ON RESPIRATION. QOl 



per chJ of the tube a should be made conical, and its edges 

 sharp, the better to suffer the papers to pass over it. A 

 section of the tube and female screw b beneath is shown 

 separately at fig. 4. The papers are shown in fig. 2, in the 

 situation they are commonly placed upon the cylinder, with 

 the wire within the cylinder. 



IV. 



On Respiration. 1??/ William Allen, Esq. F.R.S , and 

 William Hasledine Pepys, Esq., F.R.S. 



(Concluded from p. 301.) 

 First Experiment with Atmospheric Air. 

 JL he Guinea pig was placed upon the stand, and the ap- -Atmospheric 



air res|>ired b; 

 a Guinea ing 



paratus arranged as represented in the plate: 250 cubic.^" '^'"'"'^^ ^ 

 inches of atmospheric air were admitted into the mercurial 

 gasometer communicating with B: the gasometer communi- 

 cating with C was quite empty, the apparatus being tried 

 was found perfectly air tight, and the whole qnantity of air 

 310 cubic inches. 



The cocks 11 and I being opened, gentle pressure was 

 made upon the glass of gasometer B, so as to cause the air to 

 pass through A, which consequently drove an equal portion 

 through the tube C into the empty gasometer; a quarter of 

 an hour was employed in' passing the gas, which .measured 

 exactly 250 cubic inches in C, so that there was no alter, 

 ation of volume; the cocks H and I were now closed, and 

 the respired air being examined by the usual methods, 100 

 parts were found to contain 



5 carbonic acid Resultj. 



16 oxigofl 

 79 axotc 



100 

 As the air after the experiment had experienced no alteration 

 of volume, and as it contained (he same proportion of azote 

 as atmospheric air, this substance had remained unaltered. 



But 



