14 *flx Principles of Part I. 



BUT we have a certain method of know- 

 ing, whether a body contains any oleagi- 

 nous particles or not, by the means of nitre 

 melted in the fire. Nitre, though not in- 

 flammable of itfelf, becomes, in this fitua- 

 tion, inflammable, or, as the chymifts 

 chufe to call it, deflagrates with bodies 

 which contain any oily particles. 



Exp. i. Some rich mould taken up three 

 or four inches deep from the border of a 

 garden where no dung had ever been laid, 

 deflagrated very much with nitre in fufion. 

 Hence it appears, that this foil contains 

 much oil. 



To difcover if this earth contained any 

 abforbent or alkaline particles, I tried the 

 following experiment. 



Exp. 2. Some ftrong vinegar, diluted 

 with twice its quantity of water, being 

 poured on this fat earth* raifed a gentle fer- 

 mentation, from whence many air-bubbles 



arofe ; 



