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of some Calamines. 3 effervescence, and yielded clear colourless glasses; but which became opaque on cooling, if over saturated. Carbonate of soda had not any action on it. • o . c. 68.0 grs. of this calamine dissolved in dilute vitriolic acid with a brisk effervescence, and emitted 9.2 grs. of carbonic acid. The solution was white and turbid* and on standing deposited a white powder, which, collected on a small filter of gauze paper, and well edulcorated and let dry, weighed only 0.86' gr. This sediment, tried at the blowpipe, melted first into an opaque white matter, and then partially reduced into lead. It was there fore, probably, a mixture of vitriol of lead and vitriol of lime. The filtered solution, gently exhaled to dryness, and kept over a spirit-lamp till the water of crystallization of the salt and all superfluous vitriolic acid were driven off, afforded 96.7 grs. of perfectly dry, or aridf t white salt. On re-solution in water, "*' f ; and crystallization, this saline matter proved to be wholly vitriol of zinc, excepting an inappretiable quantity of vitriol of lime in capillary crystals, due, without doubt, to a slight and accidental admixture of some portion of the calcareous fragments on which this calamine had been deposited. Pure martial prussiate of tartar, threw down a white precipitate from the solution of this salt. In another experiment, 20.0 grs. of this calamine afforded 28.7 grs. of arid vitriol of zinc. d. 10 grs. of this calamine were dissolved in pure marine acid, with heat. On cooling, small capillary crystals of muriate of lead formed in the solution. This solution was precipitated 1 ! * Dry, as opposed to wet or damp, which are only degrees of each other, merely jnplies free from mechanically admixed water. Arid, may be appropriated to'express the state of being devoid of combined water B 2