Fixed Vegetahk Alkali, ^c. 73 



peated thefe experiments with the fame fuccefs, 

 I was defirous of obtaining a confirmation of 

 this fa£l, by a different mode; and as I do not 

 remember to have feen the procefs in any che- 

 mical work, I fhall trouble the Society with an 

 account of it. 



I poured, upon an ounce of cream of tartar, 

 nearly a pint of boiling water, and immediately- 

 added two ounces of Glauber's fpirit of nitre, 

 conceiving that the latter, by its ftrong attrac- 

 tion to the vegetable alkali (fo fuperior to that 

 of the acid of tartar) would, if that alkali exifted 

 in tartar, detach it from its union, and form with 

 it a perfed nitrrc. Immediately upon the addi- 

 tion of the nitrous acid, the cream of tartar 

 was diflblved ; much fooner than might have 

 been expeded, from the quantity of water em- 

 ployed ; but the folution was probably expedited 

 by the change which took place upon the addi- 

 tion of the nitrous acid. The mixture was then 

 fet in the heat of a water-bath, and evaporated 

 to the proper degree for cryftallization ; and be- 

 ing then placed in the cold, afforded a dram of 

 well-formed cryflals, which appeared, both by 

 their figure and tafte, and by deflagrating with 

 charcoal, to be perfed nitre.* 



From 



* The quantities of the cream of tartar and fpirit of 

 nitre, ufed in thefe experiments, were taken at random, 

 I >vas only folicitous to employ fo much of that latter, as 



might 



