AXALPTICAL CHEMISTRY. 91 A n a l y t i c a1 C h e m i s t r y. Contributions to Volumetric Analysis. By G. FL E u R Y (J. Pharm. Chiwz., xxvi, 329).-E’stimatior~ of Sulphuric Acid.-A moditi- cation of Boutron and Boudet’s hydrotimetric method for the estimation of sulphuric acid in water. The author recommends a greater dilution of the barium nitrate solution, and the expulsion of all the carbonic acid by the addition of hydrochloric acid arid boiling. The whole process is given in det’ail. Zstimation of Magnesia.- After precipitation of the lime in the usual way, the excess of ammonium oxalate is destroyed by boiling with sul- phuric acid ; ammonia, ammonium chloride, and a known quantity of sodium phosphate are added (in such quantity that there shall be at least 0.1 gram phosphoric acid in excess), and the liquid is made up t o a known volume, and left for twelve hours.Yrom 20 to 30 C.C. of the clear solution (containing 0.1 gram €€,PO,) are then titrated with uranium nitrate, with the precautions recommended by Joulie. c. w. w. Use of Bromine in Gas Analysis. By 31. BERTHELOT (Ann. Clzirn. Phys. [5], xii, 297-302). The gas is collected over water in a graduated tube of 15-20 cb.c. capacity provided with a cork through which a capillary tube passes. A small tube containing not more than half a cb.c. of bromine is brought into the graduated cylinder, and the cork with the capillary tube is inserted. The apparatus is now held in a slanting position and gently shaken, in order to bring the bromine vapour in contact with the gas.After the bromine vapour has filled the cylinder, the cork is removed, allowiiig the liquid bromine in the small tube to escape. The bromine vapour is absorbed by solid caustic potash, and the volume of residual gas measured. w. c. w. Estimation of Gases dissolved in Water. By 1’ E L I x B R L LAM Y (J. Pharm. Chim., xxvi, 324-329) -The author finds it advantageous, in cases where the determination of the gases cannot be immediately performed, to add to the water a small quantity of one of the follow- ing solutions :-(1) 8 or 10 C.C. of a saturated solution of alum and 8-5 C.C. of ammonia per litre of water; (2) 5 C.C. of a 6 per cent. solution of aluminium sulphate (as alum) with 3-5 C.C. of ammonia per litre of water; (3) 5 C.C. of an 8-10 per cent. solution of zinc sulphate with 3-5 C.C.of ammonia per litre of water. Ammonia alone produces the same effect, though not so thorouglily. The action of these solutions probably depends upon the precipitated92 ABSTRACTS OF CHEMICAL PAPERS. alumina or zinc hydrate rendering insoluble the organic matter present in the water. The action of ammonia alone is not so easily explained. A series of tables is given, showing the action of these solutions in preventing the loss of oxygen on standing. The author draws the following conclusions from these tables :- (1) If water containing organic matter be kept in corked flasks, the oxygen disappears gradually and completely, the carbonic acid at the same time increasing. (2) In water to which alum and ammonia have been added the oxygen remains the same, even after eighteen days’ Standing, whilst in natural water, after eleven daya, the oxygen had diminished by more then half.c. w. w. On the Detemjnation of Cuprous Oxide present in Copper. By C. RAMMELSBERG (Deut. Chem. Ces. Rer., x, 1780--1781).-By digesting cuprous oxide with a solution of silver nitrate in excess, in addition to metallic silver, an insoluble basic copper nitrate is formed. The author has determined the empirical constitution of this salt to be CuloN,0z6. The reaction by which it is formed appears to be the fol- lowing :- At the same time it is probable that the composition of the basic nitrate mag vary with the conditions of its formation. The reaction in ques- tio; canGot, therefore, be employed for the estimation of cuprous oxide.C. F. C. Note on the Estimation of Mineral Poisons. By N. SOKO- LOFF (BUZZ. Soc. Chim. [2], xxviii, 348).