ON VEGETABLE ACIDS 277 



distillation, enipyreumatic acid of tartar and a spongy coal. 

 Hence it appears that spirit of wine consists of acid of 

 tartar, of water, and phlogiston ; so that it is a native 

 dulcified acid ; and nitrous acid, on being mixed with it in 

 moderate quantity, dislodges the acid of tartar. If more 

 nitrous acid be added, the acid of tartar is converted into 

 acid of sugar and phlogiston ; and by adding a new portion 

 of nitrous acid the acid of sugar is changed into vinegar. 



(7) If one part of acid of sugar, together with one 

 and one-half part of manganese, be boiled with a sufficient 

 quantity of nitrous acid, the manganese will be almost 

 entirely dissolved, and vinegar, with phlogisticated nitrous 

 acid, pass over into the receiver. 



(8) If acid of tartar and manganese be boiled with 

 vitriolic acid, the manganese will be dissolved, and vinegar, 

 with vitriolic acid, be obtained. 



(9) When acid of tartar, manganese, and nitrous acid 

 are boiled together, the manganese is dissolved, and vinegar, 

 together with phlogisticated nitrous acid, is obtained. 



(10) If acid of tartar and spirit of wine be digested 

 together for several months, the whole is converted into 

 vinegar, and the air in the vessel becomes partly fixed and 

 partly phlogisticated air. 



(11) If spirit of wine be boiled with vitriolic acid and 

 manganese, it will be converted into vinegar and phlogistic- 

 ated air. 



(12) Spirit of wine, by being distilled upwards of twenty 

 times from off caustic alkali, was changed into vinegar, and 

 a considerable quantity of water was obtained. 



Hence it follows that the acids of tartar and sugar and 

 vinegar are modifications of the same acid, as it contains 

 more or less phlogiston. The acid of tartar has the greatest 

 quantity ; the acid of sugar, a little less ; and vinegar has 



