THE ANALYSTI 265 ORGANIC ANALYSIS. Analysis of Sugar Mixtures. C. A. Browne. (Jozwn. Amer. Chem. Soc., 1906, xxviii., 439-453.)-Since the weights of two different sugars reducing the same amount of copper bear a constant ratio to one another, the differences in the reducing powers of the various sugars can be very simply expressed by determining this ratio for each sugar, compared with dextrose as a standard. These constants are termed the ‘‘ dextrose ratios ” or “ equivalents,” and based on the conclusions that (1) the266 THE ANALYST. dextrose equivalent of a mixture of reducing sugars is equal to the sum of the dextrose equivalents of the individual sugars (which the author has proved, notwith- standing statements to the contrary); and (2) the polarization of a, mixture of sugars is equal to the sum of the polarizations of the individual sugars present, formulae are developed which enable the percentage composition of a mixture of any two sugars, or of three sugars, one of which is sucrose, to be ascertained from determina- tions of the copper-reducing power of the mixture and of its polarization.Two sources of error arise in such separations, due to (1) the slight reducing action of sucrose upon Fehling’s solution, and (2) the change in rotation of laevulose in neutral and acid solution. I n some experiments with a mixture of dextrose and sucrose, the error due to the first-mentioned cause is found to be inversely proportional to the amount of dextrose present, and the following correction gives concordant results : Divide the grams of sucrose in the 25 C.C.of solution to be analysed by Allihn’s method by the mgms. of dextrose found +40, and subtract the quotient in grams from the dextrose found. The correction for the second source of error depends upon the concentration of the acid used for inversion and the dilution of the sugar solution; for 10 C.C. fuming HCl (specific gravity 1.18) and 100 C.C. of sugar solution the correction is 0,036 per cent. for each percentage of IEvulose. Experi- ments on a number of known mixtures of various sugars have proved the accuracy of the method. W: H. S. On the Colour Reactions of Sesame Oil. P. Soltsien. (Cham. Rev. Fett. a. Haw-Ind., 1906, xiii., 138.) - Further experiments have confirmed the author’s conclusion that the furfural reaction and the tin reaction of sesame oil are not due to one and the same substance.Both compounds can be extracted by shaking the oil with alcohol of 90 per cent. strength, but thorough extraction with hydrochloric acid of specific gravity 1-125 removes the substance that gives the furfural reaction, whilst the oil still gives the tin reaction as strongly as before. The tin react,ion is also quite independent of Bishop’s reaction. Hence, if a sesame oil for any reason gives neither the furfural nor Bishop’s reaction, it may still be possible to identify it by the tin reaction (see ANALYST, xxvii., 363 ; xxviii., 298, 364). C. A. M. On Indian Ghedda Wax. Georg Buchrer. ( C h m Zeit., 1906, xxx., 528.) -The author takes exception to the statement of Dr. J. Konig ( ‘ I Die Untersuchung landwirtschaftlich und gewerblich wichtiger Stoffe,” ed.1906, p. 939), that the Ghedda wax of India is not to be regarded as real beeswax. The matter is of importance, since for church use only candles made from beeswax may be used. Ghedda wax is produced by three species of bees, two of which-Apis dorsata and ApZs fZorea -stand evolutionally directly before the European ApZs meZZi$ca, whilst the third-Apis indica or fasciata-appears to be a variety of Apis meZli$ca. Ghedda wax is qualitatively of the same composition as ordinary beeswax, but differs from it quantitatively, the amount of free cerotic acid being very much less and theTHE ANALYST. 267 This is shown in the quantity of esters very much higher in the Indian wax. following table : Source .___--.