Jnalyjls of the Air. 243 

 lungs is much mote capacious than 226 cu- 

 bick inches; for Dr. Jurzn, by an accurate 

 Experiment, found that he breathed out, at 

 one large expiration, two hundred and twenty 

 cubick inches of air; and I found it nearly 

 the fame, when I repeated the like Experi- 

 ment in another manner: So that there mufl 

 be a lar^e allowance made for the bulk of the 

 remaining air, which could not be expired 

 from the lungs; and alfo for the fubfbnce 

 of the lungs. 



Suppofing then, that, according to Dr.y#- 

 riris eft i mate, (mMctfs Abridgment of the 

 Philofophical Tranfacl. Vol. I. p. 415.) we 

 draw in at each common infpiration forty 

 cubick inches of air, that will be 48000 cu- 

 bick inches in an hour, at the rate of twenty 

 infpirations in a minute. A confiderable pare 

 of the elafticity of which air is, we fee by 

 the foregoing Experiment, conflantly de- 

 ftroyed, and that chiefly among the veficks, 

 where it is charged with much vapour. 



But it is not eafv to determine how much 

 is destroyed. I attempted to find it out by 

 the following Experiment, which I (hall here 

 give an account of, tho 7 it did not tucceed 

 fo well as I could have wifhed, for want of 

 much larger veflels ; for if it was repeated 



R 2 with 



