[ ^8 ] 



lir, winds blowing from different 

 quarters, and conveying airs of dif- 

 ferent qualities, from diftant coun- 

 tries, and many other operations of 

 nature, unnoticed as yet? 



Water itfelf, one of the iimpleft 

 and the moft unalterable fubftanceS 

 known, feems to be changeable 

 into dephlogifticated air, or at leart 

 to contain fome things which may 

 be transformed into this air by 

 the influence of the day-light ; for 

 the green vegetable fubftance, which 

 ferves as a kind of laboratory, in 

 which this falubrious air is produced^ 

 is formed from the water itfelf. 

 Abbe Fontana made a great many 

 experiments tending to examine the 

 air extracted from different waters 

 by heat. I was prefent at thefe 

 experiments in the iummer of 1 7 7 7 ? 

 being then at Paris. He extracted 

 5 from 



