52 THE GROWTH OF THE BRAIN. 



The accompanying Fig. 9 expresses the facts of the 

 table in the form of curves. 



In order to correct the weight for clothing, the obser- 

 vations on the proportional weight of clothing made by 

 Bowditch may be employed. 1 



TABLE 3. WEIGHT OF INDOOR CLOTHING GIVEN IN PER- 

 CENTAGE OF THE BODY-WEIGHT. BOSTON SCHOOL-CHIL- 

 DREN. (Bowditch.} 



If the construction of the chart is understood, it will 

 be seen that the records of increase, both in weight and 

 stature, show that the absolute increase from year to 

 year is not the same ; for were it so, the lines indicating 

 increase would be straight. As a matter of fact, they 

 are sinuous, thus indicating variations in rate. The 

 greater the annual increase, the more nearly the record 

 , approaches the vertical, and the slower it is, the more 

 horizontal becomes the curve. Glancing at the curve for 

 the males, it is seen that for the first year of life increase 

 in weight is rapid. This is followed by a period of 

 slower increase up to seven years of age. From here 

 the weight increases again more rapidly up to sixteen 

 years, with a maximum rate between sixteen and seven- 

 teen years. The rate then falls to twenty-five years, and 

 from that time on, if the curve were continued up to fifty 

 years, the increase would be slight, although continuous. 

 In this later period, from twenty- five years onwards, 

 the accumulation of body-fat is the chief cause of the 



1 Bowditch, The Growth of Children. Report of the State 

 Board of Health of Massachusetts, Boston, 1877. 



