BED CALORIMETER AND TENSION-EQUALIZER UNIT. 109 



An inspection of the data given in table 13 shows that in many of 

 the comparisons the differences between the results obtained with the 

 two forms of apparatus are considerable. With the values for the car- 

 bon-dioxide production, it will be found that in 24 out of 39 comparisons 1 

 the average values with the respiration apparatus varied more than plus 

 or minus 5 c.c. per minute; in only 6 of these experiments was the carbon- 

 dioxide production higher with the respiration apparatus. 



Adopting the same limits of difference with values for the oxygen 

 consumption, we find that in 30 experiments this factor varied more 

 than plus or minus 5 c.c. per minute; in 20 of these experiments the 

 values are greater with the respiration apparatus. 



The respiratory quotient shows differences greater than plus or 

 minus 0.04 in 18 experiments; in only 2 of these experiments was this 

 value higher with the respiration apparatus. 



The differences in the values for the pulse-rate varied somewhat 

 widely, but not much stress can be laid upon them, owing to the diffi- 

 culty in making records of the pulse-rate in the bed calorimeter. It 

 must be pointed out that unless the records of the pulse-rate are suffi- 

 ciently frequent to represent a true average, the averages can not be 

 used as possible indications of differences in the respiratory exchange. 



If each comparison is considered as a whole, the following may be 

 accepted as giving comparable results with the two apparatus: T. M. 

 C, all experiments; J. J. C, November 3 and 15; V. G., November 4; 

 the one experiment with L. E. E. ; H. F. T., August 31, first experiment; 

 the one experiment with I. A. F.; S. A. R., April 5; and P. F. J., March 

 29. In addition to these there are nine other experiments in which the 

 respiratory quotient shows good agreement. As pointed out previ- 

 ously, the primary cause in the differences in the values for the carbon- 

 dioxide production and oxygen consumption is the difference in the 

 muscular activity, while it is believed that the primary cause of the 

 differences in the respiratory quotient is the difficulty of measuring 

 correctly the oxygen consumption in the bed calorimeter. 



An extraordinarily good opportunity for comparing respiratory 

 quotients obtained with the bed calorimeter and the Benedict respira- 

 tion apparatus presented itself in the measurement of the respiratory 

 exchange of a man who fasted for 31 days. Such a comparison is 

 made in table 14, which shows the respiratory quotients obtained each 

 night while the subject was in the bed calorimeter and the respiratory 

 quotients obtained with him immediately after he was removed from 

 the chamber. 2 The quotients given for the bed calorimeter are values 

 for the entire night period, i. e., from about 10 p. m. to 7 a. m., while 

 those given for the respiration apparatus are the averages of three 



'While there were only 36 experimental days, it is considered that on three of these days two 

 individual comparisons were made. 



*The experiments in the morning were with the spirometer unit. 



