THE ANALYST. 125 ORGANIC ANALYSIS. On Nicloux’s Method of determining Alcohol. M. E. Pozzi-Escot. (Ann. de Chim. anal., 1902, vii., 11, l2.)-Nicloux’s method is a colorimetric one based upon the reducing action of alcohol upon potassium bichromate in an acid solution (ANALYST, xxii., 161 and 263). The author has made a series of experiments with this method, and finds that all the alcohols met with in fermented liquids behave like ethyl alcohol towards the reagent, and that aldehyde, contrary to Nicloux’s assertion, has also a reducing action. In order to obtain comparable results, even with absolutely pure ethyl alcohol, it is essential to maintain absolutely identical conditions, and even then the author has obtained discordant figures in duplicate experiments. C. A. M.Detection and Estimation of Anthranilic Methyl Ester. E. Erdmann. (D. Chem. Ges. Ber., 1902, xxxv., 24; through Chern. Zeit. Rep., 1902, 40.)-This126 THE ANALYST. ester has been found in essential oils, and is best determined by the use of such reagents as give azo colouring matters with primary aromatic amines. Any oolour- ing matter soluble in water may be employed-e.g., the combination with @naphthol- disulphonic acid R-and the operation can be made quantitative by colorimetry. If, however, only small quantities of the ester are present, the author prefers to dilute the diazotized solution to a known volume, and then to titrate it with an alcoholic solution of @-naphthol. The colouring matter thus falls in an insoluble condition, and the end-point of the titration may be ascertained either by (' spot " tests or by filtering off a little of the liquid and trying it with both the diazo com- pound and with naphthol. The precipitate is orange-coloured, dissolving in strong sulphuric acid to a red-violet, Even a few milligrammes of anthranilic methyl ester may be determined in this manner, and the presence of the corresponding compound of methylanthranilic acid does not interfere.F. H. L. A Modiflcation of Zeisel's Method for the Estimation of Methoxyl Groups. J. T. Hewitt and T. S. Moore. (Proc. Chem. SOC., xviii., 10.)-The authors describe a modification of Zeisel's method, in which the condenser supplied with water at 40" is replaced by a fractionating column. The potash bulbs, containing water and red phosphorus, are dispensed with, and the time taken in fitting up the apparatus and carrying out the operation is much less than in Zeisel's original method.A. G. L. On the Determination of the Methoxyl- Group in Substances containing Sulphur. (Monatshefte f. Chem., xxii., 1105.)-It is well known that Zeisel's method yields low results when applied to substances containing sulphur. The following method is applicable to those cases in which the methoxyl- group can be removed by saponification-that is, to the esters of methyl alcohol : The substance and 3 to 6 C.C. of solution of KHO (specific gravity 1.27) are placed in a small distilling flask, the side-tube of which communicates with a U-tube con- taining pieces of pumice heated after soaking in copper sulphate solution, which serves t o dry the methyl alcohol.The other end of the U-tube is fitted to a Winkler absorption flask by means of some arrangement which prevents the passing back of the liquid. This flask contains hydriodic acid (specific gravity 1*7), and is connected to the Zeisel apparatus. During the determination a current of purified air is drawn through the whole apparatus, and two small distilling flasks are used as receivers for the methyl iodide, the side-tube of the second of the flasks being connected with the pump. At the commencement of the operation the air current is started, the U-tube warmed to 80" to go", and the Winkler flask cooled by a mixture of ice and salt. The flask containing the substance is then slowly heated, by means of an oil-bath, until a gentle boiling commences, which is allowed to continue until the contents of the flask are dry, or nearly so.The flask is then allowed to cool, a further quantity of solution of KHO introduced, and the heating renewed until the contents of the flask are again dry. The freezing mixture is then removed from the Winkler flask, Felix Kaufler.THE ANALYST. 127 which is allowed to stand at the room temperature for half an hour, after which it is carefully heated to 140" to 150°, and kept at this temperature until the methyl iodide has been completely distilled off, the current of air being continuously main- tained. Up to this point the determination requires three to four hours; the remainder of the process is exactly as in Zeisel's method. From the test analyses it appears that the results furnished by the method are satisfactory for all practical purposes.In conjunction with Zeisel's method it might be used to differentiate between saponifiable and non-saponifiable methoxyl-groups. A. G. L. The Adulteration of Turpentine witah '' White Spirit." A. and P. Andouard. (Journ. Pharm. Chim., 1902, xv., 99-lOl.)-The authors state that the adulteration of turpentine with light petroleum oil is now very prevalent in France, a special product being imported from America for the purpose under the name of "White Spirit ." A specimen of this substance examined by the authors had the following char- acteristics : Colour, violet-blue fluorescence ; specific gravity at 15" C., 0.807 ; rota- tion in 200-millimetre tube, - 1.2" ; boiling-point, 150" to 160" C., leaving a residue of 42 per cent.beginning to boil at 205" C., and having a rotation of - 0.2". The following results were obtained with a sample of pure turpentine and with six commercial samples thus adulterated : __ - _--_- ___- ___._I_ - - _ _ ~ Specific Gravity Residue at Rotation of ' Rotation 1 15" c. Per Cent. Substance. Residue. at 1 205" c. Original of I_-- -- Pure turpentine ... ... -I 0.871 --I 6 -63.1 ' -6.4" Turpentine adulterated with 1 white spirit ... . . . 