extracted from different Kinds of Waters. 441 
If the waters deprived of air are expofed to common 
air held in receivers in contact with quickfilver, the air 
which remains unabforbed is fo much more pi 
cated as a lefs quantity of it remains in the rec 
This experiment deferves confideration. 
By means of pure water, efpecially diftilled water, 
common air may be changed into dephlogifticated air, 
that is, into air much more falubrious than the beft com- 
mon air which we breathe; and this, for what I know, 
is the only means of meliorating common air : for all the 
artificial methods (great numbers of which I have tried) 
have proved either ufelefs or noxious, but never fuch as 
promifed to be of any great utility to human kind. 
Though I have long thought of applying thofe expe- 
riments to fome ufe for the purpofes of life, the want of 
time and a proper apparatus has hitherto hindered my 
doing any thing ; 1 now begin to be in hopes I fir all be 
able to do fomething. In the mean time I think it of 
fome importance to have it known, that water not only 
poffelTes the property of diminifhing the noxious part of 
tainted air, but has alfo the power, and that in a very 
high degree, of dephlogifticating common air; which 
muft certainly be one of the methods by which nature 
keeps the atmofphere in a ftate conftantly fit to fupport 
animal life, it being certain, that the water in various 
circumftances 
