viii Preface 



This involves a study of the various problems 

 of children as individuals as well as in their 

 social relationships. 



Good development is the resultant of many 

 forces, among which may be noted heredity, 

 prenatal care of the expectant mother, proper 

 oversight of infants and growing children, 

 food, clothing, housing, education, hours and 

 conditions of study, recreation, expert medical 

 attendance during illness, and the general hab- 

 its of the individual. 



In the frontispiece is shown a statue repre- 

 senting the physical perfection of form in 

 youth. The sculptor is Professor E. Tait 

 McKensie of the University of Pennsylvania, 

 and the figure stands in the American Museum 

 of Natural History. In proportions it repre- 

 sents an average of the fifty strongest men at 

 Harvard as measured by Dr. Dudley A. Sar- 

 gent. I am indebted to Professor McKensie 

 for photographing the figure for me and per- 

 mitting its use in this book. 



Heney Dwight Chapin. 

 June, 1922 



