I devote a special chapter to their class, because I believe that they are the least understood of all offenders, and also, as I stated in the last chapter, because I consider them the real crux of the problem of crime in this country. The petty offender is comparatively easy to discourage, the backwoods criminal will disappear as our country develops, the born criminal, the man who says that he cannot help committing crimes, can be shut up indefinitely, but the professional criminal, thanks to his own cleverness and the league he and the unknown thief have entered into, baffles both the criminologist and the penologist, and he probably does more financial harm to the country than all the other offenders put together. He is the man that we must apprehend and punish before crime in the United States will fail to be attractive, and at the present moment it is its attractiveness which helps to make our criminal statistics so alarming. I have placed him fourth in numerical strength in my general classification, and I believe this to be a correct estimate of the number of those who really make their living by professional thieving. If those are to be included who would like to succeed as professional thieves and fail, and drop down sooner or later into the occasional criminal's class, or into the tramp's class, the position I have given the so-called successful "professional" would have to be changed; but it has seemed best to confine the class to those who are rated successful, and on this basis I doubt whether an actual census taking, if it were possible, would prove them to be more numerous than I have indicated. Seeing and hearing so much of them on my travels, I made every effort to secure trustworthy statistics in regard to their number, and as the majority of them are known to the police, it seemed reasonable to suppose that, if I passed around enough among different police organisations, I ought to get satisfactory figures, but the fact of the matter is that the police themselves can only make guesses concerning the general situation, and I am unable to do any better. When putting queries concerning the number of the offenders in question, my informants wanted me to differentiate and ask them about particular kinds of professionals before they would reply. One very well informed detective, for instance, said: "Do you mean the whole push, or just the A Number One guns? If you mean the push, why you're safe in saying that there are 100,000 in the whole country, but the most of 'em are a pretty poor lot. If you mean the really good people, 10,000 will take 'em all in."