crystalline. If no precipitate appears, or if the precipitate remains amorphous after a minute or two, the preparation is vigorously scratched with the glass rod. Generally speaking, much more characteristic and perfect crystals result upon scratching and upon the use of comparatively dilute alkaloidal solutions. The drop is examined under a low power. The colour, shape, crystal angles, polarization, extinction angles, and habit aid in the identification of the crystals under examination. The sensitivity was obtained by testing solutions of the alkaloid in decreasing concentration until one was reached that failed to give crystals with the reagent within 5 minutes. The dilution of the drop by the reagent solution must of course be taken into consideration. The form and behaviour of the crystals under polarized light are described and two plates of microphotographs are given. Strychnine shows the highest sensitiveness, crystals being obtained with a dilution of 1 : 20,000. Conine and heroin have the lowest sensitiveness, 1:50.

The test can be applied to very minute amounts of material. It affords a satisfactory microchemical test for the distinction of cinchonidine, cinchonine, and quinine. Brucine and strychnine are readily distinguished by this test, and cocaine can be distinguished from B-eucaine, stovaine, and heroin. (See also Y.B., 1922, 1, 2.)

Amorphous Alkaloid of Cinchona as Accelerator of Rubber Vulcanization. B. J. Eaton and R. O. Bishop. (J. Soc. Chem. Ind., 1922, 41, 374т.) It is found that the addition of a small quantity of "quinoidine or "amorphous alkaloid," which is at present practically a waste product of the preparation of quinine and the crystalline salts of the other cinchona bases, acts as an active accelerator to the process of vulcanization of rubber. It is considered that this by-product of the cinchona alkaloid industry may prove to be valuable for this purpose.

Anhalonium Alkaloids, Synthesis of Anholonidine and Pellotine. E. Spaeth. (Monats., 1923, 43, 477, through Chem. Abstr., 1923, 17, 1479.) The methods for the synthesis of these two bases is described; and the probable structure of the molecules discussed. (See also Y.B., 1922, 3.)

Atropine, Loss of, in Toxicological Examinations and Pharmaceutical Assays. P. Hardy. (J. Pharm. Chim., 1922, 26,

220.) In the course of extraction by the Stas-Otto method, the author finds that there is no loss of atropine by volatilization. There may, however, be loss by hydrolysis of the base: this occurs in aqueous solution to an appreciable extent at the normal temperature, and increases with a rise in temperature. In presence of NaOH this hydrolysis is more rapid than in presence of (NH)OH. These losses by hydrolysis may be rendered negligible, if not entirely avoided, by adopting Ogier's modification of the original Stas method. This, originally introduced to prevent emulsification of the immiscible solvents, consists in precipitating the albuminous matter, first with EtOH 95 per cent., then with absolute EtOH. The author's experiments show that under the conditions prescribed for the official assay of extract of belladonna in the French Codex 1908, there is no loss of atropine, either by hydrolysis or by volatilization. With reference to the alleged volatility of atropine, it is found that the dry base is not volatile at 100° C., nor is there any loss when solutions of the base in EtOH, Et2O or CHCI, are evaporated on the water-bath. Atropine is, however, distinctly volatile in the vapour of water. If an aqueous solution of the alkaloid is distilled in a vessel fitted with a splash trap packed with cotton wool, to intercept any spraying, and the aqueous distillate is shaken out with CHCl3, the CHCI, residue will give the characteristic mydriatic action of atropine and will respond to Vitali's reaction. These conditions, however, do not obtain in an ordinary toxicological process nor in a pharmaceutical assay.

