摘要:

INDEX TO VOLUME XXIV. ABBA F. Bacterial detection of Arsenic 51 ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS 6 33 73 88 127 148 184, Acetanilide Vanillin mixed with 16 Acetic Aldehyde Volumetric estimation of 213 Acetone New method of detecting and estimating 92 - in Urine Detection of 155 Acetyl value Meaning of the in Fat analysis 319 Acetylene Detection of in cases of Poisoning therewith 11 Acid Benzoic Detection of synthetic [Toluene] in the resined sublimed product 286 - Boric Estimation of 139 - -I Influence of on Digestive Enzymes 103 - - Tests for 904 - - in Milk Detection of 145 - Chromic Reduction of by Acetic Acid and its effect in ilnthracene testing 186 - Elaidic Iodine value of 258 - Gallic Influence of on the estimation of Tannins 160 - Glycero-phosphoric Notes on 216 - Hydrocyanic Note on the estimation of by Liebig’s method 163 - Linolic Detection and quantitative estimation of 134 - Nitric Detection of free in Toxicological work 11 - Nitrous reaction in a drinking Water False 27 - Oleic Acetyl value of 322 __- Separation of 132 - Oxalic in Urine Estimation of 249 - Phosphoric Estimation of I ‘ available,” in Thomas Slag 25 - Picric 46 -_ Salicylic Hydrogen peroxide as a test for 287 - Selenious Influence of Hydrochloric Acid in titrating with Sodium thiosulphate, with special reference to the determination of 193: - Silico-Tungstic Use of as a reagent for Alkaloids 187 205 237 259 283 331 and Isovaleric Acids Method for the quantitative separation of 114 Oil Composition and analysis of 214 Notes on 291 samples Note on 141 - - -7 Tannin and Pyrogallol Reaction of 137 - -- solutions Stability of 249 I 1 total in Thomas meal 251 __ - Influence of on Digestive Enzymes 10 iv INDEX TO VOLUME XXIV, Acid Suiphuric Estimation of in presence of Iron 164 - 1 - -1 - Uric Estimation of 164 - - Modification of Deniges’ method of estimating 189 - Violet 4BN 47 - Yellow 47 Acidimetry New Indication for 166 Acids Chloric Bromic and Iodic Some reactions of 165 - - Estimation of from the volume of Hydrogen evolved on treatment with -.Fatty Determination of the Iodine value of 245 -- - of Cotton-seed Oil Action of Silver nitrate on the 247 - Isovaleric and Acetic Method for the quantitative separation of 114 - and Alkalies Volumetric estimation of by means of Iodine 80 Acridines 44 Act Sale of Food and Drugs of 1899 309 Adam F.Volumetric estimation of Alcohols especially of Fusel Oil in Brandy 259 Agar-Agar Pentosaus in 182 Aikman C. M. Milk its Nature and Composition 2nd edition Review 278 Air Detection and estimation of Mercury vapour in 251 Albumin in Urine Test for 102 Albuminous substances in Urine Determination of 289 Albumoses from Peptones Separation of 49 Alcohol Allyl iodine value of 258 -_ Ethyl Detection of Methyl Alcohol in 13 211 - Methyl Simple colour reaction for 212 -_ 1- in commercial Spirits Detection of 212 - - in Ethyl Alcohol Detection of 13 211 _I- Vinyl Colour reaction for 267 -_ and Ether Estimation of in the presence of Petroleum Ether 201 -_ other Organic bodies Flash-point of dilute 131 _I__- in Tinctura Lobelie [Xtherea] Estimation of 154 Alcohols Volumetric estimation of especially of Fusel Oil in Brandy 259 - Wool Wax Acetyl value of 321 Aldehyde Acetic Volumetric estimation of 213 - Gravimetric 137 -1 1 - 1 - combined Volumetric 25 .Solubility of Methane and Ethane in fuming 154 -metals 304 -_ 1 - Separation of Unsaturated from one another 132 -_ 7 in Butter Volatile and insoluble 7 Use of Persulphates to detect 49 Ethyl Preparation of a standard solution of 37 Formic Detection of in Food stuffs 151 Alizarin 45 - Red 45 - Yellow A 45 Alkali Violet 47 Alkalies and Acids Volumetric estimation of by means of Iodine 80 Alkaloids Emetine octo-iodide and the extraction and estimation of generally 74 Piutti’s reagent for (Iodine derivative of p-Ethoxyphenylsuccinimide) 11 Use of Silico-Tungstic Acid as a reagent for 187 Allen A.H. Coffee Extracts 282 - Commercial Organic Analysis 3rd edition Review 167 - Composition of Bread 232 II- Ginger 12 INDEX TO VOLUME XXIV. V Ally1 Alcohol Iodine value of 258 Alpers W. C. Characteristics of the Oil and Terpenes of A r a b Nudicaulis 294 Aluminium Separation of Zinc Copper Mercury or Bismuth from 17 - and Iron Separation of by volatilizing the Ferric chloride 301 Ammonia Nitrates and Nitrites in Water Determination of 221 Ammonium citrate solution Method of preparing an exactly neutral 25 - Magnesium phosphate of analysis Constitution of the 192 - sulphide Polysulphides in Copper as a reagent for 111 Analysis Advantage of using L( Normal Volunies ” in 27 Andreasch F.Silician Sumach and its adulterants 49 Andrlik - Estimation of Pentoses in presence of Saccharose 157 Aniline Volumetric estimation of 245 Anschiitz Frofessor R. Editor Organic Chemistry ; or the Chemistry of the Carbon Anthracene testing Reduction of Chromic Acid by Acetic Acid and its effect in 186 Anthraquinones 45 Antiseptics in Food 140 Antony U. aizd Lucchesi A Determination of total Sulphur in Coal 272 Apparatus Some new 223 APPARATUS. Apples Zinc in dried 8 Aralia Nudicaulis Characteristics of the Oil and Terpenes of 294 Araliene 294 Archbutt L. Acetyl value in Fat analysis 328 Arrowroot Pentosans in 182 Arsenic Bacterial detection of 51 - in Glycerin Determination of 181 Aschmann C. Estimation of total Phosphoric Acid in Thomas meal 251 - and Faber H.Estimation of Humus in Soil 103 Asphalt Determination of Sulphur in 48 Atlas of Bacteriology (Slater and Spitta). Beview 55 Atomic Weights for analytical purposes List of 82 Buchy G. Determination of Tungsten in Steel 164 Auramines 44 Aurantia 43 Surins 45 Austin M. and Gooch F. A, Constitution of the Ammonium Magnesium phosphate of analysis 192 Avery S. and Dales B. Notes on the electrolytic determination of Iron 79 Am-Blue 43 --colour Testing for Yellow in Fats etc. 73 Bacteria Influence of on the decay of Cement 251 Bacteriology Atlas of (Slater and Spitta) Review 55 Balsams and Resins 6ome recent methods of examining 77 Banana Flour Composition of 150 Barium compounds in Artesian Well Water Occurrence of 67 -_ salts in Cayenne Pepper Presence of 207 Bark Sassafras Composition of 90 Test for Albumin in Urine 102 compounds 3rd edition Review 279 ABSTRACTS 27 54 84 111 139,194 222 252 276 307 - ores Modification of Pierce’s method for the determination of 298 - industrial purposes 222 Note on Drown’s method of determining Silicon in Steel 53 Estimation of ;Molybdenum as phosphate 5 vi INDEX TO VOLUME XXIV.Barralet E. So Delicate reaction of Hydrogen peroxide 194 Barth G.,. Influence of Bacteria on the decay of Cement 251 Basic Slag (Thomas meal) Valuation of on the basis of its percentage of soluble Bassett H. Reduction of Chromic Acid by Acetic Acid and its effect in dnthracene Bastien T. Detection of Horseflesh in Sausages 73 Baucher F.Adulteration of Scarnmony with Galena and Starch 241 Baudouin reaction 246 Bauer - Solanine in Potatoes and a sensitive reaction for its detection 152 Baum F. Apparatus for the extraction of Liquids with Ether 196 Baumann K. Detection of Maize Starch in Wheat meal 150 Baumert G. and Falke F. Alteration in the character of Butter produced by feeding Beam. See Leffmann-Beam Beer Cider Wine and Urine Estimation of Chlorides in 49 - Malt and Wort Estimation of the Nitrogenous constituents of 184 Bees' Wax Acetyl value of 321 Bein S. Occurrence of a Ptomaine in Coffee 36 Bek F. Estimation of Sinapine 153 Bell E. W. Estimation of Potash 192 Belladonna leavee Assay of 241 -Bellier J. Detection and estimation of Earthnut Oil in other Oils 98 Bennett J.F. Modification of Pierce's method for the determination of Arsenic in Benzidine and Tolidine Reaction for 290 Benzoic Acid Detection of synthetical [Toluene] in the resin sublimed product 286 Benzophenones 45 Benzoyl compounds Colour reaction of the 268 Berberine 239 Bergamot Oil of Estimation of 50 BertB C. and Soldaini A. Estimation of Oil of Bergamot 50 Bertrand G. Use of Silico-Tungstic Acid as a reagent for Alkaloids 187 Bevan E. J. Dyer B. nizd Hehner O. Recent Ginger case 169 Biebrich Scarlet,'47 Bile Pigments in Urine Detection axid estimation of 249 Binz A, and Rung F. Estimation of Indigo on Fabrics 48 Bird F. C. J. Assay of Belladonna Plaster 175 Bismarck Brown 43 Bismuth Volumetric determination of 220 - Zinc Copper or Mercury from Aluminium Separation of 17 Blanc.See Le Blanc Blank O. and Finkenbeiner H. Estimation of Formaldehyde 92 Blast New form of Water 54 Blattner N. and Brasseur J . Estimation of Perchlorate in Saltpetre 26 Blood Microscopic identification of 210 - Notes on the Guaiacum reaction for the detection of 266 -- of different animals Haematin of the 162 Blue Azo- 43 - Fluorescent 44 - Methylene 43 Phosphoric Acid 305 testing 186 with Fat 6 - Humble- 39 and some of its preparations Away of 208 - Plaster Assay of 175 Ores 29 INDEX TO VOLUME XXIV. vii Blue Nile A. 43 Bodmer R Leonard N. and Smith H. M. Analysis of Golden Syrup 253 Bolm F. Determination of Potassium as Potassium Platinum Chloride 274 Bomer A, False Nitrous Acid reaction in a drinking Water 27 BOOKS REVIEWS OF: process for detecting Cotton-Oil Stearin in Lard Notes on the 149 Aikman C.M. Milk its Nature and Composition 2nd edition 278 Allen A. H. Commercial Organic Analysis 3rd edition 167 Anschutz Professor R. Edztor Organic Chemistry ; or the Chemistry of the Clowes F. Treatise on Practical Chemistry and Qualitative Analysis, Erdmann Professor Dr. H. Anleitung zur Darstellung Chemischer Prii-Leffmann H. Edztor Commercial Organic Analysis 3rd edition 167 Moor C G. and Pearmain T. H. Chemical and Biological analysis of Richter. See Von Richter Slater C. and Spitta,-E. J. Atlas of Bacteriology 55 Von Richter V. Organic Chemistry ; or the Chemistry of the Carbon Com-Whipple G. C. Microscopy of drinking Water 166 Carbon Compounds 3rd edition 279 7th edition 308 parate 2nd edition 224 Water 166 pounds 3rd edition 279 Bordeaux B.43 . s. 47 Boric Acid Estimation of 139 - 7- Influence of on Digestive Enzymes 103 - Tests for 304 - in Milk Detection of 145 samples Note on 141 Borntrager H. Analysis of Silicon 276 Bourcet P. Detection and estimation of traces of Iodine in Organic substances 271 Bourquelot E. and Herissey H. Estimation of Mannose in the presence of other Brandt L. Impure I r o n a possible source of error in Nitrogen estimations by Brandy Volumetric determination of Fuse1 Oil in 259 Breads Some comparative analyses of and digestion experiments with white and Brearley H Estimation of Molybdenurp 18 Breteau P. and Cazeneuve P. Composition and reactions of Solanine 216 Braukeleveen.See Van Breukeleveen Brilliant Congo 47 -- Yellow 47 Bromic Chloric and Iodic Acids Some reactions of 165 Bromination test for Oils Heat of 97 Bromoform Detection and estimation of in toxicological work 210 Brown Bismarck 43 Brucine and Strychnine Separafe estimation of 75 Bruhns’ improved Polarimeter 252 Budde C. C. and Schou C. V. Electrolytic method of determining Nitrogen in Buisine il. and P. Composition and analysis of Acetone Oil 214 Sugars 288 the Ulsch method 80 whole-meal 227 - Haematin of the Blood of different animals 162 Congo 46 Organic substances 27 viii INDEX TO VOLUME XXIV. Bunsen Professor R. Pi. Death of 226 Burette Automatic 2 Burettes Automatic 4 Butter Alteration in the character of produced by feeding with Fat 6 - Cacao Acetyl value of 327 Composition of 200 .- Detection of renovated 88 - Fatty Acids in Volatile and insoluble 7 - Microscopy of 206 - Water in Proportion of 148 Cacao Butter Acetyl value of 327 Caesium and Rubidium Separation of 110 Cafe Marron 284 Caffeine Qornberg’s method for estimating compared with other methods 152 Campbell L. D. a d Champion E. C. Electrolytic estimation of Tin in Tin ores 108 Cane-Sugar in hlilk Detection of 144 Caoutchouc Milk Examination of 78 Capsaicin 263 Caramel Estimation of 13 Carbazol 47 Carbon and Hydrogen in Organic substances containing Nitrogen Determination by - volatile Organic liquids Apparatus for the estimation of 139 - in Iron Estimation of by combustion 22 Carmine Indigo 44 Carnauba Wax Acetyl value of 321 Carpiaux E.aizd Grkgoire A. Estimation of Pentoses 39 Cttseril C. E. Coffee extrdets 282 Caator 014 Acetyl value of 327 Cavalier J. aizd Pouget - Notes on Glycero-phosphoric Acid 216 Cayenne Pepper Active principle of 263 -- Presence of Barium salts in 207 Cazeneuve P. and Breteau P Composition and reactions of Solanine 216 Cazeneuve’s method of detecting artificial Colour in Wines Notes on 89 Cellulose in Gun-Cotton Determination of unaltered 217 Cement Influence of Bacteria on the decay of 251 Ceresiu New lnethod of examining used by the German customs 270 - and Paraffin Determination of the dropping-point of 269 Cerium from Lanthanum and ‘‘ Didymium,” Separation of 110 Cevadine 209 Champion E. C. and Campbell E. D. Electrolytic estimation of Tin in Tin ores 108 Chandelon T.Copper as a reagent for Polysulphides in Ammonium sulphide 111 -- Tetrathionates in Sodium thiosulphate 111 Chapman A. C. Bread 234 . - Wine Saccharine Liquids etc. Detection of 34 in Spirits and Vinegar Detection of 207 combustion of 290 -- Hematin of the Blood of different animals 162 -- Method for the quantitative separation of Isovaleric and Acetic Charabot E. and March -- Action of Silver nitrate on the Fatty Acids of Cotton-Acids 114 seed Qil. 247 -__ - Pillet L. Characteristics of Essence of Neroli and Essence of Petit-grain 100 - INDEX TO VOLUME XXIV. 1x Charabot E. and Pillet L. Composition of Essence of Petit-grain 156 Chattaway W. Ginger adulteration 171 Cheese Ripening of Alteration of Milk-Fat in the 149 Chemischer Praparate Anleitung zur Darstellung (Erdmann) 2nd edition Revzew, Chervil Essential Oil of Occurrence of Estragol in the 244 Chicory Composition and analysis of 261 - Pentosans in 180 Chloric Broniic and Iodic Acids Some reactions of 165 Chlorides in Urine Wine Beer and Cider Estimation of 49 Chlorine compounds in Cotton Oil and its behaviour with the Phloroglucinol and Cholesterin and Phytosterin Melzer’s colonr-reaction as a test for 76 Chrome Yellow Analysis of commercial 19 Chromic Acid Reduction of by Acetic Acid and its effect in Anthracene testing 186 Chromium oxide in Algerian Phosphates Determination of 52 Chrysamine 43 Cider Wine Beer and Urine Estimation of Chlorides in 49 Cinnamon Ash of certain descriptions of 154 Citrel and Citronellal Method of separating 99 Clayton E.G. Note on Boric Acid in Milk samples 141 - Some analyses of Ginger 122 Clowes F. Treatise on Practical Chemistry and Qualitative Analysis 7th edition, Coal Calorific power of Calculation of from analytical data 107 - Sulphur in Determination of total 272 Coburn Dr. L. Hopkins E. und Spiller E. Analysis of Dkgras or Sod Oil 160 Cocaine New test for 237 Coccine New 47 Cochineal 47 Cochran C. B. Detection of renovated Butter 88 Cocoa Analyses of 181 - Pentosans of 180 -_ nut Oil Acetyl value of 325 Cod liver Oil Acetyl value of 327 Coffee Glazed 36 - Pentosans in 180 - Ptomaine in Occurrence of a 36 - Studies on new descriptions of 1 ; Bourbon Coffee (Cafk Marron) 284 -_- extracts their composition and analysis 281 Cognac Oil of 184 Colophony Composition of 294 Colour in Wines Notes on Cazeneuve’s method of detecting artificial 89 Colouring matters Method of analysing natural and artificial 41 Comboni E.Notes on Cazeneuve’s method of detecting artificial Colour in LYjiies 89 Commercial Organic Analysis (Allen edited by Leffmann) 3rd edition Rsviezu 167 Condenser for Extraction work 140 Occurrence of Estragol in the Essential Oil of Chervil, 244 1 - Changes which take place in Ifilk-Fat during the 34 224 Vanillin test 332 Review 308 Oil 97 - Contributions to our knowledge of 136 - Notes ou 77 use with Beakers Reflux 22 X IKDEX TO VOLUME XXIV. Congo Brilliant 47 - Red 43 Consistency of Grease and similar articles Apparatus for determining the 28 Cook A.D. Method of preparing an exactly neutral Ammonium citrate solution 25 Copper Mercury Bismuth or Zinc from Aluminium Separation of 17 Corn Oil 97 Cotton-cake Composition of decorticated 182 Brown 46 Oil Chlorine compounds in and its behaviour with the Phloroglucinol and - Stearin ((( Vegetal ”) in Lard Detection of by means of the Phytosferiu Notes on the Bomer process 149 __- Acetyl value of 322 327 __- Action of Silver nitrate on the Fatty Acids of 247 - Halphen reaction for 214 Vanillin test 332 test. - seed Oil 97 99 Question of the retention of Phytosterin in the animal system on Feeding with 283 Yellow R 47 Coumarin and Vanillin Separation and identification of 162 Cow’s Milk Influence of Distillery refuse on 148 Crampton C.A, und Simons F. D. Detection of Caramel in Spirits and Vinegar 207 Cream Composition of 200 Creosote Examination of Wood-Tar 292 Croton Oil Characteristics of 285 Cuniasse L. Colour reaction distinguishing Metaphenylenediamine hydrochloride Curcas Oil Acetyl value of 327 __.- Characteristics of 14 Dales B. and Avery S. Notes on the electrolytic determination of Iron 79 Daw F. W. Estimation of Manganese by means of Potassium permanganate 110 De Koningh L. Notes on Milk analysis 142 De Negri G. Oil of Paradise Nuts Oil of Brazil Nuts Maize Oil 15 De Paepe D. Calculation of the Calorific power of Coal from analytical data 107 Dkgras or Sod Oil Analysis of 160 Denigks G. Colour reaction of the Benzoyl compounds 268 - Determination of Albuminous substances in Urine 289 - New method of detecting and estimating Acetone 92 - Reactions of some common Phenols 38 DenigBs’ method of estimating Uric Acid Modification of 189 Dennis L.M. uizd Hopkins C. G. Combustion of mixed Gases containing Carbon Dewalque F. Determination of added Starch in pressed Yeast 89 Diamond Yellow 43 ( I Didymium ” and Lanthanum Separation of Cerium from 110 Dieterich K. Some recent methods for examining Balsams and Resins 77 Dietz R. a d Xylius I?. Qualitative separation of the Platinum metals 108 Digestion Reactions distinguishing the products of Peptic and Pancreatic 272 Digestive Enzymes Influence of Food Preservatives on 102 Dionine 128 Dioxine 43 from Paraphenylenediamine hydrochloride 245 monoxide Methane and Hydrogen 104 - R 47 Distillation in high vacua Apparatus for 112 - .. . INDEX TO VOLUME XXIV. xi Distillery refuse Influence of on Cow’s Milk 148 Dohler E. Separation of Nickel and Zinc 191 Dorse Oil Constants of 136 Dowzard E. Estimation of Alcohol in Tinctura Lobeliae [Btherea] 154 Drink and Food Detection of Saccharin in articles of 152 Drown’s method of determining Silicon in Steel Note on 53 Duchemin R. Notes on Acetone Oil 291 Ducommun J. Reaction of metallic Sulphides soluble in Ammonium sulphide 22 Dulidre W. Characteristics of Croton Oil 285 Dupouy R. Oxy-Ferments of Milk and Saliva 79 Dyer Dr. B. Address to the Society of Public Analysts 59 - Estimation of Fat in Milk 174 - Ginger 126 - Origin of Barium compounds in Artesian Well Water 71 -- Bevan E.J. and Hehner O. Recent Ginger case 169 Earthnut Oil 95 Eckardt M. and Le Blanc >I. Titration of Persulphates 165 Ehrlich E. Action of Formaldehyde on Flesh 8 Eichloff R. Determination of Dirt in Milk 33 Ekroos H. Valuation of Phosphorated Oil 91 Elaidic Acid Iodine value of 258 Ellms J. W. Study of the relative value of Lacmoid Phenacetolin and Erythrosin as Indicators in the determination of the Hardness of Water by Hehner’s method, 194 Einetine octo-iodide and the extraction and estimation of Alkaloids generally 74 Enzymes Influence of Food Preservatives on Digestive 102 Eosin 45 Erdmann H. Atomic Weights for industrial purposes 222 Professor Dr. H. Anleiturig zur Darstellung Chemischer Priiparate 2nd edition Review 224 Ergot in Mea! Detection and estimation of 265 Erlwein G.and Weyl T. Recognition of Ozone in presence of Nitrous Acid and Erythrosin 46 Erythrosin Lacmoid and Phenacetolin Study of the relative value of as Indicahrs Essence of Neroli and Essence of Petit-grain Characteristics of 100 Ess’ential Oil of Chervil Occurrence of Estragol in the 244 Estcourt C. Caper Tea 30 Estragol Occurrence of in the Essential Oil of Chervil 244 Ethane and Methane Solubility of in fuming Sulphuric Acid 154 Ether Purity of used a$ a Fat solvent 94 - and Alcohol Estimation of in the presence of Petroleum Ether 201 - extraction Incandescent electric lamp as a source of heat in 308 Ethoxyphenylsuccinimide Iodine-derivative of (Piutti’s reagent for Alkaloids) 11 Ethyl Alcohol Detection and estimation of Methyl Alcohol in 13 - Aldehyde Preparation of a saturated solution of 37 Eucalyptol Notes on estimating 10 Evers F.Methods for distinguishing between raw Linseed and boiled Oil 158 Extract of Ipecacuanha Assay of liquid 128 in other Oils Detection and estimation of 98 Hydrogen peroxide 82 in the determination of the Hardness of Water by Hehner’s method 194 - Petit-grain Composition of 156 9 of Methyl Alcohol in 21 .xii ,INDEX TO VOLUME XXIV. Extraction of Liquids with Ether Apparatus for the 196 -__-____ immiscible solvents Apparatus for the repeated 27 Extracts Coffee their composition and analysis 281 ‘‘ Extractum Hydrastis Fluidurn,’’ Estimation of Hydrastine in 9 Eynon L. and Streatfield F. W. Apparatus for the estimation of Carbon and Hydrogen in volatile Organic Liquids 139 Faber H and Aschmann C.Estimation of Humus in Soil 103 Fahrion W. Constants of various Train Oils 135 Falke F. and Baumert G. Alterations in the character of Butter produced by Farnsteiner K. Contribution to our knowledge of Wine Vinegar 151 Fat Nilk- Alteration of in the ripening of Cheese 149 -_ - Changes which take place in during the ripening of Cheese 34 - analysis Meaning of the Acetyl value in 319 - in Glue Estimation of 248 -__ Milk Areometric determination of 205 - Estimation of using Petroleum Ether as a solvent 172 - Note on a possible source of error in modifications of the Leffmann-Beam Fats Comparison of the methods of Iodine absorption in the Analysis of 94 - Relative digestibility of certain Food in the human alimentary canal 237 - and Oils Detection and Estimation of free Phosphorus in 287 - etc.Testing for a Yellow Azo-colour in 73 Fatty Acids Determination of the Iodine value of 245 - in Butter Volatile and insoluble 7 - of Cotton-seed Oil Action of Silver nitrate on the 247 Feeding stuffs and Foods Determination of digestible Nitrogenous matter and - with Cotton-seed Oil Question of the retention of Phytosterin in the animal Feld W. Estimation of Sulphides Sulphites and Thiosulphates 23 Fennel seed Examination and characteristics of commercial 127 Ferments Oxy- of Milk and of Saliva 79 Ferric chloride and Phenol Reaction between in presence of Alcohol 38 - solutions Use of Potassium ferrocyanide for preparing for volumetric purposes, Ferro-Tungsten Analysis of 18 Fessel a71.d Kunkel Mm.Detection and estimation of hlercury vapour in air 251 Fibre Furcora gigantea a new commercial 220 Filiti G. Determination of Sulphur in Russian Petroleum 272 Filter-pump accessory 194 Filtrations Apparatus for increasing the speed of 55 Finkenbeiner H. ant1 Blank D, Estimation of Formaldehyde 92 Finkener - Determination of the dropping-point of Ceresin and Paraffin 269 Fish Oil Constants of Japan 136 Fish Oils Constants of various 135 - Saponification value of 186 - work Condenser for 140 - Estimation of Fat in Glue 248 - Saponification value of Fish Oils 186 Feeding with Fat 6 - Separation of unsaturated Fatty Acids from one another 132 method for the estimation of 146 - Separation of unsaturated from one another 132 albutninoid Nitrogen in 263 system on 283 - Fat Alteration in the character of Butter produced by 6 30 INDEX TO VOLUME XXIV.xiii Fisher W. W. Food and Drugs legislation 317 --_ Formaldehyde 86 -. Ginger adulteration 171 Flash-point of dilute Alcohol and other Organic bodies 131 Flateau J. altd LabbB H. Method of separating Citronella1 and Citral 99 Flavones 45 Flesh Action of Formaldehyde on 8 Flour Composition of Banana 150 Fluorescent Blue 44 Fluorine in Wine Detection of 285 Foerster 0 Estimation of Perchlorate in Chili Saltpetre 26 Food Antiseptics in 140 -_ and Drink Detection of Saccharin in articles of 152 - Preservatives Influence of on Digestive Enzymes 102 - Substances and Gums Estimation of Gelatin i n 35 Foods Analysis of Estimation of Pentoses and its application to the 178 FOODS AND DRUGS ANALYSIS.ABSTRACTS 6 33 73 88 127 148,184 205,237,269, Foods and Feeding Stuffs Determination of digestible Nitrogenous matter and Formaldehyde Action of on Flesh 8 --_ Estimation of 92 --. Test for New 86 -. in Food Stuffs Detection of 151 Fradiss - Estimation of Caramel 13 Frangois M. Volumetric estimation of Aniline 245 Frankforter G. B. and Pease L. B. Analysis of conimercial Veratrine 209 Frankland Sir E. Death of 225 Freundlich J. Estimation of (‘ available ” Phosphoric Acid in Thoinas Slag 25 Friedrichs F. Automatic RIercury Pump 224 Fruit Amount of Zinc in German dried 8 Fuchaine 44 Fulton C. H. Assay of Telluride Gold ores 17 Funnels for use with Filter-plates 223 Furcora gigantea a new commercial Fibre 220 Furfural Formation of from Starch and its derivatives 157 Fuse1 Oil in Brandy Volumetric determination of 259 Gallic Acid Influence of on the estimation of Tannins 160 Gamboge Adulterated 37 Gas Analysis of Illuminating 187 - washing apparatus 195 Gases Combustion of mixed containing Carbon monoxide Methane and Hydrogen, - dissolved in Water Apparatus for measuring the 195 Geerligs.See Prinsen-Geerligs Geisler J. F. Paraffin as an adulterant of Oleomargarine 284 .