The New Student's Reference Work/Ammonia

Ammo'nia, a (NH$3$), which is dissolved by water with great avidity, making an  liquid called ammonia-water or, by chemists, ammonium hydroxide, which is the common form in which it is used. The name is probably derived from the temple of in the Libyan desert, where ammonia was produced. The name hartshorn is also used, because the shavings of have been used to prepare it. It is composed of and, and is obtained chiefly from the waste liquors of the manufactories of illuminating gas. Ammonia gas may be changed to a liquid or solid by cold and pressure. An important use of liquid ammonia is in the manufacture of ice. (See .) Ammonia unites with to form ammonium. The is much used for smelling salts, the  is used in soldering and in medicine, and the  and other salts are valuable.