~__ Apis dorsata .. . . (23 samples) Apis Jlorea . . . (5 samples) . . . Apis indica ... (7 samples) Apis mellifica . . . Average Maximum Minimum Average Maximum Minimum Average Maximum Minimum Average Maximum Minimum 63.1 67.0 60.0 64.2 68.0 63-0 63.25 64-0 62.0 63.25 7-0 10-2 4.4 7.5 8-9 6.1 6.8 8.8 5-0 20.0 -- 96.2 105.0 75-6 103.2 130-5 88.5 96.2 102.5 90.0 95.0 todine Value (Hiibl). --- 6.7 9-9 4.8 8.0 11.4 6.6 7.4 9.2 5.3 7.5 11.0 4.0 The author is of opinion that Ghedda wax is to be regarded as a true beeswax, and as such admissible for church use. A. G. L. The Reaction of Mercuric Acetate with Camphene and Pinene. L. Bal- biano. (Reale Accad. d i Lincei; through Phzarm. Journ., 1906, vol. 76, p. 641.)- When equal volumes of benzene and an essential oil containing camphene are shaken with a 25 per cent.solution of mercuric acetate, and allowed to stand for thirty days, a crystalline compound, CloHl,0(HgC2H,0,),, is formed which is insoluble in water, alcohol, and ether. When the crystals are suspended in water and treated with a current of hydrogen sulphide they regenerate camphene. When pinene is subjected to prolonged contact with aqueous mercuric acetate solution, the reaction is quite diff'erent, A6 oxymenthenone being formed. w. P. s. A New Method for the Determination of Nitrogen in Nitrocellulose. M. Busch. (Chem. Ztg., 1906, xxx., 596.)-The nitrocellulose is saponified with caustic alkali in the presence of hydrogen peroxide, which prevents reduction of the nitrate by the cellulose further than to nitrite.On acidifying in the presence of hydrogen peroxide, the nitrite is also quantitatively oxidized to nitrate. The determination is then completed by adding (' nitiron,'' and weighing the nitron nitrate (C,oH,,N,~HNO,). A. G. L. Extraction of Tanning Materials for Analysis. F. P. Veitch and H. H. Hurt. (Journ. Anzer. Chem. Soc., 1906, xxviii., 505-512.)-Further experiments with the continuous extractor confirm the conclusion that this extractor gives the most complete extraction, all soluble constituents being removed by it in larger quantities than by other extractors. It has been stated that with sumac and canaigre268 THE ANALYST. the temperature must be kept at from 50" to 60' C. until at least half the volume of the extract is obtained ; but these materials were extracted satisfactorily in the con- tinuous extractor with from 200 to 300 C.C.of water below 100' C., the extraction being completed at steam heat. All materials should be ground to pass at most a millimetre sieve, and extraction should be continued for at least sixteen hours, pre- ferably for twenty-four hours. W. H. S. Strychnine Tannate and its Application to the Analysis of Tanning Materials. S. R. Trotman and J. E. Hackford. (Leclerrnarkt, CoZZegium, 1906, 69 ; through Chenz. Zeit., 1906, xxx., Rep. 167.)-The tannate of strychnine is almost insoluble in water, whilst the gallic acid compound is easily soluble. In making an analysis, the tanning material is extracted with alcohol. The extract, which should contain about 0.5 gram of active substance, is evaporated to 50 c.c., and made up to 100 C.C.with water. The liquid is filtered from the resinous bodies, and 25 C.C. of the filtrate are diluted with water, after which 0.25 gram of strychnine dissolved in 50 C.C. of alcohol and 50 C.C. of water is added, and the whole diluted to 250 C.C. with water. The precipitate is filtered off on to a Gooch crucible and dried in vacuo. Experiments with pure tannin showed that if an excess of strychnine is present, the tannate contains 1 molecule of strychnine for every 1 molecule of tannic acid. A. G. L. The Determination of Uric Acid in Urine. G. Guerin. (Jouwz. Pharnz. Cham., 1906, xxiii., 516, 517.)-One gram of anhydrous sodium carbonate is dissolved in 120 to 125 of the urine and the resulting precipitate of phosphates separated by filtration.One hundred C.C. of the filtrate are mixed with 25 C.C. of a solution of ammonium nitrate (50 grams in 100 c.c.), followed by 5 C.C. of ammonia solution, and allowed to stand until the next day, when the uric acid will have been quantitatively precipitated 8;s ammonium urate. The precipitate is collected, washed with a solution containing 10 per cent. of ammonium nitrate and 1 per cent, of ammonia, and transferred with the aid of a jet of water into an Erlenmeyer flask. The turbid liquid (about 100 c.c.) is mixed with 40 C.C. of sulphuric acid (1 : l), heated to 50° C., and titrated with a standard solution of potassium permanganate (1.5 gram per litre), the flask being shaken after each addition. The number of C.C.consumed multiplied by 0.00356 gives the amount of uric acid in 100 C.C. of the urine, The method is directly applicable to urines containing albumin. Urines that give a deposit of urate ought to be slightly heated on the water-bath and shaken until the sediment dissolves, before the addition of the sodium carbonate. C. A. M. Estimation of Ammonia in Used Lime Liquors. H. R. Procter and D. McCandlish. (JozLT?