488 Pharmaceutical Preparations. Part III.

powder, grind'it firft with thefulphur, and afterwards withthe fal ammoniac, in fmall quan-tities at a time : then diftil themixture in a retort, with a firegradually increafed. The diftii-led liquor is to be kept, in a bot-tle clofe ftopt, for ufe.

T his liquor has a ftrong offen-five fmell, fomewhat fimilar to thatwhich arifes in the precipitation oflac fulphuris. The vapour in bothcafes fpreads to a considerable di-stance, changes filver or copperutenfils to a brown or blackifhcolour, and produces difagreeablealterations in many medicinal pre-parations : to this circumftancetherefore due regard ought to behad in the performance of that pro-cifs, and in the keeping of thistin&urc. If a piece of paper, writ-

ten upon with a faturated folutionof lead in vegetable acids, andgently dried, be placed in the mid-dle of a quire of paper, or of apretty thick book, and broughtuear the unllopt orifice of the boutie containing thii tinfture, thevapour will quickly reach it, andchange the colcurlefs writing to alegible black.

Hoffman has a great opinion ofthe virtues of this preparation. Hefays, a mixture of one part of thetinfture with three of fpirit ofwine, in a dofe of thirty or fortydrops, proves a moll powerful dia-phoretic ; and that a liquor com-pofed of this and camphor, takesoff the pain of the gout, by bath-ing the feet with it. This tincturemay be a powerful medicine, butit is certainly a very unp'.eafanvone.

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C H A P.