappear
or are merged in the skein, and, inferentially, lose polarity
for the time being by loss of insulation and consequent
diffusion. The moment, however, that insulation is even
partially restored polarity would come into play ; and
reference to physiological diagrams makes it clear that at
this stage of division the two attraction spheres and the
two parts of the nucleus are in close proximity, each with
the other.
Assume that the attraction spheres and the nucleus
are oppositely electrified, and we can understand why, in
the first place, the single centrosome lies as near the
nucleus as the structure of the cell permits ; secondly,
there being an intervening space between the centrosomes,
they should separate at that part, and in the process of the
nucleus breaking down repel each other until they form
poles at opposite ends of the cell. At that stage the
nucleus would be in a condition of temporary disintegration
or disarrangement, but as its insulation returned it would
regain polarity, and, the pull being exactly equal, we can
conceive one- half of it trending, by attraction, to the left
and one- half to the right centrosome. Equilibrium would
then be restored, and as the exoplasm completed the circle
around each of the daughter nuclei, or rather around the
protoplasm surrounding each daughter nucleus, the cell
should divide by constriction.
I will endeavour to put it briefly. In its condition of
rest, or, as I prefer to say, of development, I assume the
centrosome and nucleus to be of opposite polarity. Upon
duplication, the two centrosomes move to extreme ends
of the cell. The moment the nucleus loses its membrane,
and with it its insulation, it becomes similarly electrified,
the chromosomes exercise a repulsive influence upon each
110 STUDIES IN ELECTRO-PHYSIOLOGY:
other under the control by the lines of force from the
centrosomes, and, being in multiples of two, must divide
in equal numbers at the equator. So soon, however, as the
two sets of chromosomes regain insulation they again
become oppositely electrified, are attracted by the centro-
somes, and form two equal groups.
SEGMENTATION OF THE OVUM.
Usually, it is said, the two daughter cells are of the
same size, but this is not so in the case of the ovum, which,
before fertilisation, divides twice (by hetero- and homo-
typical mitosis respectively) " into two very unequal
parts, the larger of which retains the designation of ovum,
while the two small parts which become detached from it
are known as the polar bodies. Further, in the formation
of the second polar body a reduction-division occurs, and
the nucleus of the ovum, after the polar bodies are ex-
tended, contains only one-half the number of chromosomes
that it had previously e.g., twelve in place of the normal
twenty-four in man, and two instead of four in Ascaris
Megalocephala ( var. bivalvens). Should fertilisation super-
vene, the chromosomes which are lacking are supplied by
the male element (sperm-cell), the nucleus of which has
also undergone, in the final cell-division by which it was
produced, the process of reduction in the number of
chromosomes to one-half the normal number. The two
reduced nuclei which are formed respectively from the
remainder of the nucleus of the ovum after extrusion of the
polar bodies, and from the head of the spermatozoon,
which contains the nucleus of the sperm-cell are known
(within the ovum) as the sperm and germ nuclei, or the
male and female pronuclei. When these blend, the ovum
again contains a nucleus with the number of chromosomes
normal to the species." (Schafer.)
It will thus be seen that while the process of division
ANIMAL AND VEGETABLE
111
of the ovum is more complicated than that, for instance,
of various kinds of somatic cells, it obeys the same law of
alternate repulsion and attraction.
This may be more readily comprehended by study of
the fertilisation and first division of the ovum of the worm
Ascaris Megalocephala, owing to the comparative simplicity
of the structure and the smaller number of chromosomes.
To put it, if I can, a little less technically than Schafer,
the ovum first discharges or extrudes from its interior two
portions of its nucleus, which form globules upon the ovum
and are called the polar bodies. These appear to play the
same part as the centrosomes and attraction spheres in
ordinary mitosis, and, disregarding for the moment the
fusion of the male and female pronuclei, the penultimate
stages of segmentation of the ovum, as shown by Schafer,
differ in no important respect from those of mitotic divi-
sion. Those stages are illustrated in the following
manner :
A. Fig. 21.
Ascaris Megalocephala.
A. Mingling and splitting of
the four chromosomes (c) ; the ach-
romatic spindle is fully developed,
but division of the cytoplasm has
not yet commenced.
B. Fig. 22.
B. Separation (towards the
poles of the spindle) of the halves
of the split chromosomes, and com-
mencing division of the cytoplasm.
Each of the daughter cells now has
four chromosomes ; two of these
have been derived from the ovum
nucleus, two from the spermatozoon
nucleus.
The extrusion of the polar bodies may be readily under-
stood. We know that (1) like electricities repel one
another, (2) unlike electricities attract one another, and
112 STUDIES IN ELECTRO-PHYSIOLOGY:
(3) the force of attraction or repulsion varies inversely as
the square of the distance between the two electrified
bodies, and directly as the amount of the charge of the two
bodies.
We are also aware that one of the earliest changes to
occur in mitosis and in segmentation is the breaking up of
the nuclear membrane. Assume, then, that the nucleus is
an electrified body and that those portions of it which
become the polar bodies are the first to detach themselves
or be detached from it, and the process of extrusion (by
repulsion) becomes clear. We are also entitled to believe
that their amount of charge is exactly equal, and have
seen that the chromosomes are always in multiples of two.
That being so, the latter should, upon regaining some
measure of their insulation, trend towards the polar bodies
(by attraction) in two groups of equal numbers.
In plant life sexual reproduction is first found in the
form of conjugation, as in mucor and spirogyra, where the
male and female elements are similar in shape and size. They
are simple cells, and fuse together to produce a zygospore.
" Fucus exhibits sexual production alone, and that in a
very typical manner. Male and female organs, in this case
trichomes, are present, which produce respectively small
motile male cells, spermatozoids, and passive, relatively
large female cells, the oospheres. One male cell fuses with
each female cell, which is now fertilised, and can develop
into a new plant. ' ' (Davis. )
The phenomena presented by sexual or asexual repro-
duction appear to be common to all forms of animal and
vegetable life, from the lowest to the highest. The presence
of nuclei has been demonstrated in the vegetative and
reproductive parts of fungi belonging to widely separated
orders, and Schizomycetes are of the class of fungi and
require organic matter as food ; in diatomaceae and in
protozoa ; and I have little doubt that if a sufficiently high
ANIMAL AND VEGETABLE 113
power could be used bacteria would be seen to be mostly
multicellular organisms which, by division and sub-
division, proliferate themselves in much the same way as
some of the species of confervoidese.
" In all probability," remarks Massee, in The Evolution
of Plant Life, " nuclei in a primitive state of differentiation
are present in all plant cells. The exact function of the
nucleus is not known, but judging from its almost universal
occurrence, and its behaviour in connection with the
formation of new cells, it must be supposed to perform
some important function."
With that view we must all be in agreement. Without
the nucleus cell-reproduction could not occur.
If that is so, however, and we suppose bacteria to
multiply themselves by the exercise of some electro-
chemical function, we must draw a line of demarcation
between aerobic and anaerobic micro-organisms. The
former need only contain some substance electro-positive
to oxygen for electrical action to occur, whereas the
latter should be self-contained ; that is to say, they should
be provided with both positive and negative materials,
requiring only suitable liquid to excite them.
Those who doubt the existence of a network in proto-
plasm would do well to examine, for example, the naked
protoplasm of a myxogaster (a yellow-coloured saprophyte,
generally met with on decaying wood), and the structure of
a grain of wheat and of rice, with special regard to the
arrangement and insulation of the starch cells. The same
phenomenon, in a modified form, will be observed ; and
if vegetable and animal physiology were always studied
together many other doubts and perplexities might be
resolved.
I am not concerned with enzyme action in its chemical
aspect, but certain facts in connection with it are not
without significance. The action is intracellular ; a rise
I
114 STUDIES IN ELECTRO-PHYSIOLOGY:
of temperature has much the same effect upon enzymes
as it has upon the velocity of the nerve impulse, they die
at much the same temperature as protoplasm, and their
activity is checked or destroyed by many of the chemical
substances, such as strong acids and alkalis which check
or destroy amoebic movement. This proves nothing, but
it opens the door to the suggestion that enzyme action,
instead of being wholly chemical, may be in some measure
electrical.
The best description of cell-division in plants is given
by Professor Vines in his Text-book of Botany. He says :
" The indirect division of the nucleus presents a series of
remarkable phenomena which are collectively designated
by the term karyokinesis. Beginning with the nucleus in
the resting-state, the first fact indicating the imminence of
nuclear division is that the two centrospheres " (centro-
somes) " separate and take up positions on opposite
sides of the nucleus, thus indicating the plane in which the
nuclear division is to take place, viz., at right angles to a
straight line joining the centrospheres : the change of
position of the centrospheres is doubtless effected by the
kinoplasm in which they lie. Changes are now perceptible
in the nucleus itself. The fibrillar network contracts and
becomes more dense, and breaks into distinct fibrils (chromo-
somes) consisting now of broad discs of chromatin with
narrower intervening discs of linin ; the tangle of the
somewhat V-shaped fibrils becomes looser as they separate
and move towards the surface of the nucleus. At this stage
the so-called nuclear membrane loses its definiteness, the
kinoplasm entering the nucleus without, however, dis-
placing the proper ground-substance of the nucleus. The
kinoplasm forms a number of threads, extending from one
centrosphere to the other, constituting the kinoplasmic
spindle " (achromatic spindle), " of which the centrospheres
are the two poles. Along these threads the fibrils move
ANIMAL AND VEGETABLE 115
till they reach the equatorial plane of the spindle, where
they constitute the nuclear disc, and are so placed that
their free ends point to either one pole or the other. Whilst
these changes have been going on, the nucleoli have dis-
appeared, being diffused in the nuclear ground-substance.
The fibrils now undergo longitudinal splitting into two,
and then the nuclear disc separates into two halves, in such
a way that one of each pair of fibrils produced by the
splitting of each primary fibril goes to each half. The
fibrils constituting each half of the nuclear disc now move
towards the corresponding pole along the spindle-threads,
changing their position as they go, so that when they
reach the pole their free ends point towards the equatorial
plane. On reaching the pole, each group of fibrils con-
stitutes a new nucleus ; it becomes invested by a mem-
brane, nucleoli reappear, and the fibrils resume the form
and structure of the resting nucleus. The two nuclei are
now completely formed, and are still connected by kino-
plasmic spindle-threads " (as in Fig. 17). " If no cell-
division is immediately to take place, no further change
occurs beyond the disappearance of the threads," and this,
it will be noted, is the stage immediately preceding division
in ordinary mitosis.
It is interesting to compare this account of vegetable
cell -reproduction with that given by Schafer of mitotic
division of the animal cell. The wording is different, but
the processes appear to be identical.
116 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER VIII
ANIMAL MAGNETISM
FOR more than a century we have heard of " Animal
Magnetism," and even some modern scientific men
Professor Rosenthal amongst the number are inclined to
attribute certain vital phenomena to magnetic influences
contained in the body.
The temptation to do so is great because some points
of resemblance may be found, but the view is a fallacious
one, as I will endeavour to show.
Inasmuch as we do not know what the force called
magnetism is, I do not propose to discuss it further than is
necessary. In the course of nearly forty years of research
work I have not been able to find any evidence of its
existence in the human body. Superficially, however,
Fig. 23.
certain phenomena may appear to be due to magnetic
control.
As instances of this we may take mitotic division and
ANIMAL AND VEGETABLE
117
the segmentation of the ovum, which, as we have seen,
permit of another and more reasonable explanation.
In a work called The Evolution of Seas, by Geddes and
Thomson, the illustration on preceding page is given of cell-
division, suggesting the internal disruptions and rearrange-
ments of the nucleus and protoplasm.
Let us compare that with the lines of force of a bar
magnet.
Fig. 24.
There is a quite remarkable similarity. We will,
however, instead of one, take two bar magnets and arrange
them thus and with this result :
Fig. 25.
They would repel each other ; the space between the
two might be called the achromatic spindle and the
magnets themselves the centrosomes. But we should have
precisely the same result if for the magnets we substituted
two similarly electrified bodies.
All the body phenomena can be readily and, I believe,
correctly explained in the same way, by the law of electrical
attraction and repulsion, both as regards intra- and extra-
cellular control, and to the best of my knowledge there is
no such thing as animal magnetism.
118 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER IX
SOME EVIDENCES OF THE LAW
ANIMAL VEGETABLE
Fig. 26.
One of the phases of the nuclear
chromatin filaments in the process
of ordinary mitosis of the somatic
cell. (Schdfer.)
Fig. 27.
One of the changes of the cell-
nucleus during division (AHium
odorum). (After Sachs.)
Fig. 28.
Epithelium-cells of salamandra
larva in different phases of division
by mitosis. (Schdfer.)
Fig. 29.
Changes in the cell-nucleus during
the division of the mother-cell of a
stoma of Iris pumila. (After Stras-
burger.)
ANIMAL AND VEGETABLE
119
ANIMAL
VEGETABLE
ex
Fig. 30. Fig. 31.
Diagram of a cell. p, proto- Young pollen-grain of Lilium
plasm ; n, nucleus ; n 1 , nucleolus ; Martagon, showing, c, double con-
c, double centrosome ; ex, exo- trosphere ; n, resting nucleus ;
plasm. (After Schafer.) n\ nucleolus ; p 9 protoplasm.
(After Guignard.)
Fig. 32.
Diagram showing a change in
the centrosomes and nucleus of a
cell in the process of mitotic divi-
sion. The nucleus is supposed to
have four chromosomes. (After
Schafer.)
Fig. 34.
Fertilisation of the ovum by the
spermatozoon (of a mammal).
(After Haeckel).
Fig. 33.
Germinating pollen-grain of Li-
lium Martagon with dividing nu-
cleus : the kinoplasmic spindle is
formed with a centrosphere at each
pole ; n is the nuclear disc formed
by the chromosomes. (After
Guignard.)
Fig. 35.
Oosphere, with spermatozoids.
(After Strasburger.)
120 STUDIES IN ELECTRO-PHYSIOLOGY:
The foregoing may be considered as direct evidences of
the universality of the law which governs all living things.
The examples I am about to cite cannot be said to fall,
without question, into this category, because while the
structures exhibit a striking resemblance, the organs are
not in all cases designed for the same purpose or function.
A little reflection, however, will show that, so far as structure
is concerned, it differs only in detail, in more or less perfec-
tion of finish or development ; the underlying principle is
there. Let us call them coincidences for the time being,
and trust to future investigation to link them in some
measure more closely together. It may here be said that
only from the " living " can any reversal of sign, implying
an electrical system, be obtained. In the " non-living '*
there is no difference of potential unless introduced by
some exterior vehicle of energy.
ANIMAL
VEGETABLE
Fig. 36.
Ganglion cell with nerve process
(human).
Fig. 37.
Original spore of Vaucheria Se$-
silis. (After Sachs.)
Fig. 38.
Section of spinal cord (human).
(After Schdfer.)
Fig. 39.
Diagrammatic sketch of trans-
verse section through portion of
root of Phaseolus multiflorus. (After
Sachs.)
ANIMAL AND VEGETABLE
ANIMAL VEGETABLE
121
Fig. 40.
Unipolar cell from spinal gan-
glion of rabbit. (After Schiifer.)
Fig. 41.
Usnea barbata. Transverse sec-
tion of a branch : r, epidermal
layer ; m, fundamental tissue ; c,
axial strand. (After Sachs.)
1
I
Fig. 42.
A. Spiral and reticular fibrils
in the sheath of a nerve-fibre.
B. Reticular appearance in the
medullary sheath of a nerve-fibre.
(Schdfer.)
Fig. 43.
A. Cells from a leaf of Hoya
Carnosa.
A. External view of the side
where the annular striae cross.
B. Portion of an annular vessel
from the fibro-vascular bundle of
Zea Mays. (After Sachs.)
The main differences between the two sets of figures
appear to be due to the absence of blood-vessels in the
vegetable sections ; although there seems to be a pro-
vision for the circulation of sap in the latter.
122 STUDIES IN ELECTRO-PHYSIOLOGY:
ANIMAL VEGETABLE
Fig. 44.
Formation of blastoderm in rab-
bit by division of ovum into a
number of cells.
A. During formation of
berry mass." (Schafer.)
mul-
Athcea rosea ; division of the
pollen mother-cells.
B. A stage thereof . (After Sachs.)
Fig. 46.
A group of cartilage-cells showing
the capsular outlines in the matrix
surrounding the group. (Ranvicr.)
Fig. 47.
The same, in a slightly different
form, as the above.
Fig. 48.
Part of a transverse section
the sciatic nerve of a cat.
of
Fig. 49.
A parenchyma cell from the
tyledon of Phaseolus multiflorus.
CO
(After Sachs.)
ANIMAL AND VEGETABLE 123
ANIMAL VEGETABLE
Fig. 50.
Two white fibre-cartilage cells
from an intervertebral disk (hu-
man). (Schdfer.)
Fig. 51.
Two thickened cells from the
cortical tissue of the stem of Lyco-
podium chamcecyparissus. (Sachs.)
Fig. 52.
From a section through a salivary
gland (human). (After Noble
Smith.)
Fig. 53.
Glandular colleter from a stipule
of Viola tricolor. (After Stras-
burger.)
Fig. 54.
Muscular fibre-cell from the small
intestine (human). (After Schdfer.)
Fig. 55.
A sclerenchymatous fibre (vege-
table). (After Strasburger.)
124 STUDIES IN ELECTRO-PHYSIOLOGY:
ANIMAL
VEGETABLE
Fig. 56.
Diagrammatic frontal section of
the pregnant human womb. (After
Haeckel.)
Fig. 57.
Ovule of a gymnosperm in
longitudinal section. (After
Sachs.)
Fig. 58.
Epithelium-cells of Descemet's
membrane. (After Smirnow and
(Sch&fer.)
Fig. 59.
Portion of the peripheral proto-
plasm of the embryo-sac of Reseda
odorata. (After Strasburger.)
ANIMAL AND VEGETABLE
125
ANIMAL
VEGETABLE
Fig. 60.
Endothelium of a serous mem-
brane (human). (After Schafer.)
Fig. 61.
Cells from a tendril of Cucwbita
pepo. (After Strasburger.)
Fig. 62. Fig. 63.
Section across a nerve bundle in Transverse section through a
the second thoracic anterior root young internode of the shoot axis
oi the dog. (After Gaskell.)
of Tradescantia albiflora. (After
De Bary.)
126 STUDIES IN ELECTRO-PHYSIOLOGY:
ANIMAL VEGETABLE
Fig. 64. Fig. 65.
Network of capillary vessels of Laticiferous vessels from a see-
the air-cells of the horse's lung, tion through the root of Scorzonera
(After Frcy.) hispanica. (After Sachs.)
LATICIFEROUS VESSELS.
The resemblance of laticiferous to blood-vessels is
remarked by Sachs. He says : " The laticiferous vessels
themselves are always so narrow that they can never be
seen on a transverse section of the organ with the
unaided eye. The microscope, however, shows that
they may be of very different diameter in the same
plant. In the roots, shoot-axes, and nerves of the leaves,
run thicker tubes, from which thinner and yet thinner
ones arise. The substance of the walls of the tubes always
consists of soft cellulose, sometimes capable of swelling ;
they are never lignified, suberised, or otherwise essentially
altered by infiltration. One of the most prominent
characteristics of the laticiferous vessels is their continuity
throughout the whole plant, or at any rate over wide areas.
This may obviously, even if not in every point, be closely
compared with the vascular system of an animal. . . .
ANIMAL AND VEGETABLE
127
If it were possible by any means to destroy all the other
tissues of such a plant as a large Euphorbia or Asclepias,
the entire form of the plant would still be preserved as a
mass of very fine threads of various thickness, representing
the ramifications of the original latex-cells ; just as the
injected vascular system of a vertebrate animal after the
removal of all other tissue allows the whole organisation of
the body to be recognised. . . . The laticiferous vessels
contain two essentially different groups of substances :
those which are again utilised in metabolism (proteids,
carbo-hydrates, fats, ferments), and those which must be
regarded as excreta useless in metabolism (resins, gums,
alkaloids, etc.).
ANIMAL
VEGETABLE
Fig. 66.
Injected blood-vessels of a human
muscle. (After Landois and Stir-
ling.) (Kolliker.)
Fig. 67.
Section from Scorzonera his-
panica showing reticulately united
latex vessels. (After Strasburger.)
" The green vegetables are particularly rich in salts,
which resemble the salts of the blood ; thus, dry salad is
said to contain twenty-three per cent, of salts, which
closely resemble the salts of the blood."
Given the necessary patience, I have no doubt that
128 STUDIES IN ELECTRO-PHYSIOLOGY:
many other examples could be found, but the foregoing
should be in themselves sufficient to establish the point I
have been endeavouring to make.
Unfortunately it is not always possible to find parallel
illustrations, but I may take the opportunity afforded by
this chapter to give the views of some authorities upon
points of resemblance between animal and vegetable
organisms. In Vegetable Physiology, by J. R. Green,
F.R.S., I find the following : " If we turn to the reaction
of the leaf of the Dion&a to contact, we find that the whole
leaf may be somewhat roughly handled without closing,
so long as no contact is made with the hairs, three in
number, which arise on a particular portion of the blade.
So soon, however, as one of these is touched, the leaf closes.
" It is impossible to avoid the conclusion that we have
to do in these instances, which are only representative
ones, with a localisation of sensitiveness, or the differentia-
tion of sense-organs. . . . The power of sight is very
complete in the higher animals . . . but in the lower
animals it becomes less and less perfect, till in some it goes
probably little further than the power of appreciating light.
This power we have seen to be possessed by certain parts
of the young seedlings of various plants in a very high
degree, and by other organs to a less extent. The sense of
touch may be compared with the power of responding to
the stimulus of contact shown by tendrils and by the tips
of roots ; the muscular sense, or power of appreciating
weight, is perhaps comparable to the property of respond-
ing to the attraction of gravitation, while the chemotactic
behaviour of certain organisms suggests a rudimentary
power of taste or smell, or both. ... If we turn to a
second feature of the nervous system, we find that the
motor mechanism of the plant seems at first to be entirely
different from that of the animal. Closer consideration,
however, lessens the difference considerably. The motor
ANIMAL AND VEGETABLE
129
mechanism of an animal is very largely either muscular or
glandular. /The contractile power is but little developed
in vegetable protoplasm, and when present it seems to be
rather passive than active, to produce frequently recoil
rather than true contraction. Still, the latter is not
entirely absent. . . . Though the power of contraction is
comparatively seldom found, it has its representative in
the power which vegetable protoplasm possesses of resisting
or assisting the transit of water. . . . The main require-
ment of most animals is freedom of locomotion or rapid
assumption by the body of new positions. The most
important duty of the plant is the regulation of the water
supply upon which its constituent protoplasts are so
dependent." This is chiefly, if not entirely, accomplished
by means of the stomata upon the under surface of the
leaves, which open or close in accordance with the require-
ments of the plant. Three of these are shown in the
following figure :
Crt&zrcf Cetts
Fig. 68.
Surface view of part of the tinder surface oi a leaf, showing three
stomata in different stages of opening and closing. (After Green.)
" The effects of stimulation may be seen in glandular
organs in plants as well as animals. Both Drosera and
K
130 STUDIES IN ELECTRO-PHYSIOLOGY:
Dioncea are excited by contact to pour out on to the surface
of their leaves acid digestive secretions, which are the
result of changes in the activity of the gland-cells.
" The conduction of the stimuli received is due in
.animals to the existence of differentiated nerves. The
way in which it is carried out in plants has been much
debated, but since the discovery of the continuity of the
protoplasm through the cell -walls there is little doubt
that we have here a similar mechanism. . . . Though
there is no particular differentiation of an anatomical
character in any "of the sense-organs of a plant, there is
nevertheless a differentiation of a physiological nature in
the direction of sensitiveness, which will equal if not surpass
the powers of the sense-organs of an animal. The tendril
of Passiflora appreciates and responds to a pressure which
cannot be detected by even the human tongue ; the
seedlings of Phalaris readily obey the stimulus of an
amount of light which is hardly perceptible to the human
eye. Many plants readily detect and respond to the ultra-
violet rays of the spectrum, which are utterly invisible
to man."
In his thirty-fourth lecture, General Considerations of
Irritability,* Sachs said : " Returning from these general
considerations to definite comparisons between the animal
and the plant, I would make special mention of that
exceedingly remarkable phenomenon in animal life, termed
by its great discoverer, Johannes Miiller, the specific
energies of the sensory nerves. As is well known, we
understand by this fact that for instance the optic nerve
responds to any given excitation whatever with the sensa-
tion of light : true, this sensation is as a rule called forth
by the vibrations of the luminiferous ether, but even
electric currents or mere concussion or diseased conditions
impel the optic nerve to the sensation of light. In the
* The Physiology of Plants.
ANIMAL AND VEGETABLE 181
same way the auditory nerve is impelled to the perception
of sound, not merely by waves of sound, but by every
change which affects it, and similarly with the remaining
organs of sense.
" Now I pointed out years ago that even the organs of
plants are provided with similar specific energies. Irritable
organs in plants are, indeed, like the sense-organs of
animals, sensitive to a definite category of stimuli, but
they can very often be affected by other stimuli also, and
in this case the stimulation is always the same. This
appears most distinctly, for example, in the case of growing
internodes and leaves. If they are illuminated from one
side they become curved, and if brought out of their
normal position they are caused to make exactly similar
curvatures : the one mode possible for responding to any
stimulus whatever is simply this curving. The matter
only obtains its full significance by the fact that every
individual plant- organ responds to the influence of light as
well as to that of gravitation in a mariner specifically
peculiar to it, and it is upon this that the anistropy of the
parts of plants depends. No less clear is the specific
energy of tendrils. . . . The identity of the effect of
stimulation in cases where totally different stimuli act on
the growing root-tips is particularly striking. . . . The
organ possesses only one mode of responding to stimuli of
the most various kinds. . . . The organism itself is only
the machine, consisting of various parts, and which must
be set in motion by the action of external forces : it de-
pends upon its structure what effects these external forces
produce in it.
" It would betray a very low level of scientific culture
to see in this comparison a degradation of the organism,
since in a machine, although only constructed by human
hands, there lies the result of the most profound and care-
ful thought and high intelligence, so far as its structure is
132 STUDIES IN ELECTRO-PHYSIOLOGY:
concerned, and in it there subsequently become effective
the same forces of Nature which in other combinations
constitute the vital forces of an organ. . . . We are
warranted in regarding the so-called spontaneous or
independent periodic movements " (in plants) " as phe-
nomena of irritability, just as animal physiologists place
the periodic pulsations of the heart in the series of phe-
nomena of animal irritability. ... I have repeatedly had
cause to refer to certain resemblances between the phe-
nomena of irritability in the vegetable kingdom and those
of the animal body, thus touching a province of investiga-
tion which has hitherto been far too little cultivated. 99
Consideration of enzyme action does not cpme within
the scope of these studies, but it appears to be common
to both animal and plant. According to Vines the chief
kinds of enzymes which have been found in plants are :
" (1) Those which act on carbohydrates, converting
the more complex and less soluble carbohydrates
into others of simpler composition and greater
solubility.
" (2) Those which act on fats, decomposing them into
glycerine and fatty acid.
" (3) Those that act on glucosides, glucose being a
constant product.
. " (4) Those that act on the more complex and less
soluble proteids, converting them into others
which are more soluble and probably less, com-
plex, or decomposing them into non-proteid
nitrogenous substances (amides, etc.)."
As regards a comparison of fats in animals and plants,
Sachs showed as long ago as 1858 that in the germination
of seeds containing fat, a transference of the fatty oils from
the cotyledons, or from the endosperm into the growing
parts of the seedling, appears to take place, and this was con-
firmed by chemical analysis by Peters. In his twenty-first
ANIMAL AND VEGETABLE 133
lecture Sachs said : " It appears that the fats can pass
through the closed tissue-cells as such ; though of course
the greater part of them is transformed into starch and
sugar for transport and use. Similar phenomena with
respect to fats occur moreover in the animal body, where
the fats entering into the stomach are in the first place
emulsified by the secretion from the pancreas, that is,
they become converted into exceedingly fine drops and
then saponified. . . . The presence of fats in the seedling
can only be explained by assuming that glycerine and
fatty acids travel from cell to cell, and are continually
becoming reunited for the formation of fat."
In the case of plants in dry climates, or so situated that,
for any reason, transpiration from their outer surfaces
must be diminished, they are characterised by the greatly
thickened and cuticularised walls of their epidermal cells.
Deposits of wax are also present in the cutinised layers of
the epidermis, and consequently water will flow off from
the epidermis without wetting it. The wax is sometimes
spread over the surface of the cuticle as a wax covering.
This is the case in most fruits, where, as is so noticeable in
plums, it forms the so-called bloom. (Strasburger.)
There can, I think, be no doubt that the main purpose
underlying the provision of the wax covering of fruits is
the preservation of their absolute insulation, and one can
be sure, even without examination, that where the outer
skin or rind of a fruit is of comparatively delicate texture
as of the plum while the fruit itself is juicy and highly
conductive, the protective " bloom " will be found to be
most abundantly provided.
There is at least some analogy between this and the
sebaceous secretion of the human epidermis ; both are
apparently designed for the performance of the same
function.
In cases where wax is absent or in greatly diminished
134 STUDIES IN ELECTRO-PHYSIOLOGY:
quantity, protection of a similar nature is afforded by resin,
or by a covering or capsule of a fibrous character, as, for
instance, in the leaf of the ivy and the capsules of various
beans and seeds, etc.
In regard to the comparison by Sachs of the laticiferous
vessels of plants to blood-vessels of vertebrate animals, he
instanced the fact that when a milky stem is cut not only
the low cut surface of the apical portion but the upper one
of the root-stock also extrudes the latex. Besides, the
laticiferous vessels are extremely narrow capillary tubes,
the normal terminations of which in the buds, leaves, and
root-apices are closed. How, he asked, could fluid flow
out at all on cutting such capillaries closed at the ends
unless the fluid was under pressure ? " When we wound
Fig. 69. Fig. 70.
Cells from the leaf of Elodea ; Two cells from a staminal hair
p, protoplasm. of Tradescantia.
ourselves the blood does not simply flow out, it is driven
out."
ANIMAL AND VEGETABLE 135
In regard to the movement of protoplasm in plants
some interesting facts are given by Green. In cells from
the leaves of Elodea and the staminal hairs of Tradescantia,
to take two examples, the current appears to circulate,
as will be seen from the two figures on the preceding page.