~. XOC. Chem. h d . , 1906, xxv., 254256.)--A current of air, freed from carbon dioxide and ammonia by passage through U-tubes filled with NaOH and H,SO,, is rapidly drawn, by means of a water-pump, through the ammoniacal liquor contained in a ' 6 glass worm " immersed in a water-bath at 90" C., and thence through a U-tube containing a known volume of standard acid.Frothing is obviated, and the time required reduced from one hour to thirty minutes byTHE ANALYST. 269 replacing the " glass worm " by the following apparatus : A piece of glass tubing, A (about &-inch bore), is drawn out to a fine point at one end, which is bent up as shown in the figure. Over this point is fixed, by wiring round a piece of cork, a second tube, B, of the same diameter as A, but slightly widened at the end. The tubes are then fitted in a wide test-tube (10 inches by 2 inches) containing sufficient water to cover their junction, the long arm of A passing through a two-holed rubber stopper, FIG. 1. and being connected with U-tubes containing NaOH and H,SO, for purifying the air. Through the other hole of the stopper is a short piece of bent glass tubing making connection with a U-tube containing 30 to 40 C.C.of & acid, which in turn is attached to the pump. The tubes A and B are so adjusted that the passage of the air came8 a continuous stream of water up to B, air also escaping from the bottom of B and rising outside it. The test-tube is filled with broken glass up to within 2 inches of its top, and over the end of B ip, placed the inverted head of a thistle funnel, the aperture where the stem was connected having been carefully sealed. The tube is then placed in a water-bath at 90" C., 50 C.C. of the lime liquor introduced into A through a filter funnel, and slight suction applied, whereby the liquor is continuously raised to the top of B and thrown back by the thistle funnel upon the broken glass, whence it runs.back to the bottom of the tube, the ammonia being thus completely drawn off within thirty minutes. W. H. S. Notes on the Determination of Ash in Elementary Organio Analysis, (Chem. Ztg., 1906, xxx., 567.)-The author finds that in Fritz von Konek.270 THE ANALYST. analysing coals the amount of ash left in the carbon and hydrogen determination (carried out in an electrically-heated furnace) is always higher than that given by the usual method of ashing the sample in a platinum crucible in the air. He shows that platinum boats increase in weight (up to 0.8 mgm.) on ignition in oxygen, coming back to their original weight on prolonged heating in air. Many substances (calcium carbonate, iron oxides, etc.) also behave differently according as to whether ignited in oxygen or air. Finally, the quantity taken for the elementary analysis is so small that it is very difficult to obtain a fair sample as regards ash. For all these reasons the author prefers to take the usual ash figure obtained by burning 1 or 2 grams of the fuel in a crucible. A. G. L. Combustion of Halogen Compounds in Presence of Copper Oxide. C. J. Robinson. (Amer. Chem. Journ., 1906, vol. 35, pp. 531-533.)-The need for a separate combustion tube filled with lead chromate is obviated by placing just in front of the boat in the ordinary combustion tube a cartridge of heavy copper wire gauze rolled into the form of a hollow cylinder, 6 or 7. em. long, and filled with pure lead chromate, the ends being closed by wrapping with Cu wire, which, passing also lengthwise through the cartridge, is looped at each end to facilitate removal from the tube. The arrangement has given good results for the determination of C, H, and N in halogen compounds, and would probably also be suitable .for the estimation of C and H in sulphur compounds. W. H. S'