Page:Popular Science Monthly Volume 90.djvu/92

 Safeguarding- the Nation's Money

The Bureau of Engraving maintains a small arsenal, con- stant vigilance and the finest signaling system in the world

��THE Bureau of Engraving and Print- ing, at Washington, D. C., where all paper money, postage and revenue stamps and valuable documents are printed, is one of the most carefully guarded build- ings in the world. It is protected by some of the most modern electrical burglar- alarms, and sixty armed night watchmen patrol the plant.

Five different sig- naling systems are installed in the build- ing, including the watchman's time re- corder, the electric clock system, the di- vision report system, fire alarm system, and the messenger call system.

Not only are watch- men on duty at night, but during every hour of the day as \\^ell. The vaults are said to be among the finest in the world. There are four major vaults, all built alike, and a num- ber of smaller ones. These vaults are guarded by a special force of men, headed by the custodian of the vault. No one is al- lowed near the vaults unless on official bus- by special

���By an elaborate system of mirrors the in- terior of the vaults as well as the surround- ing passages are kept under constant watch

��mess or

permission of the Director of the Bureau. The vaults themselves, separated from the building, are really vaults within vaults. At night, when the doors are closed, two watchmen go completely around them every fifteen minutes. By an elaborate series of mirrors, a watchman can, in walking over the grating, see entirely under as well as on top of each vault; and if he stands at a certain given point he can see all around the vault as well. The vaults themselves are forty by eighty feet, and some twenty feet high. They are built of concrete, about four feet thick, and are reinforced with steel railroad-ties. The concrete is intermeshed

��with burglar wires, so that a knife blade cannot penetrate at any place in the entire structure without sounding an automatic alarm in the office of the captain of the watch. The door itself weighs twenty-five tons, yet it is so perfectly balanced that it can be easily closed with one finger. Because of the great size of this building and the nature of the work carried on, it is imperative that a most complete system be ihstalled to allow the captain of the watch, who is in charge of all the watchmen, to know at all times j ust where each watch- man is and also to be able to communicate with him in case of emergency. In the regular operation of the system the watch- man turns in a sig- nal from each station every five minutes during the night. This signal is received in the office of the cap- tain of the watch in three ways: by the ringing of a bell, by the falling of an an- nunciator drop and by the perforation of a watch-clock dial. Should the watchman fail to ring in on schedule time from any station, the captain of the watch can im- mediately start an investigation.

The system is so laid out that it is impossible for a watchman to ring in on any but the right station at the right time without being detected. Each station is so arranged, that, should the watchman wish to communicate with the captain he can telephone in. On the other hand, when the captain wants one of the watchmen, he shifts a lever, whereupon a horn blows, each man having a certain signal. By means of code signaling this system gives the general alarm to all the watchmen at night.

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