836 FOODS AND FOOD ADULTERANTS. 



to be pure and 3 parts of lard was made and treated as above. No precipitate was 

 obtained with HC1. Mixtures of wax and Japan wax, wax and tallow, and wax and 

 resin also yielded negative results, whence the author concludes the products of sa- 

 ponification are not soluble in alkali as strong as that prescribed. To prove this he 

 boiled 5 grams of common yellow soap with 50 cc. of "solution of soda" (specific 

 gravity 1.18) for half an hour, cooled, filtered and acidified as above. No precipitate 

 was formed. 



The Pharmacopoeia test for paraffin (also ceresin) reads: "If 5 grams of wax be 

 heated in a flask for fifteen minutes with 25 grams of sulphuric acid to 160 C. and 

 the mixture diluted with water, no solid, wax-like body should separate (absence of 

 paraffin)." In working this method it is found advantageous to use a tall 8-ounce 

 beaker and to gradually heat the mixture on the steam bath, taking great care to 

 stir it at first, as the reaction is liable to become unmanageable. 



When the violence of the action is over raise the heat gradually to about 100 (in- 

 stead of 160) and keep it there for an hour and a half, stirring occasionally. Allow 

 to cool gradually. When quite cold the paraffin will be found as a layer on top of 

 the seinisolid mass. Carefully remove and wash with water to remove as much as 

 possible of the charred wax. Again heat with about 15 grams of sulphuric acid for 

 about an hour. On cooling the paraffin may be again detached, washed, dried, and 

 weighed. Trial with a known mixture containing 20 per cent paraffin gave 125 mil- 

 ligrams paraffin from 1 gram (=200 milligrams paraffin). 



A trial with a known mixture gave good results. 



Morse found 20 samples of pure wax to be below 0.96 specific gravity. Prof. Bed- 

 ford * gives another method resting on the use of sodium carbonate in dilute solu- 

 tion. Saponifiable bodies if present in the wax give emulsions. The author prefers 

 the concentrated solution of Donath. 



The London Pharmaceutical Journal t says: "Resin may be estimated by treat- 

 ment with cold alcohol." A sample of wax of known purity yielded 6 per cent to 

 cold alcohol, and 5 commercial samples an average of 5.6 per cent. Brodiet and J. 

 F. Babcock$ say pure wax contains from 4 to 6 per cent of cerolein, which is soluble 

 in cold alcohol. The foregoing test is therefore useless except with large quantities. 

 Another test tried was : || Melt 1 gram of wax with 3 drops concentrated sulphuric 

 acid. A red color is produced in the presence of resin. On hardening, the wax as- 

 sumes a violet shade. Trials with known mixtures of resin and wax gave the reac- 

 tion, there however being no difference as to intensity of color between samples of 

 wax with 5 and 15 per cent of resin. Pure wax did not give the reaction. Nine of 

 the 87 samples of commercial wax gave the color. The author found that differ- 

 ences of 2 per cent could be distinguished by the depth of color produced. This was 

 true up to 12 per cent resin, above which it required a difference of 4 per cent to 

 make a perceptible change in the tint. The test indicates the presence of 0.25 per 

 cent resin. 



By heating 1 gram beeswax with 10 cc. of saturated solution of borax at 80 and 

 cooling the aqueous solution becomes turbid. In presence of Japan wax or stearin a 

 milky solution is produced remaining opaque after cooling. Pure wax gave a turbid 

 solution ; a mixture of wax and Japan wax rendered the solution milky, and on cool- 

 ing left a light flocculent mass, occupying neaily the whole bulk of the solution ; a 

 mixture with stearin gave a white emulsion ; a mixture with paraffin behaved like 

 pure wax and one with spermaceti gave a milky solution. On diluting each of these 

 teats with 5 volumes of water at 80 and briskly shaking, that containing the stearin 

 mixture was opaque as before, with a light curdy mass on the surface ; that contain- 



* Proc. Amer. Pharm. Assoc., 1877, 144. 



t September, 1870. 



t Phil. Trans., 1878; Miller., Elements of Chemistry, ill ; 263. 



Proc. Amer. Pharm. Assoc., 1867, 374. 



l|Araer. Jour. Pharm., 1881, 307. 



