ZUNTZ-GEPPERT AND BENEDICT METHODS. 



127 



sons. The average variation is 12 c.c. for the carbon-dioxide produc- 

 tion, 10 c.c. for the oxygen consumption, and 0.045 for the respiratory 

 quotient. 



An examination of the statistics shows that there was more or less 

 variation in the conditions during experimenting. A few comparisons, 

 however, show results for each apparatus which are, on the whole, 

 entirely comparable, as, for example, the experiments with T. M. C, 

 A. G. E., L. E. E. (July 14), and D. J. M. The averages for D. J. M. 

 are not in close agreement, but if the periods are arranged in the order 

 in which they were carried out it will be seen that the results give 

 slowly descending values independent of the apparatus. This subject 

 had been somewhat active previous to the experiment in running on 

 errands and was accordingly not in the best of condition for such 

 observation. The largest differences between the two apparatus are 

 shown by the subject J. J. C, these being both plus and minus. This 



Table 18. — Variations of average results obtained with the Zuntz-Geppert apparatus from those 

 obtained with the Benedict respiration apparatus {tension-equalizer unit). 



subject was most difficult to control because of his inability to keep 

 awake; in all probability the variations are due more to differences in 

 wakefulness rather than to actual differences in the method of deter- 

 mining the respiratory exchange. An examination of the pulse-rate 

 tends to confirm this, as the records show somewhat wide variations for 

 the individual periods. The pulse-rate in the comparisons with other 

 subjects also shows somewhat wide variations. As the differences in 

 this factor are both plus and minus, there is no evidence that the pulse- 

 rate is higher with one apparatus than with the other. 



The percentage of uniformity in the results with the two apparatus 

 has also been calculated for this comparison and used as a basis for 

 plotting probability curves. (See fig. 38.) These curves show that 

 the general uniformity is practically the same with both apparatus, 



