1825.] M. Beize/ius on Fluoric Acid. 127 



prisms, and have a two-sided acumination which rests upon the 

 opposite acute angles of the prism. They contain water of 

 crystallization, and become enamel white and opaque when 

 heated. Water decomposes this salt, but to a much less extent 

 than the preceding. The difference between the properties of 

 the salts of barytes and strontian furnishes an easy and exact 

 process, both for distinguishing these two earths from one 

 another, and for separating them when in a state of mixture. 

 For this purpose, a solution of the earths in muriatic or acetic 

 acid is to be mixed with liquid sihcated fluoric acid, and the 

 amount of the barytes is to be determined from the weight of the 

 precipitated double salt. A very small quantity of sulphuric 

 acid precipitates the barytes which remains in solution without 

 acting upon the strontian, and by evaporating the filtered liquid 

 to dryness, and decomposing the residue by sulphuric acid, the 

 latter earth may be obtained in the state ol' sulphate. 



SiUcated Fluate of Magnesia. — A transparent, yellowish, 

 gummy looking mass, easily soluble in water. 



SiUcated Fluate of Alumina. — A clear colourless jelly, which, 

 when dried, splits into fragments, and appears yellowish, but 

 still retains its transparency. It dissolves slowly but completely 

 in water. 



» SiUcated Jiuate of glucina is readily soluble in water, and is 

 converted by evaporation into a colourless syrup, which finally 

 becomes white and opaque. Its taste is astringent, without any 

 admixture of sweetness. 



SiUcated Jiuate of yttiia is insoluble in water, but dissolves in 

 an excess of acid. 



SiUcated Jiuate of zirconia dissolves very easily in water, and 

 may be obtained by evaporation in white crystals, which have 

 tJie lustre of mother-of-pearl. The solution becomes opaque 

 when boiled, but the greater part of the salt continues dissolved. 

 . SiUcated Jiuate of oxide of zinc 1% obtained by dissolving zinc 

 in the liquid acid. It is extremely soluble in water, and is 

 deposited from a concentrated solution in crystals which are 

 generally equiangular three-sided prisms. The crystals are not 

 altered by exposure to the air. 



SiUcated Jiuate oj'oxidule oj'manganese is very soluble in water, 

 and crystallizes on cooling from a concentrated solution in long 

 thin regular six-sided prisms. Sometimes it is obtained by 

 spontaneous evaporation in very short six-sided prisms, which 

 distinctly indicate the rhomboid as their basis. The crystals 

 have a just perceptible tinge of amethyst red. It is converted 

 by ignition into the simple fluate without losing its crystalUne 

 form. 



SiUcated Fluate of Oxidule of Iron. — When a solution of this 

 salt, prepared by dissolving iron filings in the liquid acid, is 

 allowed to evaporate in a capsule of. metallic iron, it shoots in 



