FOOD AND DRUGS ANALYSIS 243 ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. FOOD AND DRUGS ANALYSIS. Estimation of Phenaeetin when mixed with Acetanilide. 8. Miller. (Amel.. J . Pha~m., 1917, 89, 156.)-The method is based on &he well-known nitric acid test for phenacetia of Autenreith and Hinsberg (ANALYST, 1891, 17, 561, which gives an intense yellow t o orange colour, and also upon the facts that phenacetin is soluble in methyl alcohol, and upon the addition of nikric acid to the suitably diluted solution the yellow colour is produced which, when compared in Nessler tubes with a standard phenacetin solution in methyl alcohol, serves to measure the amount present.Since methyl alcohol decreases the intensity of the COIOUT, the same amount of the solvent must be arranged for in each tube compared.H. I?. E. H. Estimation of Novaspirin, alone or when mixed with Aspirin. R. Miller. (Amer. J. Pharm., 1917, 89,155.)-The method depends upon the fact that sodium hydroxide produces a yellow colour with novaspirin, but remains colourless with aspirin. The aspirin must not be present in a greater proportion than 2 parts of aspirin to 1 of novaspirin, or it interferes with the productiun of the yellow colour.Standard dilutions of novaspirin in 95 per cent. alcohol are made and compared with the substance under examination, $ caustic soda being employed in the cold to produce the colour. H. 3’. E. H. Estimation of Milk-Sugar in Headaehe Powders. R. Miller. (Amer. J Pharm., 1917, 89, 154.)-The method depends on the fact that milk-sugar when heated with ammonia gives a yellow to red colour, the intensity of which is used to measure the amount of sugar present.Standard dilutions representing from 5 to 25 mgrins. of milk-sugar are made, fo which are added 10 C.C. of strong ammonia. These and the material under examination are then heated in a water- bath to about 9 5 O C. for half an hour, and $he colours produced compared in Nessler tubes, the fin81 volumes in all cases being brought to 50 C.C.The powders should be previousIy extracted with a mixture of chloroform and alcohol to remove acetanilide, phenacetin, etc. H. F. E. H.244 ABSTRACTS 02 CB1F.MTCAL PAPERS Analysis of Desiccated Milk. C. Pomher. (Ann. Falsific., 1917,9,450-4a0)- Moistum.-To prevent cwamelisation it is best to estimate the moishre by drying the powder at 400 to 4(io C.over phoephorus pentoxide. There is xm advantage in speed in using a temperature of 60° fo 70° C., the drying being almost complete at the lower temperature within forty-eight hours, or, if great accuraey is required, within seventy-two hours. Fat.-The method of extracting the fat with ether gives too law results, even when the extraction is continued for eight hours.The method of Riige-Gottlieb as modified by Richmond (ANALYST, 1908, 83, 389) gives better results. For example, in the analysis of fifteen samples of desiccated milk of various origin the dserence in the proportions of fat yielded by the two methods was usually over 1 per cent., and in one case was 340 per cent. Only one sample showed the mme results (within 002 per cent.) by the two methods.C. A. M. Estimation of Theobromine. L. Debourdeaux. ( J . Pha~m. Clzim., 1917, 16, 306-311.)-Maupy hae described a method (ANALYST, 1897, 23, 191) in which theobromine is separated from cocoa by extraction with a mixture of phenol and chloroform, evaporation of the solvent, and precipitation with ether ; theobromine is insoluble in ether, whilst caffeine, colouring matter, and fat, are soluble.The precipitate of theobromine thus obtained is collected and weighed. It still con- tains from 6 to 12 per cent. of impurity, and the author therefore amplifies the method with the object of obtaining a residue of pure theobromine. One hundred grmr~. of the cocoa are mixed thoroughly with 40 C.C.of water (the addition of water is neoesszwy, since phenol-chloroform does not extract the alkaloid from dry cocoa), and the moist mass is boiled under a reflux apparatus for two hours with a mixture of 60 grms. of crystallised phenol and 340 grms. of chloroform; after coollng, the solution is filtered, and the extraction with phenol-chloroform is twice repeated. The chloroform is then separated from the extract by distillation, and the dry residue obtained is mixed with 900 grms.of ether; after about eighteen hours the precipitated theobromine is collected on a filter, washed with a small quantity of ether, the filter and precipitate are boiled for a few minutes with a mixture of 20 grms. of sulphuric acid (sp. gr. 1.842) and 180 grms. of water, and the solution is filtered into a flask containing 250 C.C.of ammonia (sp. gr. 0924), the filter being washed with hot dilute sulphuric acid. To the arnmoniacal solu- tion are added 3 grms. of silver nitrate, the solution is evaporated untii all the free ammonia has been expelled, then diluted to 500 C.C. and set agide overnight. The silver-theobromine compound is collected, washed with about 250 C.C.of water, then mixed with 50 C.C. of water and decomposed with hydrogen sulphide; 600 C.C. of amyl alcohol are now added, and the whole mixture is distilled until about 200 C.C. of distillate (water and amyl alcohol) have been collected. The residual amyl alcohol solution in the flask is filtered while hot, the insoluble p o ~ o n is washed with boiling amyl alcohol, and the filtrate is set aside at 1 5 O C.for thirty-six hours. The crystalline mass of theobromine which sepmabs out is col- lected on a filter, washed with ether, dried at 100° C., and weighed; the weight of the amyl alcohol must be noted and a correction applied for the solubility of theBACTERIOLOUICAL, PHYSIOLOGICAL, ETC. 245 crystals, since 1,000 grms. of amyl alcohol at 1 5 O C. dissolve 0.200 grm. of t h o - bromine. The method has been applied to various cocoa products, and found to give t,rustworthy results. It is unnecessary to remove the fat previous to the estimation of the theobromine; when only small quantities of tlieobromine are present the amyl alcohol solution may be concentrated to a smaller volume than that mentioned. MT. P. s.