152 COMPARISONS OF RESPIRATORY EXCHANGE. 



The statistics of the 17 experiments are given in the following pages. 

 As in the previous comparison, the average barometric pressure and 

 the average temperature of the air in the apparatus are added to the 

 data usually presented. 



STATISTICS OF EXPERIMENTS. 



K. H. A., June 4, 1912. Spirometer unit, 5 periods; Tissot apparatus, 3 

 periods; preliminary period, 1 hour 2 minutes; first two periods, spirometer 

 unit; apparatus alternated thereafter. Glass nosepieces tested with soapsuds 

 for periods with Tissot apparatus. Pulse-rate varied in range in individual 

 periods from 3 to 9 beats per minute. Respiration-rate remarkably uniform 

 in all periods. Average barometric pressure, 755.7 mm. ; average temperature 

 of air in apparatus, 27.2 C. 



K. H. A., June 7, 1912. Tissot apparatus, 4 periods; spirometer unit, 4 

 periods; preliminary period, 49 minutes; apparatus alternated. Glass nose- 

 pieces tested with soapsuds for each period with Tissot apparatus and found 

 without leak. Subject drowsy at times. Pulse-rate uniform. Respiration- 

 rate very uniform, but depth of respiration varied somewhat. Average baro- 

 metric pressure, 758.2 mm.; average temperature of air in apparatus, 21.7 C. 



P. F. J., June 5, 1912. Spirometer unit, 5 periods; Tissot apparatus, 



2 periods; first three periods with spirometer unit, apparatus alternating 

 thereafter. Glass nosepieces for Tissot apparatus tested with soapsuds. 

 Respiration-rate in third and last periods of experiment (with spirometer unit) 

 somewhat irregular toward end of periods, probably due to drowsiness of sub- 

 ject. Average barometric pressure, 758.8 mm.; average temperature of air 

 in apparatus, 24.5 C. 



P. F. J., June 8, 1912. Tissot apparatus, 3 periods; spirometer unit, 4 

 periods; periods with each apparatus in series. Range in pulse-rate approxi- 

 mately 4 beats per minute in the individual periods. Respiration with 

 spirometer unit in first two periods regular; in third period very rapid and 

 shallow; in fourth period regular. Respiration with Tissot apparatus regular 

 throughout all periods. Average barometric pressure, 764.6 mm.; average 

 temperature of air in apparatus, 20.8 C. 



J. B. T., June 10, 1912. Spirometer unit, 4 periods; Tissot apparatus, 



3 periods; first two periods with spirometer unit, apparatus alternating there- 

 after. Respiration-rate in all periods regular. Average barometric pressure, 

 765.2 mm. ; average temperature of air in apparatus, 20.2 C. 



J. B. T., June 12, 1912. Tissot apparatus, 3 periods; spirometer unit, 4 

 periods; periods with each apparatus in series. Tests made with soapsuds 

 before each period for leaks around nosepieces. Both pulse-rate and respira- 

 tion-rate regular in all periods. Average barometric pressure, 754.8 mm.; 

 average temperature of air in apparatus, 24.1 C. 



J. B. T., June 21, 1912. Spirometer unit, 4 periods; Tissot apparatus, 3 

 periods; preliminary period, 39 minutes; first two periods with spirometer 

 unit, apparatus alternating thereafter. Pulse-rate uniform, except in last 

 period of experiment (with Tissot apparatus) when there was a range of 5 



4 periods; periods with each apparatus in series. Pneumatic nosepieces with 

 both apparatus. Pulse-rate in first period with Tissot apparatus irregular; 

 in other periods fairly regular, range being approximately 3 to 4 beats per 

 minute. Respiration regular in rate, but somewhat irregular in depth in all 



