kii PREFACE. 



rience evinces, that nature is ftill more varied 

 than his descriptions.* But where any new 

 fubftance occurs, or an intire certainty re- 

 quired, fuchas conftitutes the foundation of a 

 Jcience, there chymical tefts are abfolutely re- 

 quifite, and alone fufficient. Thus negle&ing 

 thefe, Mr. Rome de Lljle took that to be a 

 zeolyte which Mr* P die tier afterwards found 

 to be an ore of zinc. 2 Cryjlallogr. p. 46, 

 2O Roz. 424. 



Mineralogy mufl therefore, on the whole, 

 be confidered as a branch of Chymiftry, and 

 its progrefs, like that of other branches of 

 that fcience, has been for many ages fcarce 

 fenfible. In the earlieft times, of which we 

 have any account in hiftory, mankind feern 

 to have been of the fame turn of thinking as 

 the lefs enlightened and civilized nations of 

 our own age. Satisfied with fuch informa- 

 tion as cafual experience threw in their way, 

 they regarded the occupation of confulting na- 

 ture by experiment as a childim, trifling and 

 ufelefs amufement, and neglected forming 

 any theory whatfoever concerning its opera- 

 tions ; but in fucceeding times the gene- 

 ralizing fpirit of Ariftotelic Metaphyfics ex- 

 tending itfelf to Natural Philofophy, foon 

 fuggefted the notion of one common matter 



* See Ron. journal for March, 1784^,206, 207, and 211. 



being 



