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country, I should not perhaps be held excused is I did nottake some notice of it. Copper is to be melted in acrucible, an equal weight of powdered sulphur sprinkledon it, the fusion continued till the sulphur is all burnt off,and the metal afterwards flatted into plates. A quantityof orpiment, auripigmentum, is to be melted and quenchedin vinegar, and the fusion and extinction repeated twenty-four times. The materials being thus prepared, somebean meal is to be placed in the bottom of a crucible,above this nitre and tartar, then some auripigmentum, onthis some of the copper plates with more auripigmentumover them : in this order of stratification we are to proceedtill the vessel is full, and then to invert into the mouthanother crucible having a hole in its bottom. A moderateheat is to be continued so long as any flame or fumesappear, after which the fire is to be raised so as to bringthe matter into fusion, and continued in this state for anhour. It is not to be expected that this process can affordthe ductile gold coloured metal which the author promisesfrom it; for orpiment, in virtue of the arsenic of whichit largely partakes, tinges copper, not yellow, but white..As Vigani throws a veil over some of his preparations,though commonly but a thin one, I have been led to sus-pect that he has done so here; and that by auripigmentumhe does not mean the orpiment which makes a gold pig-ment for the painter, but zinc the auripigment for cop-per. If this explication be right, a yellow metal maydoubtless be obtained, though the troublesome methodof procedure is not to be recommended. The burning ofsulphur upon the copper, and the repeated extinction ofzinc in vinegar, do not appear to be of any advantage - y-and the gradual augmentation of the fire occasions always,as already observed, a great dissipation of the zinc.

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