METABOLISM AS AFFECTED BY GROWTH. 



133 



practical as well as physiological interest as indicating that, in an 

 attempt to secure a more nearly perfect measure of normality, the 

 evidence as to the general trend of the metabolism has not been 

 affected. One can thus, even at this point, make the deduction that 

 with the general population as studied, the deviations above or below 

 a central tendency are such as to balance, and that the influence upon 

 metabolism of slight deviations from physical normality is negligible. 



GENERAL TREND OF METABOLISM WITH INCREASING AGE. 



In this series of group charts, the first comparisons have been made 

 for the total metabolism as referred to age. 



TOTAL CALORIES PER 24 HOURS REFERRED TO AGE (BOYS). 



The total calories per 24 hours referred to age for the boys have 

 been charted in figure 22. An inspection of this chart shows a rapid 

 rise in the total metabolism during the first year of life and from the 



FIG. 22. Basal heat production of boys per 24 hours referred to age. 

 Point inclosed in square signifies puberty established. 



first to the thirteenth year a somewhat slower but steady increase. 

 This general trend seems to be continued beyond the thirteenth 

 year; but only three points are available for comparison beyond this 

 age. 



The interpretation of the sketched curve is beset with a number of 

 difficulties. In the first place, the arbitrary laying-down of a smoothed 

 curve on a plot of this character gives too much weight to the possi- 

 bility of a constancy in metabolism. That this constancy is not 

 actually present is clearly shown by the deviations from the line all 



