Colorless, transparent, shining, monoclinic prisms, slightly efflorescent in dry air, odorless, having a mild, cooling, sweetish, afterward somewhat alkaline taste, and an alkaline reaction. Soluble in 16 parts of water at 15° C. (59° F.) and in 0.5 part of boiling water; insoluble in alcohol. At 80° C. (176° F.), it is soluble in 1 part of glycerine. When heated, the powdered salt begins to lose water, then melts, on further heating swells up and forms a white, porous mass, which, at a red heat, fuses to a colorless glass, with complete loss of water of crystallization (47.1 per cent.). Borax in the manufacture of mineral waters is employed to introduce the component boric acid, which sometimes appears in the analysis. Dissolve in its own weight of boiling water for immediate use. If preferred, prepare for stock a solution, by dissolving one part by weight of commercial borax in 99 parts of distilled water (one per cent.). Filter.

Calcium Carbonate (Carbonate of Lime; CaCo3; 100.) - Commercial carbonate of lime in its dry state is but slowly soluble in carbonated waters and takes considerable time to dissolve under pressure, but is soluble in hydrochloric, nitric or acetic acid with copious effervescence. For the purpose of manufacturing mineral waters it is produced by decomposition of chloride of calcium with potassium or sodium carbonate, within the fountain, whereby its solution takes place easily; but where the by-products, viz., chloride of sodium or natrium are no components of the mineral water, calcium carbonate is produced by precipitation for immediate use, being best soluble in its freshly precipitated state, and thus added to the water. To precipitate for immediate use proceed as follows: Dissolve 3 1/2 ounces of carbonate of sodium in 10 to 12 ounces of cold distilled water. Prepare besides a solution of one ounce and one drachm of chloride of calcium. Then mix the two solutions while stirring, and allow one hour for the precipitate to subside. Add this precipitate in its fresh and moistened state to the fountain in the proportions given for the artificial combinations, and agitate while charging the fountain, as it is only soluble by prolonged agitation and under high pressure. It should be prepared for immediate use, but when kept in stock, for a very limited time only, carefully stopper the bottle to protect it from the air and keep it moist.