Ship's after six-inch gun and its crew, April 1917. The two officers at right are identified, in the original photo caption, as Lieutenant Ware and Captain Emory Rice of the U.S. Naval Reserve Force. Note shells on deck, painted with letters: T-E-X-A-S and T-E-D-D-Y Mongolia was assigned a Navy armed guard on 17 March 1917. She engaged a German submarine on 19 April 1917, the first U.S. ship encounter with a U-Boat after the United States entered World War I. U.S. Naval History and Heritage Command Photograph.