The same author has much to say upon the subject of
rhythmic movement in plants. " If we look back,*' he
writes, " to the behaviour of the contractile vacuole of
chlamydomonas, we are struck by the fact that its pulsations
occur with a certain definite intermittence so long as
they are not interfered with by external conditions. The
vacuole dilates slowly, reaches a certain size, and suddenly
disappears ; then is gradually formed again, and the series
of events is repeated. This regular intermittence con-
stitutes what is often spoken of as rhythm. The rhythm
which is so easily seen in the case of pulsating vacuoles is
characteristic also of those less obvious changes in proto-
plasmic motility which lead to the variations of turgidity
in different organs, particularly in those which are growing.
During the growth in length of a symmetrical organ, such
as a stem or root, the apex points successively to all points
of the compass. This is the result of a rhythmic variation
of the turgidity of the cells of the cortex. If we consider
a longitudinal band of such cells, we find that at a certain
moment the cells are at their point of maximum turgidity,
and the growing apex is made to bend over in a direction
diametrically opposite to this band. The turgidity of this
band then gradually declines to *a minimum, and again
increases slowly to a maximum. If we conceive of the
circumference of the organ as divided into a number of such
bands, we can gain an idea of the changes in turgidity
which cause the circumnatation. Each band is in a
particular phase of its rhythm at any given moment, and
the successive bands follow one another through the phases
of their rhythm in orderly sequence, so that when one is at
136 STUDIES IN ELECTRO-PHYSIOLOGY:
its maximum, another diametrically opposite to it is at its
minimum. The phases of maximum and minimum tur-
gidity thus pass rhythmically round the organ, and the
apex is consequently compelled to describe a spiral line as
it grows. ... It is not infrequent for the rhythmic change
in the turgescence to affect only two sides ... its changes
will thus resemble, those of a flattened organ which can
only be made to oscillate backwards and forwards."
Until I read Green's Vegetable Physiology I was not
aware that this rhythmicality of movement had been
observed, but the subject is to me one of peculiar interest.
It so happens. that some years ago I carried out a series of
galvanometric tests with plants invariably at night
and took note of phenomena which, in their electrical
aspect, were suggestive of rhythmic inspiration and
respiration.'
The paralysis or destruction of protoplasmic movement
in both animal and vegetable bodies appears to occur from
identical causes, as will be seen on reference to the Study
of Amoeboid Movement.
One question which has engaged my attention is :
Can there be any analogy between the propagation of
impulse in mammal and plant ? Though the possession of
nerves is denied to the latter by some authorities, there is
little if any doubt that they are present in a rudimentary
form, and in such case the propagation of stimuli should,
logically, be possible.
Green remarks : "In considering broadly the result
of stimulation " (of plants) " we must notice at the outset
that it provokes a purposeful response. The living
substance appears to have a definite aim."
" If any one of the small leaflets of a leaf, on a shoot of
Mimosa with five or six leaves, is stimulated by means of
the hot focus of a burning glass, all the other leaflets of the
same leaf gradually fold together, and after a time the
ANIMAL AND VEGETABLE 137
large motile organ at the base of the main petiole also
becomes bent, and again after a few seconds the stimulation
extends to the nearest neighbouring leaf, then to the
succeeding one, and so on, till at last all the leaves of the
shoot have made the movement/' (Sachs.)
The rate of propagation of stimuli in the plant, as
compared with man, is, of course, relatively very slow.
That is, if we regard it as a purely physical process in the
sense that when a stretched string is jerked at one point
the whole string vibrates. But if we take the rate of
conduction of a feeble electrical stimulus, I do not think it
will be found to differ materially from the rate of conduction
in a human nerve.
138 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER X
AMCEBOID MOVEMENT
" THE protoplasm tends during life to exhibit move-
ments which are apparently spontaneous, and when the
cell is uninclosed by a membrane a change in the shape, or
even in the position of the cell, may be thereby produced."
(Schafer.)
One of the constituents of cell-protoplasm is called
nucleo-protein, and the normal supply of iron to the body is
contained in the nucleo-proteins of plant and animal cells.
A cell possesses the power of breathing, i.e., taking in
oxygen.
" There is no doubt that protoplasmic movement is
essentially the same thing in both animal and vegetable
cells. But in vegetable cells the cell-wall obliges the
movement to occur in the interior." (Halliburton, 1915.)
What is the nature of that movement ? I learn from
the same source that if a living amoeba is watched for a
minute or two, an irregular projection is seen to be gradu-
ally thrust out from the main body and retracted, a second
mass is then protruded in another direction, and gradually
the whole protoplasmic substance is, as it were, drawn into
it. The amoeba thus comes to occupy a new position,
and when this is repeated several times we have locomotion
in a definite direction, together with a continual change of
form. (Halliburton, 1915.)
Is it not possible to explain this movement by the
electrical law of attraction and repulsion ? Iron, as I have
ANIMAL AND VEGETABLE 189
remarked elsewhere, is fifth in the scale of electro-positives
and oxygen at the bottom of the list of electro-negatives ;
and providing that osmosis can take place and there is an
exciting solution, such electrical action may very well occur.
Upon the assumption that it does so occur let us see
how the movements of the amoeba are affected by stimuli.
" (1) CHANGES OF TEMPERATURE. Moderate heat
acts as a stimulant. The movement stops when the
temperature is lowered near the freezing-point or raised
above 45 C.
" (2) CHEMICAL STIMULI. Distilled water first stimu-
lates, then stops amoeboid movement. In some cases
protoplasm can be almost entirely dried up, but remains
capable of renewing its movement when again moistened.
Dilute salt solution and very dilute alkalies stimulate the
movements temporarily. Acids or strong alkalies per-
manently stop the movements ; ether, chloroform . . .
also stop it for a time.
" Movement is suspended in an atmosphere of hydrogen
or carbonic acid, and resumed on the admission of air or
oxygen ; complete withdrawal of oxygen will after a
time kill protoplasm.
" (3) ELECTRICAL. Weak currents stimulate the move-
ment, while strong currents cause the cells to assume a
spherical form and to become motionless."
I will repeat, but paraphrase, the foregoing
(1) Change of Temperature. Moderate heat acts as a
stimulant by lowering internal resistance. The movement
stops when the temperature is lowered near the freezing
point because of the enormous increase of internal resist-
ance so created, and as protoplasm dies at 45 C. (or
thereabouts), that temperature would naturally bring
about cessation of movement by killing the protoplasm.
(2) Chemical Stimuli. Distilled water, regarded as a
foreign substance or fluid, may bring about a momentary
140 STUDIES IN ELECTRO-PHYSIOLOGY:
disturbance, but by reason of its high resistance would tend
to stop movement after a short time. In some cases
protoplasm can be almost entirely dried up, but remains
capable of renewing its movement when again moistened-
Its electrical activity and especially capacity is depen-
dent upon the presence of conductive moisture, and when
not so moistened it would become inert. That dilute salt
solution and very dilute alkalies stimulate the movements
temporarily by lowering internal resistance is what might
reasonably be expected. As, however, there would be
some alteration of the chemical composition of the cell-
contents the efficiency of the cell would no doubt be ulti-
mately impaired. Obviously also acids or strong alkalies
would permanently stop the movements by causing
diffusion ; ether and chloroform, as is well known, interfere
with conduction, and, moreover, I am quite sure that the
least trace of tincture of nux vomica would be fatal.*
That movement is suspended in an atmosphere of
hydrogen or carbonic acid calls for no explanation, but the
fact that complete withdrawal of oxygen will, after a time,
kill protoplasm is a strong argument in favour of the
hypothesis that movement is due to electrical action.
(3) Electrical. Weak currents, by supplementing the
natural energy of the cell, stimulate the movement, but
strong currents paralyse the protoplasm, or by disrupting
its electrical structure cause it to revert to its original
shape when at rest.
In considering the theoretical solution I have offered
of amoeboid movement, it is as well to bear in mind that
although the chemical composition of the dead amceba can
be resolved by analysis, such is not the case with the living
amceba, in which, in all probability, these chemical sub-
stances are represented by their groups of ions. If that i s
so it can readily be imagined that, with a constant intake of
* See experiment with begonia (p. 159).
ANIMAL AND VEGETABLE 141
oxygen, a complex electro-chemical action between it and
the iron in the cell may be set up, which by attraction and
repulsion gives rise to the observed phenomena.
In this connection reference may usefully be made to
the experiments of Ampere. He proved by means of
movable wires that attraction was shown when the currents
ran in the same direction and repulsion when in opposite
directions ; also that when two finite currents are inclined
to each other without crossing, they attract when both run
towards or both run away from the common apex, but
repel when one runs towards and the other away from the
apex.
When the currents are in the same direction, the
surfaces oppositely electrified will be directly opposed,
and therefore attraction ensues. If the currents are in
opposite directions the surfaces similarly electrified will
oppose, and therefore repel each other.
In protoplasm there are many possible " surfaces " in
the form of more or less vertical divisions of the cell.
Supposing amoeboid movement to be due to either
attraction or repulsion, or both, causing the irregular
projections, we can understand that upon one current
momentarily ceasing to flow or diminishing in intensity
such projection would, wholly or partially, be withdrawn,
because it had its origin in the first instance in a force, and
upon that force being no longer operative or altering in
intensity a change of form would take place.
It will be remembered that early in the last century
Davy passed a current through a solution of potash, and
finding that the potassium went to one of the poles and the
oxygen to the other, concluded that the two elements of a
compound are charged with different electricities, which
are neutralised on combination. That is the view now
held after so long, and so lamentable a loss of time.
" The actual theory of ionisation may be summed up
142 STUDIES IN ELECTRO-PHYSIOLOGY:
in the following statement, which does but repeat exactly
the ideas of Faraday : Bodies are composed of elements
or ions charged, some with positive, others with negative
electricity, and united at first in the neutral state. Under
the influence of the battery current, the neutral molecule
dissociates into positive and negative elements, which go to
the poles of contrary names. The decomposition of a
neutral salt may be represented by such an equation as :
N0 3 K = N + 8 + K
" When an ion leaves a solution in order to precipitate
itself at an electrode charged with electricity of contrary
sign by reason of the attraction exercised between two
opposite electric charges it then becomes neutralised,
which means that it receives from the electrode a charge
exactly equal but of contrary sign to that which it before
possessed.
" Adopting the theoretical ideas put forward by
Clausius, Arrhenius recognised that an electric current was
in no way necessary to produce the dissociation of com-
pounds into ions. In dilute solutions the bodies dissolved
must be separated into ions by the mere fact of solution.
When the electrodes of a battery are plunged into such
solution, the ions must simply be attracted by them
the positive ions by the negative pole, and the negative ion
by the positive pole." (Le Bon.)
According to Czapec, in any solution the degree of this
dissociation depends on the nature of the salt, the tempera-
ture of the solution and its strength. Acids and alkalies
when diluted to one milligramme in one litre of water are
entirely broken up into ions and cease to exist as acids and
salts. Halliburton tells us that the proportion of inorganic
salts in the blood plasma is 8-55 in 1,000, or approximately
0-9 per cent. ; but that is the sum total of all the salts.
ANIMAL AND VEGETABLE 143
I do not know what the percentage of alkali in the cell-con-
tents may be. In any case there must be a certain amount
of electrolysis due to the body current and irrespective of
intra-cellular action. In blood plasma sodium is present to
the extent of about 0-334, potassium 0-032, and chlorine
0-364 per cent.
As regards rigor, or cessation of protoplasmic move-
ment in plants, Sachs gives the following information :
(1) Temporary cold-rigor occurs in the motile organs
of Mimosa pudica, when the temperature remains for some
hours below 15 C. The lower the temperature falls below
15 C. the more rapidly the rigor sets in.
(2) Temporary heat-rigor occurs in Mimosa, in moist
air at 40 C. within one hour ; in air at 45 C. within thirty
minutes ; in air at 49-50 C. within a few minutes. The
irritability returns after a few hours in air at a favourable
temperature.
Rigor is also caused by the withdrawal of oxygen ;
when brought into the air the plant again becomes motile.
Irritability disappears in hydrogen and nitrogen in carbon
dioxide and ammonia, but returns on free exposure to air.
Carbonic oxide gas mixed with air to the extent of twenty
to twenty-five per cent, destroys the irritability.
" The vapours of chloroform and ether suspend the
irritability of the motile organs (for variations of light
also), without destroying the life, if the effect does not
continue too long.
" Temporary rigor due to electric influence was found
by Kabsch to occur in the gynostemium of Stylidium. A
feeble current acted as a stimulus like vibrations ; a
stronger one caused a loss of irritability, which returned
again, however, after half an hour."
144 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER XI
THE ELECTRO-PHYSIOLOGY OF THE
MOTOR APPARATUS
MUSCULAR TISSUE.
THE two chief varieties of muscular tissue are
(1) Unstriped or involuntary muscle, i.e., not under
the control of the will.
(2) Striped or voluntary.
In non-striated muscular tissue the cell substance is
longitudinally but is said to be not transversely striated, and
each cell seems to have a delicate sheath. Between the
fibres there is a small quantity of cementing substance.
Non-medullated nerves are supplied to plain muscular
tissue from the sympathetic or ganglionic system, and this
tissue responds but slowly to a stimulus ; the contraction
spreading as a wave from fibre to fibre.
As it may help us to a clearer understanding of the
functioning of the motor apparatus as a whole, we will first
consider striated tissue.
STRIATED MUSCULAR TISSUE.
Up to this moment I had not seen, in any work upon
Physiology, any illustration of the structure of muscular
tissue, but as an electrician I knew what I should find when
I betook myself to study. I should find sets of con-
densers of varying capacity, with an elastic (compressible)
substance between each condenser, and with absolute,
ANIMAL AND VEGETABLE 145
elastic, sheath insulation ; the whole being so arranged as
to be capable of neuro-electrical contraction in almost
every direction. The chain of condensers might, indeed,
contract more suddenly, or violently, at one point than at
another point or points, but the various contractions would
be designed to give, under impulse, a certain definite
movement or series of movements to the muscle under
excitation.
I now learn from Landois and Stirling's Text-book
of Human Physiology that each muscular fibre receives
a nerve-fibre, or wire from a central station or
stations.
The elastic sheath is called sarcolemma, and has
transverse partitions stretching across the fibre at regular
intervals. Within the sarcolemma is the contractile
substance of the muscle. This, sarcous, substance is
marked transversely by alternate light and dim layers,
stripes, or discs.
These muscular compartments contain the sarcous
substance, and in each compartment there is a broad dim
disc, forming the contractile, or compressible, part, on the
upper surface, as shown in the illustration (p. 147) ; then,
lower down, a narrower, " clear," homogeneous, soft or fluid
substance ; then a membrane (called Krause's membrane),
and another clear substance, followed by a dim (com-
pressible) disc, and so on throughout the fibre.
Let us imagine the sarcolemma to be composed of
india-rubber, at all events on its inner side, the dim
substance to be an elastic buffer, the " clear " lines to be
conducting plates or discs, and Krause's membranes or
Dobie's lines to be dielectric in character, and condenser
action is suggested, once it is conceded that the impulse is
neuro-electrical. It is not a question, as I have argued in
another chapter, of whether the impulse is neuro-electrical
or chemical, but of which action is precedent.
L
116 STUDIES IN ELECTRO-PHYSIOLOGY:
It will be useful at this stage to bear in mind certain
electrical laws
(1) The amount of electricity induced by an electrified
body on surrounding conductors is equal and
opposite to that of the inducing body.
(2) Induction leads to discharge as well as charge.
At contact, or within a distance bridgable by the
tension, the charge would be neutralised.
(8) Faraday called the medium through which induc-
tion is propagated, such as air, shellac, paraffin
wax, etc., the dielectric. Air is taken as 1 and
all other substances as more than 1. Air, there-
fore, is only a bad conductor, not a non-
conductor.
(4) Faraday further supposed the particles or mole-
cules of the dielectric to be conductors insulated
from each other ; and to this discovery we owe
the condenser, and the Farad as the unit of
capacity.
(5) Induction propagates itself in the direction where
it has the least resistance to encounter.
(6) The charge that a body receives is always in
proportion to the facilities it offers for induction.
If a body is so situated that it has nothing to act
on, it receives no charge, or, in other words, has
no inductive capacity.
(7) Discharge begins where the tension is greatest.
(8) The greater the surface over which electricity is
diffused the less its tension at any particular
point, and vice versa.
(9) Electricity is exhibited only on the surface of
conductors.
(10) The distribution of electricity on the surface of
insulated conductors is influenced materially by
their form.
(11) Electricity concentrates on points and pro-
jections.
ANIMAL AND VEGETABLE 147
The sarcomeres, or divisions, of muscular fibre are
shown thus
and such a fibre consists of a number of these divisions, of
varying diameter and area, a is the dim, contractile
part, b the clear substance, and c Krause's membrane or
Dobie's line. We have it on the authority of Noel Paton that
the sarcolemma is " a delicate, tough, elastic membrane,
closely investing the fibre, and attached to it at Dobie's
lines.''
Sharpey's drawings of a portion of a human muscular
fibre, A, and of separated bundles of fibrils, B, are shown
on the next page.
The motor nerves of voluntary muscle are efferent, and
therefore the impulse is from the brain, downwards.
Suppose, then, we connect these sarcomeres in series in a
battery circuit, thus :
JSarffi
Earth
71.
The law of electrical attraction would at once come into
play. The upper plate would induce electricity of equal
148 STUDIES IN ELECTRO-PHYSIOLOGY:
js
a
-C
6
JarcolemmoL
Fig. 72
Fig. 73.
Physiological Explanation. A = portion of a human muscular fibre ;
B = separated bundles of fibrils : a, a, larger and rf, c, smaller collections.
In A the letters a, 6, and c represent the dim space, the clear spaces,
and Krause's membrane respectively.
Electrical Explanation. In C the letters a, b, and c denote : a, a com-
partment filled with an elastic substance, say, viscous india-rubber solution ;
6, metallic or other conducting plates ; and c, waxed paper or other dielectric
material.
ANIMAL AND VEGETABLE
149
tension but of opposite sign at the lower plate, and that
impulse would be transmitted throughout the series, with
the result that contraction would take place, and the spaces
a be compressed and bulge at the sides, while the sarco-
lemma would also be contracted.
The effect would, in fact, be like the compression of a
concertina
\
Fig. 74.
CONCERTINA EXPANDED.
Fig. 75.
CONCERTINA COMPRESSED.
except that the projections of the bellows would be rounded
instead of diagonal, and assume the appearance of the
following figure:
Fig. 76.
But this would only give us a straight " pull," and as a
muscle does not respond to impulse in that way, we must
see how Nature overcomes the difficulty, and how discharge
or neutralisation is brought about.
From Fig. 72 (B) we see that the fibrils (and it must
150 STUDIES IN ELECTRO-PHYSIOLOGY:
include the fibres) are of varying diameter, and we have
learned that (1) tension is in the inverse ratio to the surface
over which electricity is distributed, (2) electricity concen-
trates on points or projections, and (3) discharge begins
where tension is greatest.
If we were making an artificial muscular fibre we could
solve the problem of discharge or neutralisation of charge
by placing studs upon our conducting plates, as in Fig. 77
because as electricity concen*
^ mm *** **, fates on points or projections,
and discharge begins where the
tension is greatest, the plates
would discharge when, by
attraction, they approached each other sufficiently.
We could also vary the " pull " both as regards strength,
or velocity, and direction, first by varying the area of some
of the sarcomeres, and second by joining them up in group 8
in series or series-parallel, or parallel.
That Nature does the first is obvious from Fig. 72 (B).
As regards the second, we are told that the nerve-fibres
of voluntary muscle pierce the sarcolemma and terminate
in end-plates, which are shown to connect up with different
groups of the sarcomeres of muscular fibre in the following
manner :
Jfervefibres
Fig. 78.
Not only is that so, but, if it were desired, the Afferent
impulse could be converted to an afferent one at any point
ANIMAL AND VEGETABLE
151
by the simple process of inserting a condenser in the
nerve circuit :
Fig. 79.
or, as it appears to be accomplished in the human body :
Fig. 80.
both, however, are on exactly the same principle.
We will now compare, briefly, Nature's method of
discharge or neutralisation of charge with my suggestion of
'* studs," and discuss the whole question in detail later on.
As given by Schafer the sar comer e in a moderately
extended condition is shown thus :
Fig.pl.
k, k are Krause's membranes or Dobie's lines, H the
plane of Hensen, and SE a poriferous sarcous element.
152 STUDIES IN ELECTRO-PHYSIOLOGY:
B depicts the sarcomere in contracted condition,
compressed and elongated and bulging at the sides.
The analogy between
metallic plates and the
" clear " spaces, b, of the
sarcomere cannot, of
course, apply to the
Fig * 82 * material employed, but
only to its electrical character. I am informed that
the " clear " spaces are largely composed of potassium
salts in fluid or semi-fluid form, and that the dark
vertical lines are canals or pores, open towards Krause's
membrane, but closed at Hensen's line. The clear
spaces are therefore conductive, and the analogy, elecitri-
cally, holds good. In the contracted muscle the clear
part of the muscle substance passes into the canals or
pores and disappears from view, swelling up and widening
the sarcous element and shortening the sarcomere. In the
extended muscle, on the other hand, the clear substance
passes out from the canals of the sarcous element and lies
between it and the membrane of Krause, again ready
for action.
The effect of the completed contraction is to cause the
conducting plates to approach each other near enough to
enable them to discharge or neutralise their charge by
contact through some invisible pore in Hensen's line ; or,
possibly, by osmosis or diffusion.
Alternatively such action may be made to occur by
the plates being withdrawn to a sufficient distance to cause
induction to cease. Then, the impulse having pa'ssed,
they would be restored to their former position, in readiness
to resume the performance of their function.
In this connection we may recall the " Muscle telegraph "
of Du Bois-Reymond. He attached a piece of muscle to
a movable disc and placed the former in the circuit of a
ANIMAL AND VEGETABLE
153
Ley den jar. When connection was made the muscle
contracted and the disc was made to move. With two
muscles and two discs, battery power, and suitable means
for the rapid neutralisation of charge, an electro-mechanical
apparatus to exhibit signals in the Morse Code could easily
be made.
I have no information as to the composition of Krause's
membrane, but if it does not exist and is not a bad con-
ductor of neuro- electricity, then the problem of muscular
contraction offers the most extraordinary series of coinci-
dences I ever heard of. In considering this point, how-
ever, it must be remembered that a good conductor of high
may not conduct low tension electricity at all.
So far, in speaking of the clear spaces, I have used the
words " plates " and " discs, " but am by no means sure
that I am correct in doing so. Schaf er gives an illustration
in which the arrangement of the conducting elements
Fig. 83. PORTION OF LEG-MUSCLE OF INSECT TREATED WITH DILUTE ACID.
S, sarcolemma ; D, dot-like enlargement of sarcoplasm ; K, Krause's
membrane. The sarcous elements are dissolved or at least rendered
invisible by the acid. (Schdfer.)
appears to my mind to be more consistent with the
force exerted by muscle under what must be considered
154 STUDIES IN ELECTRO-PHYSIOLOGY:
comparatively feeble stimulus. Electricity concentrates on
points and projections, and in that connection the figure
assumes a more than usual importance.
We may now study the physiology of muscular fibre
to see if there are any accepted facts or views which are
antagonistic to ours, and if so, whether they are susceptible
of explanation other than that given by the physiologist.
" A nerve-fibre usually enters a muscle at the point
where there is the least displacement of the muscular
substance during contraction.'*
The electrician would, of course, connect his line or
battery wire in such manner as to avoid interference with
the movable or active part of the apparatus.
The next paragraph, from Landois and Stirling, will, I
fear, bring me into direct conflict with some accepted views.
44 Stimuli are simply various forms of energy, and they
throw the muscle into a state of excitement, while at the
moment of activity the chemical energy of the muscle is
transformed into work and heat, so that the stimuli act as
discharging forces . . . the excitability varies as the
temperature rises or falls."
I cannot agree with the view that stimuli are variou*
forms of energy, holding, as I do, that they the natural
stimuli are manifestations of neuro-eiectrical energy ;
although certain chemical changes are undoubtedly con-
sequent upon them.
Again, it is not altogether correct to say that stimuli
act as discharging forces. They act first as charging
forces, and when contraction has taken place and not
before cause, as a result of that contraction, discharge
or neutralisation of charge.
In regard to the effect of temperature upon the ex-
citability of muscular fibre the explanation can, I venture
to think, be given in three words, i.e., 4t Heat assists
conduction."
ANIMAL AND VEGETABLE 155
With a rise of temperature the resistance of the clear
substance of the muscle and of Krause's membranes would
be reduced ; with a fall of temperature the resistance of
both would be increased. What the relative fall or rise of
resistance is I have no means of determining, but, broadly
speaking, a considerable rise of temperature might seriously
impair the action of the condenser-compartments (sar-
comeres) by breaking down the resistance of Krause's
membranes, and so, wholly or partly, short-circuiting the
condensers ; while a considerable fall of temperature
might increase the resistance of the clear substance to such
an extent that the low-tension nerve-charge could not
overcome it, with the result that the muscle would,
temporarily, become paralysed.
A further section deals with excised muscles, and lays
stress upon the fact that a series of stimuli of the same
strength causes a series of contractions which are greater
than at first (Wundt), and argues from that, that although
the first feeble stimulus may be unable to discharge a
contraction (? cause a contraction) the second may, because
the first one has increased the muscular excitability (Fick).
By excised muscles I understand dead muscles. There
is an essential difference between the living and the non-
living ; but even in non-living muscular fibre we should
have condenser-action while its structure remained un-
impaired. But it does not follow that the conductivity of
the clear substance and the resistance of Krause's mem-
branes would be exactly the same as in living muscle^
Discharge cannot occur until contraction is completed,
and whereas in living muscle one impulse may be sufficient,
a dozen or more might, conceivably, be conveyed to dead
muscle before contraction could be completed and dis-
charge or neutralisation effected if its capacity is altered
by death, or some change is brought about by death in the
elasticity of the sarcous substance.
156 STUDIES IN ELECTRO-PHYSIOLOGY:
Reading on, we are told that " if the muscles of a frog
(Du Bois-Reymond) or tortoise (Briicke) be kept in a cool
place, they may remain excitable for ten days, while the
muscles of warm-blooded animals cease to be excitable
after one and a half to two and a half hours. ... A
muscle when stimulated directly, always remains excitable
for a longer time when its motor nerve is already dead."
I have tested toads and tortoises galvanometrically in
years gone by, and have been astonished at their super-
abundant nerve energy as compared with that of man.
Moreover, their insulation, absolute and internal, is such
that they can withstand extremes of temperature and exist
without food for incredible periods of time. To compare
the muscle of a tortoise with that of a warm-blooded animal
is to compare an ivy leaf with a deciduous leaf. By
reason of its higher insulation the former will live (i.e.,
remain excitable) for months, whereas a horse-chestnut
leaf will perish, under the same conditions, in a few days.
It is, to my mind, purely a question of insulation. Suppos-
ing there to be any resistance remaining in Krause's
membranes and any conductivity in the clear substance,
condenser-action would continue- in some degree ; but in
the dead muscular fibres of warm-blooded animals there
would, I should think, be rapid diffusion, short-circuit, and
consequent cessation of condenser-action.
The statement that " a muscle when stimulated directly
always remains excitable for a longer time when its motor
nerve is already dead " is almost elementary. Part of the
sensory nerve of an apple is its stalk. When the apple is
ripe, and it falls, Nature seals the end of the stalk with a
resinous insulating substance. Granting, then, the sar-
comeres to be structurally intact, a dead motor nerve
would be equivalent to the sealed sensory nerve-ending of
the apple. On the other hand, if the motor nerve of the
muscle was maintained in a moist condition it would not
ANIMAL AND VEGETABLE 157
remain excitable for so long a time, nor could the apple
continue to resist decay if its stalk was unsealed and wet.
Under the heading " Independent Muscular Activity," I
am told that " there are many considerations which
show that excitability is independent of the nervous
system, although in the higher animals nerves are the usual
medium through which the excitability is brought into
action. Thus plants are excitable, and they contain no
nerves." The italics are my own, and emphasise a state-
ment upon which the whole argument depends. That
statement also furnishes another illustration of the manner
in which the student may be side-tracked from the main
line of independent thought and research. He is told by
a great authority that plants have no nerves, and, accepting
the dictum with the respect invariably accorded to the
teacher, is induced to follow a false line of reasoning.
Every plant that grows in the soil has a nervous
organisation. The earth is the negative terminal of
Nature's electrical system, as the air, in normal conditions
of weather, is the positive terminal ; and every tree,
plant, or vegetable is charged by the earth, through
sensory nerves, or closed circuits, extending from the roots
through the stem and stalks and thence to the veins
(nerve-fibres or fibrillae) of the leaves. These all yield a
negative galvanometric reaction, while those parts of the
leaves between the veins, as well as the flower end of all
vegetables arid fruits, are of positive sign. Not only have
plants nerves, but I shall be very much surprised if they
are not found to possess a lower form of motor apparatus
as well.
I am far from being alone in this opinion. Ainsworth
Davis says .
" It has been shown that the protoplasm in adjacent
cells may be permanently united by fine threads of the
same material passing through the cell -walls. For effecting
158 STUDIES IN ELECTRO-PHYSIOLOGY:
movements such an arrangement is invaluable, and this
kind of continuity seems to foreshadow the muscular
fibres of animals. . . . The ' continuity of protoplasm '
has here also an important bearing, and the nerves of
animals seem prefigured." It is known that plants suffer
from chlorosis, and that it may be cured by putting a little
soluble iron in the soil.
Also Sachs says in his Physiology of Plants : " It can
scarcely be wondered at if the conclusion is drawn that
something in the nature of nerves exists in the leaves of
Dioncea, as appears moreover to accord with the in-
sectivorous propensities of these plants. ... In any case
we have no necessity to refer to the physiology of nerves
in order to obtain greater clearness as to the phenomena of
irritability of plants ; it will, perhaps, on the contrary,
eventually result that we shall obtain from the process of
irritability in plants data for the explanation of the
physiology of the nerves."
In the vegetable world the various forms of life have
their roots in the negative soil, and embryologists have
demonstrated that their starch-sugars are of laevo- and
their albumins of dextro-rotation. Man has his roots,
so to speak, in the positive air, and the rotation of his
sugar-glycogen and albumins is directly opposite to that
of the plant. That line of thought is worth following, and
may be productive of valuable results.
