858 



FOODS AND FOOD ADULTERANTS. 



mined the fatty alcohols and hydrocarbons iu beeswax in an essentially similar way 

 long before MM. Buisine, whose principal service consists in having simplified the 

 apparatus and accurately studied the conditions of success. The principle of the 

 method lies in the fact that fatty alcohols are converted into fatty acids on fusion 

 with caustic potash, hydrogen being evolved. Saponified wax is heated with potash 

 lime and the liberated hydrogen measured. The melt is pulverized, the hydrocar- 

 bons extracted by solvents and weighed. 



I have estimated the hydrogen by this method on several samples and have gotten 

 numbers somewhat lower than those of Buisiue. As, however, the estimation of the 

 hydrocarbons was of more interest to me, I did not follow the matter farther. I have 

 however observed that the gas evolved does not reach a constant volume until after 

 three hours' heating, instead of the two prescribed by Buisine. On the completion of 

 the operation the flask is taken from the apparatus, allowed to cool, broken, the sin- 

 tered mass powdered and, with the fragments of the flask, placed in a Soxhlet ex- 

 tractor, extracted for several hours with petroleum ether, the excess of ether distilled 

 from the extract, and the latter dried at 110 and weighed. Unadulterated beeswax 

 always contains hydrocarbons. Schwalb * claimed the amount of these to be about 

 6 per cent. Buisiue found between 12.5 and 14, and the numbers which I have ob- 

 tained, excepting for two samples (Nos. 15 and 21 in the following table), fall be- 

 tween these. 



The numbers obtained are found in the following table : 



, r== s- 



t 



On inspection of the above it will be seen that, with exception of Nos. 15 and 21 

 the hydrocarbons vary only between 12.5 and 14 per cent. Taking these results as a 

 standard, it follows that this method permits determination of added hydrocarbons 

 when in amount greater than 2 per cent. Using the average figure, 13.50, the amount 

 of ceresin added to a beeswax can be obtained' according to the formula 



100 (K k) 



100 K 



" Lieb. Ann. Chem., 1886, 23o, 149. 



