Appendix.

999

2. Silica, (Geyzer, My/cum, Carlsbad, Pongues, Pit.) '

3. Lime, [doubtful.)

IV. Compound Salts : ,

1. Sulphate of Soda, (very common.')

Ammonia, {some volcanic springs. )

2.

S.

4.

5.

6.

7.

8.

9.10.11.12.13.14.15.16.17.18.19.20.21.22.23.24.25,

— Lime, [very common.) *

— Magnesia, (Epsom and many other springs.) 3

— Alumina, (very rare.)

— Iron, (volcanic springs.)

— Copper, (waters from copper mines.)titrate of Potash, (some springs in Hungary, rare.)

■ --------------Lime, (some springs in Arabia.) 4

---------------Magnesia, (rare.)

Muriate of Potash, (Uhleaborg, Stveden, rare.) 5

-------------•- Soda, (very common.)

---------------Ammonia, (some firings in Italy and Siberia.)

---------------Barytes, (very uncommon.)

---------------Lime, (very common.)

---------------Magnesia, (very common.)

---------------Alumina, (uncommon.) 6

---------------Manganese, (Lymington Priors.)1

---------------Carbonate of Potash, (rare.)

--------------- Soda, (very common.)

Ammonia, (rare.)

---------------Iron, (common.)

Hydrosulphuret of Lime. ~---------------------------- 1 Soda,

>(no(

uncommon in sulphureous springs. )

Sub-borate of Soda, (lakes in Persia and Thibet.)These substances are not all contained in any mineral water, seldom more thanfive or six being present together; and they are generally in very minute quantity,the character and properties of the water depending on one or two ingredienttwhich predominate. This allows mineral waters to be arranged into the four fol-lowing classes : 1. Acidulous waters ; 2. Chalybeate waters ; 3. Sulphure-ous waters ; 4. Saiiss waters. We shall first give a sketch of the physicalcharacters and medicinal properties of each of tV^ese classes ; and then describe themethod of determining the ingredients, and their proportions, contained in anymineral water.

1. Acidulous waters owe their properties chiefly to carbonic acid. Theysparkle when drawn from the spring, or when poured into a glass ; have an acid-ulous taste, and become vapid when exposed to the air. Besides free carbonicacid, on the presence of which these qualities depend, acidulous waters containgenerally also carbonates of soda, of lime, of magnesia, and of iron ; and some-times muriate of soda. They may be divided into thermal or warm acidulouswaters, and cold acidulous waters; the temperature ol the former, however, doesnot exceed 72°, while that of the latter is generally about 55°.

The most celebrated springs of this class are Pyrmont, Seltzer, Spa, and Carls-bad. They are tonic and diuretic; and in large does produce a sensible degreeof exhilaration. They all afford a grateful and moderate stimulus to the stomach ;but the Pyrmont, Spa, and Carlsbad, containing carbonate of iron, are especiallyuseful in all cases of impaired digestion ; while those which contain alkaline car-bonates, as the Carlsbad and Seltzer, are more particularly employed as palliativesin calculous affectiens.

2. Chalybeate waters owe their properties to iron in combination generallywith carbonic acid; and as this is usually in excess, they are often acidulous as.well as chalybeate. The metal is found also in the form of a sulphate, but theinstances of this are very rare.

Chalybeate waters have a styptic or inky taste; they are, when newly drawn,transparent, and strike a black with tincture of nut-galls ; but an ochrey sediment

• Dr, Bergman. <* D r . LUter, in 1682. 3 Dr. Grew, m 1610. ■» Dr, Home,

in 1756. 5 Julin, 6 Dr. Withering. 7 Bergman,

3M2