A good deal has been written upon the effect of curara
upon motor nerves. My own research has shown that
certain poisons increase the resistance of the nerve sub-
stance to such an extent that the nerves are unable to
transmit impulse ; with the result that there is pain so
closely resembling that attendant upon neuritis and sciatica
as to introduce error into diagnosis. Moreover, Professor
Chunder Bose and I have both found that plants are
similarly affected. In a recent experiment I tested a
ANIMAL AND VEGETABLE 159
healthy begonia and obtained a steady deflection of
135 mm. upon the galvanometer scale. The injection of
two minims of tincture of nux vomica into the stem
reduced that deflection to zero in one hour. In six hours
the stem fell, the leaves separated at the junction of stalk
with stem, and in a week the plant was rotten.
The point laboured by at least some investigators seems
to be that although a nerve or nerves may be paralysed or
deprived of conductivity by certain poisons, the excitability
of muscle may not be so affected, and therefore the muscle
is independent of nerve.
Expose that theory to the cold light of reason. In the
first place, the poison the destructive agent must pene-
trate not only the nerve but invade the whole of the sarco"
meres as is possibly the case in gas gangrene if the latter
are to be equally affected ; secondly, if the resistance of the
clear lines of muscular fibre is correspondingly increased,
so, conceivably, would be the resistance of Krause's mem-
branes, and therefore contraction might still be possible,
though in diminished degree. If it is a matter, merely, of
poisoning, or, in other words, " sealing, " the motor nerve,
the excitability should, according to the theory I have
advanced, endure for a longer period than if the nerve had
not been poisoned or insulated.
Under the microscope single muscular fibrillae exhibit
the same phenomena as an entire muscle, in that they
contract and become thicker. Though there is difficulty
in observing the changes that occur in the individual
parts of a muscular fibre during the act of contraction, it
appears to be certain that the muscular elements become
shorter and broader during contraction ; that is to say, the
transverse striae approach nearer to each other in the
manner I have indicated.
Too much importance should not, for reasons I have
given, be attached to experiments with dead muscle unless
iCo STUDIES IN ELECTRO-PHYSIOLOGY:
the personal equation has been allowed for, but when
I'urrents of high tension are employed this may be dis-
; egarded and the data viewed from a different standpoint.
For example, an illustration of the muscle-curve produced
by the application of a single induction- shock to a muscle,
as given in Landois and Stirling, is full of interest, although
it does not seem to have conveyed its lesson.
Let us see if we can learn anything from it.
a
Fig. 84.
a/, abscissa ; ac, ordinate ; a&, period of latent stimulation ; bd t
period of increasing energy ; de, period of decreasing energy ; ef, elastic
after- vibrations.
Such is the brief explanation of the curve, but it is,
needless to say, elaborated in the text. Any electrician
acquainted with submarine cable telegraphy would,
however, have in mind what is termed inductive embarrass-
ment, and point out the well-known fact that each signal
at a receiving station (and muscle is a receiving station)
takes a longer time to leave the line than it did to enter it.
A momentary signal at starting, it becomes a prolonged
signal at its destination, and, furthermore, while a con-
denser may be partially discharged, as shown by the curve
de, almost instantaneously, it would continue to discharge
along the curve ef. All this, I contend, goes to show that
the nerve impulse is neuro-electrical, and that muscular
contraction occurs through the influence of induction upon
condenser-bodies.
ANIMAL AND VEGETABLE 161
At the risk of labouring the fact, I must repeat that the
tension at any point is in the inverse ratio to the surface-
area over which electricity is distributed. That being so
it follows, logically, that the tension at any point or points
may be varied by varying the surface-area of the conducting
plates, discs, or membranes. -
Sarcolemma and Neurilemma. I have classed these
together because, whatever differences may exist between
them, they have two properties in common, i.e., they are
both elastic and both either dielectric in character, or they
carry a dielectric substance or substances upon or in them.
If sarcolemma is not, in itself, of comparatively high
resistance it must carry, on its inner side, a resistant
substance or material, because, if it were not so carried,
contact might occur between the conducting plates or discs
or points of the sarcomeres. Also I must assume that the
sarcolemma is very elastic, and for this reason. Suppose
the sarcolemma not to exist, and that in its place was a
layer of dry (highly resistant) air. When an impulse was
sent along a motor nerve to cause contraction there would
be nothing to impede contraction, and the maximum
contractile effect would be obtained. Between this
unimpeded movement and movement governed by an
elastic material there would be a wide margin of difference
dependent upon the compressibility of the material
and Nature would adjust the degree of elasticity or com-
pressibility to meet requirements.
OTHER INSULATING PROCESSES.
Halliburton gives an illustration of a transverse section
of the sciatic nerve of a cat which will repay study.
At first sight one is forcibly reminded of a number of
bundles of insulated wires laid in bitumen in a trough,
and we shall, I think, be led to the conclusion that that view
M
162 STUDIES IN ELECTRO-PHYSIOLOGY:
is not without foundation when we examine the figure in
detail.
Let us first unravel a piece of ordinary electric-light
" flex." In the centre are a number of fine copper wires
ferineurutm
Fig. 85.
which we will call fibrillae. The first insulating layer is
composed of red cotton, and this we will imagine t9 be the
endoneurium. The next outer layer is of white cotton
(lymph space), while the outer layer or perineurium is of
green silk a very highly-resistant material.
In the illustration given above it will be seen that each
bundle of nerve-fibres is encircled by a lymph space lying
between two insulating processes (endoneurium and
perineurium), and as lymph is alkaline and therefore
conductive, another problem is presented for solution.
What, in this particular instance, is the function of
lymph ?
Suppose the nerve-fibres to be insulated wires connected
in a special circuit for a special purpose, and further imagine
these wires to run more or less parallel with hundreds or
thousands of other wires in different branch circuits, each
or all of which would be conveying currents or transmitting
impulses in the same or opposite directions. The result
would be inductive interference with the fibres of the sciatic
nerve, and the impulses transmitted by them would be
liable to continued interruption.
ANIMAL AND VEGETABLE
A practical remedy, if we were dealing with bundles of
insulated wires, would l>e to copper-tape each bundle or
put it in a metal tube, so that induced currents could be
intercepted by the tape and tube anpl prevented from
reaching the actual conductors, the wires or nerve-fibres.
That appears to be the most reasonable view to take of the
function of lymph in this case. It is hardly possible to
regard it as an insulating substance, despite its tendency to
clot and form a " colourless coagulum of fibrin," in view
of the more probable explanation I have suggested.
Again referring to the figure and adhering to our simile
of bundles of insulated wires, it will be evident that if we
arrange these in a trough and pour melted bitumen around
them the bitumen would form an enveloping sheath,
corresponding, roughly, to the epineurium.
We will take, as another example, the core of a sub-
marine cable. The conductors of which there are usually
eight or more are separated from each other by gutta-
percha, and the total insulation is made up of three layers
of gutta-percha and three layers of Chatterton's compound,
superimposed one upon the other.
As an instance of what is done in practice I will
quote from Herbert's Telegraphy.
In the telegraph system of the
post-office there are, of course, a large
number of telegraph and telephone
circuits, which by reason of their being
in juxtaposition require about the
same measure of protection from
induction as the multifarious fibrillse Fig. 86. SECTION OF
of the sciatic nerve. A Sc * EE * D CA *^-
In order to get rid of inductive interference various
devices, such as twisting the wires, were tried with more
or less success, but the method which has given the best
results is thus described by Mr. Herbert : " The conductor
164 STUDIES IN ELECTRO-PHYSIOLOGY:
is first covered with three wrappings of paper, the
first of which may be either spiral or longitudinal, but the
other two are invariably applied spirally. The spiral
wrappings are applied so as to form a helical air-space
throughout the length of the core. The conductor thus
insulated is then enclosed in a final wrapping of paper,
forming a closed helix without overlap. Over this is laid
a helical winding of copper tape, with an overlap. . . . The
whole of the cores are laid together, and a seamless cylin-
drical sheathing of lead, at a temperature of 600 F., is
applied to the cable."
This description refers, needless to say, to a land cable,
and the paper and air insulation are designed to reduce the
capacity.
" The copper tape forms a continuous conducting tube
around the wire, and as this tube is earth-connected, either
by direct contact with the lead sheathing or indirectly by
the tapes of the other cores, it will be obvious that induction
between the wires cannot occur. Firstly, Faraday's
experiments showed that variations in the differences of
potential existing or produced between conductors within
a metallic covering produce no effect outside that covering.
Secondly, any source of inductive disturbances brought to
bear upon a screened conductor produces the whole of its
effects upon the copper tape. The magnetic lines of force
induce currents along the tape covering the wire, and as this
path is highly conductive, practically the whole of the
energy is absorbed by it. In order to produce an inductive
effect, currents must be generated in the tape of the
disturbing wire and also in the tape of the disturbed wire
before the second conductor is reached."
It is at least a coincidence that in the " flex," the cable
and the nerve, the axis cylinder should be composed of a
bundle of funiculi instead of one wire, and that the insula-
tion should take the form of several layers of a semi-plastic
ANIMAL AND VEGETABLE 165
material. One might, indeed, be tempted to think that
while the physiologist has held the electrician more or less
in contempt, the latter has achieved his object by copying
certain of the natural processes described by the former.
That this is so is, however, open to doubt, because it is
questionable whether at the inception of telegraphy there
was in existence any illustration published of the nervous
system of man which could have so guided or inspired the
electrician. Moreover, it is difficult to believe that were
these systems of insulation borrowed from or suggested by
any physiological work we should have remained in
ignorance of the true functioning of the nervous system for
so long a period of time. The explanation, no doubt, is
that the electrician discovered certain natural laws and,
applying them, unconsciously imitated the work of the
Creator.
TERMINATION OF NERVES IN MUSCLE.
In the voluntary muscles the motor nerve-fibres have
special end-organs called end-plates. In the involuntary
muscles the fibres form complicated plexuses near their
termination. . . . Considerable variation in the shape of
the end-plates occurs in different parts of the animal
kingdom. In the voluntary muscles the fibre branches
two or three times, and each branch goes to a muscular
Fig. 87. (After Schafer.)
fibre. Here the neurilemma becomes continuous with the
sarcolemma, the medullary sheath stops short, and the
axis cylinder branches several times,
166 STUDIES IN ELECTRO-PHYSIOLOGY:
A termination of medullated nerve- fibres in tendon
near the muscular insertion is shown by Golgi (Fig. 87),
but more interesting is Szymonowicz's drawing of end-
plates with the axis cylinders and their final ramifications
of fibrillee, as it also makes it clear that the muscular fibres
vary in diameter and therefore in tension also.
The word " plates " is confusing. They do not look
like plates, but more closely resemble bunches of wire-
The term " end-organs " is in keeping with their appearance
and probable function, and we will so refer to them.
We must not for one moment depart from our hypo-
thesis of the condenser-compartment action of muscular
fibre, nor forget that the contraction of muscle is not along
a straight line but in curves, and, furthermore, that the
sarcomeres of a muscular fibre may not be required to be,
and obviously are not, connected wholly in series.
Suppose these end-organs to be composed of fibrillae,
stretching to and connecting with different sets of sar-
comeres, in such manner that those, and those alone, would
be directly stimulated or acted upon, and we may begin to
comprehend in some measure their function and dis-
tribution.
Professor Rosenthal gives the following account of
the termination of nerve in muscle : " The nerve passes
into direct contact with the muscle-substance. . . . The
nerve-fibres, in their course within the muscle, touch
externally many muscle-fibres, over which they pass before
they finally end at another muscle-fibre . . . only those
pulsate at which the nerve-fibre ends. . . . The nerve-
sheath is, as we already know, a real isolator as regards the
process of excitement within the fibre ; for an excitement
within a nerve-fibre remains isolated in this, and is not
transferred to any neighbouring fibre. It is quite im-
possible, therefore, that it can transfer itself to the
muscle-substance, since it is separated from the latter
ANIMAL AND VEGETABLE
167
not only by the nerve-sheath, but also by the sarco-
lemma.
But if the nerve-fibre penetrates the sarcolemma, and
if nerve-substance and muscle-substance are in immediate
contact, then the transference of the excitement present in
the nerve to the muscle-substance is intelligible."
The plexuses of the involuntary muscles probably form
part of a closed-circuit system designed to maintain
equilibrium. The plexus of Auerbach, as shown in
Halliburton, is, roughly, thus :
Fig. 88. PLEXUS OF AUERBACH.
(After Cadiat.)
Without unduly taxing the imagination one could
conceive that plexus to be a distributing and equalising
station, provided in each of its branches and throughout
its ramifications with condensers of adjusted capacity, so
that at each and every point there would be, in normal
health, a certain given and definite tension. By " equalis-
ing " I mean an automatic " give-and-take " arrange-
ment to neutralise any excess or compensate for any
deficiency.
168 STUDIES IN ELECTRO-PHYSIOLOGY:
DENDRONS AND SYNAPSES
AND THEIR PROBABLE FUNCTION
The grey matter of the cerebellum contains a large
number of small nerve-cells, and one layer of large cells.
These are flask-shaped and are called the cells of Purkinje.
The neck of the flask breaks up into branches, and the axis
cylinder process comes off from the base of the flask.
The whole nervous system consists of nerve- cells and
their branches, supported by neuroglia (epiblastic or
insulating material) in the central nervous system, and
by connective tissue (binding and more or less non-
conductive) in the nerves. Some of the processes of a
nerve-cell break up almost immediately into smaller
branches, ending in arborescences of fine twigs ; these
branches are now called dendrons. One branch becomes the
long axis cylinder of a nerve-fibre, but it also ultimately
terminates in an arborisation ; it is called the axis cylinder
process, or, more briefly, the axon. The term neuron is
applied to the complete nerve-unit, that is, the body of the
cell, and all its branches. The cell processes are said to
contain Nissl's granules, but we have it on the authority
of Dr. Mott that these do not exist, as such, in the living
cell, and probably not therefore in the living dendron
(seep. 190).
Such is a brief physiological description of the dendrons
and the processes associated with them, and from it there
does not at first sight appear to be any intimate connection
between them and the synapses. If, however, they are
considered in the light of Cajal's illustration of the synaptic
connections of sympathetic cells from the superior cervical
ganglion of man, as given by Schafer (see Fig. 90), it
will be seen that the evidence points to the dendrons being
branch-circuits, the arborisations having the function of
condensers, or Leyden jars ; each synaptic junction or
ANIMAL AND VEGETABLE 169
dielectric process offering resistance, and therefore inter-
posing delay to the passage of the current or impulse.
Halliburton has told us, and it is an important fact
to remember, that each nerve-unit is anatomically inde-
pendent of every other nerve-unit. The arborisations
interlace and intermingle, and nerve impulses are trans-
mitted from one nerve-unit to another, through contiguous,
but not through continuous structures. Furthermore it is
open to question whether a so-called continuous current
of electricity is continuous in the strictest sense of the
word, or whether it is really a series of polarisations and
discharges occurring with such velocity as to appear to be
continuous.
Put shortly, the views taken of the propagation of
electric force by molecular action consider the molecules of
the interpolar wire to be as follows :
trc
Fig. 89.
c being the copper and z the zinc end, the shaded parts
being 4- and the unshaded . The first effect of the
electric force developed by the chemical affinity of the
zinc for the O or SO 4 is to throw all the molecules of the
circuit into a polar condition, the force being transmitted
from molecule to molecule in both directions. Positive and
negative electricities appear in each molecule of the
circuit ; and if the action be powerful enough, discharge
takes place throughout the whole, each molecule giving out
its electricities to those next it, which, throwing out the
opposite electricities, produce electric quiescence through-
out. A constant series of such polarisations and dis-
charges, taking place with enormous rapidity, constitute
a current.
In the body the impulse may be, and probably is,
170 STUDIES IN ELECTRO-PHYSIOLOGY:
induced in and not transmitted through a contiguous
structure, in tjie same manner that a current passing along
one insulated wire may induce a current in another,
contiguous but not continuous, insulated wire ; of opposite
sign understood.
The following is a sketch from the drawing I have
mentioned :
Fig. 90. (After Cajal.)
Synaptic connections of a sympathetic cell from the superior cervical
ganglion of man.
A = cell with well-marked intracapsular dendrons ; C, D = synapses
between dendrons outside the cell capsules ; a = axon ; 6, d, c, e = extra-
capsular dendrons.
Let us assume that the cell A is the source or container
of energy and that D is a typical synapse ; I say D because
its structure is more clearly marked than that of C.
Fig. 91.
Let the dark lines, c, c, c, represent conductors ; d, d, d, non-conductors,
and e, e, connective tissue.
ANIMAL AND VEGETABLE 171
Furthermore, we will draw D upon a larger scale, as I
imagine it to be (see Fig. 91).
We can have no doubt that c, c, c are conductors
because they transmit impulses ; d, d, d must be dielec-
trical in character, as they are designed to conserve energy
in the axon, and there is reason for the belief that both
neuroglia and connective tissue are non-conducting sub-
stances.
A condenser, as used in telegraphy, is conventionally
shown in illustration, and the
analogy, if we pursue it, is ~ ^j- *-
rather remarkable. In the
rig. wlA.
figure only the conduct-
ing plates are shown. Let us insert the dielectric, and
the sy nap tic connection appears to be a condenser of large
surface-area, but possibly, by reason of the points or pro-
jections, of comparatively high tension.
Fig. 92.
According to Schafer, the " arborisations from different
cells may interlace with one another (as in the olfactory
glomeruli, in the retina, and in the sympathetic ganglia),
or a terminal arborisation from one cell may embrace the
body or the cell-processes of another cell ; as with the cells
of the spinal cord and the cells of the trapezoid nucleus of
the pons Varolii, and in many other places. The term
neuro-synapse may be applied to these modes of junction.
By them nerve-cells are linked together into long chains
of neurons, the physiological path being uninterrupted,
although the anatomical path is believed to be interrupted
at the synapses. "
172 STUDIES IN ELECTRO-PHYSIOLOGY:
From this it would appear that the two arborisations as
shown in the enlarged sketch of D (Fig. 91) may actually
touch or embrace each other, so that no additional resistance
may be offered by intervening connective tissue, but even
in such case there .would be two thicknesses of dielectric
(d, d) to one of conductor (c) in the path of the impulse,
and the result must be delay during the accumulation of
tension at the arborisation nearest the cell, the plates being
further apart.
As the cell is in the superior cervical region two things
follow, logically: i.e. (I) the impulse from it is efferent,
and (2) the tension in the dendron is comparatively high.
We know also that electricity concentrates upon points or
projections, and the arborisations appear to be constructed
in accordance with this law.
When we are able to examine the structure of the
brain, I think the evidence in support of the human organism
being neuro- electrically controlled with consequent
chemical action will be even more convincing than that
I have already adduced.
One thing stands out prominently and it cannot be
given too great prominence this vital action, neuro-
electrical or chemical, or both, cannot go on unimpaired if
the natural insulation resistance, in any part of the body, is
broken down or interfered with.
CONNECTION OF MUSCLES AND BONES, ETC.
If, in addition to a consideration of the different
behaviour of muscular tissue owing to differences of tension*
quantity, and resistance, we unite a brief survey of their
connection with bones, we may obtain a still better grasp of
the subject. As a considerable number of muscle-fibres
constitute the trunk of the muscle, strong slender threads
of the nature of connective tissue unite into cords which
ANIMAL AND VEGETABLE
are called the muscle-tendons. They are sometimes short*
sometimes long, thicker or thinner according to the size of
the muscle, and they serve to attach the muscles firmly to
the bones, to which, acting like ropes, they transmit the
tension of the muscles. One of the two bones to which a
muscle is attached is usually less mobile than the other,
so that when the muscle shortens, the latter is drawn down
against the former. In such a case the point of attachment
of the muscle to the less mobile bone is called its origin,
while the point to which it is fixed on the more mobile bone
is called its attachment (epiphysis). For instance, there
is a muscle which, originating from the shoulder-blade and
collar-bone, is attached to the upper arm-bone ; when this
muscle is shortened the arm is raised from its perpendicular
pendant position into a horizontal position. A muscle is
not always extended between two contiguous bones.
Occasionally passing over one bone, it attaches itself to the
next. This is the case with several muscles which, origin-
ating from the pelvic bone, pass across the upper thigh-bone
and attach themselves to the lower thigh-bone. In such
cases the muscle is capable of two different movements :
it can either stretch the knee, previously bent, so that the
upper and the lower thigh-bones are in a straight line, or
it can raise the whole extended leg yet higher and bring it
nearer to the pelvis. But the points of origin and of
attachment of muscles may exchange offices. When both
legs stand firmly on the ground the above-mentioned
muscles are unable to raise the thigh ; instead, on shorten-
ing, they draw down the pelvis, which now presents the
more mobile point, and thus bend forward the whole
upper part of the body. ... In a previous examination
of the action of muscle we have dealt with an imaginary
muscle, the fibres of which were of equal length and par-
allel to each other. Such muscles do really exist, but they
are rare. When such a muscle shortens, each of its fibres
174 STUDIES IN ELECTRO-PHYSIOLOGY:
acts exactly as do all the others, and the whole action of
the muscle is simply the sum of the separate actions of all
the fibres. As a rule, however, the structure of muscles is
not so simple. According to the form and the arrange-
ment of the fibres, anatomists distinguish short, long, and
flat muscles. The last mentioned generally exhibit devia-
tions from the ordinary parallel arrangement of the fibres.
Either the fibres proceed at one end from a broad tendon,
and are directed towards one point from which a short
round tendon then effects their attachment to the bones
(fan-shaped muscles), or the fibres are attached at an angle
to a long tendon, from which they all branch off in one
direction (semi-pennate muscles), or in two directions like
the plumes of a feather (pennate muscles). In the radiate
or fan-shaped muscles the pull of the separate parts takes
effect in different directions. Each of these parts may act
separately, or all may work together ; and in the latter case
they combine their forces, as is invariably the case with
forces acting in different directions, in accordance with the
so-called parallelogram of forces. As an example of this
sort of muscle the elevator of the upper arm (the deltoid
muscle) may be examined. Contractions of the separate
parts really occur in this. When only the front section of
the muscle contracts, the arm is raised and advanced in
the shoulder-socket ; when only the posterior part of the
muscle contracts, the arm is raised backward. When,
however, all the fibres of the muscle act in unison, the
action of all the separable forces of tension constitutes a
diagonal which results in the lifting of the arm in the plane
of its usual position.
" In some semi-pennate and pennate muscles the line of
union of the two points of attachment does not coincide
with the direction of the fibres. When the muscle contracts
each fibre exerts a force of tension in the direction of its
contraction. All these numerous forces, however, produce
ANIMAL AND VEGETABLE 175
a single force which acts in the direction in which the
movement is really accomplished, and the whole action of
the muscle is the sum of these separate components, each
derived from a single fibre. In order to calculate the force
which one of these muscles can exert, as well as the height
of elevation proper to it, it would be necessary to determine
the number of the fibres, the angle which each of these
makes, with the direction finally taken by the compound
action, as well as the length of the fibres these not being
always equal. . . . The direction in which the action takes
effect does not, however, depend only on the structure of
the muscle, but chiefly on the nature of its attachment to
the bone. Owing to the form of the bones and their
sockets, the points of connection by which the bones are
held together, the bones are capable of moving only within
certain limits, and usually only in certain directions. For
instance, let us watch a true hinge-socket, such as that of
the elbow, which is capable only of bending and stretching.
As, in this case, the nature of the socket is such that motion
is only possible in one plane, the muscles which do not lie
in this plane can only bring into action a portion of their
power of tension, and this may be found if the tension
exercised by the muscle is analysed in accordance with the
law of the parallelogram of forces, so as to find such of the
component forces as lie within the plane." (Rosenthal, 1895.)
Here it may be useful to give a brief description of what
is meant by the parallelogram of forces, my authority
being Dr. M'Gregor-Robertson.
Let O, in the figure on next page, be a particle under the
influence of two forces, one, OB, urging it in the direction
of B, and the other, OA, urging it in the direction of A.
It is evident that the particle cannot proceed along either
path, but will choose a path which is a compromise between
the two. It will move upwards. Let a third force,
represented by the weight, be applied to O, and let this
176 STUDIES IN ELECTRO-PHYSIOLOGY:
third force be adjusted so that O remains in its original
position, and suppose the weight to represent a force of
1 Ib. Then O is under the influence of three forces ; but it
Fig. 93.
is at rest, so that the forces are in equilibrium. The forces
OA and OB are both tending to draw O upwards, and they
are completely counterbalanced by the 1 Ib. weight. To
put it another way, the weight is tending to pull O down-
wards, but is counterbalanced by OA and OB. But the
weight would be counterbalanced exactly by a force of
1 Ib. acting in the direction directly opposed to it, that is,
in the direction of the straight line drawn up from O. If,
therefore, OA and OB be withdrawn, and one force sub-
stituted equal to the weight opposing them, equilibrium
will still be maintained. So the two forces OA and OB
can be replaced by a single force, which is called the resultant
force. If a parallelogram be constructed on OB, OA, as
indicated in the following figure, it will be seen that the
Fig. 94.
resultant force is the diagonal of the parallelogram. The
two forces OA, OB, are acting on a particle. To find the
ANIMAL AND VEGETABLE 177
direction in which the particle will move, a parallelogram is
constructed of which OA and OB form two sides, and then
the diagonal OR of the parallelogram is drawn. It gives
the direction which the particle takes ; it is the resultant of
the two forces OA, OB ; and if the lines OA and OB repre-
sent by their lengths the magnitude of the forces, then the
diagonal will represent by its length the magnitude of the
resultant force. This is the parallelogram of force.
In a similar way one force may be made to take the
place of several forces. Let a parallelogram be constructed
on the lines representing two of the forces. Take the
diagonal, and with it and the line representing the third
force construct another parallelogram. Its diagonal is
the resultant of the three forces ; with it and the line
representing the fourth force, the resultant of four forces
may be found, and so on.
" It is different in the case of the more free ball-sockets,
which permit movement of the bone in any direction
within certain limits. When a socket of this sort is sur-
rounded by many muscles, each of the latter, if it acts alone>
sets the bone in motion in the direction of its own action.
If two or more of the muscles assume a state of activity at
the same time, then the action will be the resultant of the
separate tensions of each.
" There is yet another way in which the work performed
by the muscles is conditioned by their attachment to the
bones. The latter must be regarded as levers which turn
on axes, afforded by the sockets. They usually represent
one-armed, but sometimes two-armed levers. Now, the
direction of the tension of the muscles is seldom at right
angles to that of the movable bone lever, but is usually at
an acute angle. In this case, again, the whole tension of
the muscle does not take effect, but only a component,
which is at right angles to the arm of the lever. Now, it is
noticeable that in many cases the bones have projections
N
178 STUDIES IN ELECTRO-PHYSIOLOGY:
or protrusions at the point of attachment of the muscles,
over which the tendon passes, as over a reel, thus grasping
the bone at a favourable angle ; or, in other cases, it is
found that cartilaginous or bony thickenings exist in the
tendon itself (so-called sesamoid bones), which act in the
same way. The largest of these sesamoid bones is that in
the knee, which, inserted in the powerful tendon of the
front muscle of the upper thigh, gives a more favourable
direction to the attachment of this tendon than there
would otherwise be." (Rosenthal.)
I have quoted at considerable length from Professor
Rosenthal, but his explanation of the connection of muscles
with bones is so lucidly given, that while I may be in need
of his forgiveness I owe no apology to my readers for the
digression. The measure of my offence is, however, not
ended. So far we have been dealing with voluntary
muscle. It now remains to examine plain muscle in respect
of which physiological works in general are comparatively
silent. We are told that they are longitudinally but not
transversely striated, and I cannot reconcile this with
<c shortening and broadening " due to the electrical law of
attraction and repulsion. This, however, we will consider
in its proper place.
RESPONSE OF HUMAN MUSCLES AND NERVES
TO ELECTRICAL STIMULATION
As this has an important bearing upon the theoretical
explanation I have so far given of the electro-physiology
of the motor apparatus, it may be permissible to quote
and comment upon Halliburton. He says : " When the
nutrition of the nerves is impaired much stronger currents
of both the induced and constant kinds are necessary to
evoke muscular contractions than in the normal state."
If for " nutrition " we read " conductivity " comment
is unnecessary.
ANIMAL AND VEGETABLE 179
" When the nerves are completely degenerated (as, for
instance, when they are cut off from the spinal cord, or
when the cells in the cord from which they originate are
themselves degenerated, as in infantile paralysis), no
muscular contraction can be obtained on stimulating the
nerves, even with the strongest currents."
Obviously, there is a complete loss of conductivity.
In the old days the cables laid in South American waters
were insulated with india-rubber. The sulphur in the
rubber caused rapid degeneration of the conductors, and
the application of 1,000,000 volts at A would not cause a
receiving instrument at B to contract, by reason of a break
or breaks of continuity.
" The changes in the excitability of the muscles are less
simple, because in them there are two excitable structures,
the terminations of the nerves (end-organs) and the mus-
cular fibres themselves."
It is open to question whether the end-organs are not
inducing bodies. Nowhere do they appear to make actual
contact ; that is to say, they do not connect as wires are
connected so that a direct current flows through them, but
appear to act inductively upon the organs they influence.
" Its excitability " (that of muscle) " corresponds in
degree to that of the nerve supplying it."
In accordance with Ohm's law the degree of excitability
of the muscle would be governed by the resistance of the
motor nerve supplying it.
" The fact that, under normal circumstances, the con-
traction which is caused by the constant current is as quick
as that produced by an induction shock, is ground for
believing that in health the constant, like the induced
current, causes the muscle to contract chiefly by exciting
the motor nerves within it."
Tensions being equal, the effect of an induction shock
is not, cannot be, the same as the effect produced upon
180 STUDIES IN ELECTRO-PHYSIOLOGY:
muscle by an impulse originating in a constant or direct
current of normal potential. In both cases the motor
nerves convey the impulse or impulses to muscular fibres,
but the muscular response cannot, in my judgment, be
identical.
" When the motor nerve is degenerated, and will not
respond to any form of electrical stimulation, the muscle
loses all its power of response to induction shocks. The
nerve-degeneration is accompanied by their rapid wasting,
and any power of response to f aradism they possessed in the
normal state is lost."
That naturally follows.
" But the response of the muscle to the constant
current remains, and is, indeed, more ready than in health."
