One cannot here attempt the task of showing what youth is. This is no place for it. The psychology of youth is in its infancy. True, the foundation is being laid by such men as Stanley Hall (in his book Adolescence) and by others. But the study of the adolescent is new. The existence of the elementary school has made it almost necessary to carry on the study of early childhood and to get to know something about the child. But the existence of adult schools, evening classes and technical schools, does not seem to have made it so clear that there is something to learn about youth as well as about childhood. Most people who consider evening schools or training colleges even, do so from the point of view of critics, not students, and so it happens that few are on really safe ground when they are dealing with the hobbledehoy of either sex. A word or two is all we can say here.
The adolescent, or girl or boy between thirteen and twenty-one is living through a period of rapid growth and great physical development. How great and rapid this change is we may judge from the great increase in the weight of the various organs, but more especially of the heart. Between the ages of fourteen and eighteen the child appears indeed to be passing into
