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PROOFS OF THE PROPERTIES OF SILVER.

Experiment V.

Silver decomposes concentrated sulphuric acid, at a boiling heat.

Put one part of silver tilings into a retort, pour over it sixof concentrated sulphuric acid and heat the mixture over a lamp;the acid will be decomposed and sulphureous acid gas will beobtained. The residue in the retort is sulphate of silver, whichby solution in a large quantity of boiling water, and evaporation,may be obtained ir) the form of small needle-shaped crystals.

Experiment VI.

Silver is dissolved ly nitric acid, ivith great rapidity.

Pour nitric acid of a moderate strength, upon some silver ina Florence flask ; an effervescence will take place, the metal willbe dissolved and nitrous gas will be liberated copiously. If boththe silver and acid were perfectly pure, the solution will be co-lourless, but if otherwise, it will have a milky or greenish hue.If the solution be evaporated it shoots into tabular or scaly cry-stals, called nitrate of silver.

Remark.. .A solution of nitrate of silver, stains animal andvegetable substances a deep black; and the colour produced isexceedingly permanent, hence it has been applied for the stainingof human hair; but when thus made use of, it should be very-much diluted, and used with great caution, on account of itscorrosive property.

The article known by the name of indelille, or permanent,marking ink for marking linen, wearing apparel, &c. consists ofa solution of nitrate of silver, thickened with a little gum arabic.

The fluid known by the name of silver-test, for detectingcounterfeit silver coin is a solution of standard silver considerablydiluted.