114 METABOLISM AND GROWTH FROM BIRTH TO PUBERTY. 



per kilogram of body-weight, and to a unit of surface, i. e., the calories 

 per square meter of body-surface. These have both been charted, 

 the former showing a distinct tendency for a downward trend from 

 61 calories at 5 months to an approximate level at 38 calories between 

 the twenty-fourth and forty-first months. It thus appears that per 

 kilogram of body-weight the heat production of the infant is consid- 

 erably greater than that of a child from 2 to 3 years of age. 



370 



310 



PULSE 

 100 



Mos.3 6 



12 15 18 21 24 27 30 33 36 39 42 



FIG. 15. Body-weight, pulse-rate, and basal heat production per 24 hours (No. 145). 



When the calories per square meter are charted (and it must be 

 recalled that we have on this chart only values representing the 

 minimum metabolism at the different ages) we find variations ranging 

 from 1,086 to 841 calories. Although the curve is extremely irregular, 

 there is a tendency downwards, with a slight rebound after 24 months. 

 As this curve stands, it is apparently not so regular as that for the 

 calories per kilogram of body-weight, and taken by itself gives very 

 little evidence of a physiological law correlating the energy output and 

 the body-surface of the child. It should, furthermore, be recalled 

 that (in the case of this child, at least) the body-surface was not 





