MINERAL WATERS, are those waters which contain such a_proportion of for eign matter as to render them unfit for common use, and give them a sensible flavor and a specific action upon the' ani anal economy. They are commonly divi ded into four classes : acidulous or car saline, chalybeate or ferrugin ous, and sulphurcous. In regard to tem perature they are divided into warm and cold. The substances found in mineral waters are numerous : the most frequent being nitrogen, oxygen, sulphur, and car bon, lime, iron, and magnesia. Artificial waters are now made to represent the natural springs, and are equally efficacious as medical agents' so that there are natural and artificial mineral waters. The saline springs are composed of salts of soda and lime, or occasionally magnesia replacing the soda with excess of carbonic acid, and oxide of iron. The chief are those of Pyrmont, Seidlitz, and Epsom. The ferruginous waters have a styptic taste, and are turned black by infusion of nut-galls ; sometimes the iron exists in the water as an oxide dissolved by car bonic acid, sometimes as a sulphate, and sometimes in both conditions together.
Such are the, waters of Vichy, Forges, Passy, Spa, Cheltenham, and Tun bridge : Bedford, Pittsburgh, Yellow Springs in Ohio, Virginia, and Pennsyl vania belong also to this class. Acidu ions waters have an acid taste and extri cate carbonic acid, of which they contain five or six times their volume. They contain carbonates and chlorides of mag nesia and.lime, carbonate and sulphate of iron ; such are the waters of Bath, Bux ton, Bristol, Vichy, Seltzer, New Leba non, &c. They are acidulous. The sul phuretted waters are easily known by their smell and their tarnishing silver and copper : such are those of Harrowgate, Moffat, Aix la Chapelle, Saratoga and Ballston.