78 A TREATISE ON THE CONNECTION OF 



whilst the carbonic acid, or fixable air, will combine with 

 the vegetable alkali^ forming mild alkali, or carbonat of 

 potash. 



Mnch of the oxalat of lime will be formed, by adding 

 calcareous matter to ground abounding with plants of 

 sorel, or other vegetables containing the soreline or oxalic 

 acid ; by which application, the vegetable alkali will be 

 disengaged in a carbonated or mild state. From the in- 

 solubility of oxalat of lime, it is not probable that it can 

 contribute, per se, to the food of plants. It cannot be 

 decomposed by alkalis, on superior affinity, because its 

 affinity is greater with calcareous matter ; but it may be 

 decomposed by the vitriolic acid, in which case, gypsum 

 will be formed, and the soreline, or oxalic acid, thus dis- 

 engaged, will be capable of entering into new combina- 

 tions with fixed, or volatile alkaline salts, or magnesia. 

 These combinations are sokible, and, when not super- 

 .acidulated, promote vegetation in a high degree. 



Oxalat of lime may probably be decomposed by 

 certain" neutral salts, on the principles of the double 



elec- 



