FIG. 298.—STORAGE ROOM OF ICE PLANT.
An ice plant, employing what is known as the “can” system and capable of producing 100 tons of ice in twenty-four hours, requires a building about 100 feet wide and 150 feet long, on account of the great floor space needed to accommodate the freezing tank, and the great number of cans which are immersed in the same. A radical departure from this style of plant is presented in the Holden ice machine. This does not require a multitude of cans and a great floor space, but a lot 25 by 50 feet is sufficient, for the ice is turned out in a continuous process like bricks from a brick machine. The machine works on the ammonia absorption principle, but the freezing is done on the outer periphery of a revolving cylinder, from which the film of ice is scraped off automatically and the ice slush carried away by a spiral conveyor to one of two press molds, in which a heavy pressure solidifies the ice into blocks, which are successively shot down from the presses on a chute to the storage room, as seen in [Fig. 299].
FIG. 299.—HOLDEN ICE MACHINE.
The foregoing examples of ice machines give no idea of the great activity in this field of refrigeration in the Nineteenth Century. Over 600 United States patents have been granted for ice machines alone, to say nothing of refrigerating buildings, refrigerator cars, domestic refrigerators, and ice cream freezers, etc. Among the earlier workers in ice machines, in addition to those already named, may be mentioned the names of Gorrie, patent No. 8,080, May 6, 1851, followed by Twining, 1853-1862; Mignon and Rouart, in 1865; Lowe, in 1867; Somes, in 1867-1868; Windhausen, in 1870; Rankin, in 1876-1877, and many others.
An application of the ice machine which attracted much attention and attained great popularity for a while was that made in the production of artificial skating rinks, in which a floor of ice was frozen by means of a system of submerged pipes, through which the cold liquid from the ice machine was made to circulate. The earliest artificial skating rink is to be found in the British patent to Newton, No. 236, of 1870, but it was Gamgee, in 1875 and 1876, who devised practical means for carrying it out and brought it into public use. His inventions are described in his British patents No. 4,412, of 1875, and No. 4,176, of 1876, and United States patent. No. 196,653, October 30, 1877, and others in 1878.
The Windhausen machine was one of the earliest applications for cooling and ventilating ships. This machine operated upon the principle of alternately compressing and expanding air, and is described in United States patents No. 101,198, March 22, 1870 (re-issue No. 4,603, October 17, 1871), and No. 111,292, January 24, 1871. To-day every ocean liner is equipped with its own cold storage and ice-making plant, refrigerator cars transport vast cargoes of meats, fish, etc., across the continent, and bring the ripe fruits of California to the Eastern coast; every market house has its cold storage compartments, and to the brewery the refrigerating plant is one of its fundamental and important requisites.
The great value of refrigerating appliances is to be found in the retardation of chemical decomposition or arrest of decay, and as this has relation chiefly to preserving the food stuffs of the world, its value can be easily understood. This branch of industry has grown up entirely in the Nineteenth Century, and the activity in this field is attested by the 4,000 United States patents in this class.