

ALIMENTATION AND THE EXPENDITURE 155 



The static expenditure is very much lower during the repose 

 of the night, at the time when the temperature of the body is 

 a minimum. It is only 1,488 Calories per twenty- four hours, 

 and includes also the value of the radiation and convection from 

 the body when the temperature of the surrounding atmosphere 

 is 20 C. ; but this is very small for a man clothed in a fine cotton 

 garment (Atwater) and covered by the sheets of the bed. It is 

 not negligible, however. Let it be called x (see 176). The 

 expenditure (1488 x) is that of an adult absolutely at rest, 

 the work performed by the body being strictly restricted to the 

 internal operation of the organs of life (respiration, circulation, 

 digestion). This is the minimum physiological expenditure. 

 For example, an adult in repose, when the surrounding atmos- 

 phere is at 37 C. would expend (1,488 .r) calories in 24 hours. 



105. (ii). The following table gives an analysis of the gross 

 dynamic expenditure (static + dynamic) for the same subject 

 as befoie. The work done in a period of eight hours being equiva- 

 lent to 603-8 Cal. The work was done on the experimental 

 bicycle. The principle of this instrument is that the back wheel 

 drives a dynamo, the current generated being converted into heat 

 in a suitable resistance (see also 39). This amount of heat is 

 added to the heat radiated by the human body in the calori- 

 meter, ( x ) and the gross dynamic expenditure can be measured 

 with the following results : 



(!) The wheel had a diameter of 0'405 m. (Bulletin, No. 208, p. 12, 1909), 

 that is, a circumference of 1*27 m. ; at each stroke of the pedal the effort 



