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 Cornell University Library 
 RA1211.W92 
 
 Micro-chemistry of poisons, including th 
 
 3 1924 017 521 836 
 
Cornell University 
 Library 
 
 The original of tiiis book is in 
 tine Cornell University Library. 
 
 There are no known copyright restrictions in 
 the United States on the use of the text. 
 
 http://www.archive.org/details/cu31924017521836 
 
MICRO-CHEMISTRY OF POISONS, 
 
 TNCLUDING THEIR 
 
 PHYSIOLOGICAL, PATHOLOGICAL, AND LEGAL RELATIONS: 
 
 ADAPTED TO 
 
 THE USE OF THE MEDICAL JURIST, PHYSICIAN, 
 AND GENERAL CHEMIST. 
 
 THEO. G. WORMLEY, M. D., 
 
 PROFESSOR OF CHEMISTRY AND TOXICOLOGY IN STARLING MEDICAL COLLEGE, AND OF NATURAL 
 SCIENCKS IN CAPITAL UNIVEUSITY, COLUMBUS, OHIO. 
 
 WITH SEVENTY-EIGHT ILLUSTRA TIONS UPON STEEL. 
 
 'AttA TTEipjjg- irdvra 6,v&p6'KOLCi f^ikkei. yivEa-&at. — Heeodotus. 
 
 <, ('^o 
 
 ^_ ('.. <y 
 
 "'V 
 
 NEW YORK: 
 
 WILLIAM WOOD & CO., 6i WALKER-STREET. 
 
 1869. 
 
Entered, according to Act of Congress, in the year 1867, 
 
 BY THEO. G. WORMLEY, M. D., 
 
 In the Clerli's Office of the District Court of the United States for the 
 Southern District of Ohio. 
 
 A' 
 
 printed at the 
 
 Western Methodist Book Concern, 
 
 cincinnati. 
 
WHO, 
 
 BY HER SKILLFUL HAND, 
 
 ASSISTED SO LARGELY IN ITS PREPARATION, 
 
 This Volume 
 
 AFFBCTIONATELr INSCRIBED. 
 
PREFACE. 
 
 Among the more prominent objects of the present volume 
 are to indicate the limit of the reactions of the different 
 tests that have heretofore been proposed, as also of those 
 novsr added, for the detection of the principal poisons, and 
 to point out the fallacies attending the reaction of each ; and, 
 also, to apply the microscope, vs^henever practicable, in de- 
 termining the nature of the different precipitates, sublimates, 
 etc., and to illustrate these, whenever of any practical utility, 
 by draw^ings. 
 
 Hitherto there have been but comparatively few attempts 
 to show the limit of the reaqtion of the different tests for 
 poisons, and in these the results have been so discrepant as 
 only to lead to confusion. This discrepancy has arisen chiefly 
 from the fact that the experimentalists have generally failed 
 to .state the exact conditions under which the tests were 
 applied. Without such statement, it is obvious that these 
 experiments can have little or no practical value. Thus, for 
 example, if in one instance only one grain of a hundredth 
 solution of the poison be examined, whilst in another one 
 hundred grains of a similar solution be employed, it is obvi- 
 ous that — although the degree of dilution is the same in 
 both — the absolute quantity of the poison present in the lat- 
 ter is one hundred times greater than in the former mixture. 
 
VI PREFACE. 
 
 and if either will yield a precipitate with a given reagent the 
 quantity produced from the latter will be one hundred times 
 greater than from the former. Similar results would be ob- 
 served in different quantities of all other solutions, until the 
 degree of dilution exceeded the solubility of the precipita- 
 ble substance produced by the reaction, when no quantity, 
 however great, of the solution would yield any precipitate 
 whatever. 
 
 As illustrative of the discrepancy that has obtained among 
 observers, in regard to the limit of some of the tests that 
 have been examined, may be cited the statements in regard 
 to Reinsch's test for arsenic, the limit of which is placed by 
 one observer at a dilution of 80,000, whilst another fixes it 
 at a dilution of 1,200,000, and others still, place it between 
 these extremes. Admitting that the amount of copper, in 
 regard to surface, employed by these experimentalists, was 
 the same, the results can only be reconciled on the supposi- 
 tion that the quantity of arsenical solution operated upon in 
 the second-named instance was about fourteen times greater 
 than in the first-mentioned ; when, although under very dif- 
 ferent degrees of dilution, the absolute quantity of arsenic 
 present was about the same in both instances. 
 
 Moreover, to give any practical value to investigations of 
 this kind, the experimenter should employ the least quantity 
 of the solution compatible with the application of the test. 
 In most instances, especially with the aid of the microscope, 
 one grain of a given solution of the poison will yield as sat- 
 isfactory results as a much larger quantity, the only differ- 
 ence being in the amount of precipitate produced. And in 
 all cases, unless the solution be exceedingly concentrated, a 
 given quantity of substan.ce in solution in one grain of fluid 
 will yield very much better results than the same quantity in 
 
PREFACE. VII 
 
 a larger amount of liquid, even when in the latter instance 
 the degree of dilution does not exceed the solubility of the 
 precipitable compound produced by the reaction. Through- 
 out the present treatise, the reactions of the liquid tests, with 
 very few exceptions, have been referred to one grain of the 
 poisonous solution. If the operator has sufficient material 
 on hand to permit the examination of larger quantities, his 
 results will, as a general rule, be correspondingly greater than 
 those stated in the text. 
 
 Heretofore the microscope has received but little attention 
 as an aid to chemical investigations, 'yet it is destined to very 
 greatly extend our knowledge in this department of study. 
 . As an evidence of the value of micro-chemical analysis, as 
 the Germans first styled it, it is only necessary to state that 
 it enables us by a very few minutes labor to recognise with 
 unerring certainty the reaction of the 100,000th part of a 
 grain of either hydrocyanic acid, mercury, or of arsenic. 
 Many instances might also be cited in which it, with equal 
 facility, enables us to detect the presence of very minute 
 quantities of substances, the true nature of which heretofore 
 could only be determined when present in comparatively 
 large quantity, and by considerable labor. 
 
 The microscopic illustrations, all of which are original, 
 were drawn from nature and transferred to steel, by her to 
 whom the work is inscribed. Each was prepared only after 
 an extended examination of the original under the conditions 
 usually present in ordinary analysis : if under these circum- 
 stances, the general form of the object illustrated diftei'ed from 
 that produced from the substance in its pure state, the differ- 
 ence is noted. In regard to the mechanical execution of the 
 illustrations, we leave it for others to pronounce, simply 
 
viii PREFACE. 
 
 remarking that the details of many of the figures can only 
 he obtained by means of a lens. 
 
 In this connection, the author of the illustrations desires 
 us to acknowledge her obligations and express her thanks to 
 Mr. F. E. Jones, of Cincinnati, through whose kind encour- 
 agement she was induced to undertake the execution of the 
 drawings upon steel, for his many valuable suggestions and 
 the interest he manifested in the work during its entire 
 preparation. She would also return her thanks to Mr. J. 
 E. Gavit, of JSTew York, for his kind interest in the under- 
 taking and progress of the work. 
 
 In addition to the points now mentioned, those acquainted 
 with the subject will find that in the consideration of nearly 
 every poison, more or less has been added to our knowledge, 
 either in regard to the methods of analysis, the introduction 
 of more delicate or confirmatory tests, or the methods of 
 separation from organic mixtures ; especially in regard to the 
 vegetable poisons, many of which can now be recovered from 
 the blood and other organic mixtures with as much certainty 
 as most of the mineral substances. It is rarely that any 
 allusion is made to these contributions, the only object of the 
 author having been to ascertain, according to his experiments, 
 the true value of the statements of others, and add to the 
 common stock of knowledge. In no instance, unless so stated, 
 was the reaction of a substance deduced from a single experi- 
 ment, but only from repeated experiments and, when practi- 
 cable, from different samples of material. If in any instance 
 the author has been misled, no one, for the cause of science, 
 will rejoice more than he in the demonstration of the error. 
 
 It was originally intended to confine the work exclusively 
 to the cheynistry of poisons, but in order to adapt it to a 
 
PREFACE. IX 
 
 larger class of readers, it was finally determined to also con- 
 sider their physiological and pathological effects, and point 
 out the treatment proper for each. In the preparation of 
 this part of the work, the principal existing treatises upon 
 the subject, together with many of the medical journals of 
 the day, were freely consulted; but to no systematic works 
 is the author more largely indebted than to the very valu- 
 able treatises On Poisons by Drs. Christison and Taylor 
 respectively, especially in the consideration of most of the 
 inorganic poisons. It has been the author's intention, so far 
 as practicable, to give due credit for all cases and matter 
 derived from others. "When the original article was not at 
 hand, reference is always made to the work consulted, this 
 rule being rigidly observed throughout the volume. 
 
 As within the last few years some two or three different 
 works have appeared .illustrating more or less the microscopic 
 appearances of poisons, the author may be permitted to state 
 that the present volume was projected as early as 1857, and 
 a prospectus announcing its plan published in March, 1861, 
 at which time the drawings were about completed. 
 
 The work is now presented to the public with the hope 
 that it will not only prove useful to those specially engaged 
 in the chemical investigation of poisons, but also to the 
 Medical Jurist, the Physician, and the General Chemist. 
 
 ConjMEUs, Ohio, Apkil, 1867. 
 
TABLE OF CONTEITS. 
 
 INTRODUCTION. 
 
 Micro-Chemistry of Poisons, Definition, . 
 Application of the Microscope, 
 Import of the term Poison, 
 Causes modifying the action of Poisons, 
 
 1. Idiosyncrasy, 
 
 2. Habit, .... 
 
 3. Disease, . . . , 
 Classification of Poisons, 
 Sources of Evidence of Poisoning, 
 
 I. Evidence from the Symptoms, 
 
 1. The Symptoms occur suddenly, . 
 
 2. They rapidly run their course. 
 Diseases resembling Poisoning, 
 Duties of Medical Attendant, 
 
 n. Evidence from Post-mortem Appearances, 
 
 Appearances rarely characteristic, 
 
 Irritant Poisons, usual effects of, 
 
 Narcotic Poisons, 
 
 Narcotico-Irritants, ..... 
 
 Appearances common to Poisoning and Disease, 
 
 Kedness of the Stomach, .... 
 
 Softening of the Stomach, .... 
 
