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PROOFS OF THE PROPERTIES OF SILVER.

acid. Mix the solutions, and add to them five or six ounces ofdistilled water. This must be poured upon seven drachms and12 grains of an amalgam of silver of the consistence of butter,which had beeu previously put into a spherical vessel of whiteglass. The vessel must be kept undisturbed, and in about 24hours a very beautiful silver-tree will be formed.

Rationale. ..The mercury contained in the solution attractsthat of the amalgam; the silver contained in the latter acts alsoon that which is held in solution; and the result of these attrac-tions is a speedier precipitation of the silver - The mercury,which makes part of the amalgam, being more abundant thanwould be necessary for precipitating the silver of the solution,produces also a third effect, which is, that it attracts the silverby the affinity and tendency it has to combine itself with thatmetal.

Remark. ..In order to obtain a beautiful vegetation, it is abso-lutely necessary that all the ingredients be of the utmost purity.A cylindrical or conical glass vessel is best suited for it.

Experiment XI.

Precipitation of silver ly copper.

(Vegetation of silver on glass, slate, &c.J

Spread a few drops of a solution of silver in nitric acid, upona smooth piece of slate, or on a plate of glass, by means of acamel's-hair-pencil or feather; place at the bottom of it, in con-tact with the fluid, a copper or brass wire of about one sixteenthof an inch in diameter, and let the whole remain undisturbed ina horizontal position: in a short period of time it will begin tovegetate. Then with a pencil draw a fluid stroke to any part ofthe glass or slate, in order to represent the body of a tree, and