- - Sugar in Molasses 149 - Gas washing apparatus 195 - Drugs Act of 189Y Sale of 309 - . Stuffs Detection of Formaldehyde in 151 283 331 Albuminoid Nitrogen in 263 - Testing Note on 92 s 44 - Tannin and Pyrogallol Reaction of 137 10 XiV INDEX TO VOLUME XXIV.Gelatin in Gums and Food substances Estimation of 35 Geranial 99 German Silver and similar alloys Volumetric estimation of Nickel and Zinc in 301 Gill A. H. a?zd Hatch J. Heat of Bromination test for Oils 97 Gillespie I>. N. H. aizd Walker C. F. Volumetric estimation of Blkalies and Acids by means of Iodine 80 Gillet and Hairs Nm, Reaction for Ketones 268 Ginger Some analyses of 122 Girard and Lindet Mm. Examination of Caoutchouc Milk 78 Glass Soda unsuitable for Chemical apparatus 63 Glucose Estimation of 102 Glue Estimation of Fat in 248 Glycerin Determination of Arsenic in 131 Glycero-phosphoric Acid Notes on 216 Gockel H. Automatic reservoir Pipette 112 Gold Determination of and its separation from Platinum and Iridium 301 - and Platinum Iodometric estiniation of 108 - ores Assay of Telluride 17 - samples Valuation of 299 Golden Syrup Analysis of 253 Gomberg's method for estimating Caffeine compared with other methods 152 Gooch F.A. aizd Austin M. Constitution of the Ammonium Magnesiuni phosphate -- - Havens F. S. Separation of Iron and Aluminium by volatilizing - Jones L. C. Estimation of Boric Acid 139 - ~ - - - Morton J. T. Volumetric estimation of Molybdenum 53 Gordin H. M. aizd Prescott A. B. Emetine octo-iodide and the extraction aud - - Lamb A. C. Analytical constants of American Linseed Oil 97 case Recent 169 - Some new apparatus 223 - Water-seal for use when boiling Liquids in a reducing atmosphere 276 of analysis 192 - Estimation of Manganese as phosphate 52 the Ferric chloride 301 estimation of Alkaloids generally 74 Estimation of Morphine in Opium 265 Hyilrastine periodide and the assay of Hydrastis Canadensis 238 __-____ Separate estimation of Strychnine and Bru-cine 75 Volumetric assay of Opium 8 ---Graebe C.hpparatus for the employment of Sulphuretted Hydrogen 111 Grains of Paradise Oil of 16 Grease and similar articles Apparatus for determining the consistency of 28 Green Naphthol 43 Grhgoire A. and Carpiaux E. Estimation of Pentoses 39 Griggi G. Reaction of Gallic Acid Tannin and Pyrogallol 137 Guaiacum reaction for the detection of Blood Notes on the 266 Gums and Food substances Estimation of Gelatin in 35 Gun-cotton Determination of unaltered Cellulose in 217 Haddock Oil Saponification number of 186 Hamatin of the Blood of different animals 162 Hairs and Gillet Mm.Reaction for Ketones 268 Halphen reaction for Cotton-seed Oil 21 INDEX TO VOLUME XXITr. xv Hanausek E. Glazed Coffee 36 T. F. Studies on new descriptions of Coffee 1 ; Bourbon Coffee (Cafir Hanus J. Hazel-nut Oil 291 Harlay V. Reactions distinguishing between t,he products of Peptic and Pancreatic Hartleb R. and Stutzer A, Estimation of Calcium Carbonate in Soil 275 ~-- Influence of Bacteria on the decay of Cement 251 Hasterlik A. Detection of Saccharin in articles of Food and Drink 152 Hatch J. and Gill A. H. Heat of Bromination test for Oils 97 Havens F. S, Separation of Zinc Copper Mercury or Bismuth from Aluminium 17 - and Gooch F. A, Separation of Iron and Aluminium by volatilizing Hazel-nut Oil 291 Hefelmann R.Vanillin mixed with Acotanilide 16 Hehner O. Acetyl value in Fat analysis 328 Marron) 284 Digestion 272 the Ferric chloride 301 Breads 233 and Skertchly W P. Estimation of Pentosans and its applications to the analysis of Foods 178 - Bevan E. J. and Dyer B. Recent Ginger case 169 Heidenreich 0. N. Determination of Sulphur in Iron Pyrites 193 Heinemann A, Estimation of Tannins and the influence of Gallic Acid on the Renriques R. Analysis of Indiarubber articles 297 process 160 Composition of Colophony 294 Volatile and insoluble Fatty Acids in Butter 7 and Kuhne H. Characteristics of Oleo distearin 185 Henriques' process for the aualysis of Indiarubber articles 16 Herissey H. and Bourquelot E. Estimation of Mannose in the presence of other Heroine Colour-reactions of 91 Herring Oil Constants of 136 Herzfeld - Influence of Temperature on the optical determination of Sugar 157 Herzog A, Furcora gigantea a new commercial Fibre 220 Hess W.H. and Prescott A. B. Separation and identification of Coumarin and Hesse L. Dionine 128 Heupel A, Valuation of Resin 136 Hiepe - Curcas Oil 14 Hintz E. and Weber W. Analysis of Incandescent Mantles 20 Hirsh A React'ions between Iron Salts and Pyrogallol 164 Hodgson E. H. Determination of Sulphur in Asphalt 48 Hoerting O. Estimation of Sulphuric Acid in presence of Iron. Holde D. New method of examining Ceresin used by the German customs 270 and Pelgry R. Ilalphen reaction for Cotton-seed Oil 214. Holdschmidt W. Valuation of Indigo 218 Hopkins C.G. Condenser for Extraction work 140 308 Monoxide Methane and Hydrogen 104 Sugars 288 Vanillin 162 Determination of Pyrrhotite in Pyrites 164 - Incandescent Electric lamp as a source of heat in Ether extraction, -- and Dennis L. M. Combustion of mixed Gases containing Carbon Horseflesh in Sausages Detection of 73 E. Coburn D. L. and Spiller E. Analysis of DQgras or Sod Oil 16 xvi INDEX TO VOLUME XXIV. Howe J. L. and Morrison J. L. Action of a hard Water on certain metals 306 Hoyer E. Soda Glass unsuitable for chemical apparatus 83 Humble-Bees’ Wax 39 Humus in Soil Estimation of 103 Hydrastine in ‘‘ Extracturn Hydrastis Fluidum,” Estimation of 9 - Periodide and the assay of Hydrastis Canadsnsis 238 Hydrazine New method of estimating 269 Hydrocyanic Scid Note on the estimation of by Liebig’s method 163 Hydrogen Sulphuretted Apparatus for the employment of 111 - and Carbon Determination by combustion of in Organic substances con-in volatile Organic liquids Apparatus for the estimation of 139 - Methane Estimation of by fractional combustion with Copper oxide, taining Nitrogen 290 ---_ Peroxide Delicate reaction of 194 -_- Valuation of 305 Hydroquinone Reactions of 38 Illuminating Gas Analysis of 187 Incandescent Mantles Analysis of 20 Indiarubber articles Analysis of 297 Indican Estimation of 248 Indicator for Acidimetry New 166 Indicators in the determination of Hardness of Water by Hehner’s method Study of Indigo Valuation of 218 - on Fabrics Estimation of 48 Indigotin 44 Indogenides 44 Indophenols 44 Indulines 43 INORGANIC ANALYSIS.ABSTRACTS 17 51 ‘79 108 137 164 190 220 251 274 298, Institute of Chemistry Pass List 56 Iodic Brornic and Chloric Acids Some reactions of 165 Iodine absorption Comparison of the methods of in the analysis of Fats 94 -- value Determination of the 257 Iodoform in aqueous fluids Detection of 37 Ionic theory Importance of the in Analytical Chemistry 137 Ipecacuanha Assay of liquid Extract of 128 Iron Carbon in Estimation of by combustion 22 - Determihation of Notes on the electrolytic 79 - Impure a possible source of error in Ulsch Nitrogen estimations 80 - Sulphur in Volumetric estimation of by means of Arsenious Acid 302 - and Aluminium Separation of by volatilizing the Ferric Chloride 301 - from Titanium Separation of 81 -- Uranium Separation of 81 - in Water Colorimetric estimation of 51 - pyrites Determination of Sulphur in 193 - Salts and Pyrogallol Reactions between 164 131 - Some applications of in quantitative analysis 81 - Henriques’ process for the 16 the relative value of Lacmoid Phenacetolin and Erythrosin as 194 Carmine 44 332 in Organic substances Detection and estimation of traces of 27 INDEX TO VOLUME XXIV.xvii Isovaleric and Acetic Acids Method for the quantitative separation of 114 Jager E. Estimation of Hydrogen and Methane by fractional combustion with Japan Fish Oil Constants of 136 -_ Saponification number of 186 Jean F. Detection of Formaldehyde in Food stuffs 151 Jedlicka J. Volumetric estimation of Nickel and Zinc in German Silver and similar Copper oxide 131 alloys 301 Jensch F.Determination of Zinc in ores containing Alumina 221 . Jervis H. Filter-pump accessory 194 Jolles A, Detection and estimation of Bile Pigments in Urine 249 Jones L. C. and Gooch F. A, Estimation of Boric Acid 139 Jorissen W. P. Stability of Oxalic Acid solutions 249 Jowett H. A. D. Assay of Preparations containing Pilocarpine 331 Juckenack A, and Sendtner R. Examination and characteristics of commercial Jung W. L. and Schumacher - Estimation of Mercury in Urine by amalgama-Kaiser H. Presence of Barium salts in Cayenne Pepper 207 Kebler L. F. Examination of Wood-Tar Creosote 292 Note on testing Formaldehyde 92 Notes on estimating Eucalyptol 10 Fennel seed 127 tion 274 Kerp W, Baudouin reaction 246 Ketones Reaction for 268 Kippenberger C.Destruction of Organic substances in Chemico-Forensic work 12 Kirsten A. Changes which take place in Milk Fat during the Ripening of Cheese 34 Kissling R. Apparatus for determining the consistency of Grease and similar Kjeidahl’s method of determining Nitrogen Note on 189 Kleber C. Composition and characteristics of Sassafras Oil 90 Klein O. Characteristics of Curcas Oil 14 Kobert R. Some colour reactions of Morphine and its derivatives 241 Koningh. See De Koningh Krafft F Determination of the molecular weight of Soaps in Alcoholic solution 247 Kreis H. Melzer’s Picrotoxin Colour reaction as a test for Cholesterin and Phy-Kuhne El. aizd Henriques R. Characteristics of Oleo-distearin 185 Kulisch P.Amount of Zinc contained in German dried Fruit 8 Kunkel and Fessel Mm. Detection and estimation of Mercury vapour in Air 251 Kuster F. W. Direct conversion of Potassium iodide and bromide into chloride 24 - Isolation and identification of Sulphonal in Forensic work 129 articles 28 tosterin 76 and Thiel A. Gravimetric estimation of Sulphuric Acid in presence of Iron. The importance of the Ionic theory in Analytical Chemistry 137 LabbB H. Composition of Oil of Lemon grass 155 - and Flateau J. Method of separating Citronella1 and Citral 99 Lacmoid Phenacetolin and Erythrosin Study of the relative value of a8 Indicators in the determination of the Hardness of Water by Hehner’s method 194 Ladd E. F. Gomberg’s method for estimating Caffeine compared with other methods, 152 Lamb A.C. and Gill A. H. Analytical constants of American Linseed Oil 97 9 Thyme 101 -xviii INDEX TO VOLUME XXIV. Langmuir A. C. Determination of Arsenic in Glycerin 131 Lanthanum and “ Didymium,” Separation of Cerium from 110 - Cotton-Oil Stearin ( ‘ I Vegetal ”) in Detection of by means of the Phytosterin Laszczynski B. V. Estimation of Nitrogenous constituents of Malt Wort and Le Blanc M. and Eckardt M. Titration of Persulphates 165 Lead acetate Use of basic in the Polarimetry of Sugar solutions 47 Leffmann H. Edito~ Commercial Organic Analysis 3rd edition Review 167 Lmd 97 test. Beer 164 Notes on the Boiner process 149 - Influence of Food Preservatives on Digestive Enzymes 102 -Beam method for the estimation of Fat in Milk Note on a possible source of error in modifications of the 146 LEGAL NOTES 120 Lemoine A.Separation of Rubidium and Cssium 110 Lemon grass Oil of Composition of 155 Lenher V. and Wells J. S. C. Tests for Boric Acid 304 Leonard N. and Smith H. M. New test for Formaldehyde 86 Lewkowitsch J. Determination of the Iodine value 257 -- Meaning of the Acetyl value in Fat analysis 319 Lextreit - Note on the estimation of Hydrocyanic Acid by Liebig’s method 163 Liebig’s method Note on the estimation of Hydrocyanic Acid by 163 Lignin Colour reaction of 78 Lindet aizd Girard Mm. Examination of Caoutchouc Milk 76 Linolic Acid Detection and quantitative estimation of 134 Linseed cake Composition of 182 -__ Acetyl value of 322 -_____ Methods for distinguishing between raw and boiled 158 Liquids Extraction of with Ether Apparatus for the 196 - Water-seal for use when boiliug in a reducing atmosphere 276 Liquorice in Wine Detection of 260 Liver Oil Constants of Brown 136 Lloyd J.W. Detection of Starch in black and white Mustard seed 35 Lobeliae Tinctura [Btherea] Estimation of Alcohol in 154 Locusts Composition of edible 265 Loubiou - Estimation of Chlorides in Urine Wine Beer and Cider 49 Louise E. Detection and estimation of free Phosphorus in Oils and Fats 267 LOW A. H. Testing for a Yellow Azo-colour in Fats etc. 73 Lowe W. F. Adulteration of Spirits of Wine with Potassium nitrate 67 Lucas M. Colorimetric estimation of Nickel 190 Lucchesi A. and Antony U. Determination of total Sulphur in Coal 272 Liihrig H. Digestibility of ( I Palmin ” in the human alimentary canal 263 Lunge G.Estimation of Sulphuric Acid in presence of Iron 164 Magnesium Ammonium phosphate of analysis Constitution of the 192 Maize Oil 15 Smith H. M. and Bodmer R. Analysis of Golden Syrup 253 oil 95 97 - Analytical constants of American 97 - Refractometer number of 159 - Saponification number of 166 - -_- - immiscible solvents Apparatus for the repeated 27 - and Weintraub E. Determination of unaltered Cellulose in Gun-cotton 217 - Acetyl value of 32 INDEX TO VOLUME XXIV. XiX Maize Starch Detection of in Wheat meal 150 Majstorovic R. and Zega A . Determination of the Iodine value of Fatty Acids 245 Mallet E. Estimation of Uric Acid 164 Malt Wort and Beer Estimation of the Nitrogenous constituents of 184 Manganese Estimation of as phosphate 52 Mannose Estimation of in the presence of other Sugars 288 Mantles Incandescent Analysis of 20 Maquenne - Estimation of Glucose 102 - and ROUX MRT.Note on Kjeldahl’s method of determining Nitrogen 189 March - and Charabot E. Action of Silver nitrate on the Fatty Acids of Cotton-seed Oil 247 Marshall A, Bread and Flour 233 -- Influence of Ammonium salts on the precipitation of Nickel by Am monia 202 Marting B. Proportion of Water in Butter 148 Martius Yellow 46 Mayer A, Estimation of Carbonates in Soil 275 McIienna A. G. Analysis of Ferro-Tungsten 18 Meal Detection and Estimation of Ergot in 265 Melckebeke. See Van Melckebeke Nelting-points Apparatus for determining 84 Melzer’s Picrotaxin Colour reaction as a test for Cholesterin and Phytosterin 76 hfengel P.Separation of Cerium from Lanthanum and hlercury Bismuth Zinc or Copper from Aluminium Separation of 17 ~ - _ in Urine Estimation of by amalgamation 274 -_ pump Automatic 224 ~- vapour in Air Detection and estimation of 251 Metallic Sulphides soluble in Ammonium sulphide Reaction of 22 Metals Action of hard Water on certain 306 Metaphenylenediamine hydrochloride Colour reaction distinguishing from Para-phenylenediamine hydrochloride 245 Methane and Ethane Solubility of in fuming Sulphuric Acid 154 - Hydrogen Estimation of by fractional combustion with Copper oxide 131 Methner T. Purity of Ether used as a Fat solvent 94 Methyl Alcohol Simple colour reaction for 21 2 -- and Zinc Remarks on the determination of as sulphide 51 by means of Potassium permanganate 110 Didymium,” 110 - in commercial Spirits Detection of 212 Ethyl Alcohol Detection and estimation of 13 of 211 Methylene Blue 43 Micko K Active principle of Cayenne Pepper 263 Milk Boric Acid in Detection of 145 - Cane Sugar in Detecfion of 144 - Caoutchouc Examination of 78 - Cow’s Influence of Distillery refuse on 148 - Dirt in Determination of 33 - Fat in Areometric determination of 205 -7 - Estimation of using Petroleum Ether as a solvent 172 - -Leffmann-Beam method for the 146 - Skim Composition of 200 - analysis Notes on 142 - - -Orange 47 -_- Note on a possible source of error in modifications of th xx INDEX TO VOLUME XXIV.Milk and Milk products Composition of 197 -- Saliva Oxy-ferments of 79 - Fat Alteration of in the ripening of Cheese 149 ~- Changes which take place in during the ripening of Cheese 34 - its Nature and Composition (Aikman) 2nd edition Review 278 - products and Milk Composition of 197 - samples Note on Boric Acid in 141 -I separator slime Composition of 201 Milks Analysis of sour 142 Mill Laboratory Ball 222 Mineral Oils Refractometer number of 159 Minozzi A.Modification of the Sprengel tube 277 MISCELLANEOUS 140 277 Moerk F. X. Assay of Belladonna leaves 241 - --_ Method for facilitating the colour comparison in the determination of and some of its preparations 208 Nitrates in Water by the Phenolsulphonic Acid meihod 222 Molasses Estimation of Sugar in 149 Molybdenum Estimation of 18 -__ -_ Volumetric 53 Mondolfo G.H. Valuation of Persulphates 303 Monhaupt M. Advantage of using ( ( Normal Volumes ” in analysis 27 Monoethylmorphine hydrochloride 128 Montemartini C. and Trasciatti D. Determination of Morphine in Opium 264 Moor C. G. and Pearmain T. H. Chemical and biological analysis of Water, Moret. See Sonnik-Moret Morphine and its derivatives Some colour reactions of 241 Review 166 -__ - Priest M. Coffee Extracts their composition and analysis 281 in opium Determination of 264 - Estimation of 265 - silico-tungstate 188 Morpurgo G. Detection of Liquorice in Wine 260 Morrison J. L. and Howe J. L. Action of a hard water on certaiu Metals 306 hliiller I?. C. G. Apparatus for measuring the Gases dissolved in Water 195 -_- P. Separation of Albumoses from Peptones 49 Mulliken S.P. and Scudder H. Simple colour reaction for Methyl Alcohol 212 Murmann E. Remarks on the determination of Zinc and Manganese as sulphide 51 Musset I?. Detection and estimation of Ergot in Meal 265 Mustard Pentosans in 180 Mutschler L. Determination of Oxygen in Water 306 Mylius F. and Dietz R. Qualitative separation of the Platinum metals 108 Naphthas Official examination of Wood- for methylation purposes 234 Naphthol Green 43 Yellow 43 Neat’s-foot Oil 97 Negri. See De Negri Neroli Essence of and Essence of Petit-grain Characteristics of 300 Neuberg C. Determination of Phenols in Urine 250 Nickel Colorimetric estimation of 190 seed Detection of Starch in black and white 35 (Orange flowers) Oil of Constitution of 155 Influence of Ammonium salts on the precipitation of by Ammonia 20 INDEX TO VOLUME XXIV.xxi Nickel and Zinc Separation of 191 Nigrosin Soluble 44 Nile Blue A 43 Nitramines 43 Nitrates in Water Method for facilitating the colour comparison in the determination - Nitrites and Ammonia in Water Determination of 221 Nitre Spirits of Adulteration of with Potassium nitrate 87 Nitric Acid Detection of free in toxicological work 11 Nitrites Nitrates and Ammonia in Water Determination of 221 Nitro-Colouring matters 43 Nitrogen Albuminoid and digestible Nitrogenous matter in Foods and Feeding Stuffs, - Note on Kjeldahl’s method of determining 189 - estimations Impure Iron a possible source of error in Ulsch 80 -_-_ in Organic substances Electrolytic method of determining 273 Nitrogenous constituents of Malt Wort and Beer Estimation of the 184 -- matter and Albuminoid Nitrogen in Foods and Feeding Stuffs Deter-Nit ro-P henols 43 Nitrous Acid reaction in a drinking Water False 27 ‘( Normal Volumes,” Advantage of using in analysis 27 Norton J.T. Influence of Hydrochloric Acid in titrating with Sodium thiosulphate, -_- and Gooch F. A. Volumetric estimation of Molybdenum 53 Nut Hazel Oil 291 Nuts Brazil Oil of 15 - Paradise Oil of 15 in German Silver and similar Copper alloys Volumetric estimation of 301 of by the Phenol-sulphuric Acid method 222 Determination of 263 mination of digestible 263 with special reference to the determination of Selenious Acid 193 O’Shaughnessy 3’. R. and Richmond H. D. Note on a possible source of error in modifications of the Leffmann-Beam method for the estimation of Fat in Milk 146 OBITUARY Bunsen Professor R.W. 226 Frankland Sir E. 225 Enocyanin 47 Oil Acetone Composition and Analysis of 214 _- - Notes on 291 - Castor Acetyl value of 327 - -- -liver Acetyl value of 327 - Corn 97 - Cotton Chlorine compounds in and its behaviour with the Phloroglucinol and - ,- Stearin (“ Vegetal ”) in Lard Detection of by means of the Phytosterin -? Cod 97 Vanillin test 332 test Notes on the Bomer process 149 - Acetyl value of 322 327 9 -seed 97 99 - -- -- -_- Halphen reaction for 214 - Croton Characteristics of 285 - Curcas Acetyl value of 327 9 Action oE Silver nitrate on the Fatty Acids of 247 Question of the retention of Phytosterin in the animal system on __ --_- __ ______-Feeding with 28 xxii INDEX TO VOLUME XXIV.Oil Curcas Characteristics of 14 - Dorse Constants of pale 136 - Earthnut 95 - - in other Oils Detection and estimation of 98 - Essential of Chervil Occurrence of Estragol in the 244 -- Fusel in Brandy Volumetric determination of 259 - Haddock Saponification number of 186 - Hazel-nut 291 - Herring Constants of 136 - Japan Fish Constants of 136 - Linseed 95 97 - ,- Acetyl value of 322 - ,- American Analytical constants of 97 - - Methods for distinguishing between raw and boiled 158 - - Refractometer number of 159 - -_ Saponification number of 186 - Liver Constants of brown 136 - Maize 15 - 9 - Acetyl. value of 325 - Neat’s-foot 97 - Olive 97 99 - Palm Acetyl value of 325 - Phosphorated Valuation of 91 - Rape Acetyl value of 322 - Rosin Refractometer number of 159 - Sardine Constants of 136 - - Saponification number of 186 - Sassafras Composition and characteristics of 90 - Seal Constants of 136 - Sesame 99 - Shark Constants of 136 - Sod or DQgras Analysis of 160 - Sperm 97 - -- Acetyl value of 321 - Stickleback Constants of 136 - Train Constants of 136 - Tunny Fish Constants of 136 - Whale Constants of 136 - - Saponification number of 186 - and Terpenes of Aralia Nudicaulis Characteristics of the 294 - of Bergamot Estimation of 50 - Brazil nuts 15 - Cognac 184 Grains of Paradise 16 - Lemon grass Composition of 155 - Neroli (Orange flowers) Constitution of 155 - Paradise nuts 15 - Sassafras keaves 90 - Thyme Composition of 101 - Turpentine Refractometer number of American 159 Oils Earthnut Oil in other Detection and estimation of 98 - - Saponification number of 186 - 7 - Saponification number of 186 7 Saponification number of 186 -_ -INDEX TO VOLUME XXIV.xxiii Oils Fish Constants of various 135 -- - Saponification value of 186 -_- Heat of Broniination test for 97 -- Mineral Refractometer number of 159 _- Train Constants of various 135 Oils and Fats Detection and estimation of free Phosphorus in 287 - Varnish Examination of with the Refractometer 158 Oleic Acid Acetyl value of 322 Oleo-distearin Characteristics of 185 Oleomargarine Paraffin as an adulterant of 284 Olive Oil 99 Opium Determination of Morphine in 264 - Estimation of Morphine in 265 Orange Methyl 47 - flowers (Neroli) Oil of Constitution of 155 Orcein 44 Organic Analysis Commercial (Allen edited by Leffmann) 3rd edition Review 167 ORGANIC ANALYSIS.ABSTRACTS 13 37 74 92 131 154 185 211 242 267 288 Organic bodies Flash-point of dilute Alcohol and other 131 ~- Chemistry ; or the Chemistry of the Carbon Compounds (Von Richter), - Colouring matters Method of analysing natural and artificial 41 liquids Apparatus for the Estimation of Carbon and Hydrogen in volatile 139 ~- substances Ash in A. E. Shuttleworth’s method of determining 271 Separation of 132 Volumetric assay of 8 G 47 3rd edition Review 279 - Destruction of in Chernico-Forensic work 12 - Iodine in Detection and estimation of traces of 271 - Nitrogen in Electrolytic method of determining 273 - containing Nitrogen Determination by combustion of Carbon and Hydrogen in 290 Orseille 47 Oven Electrically-heated Drying 307 Oxalic Acid in Urine Estimation of 249 - solutions Stability of 249 Oxazones 44 Oxygen in Water Determination of 306 Oxy-ketone Colouring matters 45 Ozone Recognition of in presence of Nitrous Acid and Hydrogen peroxide 82 Paepe.See De Paepe Palm Oil Acetyl value of 325 ( 6 Palmin,” Digestibility of in the human alimentary canal 283 Papasogli G. Detection of Cane-Sugar in Urine Saccharine Liquids etc. 34 Paraffin and Ceresin Determination of the dropping-point of 269 - as an adulterant of Oleomargarine 284 Paraphenylenediamine hydrochloride Colour reaction distinguishing Metaphenylene-Paris G.Detection of Fluorine in Wine 285 Pearmain T. H. and Moor C. G. Chemical and biological analysis of Water, Pears Zinc in dried 8 Pease L. B. and Frankforter G. B. Analysis of commeroial Veratrine 209 diamine hydrochloride from 245 Revzew 16 xxiv INDEX TO VOLUME XXIV. Pelgry R. and Holde D. Halphen reaction for Cotton-seed Oil 214 Pentosans Estimation of and its application to the analysis of Foods 178 Pentoses Estimation of 39 -_ -Pepper Cayenne Active principle of 263 - - Presence of Barium salts in 207 Peptones Separation of Albumoses from 49 Persulphates Titration of 165 -- Use of to detect Albumin in Urine 49 --_ Valuation of 303 Petermann A. Composition of Banana flour 150 -- Influence of Distillery refuse on Cow’s Milk 148 Peters F.Reaction between Ferric chloride and Phenol in presence of Alcohol 38 Petersen H. Iodometric estimation of Gold and Platinum 108 Petit-grain Essence of Composition of 156 -- and Essence of Neroli Characteristics of 100 Petroleum Determination of Sulphur in Russian 272 Pfeiffer O. Analysis of Illuminating Gas 187 Phenacetin Lacmoid and Erythrosin Study of the relative value of as Indicators in the Determination of Hardness in Water by Hehner’s method 194 Phenol and Ferric chloride Reaction between in presence of Alcohol 38 Phenols Reactions of some common 38 - in Urine Determination of 250 Phloroglucinol Reaction of 38 Phloxin B 47 Phosphates Determination of Chromium oxide in Algerian 52 Phosphine 44 Phosphorated Oil Valuation of 91 Phosphoric Acid in Thomas meal Estimation of total 251 Phosphorus in Oils and Fats Detection and estimation of free 287 Phthaleins 45 Phytosterin Question of the retention of in the animal system on Feeding with - and Cholesterin Melzer’s Colour reaction as a test for 76 - test Detection of Cotton-Oil Stertrin (“ Vegetal”) in Lard by means of the 149 Picric Acid 46 Pierce’s method for the determination of Arsenic in Ores Modification of 298 Pillet L.and Charabot E. Characteristics of Essence of Neroli and Essence of in presence of Saccharose 157 Pentosans in 180 - slag Estimation of available 25 - Phosphorus paste Rapid estimation of small quantities of free 33 Cotton-seed Oil 283 Petit-grain 100 - Coniposition of Essence of Petit-grain 156 -__-- Occurrence of Estragol in the Essential Oil of Chervil 244 Pilocarpine 331 - Assay of preparations containing 331 ~ - _ nitrate 331 Pipette Automatic reservoir 112 Piutfi A.Colour reaction of Lignin 78 Piutti’s reagent for Alkaloids (Iodine derivative of p-Ethoxyphenylsuccinimide) 11 Plaster Belladonna Assay of 175 Platinum and Gold Iodometric estimation of 108 hydrochloride 33 INDEX TO VOLUME XXIV. XXV Platinum metals Qualitative separation of the 108 Poisoning Detection of Acetylene in cases of 11 Polarimeter Bruhns' improved 252 Polarimeters Influence of temperature on the specific rotation of Sucrose and method Polarimetry of Sugars Use of basic Lead acetate in the 47 Polyaulphides in Ammonium Sulphide Copper as a reagent for 111 Ponceau 6RB 47 Posner T.Apparatus for the repeated Extraction of Liquids with immiscible solvents 27 Potash Estimation of 192 Potassium Determination of as Potassium Platinum chloride 274 - -- ferrocyanide Use of for preparing standard Ferric solutions for volumetric of correcting readings of compensating 288 purposes 303 - iodide end bromide Direct conversion of into chloride 24 - nitrate Estimation of perchlorate in 26 Potatoes Solanine in and a sensitive reaction for its detection 152 Pouget - and Cavalier J. Notes on Glycero-phosphoric Acid 216 Practical Chemistry and Qualitative Analysis Treatise on (Clowes) 7th edition, Prescott A. B. and Gordin,' H. M. Emetine octo-iodide and the extraction and Review 308 estimation of Alkaloids generally 74 - Estimation of Morphine in Opium 265 Hydrastine periodide and the assay of Hydraatis Canadensis 238 - Separate estimation of Strychnine and Brucine 75 --- - Hess W.H. Separation and identification of Coumarin and Preservatives Influence of Food on Digestive Enzymes 102 Priest M. and Moor C. G. Coffee Extracts their composition and analysis 281 Primulin 44 Prinsen-Geerligs - Use of basic Lead acetate in the Polarimetry of Sugar Ptomaine in Coffee Occurrence of a 36 Pump Automatic Mercury 224 Pyridine silico-tungstate 187 Pyrites Determination of Sulphur in 193 -_- Estimation of Pyrrhotite in 164 Pyro-catechin Reactions of 38 Pyrogallol Reactions of 38 -- and Iron salts Reactions of 164 Pyronines 44 Pyrrhotite in Pyrites Detection of 164 - Volumetric assay of Opium 8 Vanillin 162 solutions 47 - Gallic Acid and Tannin Reaction of 137 Qualitative Analysis Treatise on Practical Chemistry and (Glowes) 7th edition, Quercetin 45 Quinoline Yellow A.44 Quinonephthalones 44 Review 308 Raikow P. N. Chlorine compounds in Cotton Oil and its behaviour with the Phloroglucinol and Vanillin test 33 xxvi INDEX TO VOLUME XXIV. Raikow P. N. Detection of synthetical [Toluene] Benzoic Acid in the Resin -- Flash-point of dilute Alcohol and other Organic bodies 131 Rape Oil A-cetyl value of 322 Red Alizarin 45 - - Congo 43 Reed L. Rapid estimation of small quantities of free Phosphorus in Phosphorus paste 33 Refractometer Examination of Oils and Varnish with the 158 Reichard C. Volumetric determination of Bismuth 220 Reid E.E. Valuation of Saccharin 242 Resin Valuation of 136 Resins and Balsams Some recent methods for examining 77 Resorcin Reactions of 38 Reuter M. Volumetric estimation of combined Sulphuric Acid 25 Rhodamines 44 Richards 3'. W. Electrically-heated Drying Oven 307 Richaud A. Detection and estimation of Bromoform in toxicological work 210 Richmond H. D. Automatic Burette 2 - Composition of Milk and Milk products 197 sublimed product 286 - Estimation of Alcohol and Ether in the presence of Petroleum - and O'Shaughnessy F. R. Note on a possible source of error in modifications of the Leffmann-Beam method €or the estimation of Fat in Milk 146 I__-- - Rosier C. H. Estimation of Fah in Milk using Petroleuai Rideal Dr. S Assay of Belladonna Plaster 177 -- Formaldehyde 87 Ridenour W.E. Hydrogen peroxide as a test for Salicylic Acid 287 Riegler E. New Indicator for Acidimetry 166 Rimini E. Colour reaction for Vinyl Alcohol 267 Robinson Shortt v. Prosecution for selling adulterated Caper Tea 120 Rocques X. Preparation of a standard solution of Ethyl Aldehyde 37 -- Volumetric estimation of Acetic Aldehyde 213 Rcestr P. Composition of edible Locusts 285 Rosenheim O. and Schidrowitz P. Some comparative analyses of and digestion Rosier C. H. and Richmond H D. Estimation of Fat in Milk using Petroleum Rota A. R. Method of analysing natural and artificial Colouring matters 41 Roux and Maquenne MM. Note on Rjeldahl's method of determining Nitrogen 189 Roxycki - Estimation of Carbon in Iron by combustion 22 Rubidium and Czsium Separation of 110 Rung F.and Binz A, Estimation of Indigo on Fabrics 48 Rupp G. Ash of certain descriptions of Cinnamon 154 Rusting N. Estimation of Hydrastine in Extractum Hydrastis Fluidum 9 Ether 201 Ether as a solvent 172 New method of estimating Hydrazine 269 experiments with white and whole-meal Breads 227 Ether as a solvent 172 Saccharin Influence of on Digestive Ferments 103 -- Valuation of 242 -- in articles of Food and Drink Detection of 152 Saccharine liquids Wine etc. Detection of Cane-Sugar in 34 $afYrol 9 INDEX TO VOLUME XXIV. xxvii SaEron 47 Safranine T extra 43 Salicylic Acid Hydrogen peroxide as a test for 287 -- Influence of on Digestive Enzymes 103 Saliva ind Milk Oxy-Ferments of 79 Salkowski E. Estimation of Oxalic Acid in Urine 249 Saltpetre Chili Estimation of perchlorate in 26 -_- - Microscopic detection of perchlorate in 26 Saltpetres Estimation of perchlorates in 26 Sardine Oil Constants of 136 - Saponification number of 186 Sassafras bark Composition of 90 -- leaves Oil of 90 __- Oil Composition and characteristics of 90 Sausages Detection of Horseflesh in 73 Scammony Adulteration of with Galena and Starch 241 Scarlet Biebrich 47 Scarpitti N.and Simoncelli G. Piutti’s reagent for Alkaloids (Iodine-derivative of Schaefer G. L. New test for Cocaine 237 Schaer E. Notes on the Guaiacum reaction for the detection of Blood 266 Schey L. T. C. Apparatus for Distillation in high vacua 112 Schick R. Contributions to our knowledge of Colophony 136 Schidrowitz P.and Rosenheim C. Some comparative analyses of and digestion Schimmel and Co. Constitution of Oil of Orange flowers (Neroli) 155 Schon C. V. and Budde. C. C. Electrolytic method of delermining Nitrogen in Schroder K. Use of Potassium ferrocyanide for preparing standard Ferric solutions Schiiler G. Determinetion of Chromium oxide in Algerian Phosphates 52 Schumacher - and Jung W. L. Estirriation of Mercury in Urine by amalgamation, Scudder H. and Mulliken S. P. Simple colour reaction for Methyl Alcohol 212 Seal Water- for use when boiling Liquids in a reducing atmosphere 276 Seeman L. and Vanino L. Determination of Gold and its separation froni Platinum Selenious Acid Influence of HydrochIoric Acid in titrating with Sodium thiosulphate Sendtner R. and Juckenack A.Examination and characteristics of commercial Separator-slime Composition of Milk 201 Sesame Oil 99 Sestini F. Formation of Furfural from Starch and its derivatives 157 Sewage and Water exmination results 277 Seyda A. Colorimetric estimation o€ Iron in Water 51 - Preparation of Starch-Zinc iodide solution 82 Shark Oil Constants of 136 Shortt v. Robinson Prosecution for selling adulterated Caper Tea 120 Shuttleworth’s A. E. method of determining ash in Organic substances 271 p-Ethoxyphenylsuccinimide) 11 - Notes on Colophony 77 experiments with white a ~ ~ d whole-meal Breads 227 - - Oil of Cognac 184 Organic Substances 273 for volumetric purposes 303 274 Oil Constants of 136 Saponification number of 186 and Iridium 301 with special reference to the determination of 193 Fennel seed 12 xxviii INDEX TO VOLUME XXIV.Silicon Analysis of 276 Silico-Tungstic Acid Use of as a reagent for Alkaloids 187 Simoncelli G. and Scarpitti N. Piutti’s reagent for Alkaloids (Iodine-derivative of Simons F. D. and Crampton C. A, Detection of Caramel in Spirits and Vinegar 207 Sinapine Estimation of 153 Sjollema B. Determination of digestible Xitrogenous matter and albuminoid Nitrogen Skertchley PI. P. and Hehner O. Estimation of Pentosans and its application to Slag Basic (Thomas meal) Valuation of on the basis of its percentage of soluble Slater C. and Spitta E. J. Atlas of Bacteriology Review 55 Smith Professor E. F. Translator Organic Chemistry; or the Chemistry of the - H. N. and Leonard N. New test for Formaldehyde 86 -_- Bodnier R.and Leonard N. Analysis of Golden Syrup 253 Soaps Determination of the molecular weight of in Alcoholic solutions 247 Society of Public Analysts Annual Address to the 59 SOCIETY OF PUBLIC ANALYSTS PROCEEDINGS OF THE 1 29 37 85 113 141 169, Sod Oil or DBgras Analysis of I60 Soda Glass unsuitable for chemical apparatus 83 Sodium benzoate Influence of on Digestive Enzymes 103 - Microscopic detection of perchlorate i n 26 in Steel Note on Drown’s method of determining 53 p-E thoxy phenylsuccininiide) 11 in Foods and Feeding Stuffs 263 the analysis of Foods 178 Phosphoric Acid 305 Thomas Estimation of available ” Phosphoric Acid in 25 Carbon CompOUndS 3rd edition Review 279 Dinner of the 66 197 227 253 281 317 nitrate Estimation of perchlorate in 26 thiosulphate Influence of Hydrochloric Acid in titrating with with special reference to the determination of Selenious Acid 193 -- Tetrathionates in Copper as a reagent for 111 Soil Calcium carbonate in Estimation of 275 - - Carbonates in Estimation of 275 Hunius in Estimation of 103 Solanine Composition and reactions of 216 Soldaini A.and BertB C. Estimation of Oil of Bergamot 50 Solid Yellow N. 43 Soluble Nigrosin 44 SonniBMoret A. Valuation of Izydrogen peroxide 305 Sperm Oil 97 Spermaceti Acetyl value of 321 Spiller E. Hopkins 33 and Coburn D. L. Analysis of DBgras or Sod Oil 160 Spirits Detection of Methyl Alcohol in commercial 212 and Vinegar Detection of Caramel in 207 -- of Nitre Adulteration of with Potassium nitrate 87 Spitta E.J. and Slater C. Atlas of Bacteriology Beview 55 Sprengel tube Modification of the 277 Starch Maize Detection of in Wheat-meal 150 pressed Yeast Detection of added 89 Zinc iodide solution Preparation of 82 in Potatoes and a sensitive reaction for its detection 152 - Acetyl value of 321 in black and white Mustard-seed Detection of 3 INDEX TO VOLUME XXIV. xxix Stearin (“ Vegetal ”) Detection of Cotton-Oil in Lard by means of the Phytosterin Steel Silicon in Note on Drown’s method of determining 53 Steinfels W. Storage vessel for delicate Volumetric solutions 223 Stickleback Oil Constants of 136 Stokes A. W. Automatic Burettes 4 Streatfield F. W. und Eynon L. Apparatus for the estimation of Carbon and Strychnine and Brucine Separate estimation of 75 -- silico-tungstate 188 Strzpowski C.Use of Persulphates to detect Albumin in Urine 49 - Microscopic identification of Blood 210 Stubenrauch. See Von Stubenrauch. Stutzer A. and Hartleb R. Estimation of Calcium carbonate in Soil 275 Sucrose Influence of temperature on the specific rotation of and method of correct-Sugar Cane- in Milk Detection of 144 - in Wine Saccharine Liquids etc. Detection of 34 -_ Determination of Influence of temperature on the optical 157 Sugars Use of basic Lead acetate in the Polarimetry of 47 Sulphides Metallic soluble in Ammonium sulphide Reaction of 22 Sulphites and Thiosulphates Estimation of 23 Sulphonal Isolation and identification of in Forensic work 129 Sulphur in Asphalt Determination of 48 test.Notes on the Bomer process 149 Tungsten in Determination of 164 Saponification number of 186 Hydrogen in volatile Organic liquids 139 Influence of Bacteria on the decay of Cement 251 ing readings of compensating Polarimeters 288 in Molasses Estimation of 149 Coal Determination of total 272 Iron Volumetric estimation of by means of Arsenious Acid 302 pyrites Determination of 193 ____- - _- - Russian Petroleum Determination of 272 Sulphuretted Hydrogen Apparatus for the employment of 11 1 Sulphuric Acid Estimation of in presence of Iron 164 -_-___ Volumetric estimation of combined 25 Sumach Silician and its adulterants 49 Sundvik E. E. Humble-Bees’ Wax 39 Syrup Golden Analysis of 253 Gravimetric estimation of in presence of Iron 137 Solubility of Methane and Ethane in fuming 154 Tallow 97 Tannin New method of estimating 137 Tannins Estimation of and the influence of Gallic Acid on the process 160 Tar Wood- Examjnation of Creosote 292 Tea Caper,,90 117 - Government Laboratory and Mineral matter in 333 Telluride Gold ores Assay of 17 Terpenes and Oil of Aralia Nudicaulis Characteristics of the 294 Tetrathionates in Sodium thiosulphate Copper as B reagent for 111 Thal,.R. Henriques’ process for the analysis of Indiarubber articles 16 Acetyl value of 327 Gallic Acid and Pyrogallol Reaction of 137 3 Prosecution for selling adulterated 120 -_ -xxx INDEX TO VOLUME XXIV. Thiazines and Thiazoles 44 Thiel A. and Kuster F. W. Gravimetric estimation of Sulphuric Acid in presence Thiele EL Laboratory ball-Mill 222 Thill J.Volumetric estimation of Sulphur in Iron by means of Arsenious Acid 302 Thio-carmine R 44 Thiosulphates Sulphides and Sulphites Estimation of 23 Thomas Meal Estimation of total Phosphoric Acid in 251 Phosphoric Acid 305 Thyme Oil of Composition of 101 Timpe H. Areometric determination of Fat in Milk 205 Tin in Tin ores Electrolytic estimation of 108 Titanium from Iron Separation of 81 Tolidine and Benzidine Reaction for 290 Tollens B. A. E. Shuttleworth’s method of determining ash in Organic substances 271 Tower 0. F. Determination by combustion of Carbon and Hydrogen in Organic TOXICOLOGICAL ANALYSIS. ABSTRACTS 11 129 210 266 287 Trasciatti D. and Montemartini C. Determination of Morphine in Opium 264 Trillat A, Detection and estimation of Methyl Alcohol in Ethyl Alcohol 13 - 7 - ---- Ethyl Alcohol 211 - Estimation of Gelatine in Gums and Food substances 35 of Iron.The importance of the Ionic theory in Analytical Chemistry 137 - (Basic Slag) Valuation of on the basis of its percentage of soluble Slag Estimation of ‘‘ available ” Phosphoric Acid in 25 substances containing Nitrogen 290 of Methyl Alcohol in commercial Spirits 212 Tungsten in Steel Determination of 164 Turpentine Oil of Refractometer number of American 159 Ulsch K. Estimation of Acids from the volume of Hydrogen evolved on treatment - Nitrogen estimations Impure Iron a possible source of error in 80 Uranium from Iron Separation of 81 ____- Zirconium Separation of 82 Uric Acid Estimation of 164 Urine Acetone in Detection of 155 - Albumin in Test for 102 c_- 3- Use of Persulphates to detect 49 - Albuminous substances in Determination of 289 -_ Bile Pigments in Detection and estimation of 249 - Mercury in Estimation of by amalgamation 274 Oxalic Acid in Estimation of 249 - Phenols in Determination of 250 - Wine Beer and Cider Estimation of Chlorides in 49 with metals 304 - Modification of DenigB’s method of estimating 189 Van Breukeleveen M.Microscopic detection of perchlorate in Chili Saltpetre 26 Van Melckebeke R. Detection of Acetone in Urine 155 Vandevyver L. N. Apparatus for estimating Melting-poin ts 84 Vanillin and Coumarin Separation and identification of 162 - mixed with Acetanilide 16 Vanino L. und Seeinan L. Determination of Gold and its separation from Platinum Varnish and Oils Examination of with the Refractometer 158 Veratrine Analysis of commercial 209 and Indium 30 INDEX TO VOLUME XXIV.xxxi Vignon L. New method of estimating Tannin 137 Vinegar Contribution to our knowledge of Wine 151 c____ and Spirits Detection of Caramel in 207 Vinyl Alcohol Colour reaction for 267 Violamine R. 44 Violet Acid 4BN 47 Alkali 47 Virchow C. Question of the retention of Phytosterin in the animal system on Feeding Vitali D. Detection of Acetylene in cases of Poisoning therewith 11 Volumetric solutions Storage vessels for delicate 223 Von Richter V. Organic Chemistry ; or the Chemistry of the Carban compounds, Von Stubenrauch L. Detection of Iodoform in aqueous fluids 37 Von Winkler H. Apparatus for increasing the speed of Filtrations 55 Wagner P.Valuation of Basic Slag (Thomas meal) on the basis of its percentage of Walker C. F. and Gillespie D. N. H. Volumetric Estimation of Alkalies and Acids - P. H. Some applications of Hydrogen peroxide in quantitative analysis 81 Water action of a hard on certain metals 306 -- ammonia Nitrates and Nitrites in Determination of 221 -- Barium compounds in Artesian Well Occurrence of 67 - Chemical and biological analysis of (Pearmain and Moor) Review 166 - Gases dissolved in Apparatus for measuring the 195 - - Hardness of relative value of Lacmoid Phenacetolin and Erythosin as Indicators in determining the by Hehner’s method 194 .- - Iron in Colorimetric estimation of 51 -_- Microscopy of drinking (Whipple) Review 166 -- Nitrates in Method fur facilitating the colour cornpaxison in the determination -- Nitrous reaction in a drinking False 27 -- Oxygen in Determination of 306 -- and Sewage examination results 277 -- Blast New form of 54 -- in Butter Proportion of 148 - -seal for use when boiling Liquids in a reducing atmosphere 276 Wax Bees’ Acetyl value of 321 with Cotton-seed Oil 283 -- free Nitric Acid in Toxicological work 11 Some reactions of Chloric Brornic and Iodic Acids 165 3rd edition Review 279 soluble Phosphoric Acid 305 by means of Iodine 80 of by the Phenol-sulphonic Acid method 222 Carnauba Acetyl value of 321 Humble-Bees’ 39 Wool Acetyl value of 321 L_ - Alcohols,.Acetyl value of 321 Webkr W.and Hintz E. Analysis of Incandescent Mantles 20 Weger M.Examination of Oils and Varnish with the Refractometer 158 Weiginann H. Alteration of Milk-Fat in the ripening of Cheese 149 Weintraub E. and Lunge G. Determination of unaltered Cellulose in Gun-Wells J. S. C. and Lenher V. Tests for Boric Acid 304 Weyl T. and Erlwein G. Recognition of Ozone in presence of Nitrous Acid atld Wheat Meal Detection of Maize Starch in 150 cotton 217 Hydrogen peroxide 8 xxxii INDEX TO VOLUME XXIV. Whipple G. C. Microscopy of drinking Water Review 166 White J. Caper Tea 117 Wijs J. J. A. Coinparison of the methods of Iodine absorption in the analysis of Wiley H. W. Influence of temperature on the specific rotation of Sucrose and Willenz - Analysis of commercial Chrome Yellow 19 Wilson H. Assay of liquid extract of Ipecacuanha 128 Wine Fluorine in Detection of 285 - Liquorice in Detection of 260 - Beer Cider and Urine Estimation of Chlorides in 49 - Saccharine Liquids etc.Detection of Cane-Sugar in 34 - Vinegar Contribution to our knowledge of 151 Wines Notes on Cazeneuve's method of detecting artificial Colour in 89 Winkler L. W. Determination of Ammonia Nitrates and Nitrites in Water 221 ~- . See Von Winkler. Wirthle F. Detection of Cotton-Oil Stearin (" Vegetal ") in Lard by means of the Witter W. Valuation of Gold samples 299 Wolff J. Composition and Analysis of Chicory 261 ~- - Reaction for Benzidine and Tolidine 90 Wolowski K. A. Estimation of Indican 248 Wood-Naphthas Official examination of for methylation purposm 234 Tar Creosote Examination of 292 Wool Wax Acetyl value of 321 - Alcohols Acetyl value of 321 Woolsey J.F. Adulterated Gamboge 37 Worstall R. A. Solubility of Methane and Ethane in fuming Sulphuric Acid 154 Wort Malt and Beer Estimation of the Nitrogenous constituents of 184 Yeast Detection of added Starch in pressed 89 Yellow Acid 47; Alizarin A 45; Brilliant 47; Cotton R 47; Diamond 43; Dia-niond R 47; Martius 46; Naphthol 43; Quinoline A 4 4 ; Solid N 43 ; Victoria 43 Occurrence of Barium compounds in Artesian Well Water 67 fats 94 met hod of correcting readings of compensating Polarimeters 288 Phytosterin test. Notes on the Bomer process 149 Azo-colour in Fats etc. Testing for 73 Zega A, Microscopy of Butter 206 _____I mzd Majstorovic R. Determination of the Iodine value of Fatty Acids 245 Zinc and Manganese Remarks on the determination of as Sulphide 51 Nickel Separation of 191 Copper Mercury or Bismuth from Aluminium Separation of 17 in German-dried Fruit Amount of 8 - in German Silver and similar alloys Volumetric estimation of 301 - ores containing Alumina Determination of 221 Zirconium from Uranium Separation of 82 BILLING AND SONS PRINTERY QUILDE'ORD

