Page:The museum, (Jackson, Marget Talbot, 1917).djvu/216

186 Journal, XI, 131), no museum which possesses archæological material should be without a copy, as a clearer understanding by the museum staff of the chemical action of the salts to which all antiquities have been exposed would often prevent disintegration of important specimens.

SAFETY DEVICES Electricity is a great help in safeguarding museum collections. In every large city in the United States there is a company which makes it a business to assist in watching property at night. This is done by means of telegraphic communication. Wires run from a centrally located office of this company to each building that it is employed to watch, pass through the walls of the building to boxes so located that the night watchman, in order to get to them, must pass through every room. At stated intervals the watchman makes his rounds and puts his key into each box as he comes to it. This registers at the central office, and if a certain number of minutes go by without the reports, the company sends men to investigate the cause of the delay. In the morning, reports are mailed giving the exact time at which the watchman rang in each box. Special safeguards for the watchman may be arranged by having one box that is not rung in regularly. If