This version is a derivative of the Internet Archive OGV video with the sound removed by Sookietex on 2011-04-02. The sound added at a later date was most likely not in the public domain.
This media file is in the public domain because its copyright has expired. This applies to the United States, where Works published prior to 1978 were copyright protected for a maximum of 75 years. See Circular 1 "COPYRIGHT BASICS" PDF from the U.S. Copyright Office. Works published before 1923, in this case 1919 are now in the public domain.
This Media file is also in the public domain in countries that figure copyright from the date of death of the artist (post mortem auctoris) in this case Pat Sullivan (February 2, 1887 Ã¢ February 15, 1933 and that most commonly runs for a period of 50 to 70 years from December 31st of that year.