S-1 and S-18 through S-29
S-1 (SS-105)
L-1 riding at anchor while on sea trials, March or April 1916, probably off Provincetown, Mass. A low-lying shore line with houses can be seen in the background, reminiscent of Cape Cod. The L-class were the first US submarines designed to carry a deck gun of any sort, in this case a 3"/23 caliber Mk 9 gun. But it wasn't until the L-9 that guns were installed during construction. The L-1 through L-8 were retrofitted later with the gun. As you can see the L-1 has no gun in this early photo.
S-18 (SS-123)
L-2 in an unknown location, approximately fall of 1916. In July of 1918 while patrolling in the Irish Sea, a large explosion rocked the L-2 about 25 feet on her beam. A torpedo aimed at her by a German U-boat had seemingly detonated prematurely. A periscope was sighted so the L-2 immediately submerged and made an unsuccessful attempt to ram the submarine. with her primitive sonar she couldn't track the U-boat well under water, plus the U-boat had superior under water speed. Later it was suspected that a U-boat had indeed attempted to fire upon the L-2, but another U-boat, the U-65, was unknowingly in the way and was hit by the torpedo meant for L-2. Some time later when the L-2 was dry docked her hull plating was noted to be heavily dented from the close by explosion. The U-65 never returned to her port.