MOUTH- AND NOSE-BREATHING, BENEDICT APPARATUS. 179 



opportunity for compensation. The general indications are, however, 

 that the respiration-rate and the respiratory quotient were practically 

 the same with both methods of breathing. 



The probability curves plotted from the variations of the individual 

 periods from the average are given in figure 47. The pulse-rate and the 

 oxygen consumption are slightly more uniform with mouth-breathing 

 than with nose-breathing, but the respiratory quotient is more uniform 

 when the nosepieces are used. In general, there appeared to be no differ- 

 ence in the respiratory exchange with the two methods. Consequently 

 either mouthpiece or nosepieces may be used with the tension-equalizer 

 unit without affecting the results. 



CAPMN DiOXIDE EL>M<NME 



RER..CEN.T. OF VARIATION 



FIG. 47. Probability curves for the series of comparison experiments with nose- and mouth- 

 breathing (tension-equalizer unit). 



The ordinates indicate the percentage of the total number of periods and the abscissae the 

 percentage of variation from the average. 



MOUTH- AND NOSE-BREATHING WITH THE BENEDICT RESPIRATION APPARATUS 

 (SPIROMETER UNIT). 



In the results previously given of a series of comparison experiments 1 

 it was shown that the respiratory exchange with the two forms of the 

 Benedict respiration apparatus the tension-equalizer unit and the 

 spirometer unit was essentially the same, but in those experiments 



'See p. 111. 



