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mixed with these oils, whereas pure castor oil gives a clear solution. For testing purposes, 10 c.c. of the castor oil is poured into a 100 c.c. cylinder marked at 10 c.c. and 60 c.c. from the bottom, 50 c.c. of alcohol is added, the whole well shaken, and examined after being at rest two or three minutes; turbidity indicates the presence of at least 10 per cent. of other oils. Castor oil yields with sulphuric acid a substance soluble to a clear solution in 40 volumes of water, but this is the case even when it is mixed with 20 per cent. of olive or sesame oil; although these oils and other fatty oils yield milky solutions when treated in a similar manner. D. A. L.

Preserving Standard Tartar Emetic Solutions. By A. R. MILLER (J. Soc. Chem. Ind., 5, 464).—It was found that by excluding the air from the solution it was possible to keep it for any length of time without decomposition taking place. D. B.

Opium Analysis. By C. M. STILLWELL (Amer. Chem. J., 8, 295-308). The method differs from those of Flückiger and Squibb in a number of details. The sampling must be very carefully conducted and the whole made homogeneous by rolling with the hands on a slab of glass, in case the opium is soft; but by grinding with or without additional drying if it be hard. About 10 grams of the sample is broken up with 100 c.c. of water in a beaker, and when completely disintegrated allowed to remain some hours; a few drops of sulphuric acid may be added. The solution is filtered and the residue washed with about 20 c.c. of water, then returned to the beaker, digested for some minutes with 30 c.c. of water, again filtered, and this process repeated twice more. The washings are first concentrated at a gentle heat on a water-bath, then the stronger solution is added and the whole evaporated to about 25 c.c. When cold, 5 c.c. of alcohol (sp. gr. 0.82) is added, and the whole transferred to an Erlenmeyer's flask, using 5 to 10 c.c. of wash water; 5 c.c. of alcohol and finally 30 c.c. of ether are added with gentle shaking; any precipitate that may form is to be disregarded, as it is removed afterwards, 4 c.c. of ammonia solution (sp. gr. 0·960) is added, the flask closed with a cork moistened with ether, and at once shaken until the morphine separates, when it is allowed to remain 12 hours.

The ethereal layer is decanted on to a small filter, the flask rinsed several times with 10 c.c. of ether without shaking, and these rinsings also decanted on to the filter; the aqueous portion is then filtered, the crystals removed from the flask, and the whole washed with morphiated spirit (1 part of strong ammonia and 20 parts of alcohol, the whole saturated with morphine, namely, 0.33 per cent.); secondly, with morphiated water (containing 0.04 per cent.), again with morphiated spirit; and finally twice with 10 c.c. of ether to remove all narcotine. The paper is dried at 100°. The mother-liquor and the first washings of ether and morphiated spirit are treated with 3 c.c. of ammonia in a closed flask, and again allowed to remain to make sure of the precipitation being complete. The chief impurity in the morphine so obtained is calcium meconate, and some organic matters insoluble in water and alcohol; the purification is effected by treating

the dried and weighed precipitate with hot alcohol of 95 per cent. ; after removing the bulk of it to a beaker, the paper and residue, after thorough extraction with hot alcohol, are dried and weighed, thus giving the weight of the pure morphine. H. B.

Estimation of Quinine Sulphate. By G. VULPIUS (Arch. Pharm. [3], 24, 1022-1023).-The method described is identical with that given in the next Abstract.

Quinine Chromate in Analysis. By J. E. DE VRIJ (Arch. Pharm. [3], 24, 1073).-4 grams of quinine sulphate is dissolved in 400 grams of boiling water; to this is added 1 gram of potassium chromate dissolved in a little water; after remaining some hours quinine chromate separates in anhydrous crystals of the composition (C20H21N2O2)2,H,CrО; it is soluble at 14° in 2733 parts of water, and at 16 in 2000 parts.

For the estimation of cinchonidine in quinine sulphate, 5 grams of the sulphate is dissolved in 500 grams of boiling water, 12 grams of potassium chromate dissolved in a little water added, and the whole allowed to remain until next day, when the quinine chromate is collected on a filter and washed. The mother-liquor and washings are heated with soda on a water-bath for some time, whereby the cinchonidine separates out in the crystalline form, and is collected, dried at 160°, and weighed. The author found in 5 grams each of three commercial samples, 0·197, 0·205, and 0·244 gram of cinchonidine respectively.

To determine the amount of pure quinine in the sulphate, 2 grams of the sulphate was taken and treated as above with 0.5 gram potassium chromate. The precipitated chromate was weighed, and this weight was increased by 005 gram for each 100 c.c. of motherliquor and wash-water. From the total thus obtained, the amount of quinine is easily calculated.