The meaning here is somewhat obscure. If it is sought
to convey the constant current to the muscle by means of
the degenerated motor nerve, and there is a complete break
of continuity, no current could pass and no response be
given. If, however, the sarcomeres are stimulated directly
the normal resistance of the motor nerve would be elimi-
nated and the muscle should certainly give a readier
response. This may be what is meant, because we have
been told that " when the motor nerve is degenerated and
will not respond to any form of electrical stimulus the muscle
loses all its power of response to induction shocks." But
the phenomenon may be due to the end-organs, as well as
the motor nerve-fibres, transforming or modifying in
normal health an induction shock a momentary impulse
so that the muscle could respond to it, and that after
degeneration no such modification could occur.
" Suppose a patient comes before one with muscular
paralysis. This may be due to disease of the nerves, of the
cells of the spinal cord, or of the brain. If the paralysis is
due to brain disease, the muscles will be slightly wasted
owing to disuse, but the electrical irritability of the
ANIMAL AND VEGETABLE 181
muscles and nerves will be normal, as they are still in
connection with the nerve cells of the spinal cord which
control their nutrition."
True. But where does the impulse originate, nor-
mally ? In a nerve cell or cells in the motor area of the
brain. If that cell or those cells fail to act, no impulse can
pass from brain to muscle. In other words, the rest of
the apparatus is in working order, but some of the battery
cells have given out.
" But if the paralysis is due to disease either of the
spinal cord or of the nerves, this nutritive influence can no
longer be exercised over the nerves or muscles."
Of course not. There is a partial or total loss of
conductivity by reason of the influence of disease upon the
spinal cord or the nerves. The motor apparatus generally
may be in working condition, but no energy can be con-
veyed to it, and it cannot, therefore, be set in motion.
182 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER XII
CARDIAC MUSCLE
THE problem of the structure and precise function-
ing of cardiac muscle is not easy of solution, owing, in
the main, to the absence of diagrams illustrating its
connections. Several facts, however, stand out promin-
ently.
It is said (1) to be intermediate in structure ^and
properties between voluntary and involuntary muscle ;
(2) to contract more slowly than ordinary striped muscle ;
(8) to be striated ; and (4) to have no true sarcolemma,
44 although there is a thin superficial layer of non-fibrillated
substance." (Schafer.)
Considering, as we must do, each segment as a sarco-
mere, it will be seen that the segments differ in length and
in diameter (permitting of infinite variation of tension) ;
that some are non-nucleated, and that there are branch, or
shunt, circuits which no doubt play their part in the
inductive regulation of tension in an automatic neuro-
electrical system, because, although the heart's action
may be subject to psychological influences, it must
be supplied, from within or without, with energy un-
intermittently, and therefore must form part of an
automatic system.
And here, perhaps, we may begin to appreciate the
beautiful regulation exercised by the vagus nerves. The
energy, partly self-contained or not, which, in life, is
ANIMAL AND VEGETABLE 183
constantly supplied to the heart,is by way of the sympathetic,
while the vagus nerves are inhibitory, or, in other words,
exert a governing or opposing electromotive force. They
are buffers, or springs, regulating the flow of energy to the
heart, much in the same way that a rise or fall of tempera-
ture may regulate the fall or rise of a gas-flame in a heating
apparatus.
We learn, from physiological research, that man inhales
400 c.c. of oxygen per minute during the daytime and
200 c.c. per minute during the night. I know, from my
own work, that if the hand-to-hand galvanometric deflec-
tion of a normally healthy man during the daytime is
350 mm. it will fall at night to about 175 mm.
That means there is a falling off in the production or
reception of nervous energy of fifty per cent.
But the controlling, governing current from the brain
the inhibiting current is also halved, because generation,
or reception, is halved, and therefore there is no alteration
in equilibrium, and the heart must receive a proportionate
supply of energy at all times, supposing there to be no
escape of nerve-current or excitement of the vagi. Should
such an escape occur, the result, or one result, should be
higher blood-pressure, while in the event of anything, such
as cold or some toxin, increasing the resistance of the
conducting substance of the vagi, the same phenomenon
should bepresented,because inhibition would be diminished.
On the other hand, any cerebral disturbance tending to
unduly stimulate the cardiac branches of the vagi would
have the effect of slowing the heart down, possibly in
extreme cases to a fatal extent.
The main differences, so far as I can see, between
voluntary and cardiac muscles are : (1) the first are supplied
by open circuits through which impulses are sent from the
brain ; (2) cardiac muscles form part of a closed circuit
or circuits regulated by cell-groups possibly other than
184 STUDIES IN ELECTRO-PHYSIOLOGY:
unipolar ; (3) voluntary muscles contract in parcels of
sarcomeres and not necessarily in one direction ; and (4)
cardiac muscles contract in" walls, "rhythmically, and as
the rate of propagation of the wave is slower than in
voluntary muscles, their inductive capacity, and possibly
their resistance, must be greater, probably by reason of the
conducting surfaces being connected, mainly if not en-
tirely, in parallel (see also p. 94).
PLAIN MUSCLE
In regard to plain muscle there is, as I have remarked
elsewhere, a lack of information. To my mind there can
be no manner of doubt that they are transversely striated,
although the striae are too small to be clearly observed.
I am forced to this conclusion by
several considerations, one of which
is that it is difficult to conceive how
they can shorten and broaden if only
longitudinally striated. They would
flatten but not shorten. Professor
Rosenthal says : " It must be observed
that the distinction between striated
and smooth muscle-fibres is not abso-
lute ; for there are transitionary forms,
such as the muscles of molluscs. The
latter consist of fibres, exhibiting to
some extent a striated character, and,
in addition to this, the character of
Fig. 05. MUSCULAR double refraction. At these points
FIBRE-CELT. FROM THE the disdiaclasts are probably arranged
MUSCULAR COAT OF
THE SMALL INTESTINE, regularly and in large groups, while at
(After Schafer.) ^^ points ( as in true smoo th muscle-
fibres) they are irregularly scattered and are therefore not
noticeable."
ANIMAL AND VEGETABLE 185
Nor does Schafer really commit himself definitely to
the statement that plain muscle is not transversely striated.
He says : " Plain muscular tissue is composed of long,
somewhat flattened, fusiform cells which vary much in
length.
" Each cell has an oval or rod-shaped nucleus, which
shows the usual intra-nuclear network, and commonly one
or two nucleoli. The cell -substance is finely fibrillated,
but does not exhibit cross-striae like those of voluntary muscle
There appears, as in cardiac muscle, to be a delicate non-
striated external layer, probably a stratum of undifferen-
tiated protoplasm, certainly not a true sarcolemma. . . .
There is a little intercellular substance which is bridged
across by filaments passing from cell to cell. Some
authorities, however, deny that the involuntary cells are
thus connected, and hold that the appearance of bridging
fibres is due to intercellular connective tissue. It is,
however, difficult to understand how the contractions are
propagated from cell to cell if there is no sort of continuity
between the cells." *
Now, in regard to the speculative explanation I am
about to give, it is very necessary to remember that this
tissue responds but slowly to a stimulus, and that the
contraction spreads as a wave from fibre to fibre. If we
depart from the theory of condenser-action the problem
must, so far as I am concerned, remain without attempt at
solution, but if we adhere to it we may begin to see day-
light.
These fibres of involuntary muscle are, admittedly*
longitudinally striated. They, however, contract and
become shorter and broader. It is quite evident tha*
with condenser-action and longitudinal striation only they
would merely flatten (Figs. 96; 97) :
* The italics are mine.
186 STUDIES IN ELECTRO-PHYSIOLOGY:
Fig. 06.
Before contraction.
Fig. 97.
During contraction.
whereas, I take it, what really happens is this, roughly :
Fig. 98.
Before contraction.
Fig. 99.
During contraction.
For this to occur it is not at all necessary for the fibres
to be transversely striated as voluntary muscle is striated.
All that is required is that they should possess something
of the nature of an elastic sarcolemma and the external
ANIMAL AND VEGETABLE
187
layer must be elastic to permit contraction and that
they should be bridged at intervals by some non-conducting
substance, possibly connective tissue. Condenser-action
would then take place as in voluntary tissue, and the rate
of propagation of the impulse would be governed by the
considerations set forth in the chapter upon Inductive
Capacity.
In this manner we can perceive how the contraction
spreads as a wave from fibre to fibre, and why it is that the
cells vary much in length. They also, no doubt, vary much
in diameter in order to enable the tension to be varied,
but there is this essential difference, I think, between
voluntary and plain muscle : the former is required to
contract in curves, at different velocities in the course of
those curves and not in the same direction throughout,
while the function of the latter is merely to shorten.
If that is so a less complicated form of fibre would serve
the purpose, nor would the complex end-organ connec-
tions be necessary. We cannot compare the cells, for
reasons I have given, to a chain of condensers in series,
i.e. s*"* 1 1 j | 1 1 1 [ "* , but must imagine them
to be connected in parallel or series-parallel. Nor is
this opinion without warrant, as the following figure goes
to show :
Fig. 100. MUSCLE-CELLS OF INTESTINE (SZYMONOWICZ), MAGNIFIED
530 DIAMETERS. (After SchAfer.)
188 STUDIES IN ELECTRO-PHYSIOLOGY:
" The fully-formed muscle retains its syncytial char-
acter, and is not formed by completely separated cells.'*
(Schafer.)
In conclusion, my considered opinion is that while
plain muscle is not transversely striated in the sense that
voluntary muscle is transversely striated, the longitudinal
fibres are bridged across by some non-conducting substance?
and that the chief difference in the structure of the two is
the absence in the former of the sarcous element. As,
however, the charge, instead of being neutralised at
various points, passes as a wave from cell to cell, the
sarcous element can naturally be dispensed with.
ANIMAL AND VEGETABLE 189
CHAPTER XIII
NISSL'S GRANULES
THAT many of the nerve cells, if not all of them, contain
organically combined iron, as suggested by Macallum, I do
not doubt, but the weak link which has hitherto existed
in my chain of reasoning has been the manner in which
Nissl's granules so-called have been shown, in physio-
logical and histological works, to be distributed in the cell
contents.
As will be seen from Figs. 109, 110 (taken from Schafer)*
they appear as masses, and this is not quite consistent
with the theory that neuro-electricity is generated by the
association of iron with oxygen in the protoplasm. One
would expect to find iron in the form of minute particles
arranged in the cell contents in a well-defined manner ;
a manner which, if it could be seen with a sufficiently high
power, would make it clear how electrical attraction and
repulsion as well as generation are brought about. In
health not only does the nucleus occupy a central position
in the cell, but the nucleolus is more or less centrally
situated in the nucleus, and this phenomenon, as well as
that of amoeboid movement, would seem to have its origin
in electrical activities and to be in accordance with the
experiments of Ampere.
With iron in the shape of irregular masses it is difficult
to see how this harmonious result is arrived at, no matter
how convinced we may be that it is so.
The illustrations to which jl have referred were based
100 STUDIES IN ELECTRO-PHYSIOLOGY:
upon experiments with dead cells, and I have always
contended that the difference between the living and the
non-living is so great as to render results with the latter
not only almost nugatory but often misleading.'
The valuable work of Dr. Mott, however, has thrown
new light upon the subject and helped to make clear that
which was previously obscure. He has found that the
basophile staining substance which forms the Nissl granules
does not exist as such in the living cells, but is the result
of coagulation. " If living cells are examined micro-
scopically with dark-ground illumination they are seen to
be filled with small granules or globules, each of which,
after escaping from the cell, remains discrete.
Fig. 101. DRAWING OF AN" ANTERIOR HORN CELL, WITH PROCESSES.
(After Mott.)
" They are refractile," says Mott, " and appear white
and luminous ; this is due to a delicate covering film of a
lipoid substance which encloses a colloidal fluid, probably
consisting of a solution of salts and cell globulins. When
the cell dies this colloidal fluid is massed together in little
blocks the Nissl granules ; the intervening denser colloidal
substance is continuous with the colloidal substance of
the axon and dendrons. ... It thus appears possible that
these granules represent a large oxygen surface, like
spongy platinum, within the cell. When the cells die, the
lipoidal film of the globulin containing fluid is destroyed,
coagulation occurs, and the Nissl granules are formed.
These facts accord with the knowledge that stimulation of
ANIMAL AND VEGETABLE 191
a piece of nerve causes practically no metabolic change or
using up of oxygen, therefore the mere conduction of a
stimulus along a nerve does not entail loss of neuro-
potential. The chemical processes incidental to the
using up of nervous energy in the neuron take place in the
cell itself, and it is for this reason that the blood supply of
the grey matter is six times that of the white matter."-
All this, coming as it does from a great pathologist, is
strongly in favour of the opinions I hold.
192 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER XIV
THE NODES OF RANVIER
IN these the axis -cylinder is invariably shown as passing
in an uninterrupted course through the node, but although
it is highly speculative and daring to say so, I doubt
whether this is the case functionally, although we must
believe it to be so anatomically. The following illustration
is a typical one :
Fig. 102. MEDULLATED NERVE-FIBRE SHOWING FIBRILS OF Axis
CYLINDER (BETHE). The fibrils are seen passing, without interruption,
across a node of Ranvier. (After G. N. Stewart.)
Now, these nodes occur at regular and innumerable
intervals along the course of an axis-cylinder, but their
function appears, so far as my reading goes, to be im-
perfectly understood. If, unlike their prototypes in the
bamboo and the sugar-cane, the axis-cylinder is struc-
turally continuous throughout its course, they do not seem
to serve any useful purpose. If, on the other hand, there is
a species of synapse at each node, their purpose and function
ANIMAL [AND VEGETABLE 198
become at once apparent, for they would afford protection
to the axon against extensive degeneration consequent
upon injury.
Let us examine a node in a piece of bamboo.
According to Strasburger there is a
wax incrustation, in the form of small
rods, at a, b. The interior of the stem,
between the nodes, is filled with a soft
sponge-like substance which, while the
plant is alive, transmits electricity each
internode indeed seems to bear some
resemblance to a cell so that the line
a, b, notwithstanding the wax incrusta-
tion, does not involve a break of Fig 103
continuity. That being so, it would
appear that the node is of the nature of a synapse,
and that if the current is not inductively transmitted
there is considerable added resistance at each node.
These nodes, be it remarked, occur at regular intervals
upon the stems of bamboo (all canes) and sugar-cane, in
much the same way as they do along the course of human
nerves.
In the nodes of Ranvier the line a, b is absent, and it
does not necessarily follow because a colouring matter like
picro-carmine diffuses into the fibre only at the nodes, and
stains the axis-cylinder red, while it does not diffuse
through the white substance of Schwann, that there is any
difference in the substance of the axon itself at those
points.
But that there is a phase in the nature of a com-
paratively high resistance across the line a, b is, I think,
more than probable ; for this reason :
When a nerve is severed, degeneration in the proximal
segment takes place only as far as the first node of Ranvier.
Consider what, from an electrical point of view, that
o
194 STUDIES IN ELECTRO-PHYSIOLOGY:
may mean. Let us take two nerves, a motor and a
sensory, and see what would happen if they were both
severed in life.
In the case of the motor nerve the battery is in the
brain with one pole to earth (air), while the nerve the
wire, as it were is also to earth through tissue and skin.
The effect of the cut is to remove
the conductor, qud conductor, below
the node immediately above the cut
and to an imaginary line a, b (Fig. 104).
The whole of the apparatus above
the line a, b would be structurally and
electrically intact, and the line a, b,
if of high resistance, would be equiva-
lent, in hydrostatic parlance, to a
ligature applied to an artery or a vein.
Precedent to repair or regeneration
of the lower portion, no muscle below
the cut could receive an impulse.
If, however, the axis-cylinder were
continuous through the node there would be a path of
low resistance at the node an escape of current into wet
tissue and the muscles above the cut could only receive
stimuli at a greatly lowered pressure.
In a sensory path the need of a synaptic node is even
greater, for the sensory nerves are closed circuits, and they
have many ramifications in motor as well as other sensory
paths over which they transmit impulses in various
directions. To take a simple sensory path, however, from,
say, skin to post -spinal ganglion.
Here we have a charged wire, a unipolar guard-cell or
cells to maintain normal potential in that wire, and a
receiving instrument in the cord. If the nerve were severed
no impulse could be conveyed, but, given the line of
resistance a, b, the upper part of the nerve from the first
ANIMAL AND VEGETABLE 195
node above the cut, together with the unipolar cells and
receiving instrument, would be in working order, and only
that portion of skin in connection with the lower part of
the nerve thrown out of gear. If, however, there were no
line of resistance at the node above the cut, all the circuits
with which the nerve is functionally associated would
suffer, the nerve and the cells lose their charge, and the
receiving instrument would be left idle.
It is inconceivable, to my mind, that the resistance of
the axis-cylinder is not greater, much greater, at the nodes
than in the internodes, but as a matter of possibility this,
instead of involving a change of material, may be created
by constriction of the axon, as the effect of constriction in
the course of a liquid conductor is to materially lower
conduction at that point.
In some works the nodes are called u constrictions,*'
and the suggestion is made that instead of the constriction
being due to a tightening of the sarcolemma it is effected
by a band (band of Ranvier) which compresses the axon.
How this may be I do not know, but I am convinced that
in whatever manner it is brought about there is con-
denser-action or similar cause of delay at every node.
196 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER XV
GANGLION CELLS
I HAVE stated elsewhere * that from an electrical point
of view some ganglion cells are condensers and some
storage cells, but this statement calls for elaboration. In
telegraphy and the brain, it is necessary to remember,
both sends and receives messages one of the functions of a
condenser is to maintain electrical equilibrium, and, when
required, to change the sign of current ; whereas the
function of a storage cell is to receive a charge and to hold
it until some disturbance of neuro- electrical equilibrium
calls for its delivery, either wholly or in part. In this
connection let us consider ganglion cells with a view to
attempting to differentiate the condenser pure and simple
from the storage cell.
Condenser-ganglion cells should be studied more
especially in relation to the sympathetic system, the nodes
of Ranvier and the structure of the muscles, bearing in
mind not only the change of sign, i.e., from downward to
upward current, or from efferent to afferent, but control
of regularity of supply. Assuming there to be, for instance,
a flow of nerve-energy of a certain potential from the brain
(downwards) along, say, the sympathetic, the current
strength would vary with the resistances in circuit in
obedience to established laws, but it might be necessary to
regulate both current strength and sign at different points
of the circuit. Without condenser -action the current
would have to reach a junction and return by a nerve- wire,
* Electro-Pathology and Therapeutics.
ANIMAL AND VEGETABLE
197
to change the sign from efferent to afferent, but that change
could be more rapidly if not more effectively made if a
condenser-ganglion cell of the proper capacity were inserted
in position.
Let us assume that we had a downward or efferent
current from the brain along the sympathetic and the
argument is not affected if we suppose an upward or
afferent current to the brain and it was required to take
off at various points an upward current of varying strength.
It might easily be done.
In the following diagram the thick vertical line is
intended to represent the chain of the sympathetic
E thro' high
t +
rent
1
IT! , Condenser
tfivlnjf tzffere.
impulse
Ettiro. '&th resistance
Fig. 105.
Except where a condenser is inserted the impulse from
the brain would be efferent, and its current strength would
198 STUDIES IN ELECTRO-PHYSIOLOGY:
be subject only to Ohm's law, and the tension to the laws
we have been discussing. If at any point it was desired
to alter the sign again or to alter the tension, the insertion of
another condenser-ganglion cell of the required plate-area
in circuit would do it.
The diagrams on next page, Figs. 106, 107, illustrating
the neurons of the motor path (after Halliburton), and
a similar electrical arrangement, will further explain my
meaning.
Study of the physiological diagram will show that,
conforming as the body must do in its structure to estab-
lished electrical laws, the source of energy, i.e., the cell of
the cerebral grey matter, is to earth (in this case air) in
the same manner as the battery in the electrical diagram,
while every muscular fibre is to earth (air) through the
skin. If it is desired to make a large low-tension motor-
cell multipolar, and to transform the tension therefrom
upwards, it is only necessary to provide it with one, or
more, additional arborisation, linking by induction with
one or more condensers of the type of b.
Judging by their effects, we might believe that quantity
and tension constitute two very different elements. They
are in reality but two forms of the same thing. The
transformation of quantity into tension results simply
from the mode of distribution of the same energy. We
realise the transformation by concentrating the energy
within a very small space, which amounts to raising its
level above that of the zero of energy. The converse
operation will transform, on the contrary, tension into
quantity. A coulomb spread over a sphere of 10,000
kilometres radius will give only a pressure of one volt.
Let us spread the same quantity of electricity over a sphere
of a diameter 100,000 times less that is to say, of 100
metres and this same quantity of electricity will produce
a potential a hundred thousand times higher that is to
ANIMAL AND VEGETABLE
199
Electrical. S
fee
J1CC
S^" A
\ 8e$U
Fig. 106.J (4/ter Halliburton.) Fig. 107.
i'CC = small cells at the base of
the posterior cornu.
ACC = large motor-cells of the
anterior cornu.
M = muscular fibres.
PF = axon.
CC = cell of the cerebral grey
matter.
aa low-tension condensers.
bbb = high-tension condensers
200 STUDIES IN ELECTRO -PH YSIOLOG Y :
say, a pressure of 100,000 volts. The quantity of energy
expended has not been varied, only its distribution altered.
(Le Bon.)
In this light we may ponder several forms of spinal
ganglion cells, showing the cell bodies, the afferent sensory
nerves, and the dorsal roots.
Fig. 108.
(After Landois and Stirling.)
To my mind a, c are nerves carrying storage cells,
which would hold their charge unless and until excessive
mental or physical exertion had disturbed neuro- electrical
equilibrium in the sense of bringing about a subnormal
local or general body potential, while b and e are simple
closed circuits, and d a nerve carrying a condenser. Per-
haps this view may throw some further light upon the
subject and help us to a better appreciation of the functions
of ganglion cells. It must be remembered, however, that
the due functionment of both ganglion storage and
ganglion-condenser cells is absolutely dependent upon the
maintenance of their normal insulation resistance. Should
the absolute insulation of the storage cell be broken down
ANIMAL AND VEGETABLE 201
to any extent there would be defective storage, and if the
resistance of the insulating membrane in the condensing cell
were broken down or altered there would be a " fault."
In works upon Physiology confusion is caused by the
uncertainty which attaches to the meaning of the word*
"stimulus," "impulse," "irritation," and "charge"
when applied to nerve cells, but if it be accepted that the
natural impulse is neuro-electrical, and that the changes
which take place in nerve-cells and processes are due to
alteration of nerve potential, sign of nerve current, or
variations of external or internal resistance, a clearer
appreciation of the laws which govern the nervous system
may be obtained.
In the same way we may find an explanation of uni-
polar, bipolar, and multipolar cells. The storage-ganglion
would be unipolar and the condenser-ganglion bipolar,
while a cell provided with two or more sets of alternatingly
conducting and insulating materials would naturally be
multipolar. Unfortunately the illustrations to be found in
works upon Physiology are not designed to show the
electrical structure of nerve cells and processes, and
therefore the difficulties in the path of the student are
great. That there is no book upon Biology or Botany
which gives any information upon the electrical structure
of any inhabitant of the vegetable kingdom is no longer to
be wondered at when some of the higher, forms of life are
little under stood. And yet, once the eye has been taught
to observe, that electrical structure is so clearly evident that
the most remarkable thing about it is the obscurity in which
it has remained.
Some further light is thrown upon the function of the
storage-ganglia by the electro-cardiograms given by athletes
after strenuous physical effort has exhausted their reserves.
Nature has to generate nerve force to supply the immediate
requirements of the body, and as part of this is, and must
202 STUDIES IN ELECTRO-PHYSIOLOGY:
be, taken up by the storage-ganglia to replace the charge
given out by them, the process of recovery, as shown by
the string galvanometer, is slow. The hypothesis, there-
fore, that the ganglion cells receive " charge " and not
'' irritations " seems to be tenable. In Thornton's Human
Physiology we are told that by a nerve-centre we must
understand a ganglion cell, or group of cells, capable of
receiving, modifying, and discharging nerve impulses, and
thus acting for the performance of some function. As I
have explained it, this is intelligible. Reject that explana-
tion and no one law remains to account for all the
phenomena. There can only be one law, and that law
applies with equal force to both the animal and vegetable
worlds. Every observed phenomenon must be in harmony
with it, if the observer is not in error.
Turning again to Thornton, the following passage is
worth quoting : " Experimental excitation shows that the
anterior root " (of a spinal nerve) " contains efferent fibres
and the posterior afferent fibres. . . . Other fibres pass
by these cells and do not appear to be connected with
them. What their nature is cannot yet be stated." All
this is consistent with condenser-action, and may be
explained by it. What appears to be required is that the
specialist physiologist should collaborate with the specialist
electrician in the study of the human nervous system, and
I think this will have to be done if appreciable progress is
to be made during our lifetime.
" Upon the object of autonomic ganglia I can find nothing
which conflicts with the views I hold. ..." Nature has,
as it were, before her the problem of supplying with nerves
the vast mass of muscles in the body, and the space at her
command in the various exits from the cranium and spinal
canal does not allow of more than a comparatively small
outflow from the central nervous system.
"The difficulty is met to some extent by the branching
ANIMAL AND VEGETABLE 208
of the out-flowing nerve-fibres, and in the case of the
voluntary muscles this appears to be sufficient. The
most striking example of this can be seen in the electrical
organ of the malapterurus, where the millions of its sub-
divisions on each side of the body are all supplied by the
branches of a single axis -cylinder process originating from
a single giant nerve-cell in the brain.
" But in the case of the involuntary muscular tissue
there is an additional means of distribution, for each fibre
that leaves the central nervous system arborises around a
number of cells in the autonomic ganglia, and thus the
impulse is transferred to a large number of new axis-
cylinder processes. . . . The afferent or sensory fibres are
much less numerous than those which are efferent. . . .
Thus in the splanchnic and hypogastric nerves about one-
tenth of the fibres are found to be sensory, and in the
pelvic nerve about one-third of the total fibres are sen-
sory." (Halliburton, 1915.)
UNIPOLAR AND BIPOLAR NERVE CELLS.
Unipolar cells, as I have stated, are, in my view, storage
cells, and appear to be prominently associated with the
closed circuits of the sensory nerves. In common with
other nerve-cells they contain at least one conducting
substance in organically combined iron (Macallum), and
non-conducting substances, possibly the deep and super-
ficial reticula described by Golgi and regarded by J. Turner
as investments derived from neuroglia cells. However
that may be, I am constrained to the opinion that in all
nerve-cells we have a form or forms of condenser or Leyden
jar ; that is to say, they may consist of one or more jars, and
that, if more than one, these elements may be connected in
series or in parallel, for the regulation, adjustment, and
distribution of tension.
204 STUDIES IN ELECTRO-PHYSIOLOGY:
The best illustrations I have been able to find are given
in Schaf er's Essentials of Histology, and I reproduce them
in the hope that the apparently electrical structure may
stimulate further research and pave the way to their
explanation in electrical as well as in physiological terms.
Before doing so, however, we may usefully remember
that " in the ganglia each nerve-cell has a nucleated sheath
which is continuous with the neurilemma of the nerve-fibre
with which the cell is connected ; that in the spinal
ganglia the axis-cylinder process divides into two within
the ganglion, one fibre passing to the nerve-centre and
the other towards the periphery ; while in the sympathetic
ganglia the nerve-cells usually have several dendrons and
one axon."
Furthermore, " the cells of ganglia are disposed in
aggregations of different size, separated by bundles of nerve-
fibres which are traversing the ganglion. The latter, if
large, is inclosed by an investing capsule of connective tissue
which is continuous with the epineurium and perineurium
of the entering and issuing nerve- trunks." (Schafer.)
A peculiarity which should not be lost sight of is that
in the spinal ganglia and in many of the corresponding
ganglia on the roots of the cranial nerves of mammals the
only issuing process is the axon, and when this divides into
two the branching is T-shaped or Y-shaped, and always
occurs at a node ofRanvier ; the neuro-fibrils of the central
and peripheral branches retaining their individuality in
the common trunk and being traceable into a neuro-fibril
network within the cell body.
And now, having collated these facts, let us remember
that an electrified ball exhibits the same tension on every part,
and see how this physical law agrees with the theory of
neuro- electrical cell-action, taking into consideration that,
while every cell in the body may be, in a sense, a condenser,
transmitting neuro- electrical impulses in various directions
ANIMAL AND VEGETABLE
205
and with varying tension, every cell is not of the same
structure or designed for the performance of the same
function. We must, therefore, examine them in detail and
have special regard to their formation, so far as it has been
made clear, or can be said to be suggestive to the electrician.
a
Fig. 109.
UNIPOLAR CELL from spinal ganglion of rabbit, a, axon ; 6, circum-
nuclear zone, poor in granules ; c, capsule ; d, network within nucleus ;
f, nucleolus. (After Schafer.)
Fig. 110.
BIPOLAR CELL (ganglion) of fish (Holmgren). It will be noticed that
the medullary sheath is continued as a thin layer over the cell-body.
(After Schafer.)
MULTIPOLAR CELLS.
So far, the cells appear to be more or less globular in
shape, and while the multipolar cells of the cerebral cortex
and spinal cord appear to differ materially, as a whole,
from those of the unipolar and bipolar type, they must
obey the law, and therefore possess, although perhaps in
a modified form, the same internal arrangement or
arrangements and similar absolute capsular insulation.
206 STUDIES IN ELECTRO-PHYSIOLOGY:
To the electrician the construction of a multipolar cell
to transmit efferent and afferent impulses would be a
comparatively simple matter. Take two hollow metal
globes or ellipses or modifications
^ e i tner > place one inside the
other in such manner that there
is an air-space or insulating layer
between them, and drill a hole in
the outer globe to receive an
Fig. ill. insulated wire, which would make
metallic contact with the inner
globe (Fig. 111). The next step would be to solder a
number of insulated wires to the outer globe, and to then
provide absolute insulation for the whole by coating the
outer globe with, say, gutta-percha solution or Chatterton's
compound.
Now, in a Ley den jar the inner and outer coatings are
metallic, the glass walls of the jar form the dielectric
substance, and discharge is prevented by the resistance
interposed by air intervening between the outer coating and
the earth. In the human body all the nerves are to earth,
through the air, and the resistance of that intervening
stratum of air is sufficiently great to prevent discharge,
under normal conditions of charge, taking place prematurely.
