The cities which were reported to have turned out the greatest number were New York, Chicago, Boston, Philadelphia, Pittsburg, Buffalo, Detroit, Cleveland, Cincinnati, St. Louis, and San Francisco. Chicago was given the palm for being, at the present moment, the main stronghold of habitual criminals. Nearly every photograph I saw of a young offender was said to represent one of Chicago's hopefuls, and the pictures of the old men were generally described as the likenesses of New York City "talent." Chicago's lead in the number of "professionals" was explained by one man on the ground that it is a Mecca and Medina "for young fellows who have got into some scrape in the East. They go to Chicago, get in with the push, and then start out on the road. The older men train them." A question that I was continually putting to myself when meeting the "professional" was: What made him choose such a career? He is intelligent, agreeable to talk to, pleasant as a travelling companion, and among his kind a fairly good fellow, and why did he not put these abilities and talents to a better use? To understand him well I believe that one must make his acquaintance while he is still living at home, as a boy, in some city "slum." He does not always come from a slum, but, as a rule, this is where he begins his criminal career. In every quarter of this character there is a criminal atmosphere. The criminologists have not given this fact sufficient prominence in their writings. They make some mention of it, but it is seldom given its true significance in their books. The best-born lad in the world can go wrong if forced to live in this corrupt environment. Not that he is necessarily taught to commit crimes, or urged to, although this sometimes happens; they become spontaneous actions on his part. The very air he breathes frequently incites him to criminal deeds, and practice makes him skilful and expert. In another environment, in nine cases out of ten, he could be trained to take an interest in upright living; in this one he follows the lines of least resistance, and becomes a thief. Let me describe the childhood of a criminal boy who will serve as a type for thousands.