Amerik. Fliegerbombe Blindgänger

American day bombardment started in June 1918. On the 12th of June the 96th Aero Squadron bombed the railroad yards at Dommary-Baroncourt. This photo showing to German soldiers and an unexploded American is updated and could be from any raid.

Coney Island Air Corps

Another card from the same studio dated 1918 can be found here.