When, however, a motor or secretory nerve receives an
efferent impulse, or it may be impulses, the added tension
is just enough to bridge the spark gap, as it were, and so to
permit of a discharge or partial discharge.
It will be seen, however, that the surface area and
therefore the tension of the two globes, as sketched in
Fig. Ill, is not the same, and that if the impulse conveyed
by the axon were an efferent impulse all the wires connected
to the outer globe would transmit lower-tension afferent
impulses, in which case the cell would not be multipolar.
But in the majority at least of these cells there are
ANIMAL AND VEGETABLE 207
branch circuits, collaterals, or dendrons (corresponding to
our wires of the outer globe) which terminate in arborisa-
tions or end-organs, connecting, interlacing, or inter-
mingling with other nerve-cells, of which they are anato-
mically independent. These other cells and arborisations
act, as I have endeavoured to show, as condensers in
changing the sign of current or impulse, and, as I have
suggested, any variation of tension may be brought about
by varying the area of the condenser-plates, discs, or
points, or conducting cell areas.
In the typical multipolar cells of the spinal cord, as
shown by Max Schultze, only one process becomes the
axis-cylinder of a nerve-fibre, the others breaking up into
arborisations of fibrils which can be traced into the axon
and the other branches of the cell. " Between the fibrils
the protoplasm of the cell contains a number of angular or
spindle-shaped masses . . . known as Nissl's granules "
(see p. 189). " These nerve-cells often contain . . . granules
of pigment, usually yellow, the nature of which has not
been determined." As a matter of possibility, the yellow
pigment may be an insulating substance of the nature of
elastin, but as to this I am not, in the absence of any
definite information as to its chemical composition, able to
offer an opinion.
We may now compare a multipolar ganglion cell as
illustrated physiologically with the artificial contrivance
before mentioned. (Figs. 112, 113.)
Supposing an efferent impulse to be conveyed to the
inner globe, as shown in the electrical diagram, all the
discharge impulses would be afferent, and, as I before
remarked, the cell would not be multipolar. A condenser
of suitable capacity inserted between any one or more of
the terminals c, d, e, g, h, i, j, k, would retransform the
impulse from afferent to efferent, and either raise or further
lower the tension in accordance with its surface area,
208 STUDIES IN ELECTRO-PHYSIOLOGY
Physiological.
Electrical.
it.*-*,
Fig. 112. Fig. 118. (-4/ter Schafer.)
PHYSIOLOGICAL. A, large pyramidal cell of cerebral cortex, human. Nissl
method (Cajal). a, axon ; 6, cell body ; c, apical dendron ; d, placed between
two of the basal dendrons, points to the nucleus of a neuroglia cell ; diagram
reversed. Seven other branches, presumably dendrons, or collaterals, are shown,
and these must interlace, by means of their arborisations, with other cells.
ELECTRICAL. B, battery ; a, axon or line-wire ; b, insulating cover or
capsule ; c, rf, e, g, h, i, j, k t branches from outer globe.
while, if it was desired to retain an afferent impulse at any
point, no condenser would be inserted at that point.
Physiologically, of course, the dendrons would inductively
connect with neighbouring cells by means of their arborisa-
tions ; electrically the condensers, when inserted, would be
connected more or less as shown in Fig. 114.
It is quite evident, however, that this explanation of
the functioning of a multipolar cell is insufficient. Suppos-
ing the inner and outer globes to act as a Leyden jar, all
the impulses, efferent and afferent, would be conveyed
simultaneously with each discharge, and while Nature does
not waste any impulse but utilises it in the motor, secretory,
ANIMAL AND VEGETABLE
209
and some sensory paths, it seems to me improbable that
action takes place in the manner I have described. Even
if the branch circuits or collaterals, with their inductive
effect upon cells contiguous to them, were of different
resistance and the cells of varying capacity, the impulses
would still be simultaneous, though varied as to tension.
We must therefore, I think, come to the conclusion that
- ffttro'/tigh ran
Fig. 114.
Diagram, showing how an artificial multipolar cell circuit might be
arranged to give any number of efferent and afferent impulses.
instead of a multipolar ganglion cell being made up of one
Ley den jar with multiple connections, it is made up of
many such jars or rings, and that the axis-cylinder process
divides, not into two, but into as many independent or,
in other words, insulated fibres or fibrils as there are
collaterals, and that each of these fibrils leads to a separate,
though perhaps not anatomically distinct, condenser or
jar, and, inductively, through that jar to the dendron
designed to convey a specific impulse, efferent or afferent.
p
210 STUDIES IN ELECTRO-PHYSIOLOGY:
I am encouraged in this opinion by a careful study of
the structure of unipolar cells and by other considerations.
To my mind it would appear that the structure of even the
unipolar cell is not simple but complex. It seems to be
circular in form throughout to be, in fact, a series of rings ;
and while the microscope has not, so far, given us the
needful detail, it does not call for an undue stretch of the
imagination to believe that it may, possibly, be composed cf
a series of Leyden jars ; that is to say, circular layers of
conducting substances with non-conducting substances
between them, and that such layers, like the sarcomeres,
are insulated from each other and are in connection with
certain assigned nerve-fibres or fibrils. In such case we
can conceive in a multipolar cell the impulse being given,
as a whole, from a principal central system, or, individually*
to any dendron or branch circuit.
Since writing the foregoing my attention has been
drawn to an illustration in HaeckePs Evolution of Man
(taken from Max Schultze) of a multipolar cell from the
brain of an electric fish, and as it seems to confirm my
theory I reproduce it. (Fig. 115.)
Reverting to the typical multipolar cell of the spinal
cord, and at the risk of repetition, I must remind my
readers that the axis-cylinder process itself invariably
gives off side branches or collaterals, which pass into the
adjacent nerve-tissue. " The axis-cylinder then acquires
the sheaths, and thus is converted into a nerve-fibre.
This nerve-fibre sometimes, as in the nerve-centres after a
more or less extended course, breaks up into a terminal
arborescence enveloping other nerve-cells ; the collaterals
also terminate in a similar way ... all ultimately ter-
minate in an arborescence of fibrils in various end- organs
(end-plates, muscle-spindles, etc.)."
Furthermore, " each nerve-unit (cell, plus branches of
both kinds) is anatomically independent of every other
ANIMAL AND VEGETABLE 211
nerve-unit. There is no true anastomosis of the branches
from one nerve-cell with those of another, and nerve
impulses are transmitted from one nerve-unit to another,
Fig. 115.
A LARGE BRANCHING NERVE-CELL, from the brain of an electric fish
(Torpedo), magnified 600 times. In the middle of the cell is the large
transparent round nucleus, one nuckolus, and, within the latter again, a
nucleolinus. The protoplasm of the cell is split into innumerable fine
threads (or fibrils), which are embedded in intercellular matter, and are
prolonged into the branching processes of the cell (fe). One branch (a)
passes into a nerve-fibre. (From Max Schultze.)
through contiguous but not through continuous structures.'
(Halliburton.)
212 STUDIES IN ELECTRO-PHYSIOLOGY:
The following illustration is given to explain reflex
action :
t^
ACC
Fig. 116. REFLEX ACTION. (After Hallibwton.)
Excitation occurs, we will say, at a sensory surface S,
and the impulse is transmitted by the sensory nerve-fibre
to the central nervous system. " This fibre does not
become anatomically connected to any of the cells of the
central nervous system. The only cell -body in actual
continuity with the sensory nerve-fibre is the one in the
spinal ganglion (G) " (a storage cell). " On entering the
spinal cord the main fibre conveys impulses upwards which
ultimately reach the brain, but in the spinal cord it gives
off fine side branches or collaterals which terminate by
arborising around one or more cell -bodies and their den-
drons ; these cells are small ones situated in the posterior
cornu of the spinal grey matter ; one only (PCC) is shown
in the diagram. The short axon of this cell similarly ter-
minates by a synaptic junction with one or more of the
large multipolar cells of the anterior cornu of the spinal
grey matter ; one of these shown in the figure is labelled
ACC. This motor cell is thus stirred up to action and
sends an impulse by its axon to the muscular fibres it
supplies." (Halliburton.)
I may remark, in parenthesis, that we have here
evidence of condenser-action, of cells changing the sign of
ANIMAL AND VEGETABLE 213
current and transforming, in a shunt-circuit, an afferent
to an efferent impulse. The correct number of cells is not
shown, but any even number between G and ACC or any
uneven number between the sensory nerve-fibre and the
motor fibre would do it.
Halliburton avers that : " The synaptic junctions are
naturally the places which the impulse has the greatest
difficulty in traversing ; and some observers believe that at the
points of contact there is a kind of undifferentiated interstitial
protoplasm which the impulse has to get through." *
Suppose there to be many thousands of such synaptic
junctions, or, electrically speaking, many thousands of
condensers of varying capacity, concentrated over a length
of, say, three feet, and further suppose them to be ulti-
mately connected to a copper wire of three feet in length
to earth through a high resistance at its further end. Let
the condenser-length be from A to B and the wire-length
from B to C. Would the velocity of a current of electricity
sent from A to B be the same as from B to C ?
Obviously it would not, could not, be.
Going back, after these interpolations, to our diagram
of reflex action, the electrical impulse, due to alteration of
resistance at S caused by, for instance, a rise or fall of
temperature, by pressure upon the skin, etc., would be
afferent. Upon reaching the storage cell, G, it would be
affected or unaffected by difference or non-difference of
potential between sensory nerve-fibre and cell. If the cell
held its normal charge, the impulse would pass unaltered
(by that cell) on its path to the brain. If, however, the
potential of the cell was higher than that of the fibre, the
impulse would be increased or accelerated, and vice versa.
At the point PCC, the cell there would be in an inductive
* The italics are my own and are intended to suggest a reason, one
reason, for the comparatively very low velocity of the nerve-current as
compared with that of electricity along a wire or cable.
214 STUDIES IN] ELECTRO-PHYSIOLOGY
shunt-circuit, and would transform some portion of the
afferent impulse to an efferent one, should no other cell be
between it and the muscular fibre. The multipolar cell, ACC,
being interposed, it follows that one cell between the sensory
nerve and the muscular nerve-fibre is omitted in the diagram.
" For a reflex action," remarks Halliburton, " three
things are necessary : (1) an afferent nerve, (2) a nerve-
centre consisting of nerve-cells to receive the afferent
impulse and send out the efferent impulse, and (3) an
efferent nerve along which the efferent impulse may
travel." Verb. sap.
I have said that in my view unipolar cells are of the
storage type and appear to be prominently associated with
Fig. 117.
Shows on the left the motor nuclei and efferent fibres, except those of
the fourth nerve, and on the right side the afferent fibres. (After Schafer.)
sensory nerve-fibres ; their function, mainly if not entirely,
being to maintain equilibrium in a closed-circuit system.
In this connection there are at least two diagrams in
Schafer's Essentials of Histology which support my view,
ANIMAL AND VEGETABLE
215
and I am of opinion that if we had a complete plan of the
nervous system, showing the whole of the efferent and
afferent nerve- fibres and all the intervening cells, with their
arborisations, so that the different circuits could be traced,
my contention as to condenser-action in the body would be
more than amply justified.
The first of the diagrams to which I have referred is
given in the chapter upon the Medulla Oblongata, and is
intended to illustrate the origin and relations of the root-
fibres of the cranial nerves (Fig. 117).
There is a further diagram of the efferent fibres only,
but no unipolar or storage cell appears.
The second diagram to which I have alluded is given in
the chapter upon the Pons Varolii, and is a plan of the
origin of the fifth nerve :
Fig. 118.
G, Gasserion ganglion ; a, &, c, three divisions of the nerve ;
superior motor nucleus ; mnv, principal motor nucleus ; psnv, principal
sensory nucleus ; asnv, dnsv, descending sensory nucleus ; dsv, descending
root ; cv, c'v, central sensory tracts composed of fibres emanating from
the sensory nuclei ; r, plane of the raphe. (After Schdfer.)
216 STUDIES IN ELECTRO-PHYSIOLOGY:
The fifth or trigeminal nerve, it is scarcely necessary to
remark, emerges at the side of the pons in two roots, a
small motor and a large sensory, and it is only in connection
with the sensory nerve that we find the spherical unipolar
cells associated. The^motor root, as one might expect, is
provided with numerous multipolar cells, so that it cannot
be said to be entirely distinct from the larger posterior
sensory root with which it emerges, inasmuch as any
branch of it can be made afferent, although not sensory in
the sense of a closed circuit, by the insertion of a bipolar
cell between a motor nerve-fibre and a branch.
Before concluding this study I should like my readers
to take careful note that in the course of voluntary motor
fibres, before they pass into the anterior root (spinal cord)
they always first form connections with the multipolar
nerve-cells of the anterior cornu, which, in fact, are intro-
duced into the course of the conducting-paths ; but, in
their passage through the brain, the paths for direct motor
impulses are not interrupted anywhere in their course by
ganglion cells, not even in the corpus striatum or pons.
They pass in a direct uninterrupted course.
ANIMAL AND VEGETABLE 217
CHAPTER XVI
THE EYE AND THE EAR
THE EYE
IF I shrink from giving a detailed description of the
manner in which I believe these two organs of special sense
operate, it is not because the task is beyond me, but because,
owing to my limited knowledge of histology and the
paucity of information as regards the neuro-electrical
ramifications of the circuits for my enlightenment, I
grudge the time that would have to be spent in further
research ; whereas a physiologist who could bring himself
to ponder the matter from a purely electrical, or rather
from a purely telegraphic and telephonic point of view,
would, I have no doubt, be able to do the subject greater
justice.
At the same time, it is incumbent upon me to put upon
record my opinion that the eye is strongly suggestive of a
compound selenium-cell transmitting apparatus, and that
the ear does not differ in any essential respect from a
telephone system, the outer ear being the receiver, the
middle ear the microphone, and the auditory nerve the
line wire or wires to the brain.
The element called selenium is not very well known
outside the precincts of the laboratory. It was discovered
in the year 1817 in the refuse of a sulphuric acid
manufactory in Sweden by' Berzelius, and is obtained in
two forms, one of which is soluble in carbon disulphide,
the other being insoluble in the same medium. The first
218 STUDIES IN ELECTRO-PHYSIOLOGY:
is of a reddish-yellow colour, conducting heat badly and
electricity not at all, while the other variety known as
black or metallic selenium conducts heat, and under certain
conditions will form a good conductor of electricity. It is
with the latter only that we are concerned.
In 1873 Mr. Willoughby Smith, then electrician-in-chief
to the Telegraph Construction and Maintenance Company,
discovered that this substance had a peculiar property in
that its electrical resistance varied with the amount of light
to which it was subjected ; the difference in these varia-
tions being very marked, and in the inverse ratio to the
degree of light. Later on Dr. Siemens, Professor Adams,
the Earl of Rosse, and other scientific men took up the
subject, but nothing practical was done until Professor
Graham Bell, in association with Mr. Sumner Tainter,
produced the photophone, an instrument in which light
was utilised for the transmission of sound.
Of more interest to us, however, is the " Selenium
eye " of Dr. Siemens. It was in reality an artificial human
eye, with a lens in front, and lids to close when it was
weary ; for, curious as it may seem, it, like its perfect
prototype, became tired when exposed for a prolonged
period to bright light.
The lens caused any light to which the " eye " was
subjected to be concentrated in the interior of the eyeball,
and at this spot a selenium grating was placed. This was
composed of two fine wires running together in zigzag
fashion, but not making actual contact. Upon these was
placed a melted drop of selenium, and the ends of the wires
were joined up with a galvanometer and battery. When
the " eye " had been closed and at rest for some little time,
it was found to be sensitive to the faintest gleam of light,
but after long exposure to bright light the lids closed for
a long time before it became again sensitive to feeble rays.
Since then much experimental work has been done, and
ANIMAL AND VEGETABLE 219
inventions of scientific interest but no great commercial
value have resulted.
One of the most successful attempts the in-
vention of a Pole named Szczepanik to transmit pictures
to a distance by the agency of selenium was described in
Pearson's Magazine of October, 1899, by Mr. Cleveland
Moffett. It was called the " Telectroscope," and was
founded upon the fact that any vision or image produced
upon the retina is only the blending together of an infinite
number of points projected separately from the object and
seen by separate rays of light. Some of these come a
fraction of a second later than others, but if the intervals
between them be short enough persistence of vision will
have the effect of bringing them together and forming a
complete picture.
From the article in question I gather that Szczepanik
devised a way of separating any image formed by an
ordinary photographic lens into its component luminous
points, of transmitting these points separately, but with
enormous rapidity, over wires, and letting the eye recon-
stitute them at the other end into the original picture.
Selenium, it may be said, possesses the peculiar property
of transforming waves of light into waves of electricity,
so that if rays of light are thrown upon a selenium disc
to which insulated wires are connected, it will be found that
currents are set up in the wires, and moreover that rays of
light differing in colour and intensity give rise to currents
which also differ in intensity ; each particular 1 ray having
its corresponding current, and no two of them being exactly
alike.
Szczepanik's transmitting apparatus consisted of a box
with a camera front and a photographic lens for focussing
an image outside the box upon two vibrating mirrors,
designed to resolve the image into points and project these
upon a selenium disc connected by wires with the receiving
220 STUDIES IN ELECTRO-PHYSIOLOGY:
apparatus. The transmitting wires terminated in two
vibrating metal plates, contained in another enclosed box
with a camera front, and these plates, by an ingenious
method of lighting, allowed a changing band of light, as
thin as a hair, to pass between them. This was broken
up in turn by two' other vibrating mirrors and projected
upon a ground-glass plate, upon which the transmitted
image appeared.
The inventor solved the problem of the conveyance of
colour by passing the rays of light received by the lens in
the transmitter and from the vibrating metal plates of the
receiver through a prism, each ray being deflected more or
less and each having an individual deflection ; a violet ray
being deflected more than a yellow ray, and a red ray less
than a green one, and so on.
With the technical details of the Telestroscope we need
have no further concern. Its interest, to me, lies not in
the mechanical details they were necessitated by the fact
of there being only one selenium disc in the transmitting
apparatus but in certain curious points of resemblance
to the human eye.
If, instead of one transmitting disc and two connecting
wires, an infinite number of such discs and wires could have
been employed, there would have been no occasion for the
vibrating mirrors, for the reason that the " points "
projected separately from the object would be received
upon a large number of discs and conveyed to the brain
by a large number of wires or nerve-fibres. The number
of fibres in the optic nerve is said to be upwards of 500,000,
while the number of cones in the rod and cone layer of the
eye of man the nerve- epithelium of the retina has been
estimated at 3,000,000.
It does not follow that these discs and wires are as
multitudinous as the points of light which in their entirety
form a % picture or an image. It is because they are not so,
ANIMAL AND VEGETABLE
221
I take it, that there is such a thing as memory of the eye,
or persistence of vision.
Comparing the lens of the eye with that of a camera, the
iris is the diaphragm to regulate the aperture, and the rays
or points of light admitted by the lens are thrown, although
not directly, upon a layer of pigment cells which form
the outer or choroidal surface of the retina.
It should also be noted that posteriorly to the iris is a
layer of pigment cells, a continuation forwards of the
pigment layer of the retina.
Fig. 119. PIOMENTED EPITHELIUM OF THE HUMAN RETINA.. (Max
Schultze.)
a, cells seen from the outer surface with clear lines of intercellular
substance between ; b, two cells seen in profile with fine offsets extending
inwards ; c, a cell still in connection with the outer ends of the rods.
In colour these pigment cells appear to be dark brown,
and, like the macula lutea, apart from the fovea centralis,
non-actinic.
It will be seen, from b and c, that fine offsets or nerve-
fibres extend inwards from these cells, and, presumably,
either make connection with or influence the rods and
cones in their immediate vicinity ; these rods and cones
222 STUDIES IN ELECTRO-PHYSIOLOGY:
connecting by means of various nerve processes and gan-
glionic cells with the brain.
" At the fovea each cone is connected to a separate
chain of neurons, whereas in other regions the rods and
cones are connected in groups to these chains. ... At
the exit of the optic nerve the only structures present are
nerve-fibres. . . . The nerve-cells in the retina remind us
that the optic, like the olfactory nerve, is not a mere nerve
but an outgrowth of the brain." (Halliburton.)
The clearest, if not the most comprehensive, exposition
of the structure and functioning of the eye, so far as my
reading goes, is contained in Thornton's Human Physiology.
Briefly summarising this, I learn that the outermost layer
of the retina next to the choroid consists of a single stratum
of hexagonal epithelium containing black but, according
to Schafer, dark brown pigment. They are present in
all parts of the retina, except at the entrance of the optic
nerve. The outer surface of the cells is smooth and flat,
but the inner part is prolonged into fine processes which
extend between the rods. About 7,000 cones are said to
exist in the fovea. Near the macula lutea the retina
contains one cone to four rods ; midway to its termination
at the ora serrata one cone to twenty -four rods ; at the
peripheral part rods only.
Visual impulses begin in the rods and cones on the outer
side of the retina, after the rays of light have passed
through most of the retinal layers, and the processes
started in these sensory epithelial cells of the retina pass
back to the layer of fibres on the inner surface of the retina
and thence by the optic nerve to the brain.
We know that the retinal vessels are distributed in the
inner layers (nerve-fibres and ganglionic cells) of the
retina, and the shadows cast behind them must be per-
ceived by something posterior to those vessels. This is a clear
proof, it is said, that the external layers of the retina nearest
ANIMAL AND VEGETABLE 223
the choroid, that is, the rods and cones, are the elements
in which the visual impressions begin.
46 It thus appears that the real end-organs of vision,
the rods and cones, must be in some way connected func-
tionally, if not structurally, with the nerve filaments that
pass to the optic nerve, and it is evident that these rods
and cones, being backwards from the light towards the
sclerotic, must receive the light waves after they have
passed through the internal layers of the retina, except at
the f ovea, where, all the other layers having thinned off,
the basal fibres of the cones themselves are directly exposed
to the light waves." (Thornton.)
Before we accept the above conclusions as final it will
be well to ponder the matter carefully.
There are several points which call for consideration.
Cones are absent in some animals and rods in others.
Light produces changes in pigment, but while the outer
limbs of the rods are tinged with a pigment termed
" visual purple," derived from the pigment cells of the
outer layer of the retina, it can hardly be essential to vision,
as it is " absent from the cones of the fovea and entirely
wanting in some animals that see well."
I am not going to suggest that the epithelial pigment
cells of the retina contain selenium, but I do suggest that
they are composed of or contain some substance which
has the property of transforming waves of light into waves
of neuro-electricity, possibly by causing enormously rapid
alterations of resistance in the sensory nerve- circuits
connected functionally, if not structurally, with the cells^
" We do not know," says Thornton, " how the undula.
tions of light become converted into nervous impulses that
give rise to visual sensations."
The three following diagrams (Figs. 120, 121, 122) may
with advantage be considered in their relation to the known
optical law that " ordinary light consists of vibrations
224 STUDIES IN ELECTRO-PHYSIOLOGY:
taking place always in planes at right angles to the
direction of the ray, but in all directions in those planes.
That is, if the ray travels along the axle of a wheel, the
vibrations composing it are all in the plane of the wheel,
but are executed along any or all of the spokes." (Gordon's
Electricity and Magnetism.)
Rays of light, entering at the lens, would, if the lens
were a fixed object, approximate to the axle, and the rods
and cones to the spokes of the wheel. But the lens is not
a fixed object, as in a camera. It not only receives rays
of light from above, below, and each side, but continually
shifts its angle of reception of such rays by movement of
the eye.
Fig. 120.
Diagram of a section through the (right) human eye passing horizontally
nearly through the middle, a, b, equator ; y, optic axis. (After Schafer.)
The pigmented cells of the outer or choroidal surface
are not shown in Fig. 121, but are illustrated by Schultze
in a diagrammatic section of the human retina (Fig. 122).
ANIMAL AND VEGETABLE
225
Fig. 121.
Vertical section through the Macula Lutea and Fovea Centrah's;
diagrammatic. (Thornton, after M. Schultze.)
1, nerve layer ; 2, ganglionic layer ; 3, inner molecular, 4, inner nuclear,
and 5, outer molecular layers ; 6, outer nuclear layer, the inner part with
only cone fibres forming the so-called external fibrous'layer f 7, cones'and
rods. f& 31T.
Outer or Ckorou&zl /
4 Inner Tiuclear or bipolar iayr
nfar
Fig. 122. DIAGRAMMATIC SECTION OF THE HUMAN RETINA. (After
M. Schultze and Schdfer.)
226 STUDIES IN ELECTRO-PHYSIOLOGY:
From the two previous diagrams it will be seen that,
as in Szczepanik's apparatus, the rays of light are broken up
and deflected at various angles before they reach the
pigmented cells or the rods and cones, and I assume that*
having arrived at, as it were, a terminal, they are, at that
terminal, transformed into waves of neuro-electricity,
which, picked up by the rods and cones, are conveyed in
that form to the brain.
If something of that kind does not occur we are con-
fronted with another very extraordinary coincidence.
In the Science of Light, by Percy Phillips, D.Sc., it is said :
" If we suppose that the sensation of light is due somehow
to the vibrations of electrons in the retina, the retina itself
will do instead of a prism for drawing out a pulse into
waves, and so we may have interference even without the
prism. We see, therefore, that it is just as simple to
imagine that the regular trains of waves are produced by
the receiver as by the transmitter of the wave. We only
need assume regularity of period in one or other of them.'*
The theory that the sensation of sight is due to the
direct action of the vibrations of electrons in the retina
calls for examination. It has not been finally and con-
clusively proved that light consists of short electro-magnetic
waves. The strongest argument in its favour is Maxwell's
calculation that the speed of electro-magnetic waves agrees
with that of light, i.e., 300,000,000 metres per second.
That is equivalent to a velocity of 12,000,000,000 in. per
second, and taking the distance between the lens of the eye
and the receptive organ or organs of the brain to be, say,
6 in., impulses would, according to that theory, be trans-
mitted in 23^ millionth of a second.
Moreover, these electro-magnetic waves would impinge
directly upon the layer of optic nerve-fibres, thence upon
the optic nerve-cells, and exert their electronic vibratory
influence upon five other layers of the retina before reaching
ANIMAL AND VEGETABLE 227
the rods and cones, which we are told are the structures
directly concerned with vision.
In the conversion of rays of light into waves of neuro-
electricity delays which would reduce the rate of trans-
mission to the normal velocity of nervous impulse would
most certainly occur at the synapses, and quite apart from
physiological research we can be reasonably sure that the
impulses to which vision is due do not travel at anything
like the rate at which electro-magnetic waves are pro-
pagated. Halliburton says : " The duration of the sensa-
tion produced by a luminous impression on the retina is
always greater than that of the impression which produces
it. However brief the luminous impression, the effect on
the retina always lasts for about one-eighth of a second.*'
That is, in perfect harmony with an electrical impulse,
which, as we have seen (p. 160), always takes longer to
leave the circuit than it did to enter it, but it is not in
harmony with the theory that impulses are conveyed to the
brain at a velocity of 300,000,000 metres instead of 120
metres per second. In the one-eighth of a second during
which the retina retains the impression no fewer than
1,500,000,000 impulses would be produced by the direct
vibrations of electrons, and they would continue to arrive
at the same speed while vision lasted.
Some further arguments in favour of the theory I have
advanced may, however, be adduced.
I have said that, in my opinion, the optic, like the
auditory, nerves and we must include their processes
are " closed " circuits. Halliburton states that the
retina " possesses a store of potential energy which the
stimulus serves to fire off." That is understandable in a
closed, but not in an open, circuit.
44 Nothing is known about the yellow pigment of the
yellow spot," but a 4t change produced by the action of
light upon the retina is the movement of the pigment cell*.
228 STUDIES IN ELECTRO-PHYSIOLOGY:
On being stimulated by light the granules of pigment in the
cells which overlie the outer part of the rod and cone layer
of the retina pass down into the processes of the cells,
which hang down between the rods " (see Fig. 119) ;
" these melanin orfuscin granules are generally rod-shaped,
and look almost like crystals. In addition to this, a
movement of the cones and possibly of the rods occurs ; in
the light the cones shorten, and in the dark they lengthen.*'
(Halliburton : Engelmann.)
The property of transforming rays of light into nervous
impulses may reside in the " visual purple," but if the
pigment cells have no part in this and are designed merely
to provide the dark lining of the camera, why should they
be given movement, and why do they have processes
connecting, functionally if not structurally, with the rod
and cone layer ?
THE EAR.
The ear is divisible into three parts: i.e., the external
ear, the middle ear or tympanum, and the internal ear or
labyrinth. Physiologically described, " the filaments of
the auditory nerve end in peculiar structures buried
deeply in the hard portion of the temporal bone of the
skull, and special arrangements exist for conducting waves
of sound to this deeply seated sensitive part. The external
ear assists in collecting sonorous vibrations that pass along
a channel termed the external auditory meatus, and
impinge against a stretched membrane called the tympanic
membrane, or drum-skin. The vibrations thus set up in
the tympanic membrane are transmitted across the
tympanic cavity or middle ear by a chain of small bones
the malleus or hammer, the incus or anvil, and the
stapes or stirrup to the inner ear. The membranous
base of the stapes is placed in connection with the inner
ANIMAL AND VEGETABLE 229
ear by being fixed into an oval opening in a bony tubular
labyrinth consisting of parts termed the vestibule, the
semicircular canals, and the cochlea. Inside the bony
labyrinth is a nearly similar labyrinth of membrane filled
with liquid, a liquid also lying between the bony and the
membranous labyrinth."
Fig. 123. SCHEME OF THE ORGAN OF HEARING. (Landxris and Stirling.)
HG, external auditory meatus ; T, tympanic membrane ; malleus
with its head, short process (kf), and handle (w) ; a, incus with its
short process (x) and long process the latter is united to the stapes (s)
by means of the Sylvian ossicle (z) ; P, middle ear ; o, fenestra ovalis ;
r, fenestra rotunda ; x, beginning of the lamina spiralis of the cochlea ;
pt y its scala tympani, and vt, its scala vestibuli ; V, vestibule ; S, saccule ;
U, utricle ; H, semicircular canals ; TE, Eustachian tube. The long
arrow indicates the line of traction of the tensor tympani ; the short
curved one, that of the stapedius.
These liquids are known as endolymph and perilymph
respectively, and according to Landois and Stirling the
end-organs of the acoustic nerve lie in the endolymph and
on membranous expansions of the cochlea and semi-
circular canals.
