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conducting the process, according to the quantity of theMatter, the nature of the earthy body, and the conveni-ency of the place; many of which are minutely describedby Agricola in his treatise de re metallica : it will be suffi-cient here to give a general idea of the manner of procedure,in an operation merely mechanical, and whose success de-pends chiefly on manual dexterity acquired by practice.

Where the quantity of matter is small, it is laid by alittle at a time in a round shallow dish called a huddle, orin an oblong vessel like a boat, which being gently shakenbackward and forward, in a tub of water, the lighterpart of the earth is taken up and washed off, leavingwith the gold such sand or small stones as the mixt con-tained. By dextrousty repeating the agitation, that thewhole may acquire as it were a kind of fluidity, the me-talline particles sink to the bottom, and the sand orstones are thrown up to the top, and may be removed bythe hand.

At several of the gold mines of the Spanish West In-dies, the gold is completely separated by this simple ope-ration. According to D’ Uiloa’s account, in his voyageto those parts, the earth, as it comes from the mine, isthrown into a reservoir, a stream of water conducted on it,the whole stirred together, and the muddy water let offinto another and another reservoir : what the water leavesin the first reservoir, and what it deposits in the others,is taken up in trays, or buckets with two handles, andagitated in fresh waters, with an uniform circular motion,till the gold is collected at the bottom.

M. de Reaumur, in the French memoirs for the year1718, gives a particular description of the method ofwashing the gold sands of the Rhine and some otherrivers. A board, five feet long, a foot and a half wide,with a ledge at each side, and at one end, is laid aslope,

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