ISSN:0003-2654    

DOI:10.1039/AN89924BA001

出版商:RSC    

年代:1899

数据来源: RSC

摘要:

2 THE ANALYST. A N A U T O M A T I C B U R E T T E . BY EL DROOP RICHMOND. (Read at the Meeting, June 1, 1898.) SOME years ago it was the custom in my laboratory to measure off the sulphuric acid for the Leffmann-Beam process by means of a 100 C.C. burette, which was filled by means of a siphon with a tap to it ; the acid ran in at the top of the burette, and the operator had to stand by the burette till the acid reached the zero mark, and then to turn off the tap. To prevent the possibility of accidental overflow of the acid, it occurred to me to L Fro. 1. F ~ G . 2. * -I - - -3 -h F I G . 3. F-G. 4. fill the burette from the bottom, using a three-way tap, and to cork up the top with acork carrying a tube of diameter so small that the volunie of the acid in the tube could be neglected (Fig.1). A trial convinced me that the method was slow, owing to the time that sul- phuric acid took to run out of t h e narrow tube, and a little consideration revealed the fact that the error was much larger than was at first glance apparent. The following demonstration will show the nature of the errors intro- duced. The level of the acid a de- pends not only upon the level of the end of the tube, but on the pressure on the air in the space above ; if /I, and h1 represent the heights to which the acid rises when the stock-bottle is full and empty respectively, the volume of air in the space will vary in the proportion ofTHE ANALYST. 3 760 to x -____~__--- 760 760+ahx - 13.6 d 760 + n,h, x 1s a xx- where x = volume of air at 760 mm. pressure, d = density of liquid filling tube ; taking - - FIG.5. this it is forced x as 10 c.c., the distance from h to hl as 250 mm., and d as 1.82, which were the approxjmate values of the trial apparatus, a variation of nearly 0-5 c.c between the volume delivered when the stock-bottle is full and nearly empty is found ; this variation is much greater than that due to the actual volume of acid in the'tube, which was less than 0.2 C.C. ; both variations go in the same direction, and the combined error quite unfits this apparatus for any- thing more than rough work. A fairly obvious modification was to place the air-chamber above, instead of below, the effective zero point ; this was accomplished by drawing out the end of the burette to a narrow tube, and en- closing this in an air-chamber.The following diagrams will show two forms of accomplishing this end. In Fig. 2 the chamber and an exit-tube for the excess of liquid are made all in one piece ( A form); in Fig. 3 the exit-tube passes through a cork (B form). A further modification, which was not so accurate, but was convenient where great accuracy was not desired (e.g., the measurement of sulphuric acid for the Leffmann- Beam process, for which I have used it for the last four years), is shown at Fig. 4 (C formj. This enables an ordinary burette to be used, and, provided that the lower air-space is kept as small as possible, is quite accurate enough, and has the advantage that the zero point can be altered if desired, though it must be borne in mind that an alteration of the zero point will cause an alteration in the extent of the error, Of these forms B is pre- ferable, and is capable of greater accuracy than C, and is not so liable to break as A .In the case of corrosive liquids the connection between the stock-bottle and the burette is made by a siphon and the well- known air-trap, which enables an indiarubber connection to be used, and diminishes the risk of breakage. The disgram (Fig. 5 ) shows a burette (C form) with all connections ; after a, measurement has been performed the tap is turned half round, and the burette is automaticdly filled to the zero point ready for use when required. The liquid siphons over from the stock-bottle, fills the burette to the top, and then runs over into the air-chamber ; from UD bv the Dressure of the incorninn liauid UD the ascending tube till4 THE ANALYST. the level is equal to that in the stock-bottle; the zero is quite automatically adjusted and requires no attention. When the liquid is run out, air enters through the ascending tube and bubbles through the liquid in the air-chamber. When the burette is again filled the liquid in the air-chamber is forced back into the bottle.

