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of great importance in sundry cases, particularly for pro-curing fresh water easily at sea, I was engaged by the lateDr. Hales, whose extensive philanthropy will ever renderhim dear to mankind, and who had this salutary objectgreatly at heart, to undertak" a set of experiments directlywith this view ; the result of which shall be communi-cated in a separate article of some of our future 'publica-tions.

A YVind-furnace, for the fusion of metals, theassaying of ores, and other like uses, is formed by invert-ing one pot over the other; and placing on the top eitherthe entire chimney, or two or one of its pipes, accordingas the fire is wanted to be more or less strong. The secondgrate, in the middle of the undermost pot, is generally,in these intentions, more proper than the lower small onemade use of in the former cases, on account of its havingmore interstices for admitting air to the fuel. The crucible,containing the subject-matters, is placed upon a circularslip of brick, or of a broken pot, a little wider than itsbottom, laid upon the middle of the grate, to prevent thecold air from striking on it. The charcoal is put inthrough the fire-place door, or larger aperture, of thedome or upper pot, which should always be closed aftereach supply of fuel. The furnace stands on its trevet oropen foot; with the flat iron pan underneath, not onlyfor receiving the ashes, but that, if the crucible shouldhappen to fail during the fusion, its fluid contents may bepreserved. The two opposite holes in the upper part ofthe dome afford the conveniency of pasting an iron rodthrough, for safely and commodioully listing it whenintensely heated.

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