OF FOSSILS. 



} XL. Docs not determine the Proportion of the 

 different Principles. 



AND laflly, if fomctimes it is competent to dif- 

 cover fmglc principles, yet it always conceals 

 their mutual proportions. This imperfection is 

 of the greater moment, as it is evident, that the 

 proportions of the fame materials being varied, 

 both the appcarencc in the fire, and the other qua- 

 lities of the foflil, arc often conlidcrably altered, 



5 XLI. Merit ofCronfledt. 



THE celebrated Cronilcdt, in his excellent fy- 

 ftcm of follils, has eflablifiicd the fuperiority of 

 principles, and has therefore conceived the ge- 

 nuine method ; and if, notwithstanding, he has 

 occailonally fallen into errors, they muft be at- 

 tributed to the want of proper experiments. 



XLI i. The left Method of examining Foffds in 

 the Humid IV ay. 



THE illuftrious Margraf had no fooncr difco- 

 vcred the true method of decompofition, the hu- 

 mid and menflrual, than he endeavoured, by his 

 own exertions to render it cafy and practicable. 

 The new road into which he ftruck, was bcfet 

 with thorns and briars ; but it is certainly the 

 P only 



