150 METABOLISM AND GROWTH FROM BIRTH TO PUBERTY. 



of 7 years that the individual points tend to lie reasonably close to the 

 general smoothed curve. 



From the general picture presented by the chart for girls, it can be 

 seen that the conclusion drawn from that for boys still holds, namely, 

 that the calories per kilogram of body-weight exhibit such wide devia- 

 tions from a general mean as to make it impossible to conceive of 

 anything approximating a physiological law associating the heat 

 production per kilogram of body-weight with the age. The scattering 

 of the points makes the laying-on of this smoothed curve a distinct 

 violation of mathematics and open to severe criticism. We wish 

 again to emphasize that the curves on all of these charts are not to 

 be interpreted on the basis of mathematical accuracy, but simply to 

 indicate the central tendency and general trend. 



CALORIES PER KILOGRAM OF BODY-WEIGHT PER 24 HOURS REFERRED TO AGE (EARLIER 



INVESTIGATORS) . 



Since the measurement of the metabolism per unit of mass plays 

 such an important role with the earlier writers, the comparatively few 

 individual values found by other investigators with boys are plotted 

 in figure 32. On this chart we have likewise laid our general line 



Cals. 



CALORIES PER KILO. REFERRED TO AGE. 



BOYS. 



Yrs. 1 



8 



10 11 12 13 14 15 16. 



FIG. 32. Basal heat production of boys per kilogram of body-weight per 24 hours 



referred to age (earlier investigators). 



from figure 30. With the single exception of one value at the age of 

 2 months, no other point in the entire series lies below our general 

 line up to the age of 13 years, but for the most part they lie very con- 

 siderably above our line. Beyond 13 years two points obtained by 



