PHYSICAL AND LITERARY. SjTj: 



nerated nitre, in this manner: I took two 

 ounces of an extemporaneous fixed alca- 

 line fait, made of equal parts of nitre and 

 tartar ; I diffolved this fait in warm wa» 

 ter, filtred the folution, and poured into 

 it fhrong fpirit of nitre, a little at a time, 

 until the alcaline liquor was perfeclly fa- 

 tiated with the acid, which required one 

 ounce and a half of the Ipirit pf nitre. 

 From this faline liquor, by evaporation 

 and chryftalhzation, I procured two oun- 

 ces and a half of fait, when it was all 

 colleded and well dried. Ihe chryitals 

 were long, flender, and prilrnatiqal ; the 

 fait had a pretty mild and cooling tafle ; 

 and bits pf it put upon a buri>ing coal 

 made it fpaikle and give a bright flame. 



We may obferve by the way. that the 

 compound fait exceeded the weight of the 

 fixed fait by half an ounce or 240 grains; 

 this additional weight it procured froni 

 the fpirit pf nitre : Therefore one ounce 

 and a half, or 720 grains of the fpirit of 

 nitre which I ufed, contain 240 grains of 

 true acid, which is capable to fatiate tour 

 times its weight pf alcaline fixed fait, 



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