Robbery and burglary are generally counted as crimes of violence, but they should be properly classed under property crimes. Every motive that leads to getting property in illegal ways applies to these crimes. There is added to the regular causes of property crimes the element of danger and adventure which makes a strong appeal to boys and men. I am inclined to think that few mature men have committed one of these crimes, unless they began criminal careers as boys. Such crimes especially appeal to the activity and love of adventure which inhere in every boy. They are committed for the most part by youths who have had almost no chance to get the needed sport and physical experience incident to boyhood. The foot-ball, base-ball, polo or golf player very seldom becomes a robber or a burglar. Almost no rich man or rich man's son becomes a robber or a burglar. Those who fall under this lure are mainly the denizens of ............