 Ulceration and Perforation, .... 
 Points to be observed in Post-mortem Examinations, 
 in. Evidences from Chemical Analysis, 
 
 Importance of Chemical Evidence, 
 
 Substances requiring Analysis, 
 
 Precautions in regard to Analyses, 
 
 Failure to detect Fatal Quantity, 
 
 Value of individual Chemical Tests, 
 
 Failure to detect Poison, . 
 
 Of Chemical Reagents, 
 
 Of Chemical Apparatus, .... 
 Qualifications of the Analyst, 
 
 34 
 34 
 
 35 
 35 
 36 
 37 
 37 
 39 
 39 
 39 
 42 
 43 
 43 
 44 
 44 
 45 
 45 
 45 
 46 
 46 
 46 
 47 
 47 
 48 
 48 
 49 
 50 
 52 
 52 
 56 
 59 
 CO 
 60 
 
TABLE OF CONTENTS. 
 PART FIKST. 
 
 II^OEGAE"IO POISONS. 
 
 CHAPTER I. 
 
 THE ALKALIES: POTASH, SODA, AMMONIA. 
 
 PAOE. 
 
 General Chemical Nature, 65 
 
 Physiological Effecta, 65 
 
 Symptoms: 66 
 
 66 
 
 66 
 
 67 
 
 68 
 
 69 
 
 1. Of the Fixed Alkalies, 
 
 2. Of Ammonia 
 
 Period when Fatal, 
 Fatal Quantity, 
 
 Treatment, 
 
 Post-mortem Appearances, 
 Nitrate of Potash and other Alkaline Salts, 
 Chemical Properties of the Alkalies, 
 Distinguished from each other. 
 
 70 
 71 
 71 
 
 Section I. — Potash. 
 
 General Chemical Nature, 72 
 
 Density of Solutions of Potash, 73 
 
 Special Chemical Properties, . 73 
 
 1. Bichloride of Platinum Test, 74 
 
 2. Tartaric Acid, and Tartrate of Soda, 76 
 
 3. Carbazotic Acid, 79 
 
 Other Reagents, 80 
 
 Spectrum Analysis, 80 
 
 Separation from Organic Mixtures, 81 
 
 Quantitative Analysis, 82 
 
 Section II. — Soda. 
 
 General Chemical Nature, 
 
 Density of Solutions of Soda, .... 
 Special Chemical Properties, 
 
 Coloration of Flame, 
 
 1. Antimoniate of Potash Test, 
 
 2. Polarised Light, .... 
 Behavior with Carbazotic Acid, . 
 
 " " Tartaric " 
 
 » " Bichloride of Platinum, 
 
 Separation from Organic Mixtures, . 
 
 84 
 84 
 84 
 85 
 87 
 87 
 87 
 88 
 
TABLE OF CONTENTS. xm 
 
 Section III. — Ammonia. 
 
 PAGE. 
 
 General Chemical Nature, 88 
 
 Density of Solutions of Ammonia, ........ 88 
 
 Special Chemical Properties, 89 
 
 1. Bichloride of Platinuni Test, 89 
 
 2. Tartaric Acid, and Tartrate of Soda, 90 
 
 3. Carbazotic Acid, 91 
 
 4. Nessler's Test, 92 
 
 Sonnenschein's Test, 94 
 
 Antimoniate of Potash, 94 
 
 Separation from Organic Mixtures, 95 
 
 Quantitative Analysis, 96 
 
 CHAPTER II. 
 
 THE MINERAL ACIDS : SULPHURIC, NITRIC, HYDROCHLORIC. 
 
 General Nature and Effects, . . 97 
 
 Section I. — Sulphuric Acid. 
 
 History, 98 
 
 Symptoms, 98 
 
 Period when Fatal, 99 
 
 Fatal Quantity, 101 
 
 Treatment, 101 
 
 Post-mortem Appearances, 102 
 
 General Chemical Nature, 104 
 
 Density of Solution of Sulphuric Acid, 105 
 
 Special Chemical Properties, 106 
 
 1. Chloride of Barium Test, . . . . ' . . . 107 
 
 2. Nitrate of Strontia, Ill 
 
 3. Acetate of Lead, 112 
 
 4. Veratrine, 112 
 
 Other Reactions, 113 
 
 Separation from Organic Mixtures, 113 
 
 Suspected Solutions, 113 
 
 Contents of the Stomach, 117 
 
 From Organic Fahrics, 119 
 
 Quantitative Analysis, 119 
 
 Section II. — Nitric Acid. 
 
 Symptoms 120 
 
 Period when Fatal, 122 
 
 Fatal Quantity, 122 
 
 Treatment, 122 
 
XIV TABLE OF CONTENTS. 
 
 PAGE. 
 
 PosUmortem Appearances, 122 
 
 General Chemical Nature, 124 
 
 Density of Solutions of Nitric Acid, 125 
 
 Special Chemical Properties, 125 
 
 1. Copper Test, . 126 
 
 2. Gold Test, 127 
 
 3. Iron Test, 128 
 
 4. Indigo Test, 129 
 
 5. Brucine Test, 131 
 
 6. Narcotine, and Iodine Tests, 132 
 
 SchsfFer's, and Horsley's Tests, 133 
 
 Separation from Organic Mixtures, 134 
 
 Suspected Solutions, 134 
 
 Contents of the Stomach, ........ 136 
 
 From Organic Fabrics 137 
 
 Quantitative Analysis, 137 
 
 Section III. — Hydrochloric Acid. 
 
 Symptoms, 139 
 
 Period when Fatal, 139 
 
 Fatal Quantity, 140 
 
 Treatment, 141 
 
 Post-mortem Appearances, . 141 
 
 General Chemical Nature, 141 
 
 Density of Solutions of Hydrochloric Acid, 142 
 
 Special Chemical Properties, 143 
 
 1. Nitrate of Silver Test, 144 
 
 2. Nitrate of Suboxide of Mercury, 145 
 
 8. Acetate of Lead, 146 
 
 Separation from Organic Mixtures, 146 
 
 Suspected Solutions, 146 
 
 Contents of the Stomach, 148 
 
 From Organic Fabrics, 148 
 
 Quantitative Analysis, 149 
 
 CHAPTER III. 
 
 OXALIC AND HYDROCYAJSriC ACIDS, AND PHOSPHORUS. 
 
 Section I. — Oxalic Acid. 
 
 History, 150 
 
 Symptoms, 150 
 
 Period when Fatal, 152 
 
 Fatal Quantity, 152 
 
 Treatment, 153 
 
 Post-mortem Appearances, 154 
 
 General Chemical Nature, 155 
 
TABLE OF CONTENTS. 
 
 XV 
 
 Special Chemical Properties, . 
 
 1. Nitrate of Silver Test, 
 
 2. Sulphate of lime, 
 
 3. Chloride of Barium, . 
 
 4. Nitrate of Strontia, 
 
 5. Acetate of Lead, 
 
 6. Sulphate of Copper, 
 Separation from Organic Mixtures, 
 
 Suspected Solutions, . 
 Contents of the Stomach, 
 The Urine, 
 Quantitative Analysis, 
 
 PAGE. 
 
 156 
 156 
 158 
 159 
 160 
 161 
 162 
 163 
 163 
 164 
 166 
 167 
 
 Section II. — Hydrocyanic Acid. 
 
 History, 
 
 Symptoms, ...... 
 
 Period when Fatal, 
 
 Fatal Quantity, 
 
 Treatment, 
 
 Post-mortem Appearances, . 
 Chemical Properties, . . . , 
 General Chemical Nature, 
 Special Chemical Properties, . 
 
 1. Nitrate of Silver Test, 
 
 2. Iron Test, . . . , 
 
 3. Sulphur Test, . 
 Relative Delicacy of these Tests, 
 Other Reactions, 
 
 Separation from Organic Mixtures, 
 
 Examination for the Vapor, . 
 Method by Simple Distillation, 
 Distillation with an Acid, 
 From the Blood and Tissues, 
 Failure to detect the Poison, . 
 
 Quantitative Analysis, 
 
 167 
 169 
 171 
 172 
 173 
 174 
 175 
 175 
 176 
 177 
 180 
 183 
 185 
 186 
 187 
 187 
 188 
 189 
 190 
 191 
 192 
 
 Section III. — Phosphorus. 
 
 History, 192 
 
 Symptoms, 192 
 
 Period when Fatal, 193 
 
 Fatal Quantity, I94 
 
 Treatment, I95 
 
 Post-mortem Appearances, jgg 
 
 Chemical Properties, I97 
 
 General Chemical Nature, I97 
 
 Solubility, I97 
 
^vi TABLE OF CONTENTS. 
 
 . PAGE. 
 
 Special Chemical Properties, 198 
 
 1. MitscherUch's Method for Detection, 200 
 
 2. Hydrogen Method, 203 
 
 3. Ijipowitz " 205 
 
 Phosphoric Acid, 206 
 
 General Chemical Nature, 206 
 
 preparation, 206 
 
 Special Chemical Properties, 206 
 
 1. Nitrate of Silver Test, 206 
 
 2. Sulphate of Magnesia, ... .... 207 
 
 3. Molybdate of Ammonia, 208 
 
 Other Reactions, 210 
 
 Separation of Phosphorus from Organic Mixtures, 210 
 
 MitscherUch's Method, 211 
 
 Lipowitz Method, 212 
 
 Hydrogen " 213 
 
 Kecovery as Oxide of Phosphorus, 213 
 
 Failure to detect the Poison, 214 
 
 Quantitative Analysis, ..... ..... 214 
 
 CHAPTER IV. 
 
 ANTIMONY. 
 
 History, .... . . 
 
 Tartar Emetic, ... . . 
 
 Composition, 
 Symptoms, .... 
 
 Period when Fatal, 
 
 Fatal Quantity, 
 Treatment, ...... 
 
 Post-mortem Appearances, . 
 General Chemical Nature, 
 
 Solubility, 
 Special Chemical Properties, . 
 
 1. Sulphuretted Hydrogen Test, 
 
 2. Acetate of Lead, . 
 
 3. Zinc Test, . 
 
 4. Copper Test, .... 
 
 5. Antimonuretted Hydrogen, 
 Fallacies, 
 
 Action of the Mineral Acids, . 
 " " Caustic Alkalies, 
 
 Other Reactions, 
 Separation from Organic Mixtures, 
 Suspected Solutions, 
 From the Tissues, 
 Quantitative Analysis, 
 
 216 
 216 
 216 
 216 
 218 
 219 
 220 
 220 
 221 
 221 
 222 
 222 
 224 
 225 
 225 
 227 
 230 
 231 
 232 
 232 
 233 
 233 
 236 
 237 
 
TABLE OF CONTENTS. xvii 
 
 CHAPTER V. 
 
