II. Cera Flava, Yellow Wax

II Cera Flava, Yellow Wax. The honeycomb, after draining the honey, is melted in water, impurities allowed to subside, then cooled; a second or third melting produces each time a purer product. It is a yellow, gray-brown solid, agreeable, honey-like odor, faint characteristic taste, somewhat brittle when cold, fracture dull, gran-ular, not crystalline, plastic by heat of hand, soluble in chloroform, ether, fixed or volatile oils, partly in benzene, carbon disnlphide, sparingly in alcohol, when boiling dissolving cerotic acid and part of the myricin; insoluble in water; sp. gr. 0.955, melts at 63° C. (146° F.). Impurities. - Fats, fatty acids, Japan wax, rosin, soap, paraffin, ceresin - this latter most frequently, 10-45 p. c.

Constituents. - Hydrocarbons, C27H56 and C34H64, 12-14 p. c, cerin or cerotic acid, C27H54O2, crystallizes from boiling alcohol; myricin or myricyl palmitate, C30H61C16H31O2 (principal constituent, acicular crystals, soluble in hot ether), an alcohol, C25H52O, ceryl alcohol, C27H56O.

Preparations. - 1. Cera Alba. White Wax. (Syn., Cer. Alb., White Beeswax; Fr. Cire blanche; Ger. Cera alba, Weisses Wachs.)

Manufacture: Yellow wax, in thin sheets, is bleached by exposure to moisture, air, and sunlight. It is a yellowish-white solid, somewhat translucent in thin layers, faint characteristic odor, nearly tasteless, non-rancid; sp. gr. 0.955, melts at 63° C. (146° F.).

Preps.: 1. Ceratum, 30 p. c. 2. Unguentum, 20 p. c. 3. Unguen-tum Aquw Rosas, 12 p. c.

2. Emplastrum Elasticum. Rubber Plaster. (Syn., Emp. Elast., Rubber Adhesive Plaster; Fr. Emplatre Caoutchouc; Ger. Kautschuk-pflaster.)

Manufacture: A mixture of rubber, resins and waxes, with a filler of an absorbent (orris root, starch, etc.), mechanically mixed and spread upon fabric - cotton cloth, etc.

3. Ceratum Cantharidis, 1.75 p. c. 4. Ceratum Resinw, 15 p. c. 5. Emplastrum Resinoe, 6 p. c. 6. Unguentum Picis Liquidoe, 15 p. c.

Properties and Uses. - Mostly as bases for plasters, cerates, ointments; formerly in diarrhoea, dysentery, rheumatism, gleet, neuralgia; locally as a protective from cold and to aid cutaneous transpiration.