0.860 to 0.8671 16 t o 21 , - 52.2 to 57.3 - 8.0" to 9.6" The authors call attention to the curious fact that the optical rotation of the residue from the adulterated samples was higher than that obtained from the pure turpentine, whilst the contrary was to have been expected.For a quantitative determination of the added substance, they recommend the destruction of the turpentine hydrocarbons by means of fuming nitric acid, which leaves the mineral oil practically unaltered. C. A. M. Chemical Composition of Norwegian Wood Tar. J. A. Mjoen. (2eits.f. angew. Chem., xv., 97.)-A. The retdrt tar is made in factories from the sawdust of pine-wood together with some fir-wood. These are soaked in water for some time, then dried. The tar is distilled off in the absence of air, and is a by-product in the manufacture of wood vinegar. The tar is brownish-black to black in colour, has an acid reaction, a penetrating smell, and a specific gravity of 1.07. B. In the manufacture of charcoal-burner's tar the wood is partially burnt in a furnace through which a current of air passes.Consequently a large portion of the128 THE ANALYST. volatile constituents is lost. In colour it resembles the retort tar. It has a weak acid reaction, an aromatic smell, and a specific gravity of 1.06. In consistency it is thicker than retort tar. - - __- --_ A. Norwegian Retort Tar made from Sawdust of Firs and Pines. , - - - - . - __ Aqueous solution ... I Acetone ... . . , 0.4 Total aldehydes add ketones1 - Acetic acid . . . . . . 0'36% Total fatty acids . . . . . . acids de- tected : acetic, i propionic, bu tyric. valeric Guaiacol and creosote ... creosote about 20% Total phenols and phenol derivatives . . . . . . i - Retene . . . . . . . . . not detected Pitch . . . . . . . . . - Total hydrocarbons ... - Esters .. . . . . . . . 1 - Alcohols . . . . . . . . . 1 methyl . about alcohol de- 1 '0% 1 tected : ally1 ' , alcohol I - - -~ - ~ B. Charcoal Burner's Beechwood Tar I Bohemian Tar from from Austria. , Pine Tar. Cfudbrangdalen. I 7.2% strongly acid - ! - I I creosote ' - guaiacol not deter- 1 10.5% mined - 45% I of these 46.0/,/ - about 20x aliphatic, I 80%aro- , matic - I 1 0 q 1 - 1.4% - I -- - I - , - creosote about 7'5% - - -- - - ._ The author's object was to ascertain the actual composition of the tars, not what substances could be obtained from them. Care was therefore taken to protect them as far as possible from the action of heat, air, and light. The tar was distilled under reduced pressure, the distillate being divided into two portions-light and heavy wood oil.From each portion some aqueous solution separated. In that which separated from the light oil acetone was determined by conversion into iodoform and weighing. The iodoform obtainable from the other aqueous solution was similarly determined, and the aldehydes and ketones in the oils were estimated by known methods. The acetic acid was determined by titrating another portion of the first aqueous liquid with standard caustic soda. The phenols and the fatty acids were extracted from the different fractions by appropriate treat- ment with various bases. After the aldehydes, ketones, fatty acids, snd phenols had been removed, the hydrocarbons and other neutral bodies remaining were washed with water and weighed. The esters were determined in these by saponification with alcoholic potash, evaporating, dissolving in water, acidifying, and weighing the acids precipitated.The creosote was apparently determined by fractional distillation at atmospheric pressure, the portion coming over between 200" and 220" C . being collected and weighed. A. M.THE ANALYST. 129 On the Use of Millon’s Reagent. 0. Nasse. (PJiiger’s Archiv, 1901, lxxxiii., 361-368 ; through Zeit. fiir Untersuch. der Nahr. und Genussmittel, 1902, v., 14-15.)- The author uses an aqueous solution of mercuric acetate instead of mercuric nitrate, adding a few drops of a 1 per cent. solution of sodium or potassium nitrite. The solution is usually sufficiently acid in itself, but a little dilute acetic acid may be added if necessary. The presence of nitric acid is unnecessary, and the action is to be considered a nitroso-reaction rather than a nitration.The reaction is retarded by hydrogen peroxide, by the presence of too much chloride, and by alcohol, which latter, however, can be added after cooling without influence. With the simple hydroxylated benzene derivatives, and those in which only one hydrogen atom has been substituted, the reagent as prepared by the author gives different colorations, The ortho compounds yield a brown-red colour, the para compounds blue-red to blue, and the meta compounds various tints. Albuminous bodies and their decomposition products, tyrosin, and the derivatives of p-cresol give the blue-violet para reaction. Almost all phenols and salicylic acid give the para reaction. The conversion of ortho into para oxybeneoic acid by fusion with potassium hydroxide can be shown by the reagent, the former being coloured red-brown, and the latter blue-red. The phenol-aldehyde reaction has been recommended by Denigh (Compt. Rsndu, 1900, cxxx., 583) for the detection of tyrosin, and the author finds that when this body is gently warmed with 2 to 3 c.c of a mixture of concentrated sulphuric acid with a few drops of formaldehyde, the solution is coloured red-brown, which changes to green on the addition of glacial acetic acid. The three hydroxybenzoic acids give a similar red-brown colour, but these are not turned green by glacial acetic acid. w. P. s.