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together, hy which the gold easily comes off. The otherway is, by putting the gilt silver into common aqua regia,kept so hot as nearly to boil, and turning the metal fre-quently till it becomes all over black : it is then to bewashed with a little water, and rubbed with the scratchbrush, to get off what gold the aqua regia may have left.This last method appears preferable to the other ; as thesame aqua regia may be made to serve repeatedly till itbecomes saturated with the gold, after which the goldmay be recovered pure by precipitation with solution ofvitriol, as directed in the fifth article of this section.

For separating gold from gilt copper, some direct asolution of borax to be applied on the gilt parts, .but nowhere else, with a pencil, and a little powdered sulphurto be sprinkled on the places thus moistened ; the princi-pal use of the solution of borax seems to be to make thesulphur adhere; the piece being then made red hot, andquenched in water, the gold is said to be so far loosened,as to be wiped off with a brush. Others mix the sulphurwith nitre and tartar, and form the mixture with vine-gar into a paste, whicy is spread upon the gilt parts.

Schlutter recommends mechanical means, as being ge-nerally the least expensive, for separating gold from thesurface both of silver and copper. If the gilt vessel isround, the gold is conveniently got off by turning it ina lathe and applying a proper tool, a skin being placedunderneath for receiving the shavings : he fays it is easyto collect into two ounces of shavings all the gold of a giltvessel weighing thrice as many pounds. Where the figureof the piece does not admit of this method, it is to beproperly fixed, and scrapers applied, of different kindsaccording to its size and figure, some large and furnish-ed with two handles, one at each end, others smalland narrow for penetrating into depressed parts. If the

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