Fixed Vegetable Jlkali, &c, 75 



III. The vegetable alkali feems alfo to be, 

 in fome inftances, generated or formed by 

 putrefadlion ; for nitre, of which it is an eflen- 

 tial part, is often the product of a putrefadivc 



procefs. 



It has long been a received do<51:rine in che- 

 miftry, that the nitrous acid owes its origin to 

 putrefaflion : but that the alkali of nitre is 

 derived from that fource, may appear a novel 

 opinion; and yet it is deduciblc from the lately 

 obfervations, which have been made relative to 

 the generation of nitre. 



When it was firft related by travellers from 

 the Eafl: Indies, that nitre was there found on 

 the furface of the ground, perfeflly formed ; and 

 that it was fwept up and collected for ufe, 

 without any other preparation ; the account was 

 confidered in Europe, as at lead erroneous, and 

 derided as inconfiftent with the moft eftablifhed 

 fads, concerning the formation of this fait. It 

 was alledged that nitre, v;herever produced by 

 any thing like a natural procefs, is always im- 

 perfccV, having a calcareous, inflead of an alka^ 

 line bafc ; that to make it perfedt, a frefh folu- 

 tion, with the addition of wood-afhes, was in- 

 difpenfably requifite, both for its purification, 

 and to fupply the vegetable alkali. This, in 

 particular, was the language of Neumann,* ^ 



* Neumanns Chemiftrf, by ^^w/V, Oftavo, Vol. I. p. 306. 



chemifl: 