-The author states that the organic constituents of a dead body are never completely decomposed by the methods of oxidation usually practised. To attain this end, and therefore to ensure the complete isolation of mineral poisons, the transparent liquid mass obtahed by treating the intestines with hydro- chloric acid and potassium chlorate is evaporated to dryness, and the residue heated to redness in a crucible, with addition of a small quantity of potassium nitrate in place of chlorate. The author has employed this method for the estimation of zinc, copper, and lead, in cases i f poisoning by compoundtJ of these metals. c. E. c. Presence of Ammonia in Tartrates.By E. HOLDERMANN (Arch. Pharm. [IS], xi, 44--46).-The author had occasion to prepare a Fehling’s solution, and observed the smell of ammonia on dissolving the tartrate in a, hot solution of caustic soda. Analysis showed that the sample, although approved by the German pharmacopoeia, and manufactured by a well known chemical firm, contained ammonia to the extent of 0.355 per cent., present ai6 chloride. The author con- cludes from this that a chemical preparation may correspond with all that the pharmacopmia requires, but may at the same time contain sub- stances which render its use for analytical purposes quite impossible.ANALYTICAL OHEMI8TRY. 93 In this case, for instance, the presence of ammonia greatly influenced the success of the reaction of Fehling's solution on sugar. By K.CALM B E 1~ G (Arch. Pharm. [ 31, xi, 47).-The author mentions that in Buchner's Repert, 1876, 11 and 12, a process is described which has been reprinted from the Jahresbe?-icht des Phys. Vereirzs, Frankfort-on-the-Maine, 1874-75. It is stated that by diluting 10 C.C. of genuine red wine with 90 C.C. of distilled water, and adding 10 C.C. of a concentrated solution of sulphate of copper, a scarcely visible greenish coloration is obtained, whereas wine prepared with mallows shows within a few minutes a pure blue to bluish-violet colour. The author states that this is not correct, and that the same result is obtained in both cases. D. B. D. B. Testing of Red Wine. Examination of Wine as to the Presence of Glycerin, Colouring Matter, 6 % ~ .By E. REICIIARDT (Arch. Phccrw,. [3], xi, 142-152). In these investigations the following points were deter- mined :-(1.) The spec@ gravity. This varied from 0.99 t o 1.02, with the exception of champagne, which has a density of 1.042. (2.) The percentage: of acid. This is referred to a monobasic acid calculated as tartaric acid. ( 3 . ) Alcohol; residue on, evaporation; ash. 200 grams or 200 C.C. were distilled until two-thirds of the volume had come over. The alcohol was determined in the distillate in the usual manner, while the residue in the retort was evaporated at 100" and weighed until constant in weight. Thus the residue on evaporation was obtained, while after igniting the former the ash remained. (4.) Glycerin. The vr-ine or a certain portion of the evaporated residue was evaporated with an excess of slaked lime, and the residue treated several times with 90 per cent.alcohol. In the case of pure wine, perfectly pure colourless glycerin remains ; the same is the case with red wines. Gallised wines, however, yield partly gelatinous, partly turbid solid residues, which have to be separated once more by a mixture of alcohol and ether. Glycerin is deposited in this solvent, while the foreign constituents remain in the residue. (5.) CoZouring matter of red wine. Gautier's method again proved to be the best and most certain test for investigating wines as to their colouring matter (Arch. Pharm., 486). The author then proceeds to give a full account of the various analyses of wines, the results of which may be tabulated as follows :- Quality.Nierst. Kranzb., 1875.. .. Nackenheimer, 1874. . . . . Xierst. Brudersb., 1874 (Aulese) ... .. .. .. .. .. Michelsb. Aulese, 1874. . . Rauenthaler, lS'74., . . . . . Nierst. Rehbach, 1874 . . . Hochheimer Berg., 1870. . Grafenberger, 1868 . . . . . . Acid. Alcohol. Extract. Ash. Glycerine. sp*gr-i I 1 i I 0 -994 0 -993 0 -993 9 -990 0 *096 0 *095 0 -993 1 '000 0 *410 0 -420 0.533 0.495 0.683 0 -580 0 -713 0 *517 9 96 8 %3 9 '90 11 so0 8 $3 9 -69 9 -90 9 -90 2 -794 2 '536 2 '268 2.500 3.020 4 '195 2 *6i:<0 4 -390 0 -260 0 -216 0 -288 3 -188 0 '210 0 '250 0.214 0 -190 1 '326 0 -978 1.368 1 -158 1 *I96 1 '4.98 0 978 1 '66494 ABSTRACTS OF CHEMICAL PAPERS. St. Est?phe, 18'74 ....... Csutaiiec, 1874. ......... Gr.Moulis, 18'75.. ...... Quality. 