96 



Composition of the Atmosphere 



Table 57. Analyses made at the Nutrition Laboratory of air confined in a steel cylinder. 



Series 2. 



EFFECT ON OXYGEN ABSORPTION OF HIGH AND LOW TEMPERATURES. 



An examination of the results in table 57 shows an approach to con- 

 stancy, but the variations are still too wide to be permitted in this study. 

 During this period it is seen that the temperature of the water-bath had 

 a wide variation, ranging from 16.1 C. to 32.2 C. Owing to the fact that 

 a number of investigators with w r hom I had conferred in a recent European 

 tour had suggested that the absorption of oxygen might be profoundly 

 affected by changes in temperature, the wide range was artificially pro- 

 duced for the special purpose of studying this particular point. From 

 the data in table 57 the volumes for the various temperatures have been 

 rearranged so as to give the average results at approximately an average 

 temperature. These results have been incorporated in table 58. An ap- 

 parently constantly decreasing percentage of carbon dioxide is not con- 

 sidered here, since subsequent experiments show that the decrease is not 

 an inevitable accompaniment of increased temperature. The oxygen de- 

 terminations show a difference of 0.01 per cent between the value at 

 17.1 C. and that at 25.8 C, but an insignificant difference between the 



