. The elements of materia medica and therapeutics (Volume 2) . he wax is allowed to cool in moulds. Properties of Yellow Bees-wax.—Yellow wax (cera flava) has a re-markable and peculiar odour; its colour is more or less yellow, but varying indegree ; its specific gravity varies from 0-960 to 0-965. It is said to be some-times adulterated with suet, which gives it a fatty feel and disagreeable may be recognised by its solubility in cold alcohol ; bean or pea meal, byits insolubility in oil of turpentine. Wax Bleaching.—This is effected by melting yellow wax (either in a cop-per vess
. The elements of materia medica and therapeutics (Volume 2) . he wax is allowed to cool in moulds. Properties of Yellow Bees-wax.—Yellow wax (cera flava) has a re-markable and peculiar odour; its colour is more or less yellow, but varying indegree ; its specific gravity varies from 0-960 to 0-965. It is said to be some-times adulterated with suet, which gives it a fatty feel and disagreeable may be recognised by its solubility in cold alcohol ; bean or pea meal, byits insolubility in oil of turpentine. Wax Bleaching.—This is effected by melting yellow wax (either in a cop-per vessel, or in a large vat or tub, by means of steam), running it off, while inthe melted state, into a trough, called a cradle, perforated at the bottom withholes, and placed over a large water tank, at one end of which is a revolvingcylinder, almost wholly immersed in water. By this means the wax is solidi-fied converted into a kind of riband, and conveyed on the surface of the waterto the other end of the tank. These ribands of wax are here lifted out, and. On their mathematical form. con8ult Waterhoure. in the Pinny Cyclop art. Bee; and Lord BroughamsDiMrt on Subjects of Science connected with Natural Theology, vol. i. p. 218,1839. 67* 798 ELEMENTS OF MATERIA MEOICA. conveyed in baskets to the bleaching grounds, where they are exposed to the airfor one or two weeks (according to the state of the weather), being turned everyday, and watered from time to time. The wax is then re-melted, re-ribanded,and re-bleached; it is subsequently refined by melting in water acidulated withsulphuric acid. Properties of White Wax.—White Wax (cera alba; cera dealbata) is yel-lowish-white; I have never met with pure wax perfectly white. The circularcakes of commerce, as well as wax candles, always contain spermaceti, whichthe dealers add to improve the colour. Pure wax is solid, brittle, inodorous, ornearly so, insipid, fusible, and at a much higher temperature decomposable. Itsspecific grav
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