 ARSENIC. 
 I. Metallic Arsenic. 
 
 PAGE. 
 
 History and Chemical Nature, 238 
 
 Physiological Effects, . 239 
 
 Special Chemical Properties, 239 
 
 Compounds of Arsenic, ... 240 
 
 II. Arsenious Acid. 
 
 History and Varieties, .... 240 
 
 Symptoms, 241 
 
 Period when Fatal, 244 
 
 Fatal Quantity, 244 
 
 Treatment, 245 
 
 Post-mortem Appearances, 248 
 
 Antiseptic Properties, 248 
 
 General Chemical Nature, 250 
 
 Solubility, 250 
 
 Special Chemical Properties, 253 
 
 Of Solid Arsenious Acid, 253 
 
 Vaporisation, 253 
 
 Sublimation, ........... 254 
 
 Reduction, 255 
 
 Of Solutions of Arsenious Acid, 258 
 
 1. Ammonio-Nitrate of Silver Test, 259 
 
 2. Ammonio-Sulphale of Copper, 261 
 
 3. Sulphuretted Hydrogen, 263 
 
 4. Keinsch's Test, 269 
 
 5. Marsh's Test, . 278 
 
 Bloxam's Method, 292 
 
 Other Reactions, 294 
 
 1. Lime-water, 294 
 
 2. Iodide of Potassium, 295 
 
 3. Bichromate of Potash, 295 
 
 4. Potash and Sulphate of Copper, ....'. 295 
 Separation from Organic Mixtures, 296 
 
 Suspected Solutions, . 296 
 
 Vomited Matters, ... 297 
 
 Contents of the Stomach, . . 297 
 
 From the Tissues, 299 
 
 Fresenius and Babo's Method, 300 
 
 Method of Danger and Flandin, 305 
 
 " " Duflos and Hirsch, 306 
 
 By Distillation, 306 
 
 From the Urine, 307 
 
xvni TABLE OF CONTENTS. 
 
 PAGE. 
 
 Failure to Detect the Poison, 307 
 
 Detection after Long Periods, 308 
 
 Quantitative Analysis, . 309 
 
 III. Arsenic Acid. 
 
 General Chemical Nature, 310 
 
 Physiological Effects, 311 
 
 Special Chemical Properties, 311 
 
 1. Sulphuretted Hydrogen Test, 312 
 
 2. Ammonio-Sulphate of Copper, 314 
 
 3. Nitrat« of Silver, 315 
 
 4. Reinsch's Test .315 
 
 5. Ammonio-Sulphate of Magnesia, 316 
 
 Other Reactions, 317 
 
 Quantitative Analysis, 317 
 
 CHAPTER VI. 
 
 MERCURY. 
 
 General Properties, 319 
 
 Physiological Effects, - 319 
 
 Combinations, 319 
 
 Corrosive Sublimate, 320 
 
 Composition, .......... 320 
 
 Symptoms, ., 320 
 
 Period when Fatal, 323 
 
 Fatal Quantity, 324 
 
 Treatment, 324 
 
 Post-mortem Appearances, . , 325 
 
 General Chemical Nature, 327 
 
 ' Solubility, 327 
 
 Special Chemical Properties, 328 
 
 In the Solid State, 328 
 
 Of Solutions of Corrosive Sublimate, 331 
 
 1. Ammonia Test, 331 
 
 2. Potash and Soda, 332 
 
 3. Iodide of Potassium, 333 
 
 4. Sulphuretted Hydrogen, 334 
 
 5. Chloride of Tin, 336 
 
 6. Copper Test, 337 
 
 7. Nitrate of Silver, 343 
 
 Other Reagents, 344 
 
 Separation from Organic Mixtures, 344 
 
 Suspected Solutions, 345 
 
 Vomited Matters, 346 
 
 Contents of the Stomach, 346 
 
 From the Tissues, 348 
 
TABLE OF CONTENTS. xix 
 
 PAGE. 
 
 From the Urine, 351 
 
 Failure to Detect the Poison, 351 
 
 Quantitative Analysis, 352 
 
 CHAPTER VII. 
 
 LEAD, COPPER, ZINC. 
 
 Section I. — Lead. 
 
 History and Chemical Nature, 354 
 
 Physiological Effects 355 
 
 Acetate of Lead, 355 
 
 Symptoms, 355 
 
 Period when Fatal, 356 
 
 Fatal Quantity, 357 
 
 Treatment, 357 
 
 Post-mortem Appearances, 357 
 
 General Chemical Nature, . 358 
 
 Solubility, 358 
 
 Special Chemical Properties, 359 
 
 In the Solid State, 359 
 
 Of Solutions of Acetate of Lead, 360 
 
 1. Sulphuretted Hydrogen Test, 361 
 
 2. Sulphuric Acid, 363 
 
 3. Hydrochloric Acid, 364 
 
 4. Iodide of Potassium, 365 
 
 5. Chromate of Potash, 366 
 
 6. Potash and Ammonia, 367 
 
 7. The Alkaline Carbonates, 367 
 
 8. Oxalate of Ammonia, 368 
 
 9. Zinc Test, 368 
 
 Other Reagents, 369 
 
 Separation from Organic Mixtures, 369 
 
 Suspected Solutions, 369 
 
 Contents of the Stomach, 370 
 
 From the Tissues, 371 
 
 The Urine, 372 
 
 Quantitative Analysis, 372 
 
 Section II. — Copper. 
 
 History and Chemical Nature, 373 
 
 Combinations, 374 
 
 Sulphate of Copper and Verdigris, 374 
 
 Physiological Effects, 375 
 
 Symptoms, 375 
 
 Period when Fatal, 376 
 
 Fatal Quantity, 377 
 
XX TABLE OF CONTENTS. 
 
 PAQE. 
 
 Treatment, 377 
 
 PosUmortem Appearances, 37S 
 
 Chemical Properties, 378 
 
 In the Solid State, 378 
 
 Of Solutions of Salts of Copper, 379 
 
 1. Sulphuretted Hydrogen Test, 379 
 
 2. Ammonia, 381 
 
 3. Potash and Soda, 882 
 
 i. Ferrocyanide of Potassium, 383 
 
 5. Iron Test, . • 384 
 
 6. Platinum and Zinc Test, 385 
 
 7. Arsenite of Potash, 386 
 
 8. Chromate of Potash, 386 
 
 9. Ferricyanide of Potassium, 387 
 
 10. Iodide of Potassium, 387 
 
 Detection of the Acid, 388 
 
 Separation from Organic Mixtures, 388 
 
 Suspected Solutions, 388 
 
 Contents of the Stomach, 389 
 
 From the Tissues, 390 
 
 The Urine, ' 391 
 
 Quantitative Analysis, 391 
 
 Section III. — Zinc. 
 
 History and Chemical Nature, 392 
 
 Sulphate of Zinc, 393 
 
 Chloride of Zinc, . . 394 
 
 Symptoms, 394 
 
 Treatment, . " . 396 
 
 Post-mortem Appearances, 396 
 
 Chemical Properties of Salts of Zinc, 397 
 
 In the Solid State, 397 
 
 When in Solution, 398 
 
 1. Sulphuretted Hydrogen Test, 398 
 
 2. Potash and Ammonia, . 400 
 
 3. Ferrocyanide of Potassium, 400 
 
 4. Ferricyanide of Potassium, 401 
 
 5. Oxalic Acid, 402 
 
 6. Chromate of Potash, 402 
 
 7. Phosphate of Soda, 403 
 
 Detection of the Acid, 403 
 
 Separation from Organic Mixtures, ........ 404 
 
 Contents of the Stomach, 404 
 
 From the Tissues, 405 
 
 Quantitative Analysis, 405 
 
TABLE OF CONTENTS. 
 
 PART SECOND. 
 
 VEGETABLE POISOI^S. 
 
 INTRODUCTION. 
 
 PAGE. 
 
 General Nature of Vegetable Poisons, 409 
 
 Separation from Complex Organic Mixtures, 410 
 
 1. Method of Stas, 411 
 
 2. Rodgers and Girdwood's Method, 416 
 
 3. Method of Uslar and Erdmann, 417 
 
 4. Process of Graham and Hofmann, 419 
 
 5. Method by Dialysis, 420 
 
 CHAPTER I. 
 VOLATILE ALKALOIDS: NICOTINE, CONINE. 
 
 Section I. — Nicotine. (Tobacco.) 
 
 History, .... 423 
 
 Preparation, 423 
 
 Symptoms, 424 
 
 Period when Fatal, 426 
 
 Fatal Quantity, 427 
 
 Treatment, . ^ 427 
 
 Post>-mortem Appearances, 427 
 
 General Chemical Nature, 428 
 
 Solubility, 428 
 
 Special Chemical Properties, 429 
 
 1. Bichloride of Platinum Test, 430 
 
 2. Corrosive Sublimate, 432 
 
 3. Carbazotic Acid, 483 
 
 4. Iodine in Iodide of Potassium, 434 
 
 5. Terchloride of Gold, 435 
 
 6. Bromine in Bromohydric Acid, 436 
 
 7. Tannic Acid, 436 
 
 Other Reagents, 437 
 
 Separation from Organic Mixtures, 437 
 
 Suspected Solutions and Contents of the Stomach, . . . 438 
 
 From the Tissues, 440 
 
 From the Blood, 440 
 
 General Method of Distillation, 442 
 
TABLE OF CONTENTS. 
 
 Section III. — Conine. (Conium Maculatum.) 
 
 PAGE. 
 
 History, 443 
 
 Preparation, . . 444 
 
 Symptoms 444 
 
 Treatment, 446 
 
 Posfr-mortem Appearances, 446 
 
 General Chemical Nature, 447 
 
 Solubility, 448 
 
 Special Chemical Properties, 448 
 
 1. Terchloride of Gold Test, 450 
 
 2. Carbazotic Acid, 451 
 
 3. Corrosive Sublimate, 451 
 
 4. Iodine in Iodide of Potassium, 451 
 
 5. Bromine in Bromohydric Acid, 452 
 
 6. Nitrate of Silver, 453 
 
 7. Tannic Acid, 453 
 
 Other Reagents, 454 
 
 Fallacies, 454 
 
 Separation from Organic Mixtures, 455 
 
 CHAPTER II. 
 OPIUM AND SOME OF ITS CONSTITUENTS. 
 
