222 



COMPARISONS OF RESPIRATORY EXCHANGE. 



Average barometric pressure, 769.6 mm. ; average temperature of air in appa- 

 ratus, 18.3 C. 



J. K. M., March 14, 1913. With automatic counterpoise, 3 periods; 

 without automatic counterpoise, 3 periods; preliminary period, 36 minutes; 

 periods with and without counterpoise alternating. Counterpoise tube half 

 full of water and no water running in siphon. The sample of air taken for the 

 second period (without counterpoise) was not properly closed and it was 

 contaminated with outside air; the results obtained for the carbon-dioxide 

 production and oxygen consumption for this period are therefore too low. 

 Pulse-rate uniform in all periods. Average respiration-rate in preliminary 

 period, 20 per minute; between periods, 16, 17, 17, and 17 per minute, respec- 

 tively. During the experimental periods the rate was uniform, but it was 

 not possible to judge of the character of the respiration, owing to the fact that 

 the pneumograph did not give a clear record. Subject stated that there was no 

 resistance of any kind to the respiration. Average barometric pressure, 759.8 

 mm.; average temperature of air in apparatus, 16.5 C. 



DISCUSSION OF RESULTS. 



The results of the experiments with the Tissot apparatus, in which 

 the respiratory exchange with and without the counterpoise was com- 

 pared, are given in table 41. The average values for all of the factors 

 measured practically agree with the two methods. 



The variations between the averages for each method in the individ- 

 ual experiments are shown in table 42, the values for the experiments 

 with the counterpoise being used for the base-line. These difference- 



iparatus with 



TABLE 41. Respiratory exchange in comparison experiments unth the Tissot appai 

 and ivithout automatic counterpoising of the spirometer bell. {Without food. 