0.99'7 0 0995 0.995 French Red Wines. 2.250 1.950 3.850 2'230 0.230 0.543 0-262 0.322: 0.180 0'540 0'275 0.436 0 -600 0 '600 0 *600 0.600 White wine, 18'71 ....... Ditt,o, 1874 (with root sugar) ............... Ditto, 1874 (with starch sugsr) ............... Red wine, 1875 ......... 9-00 2.9'76 0.280 1'035 lE::i 1 2.608 I 0-236 1 1.408 8.63 2.534 0.216 1.102 2 *380 0.240 0+871+ 0 '994 0.998 1 -006 0.999 French White Wines. Barsac, 1869.. .......... 1.020 0'430 10.50 5.020 0.410 1.537 Sauternes, 1865. ....... .I 0 -996 1 0'592 1 10 -88 I 3 -700 1 0 '295 1 1 '150 Auction Wines. Red wine .............. 0.992 0.980 9.65 2.376 0.190 0.620" Champagne ............ 1 1 *042 1 0 .GOO 1 12 *OO I 15 '246 I 0 1 0.090t Jema Wines. 0 *507 0 '615 0 '473 0 %OO 7 '88 5 *25 6 '57 4 -20 Frnn lcfurt Ap f E lwe in .18'75 ................ ..I 1.000 1 0'483 I 4*40 1 2.413 I 0.394 I 0.744 ~~ The above comparison shows that the more northern wine rcgions of Germany produce a much smaller quantity of glycerin, and that the presence of the latter determines the origin of wines. Although it seems probable that now aBd then a certain relation exists between alcohol and glycerin, or between residue and glycerin, it is nevertheless impossible to obtain certain data for comparison. With regard to good, strong, unadulterated Rhine wines and Bordeaux wines, the quantity of glycerin should be from 1 to 1.5 per cent. By treating the evaporated residues of unadulterated wines with lime and alcohol, pure glycerin is obtained. By treating winos gal- lised with starch-sugar in a similar manner a mixture of glycerin and a body resembling dextrin is obtained.This body is no doubt iden- tical with that observed by Neubauer. It may be separated by a mix- ture of ether and alcohol. With regard to the optical properties of this body, some differences were always noticed. By exsmiiiiiig wines directly as to the polarisation, they often showed different re- sults, more especially the above wine, which polarised distinctly to the left. Although these optical investigations have yet to be followed up further, they are likely to promise useful results. D. B. * Also 0.650 per cent, solid, similar to clextrin. + Also 0190 per cent. solid, similar to dextrin. 2 Also 0.100 per cent. solid, similar to dextrin.TECHNICAL CHEMISTRY.9 5 The Estimation of Casein and Fat in Milk. By J. L EHMANN (Liebig's 9wn(rZen, clxxxix, 358--367).-Five grams of milk diluted with an equal weight of distilled water are allowed to flow slowly from a pipette on to a porous earthenware plate standing over sulphu- ric acid, but covered with a clock-glass to prevent the evaporation of the milk. The pores of the plate must be so small as not to admit the passage of tlie smallest milk-globule, the diameter of which is 0.001 to 0.025 millimeter. I n two hours the serum of the milk will be absorbed by tlie plate, leaving behind the casein and fat. This residue is removed by the aid of a sharp horn spatula, dried for two hours at 10,5", and weighed. The fat is dissolved out in the usual way with ether, the residue, consisting of casein and mineral matter, is weighed, then ignited, and the weight of ash deducted from the weight of caseiii and ash.This method gives good results ; the fat determinations agree with those made by the ordinmy process of evaporating to dryness and extracting with ether ; but the amount of casein is higher than t h a t which Hoppe-Seyler obtains by precipitating with acetic acid. The great drawback to the process is the difficulty of obtaining plates possessing the requisite degree of porosity. w. C.W.AXALPTICAL CHEMISTRY. 