7o Dr. Wall on the Origin of the 



Of thefe two opinions, that which infinuates 

 that the alkali exifts in vegetables in its perfedl 

 ftate, can hardly be admitted, at leaft until we 

 have accumulated a larger colledion of fafts 

 relative to this point. It is much more proba- 

 ble that the alkali, wherever it is found, whe- 

 ther in confequence of combuftion or otherwife, 

 is formed by fome tranfmutation (if I may be 

 allowed the exprefTion) of the native acid of 

 plants, or by a particular combination of it with 

 the earthy and inflammable principles. 



I am inclined to adopt this doctrine, from the 

 three following circumftances, the two laft of 

 which will alfo fliew, that this tranfmutation may 

 be effedted without combuftion, and therefore, 

 that this alkali cannot be any longer confidered 

 as the creature or offspring of fire. 



Firft Thofe vegetable fubftances, which con- 

 tain the largeft portion of the native acid, afford 

 the larcreft quantity of alkali by incineration : 

 and the quantity of alkali obtained is very con- 

 fiderably increafed by particular modes of apply- 

 ino- the heat, which can only be underftood to 

 operate, by bringing the feveral component prin- 

 ciples of the vegetable fubftance into clofer con- 

 tafl and within the fphere of each other's adion. 



Secondly, This alkali is produced in a very 

 confiderable quantity by the procefs of fermenta- 

 tion to which only the faccharine and acefcent 

 parts of plants are liable. And, 



Thirdly, 



