CAS′TORIN. Syn. Castorin′a, Castoreum camphor. When castor is cut into small pieces and boiled in about 6 times its weight of alcohol, crystalline substance (castorin) is deposited by the filtered tincture in cooling. By re-solution in alcohol it may be obtained under the form of colourless, prismatic, acicular crystals.
Obs. Genuine Russian castor, although the most expensive, must be employed in the above process, as scarcely any castorin can be obtained from the American variety.
Prop., &c. Castorin has the odour of castor, and a coppery taste; it is inflammable, and is soluble both in ether and hot alcohol.
CASTS. In preparing casts and moulds with gelatin, wax, fusible metal, and similar substances, it is important to use them at the lowest temperature compatible with fluidity; as when only a few degrees hotter the water which adheres to the things from which the
casts are taken is converted into vapour, and produces bubbles. Fusible metal may be allowed to cool in a teacup until just ready to set at the edges, and then poured into the moulds. In this way beautiful casts from moulds of wood, or of other similar substances, may be procured. When taking impressions from gems, seals, &c., the fused alloy should be placed on paper or pasteboard, and stirred about till it becomes pasty, from incipient cooling, at which moment the gem, die, or seal should be suddenly stamped on it, and a very sharp impression will then be obtained.
CATALEP′SY. Syn. Trance; Catalep′sis, Catalep′sia, L. A disease in which the organs of sense and motion cease to exercise their functions, and the heart and lungs feebly perform their offices, and in a scarcely perceptible manner. The paroxysm generally comes on without previous warning, and its duration varies from a few minutes to several days, and if medical reports are to be credited, sometimes for a much longer period. Dr Cullen seriously affirms that this disease is always counterfeited.
Treat. Ammoniacal stimulants applied to the nostrils, and spirituous liquors injected into the stomach, with general friction of the body, and free access to pure air are the best remedies. Electricity and galvanism should also be had recourse to when the necessary apparatus is at hand.
CAT′APLASMS. See Poultices.
CAT′ARACT. An opaque condition of the lens of the eye. It is a common cause of blindness. It can only be cured by a surgical operation.
CATARRH′. Syn. Catarrh′us, L. The “cold in the head,” or “cold on the chest,” of domestic medicine. Influenza is a severer form of this complaint, and has been called epidemic catarrh.