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PROPERTIES OF FLUATES.

ing one part of water, and apply a gentle heat. The fluoric acidgas disengaged will be absorbed by the water and form liquidfluoric acid, which must be kept in well closed leaden or tin bot-tles, or phials coated within with wax or varnish.

Fluoric acid united to different bases forms saline compoundscalled FLUATES.

. PROPERTIES OF FLUATES.

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Fluates may be decomposed by the affusion of dense sulphuricacid; but not by heat, or by combustible bodies. When stronglyheated they become phosphorescent, emitting in the dark a lam-bent white light.

Remark. ..The fluates of lime possess particularly this lastproperty, those fluates which exhibit the most lively and varie-gated colours, constantly shine with a light inclining to theviolet, with the single exception of the Siberian variety, whichhas been named chlorophane ; and which, though of a violetcolour, gives a phosphorescence of a beautiful emerald green.It emits this light even under water, under oil, or in vacuo.When heated too strongly it ceases to shine altogether.

METHODS OF OBTAINING FLUATES.

Fluate of potash, soda, ammonia, or magnesia, may be prepareed by saturating their carbonates with fluoric acid.

Fluate of barytes is precipitated by adding fluoric acid to thenitrate, or muriate of barytes. Fluate of strontia is prepared ina similar manner.

Fluate of silex is produced by suffering fluoric acid to be incontact with silex. Fluate of iron is obtained by dissolving thered oxid of iron in fluoric acid. Fluate of mercury, fluate oftin, and fluate of silver are precipitated, by dropping fluate ofpotash into the nitric or muriatic solutions of these metals.