[ 230 ] 
air extradled in the above-mentioned procefs) was 
found to weigh eight ounces, two drachms, fifty 
grains. So that the bulk of the air extradled from 
the Pouhon water was to the bulk of the water from 
which it had been extradled, nearly as 84 to 204. 
Or, if we choofe to reduce the above quantities into 
cubic inches, and allow a cubic inch of water to 
weigh 265 grains, we fliall find, that in this procefs 
cubic inches of air were extradled from 
37445 cubic inches of the Pouhon water. 
From the above experiment it appears, that a very 
large quantity of air is contained in the Pouhon wa- 
ter : and a way is pointed out whereby the propor- 
tion of the bulk of air to that of a certain quantity 
of water, from which it had been extradled, may be 
exadlly determined. Altho’ this proportion mu ft vary 
confiderably in many waters, according to the weight 
and heat of the atmofphere, or the drynefs or moi- 
fture of the feafon, at the time that they are taken 
from the fountain j and will alfo vary with the dif- 
ferent degrees of expanlion of the atmofphere, at the 
times that the different quantities of air are meafured j 
I do not, therefore, give the above proportions for 
fuch as always hold ; neither do I ^ert that they 
moft commonly take place. I rather fufpedl the 
contrary j and, from other trials, am apt to believe, 
that a larger proportion of air is ufualiy contained in 
the Pouhon water, than that which I obtained in 
the above experiment. For, when a boiling heat 
was ufed, the necks of the bladders were apt to fliri- 
vcl, and became liable to crack on the leaft motion ; 
lb that it was difficult to confine the air in them. 
Flad I had an opportunity at Spa of profecuting this 
experiment 
3 
