CHARACTER OF SAMPLES OF BEESWAX SUBMITTED WITH 



BIDS. 



By L. F. KEBLER and F. M. BOYLES 

 INTRODUCTION. 



On account of the great variation in price, the uncertainty as to 

 the quality of the samples, and the fact that if an award was made on 

 an adulterated sample it would constitute the basis of purchase 

 for a year, the departmental general supply committee referred 26 

 samples of beeswax, submitted with bids, to the Bureau of Chemistry 

 for examination. The results given in the accompanying table 

 clearly show that the price is not a reliable index as to quality. In 

 fact, the sample of white beeswax for which the highest price was 

 asked, namely, 60 cents a pound, was adulterated, not only with 

 paraffin but with stearic acid as well. The prices quoted for yellow 

 beeswax varied over 100 per cent, from 18 to 38 cents per pound, 

 and for white beeswax the range is still greater, namely, 24 to 60 

 cents, yet some of the high-priced as well as some of the low-priced 

 products were adulterated. Of the 26 samples examined, 53 .8 per cent 

 were adulterated. The more common adulterants were paraffin and 

 ceresin ; artificial coloring was detected in only one case. The exami- 

 nations were made by the following methods : 



METHODS OF ANALYSIS. 



Specific gravity. Drop the melted wax by means of a stirring rod onto a moist, 

 cool, smooth porcelain surface in such manner as to obtain globules about one-eighth 

 of an inch in diameter; allow to cool for from 2 to 24 hours, then place in a suitable glass 

 cylinder of about 200 cc capacity and add a cooled mixture of alcohol and water 

 having about the specific gravity of beeswax. If the globules sink, add water; if they 

 rise to the surface, add alcohol. The water or alcohol is added with repeated agitation 

 until the globules float indifferently in the mixture at the desired temperature. 

 The specific gravity of the mixture is taken at this point with a pyknometer. 



Melting temperature. Thinly coat the bulb of a thermometer with wax and allow 

 it to stand 24 hours. Place the bulb of the thermometer in a large test tube, holding it 

 in place by a stopper grooved on the sides so as to allow free access of air. Immerse 

 the test tube containing the thermometer in a beaker of water and raise the tempera- 

 ture very gradually (1 degree in from two to three minutes). The temperature at 

 which a transparent drop forms on the end of the thermometer bulb is taken as the 

 melting point. 



Acid, ether, and saponification numbers. Place 5 grams of the wax in a 200 cc Erlen- 

 meyer flask with about 25 cc neutral alcohol and heat on the water bath until the 

 mixture is entirely melted. Then add 1 cc of phenolphthalein solution and titrate 

 the free acid quickly with seminormal alcoholic potash. Add 50 cc more of the 



49 