 I. — Opium. 
 
 History and Chemical Nature, 457 
 
 Symptoms, 458 
 
 Period when Fatal, 460 
 
 Fatal Quantity, 461 
 
 Treatment, ... 463 
 
 Postr-mortem Appearances, . . 465 
 
 Physical and Chemical Properties, . 465 
 
 II. — Morphine . 
 
 History and Preparation, 466 
 
 Symptoms, 467 
 
 Period of Death and Fatal Quantity, 468 
 
 Treatment and Post-mortem Appearances, 470 
 
 General Chemical Nature, 470 
 
 Solubility, 471 
 
 Special Chemical Properties, 473 
 
 In the Solid State, 473 
 
 Of Solutions of Salts of Morphine, 473 
 
 1. Potash and Soda Teats, 473 
 
 2. Ammonia, 474 
 
TABLE OF CONTENTS. 
 
 XXIH 
 
 PAGE. 
 
 3. Nitric Acid, 475 
 
 4. Iodic Acid, 476 
 
 5. Sesquichloride of Iron, 477 
 
 6. Iodide of Potassium, 478 
 
 7. Cliromate of Potasli, 479 
 
 8. Terchloride of Gold, 479 
 
 9. Bichloride of Platinum 480 
 
 10. Iodine in Iodide of Potassium, 480 
 
 11. Bromine in Bromohydric Acid, 481 
 
 12. Carbazotio Acid, . . 481 
 
 13. Chlorine and Ammonia, 482 
 
 Other Reagents, 482 
 
 Relative Value of the Preceding Tests, 483 
 
 III. — Meconic Acid. 
 
 History, 483 
 
 Preparation, 483 
 
 Physiological Effects, 484 
 
 General Chemical Nature, ..... .... 484 
 
 Solubility, 484 
 
 Special Chemical Properties, .......... 485 
 
 1. Sesquichloride of Iron Test, 
 
 2. Acetate of Lead, . 
 
 3. Chloride of Barium, 
 
 4. Hydrochloric Acid, 
 5- Nitrate of Silver, 
 
 6. Ferricyanide of Potassium, 
 
 7. Chloride of Calcium, 
 Other Reagents, 
 
 486 
 488 
 489 
 490 
 490 
 491 
 491 
 492 
 
 SEPARATION OF MECONIC ACID AND MORPHINE FROM ORGANIC MIXTURES. 
 
 Suspected Solutions and Contents of the Stomach, 
 
 Meconic Acid, .... 
 
 Morphine, .... 
 
 Porphyroxine, .... 
 
 Examination for Morphine alone, 
 
 From the Tissues, 
 
 From the Blood, 
 
 The Urine, .... 
 Failure to Detect the Poison, 
 Quantitative Analysis of Morphine, 
 
 492 
 493 
 495 
 498 
 499 
 500 
 500 
 503 
 503 
 504 
 
 IV. — Narcotine. 
 
 History, . 
 Preparation, 
 Physiological Effects, 
 
 504 
 505 
 505 
 
XXIV 
 
 TABLE OF CONTENTS. 
 
 Chemical Properties, 
 
 1. Potash and Ammonia Tests, . 
 
 2. Sulphuric Acid and Nitrate of Potash, 
 
 3. Acetate of Potash, 
 
 4. Chromate of Potash, 
 
 5. Sulphocyanide of Potassium, 
 
 . 6. Chloride of Gold, .... 
 
 7. Iodine in Iodide of Potassium, 
 
 8. Bromine in Bromohydric Acid, 
 
 9. Ferrooyanide of Potassium, 
 
 10. Carhazotic Acid, .... 
 Other Reagents, .... 
 
 PAGE. 
 
 505 
 507 
 508 
 509 
 510 
 510 
 511 
 511 
 512 
 612 
 513 
 518 
 
 V. — Codeine. 
 
 History, 513 
 
 Preparation, 514 
 
 Physiological Effects, 514 
 
 Chemical Properties, 514 
 
 1. Potash and Ammonia Tests, ........ 516 
 
 2. Iodine in Iodide of Potassium, ....... 517 
 
 3. Bromine in Bromohydric Acid, ....... 517 
 
 4. Sulphocyanide of Potassium, 518 
 
 5. Bichromate of Potash, . . . . . . . . .518 
 
 6. Chloride of Gold, 518 
 
 7. Bichloride of Platinum, 519 
 
 8. Carhazotic Acid, . ' 519 
 
 9. Nitric Acid and Potash, 519 
 
 Other Reagents, 520 
 
 VI. — Narceine. 
 
 History and Preparation, 520 
 
 Physiological Effects, 521 
 
 Chemical Properties, 521 
 
 1. Iodine in Iodide of Potassium Test, 522 
 
 2. Bromine in Bromohydric Acid, 523 
 
 3. Chloride of Gold, 523 
 
 4. Bichloride of Platinum : . . 523 
 
 5. Carhazotic Acid, 524 
 
 6. Bichromate of Potash, 524 
 
 Other Reagents, 524 
 
 VII. — Opianyl. 
 
 History, 524 
 
 Preparation, 'i " • ^^^ 
 
 Physiological Effects, 525 
 
TABLE OF CONTENTS. xxv 
 
 PAGE. 
 
 Chemical Properties, 525 
 
 1. Iodine in Iodide of Potassium Test, 526 
 
 2. Bromine in Bromohydrio Acid, . . ... 526 
 
 3. Siilphuric Acid and Heat, 527 
 
 Other Reagents, 528 
 
 CHAPTER III. 
 
 NUX VOMICA, STRYCHNINE, BRUCINE. 
 
 I. Nux Vomica. 
 
 History and Composition, .... 529 
 
 Symptoms, 529 
 
 Period when Fatal, 531 
 
 Fatal Quantity, . 532 
 
 Treatment, 532 
 
 Post-mortem Appearances, . 532 
 
 Chemical Properties, 533 
 
 II. Strychnine. 
 
 History, 534 
 
 "Preparation, 535 
 
 Symptoms, 536 
 
 Period when Fatal, 541 
 
 Fatal Quantity, 542 
 
 Treatment, 543 
 
 Post-mortem Appearances, 546 
 
 General Chemical Nature, . . " 548 
 
 Solubility, 549 
 
 Special Chemical Properties, 550 
 
 In the Solid State, 550 
 
 Of Solutions of Strychnine, 551 
 
 1. Potash and Ammonia Tests, . 652 
 
 2. Color Test, 553 
 
 3. Sulphocyanide of Potassium, 566 
 
 4. Iodide of Potassium, . . 567 
 
 5. Bichromate of Potash, 567 
 
 6. Chloride of Gold 570 
 
 7. Bichloride of Platinum, 571 
 
 8. Carhazotic Acid, 572 
 
 9. Corrosive Sublimate, 572 
 
 10. Iodohydi;^rgyrate of Potassium, 573 
 
 11. Ferricyanide of Potassium, 574 
 
 12. Iodine in Iodide of Potassium, 575 
 
 13. Bromine in Bromohydric Acid, 576 
 
 14. Physiological Test, 576 
 
 Other Keagents, 578 
 
XXVI TABLE OF CONTENTS. 
 
 PAa£. 
 
 Separation from Organic Mixtures, 579 
 
 From Nux Vomica, 579 
 
 Suspected Solutions and Contents of the Stomacli, .... 579 
 
 Method by Dialysis, 582 
 
 From the Tissues, 586 
 
 The Blood, 587 
 
 From the Urine, 590 
 
 Failure to Detect the Poison, 591 
 
 Quantitative Analysis, 593 
 
 III. Brucine. 
 
 History and Preparation, 593 
 
 Physiological Effects, 594 
 
 General Chemical Nature, 594 
 
 Solubility, 595 
 
 Special Chemical Properties, 595 
 
 1. Potash and Ammonia Tests, ........ 596 
 
 2. Nitric Acid and Chloride of Tin Test, 597 
 
 3. Sulphuric Acid and Nitrate of Potash, 598 
 
 4. Sulphooyanide of Potassium, 599 
 
 5. Bichromate of Potash, ......... 600 
 
 6. Bichloride of Platinum, 600 
 
 7. Terchloride of Gold, . . 601 
 
 8. Carbazotic Acid, 602 
 
 9. Ferricyanide of Potassium, 602 
 
 10. Iodine in Iodide of Potassium, 608 
 
 11. Bromine in Bromohydrio Acid, 603 
 
 Other Eeactions, 604 
 
 Separation from Organic Mixtures, 604 
 
 CHAPTER IV. 
 
 ACONITINE, ATROPINE, DATURINE. 
 
 Section I. — Aconitine. (Aconite.) 
 
 History and Preparation, 606 
 
 Symptoms, 608 
 
 Period when Fatal, 610 
 
 Fatal Quantity, 610 
 
 Treatment, 612 
 
 Post-mortem Appearances, 613 
 
 Chemical Properties, ,, .' . . 614 
 
 Solubility, 616 
 
 Of Solutions of Aconitine, 616 
 
 1. Potash and Ammonia Tests, 616 
 
 2. Terchloride of Gold Test, 617 
 
 3. Carbazotic Acid, 617 
 
TABLE OF CONTENTS.' xxvii 
 
 PAGE. 
 
 i. Iodine in Iodide of Potassium, 617 
 
 5. Bromine in Bromohydric Acid, 618 
 
 Other Reagents, 618 
 
 Fallacies of Preceding Tests, . 618 
 
 Physiological Test, 619 
 
 Separation from Organic Mixtures, 619 
 
 Suspected Solutions and Contents of the Stomach, .... 619 
 
 From the Blood, 620 
 
 Section II. — Atropine. (Belladonna.) 
 
 History, 621 
 
 Preparation, 622 
 
 Symptoms, 623 
 
 Treatment, 628 
 
 Post-mortem Appearances, 628 
 
 Chemical Properties, 628 
 
 Solubility, 629 
 
 Of Solutions of Atropine, 629 
 
 1. Potash and Ammonia Tests, 630 
 
 2. Bromine in Bromohydric Acid Test, 630 
 
 8. Carhazotic Acid, 631 
 
 4. Terchloride of Gold, 632 
 
 5. Iodine in Iodide of Potassium, . . . . . . . 633 
 
 Other Reagents, 633 
 
 Physiological Test, 633 
 
 Separation from Organic Mixtures, 634 
 
 Suspected Solutions and Contents of the Stomach, .... 634 
 
 From the Blood, 636 
 
 Section III. — Daturine. (Stramonium.) 
 
