This description of the Hotchkiss revolving cannon pertains to the Army types, but a brief notice of the naval guns appears in th e Appendix. The breech mechanism of th e 1.85-inch naval gun is illustrated, partly because it is shown on a larger scale than that for the Army piece, and partly because it is a later type, and has some modifications introduced, A plate showing the deck carriage of the largest naval piece - the 2.1 inch - is also included.