that is the head stamp for the Hotchkiss company, Pairs. France one of the earliest producers of "modern" cases ad projectiles from around the late 1870s. They sold to countries all over the world, so it is difficult to put a country of use label on one of them. They also made the guns which fired them, the most familiar being the 5 barrel evolving gun in various calibers up to 47mm. examples Found in37mm and up to 3" or larger.#
', and possibly larger. Used as anti torpedo defense on ships and flank defense in fortifications .Many a collection has started out with the37mm example.