848 FOODS AND FOOD ADULTERANTS. 



By substituting the values of X, Z, Y, and W in equation 4, are obtained the equa- 

 tions : 



Y = 362,954 2.391 A 1.518 B 

 14.151 



X = 25.694 (0.1689 A + 0.1703 B) 



In this way is obtained the per cent of cerotic acid. This multiplied by 6.117 

 gives the myricin, the sntn of both being the per cent of wax in the mixture. De- 

 ducting the real cerotic acid from A, and dividing the residue by 1.518, gives the per 

 cent of fatty acids. The real myricine deducted from B, and the result divided by 

 2.391, gives the true per cent of fat. Thus are found the per cent of the paraffin- 

 free mixture. An- artificial mixture of 80 per cent wax and 20 per cent lard, gave, 

 wax, 80.42 per cent (cerotic acid, 11.30 per cent, myricine, 69. 12), and fat, 19.58 (fatty 

 acid, 0.46. and fat, 19.07). 



One of the samples of comb foundation alluded to gave 8.35 per cent of cerotic 

 acid and 35.67 of myricin. It contained much paraffin. Assuming the absence of 

 fat, the composition of the samples calculates : Cerotic acid, 5.83 per cent ; myricin, 

 35.67 (together equaling 41.50 per cent) ; fatty acid, 1.66 per cent, and paraffin, 56.84. 

 Another foundation gave cerotic acid, 11.99 ; myricin, 73.36 (together, 85.35 per cent 

 wax) ; fatty acid, 4.31 per cent ; paraffin, 10.34 per cent. The paraffin of commerce 

 generally contains a small proportion of fatty acid, added to diminish its transpa- 

 rency, whence probably the slight proportion found above. A paraffin candle con- 

 tained 12.4 per cent of fatty acids. 



A light yellow sample of wax, warranted genuine by the vendor, gave 10.47 per 

 cent of cerotic acid, and 69.30 per cent myricin. From this it follows that the sam- 

 ple consists of wax 79.77 per cent and paraffin 20.23. Another sample obtained by 

 purchase gave wax 70.60 per cent, fatty acid 5.42 per cent, and fat 24.38. It was 

 free from paraffin. 



In conclusion, Hehner warns analysts against adopting his figures in working on 

 bleached wax. In a discussion of the paper before the Society of Public Analysts, 

 the president, Mr. Wigner, stated that many of the combs received from America 

 were entirely artificial. Dr. Muter said that paraffin was practically the only adul- 

 terant used in wax. 



About a half a year later than Hehner, but apparently independently, Hiibl* pub- 

 lished a wax method based on a similar principle. He heated 3 or 4 grams of the 

 substance with about 20 cc. neutral, 95 per cent alcohol, titrated hot with seminor- 

 mal potash and phenolphtaleiu to estimate free acid, added 20 cc. more of potash and 

 saponified by gentle boiling for about forty-five minutes on the water bath without 

 the use of mercury pressure. Excess of alkali was titrated with semiuormal hydro- 

 chloric acid. Hiibl called the number of milligrams of potash required to saturate 

 the free acid of 1 gram of wax the "acid number," that required to decompose the 

 wax ethers the "ether number." According to his experiments, which were not 

 numerous, the potash required to neutralize the free acids of 1 gram of wax is equiv- 

 alent to 19 to 21 milligrams ; that for the ethers, 73 to 76. The relation of the acid to 

 the ether numbers varied between 1.36 and 1.38. For the complete saponificatiou 

 Hiibl took between 92 and 97 milligrams of potash. 



Dingl. polyt. Jour., 249-338. 



