Of the Tides in the South Seas. By Captain James Cook, F. R. S.

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XXVI. Of the Tides in the South. Seas. By Captain
Janies Cook, F. R, S*

TO SIR JOHN PRINGLE, BART. F. R. S.

SIR,

April 2, 1776.
Mile-End,

R - ^' 6 l8> T N compliance with your requeft, I fend you
my obfervations on the tides in Endeavour
River, on the Eaft Coaft of New Holland, in latitude
15 0 26' S.

About 11 o’clock in the evening of the 10th of June
1770, as we were handing off fhore, the fliip fuddenly
ftruck, and ftuck faff on a reef of coral rocks, about fix
leagues from the land. At this time I judged it was
about high water, and that the tides were taking off, or
deereafing, as it was three days paff the full Moon; two
circumftances by no means in our favour. As our efforts
to heave her off, before the tide fell, proved ineffectual,
we began to lighten her, by throwing over-board our
guns, ballaft, See. in hopes of floating her the next high-
water; but, to our great furprize, the tide did not rife
high enough to accomplifh this by near two feet. We
had now no hopes but'from'the tide at midnight; and thefe
only founded on a notion, very general indeed among

teamen,

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448 Captain Cook’s Account of

feamen, but not confirmed by any thing which had yet
fallen under my obfervation, that the night-tide rifes
higher than the day-tide. We prepared, however,
for the event, which exceeded our moft fanguine ex¬
pectations; for, about 20 minutes after 10 o’clock
in the evening, which was a full hour before high-
water, the Ihip floated. At this time the heads of rocks,
which on the preceding tide were, at leaft, a foot above
water, were wholly covered. I was fully fatisfied with
the truth of the remark, after getting into the river,
where we remained from the 17th of June till the
4th of Auguft, repairing the damage the fhip had re¬
ceived. As this was to be done with the afliftance of the
tides, it led me to make the following obfervations, which
upon any other lefs important occafion might have
efcaped my notice.

The times of high-water on the full and change days
I found to be about a quarter after nine; the evening-
tide, at the height of the fpring, to rife nine feet perpen¬
dicular, the morning-tide fcarce feven; and the low-
water preceding the higheft or evening-tide, to fall or
recede confiderably lower than the one preceding the
morning-tide. This difference in the rife and fall of the
tide was uniformly the fame on each of the three fprings
which happened while we lay in the place, and was ap¬
parent for about fix or feven days; that is, for about
three days before and after the full or change of the
Moon. During the neep, the tide was very inconfi-
derable, and if there was any difference between the rife

of

the 'tides in the South Seas. 449

of the tide in the day and in the night, it was not ob-
ferved.j but to the beft of my recollection none was per¬
ceptible. Excepting two or three mornings, when we
had a land-breeze for a few hours, we had the winds from
no other direction than S.E., which is the fame as this
part of the coaft, and from which quarter I judged the
flood-tide came. The wind, for the moft part, blew a
brifk gale, and rather ftronger during the day than the
night. How far this laft circumftance might affeCt the
evening-tide, I fhall not pretend to determine; nor can I
aflign any other caufe for this difference in the rife and
fall of the tide, and therefore muff leave it to thofe who
are better verfed in this fubjeCt than,

sir, your,8cc.

XXVII. An