 History and Preparation, 636 
 
 Symptoms, 637 
 
 Treatment, 640 
 
 Post-mortem Appearances, 640 
 
 Chemical Properties, 640 
 
 Separation from Organic Mixtures, 641 
 
 CHAPTER V. 
 VERATRINE, SOLANINE. 
 
 Section I. — Veratrine. (White Hellebore.) 
 
 History and Preparation, 643 
 
 Symptoms. — Veratrum Album, 645 
 
 Veratrum Viride, ......... 646 
 
 Veratrine, 647 
 
xxvm TABLE OF CONTENTS. 
 
 PAGE. 
 
 Treatment, 648 
 
 Post-mortem Appearances, 648 
 
 Chemical Properties, 648 
 
 Solubility, 650 
 
 Of Solutions of Veratrine, 651 
 
 1. Potash and Ammonia Tests, 651 
 
 2. Sulphuric Acid Test, 652 
 
 3. Chloride of Gold, 653 
 
 4. Bromine in Bromohydric Acid, 654 
 
 5. Iodine in Iodide of Potassium, 655 
 
 6. Carbazotio Acid, .......... 655 
 
 7. Bichromate of Potash, 655 
 
 Other Reagents, 656 
 
 Separation from Organic Mixtures, 656 
 
 Contents of the Stomach, 656 
 
 From the Blood, 657 
 
 Section II. — Solanine. (Nightshade.) 
 
 History, 657 
 
 Preparation, 657 
 
 Symptoms, 658 
 
 Treatment 660 
 
 Post-mortem Appearances, 660 
 
 Chemical Properties, ... 660 
 
 Solubility, 661 
 
 Of Solutions of Solanine, 662 
 
 1. Potash and Ammonia Tests, 663 
 
 2. Sulphuric Acid Test, 663 
 
 3. Iodine in Iodide of Potassium, 665 
 
 4. Chromate of Potash, 665 
 
 5. Bromine in Bromohydric Acid, 666 
 
 Other Reagents, 666 
 
 Separation from Organic Mixtures, . 667 
 
ILLUSTRATIONS UPON STEEL. 
 
 PLATE I. 
 
 FiQ. 1. -jj^ grain Potash, in the form of nitrate or chloride, -j- Bichloride of 
 Platinum, X 225 diameters. 
 
 2. -j-Jjy grain Potash, as nitrate, -\- Tartaric Add, x 100 diameters. 
 
 3. yj^ grain Potash, as chloride, + Tartrate of Soda, X 80 diameters. 
 
 4. j^ grain Potash, as nitrate, -|- Carbazotic Acid, X 40 diameters. 
 
 5. jj^ grain Ammonia, as chloride, + Cariazotic Add, X 40 diameters. 
 
 6. ^ grain Soda, + Carbazotic Add, X 40 diameters. 
 
 PLATE IL 
 
 Fig. 1. -^ — j^ grain Soda, + Antimoniate of Potash, y(, 100 diameters. 
 
 2. ^ grain Soda, -f- Tartaric Add, X 40 diameters. 
 
 3. iTrViy gi'S'iii Soda, as chloride, + Bichloride of Platinum, X 40 diameters. 
 
 4. -j^ grain Sulphukic Acid, -(- Chloride of Barium, X 100 diameters. 
 
 5. Htdbofiuosilicic Acid, + Chloride of Barium, X 100 diameters. 
 
 6. -j-J^ grain Sulphuric Acid, + Nitrate of Strontia, X 75 diameters. 
 
 PLATE III. 
 
 FiQ. 1. yj^ grain Htdkoohlorio Acid, -\- Acetate of Lead, X 40 diameters. 
 
 2. Ywm gi'^'in Oxalic Acid, on spontaneous eTaporation, X 80 diameters. 
 
 3. xTrVff gi'^ii Oxalic Acid, -f- Chloride of Caldum, X 225 diameters. 
 
 4. yJu grain Oxalic Acid, + Chloride of Barium, X 80 diameters. 
 
 5. .j-i^ grain Oxalic Acid, + Nitrate of Strontia, X 125 diameters. 
 
 6. g jj j grain Oxalic Acid, + Acetate of Lead, X 80 diameters. 
 
 PLATE IV. 
 
 Y^-!n! grain HYDEOorANic Acid vapor, + Nitrate of Silver, X 222 diameters. 
 
 ^^^^^^ grain Hydrocyanic Acid vapor, -)- Nitrate of Silver, X 125 diameters. 
 
 Tinnr gi'^in Phosphoric ^ Acid, -j- -^''^''"""''-Su^Aaie o/ Magnesia, X 80 
 
 diameters. 
 Tartar Emetic, from hot supersaturated solution, X 40 diameters. 
 Arsenious Acid, sublimed, X 125 diameters. 
 
 t4^ grain Arseniocs Acid + Ammonio-Nitrate of Silver, X 75 diameters. 
 
 29 
 
 FlQ. 
 
 1. 
 
 (c 
 
 2. 
 
 li 
 
 3. 
 
 a 
 
 4. 
 
 u 
 
 5. 
 
ILLUSTRATIONS UPON STEEL. 
 
 PLATE V. 
 
 Pig. 1. j^ grain Aksenic Acid, -|- Ammonio-Sulphate of Magnesia, X 75 di- 
 ameters. 
 
 2. Corrosive Sublimate, sublimed, X 40 diameters. 
 
 3. ^j- grain Lead, + diluted Sulphuric Add, X 80 diameters. 
 
 4. -j-J^ grain Lead, + diluted Hydrochloric Acid, X 80 diameters. 
 
 5. ^Jj^ grain Lead, -\- Iodide of Potassium, X 80 diameters. 
 
 6. ytVu gi"*in Zinc, + Oxalic Acid, X 80 diameters. 
 
 PLATE VL 
 
 Fig. 1. j-J^ grain Nicotine, + Bichloride of Platinum, X 40 diameters 
 
 2. -j^j- grain Nicotine, -f- Corrosive Sublimate, X 40 diameters. 
 
 3. Tirtrff grain Nicotine, -j- Carlazoiic Acid, X 40 diameters. 
 
 4. Conine, pure, -|- vapor of Hydrochloric Add, X 40 diameters. 
 
 5. -j-J^ grain Conine, -|- Carlazotic Add, X 40 diameters. 
 
 6. ^^ grain Morphine, -|- Potash or Ammonia, X 40 diameters. 
 
 PLATE VII. 
 
 FiQ. 1. Ywu grain Morphine, -\- Iodide of Potassium, X 40 diameters. 
 
 2. jj^ grain Morphine, + Chrmnate of Potash, X 80 diameters. 
 
 3. Yh'S gr^iin Morphine, -|- Bichloride of Platinum, X 80 diameters. 
 
 4. -j^^ grain Meconic Acid, -\- Chloride of Barium, X 80 diameters. 
 
 5. j^ grain Meconic Acid, -\- Hydrochloric Add, X 75 diameters. 
 
 6. ^^ grain Meconic Acid, -|- Ferricyanide of Potassium, X 40 diameters. 
 
 PLATE VIII. 
 
 Fig. 1. -j-rff gi'^'i" Meconic Acid, + Chloride of Caldum, X 75 diameters. 
 
 2. 1^5^ grain Narcotine, + Potash or Ammonia, X 40 diameters. 
 
 3. -fj^ grain Narcotine, -\- Acetate of Potash, X 80 diameters. 
 
 4. yJtt gi'ain Codeine, -|- Iodine in Iodide of Potassium, X 40 diameters. 
 
 5. Y^ grain Iodide op Codeine, from alcoholic solution, X 75 diameters. 
 
 6. j^ grain Codeine, + Sulphocyanide of Potassium, X 40 diameters. 
 
 PLATE IX. 
 
 FlG. 1. j^ grain Codeine, -j- Bichromate of Potash, X 40 diameters. 
 
 " 2. -j-ffTT grain Codeine, -f- Iodide of Potassium, x 40 diameters. 
 
 " ^- TTnrff grain Narceine, + Iodine in Iodide of Potassium, X 40 diameters. 
 
 " ^- rhr grain Narceine, -[- Bichromate of Potash, X 40 diameters. 
 
 " 5- T^ grain Opiantl, + Iodine in Iodide of Potassium, X 40 diametera 
 
 " 6- TOT grain Opianyi, + Bromine in Bromohydric Add, X 40 diameters. 
 
ILLUSTRATIONS UPON STEEL. 
 
 PLATE X. 
 
 Immonia. V 40 c 
 
 X 40 diameters. 
 
 Fio. 1. j^ grain Stktchnine, -|- Potash or Ammonia, X 40 diameters. 
 " ^- rhs gi'^iii Stkychnine, -j- Sulphocyanide of Potassium, X 40 diam( 
 " ^- Titr S^^^^ Stkychnine, + Bichromate of Potash, X 40 diameters. 
 
 " ^" Tsim grain Strychnine, -{- Bichromate of Potash, X 80 diameters. 
 
 " ^- ttW grain Strychnine, + Chloride of Gold, X 40 diameters. 
 
 " ^- Tjhsi! S^^^^ Strychnine, + Bichloride of Platinum, X 40 diameters 
 
 IG. 
 
 . 1. 
 
 Li 
 
 2. 
 
 U 
 
 3. 
 
 (( 
 
 4. 
 
 U 
 
 5. 
 
 u 
 
 6. 
 
 PLATE XI. 
 
 Ttnnr grain Strychnine, + Carbazotic Acid, X 80 diameters. 
 
 YjTy grain Strychnine, + Corrosive Sublimate, X 40 diameters. 
 
 lin gi'ain Strychnine, -|- Ferricyanide of Potassium, X 40 diameters. 
 TstTS grain Strychnine, -|- Iodine in Iodide of Potassium, X 80 diameters. 
 
 T^Tf grain Brucine, -|- Potash or Ammonia, X 40 diameters. 
 
 jj^ grain Brucine, + Sulphocyanide of Potassium, X 40 diameters. 
 
 PLATE XII. 
 
 Fig. 1. Y^^ grain Brucine, + Bichromate of Potash, X 80 diameters. 
 " ^- TiyW gi^ain Brucine, + Bichloride of Platinum, X 40 diameters. 
 " ^- tJtt gi^ain Brucine, -|- Ferrieyanide of Potassium, x 40 diameters. 
 " 4. -j^ grain Atropine, + Potash or Ammonia, X '75 diameters. 
 " ^- T^ grain Atropine, -\- Bromine in Bromohydric Add, X 75 diameters. 
 " ^' xaSao grain Atropine, -j- Bromine in Bromohydric Acid, X 125 diameters. 
 
