,! 
' Anal^fis of the Air. 241 
rofe within two inches of a and covered 
the other open end of the fhort fyphon, 
which was deprefled for that purpofe. Over 
this orifice I placed a large inverted chymi- 
cal receiver full of water 5 and over the 
other leg 5- of the great fyphon, I whelmed 
another large empty receiver, whofe capacity 
was equal to 12^4 cubick inches ; the mouth 
of the receiver being immerfedin the water, 
and gradually let down lower and lower b^ 
an afliftant, as the water afeended in it. Then 
Hopping my noftrils, I drew in breath at ay 
thro* the fyphon from the empty receiver: 
And when that breath was expired, the val- 
ve hi flopping its return down thro* the fy- 
phon, it was forced thro* the valve r, and 
thence thro* the fmall leaden fyphon into 
the inverted receiver full of water, which 
water defeended as the breath afeended. In 
this manner I drew all the air, except 5 or 
6 cubick inches, out of the empty receiver at 
Oy the water at the fame time afeending 
into it and filling itj by which means all 
the air in the empty receiver, as alfo all the 
air in the fyphon 0 s by was infpired into 
my lungs, and breathed out thro* the valve 
r into the receiver, which was at firft full 
R , of 