" The vibrations conveyed to this fluid by the move-
ment of the base of the stapes excite the peculiar epithelium
of the inner surface of the membranous labyrinth, on and
in which are distributed the auditory nerve-filaments.
Impulses pass from these filaments along the nerve lying
in the internal meatus to the brain, and there produce that
230 STUDIES IN ELECTRO-PHYSIOLOGY:
modification of consciousness which we call the sensation
of sound." (Thornton.)
Landois and Stirling say : " Normal hearing takes
place through the external auditory meatus. The enor-
mous vibrations of air first set the tympanic membrane in
vibration ; this moves the malleus (Fig. 128), whose
long process is inserted into it ; the malleus moves the
incus (a), and this the stapes (s), which transfers the move-
ments of its plate to the perilymph of the labyrinth."
All this, up to and including the movements of the
stapes, is perfectly consistent and indeed almost identical
with a telephone receiver and microphone attachment,
but when it becomes a question of transfer of mechanical
vibrations to nerve-filaments, or to the wires of a closed
circuit, I would point out that there is no evidence that the
true function of a nerve is to convey mechanical impulses.
The physiological theory is that the nerve impulse is
chemical. My contention is that it is neuro- electrical. It
is difficult to understand how mechanical vibrations can
be transformed into chemical impulses, but not at all
difficult to conceive them being neuro- electrically trans-
mitted over a closed telephone circuit.
Thornton remarks : " The whole subject of the
mechanism of hearing is far from being satisfactorily
settled. . . . For hearing the stimulus is of a mechanical
nature." 1 venture to think that the utmost that can be
said in favour of this hypothesis is that mechanical
stimulus extends from the external meatus, by the endo-
lymph, to the auditory nerve. It is the nerve, not the
endolymph, which conveys the stimuli to the brain.
I can offer one very convincing proof that in this case
at least the impulse is neuro- electrical. In purely nerve
deafness the measure of nervous energy, as shown by the
hand-to-hand galvanometric deflection, is not more than
30 or 40 mm. ; deflections from the back of the cartilage
ANIMAL AND VEGETABLE 231
of the external meatus, where it adjoins the mastoid, being
in accordance with that deflection, or, in other words, not
exhibiting departure from Ohm's law.
In such cases, if a rod of specially prepared carbon is held
by the patient for a few moments in the right hand so that
the body may receive a charge of the form of energy
exerted by it, the hand-to-hand deflection will rise to over
300 mm. positive, and hearing will usually return at once
and remain normal during such time as the charge is
retained.
Halliburton says : " The external and middle ears are
conducting ; the internal ear is conducting and receptive.
In the external ear the vibrations travel through air ; in
the middle ear through solid structures membranes and
bones ; and in the internal ear through fluid, first through
the perilymph on the far side of the fenestra ovalis, and
then the vibrations pass through the basilar membrane
and membrane of Reissner, and set the endolymph of the
canal of the cochlea in motion."
With great reluctance I must to some extent disagree.
The external ear, in my view, is receptive, in the sense that
the transmitter of a telephone is receptive of sound ; the
middle ear is receptive and conducting as a microphone
receives and conducts ; while the inner ear transforms the
vibrations transmitted, and probably amplified, by the
middle ear or microphone, into neuro- electrical impulses,
and conveys them in that form to the brain.
One thing, I think, can be regarded as certain. The
sensory nerves, and the nerves of special sense, are
" closed " circuits. That being so it follows, logically,
that the quantity of endolymph or perilymph, or both, in
the cochlea must not undergo diminution that is a matter
of the chemistry of the body and that the neuro-electrical
pressure, or electromotive force, present in those " closed "
circuits and energising the endolymph and (or) perilymph
232 STUDIES IN ELECTRO-PHYSIOLOGY:
must be fully maintained, if normal conditions are to be
preserved.
Supposing any " faults " to occur, at least three of
them should be susceptible to electro -diagnosis
(1) The drum of the ear may be thickened or overlaid
by inflamed tissue due to, say, inflammation or
rheumatoid conditions.
(2) The bones of the middle ear may be clogged by
catarrh, or urates, so that they are not free to
vibrate ; or
(3) The auditory nerve, or line wire, may be faulty.
In either case the vibrations do not reach the brain
unimpaired, because
(1) They are partly or wholly stopped, or rendered
" woolly " by the drum.
(2) If responded to by the drum they fail to set fully
in motion the clogged bones of the middle ear,
or at all ; or
(2) The faulty line wire fails to carry them fully, or
at all, to the brain.
We have, then, at least three morbid conditions to deal
with, and when one of these conditions occurs the telephone
system must be tested and the nature and locality of the
" fault " ascertained.
If the drum of the ear is thickened, or the passage to it
swollen, by rheumatoid arthritis or other causes con-
tributory to local pyrexia, it will yield an abnormal, that
is to say a high, deflection. So will the middle ear tested
by placing a suitable electrode between the mastoid and
the cartilage of the external ear if it is affected by
catarrh ; or it will give a subnormal deflection when the
bones are, and have been for some time, clogged by urates.
In much the same way the inner ear (the line wire) can be
made to disclose its degree of conductivity by giving the
ANIMAL AND VEGETABLE 233
measure of the nerve-current in it as compared with the
nerve-current present in the auditory nerve of a healthy
person of similar hand-to-hand deflection. If it is partially
atrophied the first step should, I think, be to restore it to
its normal condition of an active closed circuit ; by, say,
ionic medication.
In the case of catarrh of the middle ear, or of the
presence of inspissated mucus in the middle ear, our object
should be to introduce a harmless solvent into what is,
practically, a closed cavity.
234 STUDIES IN ELECTRO-PHYSIOLOGY:
CHAPTER XVII
ELECTRO DIAGNOSIS
THE GALVANOMETER AND ELECTRODES
AND How TO USE THEM
THE chief requirements in a galvanometer are great
sensibility and perfect insulation combined with a short
period of oscillation. There are several types, but in
practice I prefer for research work the special form of
Kelvin reflecting Astatic, made for me by Elliott Bros.,
although it is somewhat expensive. This instrument is
designed for tests where specially good insulation of all
parts of the circuit is required. There are eight coils,
having a total resistance of from 60,000 to 100,000 ohms,
carried in hinged frames supported by ebonite pillars ;
four terminals carried on tall ebonite stems through the
top of the case, and a long suspension.
The medical practitioner will be quite safe, as regards
sensibility, in ordering an instrument which will give a
deflection of 4,000 or more mm., at a scale distance of
1 metre, per micro-ampere. The period should not be
more than seven seconds.
On the next page will be found an illustration of the
instrument I have mentioned.
As shown it is not adjusted. To do this it is necessary
that it should be placed in the east (facing west), looking
towards the scale which is from 1 metre to 41 in. distant.
If it is stood upon wood the levelling screws should rest in
ANIMAL AND VEGETABLE 285
ebonite cups, but a good plan is to let a slate or marble
slab into the wall and stand the galvanometer upon it.
At the base of the instrument are two spirit-levels, and
the next thing to be done is, by manipulation of the
levelling screws, to see that each air-bubble lies exactly in
the centre.
Fig. 124.
Rising from the top of the case will be seen four
terminals and a central brass pillar. Unscrew the
236 STUDIES IN ELECTRO-PHYSIOLOGY:
latter. Beneath it is a pin, with a milled head (Fig. 125) to
which the suspension is attached. Raise this
pin, without turning, very gently, until the mirr or
jbiniiiiimninmm .
is exactly in the centre of the opening and
the suspension swings freely. Then replace,
and adjust the controlling magnet shown
Fig. 125.
underneath the instrument in the figure given.
To do this take off the screw at the top of the rod and
slide the magnet off. Then screw the rod into its seat,
replace the magnet due north and south and the screw
and the galvanometer is nearly ready for use.
Should it be necessary at any time to examine the
suspension, first take off the two screws which clamp the
case to the base, remove the terminals and the ebonite
discs below them and the pillar, having first detached
the controlling device by sliding off the magnet and
unscrewing the rod. The case can now be lifted off
bodily.
The next procedure is to remove the coil connection at
the left-hand inner terminal, and, also on the left, there
is a screw with a milled head. When this is taken out the
front coils will swing to the right on their hinges and expose
the suspension.
Sometimes a hair, a microscopical fragment of silk from
the suspension, may connect some part of the latter with
the casing and give trouble. Upon opening the coils this
may be detected.
A hole, covered by a slide, at the top of the case is for
the insertion of a thermometer.
As the Kelvin galvanometer is so well known, a tech-
nical description of it is unnecessary. There are several
points in connection with it, however, to which attention
may usefully be called.
If the instrument is placed in the east and facing west
the suspension will, before the controlling magnet is in
ANIMAL AND VEGETABLE 237
position, come to rest in the plane of the magnetic meridian,
because very small permanent magnets are affixed trans-
versely thereto, and must, consequently, fall into line with
the earth's magnetism. The purpose of the controlling
magnet is to obtain a position in which it quite neutralises
the earth's magnetism. To adjust zero, therefore, a rough
approximation to it should be made, before the controlling
magnet is in place, by turning the milled suspension pin
to the right or left as the case may be but avoiding any-
thing approaching a complete turn then putting on the
controlling magnet and moving it gently out of the north
and south until the reflected spot of light nears the zero of
the scale. Further and more delicate adjustments may be
made by turning the screw at the back of the pillar, and
that operating the ratchet upon the scale-stand.
Sensibility may be varied by, also very gently, moving
the controlling magnet up or down its support.
Advantage may be taken of the equal number of coils
to make the instrument differential. That is to say, by
using the two sets of coils separately one current may be
sent in one direction and another current in the opposite
direction, so that comparison may be made of their respec-
tive strengths. If both are exactly equal there will be no
deflection, but if one is stronger than the other the spot of
light will travel over the scale and indicate the excess.
By preliminary experiment the direction of deflection by
each current can be determined separately, and in this way
the difference of intensity between the two ascertained.
In experienced hands this galvanometer is as near
perfection as anything made by man can be, but, unlike
those of the moving-coil type, it is directly affected by any
outside vehicle of magnetic or electrical energy. The
near proximity of a steel key or even a steel trousers'
button is sufficient to cause a movement of the light, and
so sensitive is it to induction that it cannot be used
238 STUDIES IN ELECTRO-PHYSIOLOGY:
satisfactorily within three-quarters of a mile of an electric
railway or tube or charging station by reason of the
frequent alteration of load. It is true that, as the human
body is similarly affected, the argument must also apply to
any galvanometer, but in research work one is not always
testing the human body, or dealing with such infinitesimal
electromotive forces and currents.
The cost price of this form of Kelvin is about 30.
We will now consider an instrument of the d'Arsonval
type, which, with equal sensibility, can be bought for
about 10.
Fig. 126.
In this the reflecting mirror does not carry a magnet,
but is directly connected with the coil, which, as will be
seen, is suspended between the poles of two laminated bar-
magnets. At the suspension-head there is a milled pin, by
means of which the suspension may be raised or lowered,
and a movable head which may be turned one way or the
other to adjust the zero. No spirit-levels are provided, but
the instrument may be levelled by placing a small spirit-
level upon the base as shown in the other instrument
and testing it by means of the levelling screws, taking care
that the coil swings freely and is equi-distant between the
ANIMAL AND VEGETABLE 239
poles of the magnets. The cover is then replaced and
clamped on with the screws provided for the purpose.
THE SCALE.
It is clear that a light must be thrown upon the mirror of
the galvanometer and reflected back upon the scale. There
are two ways of doing this. One is to have the direct
light at the back of the scale, thus
Fig. 127.
This is a cheap pattern of scale, but is quite useful for all
purposes where the observer can place himself close to it.
In testing the human body, however, the positions of the
galvanometer, the scale, and the patient in relation to the
observer have to be considered, and it will be evident that
with the patient several feet away from the scale the
observer must be at some disadvantage. To obviate this
difficulty it is better to have a transparent scale (Fig. 128).
It has a mirror upon a universal joint. The lamp faces
the same way as the galvanometer. Its light is thrown
upon the scale, reflected therefrom upon the mirror of the
galvanometer, and thence back to the scale. The height
of the scale is adjustable, and there is a ratchet arrange-
ment to move the scale itself some inches to get a true zero.
240 STUDIES IN ELECTRO-PHYS1OLOGY
idUUlltmiiUUIIMllUllHIIUITU
eLUOTTB03.L01(DOK
ANIMAL AND VEGETABLE
241
In this way, almost irrespective of the position of the
patient, the operator can be within easy reading distance of
the scale.
THE LAMP.
The temptation to have an electric lamp, preferably
affixed to the scale-stand, is great. It offers the advantages
of a brighter spot and less halation, but there is always
the danger of leakage, and for this reason I recommend
a paraffin lamp. A useful type is Fig. 129. There is
a lens, across which there is a vertical wire so
that the spot of light upon the scale appears
as in Fig. 130 ; but it is better, in avoidance of
halation, to paint the lens with dead-black,
leaving only a vertical line J in. wide in the
centre. The spot then appears as in Fig. 131, and can be
more conveniently and accurately read.
THE SHORT-CIRCUIT KEY.
Fig. 132 shows a very useful and reliable
form of short-circuit key, but I have found a
Fig. 131. cheaper pattern answer quite satisfactorily
upon substituting a brass bar for the ebonite one shown
in the front of Fig. 133.
Fig- 130.
Fig. 132. Fig. 133.
SHUNTS.
For research work a shunt in terms of the galvano-
meter, and proportions of J, uV, and ^, is desirable for
use in conjunction with the high-resistance instrument.
242 STUDIES IN ELECTRO-PHYSIOLOGY:
For electro- diagnosis, however, a shunt is unnecessary,
and as the resistance of the coil of a d'Arsonval galvano-
meter seldom exceeds 2,000 ohms, it should not be used
with that type of recording instrument at all. If, however,
it is desired to do so, a " universal " shunt is recommended.
It is a golden rule to " limit the apparatus." To avoid
leakage is to avoid trouble. Let the top of the testing-
table be of teak or other hard wood, and paraffin-wax it.
Also have a gas-fire or electric radiator in the testing-room
and maintain a standard temperature.
CONNECTING WIRES.
To connect the galvanometer with the short-circuit key
and electrodes use the best electric light flex (30 to 40),
untwisting same so as to have single wires.
EARTH CONNECTION.
Thick (preferably insulated) copper wire soldered to
the water-main and the other end brought and connected
to a copper rod or tube in the testing-room, makes a very
good " earth."
THE ELECTRODES.
These are seven in number, and are made for me by
Messrs. Hodges & Co., of St. John Street, Clerkenwell.
For the hand-to-hand deflection I use solid German silver
Fig. 184.
rods (heavily silver-plated), 5 \ in. by f in., provided with
a thumb-piece and a terminal at the upper end (Fig. 134),
the thumb-pieces being shaped as Fig. 135 in plan.
Fig. 135.
ANIMAL AND VEGETABLE 248
German silver has a low co-efficient
of increase of resistance with temperature,
and, when heavily plated, is a very suitable
alloy.
When one of these electrodes is held in each hand by the
patient the thumbs are pushed up to the closed ends of
the thumb-pieces, the fingers used merely in support and
no pressure exercised. The connections are then
Galvanometer
Jflectrcde
tectrode
Fig. 136.
Short-circuit key omitted.
The other electrodes consist of an elastic rubber band, to
encircle the head, carrying a circular plate of silver (or
German silver heavily plated) 1 in. in diameter and
provided with a terminal of the same metal :
Fig. 137.
For purposes of electro- diagnosis this is connected by a wire
to one terminal of the galvanometer, and the band fitted
round the head of the patient in such manner that the flat
244 STUDIES IN ELECTRO-PHYSIOLOGY:
surface of the circular plate makes contact with the centre
of the forehead ; the circuit being completed by means of
another electrode
Fig. 188.
These, preferably, should be three in number ; the
boss, a, having diameters of \ in., T % in. and ^ in. respec-
tively.
The readings obtained, as I explain later on, will be in
conformity with the hand-to-hand deflection and Ohm's
law.
In the galvanometric diagnosis of morbid conditions
the sign of current is of little importance. All the deflec-
tions are comparative. The one thing that matters is the
quantity of current issuing from any part of the body, and
this is shown by the relative rapidity of the excursion of
the light upon the scale ; the gradations being from a very
rapid off-scale deflection in the case of acute local pyrexia
to no deflection at all in cancer.
For diagnosis I recommend the use of a large head-plate,
for the reason that it is imperatively necessary to cover
the central line in order to obtain accurate comparison
between two symmetrical parts of the body, but in research
work, as, for instance, attempting to differentiate efferent
from afferent nerves, sign of current is of the utmost
consequence, and the head-plate must, therefore, be of
exactly the same area and resistance as the electrode used
to complete the circuit.
Formerly I had all these electrodes made of solid silver,
but it involved a quite unnecessary "expense.
ANIMAL AND VEGETABLE 245
CHAPTER XVIII
OHM'S LAW
IN ITS APPLICATION TO THE HUMAN BODY
As I have frequently mentioned Ohm's law, and have
said that all body deflections must conform to it, I will, for
the guidance of the medical practitioner, explain it so far
as may be necessary. I have given it, briefly, as C = ^-
that is, the current at any point is equal to the electro-
motive force divided by the resistances in circuit at that
point, assuming both electromotive force and resistances
to be constant. But that is only a part of Ohm's law, and
we must ponder it further to see whether it in any way
conflicts, or in every way agrees, with observed phenomena.
As most of my readers will be aware, the unit of electro-
motive force is called a volt, that of resistance an ohm, and
that of current an ampere. The quantity of electricity
which flows per second in a current of one ampere is known
as a coulomb, and the capacity of a condenser in which a
charge of one coulomb causes a potential of one volt is
said to be a Farad.
To put it in terms of hydrostatics, with which everyone
will be familiar, E is the head of water (pressure) ; R is
the resistance offered to flow by the inner perimeter of the
pipe (in the inverse ratio to the sectional area of the pipe) ;
C represents the quantity of water flowing through the
pipe at any point, and is, obviously ~ ; while the coulomb
may be said to be the unit of effective discharge,
246 STUDIES IN ELECTRO-PHYSIOLOGY:
Furthermore, the Farad is a unit as, for instance, a
gallon of the capacity of a cistern into which the water
may be caused to flow from E, and in which the quantity
of one coulomb produces a pressure of one volt, by creating,
as it were, another head of water at a lower level.
For a circuit to be established it is necessary in the case
of electricity for there to be a return, either by another wire
or by the earth ; there must be a " loop." Similarly no
water will flow from the cistern unless it has access to air,
nor will any water issue from a pipe unless and until the
tap is opened to air.
The resistance of a metallic conductor is directly pro-
portionate to its length, is in the inverse ratio to its
sectional area, and is expressed by R. There are, however,
resistances (r) other than that of the conductor or conduc-
tors to be taken into account, and the principal of these
(outside the galvanometer and electrodes) is the internal
resistance of the generating cell or cells. This varies not
only with the surface area of the plates but in a galvanic
cell with the chemical composition of the exciting fluid.
Briefly summed up, the E.M.F. is proportional to the
current when the resistance is constant, the E.M.F. is
proportional to the resistance when the current is constant,
and the E.M.F. is proportional to the product of current
strength and resistance when both vary.
The resistance of metals increases with rise of tempera-
ture, while that of liquids and dielectrics decreases more or
less rapidly.
When there are two conductors of different resistance
joining two points, the current in either branch is inversely
as the resistance of that branch.
In reviewing the galvanometric deflections exhibited in
normal health by the human body we must bear in mind
certain facts of primary importance. The conductors
(nerves) and condensers (certain cells) are composed of
ANIMAL AND VEGETABLE 247
moist substances, and their conductivity, instead of their
resistance, increases in a physiologically defined ratio with
rise of temperature, while the electromotive force fluc-
tuates during certain periods of the twenty -four hours and
also in accordance with the degree of fatigue to which the
patient has been subjected. It will be seen, therefore, that
while R may be constant, neither E nor C can be said to be
so. For this, if for no other reason, the hand-to-hand
deflection must be carefully taken. When this is done all
the body deflections must, by Ohm's law, be in conformity
with it.
Another point which calls for consideration is the
capacity of our condenser-ganglion cells and condenser-
compartment muscular fibres. We have seen that a
capacity of one Farad with a quantity of one coulomb
causes a potential of one volt, and the fact that we have to
go into minute fractions of each unit does not affect the law.
The potential at any point (supposing R to be constant)
is liable to variation by any difference in E (producing a
difference in C), while a rise or fall of temperature may not
only alter the resistance of R, generally or locally, but also
the internal resistance (r) of all or some of the cells.
Care, then, must be taken when galvanometric examina-
tions are made to observe the temperature of different parts
of the body, as one part may be colder than another, and by
giving a subnormal deflection introduce error into diag-
nosis. Furthermore, the utmost vigilance must be ob-
served to ensure the conditions of contact being equal, as,
if one part of the skin is more moist than another, the
result, generally speaking, will be a higher deflection from
that part. Inversely the presence of fat in the skin and
subcutaneous tissue would tend to interpose resistance and
therefore diminish the deflection, etc.
We may now proceed with our illustration. When
any amount of resistance is introduced between the
248 STUDIES IN ELECTRO-PHYSIOLOGY:
terminals of a cell, the difference of potential becomes less
than the total E.M.F. observed when the circuit is open.
Assuming the current to consist of a series of polarisations
and discharges, the chemical affinities or contacts must call
up the difference of potential representing the whole E.M.F.
after each discharge. The remaining part of the E.M.F.
is really present in the liquid of the cell, which offers
resistance to the current, and in it the potential follows
exactly the same laws as in the solid part of the circuit.
To illustrate this we will set off a horizontal line ABC
JI
Fig. 139.
and a vertical line AD, representing the E.M.F. AB is
the resistance of the cell (r\ and BC that of the connecting
arc (R). The line DC will then give us the potential at
every point in the circuit.
If there are several cells in compound circuit, AB
represents the total resistance, and AD the total E.M.F.
of the battery. The line of potential will not then be
DC, but a broken line which rises at each cell. Thus,
supposing we have three cells, the line of potential will
be given by EF; GH ; KC. (See above.)
ANIMAL AND VEGETABLE 249
The potential gradient gives us potential differences,
and not the absolute potential at any point. If the cell
and circuit be all insulated, the potential at some parts
will be + and at the other parts , depending upon the
capacity of the various parts of the circuit. If we connect
the circuit with earth at any one point, we have only to
draw a line parallel to the base line through the correspond-
*ng point on the gradient, and perpendiculars to this line
will then give the absolute potential, positive when above
and negative when below this line. The figures drawn
would represent the potential, supposing the zinc plate to
be to earth. (Cummings.)
It is, of course, a matter of Extreme difficulty to apply
Ohm's law to the human body in the absence of more
definite information as to its electrical structure and in
view of the changes which occur, even in normal conditions,
in its E.M.F., capacity, and resistances ; but I am con-
vinced that when the nervous system is studied on electrical
as well as chemical lines and in relation to this law, a great
advance will be made in our knowledge of the human
organism.
HAND-TO-HAND DEFLECTION.
In taking the hand-to-hand deflection several pre.
cautions are necessary
(1) The patient should be placed in contact with an
" earth " of low resistance for five or, preferably, more,
minutes before testing. A copper rod or tube connected
by an insulated wire (with a thick conductor) to the water-
main makes a very good " earth."
(2) Rings must be removed from the fingers, as they
introduce difference of contact ; and all steel, such as keys
and knives, from the pockets, as steel is always more or
less magnetic. Gold, silver, and copper coins do not
matter.
250 STUDIES IN ELECTRO-PHYSIOLOGY:
(3) The hands, after " earthing," must be washed with
soap and water, and not only dried with a towel but given
an interval of at least five minutes before testing.
(4) During the time that the subsequent testing of
the body takes place it is desirable that the number of
persons in the testing-room should be limited to the
patient and the observer. But this is not always possible.
In certain cases a medical attendant and a female friend or
a nurse must be present, but in these cases such persons
should be stationed as far from the patient as possible, and
not admitted to the testing-room until the hand-to-hand
deflection, both as regards sign and quantity, has been
accurately determined.
APPLICATION OF OHM'S LAW TO SOLUTIONS.
Where E = E.M.F., and I is the distance' between
electrodes.
Generally speaking, " the velocity of the ions is pro-
v
portional to the value of the motive force -j ."
Such a law as .that " the velocity with which a particle
moves under the influence of a certain force is proportional
to this force " is valid for all liquid or gaseous particles
moving between other liquid or gaseous particles so long as
collisions constantly take place. This law can be derived
from the principles of the kinetic theory of gases, as is
proved in treatises on internal friction.
" We must imagine the ions as particles of a liquid
which receive an acceleration under the influence of some
external force, electrical or osmotic, and the velocity im-
parted is proportional to the force acting. The ions, like
liquid particles in general, become more mobile as the
temperature rises." (Arrhenius.)
ANIMAL AND VEGETABLE 251
CHAPTER XIX
THE INTERPRETATION OF CERTAIN
ELECTRO-PHYSIOLOGICAL PHENOMENA
THERE are in the human body many structures and
substances which, although not in themselves of very high
resistance, may, in view of the low tension of the nerve-
current, be termed dielectrics. Among these are the
sheaths of medullated and the lipoid coatings of non-
medullated nerves ; the capsules and membranous cover-
ings of and in cells ; the sarcolemma and neurilemma ;
Krause's membranes of voluntary muscular tissue, neu-
roglia processes and connective tissue, etc.
The effect of heat upon any and every known dielectric
is to lower its resistance.
To ascertain, for instance, the relative resistance of
gutta-percha at different temperatures we have the
formula
Log R = log r t log 0-9399
where R = resistance at higher temperature,
r resistance at lower temperature, and
/ = difference in temperature in degrees F.
Reduced to figures, the relative resistances, calculated
from the curve, are : 75 F. = 1-000 ; 90 F. = 0-407;
100 F. = 0-223 ; 110 F. = 0-137.
In acute inflammation the local temperature that is,
the temperature in the area affected may rise at least ten
degrees F. above normal ; and this would, for gutta-
percha, give us 0-4068 (at 90 F.) and 0-2238 (at 100 F.),
252 STUDIES IN ELECTRO-PHYSIOLOGY:
or a fall of nearly fifty per cent, of resistance, or (roughly)
five per cent, per degree.
Inasmuch as the human nerve-current escapes through
the dielectrics of the body, despite the fact that the tension
is not more than from 4 to 5 millivolts, it is evident that
their resistance is infinitely lower than that of gutta-
percha.
We have no means of determining with accuracy the
resistance of any of these dielectric structures or substances
in their natural and normal environment, nor, while we
know that a rise of temperature affects them adversely,
must we at once assume that the relative fall in resistance
of a nerve-sheath is the same as that of gutta-percha.
Maxwell's recent experiments, however, went to show that
a rise of 10 C. approximately doubled the velocity of
nerve-conduction by lowering the resistance of the nerve-
substance.
Heat decreases the resistance of liquid and increases the
resistance of metallic conductors in a known ratio. Com-
paring a nerve with a copper wire, the increase in resistance
of copper per 10 F. would be one-fifth or twenty per cent.
=to two per cent, per degree, but the fall in resistance of
gutta-percha due to the same increase is nearly fifty per
cent. By this process of reasoning we find some ground
for the belief that the effect of temperature upon the
dielectrics of the body is approximately the same as upon
gutta-percha ; involving roughly a fall of five per cent,
per degree Fahrenheit within certain limits, although I
believe the loss to be much greater.
Now, it is quite obvious that if the organs of the body
connected with the transmission of impulses, the mainte-
nance of neuro- electrical equilibrium, the conservation of
energy, and the contraction of muscular tissue are to
function properly, the temperature of every part of the
whole organism must not exceed the normal, which we may
ANIMAL AND VEGETABLE
253
take to be, subcutaneously, about 100 F. Protoplasm
dies, I am informed, at about 114 F., and as we know
that cells do die in the area affected by acute inflammation,
we have a right to postulate that, in that area, there may
be a rise of temperature of at least 10 F. above the normal.
And with what result ?
Suppose a submarine telegraph cable to connect two
stations, A and B, and the battery at the sending station,
A, to have just sufficient E.M.F. to overcome the resistance
and allow for the leakage of 'the cable and actuate the
receiving instrument at B. What would happen if at some
point intermediate between A and B the dielectric the
gutta-percha of the cable became heated to 110 F. ?
There would be a loss of fifty per cent, of its insulation, an
escape to earth at the fault and interrupted or faulty
communication with B. The following diagrams will make
this clear, assuming the leak to be equidistant between
A and B
Jfcrmarf Condilton
Fig. 141.
I
Abnormal Condition
Fig. 142.
That, approximately, is what occurs when the resistance
of, say, a nerve-sheath, or the coating of a non-medullated
nerve, is partly broken down by the rise of temperature
254 STUDIES IN ELECTRO-PHYSIOLOGY:
incidental to inflammation, and as a consequence the
nervous impulse or current is not conveyed at normal
pressure to its destination, to supply blood-vessels, to
actuate muscular fibres, or to energise or transmit messages
to various cell-groups.
Nor is this the full extent of the mischief. The current
escaping through the fault, in conformity with natural
laws, seeks the path of least resistance to earth (air), and
from that point throughout that path the cells are in a
highly electrified area, and, their insulation not being
capable of withstanding the strain, they in all probability
become over-ionised. A condition is thus created favour-
able to the multiplication of inimical bacteria and
unfavourable to phagocytosis.
The path of least resistance must be from the fault
through the intervening tissues and the skin, to air, and
generally, it will be the shortest path. But wherever it is
it is clear that an abnormal quantity of current must issue
from that part of the skin in which the " path " terminates,
and that if we place the circular plate upon the centre of
the forehead of the patient in order to be sure of getting
on the central line, and another electrode upon the affected
area both electrodes being, of course, connected to the
galvanometer the fault will manifest itself by a more or
less rapid excursion of the light upon the scale ; that is to
say, the rapidity of the excursion will be proportionate to
the quantity of neuro-electricity escaping, and that quan-
tity will also be proportionate to the rise of local tempera-
ture or to the degree in which local insulation resistance
has been broken down by temperature.
Let us, for example, take a case of lobar pneumonia,
the base of the right lung being affected (Fig. 143).
Here, after taking the hand-to-hand deflection, we are
able to make intelligent comparison of the galvanometric
readings from the affected and the unaffected lung, or at
ANIMAL AND VEGETABLE 255
all events from two symmetrical parts of the chest and back.
