154 



CAliBON DIOXIDE IX EXPIRED ALYEOLAU AlR, 



Table iii. 



The analyses show the percentage of carbon dioxide in tlie 

 two successive samples taken near the mouthpiece, and the two 

 samples withdrawn at 175 cm. and 200 cm. from the mouthpiece. 

 Tlie samples farthest from the mouthpiece were taken first. The 

 volume of the tube, to the outlet at 200 cm., was 625 c.c. ap- 

 proximately. These analyses show that the percentage of carbon 

 di(jxide in the air along the tube was constant for the distance 

 tested. Such differences as do appear in the figures are within 

 the error of analysis. In the first five experiments, the percent- 

 age of carbon dioxide was varied between 2*7 and 4*1. In tlie 

 sixth expei'iment, the percentage of carbon dioxide was 32. In 

 the second series of experiments, recorded in Table i v., the volume 

 of the gas driven into the tube was measured. This was found 

 necessary, as the brief release of the spring-clamp did not permit 

 of the wliole of the couipressed gas passing into the tube. 



Table iv. 



No. of 

 expt. 



Volume of gas Volumes to which 



passed through the gas was com- 



tube in c.c. pressed in c.c. 



800 

 TOO 

 11 -lo 

 1150 

 KKM) 

 1200 

 1300 

 1200 



1 l(KjO-8750 

 11250-8750 

 ll(MX)-9750 

 11250-8750 

 11250-8750 

 10750-8750 

 11250-8750 

 115(M)-8750 

 11500-8750 



Pejcentage of COo in samples of 

 the gas collected at distances 

 from the mouthpiece of 



200 cm. 



34 6 

 23 -6 

 14-2 

 23-4 

 15 -6 

 21-5 

 13-3 

 9-3 

 6-0 



