PROOFS OF THE PROPERTIES OF SILVER.

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Experiment VII. (

Muriatic acid docs not attack silver, lut separates it fromits solution.

I-ct fall some muriatic acid into a solution of nitrate of silver,a white curdy precipitate will be instantly formed in great abun-dance. This precipitate is decomposed by light, for if it be ex-posed to the direct rays of the sun, the white colour will bechanged to brown and afterwards to black. If fused by a gentleheat it forms a semi-transparent mass of the consistency of horn ;hence it was formerly called horn-silver , but now' more properlymuriate of silver.

Remark. ..To reduce muriate of silver, let one part of it bemixt with three of soda, and exposed to a white heat. Whenthe mixture is well fused, suffer it to cool; then break the cru-cible, and separate the silver from the muriate of soda which hasbeen formed. The silver obtained by this means is exceedinglypure.

Experiment VIII.

Preparation of ammoniated oxid of silver.

(Bcrlhollefsfulminating silver.J

Dissolve fine silver in pale nitric acid and precipitate the solu-tion by lime water; decant the fluid; mix the precipitatewith liquid ammonia and stir it till it assumes a black colour;then decant the super-natant fluid and leave it in the open air todry. This product is fulminating silver, invented by Berthollef,which when once obtained cannot he touched without producinga violent explosion. It is the most dangerous preparation known ;for the contact of fire is not necessary to cause it to detonate.It explodes by the mere touch of any substance. Its very pre-

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