The Collaborative International Dictionary
Ammoniacal engine
Ammoniac \Am*mo"ni*ac\, Ammoniacal \Am`mo*ni"a*cal\, a. Of, pertaining, or containing ammonia, or possessing its properties; as, an ammoniac salt; ammoniacal gas.
Ammoniacal engine, an engine in which the vapor of ammonia is used as the motive force.
Sal ammoniac [L. sal ammoniacus], the salt usually called chloride of ammonium, and formerly muriate of ammonia.