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Caffeine, Extraction of. H. E. Watson, K. M. Sheth, and J. J. Sudborough. (J. Ind. Inst. Sci., 1922, 5, 177, through J. Soc. Chem. Ind., 1923, 42, 572A.) The solubilities of caffeine in a number of solvents at different temperatures are given, and it is concluded that CH, and especially C.H¿CH 3, are suitable solvents for commercial extraction of caffeine. CH. dissolves 5.18 Gm. at 77° C. and C,H,CH, 8.2 Gm. at 107° C. per 100 Gm. of solution. Caffeine is readily soluble in trichloroethylene and acetylene tetrachloride, but the ratio of the solubilities at 100° C. and 25° C. is lower than for the C.H hydrocarbons. When tea fluff is treated with a solvent not all the caffeine is dissolved, but a state of equilibrium is set up, owing to the adsorption of caffeine by the fluff. Average tea fluff is in equilibrium with a 1-3 per cent. aqueous solution of

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caffeine. If tea fluff is treated with CaO and five times its weight of water, only about 80 per cent. of the caffeine goes into solution. If 8 parts of C.H¿CH, at 100° C. is used as the solvent, only 8 per cent. of the caffeine is dissolved if the fluff has been dried previously, but if an alkali and a suitable quantity of water are present the proportion dissolved may be over 70 per cent. Caffeine is appreciably decomposed by prolonged heating with CaO at 90°-110° C. in the presence of water or a mixture of C.H.CH, and water. If the lime is replaced by MgO the amount of decomposition is lessened, while if Na,CO, is used the decomposition is very slight. Caffeine is not readily extracted from dry tea fluff by means of volatile solvents. Good yields can be obtained by adding an alkali, preferably Na2CO3, and water. Under these conditions 95 per cent. of the caffeine can be extracted on the small scale, using C,H,CH, as the solvent. For large-scale working a longer time is required, but this can be greatly reduced by increasing the supply of solvent and could probably be still further reduced by the provision of stirring gear in the extraction pots. A table is given showing the results of large-scale extraction experiments with "hydrocarbon" (condensed from compressed oil-gas; and C,H,CH, as solvents, and curves showing the concentration of caffeine in the solvents at various stages of the extraction. The extracted caffeine is purified from green colouring matter by treatment with basic lead acetate, recrystallized from hot water, and finally decolorized with 2.5 per cent. of decolorizing carbon. The direct recovery of caffeine from tea fluff by distillation with superheated steam does not appear to be a practicable process.

(Pharm.

Cinchona Bark, Determination of Total Alkaloids in. Zeit., 1923, 68, through J. Pharm. Belg., 1923, 5, 214.) Four Gm. of powdered cinchona is placed in a 100 c.c. flask with 38 Gm. of water and 2 c.c. of HCl 25 per cent. The flask is immersed in a water-bath, which is heated to boiling and kept at that temperature for 10 minutes. Then the hot liquid is rapidly filtered through a plug of cotton into a tared 100 c.c. flask and exactly 25 Gm. of the filtrate collected 2.5 Gm. of bark. When this is cold 20 Gm. of CHCl3, 38 Gm. of Et2O, and 5 Gm. of NaOH solution, 15 per cent. are added, and the mixture is well shaken for 15 minutes. If complete separation does not follow a short repose, 2 c.c. of EtOH 90 per cent. is added and the mixture again very gently agitated. After

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separation, the aqueous layer is removed as completely as possible by means of a pipette and the Et2O-CHCl, solution is transferred, through a small pad of cotton, to a tared Erlenmeyer 100 c.c. flask. The weight is taken; each 24 Gm. of solution 1 Gm. of bark. The solvent is then distilled off; the residue is moistened with 2 c.c. of EtOH, which is driven off at a moderate temperature, aided by gentle blowing. The residue is dissolved in 15 Gm. of warm EtOH, and the solution is diluted with water until it begins to show turbidity. Three drops of methyl red indicator are then added and the liquid is nearly neutralized with N/10 HCl. Water is then added to make the weight 50 Gm. and the titration is continued with N/10 HCl, each c.c. of which 0.0309 Gm. of total alkaloids. If a gravimetric method is desired the known weight CHCl3Et2O is shaken out with 15, 10, 10 and 10 c.c. of 1: 100 HCl. The bulked filtered acid liquid is shaken in a separator with 15 c.c. of CHCl3, treated with a slight excess of NH,OH, again shaken and the CHCI, separated into a tared Erlenmeyer flask. The alkaline liquid is again shaken out with 10 and 10 c.c. of CHCI,. The bulked solvent is distilled off, the residue dried at 70-80° C. and weighed as total alkaloids after 30 minutes in the desiccator. This method is the modification of that of Fromme employed by Cæsar and Loretz.

