USS DeKalb, officer firing a 1-pounder (37mm) Hotchkiss gun while a Sailor observes, 18 May 1918.
U.S. Naval History and Heritage Command Photograph. Catalog #: NH 41702
Fast forward 102 years:
PHILIPPINE SEA (March 10, 2020) Gunner’s Mate 2nd Class Shelby Wilkes fires a Mark 38 25mm machine gun during a live-fire exercise aboard the Arleigh Burke-class guided-missile destroyer USS Mustin (DDG 89).
(U.S. Navy photo 200310-N-AJ005-1173 by Mass Communication Specialist 3rd Class Cody Beam/Released)