ISSN:0003-2654    

DOI:10.1039/AN8992400002

出版商:RSC    

年代:1899

数据来源: RSC

摘要:

4 THE ANALYST. AUTOMATIC BURETTES. BY A. W. STOKES, F.I.C. (Read at the Meeting, November 2, 1898.) DURING the last few years I have interested myself in devising automatic apparatus for the purpose of rapidly, accurately, and safely measuring liquids, especially such liquids as strong ammonia and sulphuric acid. To be truly automatic, the apparatus should without watching- 1. Fill itself. 2. Empty itself. 3. Refill itself at the same time that it is emptying. 4. Be incapable of letting the whole of the supply run from the reservoir. 5. Need only one motion of the hand for all these operations. 6. Be adjustable to deliver any required quantity. Only one of the apparatus I show you to-night fulfils all these requirements. Fig. 1 is a plan I contrived that for exactitude excels all the apparatus hitherto introduced for this purpose.In this the measuring vessel, having a lateral opening at the top and another at the bottom, itself revolves. The lower end connected with the supply revolves in a sleeve, and the upper end, in communication with the over- flow, revolves in another sleeve. The instant the measuring vessel is revolved all connection with the reservoir is cut off, so that an absolutely exact quantity is con- FIG. 1. tained in the measure. Half a revolution brings its lower opening to the exit-tube, This form takes up its own supply of air, so and its upper opening to an air-inlet.THE ANALYST. 5 that the reservoir may be a closed vessel, if necessary. I t , however, does not at the same time refill itself, nor can the quantity it delivers be varied without changing the measuring vessel.. Fig. 2 involves a new principle-that is, the introduction of a capillary tube into the measuring vessel so as to vary its capacity at will, and to avoid connecting the reservoir with any over-flow pipe. The capillary tube really forms an over-flow pipe, but as it is carried straight up above the level of the reservoir there can be no actual over-flow. By forcing this tube down into the measuring- vessel, the capacity of this latter is lessened, so that it will deliver a smaller quantity than before: The capillary tube also protects the cork through which it passes from corrosive liquid that one may be measuring. But when the level of the liquid in the reser- voir varies, it would apparently result that a varying quantity of liquid would be de- livered, due to the greater or lesser height of the over-flow in the capillary tube.But a capillary tube may be used whose whole length would be filled by EL single drop. Evidently, then, the variation of a few inches in the level of the reservoir will not vary the quantity de- livered by more than some fraction of a drop. Time, however, is lost with this appa- ratus, because it does not refill itself at the same time that it is emptying. being acted upon by any ;i FIG. 2. A FIG. 3.6 THE ANALYST. In Fig. 3 I duplicated the measuring-vessel, and used a capillary tube in each. By the kindness of Messrs. Lister, of Dursley, who have patented this and some other of my measuring devices, I am able to show you specimens to-night. It fulfils all six of the conditions I noted at the beginning of this paper, as required of a truly automatic measure, and needs only a half-turn of the tap to repeat the measuring indefinitely. I t s supply-pipe, acting as a syphon, can be dipped into any ordinary reagent-bottle without removing this from its shelf, and it will then deliver any required quantity. When different quantities are required alternately, one capillary tube can be pushed down further than the other, so that one measuring-tube will, for instance, give 5 c.c., the other 10 C.C. at every half-turn of the tap. By using a capillary tube with a bulb blown on it accurate quantities far larger than the capacity of the measuring vessel can be delivered. The measuring vessel in such case serves only as a regulator, the bulb holding most of the quantity to be delivered.

ISSN:0003-2654    

DOI:10.1039/AN8992400004

出版商:RSC    

年代:1899

数据来源: RSC

摘要:

6 THE ANALYST. ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. FOODS AND DRUGS ANALYSIS. Alteration in the Character of Butter Produced by Feeding with Fat. G. Baumert and F. Falkc, (Zeit. fiir Untersuch. der Nalzr. uud Genussmittel, 1898, 665-678.)-The authors give the results of a series of experiments undertaken with the view of testing the effect produced upon butter by feeding cows upon fats. The experiments were made upon two cows, Swiss and Dutch. The fats used- sesame oil, cocoanut oil, and almond oil-were selected on account of their dissimi- larity from each other, as well as from butter itself. They were administered in the form of emulsions. The following plan of feeding, embracing five periods of twenty days each, was carried out : (1) Hay and rape meal only. (2) Hay and rape meal with sesame oil.(4) Hay and rape meal with almond oil. The milk was passed through a separator and the cream churned to butter. The butter obtained was then at once melted at 40" to 50" C., allowed to stand for some time at the same temperature, and the fat clarified by filtration. Its examination included the determination of the Kottstorfer and Reichert-Meissl numbers, the Hub1 and iodine numbers, the melting- points and refractions. The results showed that the butter fat was not only greatly changed in character through the feeding with the fats, but that the alteration, as indicated by the numbers obtained, was always in the direction of the numbers characterizing the three fats used in the experiments. I n other words, the butter fats produced by feeding with Eesame oil, cocoanut oil, and almond oil, exhibited the same characteristics as would be found in artificial mixtures of butter fat with the three oils in question.This is clearly shown in the following table of average results : (3) Hay and rape meal with cocoanut oil. (5) Hay and rape meal only.THE ANALYST. 7 of the Periods. 1 Swiss Dutch cow. +2*4 +5*4 -0.6 Swiss cow. ---- 224 204 237 Fat admin- istered, I + 17.6 - 9.2 + 13.6 - Period 111. (Almond oil -0.5 Fat rdmiii- stered. -- - 190 255 195 - Dutch cow. -- 223 206 230 207 216 ~ HUM Number. Reichert-Meissl Number. I Dutch , Swiss cow. cow. I 29.5 15.7 18.6 15.3 24.4 44.3 53.9 37.1 50.9 41.2 Fat 2dmin- iatered. -- I 116 9 98 - Dutch cow. - 45 -0 52.9 35.2 53.9 44.5 The attempt to detect sesame oil in the butter produced in feeding with this oil As regards the melting - point determinations, these yielded the following by means of the furfurol and hydrochloric acid test was, however, not successful.averages : Period. I. 11. 111. IV. v. Swiss cow ... 34.16' 37.00" 33.58" 34-28' 34 50" Dutch cow ... 33.96" 36.76" 34-76' 34.50" 35-15' Compared with the melting-point of pure butter-fat, these results are all very high, the highest being in the case of the sesame oil feeding (II.), which agrees with the results of previous observers (cf. Reprint, vol. xxiii., p. 255). H. H. 13. S. On the Volatile and Insoluble Fatty Acids in Butter. R. Henriques. (Chem. Rev. Fett u. Ham-Id., vo1.v. [9 1, pp. 169-172.)-The author investigated several samples of pure butter exhibiting unusually low Reichert-Meissl values, with the idea of devising a method for distinguishing these butters from mixed butters.It is based on the differences in the actual quantity of and the average molecular weight of the volatile and non-volatile fatty acids. The results, however, showed that butters with a normal R.-M. number contained 5 to 6 per cent., those with an abnormal 4 to 5 per cent. of volatile fatty acids, the average molecular weight of which varied from 93-3 to 99.8 ; hence the results have but a negative value for analytical practice. With regard to the insoluble fatty acids, in these the Hehner number ranged between 86-5 and 89-1 for normal and 88.96 to 90.68 for abnormal butters; but a, difficulty arose in the estimation of the average molecular weight, in that the values found on drying at 105" to 110" C.(viz., 267 to 270) differed from those (256.3 to 263) obtained when the drying was effected at the ordinary temperature in a vacuum desiccator. The author, however, considers that, assuming butter to contain a large pro- portion of oleic acid, the above figures indicate that a considerable amount of an acid of lower molecular weight than palmitic acid is present ; and that by isolating this acid and separating the unsaturated from the saturated acids it is not improbable, provided the assumption of a low average molecular ,weight for this undetected acid be found correct, that the presence of extraneous fats in butter may be discovered by the relatively higher molecular weight of the saturated acids they contain.C. S.8 THE ANALYST. The Action of Formaldehyde on Flesh. (Zeit. Fleisch 26. &?itch. Hyg., 1898, viii., 232.)-The author has made experiments on the preservation of flesh by means of an 8 per cent. solution of formaldehyde. He finds that beef is preserved without the production of any unpleasant odour, but that the meat is only eatable for a short time after the treatment with the antiseptic. Horseflesh, on the other hand, invariably develops a characteristic intense smell within forty-eight hours, resembling that of roast goose-flesh. Only in one instance was a faint suspicion of this odour met with in the case of beef, and the author suggests that this difference may give a further means of distinguishing between the two kinds of flesh.E. Ehrlich. C. A. M. The Amount of Zinc contained in German Dried Fruit. P. Xulisch. (Zeit. ungew. Chem., 1898, 1015-1016.)--The author states that the zinc so frequently met with in American dried fruit is derived not from any addition of zinc salts, but from the action of the acid juices of the fruit on the zinc trays of the drying apparatus. On continued use, these become coated with a hard crust of dried juice, which largely prevents the fruit from coming in contact with the metal, and in such dried fruit the amount of zinc is naturally less. Since all modern German drying apparatus is constructed on the American plan, with zinc-wire trays, the author has examined different kinds of dried Gerinan fruit in order to determine to what extent they were contaminated with the metal. The quantities found in 100 grammes of fruit containing the usual commercial percentage of water were : Gramme.Apple rings a ... ... ... ... ... 0431 Apple chips a ... ... ... ... ... ... 0.023 ... ... ... ... ... 0.021 ... ... ... ... ... 0.027 Pear slices a ... ... ... ... ... ... 0.020 ... ... ... ... . . . 0.026 9 , 7 7 b 9 , 9 9 b ..- 3 , $ 7 b ... All the samples thus contained an amount of zinc not much less than the mean quantity found in American apple rings (cf. ANALYST, xx., 251). C. A. hl. A Volumetric Assay of Opium. A. B. Prescott and H. M. Gordin. (Jozw. Amer. Chem. SOC., 1898, xs., 724-728.)-This is an application of the authors' general method for the estimation of alkaloids (cf. ANALYST, xxiii., 324).The opium alkaloids are liberated by the action of ammonia in the presence of certain solvents. The free narcotine, papaverine, codeine, and thebaine are removed by percolation with benzene, after which the morphine is extracted by percolation with acetone. The acetone is evaporated, and the residue taken up with lime-water, which completely dissolves and purifies the morphine. The solution is filtered, acidulated with hydrochloric acid, and the alkaloid estimated as periodide by titration with Wagner's reagent. Tho details of the assay are as follows : 1 gramme of the finely-powdered opium is triturated in a mortar with 2 or 3 C.C. of a mixture of 5 C.C. of ammonia, 5 C.C. of alcohol, 20 C.C. of ether, and 10 C.C. of chloroform. The covered mortar is left for about three hours, with an occasional gentle shake, after which about 15 grammes of dry finely-powdered common salt are stirred into the pasty mass.I t is then left in a warm place (30" to 35" C.) for two or three hours, and afterwards placed in aTHE ANALYST. 9 desiccator containing sulphuric acid and a dish of parafin wax until perfectly dry. The contents are next transferred to a small glass percolator (22 cm. by 1-3 em.), and percolated with benzene until the percolate is colourless and gives no turbidity with Wagner's reagent. The dish beneath the percolator is replaced, and the percolation continued to complete exhaustion with acetone, as much as 200 C.C. of the solvent being usually required. The acetone extract is evaporated to dryness at a tempera- ture not exceeding 45" C., the residue triturated with fresh lime-water, the solution poured without filtering into a stoppered cylinder of 100 c.c., the dish washed out with lime-water, and the liquid in the cylinder made up to 100 C.C.with lime-water. The cylinder is well shaken for half an hour, and filtered into a second cylinder unti1,the filtrate amounts to 50 C.C. This liquid is rendered just acid with 10 per cent. hydro- chloric acid and 25 C.C. of the & iodine solution run in from a burette with constant shaking of the cylinder. After the addition of water to any convenient mark in the cylinder, the latter is shaken for about twenty minutes, until on standing the super- natant liquid (in which there should be an excess of iodine) is perfectly clear.An aliquot portion (one half) is then filtered off and the excess of iodine titrated with standard thiosulphate. The amount of iodine consumed by the alkaloid multiplied by the factor 0.0094793 gives the percentage of morphine in 0.5 gramme of the opium. The precautions most essential are : (1) That the opium residue be thoroughly dry before percolation ; (2) that the acetone should not contain anything distilling below 54" C. or above 58" C. : and (3) that after the excess of iodine has been added the cylinder be continuously shaken until the supernatant liquid is quite clear. The following were the results obtained by this method in the assay of three samples of commercial opium : A 1 2 3 B l 2 3 c 1 2 3 Opium Taken. Grammes. ... 1.0036 ... 1.008 ... 1.0022 ... 1.0033 ...1.0023 I . . 1.0026 ... 0.99639 ... 1 -0016 ... 0.9988 ... ... ... ... ... ... ... ... ... Iodine Consumed by 0.5 gramme. 0.116644 0.1 167 3 2 0.11 6642 0.08872 0.08872 0.08873 0.096319 0.097219 0.094552 ... ... ... ... ... ... ... Morphine Per cent. 17.41 17.37 17-44 13.25 13-20 13.21 14.48 14-55 14-19 C. A. bf. Estimation of Hydrastine i n Extractum Hydrastis Fluidum." N. Rusting. (Pharm. C. H., 1898, xxxix., 787; through Chem. Zeit, Rep., 1898j 289.)--.Ten grammes of the extract are weighed into a large flask, diluted with 20 C.C. of water, and boiled and agitated till the total weight is reduced below 20 grammes. After cooling, water is added to make the weight exactly 20 grammes, a little infusorial earth introduced, and the whole filtered. Ten grammes of the filtrate are shaken with 25 C.C.of spirit and 3 C.C. of 10 per cent. ammonia.; after a few minutes 25 C.C. of petroleum ether are run in, the liquid is again agitated, and 2 grammes of traga- canth are added. Forty C.C. of the clear ethereal liquid (equal to 4 grarnmes of the extract) are evaporated down to about 15 C.C. over warm water, and the vessel is put10 THE ANALYST. aside for several hours in a cool place. poured off, and the hydrastine crystals dried in the water-oven and weighed. The supernatant liquor is then cautiously F. H. L. Notes on Estimating Eucalyptol. L. F. Kebler. (Amel.. Journ. Plzarnz., 1898, lxx., 492-494.)-Each species of the eucalyptus genus (about 120) apparently yields a distinctively characteristic oil, of which the United States Pharmacopoeia recognises that distilled from the fresh leaves of E.globzclus, E. oleosa, and some other species. With regard to the differentiation of the officiaI oils from the others the author points out that the specific gravity and rotatory power may be valuable criteria, but that the oil can be so niixed as to make these factors of little service. The phel- landrene test is also serviceable, but the chief desideratum is to know the amount of eucalyptol in the oil. In 1894 L, R. Scammell took out a patent for the preparation of eucalyptol on a large scale (Eng. Pat. 14,138), which was bawd on the fact that on adding con- centrated phosphoric acid (specific gravity 1.75 to 1-78) to the oil at the ordinary temperature (not exceeding 60" F.), a crystalline compound of eucalyptol phosphate separated out, which, after being purified by pressure, or centrifugal force, was decomposed with hot water.Faulding (Chemist and Druggist, 1895, 310) examined this process as applied to the quantitative estimation of eucalyptol and found that it gave excellent results. Helbing (Phaym. Record, xxxiii., 26), however, came to the conclusion that it was valueless for quantitative work, and the author's results confirm this. By a modification of the process he has succeeded in obtaining closely approxi- mate results in the following manner : Eight grammes of the oil are weighed into a beaker, which is cooled in ice-water. Four C.C. of phosphoric acid (1.75) are added, the beaker again placed in ice-water, and, after cooling, the contents thoroughly mixed by means of a glass rod. The eucalyptol phosphate is removed, purified by heavy pressure in folds of filter-paper, and weighed. It is then decomposed with hot water, the liberated phosphoric acid titrated with standard alkali, and the eucalyptol obtained by difference. In some cases it is necessary to add more phosphoric acid, especially with pure eucalyptol. The results obtained by this method with pure eucalyptol and a number of oils are given in the subjoined table, in which the direct percentage of eucalypt01 was obtained by Scammell's process. No. Specific Gravity at 15" C. 0.9350 0.9153 0.9116 0.8912 0.8955 0.8876 09081 0.9424 Grammes of Solid ' Encalyptol Phosphate. ~ ~~~ 14.78 10.70 8.10 7.13 3.50 did not congeal tol, by difference. to], direct. 73-62 31.20 23.17 24.29 23.37THE. ANALYST. 11 Of these samples No. 1 was pure eucalyptol, 2 and 8 were special oils at a high price, and the remainder such as are commonly met with in the wholesale trade. C: A. M.

