In this connection it is worth noticing that the best detective agencies train their own operators, selecting them from picked material. The candidate must as rule be between twenty and thirty-five years of age, sound of body, and reasonably intelligent. He gets pretty good wages from the start. From the comparatively easy work of watching or "locating," he is advanced through the more difficult varieties of "shadowing" and "trailing," until eventually he may develop into a first-class man who will be set to unravel a murder mystery or to "rope" a professional criminal. But with years of training the best material makes few real detectives, and the real detective remains in fact the man who sits at the mahogany desk in the central office and presses the row of mother of pearl buttons in front of him. If you know the heads or superintendents of the large agencies you will find that the "star" cases, of which they like to talk, are, for the most part, the pursuit and capture of forgers and murderers. The former, as a rule, are "spotted" and "trailed" to their haunts, and when sufficient evidence has been obtained the police are notified, and a raid takes place, or the arrest is made, by the State authorities. In the case of a murderer, in a majority of cases, his capture is the result of skilful "roping" by an astute detective who manages to get into his confidence. For example, a murder is committed by an Italian miner. Let us suppose he has killed his "boss," or even the superintendent or owner. He disappears. As the reader known, the Italians are so secretive that it is next to impossible to secure any information--even from the relatives of the murdered man. The first thing is to locate the assassin. An Italian detective is sent into the mine as a laborer. Months may elapse before he gets on familiar or intimate terms with his fellows. All the time he is listening and watching. Presently he hears something that indicates that the murderer is communicating with one of his old friends either directly or through third parties. It is then generally only a question of time before his whereabouts are ascertained. Once he is "located" the same method is followed in securing additional evidence or material in the nature of a confession or admission tending to establish guilt. Having previously "roped" the murderer's friends, the detective now proceeds to the more difficult task of "roping" the murderer himself. Of course, the life of a detective in a Pennsylvania coal mine would be valueless if his identity were discovered, and yet the most daring pieces of detective work are constantly being performed under these and similar conditions. Where the criminal is not known, the task becomes far more difficult and at times exceedingly dangerous.