DURING THE MIDDLE AGE. 131 



the acid were found in a fcparate ftate, it would 

 be either impoflible, or beyond the powers of 

 chemiftry to faturateit with phlogiilon. 



The alchemilis contend, that the principle 

 of gold, though corrupted by various caufes, is 

 contained in all the metals ; and that, if proper- 

 ly purified and freed from extraneous matter, 

 it may be brought into its perfect ftatc. From 

 what has been faid before, then, this is as much 

 as to declare the original acids of all metals to 

 be the fame; from which, cither by varying tho 

 proportion, or by the admixture of heterogene- 

 ous fubftances, nature produces fuch dirtcrent 

 effects, that, by the addition of a certain quan- 

 tity of phlogifton, according to the capacity of 

 the fubftance, not only gold, but various kinds 

 of metals are in the ufual manner produced. 

 To correct the errors of thcfe proportions and 

 combinations, by the means of their elixir, or 

 philofopher's ftone, was the great aim of the al- 

 chemifls; fo that all the bafcr metals might be 

 converted into gold, or, in their own language, 

 to tinge the imperfect, in fuch a manner, as to 

 render them all the moft perfect of metals. 



If we attend to the experiments hitherto 

 known, and made with the greateft care, we 

 fliall find but little or no encouragement to be- 

 lieve in the tranfmutation of metals or other 

 more fimple bodies. In thofc days, when the 

 inveftigationof philofophcrs were not made with 

 I 2 the 



