410 THE HUMAN MOTOR 



2841 x 3-6 



100 



A consumption per hour of : 



= 1-023 litres 



.17-53 litres. 

 3-5 



(b) The subject at work, under the following conditions : 

 The subject chose his own attitude and kept it, as far as possible 

 uniform throughout the experiment. The feet were kept in a 

 definite position. Hence, the height of the vice being fixed, the 

 general attitude of the body might be considered as constant. 



The subject (A.C. as before) worked for a period of 3J minutes 

 and made 54 strokes of the file per minute, (The experiment is 

 depicted in fig. 282.) The results were as follows : 



Air expired in 3 J minutes 70 litres 



Respirations per minute , 28 



Temperature 17-5C 



Barometric pressure 758 mm. 



The analysis gave 



C0 2 3-7% 

 2 17-2% 



An absorption of 21 17-2 = 3-8%. 

 The " respiratory quotient " 



CO, _ 3-7 __ 

 ^ 53- 



The volume of gas (reduced to OC and 760 mm. barometric 

 pressure) was 66-455 litres. 



The consumption of oxygen (at OC and 760 mm.) was : 

 66-45 x 3-8 



100 



A consumption per hour of : 

 2-525 X 60 



= 2-525 litres. 



= 43-921 litres. 



3-5 



The corresponding equivalents of the above consumptions, 

 in grand calories, as deduced from the " respiratory quotients " 

 are, per litre. 



The subject at rest, 4-9 Cal. 

 The subject at work, 5-05 Cal. 



Hence the equivalent expenditure per hour in grand calories 

 is: 



At rest 17-53 x 4-9 = 85-91 Calories 



At work 43-29 x 5-05 = 218-62 Calories 



