There is no actual "murder commission," as there is in some foreign countries, but every person and device likely to be of assistance is quickly concentrated on the spot. Not a second of time is lost from the moment the crime is discovered. First on the spot are the divisional detective-inspector and his staff. Telephones and the chattering tape machines tell the details in ten score of police stations. Mr. Basil Thompson, the Assistant-Commissioner, and Mr. McCarthy will probably motor in haste to the spot. Specialists are summoned from all quarters. Not a thing is moved until a minute inspection has been made, plans drawn, photographs taken, notes made, and finger-prints sought for. It may be necessary to get certain points settled by experts, by Dr. Wilcox, the Home Office analyst, Dr. Spilsbury, the pathologist, by a gunsmith, an expert in handwriting, or any one of a dozen others. The very best professional assistance is always sought. The danger of amateur experts was exemplified some years ago, when a woman who committed suicide tried to destroy every mark of identity on her clothes. She missed one detail--a laundry mark worked in red thread on her dressing jacket. The mark was read as E.U.X.A.O.Z., and these letters were advertised far and wide. Then the President of the Laundry Association examined the garment, and conclusively showed that the marks really represented E.48992. It was, he declared, not a laundry mark at all, but a dyers and cleaners' mark. And this was what it proved to be. While the experts are busy the divisional inspector and his men are no less so. They are making a kind of gigantic snowball enquiry, working backwards from the persons immediately available. A. has little to say himself, but there are B. and C. who, he knows, were connected with the murdered person. And B. and C. having been questioned speak of D. E. F. and G.; and it may be that a score or more persons have been interviewed ere one is found who can supply some vital fact. I have known a murder investigation held up a couple of hours while search was being made for someone to supply the address of some other person who _might_ know something. All very tedious this, and very different from the methods of the detectives we read about. But then the detectives of fiction somehow avoid the chance of the flaws in their deductions being sought out by astute cross-examining counsel. If a description of the suspected murderer is available a telegraphist working at Scotland Yard will get it, with the letters "A.S." (all stations) attached. As he taps his instrument the message is automatically ticked out simultaneously at every station in the metropolis.