I O ]\I U M F(JRD, Physique of Manchester Graviiuay School Boys. 



they occur in the lower classes of society. It is also 

 certain that the intensit}' of their onset is affected by 

 social conditions, so that they are more fatal when they 

 occur in the slums than when they occur in more sanitary 

 homes. It follows that the relation of incidence to 

 mortality is smaller in the lower strata of society than in 

 the higher, though the sequela may be more severe. 



The mortality per thousand from these illnesses for a 

 number of years is given in the Report of the Medical 

 Officer of Health for Manchester for 1910, p. 181. 



In order to compare the age incidence in two different 

 classes of .society, I have analysed the records of a number 

 of children attending the Northern Hospital, Manchester, 

 and compared them with the record cards of the last 

 batch of boys entering the Manchester Grammar .School. 



The following are the results in percentages : — 



