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PROPERTIES OP BORATES.

evaporate it slowly to one-third, and set it aside to coal ■, whitescales will be deposited, which are boracic acid. After all theacid has been crystallized out of the solution, the salt must bere-dissolved, re-crystallized, and lastly, washed in distilled water,drained on filtering paper and then dried.

2. Boracic acid may likewise be obtained by sublimation, fromtwo parts of sur-saturated borate of soda, one of sulphuric acid,and one of water.

The union of boracic acid with different bases, forms saltscalled borates.

PROPERTIES OF BORATES.

Borates are verifiable by heat, but they are not altered bycombustible bodies. When concentrated solutions of them areboiled with sulphuric, nitric, or muriatic acid, they are decom-posed, and deposit on cooling brilliant lamellated crystals of bo-racic add.

METHODS OF OBTAINING BORATES.

Borate of soda, potash, or ammonia, may be formed by neutra-lizing these alcalies, with a concentrated solution of boracic acid.

Borate of lime is produced, by adding a strong solution ofboracic acid to lime-water. Borate of magnesia is obtained bydissolving magnesia in boracic acid. Borate of alumine is form-ed by mingling a solution of borate of soda, and sulphate of alu-mine. Borate of silver may be formed, by pouring a solution ofcommon borax into a solution of nitrate of silver. Borate ofmercury is obtained in a like manner. Borate of copper is pre-cipitated by mixing a solution of borax with sulphate of copper.

Borate of iron, borate of lead, borate of zinc, and borate ofnickel, may be formed, by adding a solution of borax of com-merce to solutions of these metals in nitric or muriatic acidThe new compounds precipitate.