ISSN:0003-2654    

DOI:10.1039/AN8992400006

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年代:1899

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THE. ANALYST. 11 TOXICOLOGICAL ANALYSIS. Piutti’s Reagent for Alkaloids (Iodine-derivative of Para-ethoxyphenyl- succinimide). G. Simoncelli and N. Scarpitti. (Gaxx. chim. Ital., 1898, xxviii. 1121, 171 ; through Chem. Zeit. Rep., 1898, 279.)-The authors have investigated several iodine reagents for alkaloids, including those of Bouchardat and Selmi, and they find the most delicate to be one of the substances recommended by Piutti- viz., the iodine derivative of p-ethoxyphenylsuccinimide. This is prepared by treating the h i d e with a solution of iodine and potassium iodide in acetic acid. F. H. L. Detection of Acatylene in Cases of Poisoning therewith. D. Vitali. (Boll. chim. farm. , 1898, xxxvii., 449 ; through C7zem. Zeit. Rep., 1898, 247.) -The suspected blood is mixed with 5 or 8 per cent.of pure acetone, placed in a retort, and distilled into an empty condenser and a set of absorbing bulbs containing more acetone. The retort is heated on a water-bath, the condenser and bulbs kept cold in ice. The acetone passes over, carrying the acetylene with it, and the latter may be identified by its characteristic reactions. Hydrogen sulphide and phosphide, which often occur in the crude gas, also dissolve in the acetone, and can be sought for therein. F. H. L. - . - -~ ~- Detection of Free Nitric Acid in Toxicological Work. D. Vitali. (Oester- reich. Chem. Zeit., 1898, 333.)-The organs to be examined are warmed on a water- bath, water being added if needful, and freshly precipitated barium carbonate is intro- duced, a little at a time, as long as it dissolves.The mixture is then evaporated to dryness, and the residue boiled three or four times with an equal volume of absolute alcohol. By this procedure the calcium and magnesium nitrates are brought into solution, whilst sodium nitrate, the calcium nitrate naturally present in the organism, and the barium nitrate formed by the action of the free nitric acid upon the barium carbonate, remain in the residue. The alcoholic solutions are then evaporated to dryness, the residue taken up with water and neutralized very carefully with solution of barium hydrate. The fluid is then again evaporated to dryness, and treated with absolute alcohol. The undissolved residue is taken up with water, the solution treated with a little lead acetate, to precipitate organic matter, and filtered.The filtrate is then treated with hydrogen sulphide, to remove the lead, filtered, and the clear filtrate concentrated by evaporation, and dried in an exsiccator. The residue is examined for crystals of barium nitrate, which can be recognised by their crystalline form and by the usual tests. In this way it is possible to determine those nitric acid12 THE ANALYBT. compounds with albuminous bodies (acidalbumins) which are soluble in alcohol, The insoluble residue from the first treatment with alcohol contains, as already mentioned, the sodium nitrate, the barium nitrate resulting from the treatment with barium carbonate, and the calcium nitrate which must be regarded as a normal con- stituent of the body. I t is made slightly alkaline with sodium carbonate, by which the nitric acid of the acidalbumins insoluble in absolute alcohol is neutralized, and the barium nitrate resulting from the free nitric acid is converted into sodium nitrate, whilst the calcium and sodium nitrates remain unchanged.The solution is filtered, the filtrate evaporated to dryness, and the residue treated with boiling absolute alcohol, which takes up the calcium nitrate, whilst leaving the sodium nitrate undissolved. The insoluble portion is dissolved in water, treated with a slight excess of lead acetate, the solction filtered, and the lead separated by hydrogen sulphide. The clear colourless fluid which is thus obtained is concentrated by evaporation, and dried in an exsiccator. Crystals of sodium nitrate in this residue can then be detected by the usual tests.Another method which the author has used successfully is as follows: The intestines are cut into small pieces, and treated with freshly precipitated strychnine. As strychnine nitrate has an acid reaction, the neutralization cannot be controlled by means of litmus paper, The mixture is dialyzed, the residue twice extracted with warm water, the filtered fluids evaporated to dryness, and the residue treated with boiling alcohol. The alcoholic solution is then filtered, evaporated to dryness, the residue taken up with water, decolorized by treatment with lead acetate, followed by hydrogen sulphide, and the filtrate concentrated. Strychnine nitrate, formed by the union of the strychnine with free nitric acid, if present, would here crystallize out, and be determinable in the usual way.H. H. B. S. Destruction of Organic Substances in Chemico-Forensic Work. C. Kippen- berger. (Zeit. fiir Untemuclz. de.i Nahr. m d Genussmittel, 1898, 683-687.)-Villiers a short time since (Conzpt. Rend., 1897, 1457) advised the use of a mixture of nitric and hydrochloric acids, with the addition of a solution of a manganese salt, for the destruction of organic substances. He stated that with this mixture the liver, spleen, and lungs could be oxidized in a few minutes, and the muscles within an hour-much more quickly, in fact, than by the use of potassium chlorate and hydrochloric acid, as recommended by Fresenius and Von Babo. The author is unable to confirm this, but found, on the contrary, that in order to complete the action it became necessary to add potassium chlorate from time to time with continued heating. The experiments made with Villiers’ method, however, led to the trial of a manganese salt in con- junction with potassium chlorate and hydrochloric acid, and in this case the author found a decided acceleration of oxidation to result from the use of manganese. The most suitable manganese compounds for the purpose are manganic dioxide and manganous chloride, of which the former has the advantage of being a stock reagent in every laboratory. The sulphate is less suitable, on account of the possibility of metals in the case of metallic poisoning (e.g., lead, mercury, or silver) becomingTHE ANALYST. 13 converted into insoluble sulphates, and so causing difficulties in the subsequent analysis. It is sufficient to add a little manganic dioxide to the substance mixed with hydrochloric acid, and then to follow up with potassium chlorate in the usual way. H. €€ B. S.

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DOI:10.1039/AN8992400011

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年代:1899

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THE ANALYST. 13 ORGANIC ANALYSIS. Detection and Estimation of Methyl Alcohol in Ethyl Alcohol. Trillat. ( A m et Rev. Chinz. AizaZyt., vol. iii. [9], pp. 294-300.) -The author finds that ethylal and niethylal are constantly formed amongst the products of the oxidation of ethyl alcohol, and that these furnish, when combined with dimethylaniline, bases diflering in properties. The base obtained from ethyl alcohol corresponds to the formula C,H,: 2[C,H4N : (GH3)J, and when dissolved in dilute acetic acid and treated with lead dioxide yields a blue solution, changi=lg immediately to green, afterwards to yellow, and becoming completely colourless when boiled. On the other hand, the base from methyl alcohol (CH, . [C,H4N : (CH3)J) gives a persistent blue coloration, which is rendered more intense by boiling, and enables 1 part of the base to be detected in 200,000 parts of solution.The same phenomenon is developed when the two alcohols are mixed, but in order to secure oxidation when the proportion of methyl alcohol is small, it is necessary to dilute the mixture with 10 volumes of water calculated to absolute alcohol, and it is advisable to employ 1.5 part of potassium dichromate to each part of absolute alcohol present. Another essential preliminary to the reaction is the careful rectification of the dimethylaniline to remove impurities, I n applying the test, 20 C.C. of the sample of alcohol are added to 300 C.C. of water and 30 grammes of powdered potassium dichromate, then cooled and mixed with 100 grammes of 20 per cent. sulphuric acid. After the reaction has proceeded for one hour the liquid is distilled, the first 50 C.C.(rich in acetaldehyde) being rejected. The distillate is neutralized with sodium carbonate and made up to 400 C.C. One-fourth of this is heated on a water-bath for five hours at 65" to 70" C. in a small closed flask, with 2 C.C. of rectified dimethylaniline and 1 C.C. of 10 per cent. sulphuric acid, with occasional agitation. After neutralizing with alkali and distilling off the excess of dimethylaniline, a, portion of the liquid is acidified with acetic acid, then treated with a few drops of water containing lead dioxide in suspension, and boiled in order to develop the blue coloration indicative of methyl alcohol. The coloration is compared in the usual manner with typical samples prepared beforehand, and is sufficiently decisive to detect 1 per cent. of methyl alcohol.When the latter exceeds 5 per cent., the base may be weighed direct. c. s. The Estimation of Caramel. Fradiss. (Bull. Ass. Chinz., 1898, xvi., 280.)- The substance under examination is mixed with methylic alcohol, which is evaporated on the water bath. The residue is dried first in vacuo, and then thoroughly in a,14 THE ANALYST. 0.9199 1.4687 110.4 197.5 0.83 aurrent of dry air. I t is then extracted for two hours under a reflux condenser with methylic alcohol (95 per cent.), which dissolves all the caramel. The filtered extract is mixed with an excess of amylic alcohol which precipitates the caramel, and the precipitate, after being dissolved and reprecipitated two or three times, is finally dried on a weighed filter at 90" C.Various samples of molasses examined by this method were found to contain from 1.10 to 2.50 per cent. of caramel. C. A. M. 0-9207 09208 1,4687 1 1.4681 109.1 1 107.9 197.0 ~ 198.1 0.57 i 0.68 The Characteristics of Curcas Oil. 0. Klein. (Zeit. angew. Chem., 1898, 1012-1015.)-The Jatropha Curcns, from the seeds of which this oil is obtained, grows to a height of 3 or 4 metres, and is cultivated in all the Portuguese colonies, but especially in the Cape Verde Islands, which supply about three-fourths of the total quantity shipped to Portugal. There are two factories where the oil is extracted in Lisbon, the finely-divided seeds being subjected to hot pressure. The oil is used for lubricating and lighting, and in the soap and candle manufactures, and the pressed residue fetches a high price for manure.The physical and chemical constants of the oil extracted in different ways by the author and of a commercial specimen were : ... .. . ... Specific gravity ... Refractive index at 25" C. Iodine value ... ... Saponification value . . . . Free acids ... 6 . . Volatile acids ... ... 109.8 203.5 4-96 1 Pressed. Pressed. , ! Hot -- 0.9240 1,4689 109.1 203.6 4.65 5.5 Extracted ~ Commercial. 'Old 1 with 1 Hot Pressed' Ether. ! Pressed. - I - I - The oil is of a yellowish-red colour, which varies in shade according to the degree of pressure and heat to which the seeds were subjected. It has a characteristic odour, which cannot be readily mistaken. The acetyl values of the hot-pressed and extracted oil were 34.7 and 51-7 respectively by Benedikt and Ulzer's original process.By Lewkowitsch's method (Journ. SOC. Chem. Ind.), the corresponding figures were 17.6 and 25.3. The melting-point of the fatty acids determined in a capillary tube was 29.5" to 30.5" C., and the solidifying point 25-75'' to 26.5". The oil is soluble in alcohol to the extent of 24.12 per cent. I t is insoluble in cold glacial acetic acid, but readily dissolves in the hot acid. The viscosity in Engler's apparatus at 20" C. was 9.45, so that in this respect curcas oil comes between crude rape-seed oil and olive oil, the latter having a viscosity of 9.03 to 10.3 (Kiinkler). The phytosterin determined by Bomer's method was 0-58 per cent. According to Hiepe (Rep.d. anal. Clzem., v., 22G), curcas oil is frequently used to adulterate olive oil in Portugal, but the author states that he has never yet met with any instance of such adulteration, although he has examined hundreds of suspicious samples of olive oil. Moreover, he considers such an admixture extremely improbable, taking into account the facts that 10 drops of curcas oil have a greater purgative effect than a tablespoonful of castor oil, and that an .addition of 10 per.THE ANALYST. . 15 cent. of curcas oil to olive oil imparts an unmistakable odour. For its detection in olive oil Hiepe recommends treating the oil with nitric acid and copper filings, the resulting elaidin being of a reddish-brown colour. The author confirms this, but shows that the reaction is not conclusive, since earth-nut and cotton-seed oils give a similar coloration.0 ther colour reactions are also inconclusive. I n Becchi's test; the commercial oil causes a slight reduction, but the fatty acids cause no reduction. I n the author's opinion the best tests for curcas oil in olive oil are the characteristic odour, and the increase in the specific gravity, refractive index, and iodine value. The oil was found to contain 9.59 per cent. of solid fatty acids melting at 57.5" C., and with a molecular equivalent of 269.5, from which data they were judged to consist of 20 per cent. of stearic and 80 per cent. of palmatic acid. No myristic acid could be detected. The liquid fatty acids (80 per cent.), separated as lead salts with ether, yielded on oxidation by Hazura's method equal quantities of sativic and dihydroxy-stearic acid, from which it was concluded that they consisted of equal parts of oleic and linolic acids.No ricinoleic or linolenic acid was found. C. A. M. __ -__ _ _ _ _ ~ _ _ _ -. Oil of Paradise Nuts, Oil of Brazil Buts, Maize Oil. G. de Negri. (C'hcm Zeit., 1898, xxii., 961, 976.)-Paradise nuts are the seeds of the Lecythis sapucnin (xabucajo), a large tree belonging to the MyrtaceB found in Brazil and Guiana. The seeds are edible, having a pleasant taste resembling Brazil nuts. On extraction with petroleum ether, 50 to 51 per cent. of a clear, colourless, or faintly yellow oil is obtained, which quickly turns rancid, but not so fast as oil of Brazil nuts. The latter begins to solidify at 4" or 5", and is quite solid at 0" ; oil of paradise nuts yields a white deposit at 12O, and solidifies completely at 8"; It is soluble in ether and chloroform, insoluble in cold absolute alcohol, hardly soluble in hot water; it is insoluble in cold acetic acid, but dissolves in an equal volume of the hot acid.When maize is ground the germs are usually removed, and the yield is about 1 per cent. They show the following composition : water, 11.55 per cent. ; nitro- genous matter, 39.07 per cent. ; fat, 12.5 per cent. ; carbohydrates, 31.76 per cent. ; mineral matter, 5.3 per cent. On extraction with petroleum spirit 8 per cent. of oil is obtained, which is clear, yellowish-brown, and possesses a characteristic odour. I t solidifies at 15" to a yellow crystalline mass.I t is soluble in ether, chloroform, and carbon disulphide, insoluble in cold absolute alcohol, soluble in 30 parts of hot spirit. It saponifies slowly with alcoholic,'potash. Maize oil quickly becomes rancid ; one sample kept for a year in a half-filled flask finally coritained 43-86 per cent. of free (oleic) acid. According to their place of origin, the germs differ widely in composition; one specimen of oil remained liquid at 0" for several hours ; the iodine and acid numbers also vary. I t s colour reactions are : Haydereich, orange-yellow with violef spots ; BrullB, black, afterwards blood-red, solid in twenty-four hours ; Schneider, no colour ; Becchi, very faint brown; Milliau, faint brown ; Baudoin, no colour. On distilling maize, a residue containing 11 per cent.of solid matter and 5.5 per cent. of oil is recovered (Villon). Maize itself yields 0.5 per cent. of oil, rather darker in colour than that obtained from the embryos. At 65" it dissolves in an equal volume of glacial acetic acid. The constants of these three oils are :16 THE ANALYST. Oil of Oil of Maize Oil. Brazil Nuts. Paradise Nuts. Specific gravity . . . ... ... 0.918 0.895 0.9245 Saponification number . . . ... 193.36 173.63 182.81 Iodine number . . . ... ... 106-22 71.64 115.17 Acid number (calculated as oleic) . , . 1.433 3-19 5.65 Solidifying point of fatty acids ... - 28.5" 29.7" Iodine number of fatty acids ... 106.04 72.33 123.27 Refractometer number at 15" (Zeiss- Solidifying point . . . ... . . I 0" 4" 15" ... - 44.08 c Acetyl number .. . I.. Melting point of fatty acids . . . 28"-30" 37.6" 39-5" Wollny) ... ... ... ... - 61 -3-6 1 -5 74.5 F. H. L. [Oil of paradise nuts must not be confused with oil of grains of paradise. Grains of paradise, guinea grains, or Melegueta pepper (Semina cardanzovzi majoris) are the seeds of Amomurn meleguetn, an African plant of the ginger species, This oil is volatile (cf. ANALYST, 1898, xxiii., 12). Paradise nute are also known as sapucaia nuts, or '' monkey pots."-F. H. L.] Henriques' Process for the Analysis of Indiarubber Articles. R. Thal. (Chenz. Zeit., 1898, xxii., 974.)-This process (Chem. Zeit., 1892, xvi., 1644) consists, i?zter d i n , in a separation of the true rubber from rubber substitutes by the action of boiling S per cent. alcoholic soda, filtering off the dissolved matter through paper to avoid contamination of the solution with particles of loosened loading material, etc.Thal observes that an error is introduced into the operation by the partial solubility of filter-paper in the reagent; and he finds that Schleicher and Schull's extracted papers '' No. 589," previously dried to constant weight at 100" C., lose between 4.86 and 6.88 (mean 5.63) per cent. of their weight when 100 C.C. of 8 per cent. alcoholic soda and the necessary amount of water to reniove alkalinity pass through them. Rubber goods which are not loaded and only lightly dusted with talc need not be actually filtered to separate the soluble from the insoluble portion ; but loaded articles must be filtered for the reasons just mentioned. He suggests, therefore, that the '' No.589 " papers 12.5 cm. in diameter be always employed, and that 5.5 per cent. of their weight be added to the extracted rubber residue as a correction for solubility ; taking 4 grammes of the sample for analysis, this loss, if not allowed for, would lead to a deficit of about 1-42 per cent. in the residue calculated on the crude material. F. H. L. Vanillin Mixed with Acetanilide. R. Hefelmann. (Apoth. Zed., 1898, No. 49 ; through Deutsche Chem. Zeit., 1898, xiii., 358.)-In this product (which has already been referred to, ANALYST, 1898, xxiii., 266) the acetanilide was detected by a nitrogen estimation. The adulterated vanillin began to melt at 61", instead of between 79" and 82". I t was only partially soluble in dilute caustic soda, whereas it should have been easily and completely soluble, To isolate the impurity, an ethereal solution was repeatedly extracted with strong sodium bisulphite, when the vanillin passed entirely into the aqueous liquid in combination with the bisulphite ; the ether was washed in a little water and evaporated. The residue exhibited the correct crystalline form, melted at 111" to 113", yielded drops of aniline on warming withTHE ANALYST. 17 concentrated potash, and gave a strong odour of isonitrile on addition of chloroform to the alkaline liquid. Acetic acid was also to be recognised by the ordinary tests. F. H. L.

