PROOFS OF THE PROPERTIES OF MERCURY.

75

Experiment III.

Preparation of cinnabar, or red sulphuret of mercury.

This is a more intimate combination of sulphur with mercurythan the former, and is prepared in the following manner. Meltin a crucible one part of pounded sulphur, and add to it four ofmercury, stir the mixture in order to assist the union of the sub-stances. When they begin to combine, the mixture takes tirespontaneously; quench the flame by covering die crucible, andhaving suffered die matter to cool, pulverize it in a marblemortar.

Put the powder resulting from it, which is of a violet colour,into a Florence flask, place it on a sand-bath, and proceed tosublimation, by exposing the vessel to a gradually increasingheat till the bottom of the crucible becomes red, and main-tain it in that state for some time, suffer the vessel to cool, andhaving broken it, separate the cinnabar which has sublimed.

Mr. Kirchoff has made us acquainted with another method ofobtaining cinnabar, more simple and elegant dian the former,which is as follows.

Experiment IV.

Let 300 grains of mercury, and 68 of sulphur, with a fewdrops of a solution of potash to moisten them, be triturated in aWedgwood’s, or glass mortar, until it be converted into a blackpowder. Add to diis 160 grains of potash, dissolved in asmuch water. Heat the vessel containing the ingredients overthe flame of a candle, and continue the trituration without inter-ruption during the heating. As the liquid evaporates, add wateifrom time to time, so that the black oxid may be constantlycovered, to the depth of an inch. The trituration must be con-