Ill] 



OF BODILY WEIGHT 



69 



during the first two or three years of hfe. After a shght recovery, 

 it runs nearly level during boyhood from about five to twelve 

 years old; it then rapidly rises, in the "growing period"' of the 

 early teens, and slowly and steadily falls from about the age of 

 sixteen onwards. It does not reach the base-line till the man is 

 about seven or eight and twenty, for normal increase of weight 

 continues during the years when the man is "filling out," long 

 after growth in height has ceased ; but at last, somewhere about 

 thirty, the velocity reaches zero, and even falls below it, for then 



S 3 



i4 



year 



Fig. 5. Mean annual increments of weight, in man and woman; 

 from Quetelet's data. 



the man usually begins to lose weight a little. The subsequent 

 slow changes in this acceleration-curve we need not stop to deal 

 with. 



In the same diagram (Fig. 5) I have set forth the acceleration- 

 curves in respect of increment of weight for both man and woman, 

 according to Quetelet. That growth in boyhood and growth in 

 girlhood follow a very different course is a matter of common 

 knowledge ; but if we simply plot the ordinary curve of growth, 

 or velocity-curve, the difference, on the small scale of our diagrams, 



