Page:Theophrastus - History of Stones - Hill (1774).djvu/351

 them; and may erve to explain the Effects of thoe vitriolic Waters which are aid to convert Iron into Copper. A Piece of Iron Wire dipped into any of thee Solutions, and taken almot immediately out again, is een covered with Copper o far as the Mentruum has touched it; and by drawing the Fingers carefully over it, a fine thin Tube of pure Copper may be taken off from it: This may erve to hew us of what Kind the Mentruum is which Nature ues to produce the blue Vitriol from Copper, which in Solution has the ame Effect; and proves that the Ziment or vitriolic Water, o famous for its uppoed Virtue, of turning Iron into Copper, is no other than a blue Vitriol in a fluid State, becaue upended in too large a Quantity of aqueous Matter; perhaps, indeed, containing Particles of many other Kinds, but evidently owing its characteritic Quality, to Particles of Copper, in a State very nearly reembling that of blue Vitriol, though at preent in Solution.

That the natural Colour of Solutions of Copper in the vitriolic Acids is blue, is evident from only leaving a Drop of any of them on a Plate of Copper, which is preently covered with blue Crytals: And any one a little acquainted with Chemitry will know, that no Difference is to be expected in Solutions made with Oil of Sulphur from thoe with Oil of Vitriol; for thee Acids differ carce enibly when both well rectified, and indeed appear, on trict Examination, to be really the ame Thing;