The postmaster then makes out his “registered letter bill” and “return registered letter bill” each of which contains a full description of the letter consisting of address and number. The registered letter bill is then placed in the package envelope with the letter. The package is then sealed up and the name of the post office for which it is destined, and the number and stamp of the mailing office are plainly marked upon the package. It is then ready for delivery to the route agent or postal clerk upon whose route it properly belongs, who is required to give a receipt for it, and also to keep a complete record of it, as are all officers of the Department who handle registered matter in transit. He must also take a receipt from the officer to whom he next delivers the package. The return registered letter bill is sent in an ordinary envelope in the regular mail to the office of final destination, which will, by reason of the fact that no registered letters are sent in through mails, and only in charge of postal clerks upon day trains, nearly always reach the office in advance of the registered letter; and the postmaster, then knowing that such letter is on the way, is on the lookout for it, and if it comes in due time signs the receipt and returns it to the mailing office. All this is done for a fee of only eight cents in addition to the regular postage. If a registered letter should not reach its destination in a reasonable length of time after the receipt of the return bill, the post master will notify the post master at the mailing office of the non-receipt of the letter. It then becomes the duty of the last mentioned officer to inform a special agent of the fact, who will make out what is called a “tracer,” which is a complete description of the letter, with blank space for each person who handled the original letter to state, from his records and receipts, exactly what disposition he made of it and whose receipt he holds; he then passes it along to the next. Thus by this complete chain of records and receipts, though it may reach from the Atlantic to the Pacific, a registered letter may be readily traced to its final destination, or until the records cease. If a break should occur in the chain and the loss be fastened upon any post office or mail agent, the case is rigidly “investigated” by the proper officer, and if it appears that the loss occurs through carelessness, the loser is made to pay the value of the lost letter, and receive a severe reprimand, and if it should occur again is very apt to be dismissed the service. If the special detective is convinced that the missing letter is stolen, he then takes a different course and commences his system of “decoys,” etc., to catch the thief, and is almost always successful, as the man who robs the mails always becomes careless, and grows bolder with each repetition of the offense.