24 



METABOLISM DURING WALKING. 



B 



FIG. 3. Respiration counter. 



A, spirometer frame; B, cord from spirom- 

 eter-bell leading to counterpoise; C, 

 fiber sleeve; D, D\, mercury cups; E, 

 E\, platinum-pointed fork for com- 

 pleting the circuit through D and 

 DI; F, stop; G, leads to electrically 

 operated counter shown in fig. 4. 



Ventilation recorder. The total volume of air drawn into the lungs 

 was registered by means of an attachment previously described, 1 and 

 commonly referred to as the "ventilation adder." This consists of an 

 aluminum wheel (w, fig. 1) 

 attached to the apparatus in 

 such a manner that each down- 

 ward movement of the spirom- 

 eter-bell due to inhalation 

 by the subject moves the 

 wheel upward. By means of a 

 signal magnet, each revolution 

 of the wheel is recorded upon 

 the kymograph. From this 

 graphic record and the volume 

 corresponding to a revolution 

 of the wheel, the total inspira- 



tory Ventilation Can be CalcU- FlG - 4. Electrical counter for recording number of 

 I j ~ , i respirations. For operating device and con- 



lated. At first the pulmonary nections with the apparatus, see fig. 3. 



ventilation during grade walk- 

 ing was found by actual measurement of the pen tracings on the kymo- 

 graph, but later with the ventilation adder. The ventilation data 

 secured have been reduced to standard conditions for temperature and 

 pressure for recording in the tables. 



Mouthpiece. The mouthpiece used was of the Denayrouse type. 2 

 At the beginning of the study strips of surgeon's plaster across the lips 



'Benedict, Deutsch. Archiv f. klin. Med., 1912, 107, p. 176; see also Carpenter, Carnegie Inst. 

 Wash. Pub. No. 216, 1915, p. 40. 



2 P. Regnard, Recherches experimentales sur les variations pathologiques des combustions 

 respiratorires, Paris, 1879, p. 286; also Carpenter, Carnegie Inst. Wash. Pub. No. 216, 1915, 

 p. 54. 