ISSN:0003-2654    

DOI:10.1039/AN8992400013

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年代:1899

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THE ANALYST. 17 INORGANIC ANALYSIS. The Assay of Telluride Gold Ores. C. H. Fulton. (School of Miizes QzmrterZy, 1898, xix., 419-426.)--From the results of a series of experiments on the assay of gold ores containing tellurium, the author has come to the following con- clusions: In order to obtain good results, it is essential to have a large excess of litharge, but in the case of rich telluride ores this should be obtained by reducing the amount of ore, rather than by increasing the litharge, since otherwise the lead button may be too large to cupel directly. I n the crucible assay, with direct cupel- lation, which is considered the best, the fire should be moderately hot, and the length of time in the furnace should be from forty to fifty minutes. The assay should be conducted so as to give a button of good size (from 20 to 28 grammes).The cupella- tion should be made at a low heat with crystals of litharge forming on the cupel, and in accurate assays the crucible slag should be Te-melted, the button cupelled, and the amount of gold added to the first assay. Scorification of any kind leads to bad results with telluride ores, and the loss of gold on cupelling a large or brittle button directly is much less than if it were first rescorified. The amount of gold lost in the slag on scorifying directly is very great, amounting to as much as 5-6 per cent. in the assays described. The loss of gold in a rich telluride ore is greater than in a, low-grade ore, but the percentage of loss decreases with the richness of the ore. These conclusions agree with the experience of F.C. Smith, who found that the loss of gold in the assay of ores containing tellurium was very great, if the charge was not prepared with the correct proportion of litharge. C. A. M. Separation of Zinc, Copper, Mercury, or Bismuth from Aluminium. F. S. Havens. (Zeits. aizorg. Chenz., 1898, xviii., 147.)-The process which the author has already described (ANALYST, xxii., 194, and xxiii., 109) for the precipitation of aluminium chloride in presence of ether and hydrochloric acid, is equally available for the removal of the other metals mentioned in the title. The residual zinc chloride is preferably converted into nitrate by repeated evaporations with nitric acid, then ignited in a platinum crucible and weighed as oxide. Copper is converted into sulphate, rather than nitrate, and also weighed as oxide.The figures recorded by the author in two tables are highly satisfactory, showing maximum errors of - 1.3 and + 0.9 milligrammes in estimating about 0-5 gramme of alumina ; - 0.8 and + 0.4 milligrammes (corrected) in the direct estimation of the accompanying zinc oxide (0.1 to 0.2 gramme) ; and - 0.7 and + 1.3 rnilligrammes in the case of copper oxide; while all the mean results are practically identical with those demanded by the theoretical composition of the several mixtures analysed. F. H. L.18 THE ANALYST, Analysis of Ferro-Tungsten. A. G. McKenne. (Proc. Eng. Xoc. IVestern Peunsylvania, 1898, xiv., 171.)-0*5 gramnie of the finely-powdered sample is mixed with 3 grammes of sodium peroxide in a copper* crucible, and the mass is raised for a minute to a dull-red heat, holding the crucible in tongs so as to agitate its contents and prevent the alloy from sinking to the bottom.The melt is extracted with water, a few C.C. of alcohol added to render manganese insoluble, and the whole filtered. The filtrate, containing the tungsten and part of the silica, is evaporated to dryness twice with hydrochloric acid, taken up in weak HCI, boiled, filtered, and the residue washed with 1 : 10 nitric acid (water would cause it to pass through the paper). The insoluble matter from the fusion, which contains the iron, manganese, copper, and some of the silica, is dissolved in hot dilute nitric acid and evaporated to dryness. It is dissolved in weak HCl, and the silica is collected on the same filter that already holds the tungsten, washing as before with nitric acid.The combined precipitate is ignited and weighed as WO,+SiO,; then treated with 0.5 C.C. of sulphuric and 5 C.C. of hydrofluoric acid to volatilize the latter in the usual way. The iron and manganese are subsequently separated. I n the presence of chromium and aluminium, the filtrate from the tungsten should be precipitated with ammonia, the mixed oxides weighed together, dissolved in strong nitric acid and potassium chlorate, and the alumina thrown down alone by a small excess of ammonia. After adding nitric acid, the chromium in solution can be titrated with ferrous sulphate and permanganate, or reduced with peroxide and weighed as Cr,O,. Part of the aluminium will be found in the iron precipitate, and must be allowed for, Carbon may be conveniently estimated by the same process, for it is entirely converted into sodium carbonate, which can be decomposed with acid, absorbing the gas in barium hydrate.Corrections must be made for the several impurities, car- bonate, silica, and iron, in the sodium peroxide, for which reason a known amount must always be used. F. H. L. Estimation of Molybdenum. H. Brearley. (Chem. News, 1898, Ixxviii., 203.) -The author has investigated Chatard’s gravimetric process, which depends on the precipitation of sodium molybdate with lead acetate ; and also Schindler’s volumetric method of titrating an acidified solution of a molybdate with lead acetate, using tannin as an external indicator.To the former, various limitations were ascribed by Fresenius and by Chatard himself ; but the present experiments widen its range of usefulness and bring out the following points : It is not necessary to employ neutral solutions; some free acetic acid is advantageous, as it obviates any danger of precipitating lead if faint alkalinity has been overlooked. Two C.C. of 33 per cent. acid may safely be used when dealing with 0.1 gramme of molybdenum; but an excess tends to change the molybdate from a granular to a powdery nature, and * The author finds that copper resists the action uf sodium peroxide quite as well as nickel, while adventitious salts of the former metal are less troublesome iri the course of an analysis,THE ANALYST. 19 renders it liable to pass through the filter.This may be overcome by washing with a mixture of 1 C.C. of .lead acetate solution (7.896 grammes per litre) and 500 C.C. of water just acidified with acetic acid. It is not necessary to separate the precipitate from the prtper before ignition; they can be burnt together, wet or dry, in a muffle. It is advisable, however, to carbonize the paper at the lowest possible temperature, because extreme heating to remove refractory carbon is disallowed by the instability of the lead molybdate. The precipitate is not reduced nor appreciably altered in weight by ignition in presence of carbcn. It can be safely ignited at a moderate red heat; even at full redness, or the melting-point of sodium carbonate, it only loses about 1 per cent.in six hours. The chlorides and nitrates of sodium and ammonium do not affect the process; ammonium acetate, as made by neutralizing 0.880 ammonia with 33 per cent. acid, in large amounts simply involves a second filtration of the precipitate. It does not appear to retain alkaline salts, and prolonged washing is therefore unnecessary. If the ignited precipitate is dissolved in hydrochloric acid, neutralized with ammonia, treated with excess of acetic acid and a little more lead acetate, the purified molyb- date is never sensibly different in weight. Manganese, copper, cobalt, nickel, zinc, magnesium, and mercury (ic) exert no practical interference, and occasion no trouble beyond more careful washing or a reprecipitation of the ignited molybdate. Even the unpurified precipitate carries down with it but little of these metals; and their presence can generally be detected by a variation from the normal (creamy) colour of the product.Zinc molybdate is mostly dissolved by the usual excess of acetic acid; if only an opalescence remains, it may be neglected; if the liquid is distinctly cloudy, the free hydrochloric acid of the original molybdenum and zinc solution must be partly replaced by acetic. I n presence of mercury, the liquid must be warmed or ammonium acetate added. Uranium contaminates the molybdate of lead more seriously ; by one reprecipitation the error may be reduced to 0.5 per cent. ; but repeated operations are needed to separate the last traces. Schindler’s volumetric process is quicker and gives equally correct results with pure alkaline molybdates; but as the end of the titration is approached, the colour The method may be made more accurate by employing the tannin indicator as long as it is available (generally this is to within 1 per cent.of the truth), then filtering off a little of the hot liquid and testing it with lead acetate and sodium molybdate; more of the necessary reagent is added to the bulk, and the test is repeated with the same filter until the titration is complete, The influence of other metallic salts has not been investigated. The reaction between lead acetate and molybdenum is so delicate that in a solution faintly, but decidedly, acid with acetic acid, 1 part of molybdenum in 4 million produces a distinct cloudiness. Cobalt requires a second precipitation.eaction between the molybdate and the tannin becomes rather uncertain. F. H. L. The Analysis of Commercial Chrome Yellow. Willenz. (Bull. de Z’Ass. beZge., 1898, xii., 163-167.)-The author’s objection to Wittstein’s method of examining chrome yellow (Dingl. polyt. JOUT., ccx., 280) is that the lead chromate is not20 TEE ANALYST. completely decomposed by the digestion with sodium carbonate, and hence the residue cannot be correctly taken as barium sulphate. He has found, in fact, that the residue from pure lead chromate may amount to as much as 49 per cent. One gramme of the powdered material is digested with 100 C.C. of dilute hydrochloric acid (1.20) at a gentle heat, and the residue transferred to a filter and washed with hot water. The total calcium in the filtrate is precipitated as oxalate, the calcium present in the form of sulphate calculated from a determination of the sulphuric acid, and the calcium in the form of carbonate obtained by difference.The lead sulphate is determined by digesting the residue with 50 C.C. of a neutral or slightly alkaline solution of ammonium acetate (specific gravity, 1-04), filtering, and evaporating the filtrate to dryness with an excess of sulphuric acid. After the addition of 50 C.C. of water, the residue is boiled for about ten minutes with 25 C.C. of a solution of potassium hydroxide, containing 112 grammes of KOH per litre. This converts the lead chromate into potassium plumbite, which dissolves, leaving behind the barium sulphate and clay. A separate estimation of the amount of chromic acid is made by Bunsen’s iodometric method.C. A. M. The following method is recommended as giving satisfactory results. The Analysis of Incandescence Mantles. E. Hintz and W. Weber. (Zeit. anal. Chern., 1898, xxxvii., 94-111.)-The mantles which have come under the authors’ notice during the last three years have been composed almost without exception of thoria (96.42 to 99.26 per cent.) and ceria (0.49 to 2-02 per cent.), whilst the other rare earths, neodymia, lanthana, yttria, and zirconia, have only been present in minute quantities. Lime (0.1 to 1-05) and magnesia (trace to 0.21) were almost invariably present, and in some cases traces of silica. With the object of determining whether these minor constituents had any influence on the light-emitting properties of the mantles, one of the authors (Hintz) has made a series of photometric experiments, from which he has arrived at the following conclusions : 1.Zirconia, lanthana, and yttria added in small quantities up to 1 per cent. do not increase the illuminating capacity of pure thoria mantles, but, on the contrary, tend to lower it. A very small addition of neodymia is also without much effect, but when the amount reaches 1 per cent. there,is a slight increase in the quantity of light emitted. 2. The addition of neodymia, lanthana, or yttria (up to I per cent.) to mantles composed of thoria (99 per cent.) and ceria (I per cent.) does not increase their illuminating power. Similarly, an addition of from 0.2 to 1 per cent. of zirconia has no effect, but the influence of 0.1 per cent.is doubtful. 3. An addition of zirconia, neodymia, lanthana, or yttria (up to 1 per cent.} to thoria-ceria mantles containing 0.5 per cent. of lime is without effect. The authors have examined Knorre’s volumetric method of determining ceria (ANALYST, this vol., 191), and find that the results thus obtained are as reliable as those of the gravimetric method. For the volumetric estimation of ceria in theTHE ANALYST. 21 quantity in which it occurs in mantles they proceed as foIlows : 100 C.C. of the solution containing about 1 gramme of thoria and 0.1 gramme of ceria are acidified with from 5 to 7.5 C.C. of dilute sulphuric acid (1 : 6), diluted to 200 c.c., and the cerium compounds oxidized into the ceric state by adding three small successive portions of ammonium persulphate in the cold, and then boiling for one or two minutes after the first two additions, and finally for from ten to fifteen minutes after the final addition (about 3 grammes of persulphate are required to oxidize 0.2 to 0.3 gramme of cerium).At the conclusion of the boiling an additional 2 C.C. of the dilute sulphuric acid is added. When completely cold a dilute solution of hydrogen peroxide is run in, and the liquid rapidly titrated with potassium permanganate. The authors recommend the following simplified method for the analysis of unburnt mantles. A number of the stockings-not less than twelve-are weighed, and their upper and lower ends cut off, since the former are often dipped in a hardening solution, and the latter into a solution of a, ceriuin salt, in order to make the total percentage of ceria appear higher. The middle portions are weighed and completely extracted with water containing a few drops of nitric acid.The fabric remaining is ignited, the ash fused with potassium bisulphate, the melt dissolved in water containing hydrochloric acid, ammonia added, the precipitate dissolved in nitric acid, arid the solution added to the main solution, which is then made up to definite volume. 1. Neodymia is tested for spectroscopically in a portion of the concentrated solution. 2. An aliquot portion is treated with oxalic acid after removal of the free acid by evaporation. a. The precipitate is collected on a toughened filter, washed, and tested for neodymia, lanthana, and yttria as follows : The precipitate is washed into a beaker, heated with a concentrated solution of ainmonium oxalate, the liquid diluted, allowed to cool, and filtered after standing for a long time.As the authors have shown in a former communication (ANALYST, this vol., Sl), the residue left after extraction with ammonium oxalate contains a little thorium oxalate, so that even in the absence of neodymia, yttria, and lanthana, the percentage of ceria obtained will be higher than the truth, If, however, the amount calculated from the weight of the precipitate does not exceed that of the actual quantity of cerium present by more than 1 per cent., it may be at once concluded that neodymia, lanthana, and yttria are not present in sufficient quantity to affect the illuminating capacity.If, on the other hand, the excess is more than 1 per cent., a further examination is required. The weighed precipitate is dissolved by heating with sulphuric acid in a platinum crucible and the solution tested for these earths, b. The filtrate from n is evaporated to dryness, the residue gently ignited, dissolved in hydrochloric acid, the excess of acid removed by evaporation, and the zirconia tested for microchemically by evaporating a drop of the solution on the object-glass after the addition of a drop of a solution of potassium binoxalate. I n the presence of as little as 0.1 per cent. of zirconia characteristic crystals of potassium zirconium oxalate are to be observed. The presence of lime has also an influence on the result.22 THE ANALYST, 3.An aliquot portion of the solution after removal of the free acid is precipi- tated with oxalic acid, and the precipitate, consisting of the total rare earths excepting zirconia, ignited and weighed. Lime has an influence on the result, but for practical purposes the authors consider that it is not of great importance if, in a mantle containing, say, 98.4 per cent. of thoria, and 1.2 per cent. of ceria, 0.4 per cent. of lime is calculated with the thoria (= 98% per cent.). 4. The ceria is determined volumetrically in another aliquot part of the solution. The result deducted from that obtained in (3) gives the amount of thoria, provided that not more than negligible quantities of neodymia, lanthana, and yttria are present. C. A. M. Estimat,ion of Carbon i n Iron by Combustion.Rozycki. ( M o d . Scient., 1898, [4], xii., 636; through Chem. Zeit. Rep., 1898, 254.)-2*3 grammes of steel, or 0.25 gramme of ferrochrome, in fine powder, are mixed with 20 grammes of pure alumina, placed in a boat inside a combustion-tube 60 em. long, and ignited in a current of pure oxygen. The gas is led over red-hot copper oxide, and finally absorbed in baryta water. The baryta is decomposed with nitric acid in Wiborgh’s apparatus, and the carbon dioxide measured. The combustion occupies thirty-five minutes with steel, 1+ hours with ferrochrome. F. H. L. A Reaction of Metallic Sulphides soluble in Ammonium Sulphide. J. Ducommun. (Schzceix. ~ ~ o c h . Pharm., 1898, 434 ; through Deutsche Chem. Zeit., 1898, xiii., 346.)-When yellow ammonium sulphide is mixed with a small quantity of formaldehyde, the colour disappears, and after a short time a copious white preci- pitate is thrown down, which is entirely soluble in strong sulphuric acid. If the sulphide is first diluted till it is only faintly yellow, formaldehyde produces no precipitate, and the liquid remains perfectly clear.I n the presence of arsenious sulphide, the solution is bleached by the formalin, while sulphuric acid yields a white precipitate insoluble in excess. Antimony gives an orange-red precipitate on addition of acid; stannous or stannic sulphide, a, white; gold, a yellowish-white; platinum, a brownish-red ; the latter metal also prevents the previous decolorization. The precipitates are evidently some organic compound of the respective metals, for they turn black on ignition.I n all cases the liquids should be cold and highly dilute; and then the reaction is capable of detecting 2 milligrammes of arsenious acid, and somewhat more of either gold or platinurn. Arsenic acid only behaves in a similar fashion after it has be,en reduced by boiling the ammonium sulphide. The process may be employed in the course of ordinary qualihtive analysis to avoid the u6e of sulphuretted hydrogen. The solution containing various metals is neutralized with ammonia, treated with ammonium sulphide, and boiled to dissolve platinum and reduce arsenic compounds. One part of the filtrate is diluted and mixed with formaldehyde and acid. If a precipitate is produced, the remainder of the filtrate is analysed in the regular way ; but if no precipitate is formed, arsenic, antimony, and tin are absent, and the first sulphide precipitate, together with the inother liquor, is concentrated slightly, and boiled with strong hydrochloric acid in order to separate the mixture into a solution containing those metals whose sulphidesTHE ANALYST.23 are acid-soluble and a residue of the heavy metals, such as copper, etc., which yield insoluble sulphides ; these are then severally examined as may be necessary. The reaction shows that many sulphides, usually considered to be insoluble in ammonium sulphide, are really a trifle soluble therein-viz., copper, iron, lead, mercury. It should also be useful for detecting arsenic in pharmaceutical prepara- tions like bismuth subnitrate. F.H. L. Estimation of Sulphides, Sulphites, and Thioaulphates. W. Feld. (Chem. Industrie, ‘‘ 17J1898 ”; through Dezitsche Chem. Zeit., 1898, xiii., 322.)-The funda- mental reactions underlying the author’s processes are as follow : (1) Sulphides of the alkalis and alkaline earths, whether dissolved or suspended in water, are decom- posed by tt strong solution of magnesium chloride, forming sulphydrate and hydroxide, which are broken up on boiling in a, current of carbon dioxide into magnesium carbonate and sulphuretted hydrogen. The latter is absorbed in standard iodine. (2) Sulphites yield the theoretical amount of sulphurous acid on distillation with hydrochloric acid, and the gas is also absorbed by iodine. Thiosulphates cannot be estimated in this way, for on heating with hydrochloric acid they produce sulphuretted hydrogen and sulphurous acid, with the deposition of free sulphur.(3) But if a thiosulphate is treated with iodine, it is converted into tetrathionate, and the latter distilled with HC1 in presence of aluminium is reduced to H,S, which can be deter- mined in standard iodine as before. Any sulphite preRent at the same time is oxidized at once to sulphate, and takes no further part in the operation. (4) Thio- sulphates are decomposed by mercuric chloride, yielding mercuric sulphide and a sulphate. Sulphites are not attacked, so that they can be boiled with HCL, and the SO, absorbed as before. Excess of mercuric chloride is advantageous, and it may be employed in the solid state. An Erlenmeyer flask, holding 300 to 350 c.c., is fitted with a rubber cork having two holes.Through one is introduced a stoppered tube-funnel reaching to the bottom of the vessel; its upper opening can be closed with a cork bearing a, bent tube connected to a supply of pure carbon dioxide (conveniently a cylinder of liquid). Through the second hole of the main cork is passed a short tube joined to four Geissler’s potash bulbs, the ends of the several pieces of apparatus being made to touch within the rubber connecting tubes. The last set of bulbs is joined to a 10-litre aspirator to maintain and regulate the carrent of gas, and to measure roughly the volume passed. The first bulbs are empty, serving as water-condensers; the second are charged with a sufficiency (5 to 40 c.c.) of decinormal iodine to absorb all the gas evolved; the third contain some more (2 to 15 c.c.), diluted if necessary with water ; the fourth are filled with 5 or 10 C.C.of decinormal thiosulphate to catch m y volatilized iodine. To analyse a mixture of sulphide, sulphite, and thiosulphate, the sample in solution or fine powder mixed with water is brought into the flask, the cock on the funnel closed, and the whole apparatus tested for leaks. If satisfactory, the funnel tube is raised out of the liquid, and about 1 litre of CO, is passed to drive out air (were this precaution omitted, part of the H,S might be oxidized to free S, which, however, would be noticed in the empty bulbs). Twenty C.C. of a 25 per cent.24 THE ANALYST. solution of magnesium chloride (specific gravihy, 1.22) are run in through the funnel without admitting air, the tube is pushed down again to the bottom of the flask, the liquid is heated, and the gas turned on at such a speed that the aspirator is emptied in about forty-five minutes.The pozash bulbs are then rinsed out and titrated, 1 C.C. of +"Ti iodine being equal to 0*00895 gramme of B a s or to 0.0039 gramme of Na,S. The bulbs are charged once more, mercuric chloride and hydrochloric acid added to the contents of the flask, and the whole distilled again; the amount of iodine consumed represents the sulphite, 1 C.C. being equal to 0.0063 gramme of Na,SO,. A fresh portion of the original sample is titrated with & iodine till it turns blue (the quantity used need not be noted); the mixture is placed in the same flask, together with rolls of thin pure aluminium foil which partly project above the liquid, acid is added, the gas turned on, and finally the solution is gently warmed ; this gives the thiosulphate; 1 C.C.of iodine is equal to 0,00395 gramme of Na,S20,. I t is highly desirable to check the purity of the several reagents employed through- out the process, lest reducing gases be produced among them. F. H. L. Direct Conversion of Potassium Iodide and Bromide into Chloride. F. W. Kuster. (Zeits. anorg. Chenz., 1898, xviii., 77.)-Dry potassium iodide can be safely and quantitatively converted into chloride by ignition in a stream of chlorine at a moderate temperature, heating it (about 2-5 grammes) for half an hour in a, porcelain crucible over a luminous gas-flame about 2 cm.high, the top of which is kept 3 cm. from the base of the vessel. Even if the temperature be raised for a time till the crucible begins to glow, the loss is very minute (0.3 milligramme), and it is doubtful whether this is actually caused by volatilization of chloride. Dry potassium bromide cannot be decomposed in this manner; but if the sample be moistened, a similar reaction takes place more slowly, and by the following modification becomes equally available for analytical purposes. 2.5 grammes of the bromide are brought into an Erlenmeyer flask 7 cm. in height, together with 1 C.C. of water and 1 drop of 10 per cent. hydrochloric acid; and a current of chlorine is admitted through the porcelain tube of a Rose's crucible.The flask is placed on a sheet of asbestos, with a second sheet 2 cm. beneath, on which plays a small pilot gas-flame. The temperature is raised till the bromine evaporates quickly without boiling. After an hour or an hour and a half, one of the asbestos shields is removed and the water driven off ; then the heat is gradually increased until the remaining asbestos is visibly red. The whole operation is repeated once or twice to obtain constant weight ; but if a smaller quantity of bromide is taken in the first instance, the reaction is often complete the first time. The result may be most simply calculated by the use of the formula 9' %KBr = a + b- 9 where a= 267.59 ; b = - 267.59 ; g' the weight of the potassium chloride ; g that of the original bromide.The examples quoted by the author show yields of 100.00 and 100*01 per cent. when working on pure potassium iodide. A specimen of Kahlbaum's bromide gaveTHE ANALYST. 25 99.07 and 99.08 per cent. of KBr by the above method; 99-06 and 99.20 per cent. by ignition of the silver halide in chlorine (calculating from the potassium bromide itself); 99.16 and 99.10 per cent. by similar treatment (calculating from the silver compound}. Commercial iodide seldom contains any impurity except water ; bromide contains nothing except moisture and chloride. F. H. L. Volumetric Estimation of Combined Sulphuric Acid. M, Reuter. (Chenz. Zeit., 1898, xxii., 357.)-The author has submitted Andrews' method for the titration of sulphate solutions to a careful examination ; and he finds, provided the operation is carried out exactly in the following manner, that its accuracy, speed, and simplicity leave nothing to be desired.10 C.C. of the original solution, which should contain about 0.14 gramme of anhydrous sodium sulphate, are boiled with 150 C.C. of a solution of barium chromate prepared by dissolving 3 or 4 grammes of pure precipitated chromate in 1 litre of water by the aid of 30 C.C. of strong hydro- chloric acid. The acid is neutralized with powdered chalk, and the precipitate filtered off and washed; the filtrate is thoroughly cooled, acidified with 5 C.C. (not more) of strong HC1, treated with 20 C.C. of a 10 per cent. solution of potassium iodide, allowed to rest for five minutes in a covered vessel and an atmosphere of carbon dioxide (to give time for the complete reduction of the chromic acid, yet to prevent oxidation of the HI), then diluted to 1 or 14 litre, and finally titrated with decinormal thiosulphate.Three atoms of iodine correspond to one molecule of sulphuric anhydride, F. H. L. Method of Preparing an Exactly Neutral Ammonium Citrate Solution. A. D. Cook. (Jozir. Anzer. Chem. SOC., 1898, xx., 585-586.)-1t has been stated by several chemists that an exactly neutral ammonium citrate solution for agricultural analysis may be obtained by allowing the solution to stand after ammonia has been added to the citric acid and the proper dilution made. The author, however,-finds that this is only the case when the solution has a sufficient temperature to expel the excess of ammonia.By vigorous stirring sufficient heat for the purpose is caused by the chemical action, but if this is neglected the solution will be slightly alkaline. The method recommended for the preparation of the reagent is its follows: 740 grammes of commercial [citric acid are mixed with 1,900 C.C. of 10 per cent. ammonium hydroxide. After vigorously stirring the liquid until the acid has all dissolved, the solution is made up to 4,000 C.C. with water. I t is then again stirred and transferred to a large evaqorating dish, where it is allowed to stand over-night. Finally, it is transferred to the reagent bottle, brought to 20" C., and water added until the specific gravity is 1.09. C. A. M. Estimation of '' Available " Phosphoric Acid in Thomas Slag. J. Freund- lich. (Chem.Zeit., 1898, xxii., 974.)-Wagner has lately shown (ANALYST, 1897, xxii., 334) that in slags containing much silica, this substance may be prevented from contaminating the precipitate of ammonium magnesium phosphate, if the freshly26 THE ANALYST. prepared citrate extract be treated with magnesia mixture previously mixed with alkaline citrate solution. Many slags, however, also contain sulphide of iron and calcium ; and these bodies, being decomposed by the citric acid, yield sulphuretted hydrogen, which does not entirely escape, but, combining with the ammonia sfter- wards added, precipitates the iron once more, producing a blackish phosphate that becomes red on ignition. To avoid this error, a, second precipitation should be resorted to whenever the slags contain much sulphur ; and the ferrous sulphide in the first precipitate should be oxidized with nitric acid or aqua regia.F. H. L. Estimation of Perchlorate in Chili Saltpetre. 0. Foerster. (Chem. Zeit., 1898, xxii., 357.)-The ordinary method of reducing the chlorates and perchlorates in commercial sodium nitrate by heating the mass to a red heat has several disadvan- tages If the temperature be too low, they are not completely decomposed ; while on the other hand, chlorine is apt to be lost by volatilization of the sodium chloride. The author’s process is very exact, and does not demand the use of any particular degree of heat. 10 grammes of the sample are mixed with an equal weight of dry sodium carbonate (free from chlorine), and the whole is heated in a covered platinum or capacious porcelain crucible over a large flame for about ten minutes, till the mass is in tranquil fusion and no more bubbles of gas are given off.The melt does not creep up the walls of the vessel, and it is readily soluble. It is finally dissolved in excess of nitric acid, and the total chlorine is determined as usual. F. H. L. (Cf. Abstract, ANALYST, xix. 221.) Estimation of Perchlorate in Saltpetres. N. Blattner and J. Brasseur. (Chem. Zeit., 1898, xxii., 589.)-Five or ten grarnmes of the dried potassium or sodium nitrate are heated for fifteen minutes over a Btinsen flame with 8 or 15 grammes of calcium oxide, carbonate, or preferably hydroxide. The mass is dissolved in pure nitric acid, the total chlorine determined by any of the usual methods, and deducted from that already existing as chloride in the original sample.The process is more convenient than those in which alkali-metal carbonates are employed, because the mixture does not melt, and thus is more readily soluble, while there is no danger of loss by volatilization, etc. I n three different ship-loads of refined ” Chili saltpetre, supposed to contain at least 96 per cent. of sodium nitrate and less than 1 per cent. of sodium chloride, ‘the authors discovered from 0.12 to 1-01 per cent. of NaC1, and from 0-42 to 0-77 per cent. of NaClO, ; while a sample of potassium nitrate, ( ( pure for analysis,’’ contained 0.47 per cent. of perchlorate, but no chloride. F. H. L. (C’. ANALYST, xix., 221.) Microscopic Detection of Perchlorate in Chili Saltpetre.M. van Breuke- leveen. (Rec. trav. chim. des Pays-Bas, 1898; xvii., 94 ; through Chem. Zeit. Rep., 1898, 145.)-Behrens’ test for a perchlorate, which depends on the recognition under the microscope of the rhombic and almost insoluble crystals of rubidium perchlorate, can only be used in the examination of sodium nitrate when the impurity (calculatedTHE ANALYST. 27 as potassium perchlorate) amounts to at least 0.6 per cent. To detect smaller quantities (0.2 to 0.6 per cent.) 10 grammes of the sample are dissolved in 10 C.C. of hot water, diluted with 50 C.C. of 95 per cent. alcohol, raised to the boiling-point, and allowed to cool for one or two hours. The clear liquid is then poured off, evaporated to dryness on the water-bath, the residue taken up in as little water as possible, and Behrens’ test applied.If the rubidium salt is coloured with permanganate, only enough of the latter must be added to give the liquid a faint pink tint when it is placed on the microscope slide and held over a sheet of white paper ; or crystals of rubidium permanganate may be mistaken for those of the perchlorate. F. H. L. - _ _ _ _ _ _ _ _ ~ ~ A False Nitrous Acid Reaction in a Drinking Water. A. Bomer. (.&it. fiir Untersuch. der Nahr. uitd Geizussmittel, 1898, 401.)-The attention of the directors of a waterworks having been called to a strong nitrous acid reaction given by the water, the matter was referred to the author for report. The addition of zinc iodide and starch and sulphuric acid certainly produced a deep blue colour, On careful examination, however, the water was found to contain some suspended matter which proved to be manganic dioxide, the presence of which, in conjunction with the chlorides in the water and the added sulphuric acid, would be sufficient to account for the reaction. After separating the suspended matter from the water the reaction was not produced. A short time afterwards the author received from the same company €or examin- ation a piece of lead pipe containing a, brownish-black incrustation, which proved upon analysis to consist principally of oxides of manganese. H. H. B. S. The Advantage of using ‘( Normal Volumes ” in Analysis. M. Monhaupt. (Che7.lt. Zeit., 1898, xxii., 806.)-In the ordinary routine work of a laboratory, it is customary to weigh out such a quantity of the substance under examination that the final figures (weights, volumes, etc.) shall give at once the percentage of the ingredient sought ; the author pleads that the same device should be adopted when the sample is measured at the commencement of the test. For instance, in the potash trade, where determination of the proportion of potassium chloride in raw products, etc., is constantly required, the original (‘I normal ”) weight is always a multiple of 0.3056 gramme-the factor which converts K,PtCI, into KC1-and the final weight multiplied by 100 is the percentage desired. Similarly, when the analysis has to be conducted on a liquid, 30.56 C.C. (the ‘‘ normal volume ”) may advantageously be measured in a special pipette, and tedious calculation be avoided here also. F. H. L.

