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copper pipe applied to the nose of a pair of double hand-bellows, the antimonial matter gradually exhales in copiouswhite fumes, which cease on discontinuing the blast, andreappear upon renewing it. The fire must from time totime be increased ; for the mass being cooled by the airimpelled upon it, a hard skin forms on the surface, andin this state the evaporation does not succeed. Whenfreffi fuel is to be supplied, the crucible ffiould be covered,that no pieces of the charcoal may fall in ; and as soon as themetal has come again into sufficient fusion, the blast on itssurface is to be repeated, till no more fumes can be madeto rife from it, and the gold remains of a clear bright greencolour without the least cloudiness.

If the process is continued, as it ought to be, to thispoint, there will be no occasion for remelting the goldwith nitre and borax, as the writers on these subjects ge-nerally direct. Where a little of the antimonial matterleft in the gold, discoverable by its paleness and brittlenels,renders this last operation necessary, the nitre and boraxshould be added by a little at a time, the matter beingextremely apt to swell up and run over the vessel: it isthe more disposed to swell up as the antimonial remainsare the more considerable.

This process has been commonly supposed to afford thehighest purification of gold; and hence antimony hasbeen distinguiffied by the title of balneum solius fills, orthe bath which gold alone can support, and by which itis Waffied from all its impurities. But besides that platinacannot thus be separated from it; if gold containing silverbe highly refined by antimony, it will still, on being dis-solved in aqua regia, discover a little of the silver, whichhad been defended by the gold from the action of theantimony. It may be observed in general, that goldcannot be so effectually purified by substances which ope-rate