The majority of persons realize that it pays to register their money and insure their packages because, once this precaution has been attended to, the government exercises special care in the handling of these and makes it extremely difficult for crooks to get anywhere near them. If a registered letter disappears there is a clean-cut trail of signed receipts to follow and somebody has to bear the burden of the loss. But even with these precautions, the Registered Section is looted every now and then. One of the biggest cases of this kind on record was that which occurred in Columbus when letters with an aggregate value of one hundred thousand dollars just vanished into thin air. Of course, they didn't all disappear at one time, but that made it all the more mysterious--because the thefts were spread out over a period of some five or six weeks and they went on, just as regularly as clockwork, in spite of the precautions to the contrary. The first of the losses, as I recall it, was a shipment of ten thousand dollars in large bills sent by a Chicago bank to a financial concern in Columbus. When working on that single case, of course, the officials of the department were more or less in the dark as to the precise place that the disappearance had taken place, in spite of the fact that there were the usual signed slips indicating that the package had been received at the Columbus Post Office. But clerks who are in a hurry sometimes sign receipts without being any too careful to check up the letters or packages to which they refer--a highly reprehensible practice, but one which is the outgrowth of the shortage of help. It was quite within the bounds of possibility, for example, for the package to have been abstracted from the Chicago office without the loss being discovered until Columbus checked up on the mail which was due there. But a week or ten days later came the second of the mysterious disappearances--another envelope containing bills of large denomination, this time en route from Pittsburgh to Columbus. When a third loss occurred the following fortnight, the headquarters of the Postal Inspection Service in Washington became distinctly excited and every man who could be spared was turned loose in an effort to solve the problem. Orders were given to shadow all the employees who had access to the registered mail with a view to discovering whether they had made any change in their personal habits, whether they had displayed an unusual amount of money within the past month, or whether their family had shown signs of exceptional prosperity. It was while the chief was waiting for these reports that Elmer Allison blew into Washington unexpectedly and strolled into the room in the big gray-stone tower of what was then the Post-office Department Building, with the news that he had solved the "poison-pen case" in Kansas City and was ready to tackle something else.