An article I was reading refers to an armored train carrying a "German revolver (caliber 3.7 mm)" (they mean 3.7cm/37mm), among other weapons. Perhaps it was a Hotchkiss 1-pounder, 37 mm, with 5 barrels, made by Krupp under license. Can anyone tell me more about the weapon? Are there other possible 37 mm "German Revolvers" or is this the only likely candidate? Or don't I have the correct description?
You are quite right in suspecting the system in question was of Hotchkiss origin. These guns were used prolifically by the Germans; particularly Ballon sections who had a batterie (2 guns) organic to their unit.