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REDUCTIONS BY

A quantity of precipitate per se was put into a chi-na cup placed on hot sand, and some muriatic acidwas poured on it •, the oxid was gradually dissolved,and the digestion continued till the acid was nearlyevaporated, some distilled water was then poured onthe salt, and minute films of a bright metallic ap-pearance floated on the surface.

A nitrate of mercury was evaporated to dryness}the salt acquired a slight tinge of yellow ■, the cupwas removed from the hot sand, and some waterpoured on the salt •, immediately bright films of re-duced mercury appeared, and in about three or fourhours the whole surface of the solution was coveredwith a metallic pellicle, parts of which had the co-lour and splendour of the metal, and other parts re-flected a wonderful yariety of the most beautiful colours.

EXPERIMENT y.

ARSENIC.

A quantity of white oxid of arsenic and muri-atic acid was digested in the same manner in a chi-na cup, a smart heat was continued till most ofthe acid evaporated and left behind a mass of theconsistence of tar, the surface of which had a gray