91A n a l y t i c a1 C h e m i s t r y.Contributions to Volumetric Analysis. By G. FL E u R Y (J.Pharm. Chiwz., xxvi, 329).-E’stimatior~ of Sulphuric Acid.-A moditi-cation of Boutron and Boudet’s hydrotimetric method for theestimation of sulphuric acid in water.The author recommends agreater dilution of the barium nitrate solution, and the expulsion ofall the carbonic acid by the addition of hydrochloric acid arid boiling.The whole process is given in det’ail.Zstimation of Magnesia.- After precipitation of the lime in the usualway, the excess of ammonium oxalate is destroyed by boiling with sul-phuric acid ; ammonia, ammonium chloride, and a known quantity ofsodium phosphate are added (in such quantity that there shall be atleast 0.1 gram phosphoric acid in excess), and the liquid is made up t oa known volume, and left for twelve hours.Yrom 20 to 30 C.C. of the clear solution (containing 0.1 gram€€,PO,) are then titrated with uranium nitrate, with the precautionsrecommended by Joulie.c. w. w.Use of Bromine in Gas Analysis. By 31. BERTHELOT (Ann.Clzirn. Phys. [5], xii, 297-302). The gas is collected over waterin a graduated tube of 15-20 cb.c. capacity provided with a corkthrough which a capillary tube passes. A small tube containingnot more than half a cb.c. of bromine is brought into the graduatedcylinder, and the cork with the capillary tube is inserted. Theapparatus is now held in a slanting position and gently shaken, inorder to bring the bromine vapour in contact with the gas. After thebromine vapour has filled the cylinder, the cork is removed, allowiiigthe liquid bromine in the small tube to escape. The bromine vapouris absorbed by solid caustic potash, and the volume of residual gasmeasured.w. c. w.Estimation of Gases dissolved in Water. By 1’ E L I x B R L LAM Y(J. Pharm. Chim., xxvi, 324-329) -The author finds it advantageous,in cases where the determination of the gases cannot be immediatelyperformed, to add to the water a small quantity of one of the follow-ing solutions :-(1) 8 or 10 C.C. of a saturated solution of alum and8-5 C.C. of ammonia per litre of water; (2) 5 C.C. of a 6 per cent.solution of aluminium sulphate (as alum) with 3-5 C.C. of ammoniaper litre of water; (3) 5 C.C. of an 8-10 per cent. solution of zincsulphate with 3-5 C.C. of ammonia per litre of water. Ammoniaalone produces the same effect, though not so thorouglily.The action of these solutions probably depends upon the precipitate92 ABSTRACTS OF CHEMICAL PAPERS.alumina or zinc hydrate rendering insoluble the organic matter presentin the water.The action of ammonia alone is not so easily explained.A series of tables is given, showing the action of these solutions inpreventing the loss of oxygen on standing. The author draws thefollowing conclusions from these tables :-(1) If water containing organic matter be kept in corked flasks, theoxygen disappears gradually and completely, the carbonic acid at thesame time increasing.(2) In water to which alum and ammonia have been added theoxygen remains the same, even after eighteen days’ Standing, whilst innatural water, after eleven daya, the oxygen had diminished by morethen half. c.w. w.On the Detemjnation of Cuprous Oxide present in Copper.By C. RAMMELSBERG (Deut. Chem. Ces. Rer., x, 1780--1781).-Bydigesting cuprous oxide with a solution of silver nitrate in excess, inaddition to metallic silver, an insoluble basic copper nitrate is formed.The author has determined the empirical constitution of this salt to beCuloN,0z6. The reaction by which it is formed appears to be the fol-lowing :-At the same time it is probable that the composition of the basic nitratemag vary with the conditions of its formation. The reaction in ques-tio; canGot, therefore, be employed for the estimation of cuprous oxide.C. F. C.Note on the Estimation of Mineral Poisons. By N. SOKO-LOFF (BUZZ. Soc. Chim. [2], xxviii, 348).