ISSN:0003-2654    

DOI:10.1039/AN8992400017

出版商:RSC    

年代:1899

数据来源: RSC

摘要:

THE ANALYST. 27 APPARATUS. Apparatus for the repeated Extraction of Liquids with Immiscible Solvents. (Ckem. Zeit., 1898, xxii., 868.)-The idea of this apparatus is to avoid the loss of material which often accompanies the use of a separating T. Posner.28 THE ANALYST. funnel when a solution has to be extracted more than once with the same liquid. It is essentially a combination of two separating-funnels joined together by means of the stop-cock p. The plug of the latter has two passages lying in the same plane : one serves to place A and B in connection, the other simultaneously allows the air in B to escape-the bulb shown in the enlarged section being intended to catch any splashes. The liquid to be extracted is placed in A ; if the solvent is specifically heavier, it is simply run off into B, which acts as a reservoir, while a fresh portion is brought into A and agitated once more.When the solvent is lighter than the liquid, extraction takes place in A , the aqueous portion is passed into E, A is emptied into a beaker or flask, the whole apparatus is inverted, and the liquid run back into A for treatment again. To prevent mistakes one end of the crutch handle of ,B is made of coloured glass. F. H. L. Apparatus for Determining the Consistency of Grease and Similar Articles. R. Kissling. (Chem. Zeit., 1898, xxii., 867.)-This is an improved form of the apparatus originally devised for estimating the viscosity of a grease by noting the W time occupied by a weighted rod to sink into the mass. A is an aluminium'rod weighing exactly 50 grammes, 300 mm.long, 9 mm. in diameter, and tapered from a point 55 mm. above its lower extremity to its end. ab is an X-shaped plate of brass fastened to the rod, having a pin t, on which three annular weights of 50, 100, and 200 grammes respectively can be dropped ; s is a stop that at the end of the test rests upon W. gh is a glass tube 150 mm. long and 9-5 mm. in internal diameter, supported vertically by the metal ring TV. C is filled with the material under examination to a height of 120 mm. When making a test, it is desirable so to arrange the apparatus that the rod shall fall in between 10 and 60 seconds ; if this be done, by adding the number of seconds to the total weight of A (irduding the brass weights, if one or more be employed), a '( consistency number " is ___. - given directly. But whenever the period of fall exceeds 100 seconds, if the weight of A is 50 8 Q ~- graninies the number of seconds must be divided by ten, and if the weight is 100 grammes divided by two before adding the time to the weight. I n this manner greases and gelatinous preparations can be valued simply and with fair accuracy, for the apparatus is capable of differentiating such bodies according to their viscosity into materials having " consistency numbers " ranging between 94 and 405. F. H. L.

ISSN:0003-2654    

DOI:10.1039/AN8992400027

出版商:RSC    

年代:1899

数据来源: RSC

摘要:

THE ANALYST. FEBRUARY, 1899. PROCEEDINGS OF THE SOCIETY OF PUBLIC ANALYSTS. AN extraordinary general meeting was held on Wednesday, January 4, 1899, in the Rooms of the Chemical Society, Burlington House, Piccadilly, for the purpose of amending the constitution and rules of the Society. The President (Dr. Dyer), who occupied the chair, explained the amendments sug- gested by the council, which, in addition to minor alterations, included a re-modelling of the conditions under which candidates might apply for admission to the membership of the Society. The chief amendment in the rule bearing upon this point was in the omission of the hitherto existing provision that candidates for membership should be analysts in actual practice, a qualification which it had always been difficult to define, and one which it had been frequently necessary to interpret with some degree of elastioity.Notwithstanding this, the rule had formed a technical barrier to the inclusion within the ranks of the Society of a number of qualified analysts who other- wise would have been glad to join the ranks of the Society. The council believed that the new and wider definition would, by removing this difficulty, be advan- tageous to the Society, as well as to the profession from the ranks of which its members were drawn. The adoption of this new definition of qualification would render the existence of the class of associates, viz., assistants to analysts in actual pmctice, no longer necessary, and it was therefore proposed that the Society should not in future include associates.The present associates who had attained the age of twenty-one would at once be eligible for admission to full membership by election in the usual way, while the remainder, whose number, he believed, was but very small, would become eligible on reaching that age. After a, discussion, in which Messrs. A. E. Ekins, E. W. Voelcker, S. Rideai, E. J. Bevan, H. Droop Richmond, C. H. Cribb, and Leo Taylor took part, the new constitution and rules were unanimously adopted, on the motion of the President, seconded by Mr. A. E. Ekins. - _ _ _ _ The monthly ordinary meeting of the Society was held on Wednesday, January 4, 1899, after the extraordinary meeting, the President (Dr. Dyer) being in the chair. The minutes of the previous ordinary meeting were read and confirmed. Mr. F. C. J. Bird, analyst to Messrs. C. W Harker, S t a g and Morgan, London,30 THE ANALYST. and Mr. J. H. Heywood, Heywood (Lanes.), were proposed for election as members. On the proposition of Dr. Rideal, seconded by Mr. A. C. Chapman, Mr. B. Kitto and Mr. C. H. Cribb were appointed auditors of the Society’s accounts for the past year. The following papers were read : ‘( The Occurrence of Barium Compounds in an Artesian Well Water,” by John “ A New Test for Formaldehyde,’j by Norman Leonard, B.Sc., and Harry M. “ On Caper Tea,” by Charles Estcourt ; and “The Adulteration of Sweet Spirit of Nitre with Potassium Nitrate,” by W. Messrs. Lester Reed, F.I.C., Harry Broadbent, F.I.C., W. T. Burgess, F.I.C., and White ; Smith ; F. Lowe, A.R.S.M. T. S. Goodwin were elected members of the Society.

ISSN:0003-2654    

DOI:10.1039/AN8992400029

出版商:RSC    

年代:1899

数据来源: RSC

摘要:

30 THE ANALYST. ON CAPER TEA. BY CHARLES ESTCOURT, F.I.C. (Read at the Meeting, Jawuary 4, 1899.) IN the early days of the Food Adulteration Act it was found that tea of all kinds was largely adulterated. Caper tea especially was found to show evidence of gross fraud on the part of the Chinese growers, and as this kind of tea was much used in the North, and especially in Lancashire, I then examined a large number of samples, the analyses of which demonstrated that this tea, as then sold, contained quartz and magnetic iron or0 nodules in quantities varying from 1 per cent. up to as much as 35 per cent. Other analysts also turned their attention to caper tea, the result being that gross adulteration was practically stamped out, as shown by the very few cases of caper tea certified by public analysts as adulterated since 1875.Out of a large number of samples of caper tea analysed in my laboratory from 1876 to 1897, only one contained more than 1 per cent. of mineral impurity. Mr. G. W. Wigner, in 1875, analysed a, number of samples of caper tea drawn from bond. The lowest total ash that he found was 5.75 per cent., and the highest 7-02 per cent. The ash insoluble in hydrochloric acid varied from 0.70 per cent. to 1.67 per cent. In seven out of the nine cases which he records the ash insoluble in hydrochloric acid was less than 1 per cent. Dr. Bell, in 1881, in two samples of caper tea from bond, found that the total ash (calculated on the dry tea) was 6.38 and 6.63 per cent., and the ash insoluble in hydrochloric acid 0.68 and 0-93 per cent.In 1882 Mr. Carter Bell pub- lished in the ANALYST the results of analyses of seventeen samples of caper tea pur- chased in Salford. The total ash of nine of these was less than 7 per cent., in only three cases exceeded 7.5 per pent., and in only one case exceeded 8 per cent. Dr. Bell, the late Principal of the Inland Revenue Laboratory, in his book on ‘‘ The Chemistry of Foods,” says, in reviewing his analyses of genuine imported teas,THE -ANALYST. $i .. the percentage of ash in no case, except one, . . . reaches 8 per cent. ..... on the dried tea. This last ash, when calculated on the original undried sample, is equivalent to 7.7 per cent. With‘ regard to mineral adulterants, Dr. BeU says, speaking of tea? generally: (‘ If the insoluble ash exceeds much more than 1 per cent., there is evidence of the addition of either sand, quartz, or other earthy impurities.” On August 24, 1898, I certified a caper tea as containing “ 2.25 per cent, “of sand and ferruginous earth.” At the hearing of the summons, the magistrates, without my analysis being questioned, sent the third portion of the sample to Somerset House.The following certificate (which, it will be observed, is not signed by either the Principal or Deputy Principal), was in due course received : ‘‘ GOVERNMENT LABORATORY, L 6 Clement’s Inn Passage, “ Strand, London, W.C. The sample of caper tea marked 532, and referred to in your letter of the We hereby 7th instant, was received here on the following day securely sealed. certify that we have analysed the tea with the following results : Total mineral matter ...... ... ... 7-50 per cent. Mineral matter soluble in water ... ... ... 2.36 ,, ,, in acid ... ... 3-12 ,, Silica (less sand) ... ... ... ... ... 1.38 ,, Sand ... ... ... ... ... ... 0.64 ,, ... 9 , ( 4 With thsview of ascertaining how far the sample in question differs from caper tea now met with in commerce, and of fair commercial quality, we have procured a number of authentic samples of such teas out of bond. On analysis they furnish the following results : Total mineral matter ... 6-74 7.90 7.26 7.20 6.44 7.08 8.00 Soluble in water ... 2.58 2.38 2.30 2-54 2-14 2.46 2.30 Soluble in acid .. ... 2-98 2.84 2.90 2.88 3.08 2.14 4-06 Silica (less sand) ... 1-04 0.32 1.76 1.40 1.06 1-26 1-08 Sand ... ...... 0.14 2-36 0.30 0.38 0.16 1-22 0-56 “ It is evident that the amount of foreign mineral matter in the case of the sample referred to us is not higher than that which may be present in genuine caper teas. We are of opinion, therefore, that the small proportion of extraneous matter present has become uuavoidably mixed in the process of collection and preparation. Per Cent. A. B. C. D. E, F. G. 6‘ As witness our hands this twenty-first day of September, 1898. (( (Signed) “G. LEWIN. “ H. W. DAVIES. ‘‘ THE CLERK TO THE MAGISTI:ATES, ( 6 City Police Court, Manchester.” The summons was dismissed. It will be seen that in the certificate the whole question of what genuine caper tea is, is begged. Samples of tea are taken out of bond and are assumed to be authentic, or (as in the term used lower down in the Somerset House certificate) genuine.33 THE ANALYST.These teas, as compared with those imported in 1875, appear to me to begelruine only inasmuch as they have not been stopped by the Customs, but have been, im- properly, allowed to go into consumption. The proportion of mineral matter insoluble in hydrochloric acid-not stated as a separate item in the official analyses, but calou- lated by deducting the water-soluble and acid-soluble ash from the total-would be as follows : Mineral matter insoluble in A. B. C. D. E. F. G. hydrochloric acid ... 1.18 2.68 2.06 1-78 1-22 2.48 1-64 Deduced in the same way, the ash insoluble in hydrochloric acid found at the Government Laboratory in the third portion of my sample was 2.02 per cent.I t will be seen that in these teas, taken from bond, in three cases the ash insoluble in hydro- chloric acid exceeded 2 per cent., being in one case 2-68 per cent., and in another 2-48 per cent.; whereas Dr. Bell, the former Principal of the Inland Revenue Laboratory, laid down the dictum that if the insoluble ash much exceeded 1 per cent,, there was evidence of the addition of either sand, quartz, or other earthy im- purities. In my sample I found nodules of quartz rolled up in the leaves, and there- fore cannot consider that the quartz had been, as is suggested in the certificate from the I t appears desirable that public analysts should be aware of the fact that the limit of earthy impurity fixed by Dr. Bell is no longer adopted at the Inland Revenue Laboratory, and that, apparently, any sample of caper tea containing not more than 2.68 per cent.of ash insoluble in hydrochloric acid is to be regarded as genuine. Attention may also be directed to the proportion of ash soluble in water in caper tea. Mr. Wiper, in 1875, found the proportion of ash soluble in water to vary from 2.64 to 3.66 per cent. in caper tea, the average of nine samples showing 3.07 per cent. In Dr. Beus two m p l e s , anslysed in 1881, the proportion of ash soluble in water, on the dry tea, were S.21 and 3-47 per cent., eqaivdent to 2-98 and 3-23 per oent. in the moist tea. Sinee the sample which gave rise to this paper contained, according to the analysis made in the Government Laboratory, only 2.36 per cent. of mineral matter soluble in water, it might, on the basis of the foregoing figures, be reltsonably regarded as containing exhausted leaves. But the figures found for soluble aeh in the seven samples quoted in the report from the Government Laboratory as authentic samples of mper tea out of bond range from 2.58 down to 2.14 per cent. ; and if these figures are to be accepted as fixing a standard of genuineness in the matter of the admixture of exhausted leaves, the limit of 3 per cent. virtually adopted by Dr. Bell presumably also disappears. overnment Laboratory, unavoidably mixed with the tea.

ISSN:0003-2654    

DOI:10.1039/AN8992400030

出版商:RSC    

年代:1899

数据来源: RSC