131 



Metabolism of Healthy Man. 



Summing up all of the results, we find that with 18 subjects with food the 

 average pulse-rate was 66, and with 12 subjects without food the average was 

 62. Comparing the subjects with whom experiments were made both with and 

 without food, we find that with the 12 subjects the average pulse-rate was 

 approximately 62 per minute without food, while with food the average pulse- 

 rate per minute was 64, an inconsiderable increase. 



Table 52. Average pulse-rate in experiments with different subjects with and 



tcithout food. 



COMPARISON OF PULSE-RATE AS DETERMINED BY DIFFERENT METHODS. 



Since in a very large number of experiments the subjects counted the pulse 

 themselves, it is important to determine to what extent one can rely upon the 

 pulse-rate counted by a subject inside the respiration chamber as indicating 

 the true pulse-rate. For purposes of comparison, a number of experiments 

 were made in which the subject counted his own pulse-beat and simultaneous 

 observations were made outside of the chamber by an attendant, either by 

 means of a pneumograph or, very recently, by a stethoscope. This series of 

 experiments was somewhat extended in nature and was made with 10 subjects. 

 The results are collected for comparison in table 53. 



While there are fluctuations both ways, in general it appears that the count 

 as registered by the subject is apt to be somewhat lower than that obtained 

 from the pneumograph. Whether the rate is actually decreased while the 

 subject is counting the pulse, or whether the lower figure is obtained by error 

 in counting we can not as yet tell. In the experiments made in 1908 and 

 1909, recorded in table 53, the results show likewise wide differences, although 

 here, with the exception of the subject F. E., the pulse-rates as counted by 

 the subject were invariably somewhat higher than those indicated by the ap- 

 paratus. We are inclined to consider the low figures obtained by F. E. on 

 himself in the experiment of December 15 and December 21, as due to inex- 

 perience in counting the pulse. These latter experiments, then, would imply 

 that the differences noted in the preceding portion of the table were due not to 

 an actual difference in the pulse-rate so much as to inabilit}*- on the part of 

 the subject to count the pulse carefully. 