-The author states that theorganic constituents of a dead body are never completely decomposedby the methods of oxidation usually practised.To attain this end,and therefore to ensure the complete isolation of mineral poisons, thetransparent liquid mass obtahed by treating the intestines with hydro-chloric acid and potassium chlorate is evaporated to dryness, and theresidue heated to redness in a crucible, with addition of a smallquantity of potassium nitrate in place of chlorate.The author has employed this method for the estimation of zinc,copper, and lead, in cases i f poisoning by compoundtJ of these metals. c. E. c.Presence of Ammonia in Tartrates. By E. HOLDERMANN(Arch. Pharm. [IS], xi, 44--46).-The author had occasion to preparea Fehling’s solution, and observed the smell of ammonia on dissolvingthe tartrate in a, hot solution of caustic soda.Analysis showed thatthe sample, although approved by the German pharmacopoeia, andmanufactured by a well known chemical firm, contained ammonia tothe extent of 0.355 per cent., present ai6 chloride. The author con-cludes from this that a chemical preparation may correspond with allthat the pharmacopmia requires, but may at the same time contain sub-stances which render its use for analytical purposes quite impossibleANALYTICAL OHEMI8TRY. 93In this case, for instance, the presence of ammonia greatly influencedthe success of the reaction of Fehling's solution on sugar.By K. CALM B E 1~ G (Arch. Pharm. [ 31, xi,47).-The author mentions that in Buchner's Repert, 1876, 11 and 12,a process is described which has been reprinted from the Jahresbe?-ichtdes Phys.Vereirzs, Frankfort-on-the-Maine, 1874-75. It is stated thatby diluting 10 C.C. of genuine red wine with 90 C.C. of distilled water,and adding 10 C.C. of a concentrated solution of sulphate of copper, ascarcely visible greenish coloration is obtained, whereas wine preparedwith mallows shows within a few minutes a pure blue to bluish-violetcolour. The author states that this is not correct, and that the sameresult is obtained in both cases. D. B.D. B.Testing of Red Wine.Examination of Wine as to the Presence of Glycerin,Colouring Matter, 6 % ~ . By E. REICIIARDT (Arch. Phccrw,. [3], xi,142-152). In these investigations the following points were deter-mined :-(1.) The spec@ gravity.This varied from 0.99 t o 1.02, withthe exception of champagne, which has a density of 1.042. (2.) Thepercentage: of acid. This is referred to a monobasic acid calculatedas tartaric acid. ( 3 . ) Alcohol; residue on, evaporation; ash. 200grams or 200 C.C. were distilled until two-thirds of the volume hadcome over. The alcohol was determined in the distillate in the usualmanner, while the residue in the retort was evaporated at 100" andweighed until constant in weight. Thus the residue on evaporationwas obtained, while after igniting the former the ash remained.(4.) Glycerin. The vr-ine or a certain portion of the evaporatedresidue was evaporated with an excess of slaked lime, and the residuetreated several times with 90 per cent.alcohol. In the case of purewine, perfectly pure colourless glycerin remains ; the same is the casewith red wines. Gallised wines, however, yield partly gelatinous,partly turbid solid residues, which have to be separated once more bya mixture of alcohol and ether. Glycerin is deposited in this solvent,while the foreign constituents remain in the residue. (5.) CoZouringmatter of red wine. Gautier's method again proved to be the best andmost certain test for investigating wines as to their colouring matter(Arch. Pharm., 486).The author then proceeds to give a full account of the variousanalyses of wines, the results of which may be tabulated as follows :-Quality.Nierst. Kranzb., 1875.. ..Nackenheimer, 1874.. . . .Xierst. Brudersb., 1874(Aulese) ... .. .. .. .. ..Michelsb. Aulese, 1874. . .Rauenthaler, lS'74., . . . . .Nierst. Rehbach, 1874 . . .Hochheimer Berg., 