Cera Flava and Alba. Yellow Wax and White Wax.
Wax, commonly known as Beeswax, is a peculiar secretion of the honey bee, being the substance of which the honey-comb is chiefly composed. The wax that is procured from vegetables is not here alluded to.
Yellow Wax is obtained by slicing up the honey-comb, straining and expressing from it the honey, and then melting the debris in boiling water. After some hours boiling, with occasional stirring, the wax becomes well separated from the impurities, which either settle to the bottom of the vessel, or are dissolved by the water, while the wax itself rises to the surface, and becomes hard on cooling. It is still further purified by a second boiling, and then strained into flat pans. It always retains some peculiar principles, which give it its characteristic yellow color, as well as its taste and smell. It is hard; will break with a granular fracture, but cuts with a smooth surface; softens at a moderate heat, and melts at 142 deg. F. It is a very little lighter than cold water. It is many times adulterated with resin, which gives it a smooth instead of a granular fracture. Cold alcohol will dissolve out the resin, and leave the wax minutely honey-combed. Meal and earthy adulterations may be separated by boiling water.
White Wax is prepared from the yellow wax by various processes of bleaching. The most common method is that of pouring the melted wax in small streams upon a revolving cylinder, where it cools in very thin layers. These are spread in the sun upon linen stretchers, and sprinkled frequently with water. A second, or even a third melting, is necessary to discharge all the yellow color. The total process requires two or three weeks. M. Cassgrand, of France, has patented a method of bleaching it by steam. He melts it by steam, passes it through a coil along with steam, pumps it into a steam-heated pan, where it is washed with hot water, then granulated with cold water, and afterwards exposed to the air and light in very thin cakes. White wax is without taste or smell, harder and less unctuous than the yellow, with a melting point of 140 deg. F ., but retaining its fluidity (when once melted) till it reaches a temperature of about 135 deg. F. Its specific gravity is about the same as the yellow wax. It may be partly decomposed and volatilized at a high heat, and its vapor will burn with a pure bright flame. Resin easily unites with it when the two are melted together; the fixed and volatile oils dissolve it readily, soda and potassa solutions form soapy compounds with it, boiling alcohol and ether dissolve it very sparingly, and deposit it on cooling. It is sometimes adulterated with white lead, which will fall to the bottom on melting; with tallow suet, and other fats, which may be detected by their quickly turning lime-water milky.
Pharmaceutical Preparations: I. Simple Cerate, Spermaceti Cerate. White wax, three ounces; spermaceti, one ounce; olive oil, six fluid ounces. Melt together the wax and spermaceti; heat the oil and add to the others, and stir the whole till cool. This is a fine protecting cerate for all simple dressings. It is also used as a vehicle for more active preparations, and especially for making medicated cerates by incorporating with it any -solid extract, previously softened with alcohol.
II. Simple Ointment. White wax, one pound; lard, four pounds; melt together with a moderate heat, and stir till cold. This is a softer preparation than the above, and rather more serviceable in cold weather. It is used for the same general purposes as the cerate.
The Physiomedical Dispensatory, 1869, was written by William Cook, M.D.
It was scanned by Paul Bergner at http://medherb.com