BEESWAX 517 



Description. Yellow wax is a yellowish or brownish yellow solid, 

 with an agreeable, honey-like odour, breaking with a granular fracture, 

 and not unctuous to the touch. It is readily and entirely soluble 

 in hot oil of turpentine, partially soluble in alcohol. It is practically 

 insoluble in water and in boiling aqueous solution of sodium hydr- 

 oxide, the two latter liquids after filtration being neither turbid, nor 

 becoming turbid on the addition of hydrochloric acid. 



The specific gravity of wax varies from 0-958 to 0-970 ; melting-point 

 from 61 to 64 ; refractive index at 80 1-4380 to 1-4420. These 

 limits are narrow, and the specific gravity and melting-point often 

 afford very valuable information as to the purity of the sample under 

 examination. 



Constituents. Beeswax consists principally of melissyl palmitate 

 (myricin), with which is associated free cerotic acid, an aromatic 

 body cerolein, and probably melissyl stearate. 



Cerotic acid, C 25 H 51 COOH(?), is an acid belonging to the formic acid series 

 the formula of which is not definitely established. It crystallises from alcohol in 

 granular colourless crystals melting at 78-79. Ceryl cerotate, C 25 H 5 COOC 26 H 53 , 

 occurs in Chinese wax, the produce of Coccus ccrifera> Fabricius (C. pela, 

 Westwood), and in wool fat. 



Melissyl palmitate, C 15 H 31 COOC 30 H 61 , is the palmitic ester of melissyl alcohol ; 

 the latter occurs in colourless crystalline needles melting at 85. 



Adulterants. Beeswax is liable to adulteration with solid paraffin, 

 with various fats and waxes of vegetable or animal origin, with resin, 

 stearic acid, &c. 



Paraffin and bodies belonging to this class are not attacked by hot, 

 concentrated sulphuric acid, whereas beeswax is entirely destroyed ; 

 hence if 5 grammes of beeswax are heated for fifteen minutes with 

 25 grammes of concentrated sulphuric acid to 160, and the mixture 

 afterwards cooled, rinsed with alcohol and then extracted with ether, 

 the latter solution should leave no appreciable solid residue on 

 evaporation. A better test for paraffin (and other foreign waxes) is 

 Weinwurm's which is performed as follows : 



Saponify 5 gm. of the wax by boiling it with 15 c.c. of N/l alcoholic 

 solution of potassium hydroxide and 15 c.c. of absolute alcohol, 

 evaporate to dryness, dissolve the residue in 20 c.c. of glycerin on 

 a water-bath, and add 80 c.c. of boiling distilled water ; a clear, or 

 at least translucent, solution should be obtained. 



Resin (colophony) would be readily dissolved by cold alcohol, 

 in which genuine beeswax is sparingly and only partially soluble. 



Soap would be removed by hot water, and the filtrate would 

 become cloudy when acidified with hydrochloric acid from separation 

 of the fat acid. 



Stearic acid, colophony, Japan wax (obtained from the fruits of 

 various species of RJius (N.O. Anacardiacece) , tallow, and all fats easily 