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Cinchona Ledgeriana Bark, Method for Approximate determining Alkaloids in. A. Groothoff. (Chemie et Indust., 1922, 7, 792.) The following method is used at the quinine testing laboratory established by the planters, for the determination of cinchona alkaloids in C. ledgeriana. Extract with Et2O a mixture of the well-ground bark with Ca(OH)2, NaOH solutions. Determine total alkaloids by dissolving the Et,O residue in N/HCl and titrating with N/NaOH, with litmus as indicator. Precipitate tartrates of quinine and cinchonidine, filter, wash, dry, and weigh. Determine optical rotation a and calculate quinine and cinchonidine from Cammelin's table. To the filtrate from the quinine and cinchonidine tartrates add NaI solution to precipitate quinidine, cinchonine, and amorphous alkaloids; separate the quinidine by means of 94 per cent. EtOH. Cinchonine alone is very seldom determined. The quinine sulphate content found by this method averages about 0-2 per cent. lower than that found by the method of the government plantations laboratory.

Clivia nobilis, Alkaloids of. E. Reeb. (J. Pharm. AlsaceLorraine, 1921, 129, through Bull. Sci. Pharm., 1922, 29, 163.) The author has isolated a crystalline alkaloid, clivianine, from Clivia nobilis. It is a glucosidal alkaloid and is accompanied by an amorphous base, which may be a decomposition product of clivianine. Both alkaloids are devoid of action on the frog and the guinea-pig. The name clivine is given to the amorphous base isolated by Molle from Clivia miniata.

Coca, Determination of the Benzoylecgonine, Tropacocaine and Ecgonine in. A. W. K. de Jong. (Indische Mercur, 1923, 46, 305, through Chem. Abstr., 1923, 17, 2471.) The CH, extract of the leaves is evaporated, treated with 1 per cent. AcOH and then with EtOH. It is again taken up in CH, from which the benzoylecgonine crystallizes. Ecgonine is determined in the remaining CH, solution by polarization. To determine tropacocaine 50 c.c. of the CH, extract of the leaf is shaken with 5 c.c. N/10 HCI, which is titrated with N/10 NaOH and litmus as indicator.

Codeine, Modified Method for Determination of. H. E. Annett and R. R. Sanghi. (Analyst, 1923, 48, 16.) The following is a simplified method based on that previously published (Y.B., 1921, 6). Eight Gm. of opium is triturated with 2 Gm. of Ca(OH), and 80 c.c. of water for half an hour, as in the B.P. (1914) process. Fifty c.c. of the filtrate (= 5 Gm. of opium) is extracted with three successive portions, each of 50 c.c., of C,H,CH3. The C,H,CH, from each successive extract is passed through a dry filter into a distillation flask. It is then concentrated under diminished pressure to a small bulk (about 25 c.c.), and dry HCl gas bubbled through it for half a minute. Codeine hydrochloride rapidly separates in a flocculent form, together with colouring matter, etc. The C,H,CH, 3 is filtered through a dry filter, the codeine hydrochloride dissolved in water and the solution filtered through the same filter into a small round-bottomed glass dish, a deep magenta colour developing. The liquid is then evaporated on the water-bath. When almost dry, the dish is transferred to a water oven and dried to constant weight. This treatment renders the colouring matter insoluble, as required in the next process. The substance is now dissolved in hot water and transferred to a 50 c.c. flask, the volume made up to 50 c.c., 0.2 Gm. of fresh