1 8 1 Analyjis of the i Ah. 



Experiment LXVII. 



By the farne means alfo, I found plenty 

 of air might be obtained from minerals. 

 Half a cubick inch, or 158 grains of New- 

 caftle coah yielded in diflillation 180 cu- 

 bicle inches of air, which arofe very fa ft 

 from the coal, especially when the yel- 

 lowiih fumes afcended. The weight of this 

 air is 51 grains, which is nearly -§■ of the 

 weight of the coals. 



Experiment LXVIII. 



A cubick inch of frefh dug untried Earth 

 eff the common, being well burnt in diflil- 

 lation, produced 43 cubick inches of air. 

 From Chalk alfo I obtained air in the fame 

 manner. 



Experiment LXIX. 



From a quarter of a cubick inch of An- 

 timony> I obtained 28 times its bulk of air. 

 It was diftilled in a glafs retort, becaufe it 

 will demetalize iron. 



Experiment LXX. 



I procured a hard, dark, grey Pyrites, a 

 "jitriolick miner aljubftance, which was found 



7 feet 





