252 On the Alhaliex of Comrnercg. 



may seem at first view more natural, I think we ought to 

 prefer that derived from the principles of the nomenclature, 

 from which we cannot depart without replunging the lan- 

 guage of chemistry into the confusion from which it has 

 been so happily extricated : in fact, the carbonates of potash, 

 soda, and an)nionia, are alkaline carbonates, however neutral 

 they may be: the denomination of alkalescent carbonate is 

 not more proper, because this would indicate a successive 

 diminution of the proportion of acid. The salt in question 

 cannot therefore be called any thing else than supersatu- 

 rated carbonate of potash. 



Uncertainty of the Processes for the Cau'^ifcal'ion. of the 

 AlUalies. 



T return to the caustification of the alkalis by lime : there 

 can be no doubt as to the uncertainty which prevails on this 

 subject, even in tlie most recent treatises in chemistry : I 

 shall quote only one example among all those I might col- 

 lect. We read in the Si/stcvie des Cannoissances Ch'imicjues, 

 by M. Fourcroy, sect. iv. art. 10. no. 4, that " hi order to 

 obtain pure potash ice must mix it with double its weight of 

 limey and eight or ten times the weight of the total mixture 

 of rain water', we must boil them for two or three hours, filter 

 and draw off the clear lixivium, this we must try by lime 

 water, which it ought not to precipitate ; otherwise ive should 

 again pass it over quicklime." On the other hand, •con-, 

 suit sect. v. art. 12. no. 16, and you will find what fol- 

 lows : " we must mix the carbonate rf potash with half its 

 weight of quicklime, upon which it must be strewed." Water 

 should then be thrown over it in order to slake the lime; it 

 is afterwards diluted j it absorbs carbonic acid ; it passes to 

 the state of carbonate of lime, which is insoluble, and the 

 potash remains pure and caustic in the liquor." 



[To hi coatinueJ.] 



,XXXIV. Re- 



