24 ^ Anahfis of the Air. 
of water. I marked the boundary of air 
and water,' and then immerfed the whole 
receiver, which had the breath in it, under 
water, and there gradually poured the con- 
tained breath up into the other full receiver, 
which flood inverted over o s ; whereby I 
could readily find, whether the air had lofl 
any of its elaflicity : And for greater furety, 
I alfo meafured the bulk of breath by filling 
the receiver with a known quantity of water 
up to the above mentioned mark 5 making 
alfo due allowance for a bulk of air, equal 
to the capacity of the large fyphon 0 s by 
which was at lafl fucked full of water. 
The event was, that there was 1 8 cubick 
inches of air wanting ; but as thefe receivers 
were much too fmall to make the Experi- 
ment with accuracy j that fome allowance 
may be made for errors , I will fet the lofs 
of claftick air at 9 cubick inches, which is 
but Tfe whole air refpired, which 
will amount to 353 cubick inches in one 
hour, or 100 grains, at the rate of 4S000 
cubick inches infpired in an hour, or one 
ounce and a half in twenty four hours. 
By pouring the like quantity of air to and 
fro under water, I found that little or none 
of 