1870. .Grafenberger, 1868 . . . . . .Acid. Alcohol. Extract. Ash. Glycerine. sp*gr-i I 1 i I0 -9940 -9930 -9939 -9900 *0960 *0950 -9931 '0000 *4100 -4200.5330.4950.6830 -5800 -7130 *5179 968 %39 '9011 so08 $39 -699 -909 -902 -7942 '5362 '2682.5003.0204 '1952 *6i:<04 -3900 -2600 -2160 -2883 -1880 '2100 '2500.2140 -1901 '3260 -9781.3681 -1581 *I961 '4.980 9781 '6694 ABSTRACTS OF CHEMICAL PAPERS.St. Est?phe, 18'74 .......Csutaiiec, 1874. .........Gr. Moulis, 18'75.. ......Quality.0.99'70 09950.995French Red Wines.2.2501.9503.8502'2300.230 0.5430-262 0.322:0.180 0'5400'275 0.4360 -6000 '6000 *6000.600White wine, 18'71 .......Ditt,o, 1874 (with rootsugar) ...............Ditto, 1874 (with starchsugsr) ...............Red wine, 1875 .........9-00 2.9'76 0.280 1'035lE::i 1 2.608 I 0-236 1 1.4088.63 2.534 0.216 1.1022 *380 0.240 0+871+0 '9940.9981 -0060.999French White Wines.Barsac, 1869............ 1.020 0'430 10.50 5.020 0.410 1.537Sauternes, 1865. ....... .I 0 -996 1 0'592 1 10 -88 I 3 -700 1 0 '295 1 1 '150Auction Wines.Red wine .............. 0.992 0.980 9.65 2.376 0.190 0.620"Champagne ............ 1 1 *042 1 0 .GOO 1 12 *OO I 15 '246 I 0 1 0.090tJema Wines.0 *5070 '6150 '4730 %OO7 '885 *256 '574 -20Frnn lcfurt Ap f E lwe in .18'75 ................ ..I 1.000 1 0'483 I 4*40 1 2.413 I 0.394 I 0.744~~The above comparison shows that the more northern wine rcgions ofGermany produce a much smaller quantity of glycerin, and that thepresence of the latter determines the origin of wines.Although itseems probable that now aBd then a certain relation exists betweenalcohol and glycerin, or between residue and glycerin, it is neverthelessimpossible to obtain certain data for comparison. With regard to good,strong, unadulterated Rhine wines and Bordeaux wines, the quantityof glycerin should be from 1 to 1.5 per cent.By treating the evaporated residues of unadulterated wines withlime and alcohol, pure glycerin is obtained.By treating winos gal-lised with starch-sugar in a similar manner a mixture of glycerin anda body resembling dextrin is obtained. This body is no doubt iden-tical with that observed by Neubauer. It may be separated by a mix-ture of ether and alcohol. With regard to the optical properties ofthis body, some differences were always noticed. By exsmiiiiiigwines directly as to the polarisation, they often showed different re-sults, more especially the above wine, which polarised distinctly to theleft. Although these optical investigations have yet to be followed upfurther, they are likely to promise useful results. D. B.* Also 0.650 per cent, solid, similar to clextrin. + Also 0190 per cent. solid, similar to dextrin.2 Also 0.100 per cent. solid, similar to dextrinTECHNICAL CHEMISTRY. 9 5The Estimation of Casein and Fat in Milk. By J. L EHMANN(Liebig's 9wn(rZen, clxxxix, 358--367).-Five grams of milk dilutedwith an equal weight of distilled water are allowed to flow slowlyfrom a pipette on to a porous earthenware plate standing over sulphu-ric acid, but covered with a clock-glass to prevent the evaporation ofthe milk. The pores of the plate must be so small as not to admit thepassage of tlie smallest milk-globule, the diameter of which is 0.001to 0.025 millimeter. I n two hours the serum of the milk will beabsorbed by tlie plate, leaving behind the casein and fat. This residueis removed by the aid of a sharp horn spatula, dried for two hoursat 10,5", and weighed. The fat is dissolved out in the usual way withether, the residue, consisting of casein and mineral matter, is weighed,then ignited, and the weight of ash deducted from the weight of caseiiiand ash.This method gives good results ; the fat determinations agree withthose made by the ordinmy process of evaporating to dryness andextracting with ether ; but the amount of casein is higher than t h a twhich Hoppe-Seyler obtains by precipitating with acetic acid. Thegreat drawback to the process is the difficulty of obtaining platespossessing the requisite degree of porosity. w. C.W