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METHOD OF OBTAINING GOLD.

When gold is in a state nearly pure, (native goldj as it is founddispersed among stones, or mixed with sand, it may first bereduced to small granular pieces, together with the matrix ; atable of several feet long, and one and a half broad, with ledgesround three of its sides, and pieces of cloth with a long napnailed on the board, is placed under a gentle stream of water,upon which the pounded ore or sand is thrown; by this contriv-ance, the lighter and heterogeneous substances are washed orcarried oft".

When the stuff or cloth is sufficiently charged with the parti-cles of gold which adhere to it, on account of its superior gravity,it is disengaged from the board, and put into a vessel, where itis further agitated with water, and more freed from the lightersubstances. It is then mixed with ~ of mercury, and trituratedin an iron or copper vessel containing boiling water, until themercury has absorbed all the gold particles. The mercury thuscontaining the gold in solution, is to be separated, first from thewater, next from the earthy particles, and then from the sand,by throwing the whole upon a table placed in an inclineddirection; the mercury charged with gold, but still vivid, willwhen assisted by a little stirring, or manipulation, run off thetable, and leave the sand behind. The mercury is then sepa-rated from the gold, (and silver if any) by exposing the alloyin earthen retorts to such a heat as will occasion the mercuryto distill off, and is collected again in a receiver with water.The gold not being volatile in fire, is thus left behind, and isafterwards further freed from the heterogeneous imperfect me-tallic substances, by the process of cupellation.

After these processes, the silver, if the gold contains any, isseparated by reducing it first to very fine laminae, and then ex-tracting the silver by nitric acid, which leaves the gold behind;the silver may be separated from the nitric acid, by muriaticacid, with which it forms muriate of silver. Muriate of silveris to be decomposed again, by mixing it with soda, and expos-