 PLATE XIII. 
 
 Fig. 1. 1-J^ grain Atropine, -\- Carbazotic Acid, X 80 diameters. 
 
 " 2. YBTT gi'ain Atropine, + Chloride of Gold, X 80 diameters. 
 
 " ^- TTO grain Veratkinb, -|- Chloride of Gold, x 40 diameters. 
 
 " 4. T^-g grain Veratrine, -j- Bromine in Bromohydric Add, X 80 diameters. 
 
 " 5. SoiANiNE, from alcoholic solution, X 80 diameters. 
 
 " ^- TOT grain SoLANiNE, as sulphate, on spontaneous evaporation, x 80 
 diameters. 
 
MICRO-CHEMISTRY OF POISONS. 
 
 INTKODTJOTIOH'. 
 
 DEFINITION ; APPLICATION OF THE MICROSCOPE IMPORT OF THE 
 
 TERM POISON ; MODIFYING CIRCUMSTANCES — CLASSIFICATION 
 
 OF POISONS SOURCES OF EVIDENCE OF POISONING: 
 
 EVIDENCE FROM SYMPTOMS— FROM POST-MORTEM 
 APPEARANCES FROM CHEMICAL ANALYSIS. 
 
 By the term Miceo-Chemistey of Poisons, we understand 
 the study of the chemical properties of poisons as revealed by 
 the aid of the microscope. Although the scope of the present 
 work is not limited to this department of the subject, yet as that 
 branch of the science forms a main element of the treatise, 
 we have designated it by that title. 
 
 The instrument requisite for investigations of this kind may 
 be comparatively simple; and but little accessory apparatus 
 will be required. The stage of the instrument should be suffi- 
 ciently large to receive a watch-glass having a diameter of not 
 less than two inches. Object-glasses of only low power are 
 usually required. Very often an amplification of from thirty 
 to forty diameters will answer the purpose best, but more fre- 
 quently, perhaps, a power of about seventy-five wiU be the 
 most satisfactory, while in some few instances an amplifica- 
 tion of about two hundred and fifty will be required. The 
 objectives best suited for these powers are the inch and a half, 
 two-thirds inch, and one-fifth inch, respectively. In these in- 
 vestigations, as in all others with the microscope, the lowest 
 amplification that will reveal the true character of the object 
 
34 INTRODUCTION. 
 
 examined, will be the most satisfactory. A polarizing appa- 
 ratus will sometimes be necessary to determine the true nature 
 of an object ; and in some instances a micrometer will be found 
 useful to ascertain the absolute size of the object. 
 
 In applying the microscope to the examination of the result 
 of a chemical reagent upon a suspected solution, a single drop 
 of the liquid, placed in a watch-glass or upon a glass slide, is 
 treated with a very small quantity of the reagent, added by 
 means of a pipette, and the mixture, with as little agitation as 
 possible, transferred to the stage of the instrument. If, as is 
 sometimes the case, the crystalline deposit produced by the 
 reagent be readily broken up by agitation, the watch-glass 
 containing the drop of fluid to be examined, is placed on the 
 stage of the instrument before the addition of the reagent. In 
 many instances, as will be noticed hereafter, the formation of a 
 precipitate is much facilitated by stirring the mixture with a 
 glass rod. Should the mixture evolve fumes injurious to the 
 object-glass, a flat watch-glass having a ground edge is selected, 
 and this covered by a piece of very thin glass. Any special 
 directions in regard to the use of this instrument, wiU be pointed 
 out hereafter, as occasion may require. 
 
 A Poison is any substance which, when introduced into the 
 body and being absorbed, or by its direct chemical action, or 
 when applied externally and entering the circulation, is capable 
 of producing deleterious effects. There is no doubt but all 
 poisons are to a greater or less extent absorbed into the cir- 
 culation. In fact, with most of them this is certainly a condi- 
 tion essential to the production of their effects; yet it would 
 appear that in the action of some substances, which produce 
 local chemical changes, death, in some instances at least, can 
 only be referred to the effects of the changes thus produced. 
 The mineral acids and caustic alkalies are the principal poisons 
 which have a direct chemical action upon the parts with which 
 they are brought in contact. This action is due to a mutual 
 affinity existing between the agent and the tissue. In this 
 respect, the action of these substances differs from that of cer- 
 tain heated liquids, such as boiling water, which are inert at 
 ordinary temperatures, but which, simply on account of their 
 
CAUSES MODIFYING THE ACTION OF POISONS. 35 
 
 condition, induce a chemical change in the part to which they 
 are applied, without themselves being chemically concerned in 
 the change. When applied externally, some poisons are ab- 
 sorbed by simply being brought in contact with the unbroken 
 skin; whilst others do not enter the circulation unless applied 
 to an abraded or wounded surface. 
 
 Poisons diiFer greatly in regard to the quantity necessary to 
 prove injurious. Thus the fiftieth part of a grain of aconitine 
 has seriously endangered the life of an adult, while on the 
 other hand, an ounce of sulphate of magnesia may generally 
 be administered with impunity; yet in large quantities the 
 latter substance has in several instances caused death, and is 
 strictly a poison, although not commonly reputed as such. As 
 yet we know of no substance that is poisonous in all propor- 
 tions. Any of the most powerful poisons may be administered 
 in certain quantities without producing any appreciable effect, 
 and most of them may be so employed as to constitute valuable 
 remedial agents. 
 
 In medico-legal inquiries, the leading idea connected with 
 the term poison, is whether the given results are directly 
 traceable to the substance and the intention with which it 
 was employed. 
 
 Poisons not only differ from each other in regard to the 
 quantity necessary to destroy life, but the effects of the same 
 substance may be much modified by circumstances, and even 
 substances which to most persons are harmless may, on ac- 
 count of certain peculiarities of constitution, produce deleteri- 
 ous effects. 
 
 Causes which modify the effects of Poisons. — Among the 
 causes which may modify the effects of poisons, may, in thig 
 connection, be mentioned Idiosyncrasy, Habit, and a Diseased 
 State of the System. 
 
 1. Idiosyncrasy, or a peculiarity of constitution, may vari- 
 riously modify the effects of substances. Thus to some persons 
 ordinary medicinal doses of certain drugs, such as opium or 
 mercury, produce violent symptoms, and even death. In other 
 instances, substances which to most persons are harmless, and 
 even ordinary articles of food, produce symptoms of irritant 
 
 3» 
 
36 INTRODUCTION. 
 
 poisoning. This has been observed in the eating of certain 
 kinds of fish, honey, pork, veal, and mutton. In still another 
 form of idiosyncrasy, there is a diminished susceptibility to the 
 action of certain substances, which to most persons are active 
 poisons. This peculiarity of constitution is very rare, and is 
 most generally observed in regard to the action of mercury and 
 opium. Dr. Christison relates an instance, in which a gentle- 
 man, unaccustomed to the use of opium, took without injury 
 nearly an ounce of good laudanum. 
 
 2. Habit may render certain poisons harmless in doses, 
 which to most persons would prove rapidly fatal. The influ- 
 ence of habit is daily seen in the use of opium, tobacco, and 
 alcohol; and it is well known that certain other agents when 
 administered medicinally, in frequently-repeated doses, after a 
 time lose their ordinary effects. Persons accustomed to the use 
 of opium, have taken daily, for long periods together, quan- 
 tities of laudanum that would prove fatal to several persons 
 unaccustomed to its use. Although this influence has princi- 
 pally been observed, as remarked by Dr. Christison, in regard 
 to the action of certain organic poisons, especially such as act 
 on the brain and nervous system; yet it seems now to be fully 
 established that certain persons in Styria accustom themselves 
 even to the eating of arsenic in doses of several grains daily, 
 and continue the practice for many years without experiencing 
 any of the usual effects of the poison. The statements formerly 
 made by Dr. Tschudi and others in regard to the existence of 
 this practice, have been discredited by most writers on toxi- 
 cology; but the accounts more recently published by Dr. Ros- 
 coe, as quoted by Dr. Taylor (Med. Jur., Amer. ed., 1861, 
 p. 693), and the direct observations of Dr. Maclagan, of Edin- 
 burgh (Chemical News, London, July, 1865, p. 36), while on 
 a visit to Styria, seem to leave no doubt whatever of its ex- 
 istence. In one of the cases observed by Dr. Maclagan, the 
 individual, a muscular young man, aged twenty-six years, 
 swallowed in connection with a very small piece of bread, five 
 grains of genuine powdered arsenious acid, or white arsenic, 
 which he stated was about the quantity he was in the habit of 
 taking twice a week. In the urine passed by this individual 
 
CLASSIFICATION OF POISONS. 37 
 
 two hours afterward, as also in that passed after twenty-six 
 hours, Dr. Maclagan detected a very notable quantity of arsenic. 
 It is but proper to observe, that the experience of most medical 
 practitioners in the use of this substance, does not accord with 
 the results of this Styrian practice. 
 
 3. Disease. — In certain diseased conditions of the system, 
 there is a dimiaished susceptibility to the action of certain 
 poisons; whilst in others, there is an increased susceptibility, 
 even to the action of the same substance. Thus in tetanus, 
 hydrophobia, mania, and delirium tremens, quantities of opium, 
 which in ordinary states of the system would be fatal, may often 
 be administered with beneficial effects. In a case of tetanus 
 related by Dr. Watson (Practice of Physic), something over 
 four ounces of laudanum were taken on an average daily, for 
 twenty days; after which the patient recovered. The same 
 writer quotes another instance of the same affection, in which 
 an ounce of solid opium was taken, in divided doses, daily, for 
 twenty-two days. So also, in inflammation of the lungs, enor- 
 mous doses of tartar emetic have been given with advantage. 
 On the other hand, in cases in which there is a predisposition 
 to apoplexy, an ordinary dose of opium may cause death. In 
 like manner, in certain diseases, there is an increased suscepti- 
 bility to the action of mercury and other mineral substances. 
 
 Classification of Poisons. — Most recent writers on this 
 subject have adopted the arrangement of poisons, according to 
 the symptoms they produce, into three classes, namely. Irri- 
 tants, Narcotics, and Narcotico-Irritants. Since, however, 
 there are many poisons, the effects of which are subject to 
 great variation, and others which according to their ordinary 
 effects, might with equal propriety be placed in one or another 
 of these classes, this classification is open to objection; never- 
 theless, it is, perhaps, the best, for practical purposes, yet 
 proposed. 
 
