ijS ESSAYS AND OBSERVATIONS 



fomething of the fame kind. The reft is 



air. 



The celebrated Homberg has attempted to 



eftimate the quantity of folid fait contained 

 in a determined portion of the feveral acids. 

 He faturated equal quantities of an alkali with 

 each of them ; and, obferving the weight 

 which the alkali had gained, after being per- 

 fedly dryed, took this for the quantity of fo- 

 lid fait contained in that fhare of the acid 

 which performed the faturation. But we 

 learn from the above experiment, that his efti- 

 mate was not accurate, becaufe the alkali lofes 

 weight as well as gains it. 



Two drams of magtiejia, treated exactly 

 as the alkali in the laft experiment, were juft 

 diftblved by four drams, one fcruple, and fe- 

 ven grains of the fame acid liquor, and loft 

 one fcruple and fixteen grains by the ebulli- 

 tion. 



Two drams of magnefia were reduced, by 

 the adion of a violent fire, to two fcruples 

 and twelve grains, with which the fame pro- 

 cefs was repeated, as in the two laft expe- 

 riments ; four drams, one fcruple, and two 

 grains of the fame acid were required to com- 



pleat 