J. T.

Neutral Quinine Chromate. By O. HESSE (Pharm. J. Trans. [3], 17, 585 and 665). Recently De Vrij (preceding Abstract) recommended a process for estimating quinine in the sulphate, it was based on the formation of quinine chromate, which was washed, air-dried, and weighed as (C20H2N2O2)2,H2CrO,. The author of the present communication now points out that the air-dried sample contains, in addition to the above, 2 mols. H2O. It becomes anhydrous at 80°, at higher temperatures decomposes. In a note, the Editor of the above Journal points out that the dry salt rapidly absorbs moisture from the air, and attains the same weight it had before drying. For this and another reason, the large correction required for solubility, the method is not recommended.

In the second paper, it is shown that hydroquinine and cinchonidine, when present in quinine sulphate, cannot be correctly determined by De Vrij's chromate method, for although the neutral chromates of these two substances are more readily soluble than quinine chromate, yet they cannot be separated from the latter by crystallisation, as they crystallise out with the quinine chromate. In fact, where quinine

sulphate contains 8 per cent. or less of hydroquinine, the latter behaves exactly like quinine; whilst in the presence of 0.3 per cent. of cinchonidine, the mother-liquor from the quinine chromate yields a precipitate consisting not wholly of cinchonidine, as is supposed by De Vrij, but for the most part of a compound of seven molecules of cinchonidine with one molecule of quinine; also when the percentage of cinchonidine exceeds 0:3, the mother-liquor not only behaves in the same way, but a varying quantity of cinchonidine chromate crystallises with the quinine chromate. The mixture of chromates obtained on treatment with ammonia and ether yields the compound C20 H24N2O2, 2C19H22N2O, which by crystallisation from hot dilute alcohol can be converted into large, brilliant, rhombohedrons of the formula C20H24N2O2, 7C19H22N2O. D. A. L.

Quinine Sulphate. By E. JUNGLEISCH (J. Pharm. [5], 15, 5-18). -A criticism of methods of assaying quinine sulphate, showing that the methods given in the Codex of 1884, after Kerner and others cited, are more or less unsatisfactory. J. T.

Detection of Rosaniline Salts and Sulphonated Rosaniline. By A. LIEBMANN and STUDER (J. Soc. Chem. Ind., 5, 287).-Schiff's researches (Compt. rend., 64, 487) have shown that aldehydes give an intense violet coloration with a solution prepared by treating rosaniline salts with sulphurous anhydride. Schmidt (Abstr., 1882, 179) confirmed the general application of this reaction, and showed that acetone produced the same violet tint. The authors have successfully applied this reaction to the detection of aldehydes or acetone in the urine of persons suffering from diabetes. They have found that this property of the aldehydes and of acetone can be applied inversely for the detection of rosaniline salts and sulphonated rosanilines in dyes, wines, and lozenges. This test is exceedingly delicate, a distinct reaction with acetone being obtained, for instance, when cudbear is adulterated with only one-fortieth per cent. of rosaniline.

D. B.

Detection of Acid Coal-tar Colours in Wine. By J. H. de REGO (Chem. Centr., 1886, 842-843).-Girard's process in its original form fails to detect acid coal-tar dyes, but it can be used by filtering whilst the mixture is still acid.

The following method is very serviceable for red dyes, but not for others-10 c.c. of the wine is nearly neutralised with a 5 per cent. potash solution; a saturated acid solution of mercuric acetate is added until the mixture is greenish, and it is then filtered. If the wine contains an acid dye, the filtrate will be coloured, and the colour will become more intense on adding hydrochloric acid; if otherwise, the filtrate will be yellowish, and will become paler with acid. A deep yellow filtrate, becoming red with hydrochloric acid, may be obtained from a pure wine if the process be varied.

A much more sensitive test is the following:-To 5 drops of the wine, if a strongly coloured Portuguese wine, or about 1 c.c. of any other wine, add a solution of manganous sulphate in strong hydrogen peroxide, then 2-3 drops of 10 per cent. ammonia, heat to boiling,

and filter. A colourless filtrate is obtained, which, if acid dyes be present, assumes a red colour on addition of hydrochloric acid. Basic coal-tar colours give at once a coloured filtrate. If too much wine is employed the filtrate will not be quite colourless.

The author, however, prefers the following process:-To 15 c.c. of the wine add sufficient barium peroxide, then pass carbonic anhydride until the mixture assumes a chocolate colour, but not longer. It will then give a perfectly colourless filtrate, which, on addition of hydrochloric acid, will exhibit characteristic colours if acid dyes are present. M. J. S.

