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Show ICE MADE BY MEANS OF ETHER IT IS WELL KNOWN that ether can be made to vaporize so speedily as to emit intense cold, and if, when covered by water its evaporation be [unreadable] will escape so quickly as to [unreadable] the water to freezing point. Hence ether is often used in preparing freezing? mixture; and a machine has lately been constituted for making ice by means of [unreadable section] circulating pump, and one of ? ice boxes according to the quantity required - a steam engine, supplying the motive power. The two inlet passages of the air pump are connected by a copper pipe, from which branches another copper pipe that places them in communication with the refrigerator, which is a felt-covered vessel of cylindrical shape, the tubes being made of copper and riveted to brass end-plates. The two outward valves on the other side of the air-pump communicate with the other condenser, which is similarly constructed to the refrigerator. The tubes communicate at each end with metal chambers, one of which serves as a receptacle for the air that enters the condenser. The whole is immersed in a wooden tank, through which a stream of water constantly passes for cooling and condensing the ether vapor. A vacuum is maintained by the air-pumps in the refrigerator, vaporizing the other at a low temperature. This operation causes an absorption of heat, which reduces the temperature of the strong brine that is made to circulate through the tubes and ice box. The ice box is a tank of red deal? varnished inside, with partitions with holes in them to allow a slow circulation of the brine. Zinc molds of different widths, according to the shapes of the blocks of ice required, are filled with pure water and suspended between the partitions. |