 Irritant Poisons, as a class, produce irritation and inflam- 
 mation of the stomach and bowels, attended or followed by 
 intense pain in these parts, tenderness of the abdomen, and 
 violent vomiting and purging, the matters evacuated being often 
 tinged with blood. Some of the members of this class, such as 
 
38 INTRODUCTION. 
 
 the mineral acids and caustic alkalies, also possess corrosive 
 properties, and accordingly occasion, in addition to the effects 
 just mentioned, more or less disorganization of the mouth, 
 throat, oesophagus, and stomach. The action of these sub- 
 stances, if not too dilute, is immediate, and is attended with a 
 sense of burning heat in the parts with which they come in 
 contact. When highly diluted, any of the corrosive poisons 
 may act by simply iaducing irritation and inflammation. 
 
 The irritant poisons may be divided into three sections, 
 according to the kingdom of nature to which they belong, 
 namely, mineral, vegetable, and animal. The first section is 
 much the largest, and embraces, with the exception of some 
 gaseous substances, all strictly inorganic poisons. Gamboge 
 and cantharides, are, respectively, examples of the second and 
 third sections. 
 
 Narcotic Poisons are such as act principally on the brain 
 and spinal ruarrow, more especially on the former. They 
 induce headache, vertigo, stupor, , impaired vision, delirium, 
 insensibility, paralysis, convidsions, and coma. This class con- 
 tains comparatively few substances, the principal of which are 
 Opium and Hydrocyanic acid. Several of the poisonous gases 
 belong to this class. 
 
 Naecotico-Ireitants partake, as indicated by their name, 
 of the action of both the preceding classes. Thus, they may 
 produce, as a result of their irritant action, nausea, pain in the 
 stomach, vomiting, and purging; and as a result of their action 
 on the nervous system, stupor, delirium, paralysis, coma, and 
 convulsions. Some of them, however, do not usually produce 
 well-marked symptoms of irritation; and all of them produce 
 their most marked effects on the nervous system. A few, such 
 as strychnine and brucine, act chiefly on the spinal cord, and 
 produce violent tetanic convulsions, without any other prom- 
 inent symptom. AU the members of this class, which is quite 
 numerous, are derived from the vegetable kingdom. 
 
 In referring the symptoms in a given case to the action of 
 either of the above classes, it must not be forgotten, as already 
 intimated, that the members of each do not always produce the 
 same effects. Thus arsenic has occasioned symptoms similar to 
 
SYMPTOMS AS EVIDENCE OF POISONING. 39 
 
 those of narcotic poisoning; whilst opium has produced effects 
 resembKng poisoning by an irritant. 
 
 Sources of Evidence of Poisoning. 
 
 The medical evidence in cases of poisoning, is derived 
 chiefly from — 1. The symptoms; 2. The post-mortem appear- 
 ances; and, 3. Chemical analysis. 
 
 1. Evidence from the Symptoms. 
 
 In forming an opinion in a case of suspected poisoning, the 
 medical examiner should acquaint himself with, not only the 
 special character of the symptoms present, but also, as far as 
 practicable, the previous health and habits of the patient, when 
 food or drink was last taken, whether in taking it any peculiar 
 taste or odor was observed, and whether others partook of the 
 same food. 
 
 Among the characters of the symptoms of poisoning usually 
 mentioned by writers on this subject, the most constant are — 
 1. The symptoms arise suddenly, and soon after the taking of 
 food, drink, or medicine; and, 2. They rapidly prove fatal. 
 
 1. The symptoms occur suddenly, and soon after the talcing of 
 some solid or liquid. — The greater number of poisons, when 
 taken in fatal quantity, manifest their action either immediately 
 or within a short period, the symptoms of but few being de- 
 layed, under ordinary circumstances, much beyond an hour. 
 Many instances might be cited, in which a knowledge of the 
 time that elapsed between the taking of food or drink and the 
 appearance of the suspected symptoms, was in itself sufficient to 
 determine that they were really due to natural causes and not 
 to the effects of poison. In considering this relation, however, 
 it must not be overlooked that the interval between the taking 
 of a poison and the first appearance of symptoms, not only 
 varies with each substance, but the time, as well as the char- 
 acter of the symptoms of the same poison, may be more or 
 less affected by circumstances, such as quantity, the state in 
 which administered, condition of the stomach, combination 
 
40 INTRODUCTION. 
 
 with other substances, and, as already mentioned, a diseased 
 state of the system. Thus strychnine, when taken in fatal 
 quantity, has produced violent symptoms within five minutes 
 afterwards, and they usually appear within thirty minutes, yet 
 they have been delayed, in one instance at least, for two hours 
 and a half. It is well known that antimony, arsenic, lead, and 
 various other poisons, when taken into the system ia repeated 
 small doses, may give rise to eifects wholly different from those 
 usually produced by a single poisonous dose of the substance. 
 As a general rule, pois.ons act more speedily when taken 
 in the state of solution than in the solid form. On the other 
 hand, a full stomach, and, according to Dr. Christison, sleep, 
 may delay the action of certain substances. That the action 
 of one poison may be modified by the presence of another, is 
 well illustrated by the following case. A man, aged twenty- 
 nine years, swallowed three grains of strychnine, one drachm 
 of opium, and an indefinite quantity of quinine. When seen 
 by a physician twelve hours afterwards, he only complained of 
 feeling "queer." But there was extreme cerebral excitement; 
 the pulse quick, full and strong; pupils contracted; the whole 
 face of a deep-red color ; tongue tremulous and covered with a 
 brownish-white fur; surface of the body hot, with profuse per- 
 spiration; body and limbs in violent tren^or, and at intervals 
 spasmodic action of all the muscles, alternating with compara- 
 tive quiet and drowsiaess, from which he was easily roused. 
 Upon the administration of full emetic doses of sulphate of 
 zinc, opium was freely ejected. One hour later, the patient 
 became quite drowsy, but when roused would start violently 
 and remain delirious for some minutes. In two hours more, 
 complete stupor suddenly supervened and continued, with but 
 little change till death, which occurred forty hours after the 
 mixture had been taken. (Chicago Medical Journal, Novem- 
 ber, 1860.) How far the first appearance and character of 
 the symptoms of a particular poison may depart from their 
 ordinary course, can be learned only from a comparison of 
 well-authenticated cases. In this respect, our knowledge at 
 present in regard to the eifects of very many substances, is 
 extremely limited, and there is no reason to believe that in 
 
SYMPTOMS AS EVIDENCE OF POISONING. 41 
 
 regard to any, we have as yet met with the greatest deviation 
 possible. 
 
 In this connection, it must also be borne in mind that there 
 are certain natural diseases, the symptoms of which resemble 
 more or less those of poisoning, and which may appear sud- 
 denly at any time. In fact, some of these diseases, such as 
 apoplexy and perforation of the stomach, are more likely to 
 occur soon after the taking, of food than at any other period. 
 Instances of this kind, however, are of rare occurrence, and 
 the subsequent history of the case will usually enable the prac- 
 titioner to determine without difficulty its true nature. Nev- 
 ertheless, cases have occurred, the nature of which could only 
 be established by the post-mortem appearances and chemical 
 analyses. 
 
 When two or more persons, who have eaten of the same food, 
 are suddenly seized with violent symptoms, there is, of course, 
 increased reason for suspecting the presence of a poison. This 
 circumstance has in some instances at once revealed the source 
 of the poison. Results of this kind, however, may be due to 
 an unwholesome or diseased condition of the food; or to its 
 having accidentally become contaminated with a poisonous 
 metal, such as copper, lead, or zinc, during its preparation. 
 On the other hand, several persons may partake of the same 
 meal, or even of the same food, and poison have been design- 
 edly introduced only into the portion intended for a particular 
 individual. Thus in a case in which we were recently con- 
 sulted, and which will be referred to hereafter, a family of sev- 
 eral persons having mush and milk for supper, the mush was 
 placed on the table in one dish, while the milk was distributed 
 at the usual places of sitting, in bowls. Into one of the bowls 
 strychnine had been introduced, and its intensely bitter taste 
 was, perhaps, the only circumstance that saved the life of the 
 person for whom it was intended; only, however, to become 
 the victim a few days afterwards of a fatal quantity, under a 
 form in which its taste was entirely concealed. In another 
 instance, the plnm-pie served for dinner was furnished to the 
 several members of the family, on separate plates; under the 
 crust of one of the pieces, arsenic had been placed, and proved 
 
42 INTRODUCTION. 
 
 fatal to the person who ate it. From what has already been 
 stated, it is obvious that several persons may even partake of 
 the same poisoned food, and the results be very different. Dr. 
 Beck quotes several striking examples of this kind.. 
 
 Lastly, in inquiries of this kind it must be remembered 
 that poisons may be introduced into the system in other ways 
 than with food, drink, or medicine. Thus poisoning by the ex- 
 ternal appKcation of the substance, is not of unfrequent occur- 
 rence ; the same is also true of the inhalation of certain vapors 
 and gases. Instances of this kind, however, are usually the 
 result of accident. Several instances are recorded, in which 
 poisons were criminally introduced into the rectum and vagina; 
 and Dr. Christison cites a case, in which a fatal quantity of 
 sulphuric acid was poured into the mouth of an individual 
 while asleep. 
 
 2. The symptoms rapidly rim their course. — The duration of 
 the symptoms of poisoning, like their appearance, is subject to 
 great variation, even with regard to the same substance. Some 
 few poisons, as hydrocyanic acid, nicotine, and conine, usually 
 prove fatal within a few minutes, and most of them within com- 
 paratively short periods. Yet, as just intimated, great differ- 
 ences have been observed even in regard to the action of the 
 same substance. Thus the fatal period of hydrocyanic acid 
 has been protracted for several hours; whilst, on the other 
 hand, arsenic, which on an average perhaps, does not prove 
 fatal in less than twenty-four hours, has caused death in less 
 than two hours. As a general result, a large dose of a given 
 substance will prove more rapidly fatal than a small one, yet 
 this is by no means always the case. Half a grain of strych- 
 nine has caused the death of an adult in less than twenty 
 minutes, while in a case in which between five and six grains 
 were taken, death was delayed for six hours; and, even larger 
 quantities than the last mentioned have been followed by 
 recovery. 
 