Whatever the hand reaction was the body deflections
would all be lower, because of the resistance interposed not
to Ga.lvct nomcler
8O m /mstou>
leftfas*.
* I v i \ 9^.
4--|^j.-'>V-'
Fig. 143.
only by nerve-substance but by sebaceous glands and fat
cells, and in no case would the light, under normal con-
ditions, exhibit a rapid movement upon the scale. In the
above illustration we have obtained deflections of 80 mm.
slow upon the unaffected, and 250 mm. rapid upon the
affected side, and have found the rate of travel increase as
the electrode touched the skin on the centre of the spot of
44 least resistance." That would, with a galvanometer of
the sensibility I have described, postulate semi-acute
inflammation and indicate a fairly high local temperature,
but in a very acute case the light would be seen to fly off
the scale.
In double pneumonia there would be a short-circuit
between the two lungs, or the affected parts of them, and
the path of least resistance, common to both lungs, might
be from the left lung or the right, to the skin.
These remarks apply to galvanometric observation of
all forms of local pyrexia. As regards the exact internal
^position of the fault, the deflections should, theoretically,
256 STUDIES IN ELECTRO-PHYSIOLOGY:
be the same from the back and front when the "fault" is
equidistant, higher from the front when it is nearer to the
front, and higher at the back when it is nearer to the back,
but in practice the conditions of contact must be studied
and allowance made for them. As a rule, the skin of the
back is more oily or greasy than that of the chest. A little
experience, however, will enable the physician to make
correct diagnosis.
In order to make clear much of that which in physiology
remains obscure it is only necessary to reason in terms of
highest potential of nerve-force in the brain and
differences of potential in the body, or, to put it another
way, in terms of hydrostatics ; the brain being the con-
stantly maintained head of water, the nerves the motor
and secretory paths the pipes through which it flows, and
differences of potential being differences of level.
The sensory nerves may be compared with pipes filled
with water at an adjusted pressure, and the impulses
conveyed by them to the brain to the undulations or
vibrations transmitted through them by reason of any
disturbance of that adjustment.
Thinking along those lines, we may more intelligently
conceive how and why it is that local pyrexia manifests
itself, electro-pathologically, as an expression of greater
quantity of nerve-current in the part affected. It is an
expression of lower level, because the resistance of the path
is lowered. Normally the resistance, if we consider it as
level, would be represented by the line ab in the following
diagram :
Fig. 143x.
The head of water the vertical line au remains unaltered
ANIMAL AND VEGETABLE
throughout, but owing to local pyrexia at b the level is
altered and the diagonal may become
-.air
Fig. 143 B .
giving the effect of increased pressure and consequent
greater flow.
Not only is this so, but as a local rise of temperature
lowers the level of issue, it, at the same time, enlarges the
diameter of the pipe, in the area affected, by increasing the
conductivity of the moist conductor, the nerve-substance ;
so that we have not only a lower level, but what may be
likened to an artificial head of water created in the path a, b.
Similarly alterations of resistance in the form of added
resistance due to disease may be thought out. Between
acute local pyrexia, such as lobar pneumonia with a body
temperature of 106 F. involving, possibly, a local
temperature of 116 F. and cancer, there would be the
widest margin, because the cancer cells are devoid of
conductivity. In the latter case our diagram might
become
..atr
Fig. 143c.
and there would not be any flow at all from a to b.
There are many gradations between the two extremes,
but after due allowance has been made for skin conditions,
3
258 STUDIES IN ELECTRO-PHYSIOLOGY:
sebaceous glands, and so forth, it will be found that
differences of resistance imply differences of level, and that
those differences, as shown hy the galvanometer, may,
with care, guide the way to correct diagnosis.
Some physiologists have endeavoured to explain wide
deflectional differences as being due to varying conditions
of contact, that is to say, to the presence of more or less
moisture in the skin. But in pyrexia, local or otherwise,
moisture is conspicuous rather by its absence than its
presence, and it will be found that a hot, dry skin will,
when it is associated with inflammation, always give a
higher deflection than is obtainable from any part of the
body not so affected.
In febrile diseases it is generally the first care of the
physician to get the skin to act.
Moreover, experience has shown that in a number of
cases of nervous asthenia the hand-to-hand deflections,
despite the fact that the palms were wet, were all low
(40 or 50 mm.) and all negative, reverting only to the
positive side of the scale upon convalescence.
IMPAIRED CONDUCTIVITY.
A converse condition is when there is a partial failure
of inter-cellular conduction, due either to increased resist-
ance of the nerve-substance or to some change in the ionic
cell contents by which they are rendered less active. It
very frequently happens that a painful disorder is diagnosed
as neuritis or sciatica and that treatment gives no relief.
True neuritis, as I understand it, is an inflammatory
condition, caused by the insulation resistance of a sheath
of nerve or nerves being interfered with by local pyrexia.
In my experience the neuritis we hear so much about is
sometimes not so. It is, perhaps, in five cases out of ten,
due to some toxin. Pyorrhcea, the internal administration
of nux vomica, post-diphtheritic poisoning, inoculation by
ANIMAL AND VEGETABLE 259
certain sera, and chill are direct causes, and in every case
the affected part will yield a subnormal deflection,
indicating treatment by ionic medication.
VARIOUS FAULTS.
When there is any functional throat trouble, asthma,
or irregular action of the heart, the vagus nerves should
always be tested by placing a small electrode (J in. boss)
directly below and a little forward of the angles of the jaw ;
while " nervous breakdowns," excessive nervousness,
insomnia, and some uncertainty of movement may have
their origin in spinal faults which can be readily detected.
I remember one case of supposed epilepsy (grand-mal)
in the patient of a medical friend. The pulse was 40,
the eyes lack-lustre, and fits (so-called) were of frequent
occurrence. Galvanometric examination revealed a line
of chronic inflammation extending from the base of the
cerebellum to the right cervical . Under diel ectric treatment
the pulse went from 40 to 70 in a fortnight, his
health became normal, and he has since been able to pursue
his avocations. His trouble was that when the inflamma-
tion became acute as it did from time to time and the
quantity of nerve-current escaping became excessive, he
fainted.
I mention this merely to emphasise the importance of
the galvanometer in obscure morbid pathology.
Reverting for a moment to the vagi, it must be borne
in mind that they have both efferent and afferent branches,
and that when they or one of them exhibit a high and
intermittent both positive and negative deflection, it
inferentially argues intermittent contact between those
branches. The afferent branch is sensory but the efferent
is not ; the escape, therefore, from the sensory branch
might be constant and that from the efferent only active
when the nerve conveyed an impulse.
260 STUDIES IN ELECTRO-PHYSIOLOGY:
ON DISEASE IN GENERAL.
In connection with electro-diagnosis I have postulated,
both verbally and in print, that any physical change in the
body must be attended by a neuro- electrical change, which
can only be galvanometrically detected ; and that the
process of restoring the one to normality tends, automatic-
ally, in the great majority of disorders, to restore the
other to normality.
Disease is a deviation from the state of health, implying
some alteration in the functions, properties, or structure of
some organ or tissue, and may be generally described as
an abnormal performance of the processes constituting
life. That being so, it would be illogical to imagine that
one of the most delicate and most necessary of those
processes, i.e., the maintenance and regulation of the
neuro- electrical system, could proceed without deviation in
any diseased area.
GALVANOMETRIC TESTS OF OTHER DISEASES.
NEURASTHENIA.
To my mind a knowledge of the electro-pathology of
this disease is of vital importance to humanity, as, so far,
it is imperfectly understood and, therefore, imperfectly
dealt with. Neurasthenia, of course, means nervous
weakness, but viewed from an electro-pathological stand-
point it has a characteristic which differentiates it from
any other irregularity of the nervous system with which I
am acquainted, and which I believe to be peculiar to a new
disease. It certainly has one feature in common with
nervous weakness, and that is a deficiency of nerve-
energy ; but while asthenia exhibits a low hand-to-hand
deflection, it is constant, whereas the neurasthenic deflec-
tion is so variable as to sign of current that the light is
never at rest. It may be anything from 5 to 90 mm. or
so, but will be both positive and negative, moving slowly
and erratically backwards and forwards, from one side of
ANIMAL AND VEGETABLE 261
zero to the other, never becoming constant or giving any
definite indication of the normal electrical sign of the
patient. This irregularity, this fluctuation, combined with
an insufficiency of nerve energy, is a peculiarity of neuras-
thenia, distinguishing it from other nervous affections.
The behaviour of the sufferer from this disorder is, as
a rule, consistent with the galvanometric reading. There
is a corresponding fluctuation of will. Victims to neuras-
thenia are slow to admit to others that there is anything
wrong with them, and if treated will not long submit to
the same treatment, but go from doctor to doctor, or try
a few doses of every quack medicine they see. They never
seem to know their own minds for many minutes together,
and in this respect their mental and neuro-electrical
symptoms appear to be in accord. They may, reasonably,
be termed neurotic, but this is perhaps a misnomer. The
fault, theoretically, can be said to be partly due to intermit-
tent contact between efferent and afferent centres and
consequent disturbance of neuro-electrical equilibrium, in-
volving defective distribution of nerve-energy.
EPILEPSY.
It follows, as a matter of course, that anyone engaged in
electro-pathological research would bestow a maximum of
attention upon this awful scourge of humanity, and I have
been fortunate enough to have had many opportunities of
studying it. My observations, however, are strictly con-
fined to the neuro-electrical problem presented by the
disorder, and even from this comparatively narrow point
of view it exhibits so many complex features that I am quite
at a loss for a well-grounded opinion of its origin, or of the
predisposing cause or causes. I know what happens, but
how or why it happens is hidden from me, though it will
certainly be revealed to some other student. In this
connection it is my earnest hope that such data as I am able
to offer may prove to be of value.
262 STUDIES IN ELECTRO-PHYSIOLOGY:
The principal neuro- electrical phenomena common to
grand-mal are low body deflections, combined with sub-
normal body temperature, excessively high head deflec-
tions and temperature, and a point of least resistance at
some part of the skull, from which, during an aura or during
and directly after a fit, an abnormally high deflection is
obtained.
The direct cause of the fit is, in fact, a species of neuro-
electrical brain-storm, and this storm is unquestionably
due to the nerve-force supplied to the brain not being able
to find its proper outlets or channels from the brain to the
nervous system the afferent nerves, conductive from
without but not receptive from within, possibly adding to
the pressure with the inevitable consequence that the
pressure in the brain becomes unbearable, and produces a
fit. Were this pressure not relieved, death or insanity
would probably ensue, but Nature provides for this con-
tingency by creating in the skull a path of least resistance
to the passage of the pent-up current to air. The exact
spot must be tested for and located in each case, and it is
from this spot a safety-valve that the highest head
deflection is obtained.
Too much importance can hardty be attached to the
existence of this " safety-valve," because it not only points
to a means of alleviation, but affords convincing proof of
the soundness of the theory I have advanced.
If the hair covering the " safety-valve " is shaved off
and a small silver plate is fastened upon it (the valve) by
means, say, of adhesive plaster, and an elastic belt carrying
a circular metallic plate, provided with a terminal, is placed
round the waist in such manner that the body-plate makes
contact with the skin, preferably 2 in. above the navel, it
is only necessary to connect the two plates by a wire a
shunt-circuit to bring in a few minutes- the head and body
deflections and temperatures to normal,
ANIMAL AND VEGETABLE 268
There is at least one other proof. If the patient is
watched and an aura detected, no fit will ensue if the head
is at once wetted with warm salt water, to lower the
resistance of the scalp and create an artificial path to air for
the congested nerve-force.
Whatever the cure may eventually prove to be, it must,
as one of the curative measures, have the effect of pre-
venting the brain from becoming neuro- electrically con-
gested and the body neuro- electrically starved. It has
only recently been suggested to me by Dr. E. W. Martin,
and I have, had no opportunity of putting the hypothesis
to the test, that a careful galvanometric examination of the
spinal cord may disclose such high resistance in some
anterior part of it as to suggest a temporary break of
continuity. If that feature is exhibited in a number of
cases it will be worth while to try to remedy the condition
i.e., restore conductivity by local ionic medication.
That is a matter for further research and experiment. In
the meantime no one suspected of a tendency to epilepsy
should be permitted the use of hair pomades or oils, or,
above all, of peroxide of hydrogen.
As a final word upon this subject I should like to
express my opinion of the therapeutic value of the bromides
of potassium and ammonium. They act by checking the
generation of nerve-force in much the same way that
they act in photography. They check development
and especially mental development and between a
choice of two evils I do not know which is to be preferred ;
bromide saves trouble to others, at the expense of the
patient.
CANCER.
Notwithstanding the fact that many hundreds of the
most notable men of their day have devoted and are
devoting their lives to the study of cancer, it is unfortu-
nately true that the/on^ et origo of the disease still remain
264 STUDIES IN ELECTRO-PHYSIOLOGY
in obscurity. Cancer has yielded nothing to bacteriological
research. Surgery cannot claim that the knife is an
infallible cure, because the surgeon can never be sure that
he has removed the entire growth ; electro-cautery has
proved to be merely useful, and medicine has not been
able to provide more than temporary relief from pain.
From galvanometric research also nothing decisive has been
learned, but I am encouraged to think that this is because
the opportunities of observation and study have been too
few in number, and that the little we have gained will at
all events stimulate other workers to renewed investiga-
tion upon the lines I have ventured to lay down.
Of cases of suspected cancer I have tested many, but of
cancer certified to by high medical authority not more than
half a dozen. This, it may be thought, does not warrant
me in coming to any definite conclusion as to the electro-
pathology of this disease, but if I disagree it is because in
all those six cases not only did I find the cancer cells to be
non-conducting, but my observations have been borne out
by others.
From a cancerous growth, more especially if it is not
deep-seated, no deflection whatever will be obtained,
even if the skin be moistened, although the secondary
deposits may exhibit lines of acute inflammation. The
only means of alleviation or cure suggested by galvano-
metric research do not, so far, go beyond restoring con-
ductivity to the deionised cells by suitable ionic medication,
but the galvanometer should provide valuable assistance
to the operating surgeon by enabling an accurate diagram
of the whole of the affected area to be drawn upon the skin.
The disease, as we know, frequently recurs because com-
plete excision has not been made.
APPENDIX
APPENDIX 26T
ELECTRICAL CONDITIONS OF THE EARTH
IN the first section of this work I have said that in
countries free from magnetic and seismic disturbances and
in ordinary conditions of weather the earth is the negative
terminal of Nature's electrical system. That is a state-
ment of fact, but modernity has, in some of the large towns
of the world, introduced a new factor in a multiplicity of
electrical railways and "tubes," and this factor must be
considered in relation to the accepted theory that, as
compared with all other electrical tensions, the earth is
regarded as zero.
In body-testing it is necessary that it should be,
approximately, so. There must always be a transfer
from a plus to a minus quantity w r hen there is direct
conduction. If the transfer is made inductively then the
problem becomes one of tension and spark-gap.
In electro- diagnosis and body-testing generally the
patient must be connected for some minutes with an
" earth " of low resistance in order to remove any possi-
bility of charge from a source of energy other than that of
the body itself, and if this is to be accomplished it follows
that the tension of the body must be plus and that of the
earth minus, otherwise there would be a transfer of elec-
tricity from the earth to the body instead of from the body
to the earth.
In certain localities, and in abnormal conditions of
weather in other localities, the earth may become very
highly charged, and unless this is taken into account results
may be obtained in testing which will perplex the observer,
268 APPENDIX
In order to illustrate my meaning we may usefully
ponder earth conditions during a thunderstorm, in relation
to contour and nature and conductivity of soil.
Let us disregard for the moment the terms positive and
negative and substitute for them the words " plus " and
" minus."
The air, the upper stratum and, hypothetically, stretch-
ing upwards to infinity, is always " plus " ; the earth,
normally, " minus."
Between the charged cloud and the comparatively
uncharged earth there is an air-space the spark-gap and
unless the tension of the cloud is sufficiently high to bridge
it no discharge can take place. Suppose the surface of
the earth to be flat
Zartk
Fig. 144.
or, alternatively, the surface to be very dry or composed of
some more or less dielectric material. The cloud would
unless the tension were extraordinarily high travel over
Fig. 145.
such ground without discharging. When, however, by
reason of contour, the distance between earth and cloud
was lessened to one that the tension of the cloud could
APPENDIX
overcome, or, alternatively, tension being sufficient, a
point was reached where the soil favoured conduction, a
transfer of potential from the plus cloud to the minus earth
would at once take place, in exactly the same manner that
a spark is obtained from a Ley den jar or induction coil when
the conducting knobs or points are approached near
enough to each other. Scientifically this is termed a
disruptive discharge. It occurs when the air becomes
strongly strained by the potential difference, and, suddenly
yielding, allows the discharge to pass, not freely as through
a conductor, but by a violent disturbance of the molecules
of air along the path, which become strongly heated, and
make the visible spark. This takes a zigzag and forked
path which in all probability is the line of least resistance,
and is due to irregular distribution of conducting motes in
the air, or to its hygrometrical condition.
However this may be, we will imagine that at the point
A (Fig. 1 46) the sub-soil is of such a nature that the charge
which it has just received from the cloud cannot be readily
dissipated, and that another cloud which has discharged
itself in the immediate vicinity passes over it within a
distance over which the spark-gap can be bridged. The
Jfartk
result must be that discharge will take place from earth to
cloud, because the cloud is the minus and the earth the
plus quantity ; but it does not necessarily follow that such
discharge must be from the exact area which first received
270 APPENDIX
it ; it is only required that the plus and minus quantities
should be earth and cloud respectively.
In the same way the human body is liable to be in-
fluenced not only by being placed in an earth circuit but by
induction ; its normal electromotive force of four or five
millivolts can only be a plus quantity in favourable
circumstances.
In reviewing the electrical phenomena consequent upon
the operation of such a system as the District Rail way, we
may read for electrified clouds the effect upon the air of
alterations of load, while the iron-clad tubes with their far
from perfect insulation must be responsible for artificial
earth- currents of such potential as to seriously interfere,
over a very considerable area, with electro-diagnosis.
Similarly in tramway lines where direct current is
employed the overhead system is likely to affect the air
locally, and the conduit system to charge the earth, although
the range of inductive interference is not nearly so great as
in the case of railways and tubes.
Quite apart from these artificial disturbances, the
hypothesis that in an electrical sense the earth is zero
should not be too readily accepted. Prior to important
experiment an " earth " should be tested galvanometrically,
and although in certain localities the test may be dispensed
with in ordinary work, it is a precaution to be recom-
mended.
As a matter of fact the earth is electrically " patchy,"
the potential and direction of current varying, greatly in
different parts of the world. Darwin found the neighbour-
hood of the Rio Plata to be peculiarly subject to electrical
phenomena and was inclined to suspect that thunder-
storms were very common near the mouths of great rivers.*
On the East African coast the earth-current has remained
at about forty volts for many weeks in succession. At that
* Journal of Researches.
APPENDIX 271
time I was stationed at Delagoa Bay, where the English,
Tembe", Umvelosi, and other rivers debouch. Thunder-
storms during the rainy season were of very frequent
occurrence. Durban, some 360 miles south, is situate at
the mouth of the Umgeni river, and in the same season is
visited by a thunderstorm almost every afternoon at about
the same hour. We are aware that such storms occur most
frequently within the tropics and diminish in frequency
towards the poles, during day rather than night, after
midday than before it, and in mountainous countries than
in plains, but we have no definite knowledge of the causes
which set up and set in motion the forces known to us as
natural earth-currents.
Flammarion attributes the aurora borealis, which
sometimes illumines the darkness of night in the Arctic
and other regions of the North, to the striking of a balance,
silent and invisible, between two opposing tensions of
the atmosphere and the earth ; thus the apparition of the
aurora borealis in Sweden or Norway is accompanied by
electric currents moving through the earth to a distance
sufficiently great to cause the magnetic needle to record the
occurrence in the Paris Observatory .
Indeed, the electricity which pervades the earth is
identical with that which moves in the heights of the
enveloping atmosphere, and whether it is positive or
negative its essential unity remains the same, these
qualities serving only to indicate a point, more or less in
common, between the different charges. The heights of
the atmosphere are more powerfully electrified than the
surface of the globe, and the degree of electricity increases
in the atmosphere with the distance from the earth.
Atmospheric electricity undergoes, like warmth, and
like atmospheric pressure, a double fluctuation, yearly and
daily, as well as accidental fluctuations more considerable
than the daily ones. The maximum comes between six
272 APPENDIX
and seven in the morning in summer, and between ten and
twelve in winter ; the minimum comes between five and six
in the afternoon in summer, and about three in the after-
noon in winter. There is a second maximum at sunset,
followed by a diminution during the night until sunrise.
(Flammarion, 1905.)
Fulminic matter, remarks the same author, is strongly
attracted towards damp regions, and is guided on its way
to the earth by the hygrometrical conditions of the atmo-
sphere. Violet lightning is thought to come from the
upper stratum of the atmosphere, and a flash has been
found to have a maximum length, as observed from the
earth, of over eleven miles.
That earth-currents have, at times, an origin which is
in part thermal seems not unlikely. Earthquakes are of
common occurrence in the tropics, and I remember two
on the East Coast of Africa. One made a difference of
750 fathoms in the soundings off Mozambique, and the
other was experienced at Delagoa Bay much about the
time that the earth-current rose to forty volts. It is a
curious fact, though probably only a coincidence, that the
submarine upheaval off Mozambique, the earthquake at
Delagoa Bay, and the forty-volt earth-current before
mentioned took the same course, i.e., north and south.
Dutton records an instance of an earthquake at the
Yaqui river which disturbed the needle of the magneto-
graph at Los Angeles, a distance of more than six hundred
miles, and it is possible that forces which in themselves
are insufficient to cause even a slight convulsion of Nature
may be responsible for the creation of high potential at one
point, whence it is distributed to another point or points of
lower potential ; the precise path being governed by electro,
lytes in the earth, or, in other words, by the same law which
directs the course of lightning through the atmosphere.
In speaking of earthquakes we must, of course,
APPENDIX 278
differentiate between those which are caused by sub-
sidences and those of volcanic origin. Volcanoes are not
confined to any one part of the world, but are to be found,
so far as latitude is concerned, pretty nearly everywhere; in
the Arctic Ocean, in the volcanic island of Jan Mayen,
between Iceland and Spitzbergen ; there are Mount
Erebus and Mount Terror in the Antarctic, besides very
numerous volcanoes in the Atlantic, Pacific, and Indian
Oceans, and their shores in both the temperate and torrid
zones. In all they are said to number, in a state of activity,
some three hundred. " Of these about two hundred and
fifty lie either on the borders of the Pacific, or on some of
its many islands. Thirty-nine either lie within or on the
borders of the Atlantic, of which thirteen are in Iceland,
or near the Arctic Circle, three in the Canaries, seven in the
Mediterranean Sea, six in the Lesser Antilles, and ten in
the Atlantic Ocean Islands. There are, however, a much
greater number of extinct volcanoes, which may at any
time again become active." (Houston, 1908.)
The difficulty we are faced with is conveyed in the last
paragraph. Were it not for the uncertain number and
condition of extinct volcanoes, or rather of volcanoes
which have ceased for the time being to give any mani-
festation of activity, we might consider earth- currents in
their possible relation to areas liable to thermal dis-
turbances with a view to determining whether any con-
nection between them is suggested by their coincidence.
One fact stands out prominently : thunderstorms
diminish in frequency towards the poles, and if they are a
factor in determining the occurrence and strength of earth-
currents of unusual tension one would expect to find a
minimum of disturbance towards the poles. I happen to
know, however, that in the neighbourhood of Port Arthur
a region admittedly volcanic the earth-current some-
times attains a potential of 500 volts.
T
274 APPENDIX
In the early part of this Appendix I have spoken of a
dry or more or less dielectric earth-surface, and we may
usefully consider what its effect may be upon health.
The electrical condition beneficial to plant life is soil
conductivity. If the soil is not moist to the root-depth the
plant is deprived of its supply of current, and must^ suffer
injury.
Dry earth, if not a non-conductor of electricity of high
tension, is at least a very bad conductor, as are certain
clay and rock formations. With such an upper stratum
there could be no normal circuit. In that area the earth-
terminal would be insulated, and the air, I should imagine,
abnormally charged by reason of the absence of a low
resistance path to earth. It would be interesting to have
some information upon the subject of the health of persons
residing in these localities and the bearing of climatic
conditions of the kind upon specified diseases.
At the same time, data as to the influence upon man and
plant of ferruginous soils should be useful if only for
purposes of comparison ; I say ferruginous, because with
iron as the electrolyte it is possible to have dry air and
earth and, at the same time, good earth-conductivity,
whereas in swampy districts there would, quite apart from
miasma, etc., be a damp atmosphere and therefore a
totally different environment.
In the analysis of climate in its relation to disease many
painstaking investigators have confined themselves to
pondering characteristics of the atmosphere, and with
those we have no present concern, except in so far as they
may be affected by the electrical receptivity or otherwise
of the earth. It is true that dust from dry soil may
contain the germs of infectious diseases and aggravate
affections of the respiratory organs, but, difficult as it is,
I want to ascertain the effect of a non-conductive as
opposed to a conductive dry soil upon certain specified
APPENDIX 275
diseases. In the tropics death-rates are high, but bad
sanitary conditions and lack of medical attendance account
to some extent for mortality among the natives, while an
irrational mode of life explains many deaths among persons
coming from cooler climates. Generally speaking, malarial
and yellow fever are only endemic on coasts and in the
neighbourhood of waterways, and only then when the air
temperature is 75 F. or over and the earth sodden. In
such case there would be an upper earth-stratum of un-
usually low resistance, and the air-charge might be at its
minimum, with consequent loss of part of its value as a
vitalising agent. Stations more than a few hundred or
thousand feet above the sea-level are free from yellow
fever, probably because of their lower temperatures
increased earth-resistance, and higher air-potential.
Yellow fever has only very rarely occurred at an altitude
of 4,000 ft. above sea-level, and the same remarks appear
to apply to dysentery and diarrhceal disorders, as well as to
many other diseases of which the predisposing cause is
lowered vitality.
Dengue fever is distinctly a disease of warm climates,
and is always checked by cold weather ; it follows coast-
lines, deltas, and large river-valleys. In beri-beri high
temperature and dampness are controlling factors, as is the
case in sleeping sickness and yaws. In the tropics " the
drier districts are to be preferred to the moister, the higher
altitudes to the lowlands." (Ward, 1908.)
Temperate zones may be said to be intermediate
between the equatorial and polar zones. Here we have
variations of temperature and moisture which, so far as
their influence upon health is concerned, are beyond our
purview, inasmuch as there are many conflicting theories
and no really conclusive evidence, apart from the broad
fact that in tuberculosis and other and similar diseases
the dry, pure air and abundant sunshine of many of the
276 APPENDIX
well-known mountain resorts are very favourable climatic
helps. In this connection, however, one cannot tell how
far purity of air, hygienic surroundings, and a suitable
dietary may counteract upon an unfavourable earth
condition. We can only be sure that a lowered vitality
not only predisposes to disease but operates against its
cure.
In the polar regions larger temperature ranges can be
endured in the winter, when the air is dry. In severe cold
the vitality of the body is lowered and the ability to bear
hardships decreased. But here, again, the body is acted
upon directly by cold. The resistance of the natural (semi-
liquid) conductors is increased, the blood circulates more
slowly, the surface blood-vessels contract, and only an
added skin-resistance, by helping to conserve energy,
prevents the heart and lungs from becoming dangerously
affected. Eskimos are protected against the cold by their
thick, fatty tissues, which give them high absolute-
insulation.
It is a complex subject. " Diseases usually charac-
teristic of one zone are known to spread widely over other
zones. Diseases which usually prefer the warmer months
sometimes occur in the coldest. Rules, previously deter-
mined as the result of careful investigation, often break
down in the most perplexing way. Some of the difficulty
in this lack of agreement results from untrustworthy
statistics, often collected under varying conditions and
really not comparable. Curves are smoothed to such an
extent that they can be made to show anything. Con-
clusions are drawn in individual cases which are neither of
general application, nor do they even apply locally on any
other occasion than the special one in question. Most of
this disagreement comes from the fact that not only may
the different weather elements themselves, temperature,
moisture, wind, sunshine, and so on, each have some
APPENDIX 277
effect in the production of a disease which it is impossible
to determine, but so many factors are concerned in the
matter that confusion and contradiction in the conclusions
reached are inevitable." (Ward, 1908.)
All this is very interesting and true, but it does not
answer my question as to the relative effect, if any, of
non-conducting and conducting soils other things being
equal upon certain specified diseases, and I am afraid that,
so far, nothing of value upon this subject has been pub-
lished, probably not even recorded.
This much, however, is known to a few submarine
cable electricians. A simultaneous observation taken at
eighteen stations in 1912, and my own results during this
year, gave the maximum earth-current as eight volts, and
this can, in all probability, be accepted as the normal maxi-
mum, for fairly short cables, in the absence of magnetic
disturbances. Long cables, on the other hand, not infre-
quently exhibit currents of comparatively high tension,
and this may be explained by the greater area traversed
by them.
ELECTRICITY IN RELATION TO SOME
VEGETABLE POISONS.
\
I have read recently of persons being poisoned by
rhubarb leaves, boiled and eaten as a vegetable. My
research work has taught me what to avoid in vegetarian
diet, although I am not a vegetarian, and we my
people and I have enjoyed rhubarb leaves for years.
They are, however, always more or less aperient, and
should be eaten in moderation.
The subject of vegetable-poisoning in relation to
dietary and habit is one of interest and importance, and I
am glad to be able to throw some light upon it.
All vegetable toxins, so far as my experiments have
278 APPENDIX
gone, yield a negative galvanometric reaction. The
negative system of a plant is in the root, stem, stalks, and
veins of the leaves. The older the leaves are and as a
rule they are those nearest the soil the larger the veins.
This argues lower internal resistance, and therefore more
current, with, as I have found, greater toxic activity. In
all probability only the areolse of the leaves approach
chemical neutrality.
As instances of this we may take the tobacco and tea
plants. In the former the lower leaves are coarse- veined,
and contain so much essential oil as to be fit only for the
manufacture of insecticides, while everyone knows that,
given any description of tea, the choicest of it will be the
young tips and flowers, owing mainly to their comparative
freedom from tannic acid.
