244 Analyfis of the Air. 



with more capacious veffels, it would deter- 

 mine the matter pretty accurately 5 becaufe 

 by this artifice frefh air is drawn into the 

 lungs at every infpiration, as well as in the 

 free open air. 



Experiment CX. 

 I made ufe of the fyphon (Fig. 39.) take- 

 ing away the bladders, and diaphragms i i 

 n no: I fixed, by means of a bladder, one 

 end of a fhorc leaden fyphon to the lateral 

 foffet i i : Then I fattened the large fyphon 

 in a veffel, and filled it with water, till it 

 rofe within two inches of a y and covered 

 the other open end of the {hort fyphon, 

 which was depreffed for that purpofe. Over 

 this orifice I placed a large inverted chymi- 

 cal receiver full of water ; and over the other 

 leg s of the great fyphon, I whelmed an- 

 other large empty receiver, whofe capacity 

 was equal to 1224. cubick inches; the 

 mouth of the receiver being immerfed in 

 the water, and gradually let down lower 

 and lower by an affiftant, as the water 

 afcended in ir. Then flopping my noftrils, 

 I drew in breath at *z, thro' the fyphon from 

 the empty receiver : And when that breath 

 was expired, the valve b i flopping its return 



down 



