366 



GROWTH 



TABLE LXXL 



From these results we see that the agreement between observed 

 and calculated results is excellent in all cases where a sufficiently 

 large number of subjects have been weighed, except at age 15J, 

 where weight increases more rapidly than theory demands. 



A simple but empirical formula for obtaining " expected " 



A 

 weight is , where A =conceptional age in years and m is a 



constant for each age (see Table LXXII. for values of m and for 

 results). 



(b) Length. It was at first believed that the length curve was 

 of parabolic form of the equation y 2 =a(cc+b), but later and more 

 complete investigation has shown that this is untenable. There 

 is for each type of body a definite relationship between length and 

 weight, viz. : Z= ^mw, where / = length in metres, w = weight in 

 kilograms, and m is a constant for each age (and each type). As 



A 3 I~^T 



(Pfaundler.) 



4 -75m' 



therefore A = 4-75/ 3 or 



4-75 



Pfaundler gives the following examples : 



(i) A boy aged 1 year has a conceptional age <4 = 



Hence length = A/ - = \/0'36 = 0-72 metre, which compares favourably 

 with the value given in Table LXXII. 

 (ii) A boy aged 8 yrs. has A = 8-75. 



3 I'o rjf: 



Hence length= A/J^ = Vl-74 = 1-23 metres. 

 (Average length of boy of 8 yrs. = 1-20 metres.) 