The stalk and veins of the leaves of many plants and
vegetables are, no doubt, harmless, but even when Nature
does not render them unpalatable instinct teaches us to
rej ect them. If the stalks of the cabbage are not unpleasant
of taste they are hard and somewhat fibrous ; so, too, the
core of the apple, the white negative substance in the
orange, and the root of the lettuce, are bitter, and so on,
through a wide range of the vegetable tribes.
I have no information upon the subject, but venture to
express the opinion that vegetable poisons will be found
only in those parts of a plant which yield a negative
galvanometric deflection.
In any case it should be of advantage to remove the
larger veins by excision from all leaves used for food. The
difference in flavour is very marked when this is done, and
will more than repay the trouble taken.
A simple experiment will demonstrate this very
effectively. Take, say, J Ib. of any kind of tea. From
2 oz. of this pick out and throw away all the loose stalks,
of which there are generally many. Then prepare an
APPENDIX 279
infusion from each sample and compare. In the same
way whole leaves of tobacco may be treated by cutting
away as far as possible all the veins, and the residue smoked
in a pipe. This will be pronounced infinitely superior to
the crumpled untreated leaf.
280 BIBLIOGRAPHY
BIBLIOGRAPHY
Physiology of Plants : SACHS.
Text-book of Biology : DAVIS.
Vegetable Physiology : CARPENTER.
Physiology of Plants : DARWIN AND ACTON.
Microscopic Fungi : COOKE.
Structural and Physiological Botany : THOME.
Plant Life and Structure : DENNERT.
Evolution of Plant Life : MAS SEE.
Agricultural Botany : POTTER.
The Evolution of Plants : SCOTT.
Plant Life on Land : BOWER.
Handbook of Plant Form : CLARK.
Text-book of Botany : VINES.
Vegetable Physiology : GREEN.
Text-book of Botany ; STRASBURGER AND OTHERS.
Chemistry of Plant and Animal Life : SNYDER.
The Vegetable World : FIGUIER.
Botanical Text-book : GRAY.
The Food of Plants : GRUNDY.
Descriptive and Physiological Botany : HENSLOW.
Botany : SIR J. D. HOOKER.
Agricultural Botany : PERCIVAL.
Handbook of Physiology : HALLIBURTON, 1915.
Manual of Physiology : G. N. STEWART.
Essentials of Human Physiology : NOEL PATON.
Essentials of Histology : SCHAFER.
Text-book of Human Physiology : LANDOIS AND STIRLING.
Physiology : THORNTON.
Animal Physiology : CLELAND.
The Central Nervous System : BINGER-HALL.
Physiology of Muscles and Nerves : ROSENTHAL.
Animal Physiology : CARPENTER.
Manual of Human Physiology : HILL.
The Human Species : HOPF.
The Evolution of Man : HAECKEL.
Text-book of General Pathology : THOMA.
Origin of Species : DARWIN.
The Evolution of Forces : LE BON.
Method and Results : HUXLEY.
Text-book of Electro-Chemistry : ARRHENIUS.
BIBLIOGRAPHY 281
"
The Wonders of Life : HAECKEL.
Effects of High Explosives upon the Central Nervous System : MOTT.
The Evolution of Sex : GEDDES AND THOMSON.
Evolution : GEDDES AND THOMSON.
The Coming of Evolution : JUDD.
The Evolution of Life : BASTIAN.
Transformations of the Animal World : DEPRET.
Consolation in Travel : SIR HUMPHRY DAVY.
The Signs of Life : WALLER.
Evolution of Living Purposive Matter. 1910. MACNAMARA.
Medical and Surgical Use of Electricity : BEARD AND ROCKWELL
Telegraphy : PREECE AND SIVEWRIGHT.
Submarine Cable Testing : BAINES.
Th", Ether of Space : SIR OLIVER LODGE.
Electricity and Magnetism : GORDON.
Telegraphy : HERBERT.
Various Forces in Nature : FARADAY.
Electricity : CUMMING.
Electricity : FERGUSON.
Modern Electrical Theory : CAMPBELL.
Organic Chemistry : REMSEN.
The Science of Light : PHILLIPS.
Journal of Researches : DARWIN.
Meteorology : BUCHAN.
The Story of the Heavens : SIR R. BALL.
Thunder and Lightning : FLAMMARION.
Earthquakes : DUTTON.
Physical Description of the Earth : HUMBOLDT.
Volcanoes and Earthquakes : HOUSTON.
Climate, considered in Relation to Man : WARD.
INDEX
283
INDEX
ABSOLUTE insulation in vegetable
life, 10 et seq., 20, 133
Achromatic fibres, 104
spindle, 103, 111
Acorn, the, 32
Adams, 218
Aerobic micro-organisms, 113
Agriculture and high-tension elec-
tricity, 42
Air as normal " earth," 55, 146, 206
, sign of, 7
Albumins of plants, 158
man, 158
Aldini, 51
Allium odorum, 118
Amides, 132
Amoeba, the, 107, 140
and stimuli, 139
Amoeboid movement, 114, 138, et
seq.
Ampere, experiments of, 141, 189
Anaerobic micro-organisms, 113
Anderson, xxvi
Animal electricity, 50
magnetism, 116
tissues, resistance of, 79
and vegetable cells, 5
Anterior cornu, 216
Anthyllis Vulneraria, 45
Apple, the, 10, 19, 36
, absolute insulation of, 10
Arborisations, 98, 168, 171, 172,
207, 210, 215
Areolae, 44
Arrhenius, 73, 142, 250
Artichoke, Jerusalem, 15, 16
Artificial multipolar cell, 206 el seq.
muscular fibre, 150
Ascaris megatocephala, 110
Asclepias, 127
Asexual reproduction, 112
Asthenia, 260
Athcea rosea, pollen cells, 122
Atmospheric electricity, 271, 275
Attraction sphere, 103, 104, 108
Auditory meatus, 228 et seq.
nerve, 227 et seq.
Aurora borealis, 271
Automatic system, 182
Autonomic ganglia, 202
Axis cylinder, 165, 168, 192, 195,
204, 207, 210
Axon, 168, 190, 204, 212
B
BACTERIA, 113
Baines, F. E., xxv
, G. M., 94
Bamboo, node of, 193
Banana, the, 10, 20
Bar magnets, 117
Barcelona nut, 32
Basilar membrane, 231
Bayliss, 85
Beard, 49
Begonia, experiment with, 159
Bell, 218
Bennett, 3
Berzelius, 217
Bipolar cells, 201, 205, 216
Blastoderm, formation of, 122
Body temperature, 252
Bone connection with muscle, 172
et seq.
Bone, temporal, 228
Bose, 158
Bromides, 263
Brucke, 156
CABBAGE, the, 278
Cajal, 168
Cancer, 244, 263
Capacity in vegetable life, 17 et seq.
of human body, 54, 57, 79,
81, 82, 98, 99, 184, 213
Capacity of liquids, 57 et seq.
in telegraphy, 91 et seq.
test, 101 et seq.
Capillary vessels of lung, 126
Carbon disulphide, 217
rod, 231
Cardiac muscle, 99, 182, 188
Cardiograms, 68, 201
284
INDEX
Carrot, the, 13
Cartilage cells, 122
Catarrh of middle ear, 233
Causes contributing to error, 54
Cells, artificial, 206 et seq.
, bipolar, 201
, multipolar, 198
, nerve, 203 et seq.
, neuroglia, 203
, pigment, 221
of Purkinje, 168
, storage, 200
, unipolar, 201
Cell protoplasm, 138
reproduction, 103 et seq., 1 17
Centriole, the, 103, 106
Centrosome, the, 103, 106, 108, 109
Centrospheres, 114
Cerebellum, 168
Changing sign of impulse, 151, 207,
212
Chemical processes within cells, 3
Chlorosis in plants, 43, 158
Cholesterol, 100
Choroid, 221 et seq.
Chromatin, 114
Chromoplasm filaments, 103, 108
Chromosomes, 103, 110
Chunder Bose, 158
Circulation in foetus, 22, 84
Clausius, 142
Climate and disease, 274
Cob nuts, 33 et seq.
Cochlea, the, 229, 231
Colour in seeds, 31 et seq.
Comparative insulations, 55
Condenser, construction of, 91
, how shown, 171
Condensers in parallel and series,
93 et seq.
Conditions of the earth, 267 et seq.
Conducting layer of seeds, 23 et seq.
Conduction affected by heat, 74,
246, 252
Conduction of stimuli in plants, 130,
131
Conductivity, impaired, 258
of air, 55
Cones and rods, 221, 222 et seq.
Connective tissue, 87, 168, 172, 187,
204
Connection of muscles and bones,
172 et seq.
Constancy of vegetable cells, 37
Constrictions of Ranvier, 195
Contraction of muscle, 52, 147 et
seq., 159
Convection, 56
Conveyance of colour, 220
Copper taping of wires, 163, 164
Corpus striatum, 216
Cucumber, 11
Cucurbita pepo, cells from, 125
Curara and motor nerves, 158
Current, sign of, 244
Cytoplasm, 111
Czapec, 142
DARWIN, 5, 270
Daughter nucleus, 104 et seq., 109
Davis, 39, 112, 157
Davy, 141
Dead muscle, 155, 159
Deafness, nervous, 230
Deflections given by vegetables, 9, 59
Deflection of light rays, 220
Dendrons and synapses, 74, 76, 78,
168, 208, 212, 213
Dengue fever, 275
Diaster, in mitosis, 104
Diatomaceae, 112
Dielectric, 146
, effect of heat upon, 251
treatment, 259
Differences of level, 256 et seq.
Differentiated nerves, 130
Diffusion, 89, 109
, effect of upon vegetableg,
9
Dioncea, reaction of to contact, 128,
158
Dioncea, digestive secretions of, 129
Disease in general, 260
Division of cells, 103 et seq., 117
Dobie's line, 145, 151
Drosera, digestive secretions of, 129
Du Bois-Reymond, 51, 152, 156
E
EAR, the, 217, 228 et seq.
, faults in, 232
Earth, conductivity of, 6, 7, 38, 43,
274
Earth, electrical conditions of, 267,
et seq.
Earth connection, 242
currents, 270 et seq.
, sign of, 7
Earthquakes, 272
Edible chestnut, 27 et seq.
parts of vegetables, 6
Effect of electrical stimulation of
plants, 39, 40
Elastic tissue, 87
Elastin, 207
Electrical aspect of seeds, 22 et seq.
INDEX
285
Electrical disturbances in plants, 4
et seq.
Electrical conditions of the earth,
267
Electrical equilibrium, 109
laws, 146
,, particles, 90
stimulation of plants, 39,
40
Electrical stimulation of muscles
and nerves, 178 et seq.
Electrical stimulus of nerves, 75,
107, 178
Electrical tensions between air and
earth, 5
Electrical units, 245
Electricity, atmospheric, 271
in agriculture, 42
in relation to vegetable
poisons, 277
Electricity, molecular theory of, 1 69
Electrodes, theories concerning, 8,
52, 59 et seq., 68
Electrodes and electrolysis, 20, 35,
36, 242, 244
Electrodes, reliability of, 60 et seq.
, thumb pressure on, 69
; , , the, 242-4
Electro-cardiograms, 68, 201
Electro-diagnosis, 234 et seq.
Electro-magnetic waves, 226
Electromotive force of vegetables,
37
Electromotive mechanism in plants,
Electrons, vibrations of, 226
Electro-physiology of the motor
apparatus, 144 et seq.
Elodea, cells from, 134
End-plates, 150, 165, 166, 179,
180, 207, 210
Endolymph, 229
Endoneurium, 76, 162
Endothelium of a serous mem-
brane, 125
Energy, source of body, 85
, storage of, 87
, conveyance of, 89
Engelmann, 228
Enzyme action, 113, 132
Epineurium, 163
Epilepsy, 259, 261
, safety-valve in, 262
Epiphysis, 173
Epithelium cells, 118, 124, 222, 229
Equatorial plane, 115
Equilibrium, 67, 105, 109, 196, 200,
252, 261
Error, factors of, 53
, causes contributing to, 54, 58
Euphorbia, 127
Eustachian tube, 229
Evidences of the law, 118 et seq.
Evolution, theory of, 5
Excessive nervousness, 259
Excised muscle, 58, 155, 159
Excitability, 154, 156 et seq., 179
Exoplasm, 106, 109
Eye, the, 217 et seq.
, artificial, 218
FARADAY, 142, 146, 163
B'ats in animals and plants, 132,
247, 256
Fatty acids, 133
" Faults " in the ears, 232
, various, 259
Fenestra ovalis, 229, 231
rotunda, 229
Ferro-sulphate as an electrolyte, 38
Ferruginous soils, 274
Fertilisation of the ovum, 110, 119
Fever, dengue, 275
, malarial, 275
, yellow, 275
Fibres of Purkinje, 99
Fibrils of nerve-fibre, 121
Fibro-cartilage cells, 123
Fibrous tissue, 87
Fick, 155
Finger-tips, 88
Finlay, xxv, xxvii
Flammarion, 271
Foetus, circulation of, 22, 84
,, , the developing, 88
Fovea centralis, 221
Frey, 126
Fucus, 112
Fuscin, 228
G
GALVANI, 50
Galvanometer connecting wires, 242
, D'Arsonval, 18, 238
, Kelvin, 7, 54, 234 et
seq.
lamp, 241
scale, 239
short-circuit keys, 241
string, 68
, importance of, 259
and psychological in-
fluence, 68
Galvanometric diagnosis, 244, 246,
247
Ganglia, autonomic, 202
Ganglion cells, 120, 196 et seq., 216
286
INDEX
Gas gangrene, 159
Gaskell, 125
Gasserion ganglion, 215
Gastrocnemius of frog, 98
Geddes, 117
Generating station of the body, 82
Generation of nerve-force, 84 el seq.,
183
Glandular organs in plants, 129
Golgi, 166, 203
Gordon, 224
Grape-fruit, 12
Green, 4, 128, 129, 135
Growth, stimulation of, 7, 40
Guard cells, 129
Gutta-percha, relative resistance of,
251
Gymnosperm, ovule of, 124
Gynostemium of Stylidium, rigor
in, 143
H
HACKELE, 210
Haemoglobin, 85
Halliburton, 73, 78, 107, 138, 142,
161, 167, 178, 198, 203, 211, 222,
227, 231
Hand-to-hand deflection, 65, 69,
80, 183, 231, 242, 249
Health in the tropics, 275
Hearing, mechanism of, 230
Heat, effect of upon dielectrics,
251
Heat, effect of upon conductors,
252
Heaviside, 7
Hensen, plane of, 151, 152
Hetero and homotypical mitosis,
110
High frequency treatment, 42, 71
High tension current in agriculture,
42
Holmgren, 205
Hopf, 101
Horse-chestnut, 23 et seq.
Hoy a Carnosa, section of, 121
Humboldt, 50
IMMATURE seeds, 23
Impaired conductivity, 258
Impulses, visual, 222
Impulse, nature of nerve, 73 et seq.,
201
Impulse, rate of propagation of
nerve, 78, 89, 98, 213
Impulse, nerve, how transmitted,
169
Incus, 229
Induction, 146, 160, 270
Inductive capacity, 57, 91 el seq.,
146
Inductive embarrassment, 160
interference, 75, 162 et
tion, 74, 77, 183
Insomnia, 259
Insulating processes of the body,
161
Insulating system of seeds, 23 et
seq.
Insulation of vegetables and fruits,
10 et seq.
Insulation of body structures, 86
Insulations, comparative, 55
Interstitial protoplasm, 213
Intra-cellular action, 77, 113
Involuntary muscle, 178, 184 et
seq., 203
lonisation, 141
Ions, 77, 85, 140, 142, 250
Iris pumila, 118
Iron in body, 189, 203
as an electrolyte, 42
in plants, 43
soil, 38, 44
Irritable organs in plants, 131, 157
Irritability, 105, 130, 132, 143, 157,
180
Irritation of nerves, 75
JACKET of vegetables, 6
Jamieson, xxv
Jerusalem artichoke, 15, 16
K
KABSCH, 143
Karsten, 5
Karyokinesis, 114, 118, 119
Kennelly, xxv
Kephalin, 100
Kinoplasm, 114
Kinoplasmic spindle, 114
Kolliker, 127
Krause's membrane, 100, 145, 152,
155
I,
LABYRINTH, 228
Lamina spiralis, 229
Landois and Stirling, 79, 127, 145,
154, 160, 230
Latex cells, 127-134
Laticiferous vessels, 126, 134
Leaf of horse-chestnut, 16
ivy, 16, 17
INDEX
287
Leaves, deciduous and evergreen,
16
Le Bon, viii, 89, 142, 200
Lecithin, 100
Lemon, the, 12
Txivel, differences of, 256 et seq.
Life of vegetables, 36
Light, electro-magnetic theory of,
226
Light, rays of, 219 et seq.
Light-rays, deflection of, 220
Lightning, 268 et seq.
Lignified fibres of a leaf, 44
Lilium martagon, pollen grain of,
119
Living nerve, resistance of, 79
Lobar pneumonia, 254
Local action in fruits, 36
pyrexia, 232, 244, 251, 253 et
seq.
Longridge, experiments of, 61 et seq.
Lycopodium, cells from, 123
Lymph space, 75, 76, 162
M
MACALLUM, 189, 203
Macdonald, 77
M'Gregor Robertson, 55, 175
Macula lutea, 221
Magnetic lines of force, 117, 164
Magnets, bar, 117
Maimbray, 42
Malapterurus, electrical organ of,
203
Malarial fever, 275
Malleus, 228
Mangel-wurzel, the, 12
Martin, vii, 63 et seq., 82 et seq., 263
Massee, 113
Mastoid, 232
Matteucci, 51
Maxwell, 73, 226, 252
Mechanism of hearing, 230
Medulla oblongata, 215
Medullary sheath, 100, 121, 166
Melanin, 228
Membrane of Krause, 100, 145, 152,
155
Membrane of Reissner, 231
Membranes of seeds, 23 et seq.
Metabolism, 127
Mimosa pudica, motile organs of,
143
Mitosis, 103 et seq. t 110, 115, 118
Mitotic nucleus, 105
Molecular movements in plants, 4
,, theory of electricity, 169
Motile organs of Mimosa pudica,
etc., 135, 137, 143
Motor mechanism in plants, 128
158
Motor nuclei, 214
Mott, 168, 190
Movement of protoplasm in plants,
135
Mucor, 112
Mttller, 130
Muitipolar cells, 198, 205 et seq., 216
cell, artificial, 206 et seq.
Munk, 76
Muscle, cardiac, 182, 184, 185
curve, 160
,, spindles, 210
telegraph, 152
Muscles, connection with bones ,
172 et seq.
Muscles, deltoid, 174
, fan-shaped, 174
, pennate, 174
,, , semi-pennate, 174
Muscular contraction, 147 et seq.,
160
Muscular fibre, artificial, 150
fibre-cell, 123
,, paralysis, 180
,, tissue, 144, 147 et seq.
Mustard seed, experiment with, 38
Myxogaster, 113
N
NATURAL dielectrics, 89, 100
insulation resistance, 172,
201
Negative and positive, 82
Nerve-bundle, section of, 125
Nerve cells, 203 et seq.
centre, definition of, 202
conduction, rate of, 74, 213
deafness, 230
degeneration, 179, 193
energy, 55 et seq., 183
energy of toads and tortoises,
156
Nerve fibres of voluntary muscle,
150
Nerve force, 5, 6, 55, 189, 252, 256
,, ,, , generation of, 84 et
seq., 183
Nerve impulse, nature of, 6, 73 et
seq., 201
Nerve impulse, how transmitted,
169
Nerve impulse, velocity of, 78, 227
poisoning, 158, 258
regeneration, 194
,, , resistance of living, 79
unit, 210, 211
Nerves, differentiated, 130
288
INDEX
Nerves, irritation of, 75
of plants, 157, 158
, auditory, 227 et seq.
, cranial, 215
, hypogastric, 203
, motor, 147, 156, 165 et
seq., 180
Nerves, non-medullated, 144, 251,
253
Nerves, olfactory, 222
, optic, 130, 220 et seq.
, pelvic, 203
, peripheric, 75, 76
, sciatic, 75
, sensory, 194, 200, 214, 216,
231,256
Nerves, splanchnic, 203
, trigeminal, 216
,, , vagus, 182
,, , vaso-motor, 86
, vaso-inhibitory, 86
Nervous breakdown, 259
energy, 183
Neurasthenia, 260
Neurilemma, 161, 165, 204, 251
Neuritis, 158, 258
Neuro-electricity, 55 et seq., 67, 107
204, 226, 254
Neuroglia, 168, 171, 203
Neuro-keratin, 100
Neurons, 168, 171, 191, 198, 222
Neuro-synapse, 171
Nissl's granules, 168, 189, 207
Nobili, 51
Nodes of Ranvier, 192 et seq., 204
Noel Paton, 147
Noll, 5
Non-polarisable electrodes, 57, 58
Non-living, the, 120, 155
Nuclear disc, 115
membrane, 109, 112, 114
poles, 105, 106
Nucleo-protein, 138
Nucleus and nucleolus, 107, 108 et
seq., 114, 115, 189, 211
Nutrition or conductivity ? 178
Nuts and seeds, secretion of, 26 et
seq.
Nux vomica, effect of upon con-
duction, 140, 159
O
OHM'S law, 179, 198, 231, 245 et
seq.
Ohm's law and solutions, 250
Oil-glands of the orange, 12
Onion, the, 14, 18, 19, 36, 60
Oospheres, 112, 119
Optic axis, 224
Optic nerve, fibres in, 220
Ora serrata, 222
Orange, the, 12, 21
Osmosis, 10, 138
Ovule of gymnosperm, 124
Ovum, 111
, fertilisation of, 119
, segmentation of, 110
Oxygen, intake of, 43, 183
PALMS of the hands, 56, 65
Pancreas, secretion of, 133
Parallelogram of forces, 174, 177
Paralysis, muscular, 180
Parsnip, the, 13
Particles, electrical, 90
Passiflora, sense of touch of, 130
Paton, Noel, 147
Pear, the, 10, 36
Peel of fruits, 6
Pender, xxvi
Perilymph, 229
Perineurium, 75, 162
Peripheric nerves, 75, 76
Persistence of vision, 221
Personal capacity, 57
Peters, 132
Phalaris, sense of light of, 130
Phaseolus multiflorm, 120 122
Phillips, 226
Pigment cells, 221, 227, 228
Piper, experiments of, 98
Plain muscle, 99, 101, 144, 178, 184,
et seq., 203
Plane of Hensen, 151
Plants grown in pots, 7, 9, 40
in dry climates, 133
, how electrified, 8
resting, 37
Platinum, secondary action of, 7
Plexus of Auerbach^ 167
Plexuses of involuntary muscle, 167
Pneumonia, 254
Poisoning, vegetable, 277
Polar bodies, 110
regions, 276
Polarisation, 35, 36, 67, 68
_Polarity, difference of in hands, 61
et seq.
Pons varolii, 171, 215
Positive and negative, 82
Potato, the, 15
Potatoes, experiments with, 40
Power of taste and smell in plants,
128
Preece, xxv, 91
Primary or secondary cells ? 86
Pronuclei, male and female, 110
INDEX
289
Propagation of impulse, 76, 89
of stimulus in plants,
136
Protoplasm, interstitial, 213
, death of, 139
, movement of in plants,
135, 138, 158
Protoplasm, network in, 113, 114
Protozoa, 112
Purkinje's cells, 168
fibres, 99
Pyorrhrea, 258
Pyrexia, local, 232, 244, 253 et seq.
Q
QUANTITY and tension, 198
Quince, the, 10, 17, 36
R
RADCLIFFE, 52
Ranvier, 122
, band of, 195
, nodes of, 192, 19G
Rate of propagation of nerve im-
pulse, 78, 89, 98, 213
Rate of stimulation, 98
Rays of light, 219 et seq.
Reduction-division, 110
Reflex action, 98, 212, 214
Reissner, membrane of, 231
Relative resistance of gutta-percha,
251
Relays, system of in the body, 74
Repair outfit, 16, 31
Reseda odorata, protoplasm of, 124
Resin in plants, 134
Resistance of animal tissues, 79
nerves compared, 79
skin, 69
Response of muscles and nerves to
stimulation, 178 et seq.
Resting nucleus, 104
Retardation, 74, 76, 78, 91
Retina, 221 et seq.
Rhubarb, capacity of, 19
, leaves of, 277
Rhythmic movement in plants, 135
Rice, grain of, 113
plant, 39
Rigor in plants, 143
Rind of fruits, 6
Robertson, M'Gregor, 55, 175
, A. White, vii
Rockwell, 49
Rods and cones, 221
Rosenthal, 75 et seq., 116, 166, 175
Ross, Earl of, 218
SACCULE, 229
Sachs, 4, 43, 118, 121, 126, 130, 137,
143, 158
Salivary gland, section through, 123
Salts in blood plasma, 142
vegetables, 127
Saprophyte, 113
Sarcolemma, 145, 150, 153, 161,
165, 167, 251
Sarcomeres, 52, 97, 147 et seq., 155,
161, 166, 180
Sarcous substance, 145, 188
Savoy cabbage, 43
Scala tympani, 229
vestibule, 229
Schafer, 103, 105, 108, 110, 115,
118, 120, 122, 124, 138, 153, 168,
185, 189, 204, 214, 224
Schenck, 5
Schizomycetes, 112
Schultze, 207, 210, 221, 224
Schwann, white substance of, 193
Sciatica, 158, 258
Sciatic nerve, 75, 98, 122, 162
,, plexus, 75
Sclerenchymatous fibre, 123
Scorzonera hispanica, laticiferous
vessels of, 126, 127
Screened cable, 163
Sebaceous glands, 56, 65, 255, 258
,, secretion, purpose of, 133
Secondary action of platinum, 7
Secretion of nut seeds, 26 et seq.
Seed substance, electrification of, 24
Seeds in their electrical aspect, 22
et seq.
Segmentation of the ovum, 110
Selenium, 219, 223
cell, 217
eye, 218
Sense-organs in plants, 128, 130
Sensory nerves, 194, 200, 203, 212,
214, 216, 231, 256
Sensory nerves of plants, 130, 157
nucleus, 215
nuclei, 216
Sexual reproduction, 112
Sharpey, 147
Sherrington, 85
Siemens, 218
Sight in plants, 128
Sivewright, 91
Skin currents, 88
resistance, 69
Sleeping sickness, 275
Smirnow, 124
Smith, Willoughby, 218
Soil, application of electricity to, 3
U
290
INDEX
Somatic cells, 118
Some evidences of the law, 118 et
seq.
Source of energy, 85
Specific energy of tendrils, 131
inductive capacity, 81, 89,
100
Spermatozoids, 112, 119
Spermatozoon, 110
Sperm cell, 110
and germ nuclei, 110
Spinal cord, section of, 120
ganglion cells, 200
Spindle-fibres, 105, 107
Spirem, 103
Spirogyra, 112
Stapes, 228
Starch cells, 113
Starch-sugars of plants, 158
Static charge in body, 53
Stewart, 192
Stimuli, various forms of, 139 et
seq.
Stimuli and the amoeba, 139
not various forms of
energy, 154
Stimulation of plants, 39, 40, 129,
136
Stimulation, rate of, 98
Stomata, 129
Stone, xxviii
Storage cells, 54, 200, 202
of energy, 87
Strasburger, 118, 124
Striated muscular fibre, 97, 99, 100,
144, 147 et seq., 165, 166, 184
String galvanometer, 68
Structure of the body electrical, 71,
74
Submarine cable, core of, 163
Sugar-glycogen of man, 158
Suggestion, 68
Sulphur, 100
Sweat-glands and deflections, 65
Swede, the, 12
Sylvian ossicle, 229
Sympathetic ganglia, 171, 204
system, 87, 196 et seq.,
204
Synapses, 74, 76, 78
Synapses and dendrons, 168 et seq.,
212, 213
System of relays in the body, 74
Szczepanik, 219, 226
Szymonowicz, 166
TAINTER, 218
Tea and tobacco plants, 278
Telectroscope, 219
Temperature of the body, 252
Temporal bone, 228
Tendrils, specific energy of, 131
Tension and quantity, 198
Tensor tympani, 229
Termination of nerves in muscle,
165
Testing, note for guidance in, 44
the body, 89
Thomson, 117
Thornton, 202, 222, 230
Thumb-pressure on electrodes, 69
Thumbs and fingers, signs of, 63 et
seq.
Thunderstorms, 267 et seq.
Toad, nerve energy of, 156
Tobacco and tea, '278
Tomato, the, 11
plants, experiment with, 40
Tortoise, nerve energy of, 156
Tradescantia, section of, 125
, staminal hairs of, 185
Transpiration in plants, 133
Trench foot, 63
Trichomes, 112
Tropics, health in the, 275
Trowbridge, 52
Tubers, 14
Turgidity in plant organs, 135
Turner, 203
Turnip, the, 12, 13, 20
Tympanum, 228
U
ULTRA-VIOLET rays and plants, 130
Unipolar cells, 121, 194, 201, 203,
205, 210, 214, 216
Units, electrical, 245
Urates in the ear, 232
Usnea barbata, section of, 121
Utricle, 229
VAGUS nerves, 182, 259
Van't Hoff, 73
Various " faults," 259
forms of stimuli, 139 et seq.
Vascular connective tissues, 87
system, 126
Vaso-motor and vaso-inhibitory
nerve-fibres, 86
Vaucheria Sessilis, spore of, 120
Vegetable cells, constancy of, 87
poisoning, 277
protoplasm, 129
Velocity of ions, 250
nerve conduction and
heat, 252
INDEX
291
Velocity of nerve impulse, 78, 89,
98, 213
Venation of leaf, 44
Vestibule, the, 229
Vines, 4, 114, 132
Viola tricolor, glandular colleter
from, 123
Vision, persistence of, 221
Visual impulses, 222 et scq.
purple, 223, 228
Volcanoes, 273
Volta, 50
Voltaic pile, 51
Voluntary muscle, 97, 99, 100, 144
147 et seq., 165, 166, 184, 216
Voluntary muscle, nerve fibres of,
150
Voluntary system, 86, 97, 216
W
WALLACE, 5
Ward, 275
Water in its relation to plant life, 38
Wax in plants, 13
Wheat, grain of, 113
Womb, section of pregnant, 124
Wundt, 155
YELLOW fever, 275
Z
Zea mays. 121
Zygospore, 112
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