Reactions for Discriminating between Chrysophanic Acid and the Santonin Colouring Matter in Urine. By G. HOPPESEYLER (Chem. Centr., 1886, 746).-Aqueous soda produces a red colour in urine containing both the santonin colouring matter and chrysophanic acid. In the former case, the red colouring matter is easily soluble in amyl alcohol, and gradually changes to yellow in contact with atmospheric oxygen, whilst in the latter case the red colouring matter is insoluble or almost insoluble in amyl alcohol, and persists for a very long time. These colours differ also in spectroscopic properties. J. P. L.

Quantitative Reactions for the Separation of Some Resins. By M. V. SCHMIDT and F. ERBAN (Monatsh. Chem., 7, 655-672).— The authors have applied the methods of Köttstorfer (Zeit. anal. Chem., 18, 199) and of v. Hübl (Dingl. polyt. J., 253, 281) for the detection of fats, to the examination of resins, and are enabled to determine the relative amounts of the various resins in a mixture without actual separation. The resins are identified by (1) the amount of potash required to saturate 1 gram of the resin dissolved in alcohol; (2) the amount of caustic potash which combines with 1 gram of the resin when the latter is boiled with an excess of alcoholic potash solution; (3) the percentage of iodine which the resin is capable of taking up. The methods for determining these data are given, and also a table in which are the numbers already determined for the various resins.

In the examination of solutions of resins in alcohol or in turpentine, the liquid is first steam distilled until the distillate shows no acid reaction. The residue is dried at 110°. A systematic method of fractional separation of the resins by means of solvents is described in detail. Tables are also given showing the solubility of resins.

N. H. M.

Test for Tannin. By J. E. SAUL (Pharm. J. Trans. [3], 17, 387). -The substance is mixed with water, a few drops of an alcoholic solution of thymol are added, and then concentrated sulphuric acid. Commercial tannin yields a rose-coloured turbid solution, pyrogallol a dull-violet solution, whilst gallic acid remains colourless, or nearly D. A. L.

So.

Separation of Globulin from Albumin in Urine. By A. OTT (Chem. Centr., 1886, 540).-The author points out that the separation of globulin from albumin in urine by saturation with magnesium sul

phate, is only complete in those cases where at least one-half of the phosphoric acid is in the form of neutral phosphate, otherwise the urine should be brought to this condition by the addition of alkali. 60 grams of magnesium sulphate is added to 50 c.c. of urine, and the solution allowed to remain 24 hours at 30-35°, being shaken occasionally. When these precautions are observed, the results are trustworthy. C. F. C.

Detection of Traces of Albumin. By R. PALM (Zeit. anal. Chem., 26, 35-38).-The sensitiveness of the test for albumin depending on its precipitation by an acid, can be much increased by dissolving the acid in alcohol, or, better, alcohol containing 10 per cent. of ether; an excess of the reagent will not then redissolve the precipitate.

Sodium sulphantimonate added to an albumin solution made alkaline with ammonia, gives a yellow precipitate. Sodium nitroprusside acidified with acetic acid, and also potassium antimonate, are sensitive reagents, but all three give precipitates with the alkaloïds. The following are free from that defect:-(1.) An alcoholic solution of ferric acetate, previously rendered basic by heating with excess of recently precipitated ferric hydroxide. (2.) An alcoholic solution of basic cupric acetate. The precipitate dissolved in acetic acid and boiled with excess of soda, shows reduction in presence of albumin. (3.) An alcoholic solution of lead acetate or chloride; or (4) a solution of freshly precipitated lead hydroxide in water. This last will detect 1 part of albumin in 500,000 of water. The colourless precipitates from (3) and (4) are adapted for confirmation by Adamkiewicz's test (violet colour on mixing with glacial acetic and sulphuric acids). M. J. S.

Presence of Albumin in Vegetable Tissue: Microchemical Test for Albuminoïds. By F. KRASSER (Monatsh. Chem., 7, 673— 697). The various colour tests for albumin are discussed and shown to be insufficient, as they are also produced by substances other than albuminoïds. When albuminoïds are treated with alloxan an intense purple coloration is produced; the colour is also produced by tyrosine, aspartic acid, and asparagine. The reaction must take place in the cold and the mixture be kept free from ammonia. In testing for albumin, the substance is first washed with hot water to remove other compounds present which give the reaction with alloxan. Millon's reagent (Compt. rend., 28, 40) is the only one which shows a definite structure in albumin; namely, the presence of a monohydroxylated aromatic nucleus. The reaction has the drawback that it will not take place in the case of a tissue containing much water, owing to the formation of basic mercury salts. In testing for albumin by this method in cellular tissue, the absence of vanillin (the only other substance containing a monohydroxylated aromatic ring which has as yet been found to be present) is determined by Wiesner's phloroglucinol reaction; it is still better to wash the section to be tested with warm water.

The author's methods for detecting albumin consist (1) in showing

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