4 M\J^iFORD,P//j'su/!(c of MancJiester Gravnnar School Boys. 



Altered relative length of stay in the school of siiiall- 

 sized scholars and larger-sized, pJiysically more rolnist non- 

 scholars during periods of most active gro2vth. One other 

 change in personnel may be that boys of good physique 

 who are not studying for scholarship, but are intended 

 for commercial pursuits, and who are not subject to so 

 much strain in school life, stay a year longer at school. 

 Such boys of particularly good physique would help up 

 the average. That this factor is a considerable one is, I 

 think, indicated by the fact that the improvement in 

 physique is not noticed among the scholars who stay after 

 ly years of age. 



It is probably far more easy to depress bodily growth 

 than to stimulate it ; and it is certain that the most potent 

 external effect on growth is that which is exerted at the 

 very commencement of life. 



Among the stimulants to grozvth must be mentioned 

 climate and fresh air, bodily activity and food. 



1st. Atmospheric conditions -which iiifliioice climate. 

 Meteorological observations in Manchester and Salford 

 go back as far as 1868, when Dr. Tatham was Medical 

 Officer for Salford. Unfortunately these do not include 

 estimation of the amount of sunshine, or the chemical or 

 other analysis for impurities in atmosphere. I have not 

 been able to find in these weather records any appreciable 

 change of mean barometric pressure or mean temperature, 

 but I am informed that the condition of the atmosphere 

 as regards smoke and other impurities is immensely better 

 than it was. Further, although there is no record of the 

 amount of sunshine, yet a purer atmosphere, due to a 

 material diminution in amount of smoke, must impK^ 

 more of the sun rays permeating through it, if not to 

 the extent of actual sunshine, yet sufficient to have 



