Some men operate on the "single-handed" basis; they travel alone, arrange their own "frame-ups" (personally corner their victims), and keep all the profits. There are a few well-known successful pickpockets of this order, and they are rated high among their fellows, but the more general custom is for what is called a "mob" of men to travel together, one known as the "tool" doing the actual picking, and the others attending to the "stalling." A stall is the confederate of the pickpocket, who bumps up against people, or arranges them in such a way that the pickpocket can get at their pockets. Practically any one who will take a short course of instruction can learn how to stall, but there are naturally some who are more expert than others. A tool who hires his stalls and makes no division of spoils with them will sometimes have to pay as much as $5 a day for skilled men. When he divides what he gets, each man in the mob may get an equal share or not, according to a prearranged agreement, but the tool is the man who does the most work. Of first-class tools, men who are known to be successful, there are probably not more than 1,500 in the United States. Practically every professional offender has a "go" at pocket-picking some time in his career, but there are comparatively few who make a success of it as actual pickpockets; the stalls are numberless. Among the 1,500 there are some women and a fair portion of young boys, but the majority are men anywhere from twenty to sixty years old. The total number of the successful and unsuccessful is thirty, forty, or fifty thousand, as one likes. All that is actually known is that there is an army of them, and one can only make guesses as to their real strength. It is an interesting sight to see a mob of pickpockets at work. It equals football in exercise and tactics, and fencing in cunning and quickness. At the railroad station one of the favourite methods is for the mob to mix with the crowd, pushing and tugging on and near the steps of the coaches. It was my duty to watch carefully on all such occasions, and I was finally rewarded by seeing some pickpockets at work. We were three officers strong at the time, and we had concentrated at the middle of the train, where the pushing was worst. One of the officers was a man who has made a lifelong study of grafts and grafters. He and I were standing close together in the crowd, and suddenly I saw him dart like a flash toward the steps of one of the cars. I closed in also, as best I could, and there on the steps were two big stalls blocking the way, one of them saying to the people in front of him: "Excuse me, but I have left my valise in this car." His confederate was near by, also pushing. Between the two was the tool and his victim, and my companion had slipped in among them just in time to shove his arm in between the tool's arm and the victim's pocket, and the "leather" was saved.