190 



COMPARISONS OF RESPIRATORY EXCHANGE. 



M. J. S., July 20, 1912. Mask, 4 periods; glass nosepieces, 3 periods; 

 periods alternating. Both mask and nosepieces tested with soapsuds. Sub- 

 ject preferred mask, as nosepieces made edges of his nostrils sore and with the 

 mask he felt that he had more freedom in breathing. He complained of sore- 

 ness and pain on the left side of body. No pulse records taken. Respiration- 

 rate at beginning of periods uneven, but became more regular by the middle 

 of the period. Average barometric pressure, 765.7 mm. ; average temperature 

 of air in apparatus, 24.4 C. 



M. J. S., July 22, 1912. Subject had midday lunch previous to experiment; 

 experiment began at l h 53 m p. m. Sat in Morris chair instead of lying on 

 couch. Mask, 3 periods; pneumatic nosepieces, 3 periods; periods alternating. 

 Pulse-rate varied in periods with mask and in second period with nosepieces, 

 the range being from 5 to 6 beats per minute; pulse-rate very regular in the 

 other periods with nosepieces. Respiration-rate very regular in all periods. 

 Average barometric pressure, 757.2 mm.; average temperature of air in appa- 

 ratus, 20.9 C. 



L. E. E., November 18, 1912. Mask, 3 periods; pneumatic nosepieces, 

 2 periods; periods with mask and nosepieces in series; preliminary period, 1| 

 hours. Subject thought it would be an advantage to have a weight attached 



T- T- T ~T- nr 



Fia. 50. Types of respiration of subject L. E. E. as recorded from the spirometer bell in the 



second period on November 18, 1912. 



Upper curve, beginning of period. Lower curve, end of period. Time line, minutes. 



Original size. 



