Chap. 4.] Suppofed fr an/mutation of Metals. 19 



The fluid will, however, remain perfectly clear, the 

 particles being fo extremely minute, that the rays of 

 light will fuffer no interruption in paffing through 

 them. If, however, to this folmion of filver a quan- 

 tity of mercury or quickfilver is added, the aqua for- 

 tis will be attracted by the mercury, and the filver will 

 be precipitated, or thrown to the bottom of the veflei 

 in which the fluid is contained ; if, again, copper is- 

 added, it will affume the place of the quickfilver, and 

 if to this folution of copper a bright piece of iron (for 

 ruil would exclude the acid from coming in contact 

 with the metal) is introduced, the acid will imme- 

 diately quit the copper and feize upon the iron, a 

 quantity of which being diffolved in the fluid, the 

 cop'per will be depofited in its place on the furface of 

 the bar of iron *. The iron may afterwards be dif- 



placed 



* ' This experiment explains to us, in a very fattsfaftory manner, 



' the nature of" that tranfmutaticn of iron into copper y which travellers 



' have been fo much furprized at. Agricola fpeaks of waters in 



' the neighbourhood of Neivfol, in Hungary, which had the pro- 



' petty of tranfmuting the iroa which was put into them into cop- 



' per f - In the year 1673, our countryman, Dr. Brown, vifited a 



' famous copper mine at Herrn-Grundt, about feven Englifh miles 



' from Ne-ivfel; he informs us that he there fawtvvo fprings, called 



' the old and new ziment, which turned iron into copper. This 



' workmen fnewed him a curious cup made of this tranfmtited 



' iron 4 it was gilt with gold, had a rich piece of filver ore faften- 



* ed in the mickile, and the following infcription engraven on the 



' outfide: 



' Eifen ware icb, kupfer bin icb, 

 ' Silver trag ich, gold bedeckt mich, 



' Copper I am, but ircn was of old, 



' Silver I carry, covered am with gold J, 



It was even at that time, he fays, contended by fome, that there ' 

 ' was no real tranfmutation of iron into copper, but that the 



f Agnc. Fof. L. ix. p. 347. 



\ Brown's Travels, ed. 1687, p. 69* 



C 2 * z'roent 



