PROOFS OF THE PROPERTIES OF SILVER.

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of silver) on the solution of the oxigenated muriate of alumine,and evaporate it slowly. The product obtained will be a hyper-oxigenated muriate of silver; a single grain of which, in con-tact with two or three of sulphur, will explode violently by theslightest friction.

Experiment X.

Arbor Diana:.

Most metallic substances are capable of decomposing a nitricsolution of silver. The separation of this metal by mercury, onaccount of the phenomena which it presents has been calledDiana’s tree, or Arbor Dianae.

According to Lemery, dissolve one part of fine silver in weaknitric acid to saturation, and, having diluted this solution withabout twenty parts of distilled water, add two parts of mercury.

Homberg's method is to make an alloy in the cold, of four partsof silver-leaf and two parts of mercury; to dissolve this alloyin a sufficient quantity of nitric acid, and to add to the solutiondistilled water.

If we put into this liquor a small ball of a soft alloy of silver,a precipitation of the silver immediately takes place.

Baume gives the following process, which wall be attendedwith more success:

Mix together six parts of a solution of silver and four of a so-lution of mercury, both made with the nitric acid, and com-pletely saturated; add to them a little distilled water, and putthe mixture into a conical vessel, into which have been previous-ly introduced six parts of an alloy made of seven parts of mer-cury and ope of silver.

At the end of some hours there will be formed, at the surfaceof the small mass of alloy, a vegetation in the form of a bush.

A process which succeeds better than any of the former, is todissolve three drachms and 48 grains of pure silver and half asmuch mercury, separately, in a sufficient quantity of pure nitric

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