On the RECRUIT - Glass negative photogrpah. Public domain.

Photograph shows a sailor demonstrating a "machine gun" aboard the U.S.S. Recruit, a fake battleship built in Union Square, New York City by the Navy to recruit seamen and sell Liberty Bonds during World War I. The photograph was taken on Memorial Day, May 30, 1917, the day of the "launch" of the ship. (Source: Flickr Commons project, 2014)