166 METABOLISM AND GROWTH FROM BIRTH TO PUBERTY. 



thereafter there is a tendency for a slow but reasonably regular fall 

 with increasing areas. The scatter of the points about this central 

 line is very wide. If we take tentatively the line corresponding to 

 1,000 calories per square meter as running through approximately 

 the center of the curve, the deviations either side of this line exceed 

 10 per cent in a large number of cases; for the children with the smaller 

 body-surface they exceed plus or minus 25 to 30 per cent. The 

 chart is important, however, in indicating substantially the earlier 

 findings on the body-weight charts, in that with small surface-areas 



Cals. CALORIES PER SQ. M. REFERRED TO SURFACE. GIRLS. 



Fio. 41. Basal heat production of girls per square meter of body-surface per 24 hours 



referred to surface. 



Points inclosed in squares signify puberty established. For No. 239 compare point inclosed in 

 diamond (prepubescence) with point inclosed in square at 1.272 sq. m. (puberty). 



there is a greater intensity of metabolism per unit of surface, not 

 forgetting the intimate relationship between surface and weight, and 

 that this does not depend upon a causal relationship between surface- 

 area and heat-loss. While this chart is not readily compared with 

 other charts on the weight and age bases, it is clear that the scatter 

 of the points is so great as to rule out any conception of a physiological 

 law indicating relationship between the heat production per unit of 

 surface and the actual surface as measured on the child. 



In considering the calories per unit of surface-area referred to total 

 area with girls (fig. 41), the characteristic wide scatter of points noted 

 with boys is likewise here observed. While the line corresponding to 

 1,000 calories would roughly fit into the general middle of the curve, 

 the deviations either side of this point range from to nearly 40 per 

 cent for the children of smaller body-surface but from 0.7 to 1.1 sq. m., 

 the points group themselves somewhat better about the central line 

 than they do with boys. The specific high metabolism with the smaller 

 children and the absence of any regularity in the chart as a whole which 

 would suggest a physiological law should be emphasized. 



