relating to Air and Water „ 281 
began with this, with a view to afeertain whether any water 
is produced when the air is made to difappear in it. Accord- 
ingly, into a glafs veil'd containing 7 ounce meafures of pretty- 
pure dephlogifticated air, I introduced a quantity of iron turn- 
ings (which is iron in fmall thin pieces, exceedingly conve- 
nient for thefe and many other experiments) having previouily 
made them, together with the veffel, the air, and the mercury 
by which it was confined, as dry as I poffibly could Alfo, to 
prevent the air from imbibing any moifture, I received it imme- 
diately in the veffel in which the experiment was made, from 
the procefs of procuring it from red precipitate; fo that it had 
never been in contad with any water. 
I then fired the iron, by means of a burning lens, and pre- 
fently reduced the 7 ounce meafures of air to .65 ; but I found no 
more water after this procefs than I imagined it had not been 
poffibie for me to exclude, as it bore no proportion to the air 
which had difappeared. Examining the refiduum of the air, I 
found one-fifth of it to be fixed air, and when I tried the purity 
of that which remained by the teft of nitrous air, it did not 
appear that any phlogifHcated air had been produced in the pro- 
cefs : for though it was more impure than I fuppofe the air 
with which I began the experiment muft have been, it was not 
more fo than the phlogifticated air of the 7 ounce meafures, 
which had not been affedted by the procefs, and which muff 
have been contained in the refiduum, would neceffarily make 
it. In this cafe one meafure of this refiduum and two of ni- 
trous air occupied the fpace of .32. 
In another experiment of this kind, ten ounce meafures of 
dephlogifticated air were reduced to .8, and by wafhing in lime 
water to . 3 8. In another experiment, in which "j\ ounce mea- 
fures of dephlogifticated air were reduced to half an ounce 
Vgl. LXXV. O o meafure. 
