Page:Guide through Carlsbad and its environs.djvu/15

 carbonate of soda, $10 1/2$ grs.; muriate of soda (common salt), nearly 8 grs.; carbonate of lime, above 2 grs.; sulphate of potash, above 1 gr.; carbonate of magnesia, 1 gr.; siliceous earth, about $3/4$ gr.; and oxidulate of iron, hardly $1/20$ gr. The proportions of all these constituents, with the exception of the siliceous earth, were stated with approximate accuracy by Dr. Becher, in 1766. Later analysis has revealed some other constituents, but only in very small quantities, namely: carbonate of iron, oxidulate of manganese, phosphate of alumina, phosphate of lime, fluoride of potassium, iodide and bromide of sodium, lithium, boracic acid, rubidium, czesium, and arsenic.

The Schlossbrunn contains (according to Wolf) somewhat over 17 cubic inches of carbonic acid gas, the Mühlbrunn 13, and the Sprudel 8, in one pound of water.

The Sprudel has the property of covering, in a short time (about three days), objects, such as wood, earthenware, the solid parts of plants, such as grains, acorns, thistles, &c., with a strong crust of a yellow or yellowish brown colour, which consists principally of lime and siliceous earth; the yellow colour is due to iron.

Concerning the origin of the Sprudel, modern Geology explains it, as follows:—The atmospheric water, by percolating to the depth