J. A, Harris and F. G. Benedict 277 



The fact that the average metabolism is lower when it is cal- 

 clated from individual minima than when it is computed from 

 ilividual means furnishes no argument in favor of either of 

 te methods of computing the metabolism constant. Conclu- 

 g&amp;gt;ns in regard to this point must be drawn from the results for 

 vighting discussed aboVe, and from a consideration of the varia- 

 lities. 



From Table X we note that in whatever units heat production 

 i expressed, the variation in the population metabolism (meas- 

 i3d in either the absolute terms of the standard deviation or in 

 ts relative terms of the coefficient of variation) is lower when the 

 iiividual means are employed than when individual minima are 

 usd as a basis for calculating the population constants. 



If the securing of a constant with the lowest probable error is 

 ce of the goals to be attained, the method of means is, therefore, 

 t be preferred over the method of minima. 



III. SUMMARY. 



In all special investigations in human calorimetry some stand- 

 al constant measuring the metabolism of the normal individual 

 cist be used as a basis of comparison. The selection of this 

 cistant presents a problem of considerable difficulty from three 

 ales. 



The first is that of the physiological conditions under which the 

 bsal metabolism of the individual shall be measured ; the second 

 isthat of the unit in which the caloric output of the individual 

 sill be expressed ; the third is that of the method by which the 

 svtistical constants for the standard series shall be obtained. 



Basal metabolism measurements are generally made in two or 

 nire periods, with the subject in the postabsorptive state and in 

 cnplete muscular repose, on the same day. Experimental 

 piods which show evidence of muscular activity or of faulty 

 tihnique in the analyses are discarded. So called minimum 

 priods are utilized for obtaining a mean for the day. This may 

 b designated as the daily mean. 



It may be reasonably assumed that the results of the several 

 piods of measurement on a given day stand in the relation of 

 dplicate, triplicate, etc. analyses, and that it is not necessary to 



