with wood is now considered perfectly safe provided an asbestos paper covering is used or the wood is treated with a fire-proofing liquid, though the chemical properties of this liquid must be tested, as the acid fumes may prove deleterious to the paintings hung upon the wall.
The director is faced by a double problem in any building where there is danger of fire, for it must be possible to rapidly detach the pictures from the wall and yet the frequent attempts to steal objects from museums and exhibitions make it desirable that everything should be fastened in as rigid a way as possible. In one museum, the picture gallery is on the top floor of a none too fire-proof building. The Trustees of the Museum gave directions that all pictures should be so arranged that they might easily be taken out in case of fire, and then they came one day and playfully took down picture after picture and moved them into another room in the gallery in order to give the poor director a shock and to show him how easily a thief might carry off a full collection. Such cases must be dealt with by the ingenuity of the individual museum director. There are certain devices employed, especially in European museums, to put up small pictures and prints. A screw which requires a patent screw-driver is used. This screw is provided with two small
