Page:The museum, (Jackson, Marget Talbot, 1917).djvu/158

132 operator. One of our American museums has built a vault, just outside the building proper, which is so constructed as to be as airtight as possible. In this the tapestries are sealed for a week at a time, a small saucer of carbon disulphide being placed in the cell with them. This vault was doubtless almost as expensive to construct as the far more efficient device used in the Swedish museums and in Dresden. [See Museumskunde, vol. IV, p. 77, and Museums Journal, vol. IV, p. 205; also Dr. A. B. Meyer, Bericht iiber neue Einrichtungen in Dresden (1903), p. 22.] This consists of a large metal cylinder about four feet across and eight feet long with a door at one end which can be clamped on in such a way as to make the receptacle air-tight. Within the chamber are racks upon which the tapestries or other articles to be disinfected can be laid. A pump supplied with a gauge makes it possible to create a complete vacuum. When this has been obtained the carbon disulphide fumes are introduced and allowed to remain for twenty-four or forty-eight hours according to the condition of the objects to be cured. At the end of this time the carbon disulphide fumes can be pumped out and fresh air admitted until the pressure in the chamber equals that of the room, when the door can be opened and the tapestries