 The vegetable poisons as a class, usually, either prove fatal 
 within at most a very few days, or the patient entirely recovers ; 
 but many of the mineral substances do not unfrequently cause 
 death until after the lapse of several days. In fact, many of the 
 
SYMPTOMS AS EVIDENCE OF POISONING. 43 
 
 members of the latter class, may give rise to secondary effects, 
 which may extend through an interval of many weeks, or even 
 months. The usual period within which each of the more com- 
 mon poisons proves fatal, and how far it has departed from its 
 ordinary course, will be pointed out hereafter in the special 
 consideration of the individual substances. 
 
 In considering the duration of the symptoms in a case of 
 suspected poisoning, it must be remembered that the symptoms 
 of some natural diseases, not only closely resemble those of cer- 
 tain kinds of poisoning, but also run their course with equal 
 rapidity. In most instances, however, a careful examination of 
 the symptoms, with a full history of the case, when this can be 
 obtained, will enable the medical practitioner to form a correct 
 diagnosis; but cases not unfrequently occur the true nature of 
 which can only be established by the post-mortem appearances 
 and chemical analysis. 
 
 The diseases most likely to give rise to symptoms re- 
 sembling irritant poisoning are, cholera, inflammation of the 
 stomach and bowels, and perforation of the stomach; and 
 those that may simulate narcotic poisoning — apoplexy, inflam- 
 mation of the brain, and organic diseases of the heart. Chol- 
 era has been mistaken for poisoning by arsenic, and on the 
 other hand, arsenical poisoning has been mistaken for that 
 disease. The same has also been true in regard to apo- 
 plexy and opium poisoning. The symptoms of disease of 
 the heart, in the rapidity of their action, may closely resemble 
 the effects of hydrocyanic acid and of nicotine. The true na- 
 ture of some of the foregoing diseases is readily revealed upon 
 dissection; but others, like the poisons with whose symptoms 
 they may be confounded, leave no well-marked morbid ap- 
 pearances. 
 
 In the examination of a case of suspected poisoning, the 
 medical attendant should obtain as far as possible a full history 
 of the progress of the symptoms and their relation to the tak- 
 ing of food, drink, or medicine. All suspicious articles of this 
 kind should be collected; and if vomiting has occurred, the 
 matters ejected should also be collected and their character 
 noted. All articles thus obtained should be sealed up, if solid, 
 
44 INTRODUCTION. 
 
 in clean white paper, and if liquid, in clean glass jars, dis- 
 tinctly labeled, and preserved for future examination, the col- 
 lector being careful not to permit any such article to pass out 
 of his possession until delivered to the proper person. 
 
 A chemical examination of soifie of these articles may at 
 once reveal the true nature of the symptoms. It need hardly 
 be remarked, that a failure to discover poison under these cir- 
 cumstances, will by no means be conclusive evidence that a 
 poison had not been taken. On the other hand, the detection of 
 poison in a remnant of food or medicine taken by the person, 
 will not of itself be conclusive proof that a poison had been 
 taken. Symptoms of poisoning have been feigned and poison 
 put into articles of this kind for the purpose of charging another 
 with an attempt to murder. The existence of this fact can, of 
 course, only be determined by the attending circumstances. A 
 few years since we were engaged in a case in this city in which 
 it clearly appeared that a man maliciously put a large quantity 
 of white arsenic into an alcoholic medicine he was using, and 
 actually swallowed sufficient of the mixture to produce serious 
 symptoms; he then charged his wife with the poisoning. 
 
 2. Evidence from Post-mortem Appearances. 
 
 There are but very few instances in which the post-mortem 
 appearances are peculiar to poisoning. Nevertheless, this part 
 of the evidence should always be very carefully considered, for 
 when taken in connection with the symptoms and other circum- 
 stances, it may fully establish the true character of a case, 
 which would otherwise be doubtful. In death from natural dis- 
 ease, a post-mortem examination may at once discover the fact. 
 However, appearances of ordinary disease may be present, and 
 death have resulted from the effects of poison. Several in- 
 stances, in which coincidences of this kind existed, might be 
 cited. The presence of some few poisons, as opium and hydro- ' 
 cyanic acid, may sometimes be recognised by their odor; and 
 others, when in the stomach, by their color or botanical charac- 
 ters. It is a popular belief, that great lividity of the body and 
 rapid decomposition always attend and are characteristic of 
 
MORBID APPEARANCES OF POISONING. 45, 
 
 death from poisoning; but these results are rarely produced, 
 and are by no means peculiar. 
 
 Some poisons leave no appreciable morbid changes in the 
 dead body; and of those that usually do, the appearances are 
 subject to great variety, and in many instances similar to the 
 eifects of ordinary disease, or even the results of cadaveric 
 changes. The mineral acids and caustic alkalies usually leave 
 the most marked evidence of their action, and in some instances 
 this is quite characteristic. 
 
 The irritant poisops as a class usually produce irritation 
 and inflammation of one or more portions of the alimentary 
 canal, the eifects being sometimes confined to the stomach, 
 while at others they extend to a greater or less extent through- 
 out the entire canal. In some instances the coats of the 
 stomach become ulcerated and softened, and even perforated. 
 Poisons of this class, however, may cause death without leaving 
 any discoverable change in the body. This has been the case 
 even in respect to some of the more acrid and corrosive sub- 
 stances. In several instances of poisoning by arsenic, which 
 generally produces strongly marked appearances in the stomach 
 and bowels, nothing abnormal was found upon dissection. In 
 the minute examination of the tissues of the alimentary canal, 
 M. Baillou advises the inspection to be made under transmit- 
 ted light. 
 
 Narcotic poisons in some instances produce more or, less dis- 
 tention of the veins of the brain, but' in others they leave no 
 marked morbid appearances, and in none are the appearances 
 peculiar. According to Orfila, the lungs almost always present 
 livid and black spots; and their texture is more dense and less 
 crepitant. These appearances, however, may result from ordi- 
 nary causes. In some few instances there has been more or 
 less irritation of the alimentary canal; but this condition was 
 most probably induced by the vehicle in which the poison was 
 taken, or the remedies subsequently administered. 
 
 Narcotico-irritants partake in the nature of their effects of 
 both the preceding classes. Thus, they may produce irritation 
 and even ulceration of portions of the alimentary canal, and 
 congestion of the lungs and of the veins of the brain and its 
 
46 INTRODUCTION. 
 
 membranes. But in most instances, the morbid changes are 
 not well marked. 
 
 The usual morbid changes produced by the individual 
 poisons, will be pointed out hereafter; but in this ponnection 
 may be briefly mentioned some of the appearances which may 
 be equally produced by ordinary disease or cadaveric changes 
 and by poisoning. 
 
 Appearances common to Poisoning and Disease. — Redness of 
 the stomach and intestines as the effect of poisoning, can not in 
 itself be distinguished from that arising from natural disease. 
 This condition is not only frequently the result of active dis- 
 ease; but it has often been observed immediately after death 
 in cases in which during life there were no indications of 
 derangement of the stomach or bowels. Moreover, various 
 pathologists have observed that pseudo-morbid redness of the 
 mucous membrane of the stomach sometimes makes its appear- 
 ance several hours after death. Dr. Christison is of the opinion 
 that an effusion under the villous coat of the stomach, and 
 incorporation with its substance, of dark brownish-black blood, 
 is characteristic of violent irritation, if not of the effects of 
 poison alone. It is well known that colored substances within 
 the stomach, and the contact of this organ after death with the 
 adjacent parts, may cause it to become more or less colored. 
 But these appearances are readily distinguished from the effects 
 of poison. 
 
 Softening of the stomach is another appearance which may 
 give rise to embarrassment. When due to the action of poison, 
 it is usually accompanied by other appearances which readily 
 distinguish it from the effects of ordinary disease or post- 
 mortem changes. Dr. Carswell has shown that this condition 
 is not unfrequently produced by the chemical action of the 
 gastric juice after death. He also observes, that in softening 
 of the mucous membrane of the stomach as the result of inflam- 
 matory action, the tissue is always more or less opake, and the 
 action attended by one or more of the products of this patho- 
 logical state; whereas in post-mortem softening, the tissue is 
 always transparent, and the action never attended with serous 
 effusion or other concomitants of inflammation. 
 
MORBID APPEARANCES OF POISONING. 47 
 
 Ulceration and perforation of the stomach, are not unfre- 
 quently produced by corrosive poisons, but they, especially the 
 latter, are rarely met with as the result of the action of the 
 simple irritants. As the effect of natural disease or post- 
 mortem action, they are not uncommon. In many instances 
 these appearances, as the result of poisoning, can only be dis- 
 tinguished from those arising from other causes, by a history of 
 the symptoms during life, or the detection of poison in the tis- 
 sues or other parts of the body. This distinction is usually well 
 marked in the action of the mineral acids and caustic alkalies. 
 
 Perforation of the stomach has not unfrequently occurred 
 from gelatinisation of its tissues, and in cases in which during 
 life there was no evidence of a diseased state of that organ. 
 These appearances have been chiefly observed in cases of 
 violent or sudden death. It was formerly believed that this 
 condition was always a morbid process, and characteristic of a 
 special disease. But, since the researches of modern patholo- 
 gists have shown that the gastric juice has the property of 
 dissolving the dead stomach, and that many of these lesions 
 have undoubtedly been due to the action of that fluid after 
 death, there is little doubt that they may all be referred to 
 post-mortem changes. When the gastric juice escapes through 
 the aperture thus produced, it may, as has often been the case, 
 exert its solvent action upon the adjacent organs. As these ap- 
 pearances are unattended by signs of irritation, they are 
 usually readily distinguished from the effects of poisoning. 
 Should, however, a perforation of this kind occur in a case in 
 which prior to death the stomach was affected with signs of 
 irritation, it might be impossible from the appearances alone to 
 determine the true character of the perforation. 
 
 Perforation of the oesophagus and of the intestines as the 
 result of poisoning, is not at all likely to occur. In fact, there 
 seems to be only one instance of the former, and none 'of the 
 latter, on record. But these conditions, as the result of disease, 
 have often been observed; and they have even resulted from 
 the action of the gastric juice after death. 
 
 Points to he observed in post-mortem examinations. — All 
 investigations of this kind should be made in the presence of 
 
48 INTRODUCTION. 
 
 the proper law officer; and it is well for the examiner to have 
 the assistance and corroboration of another physician. All 
 appearances observed, whether abnormal or otherwise, should 
 be fully written down at the time of their observance. The 
 length of time the person has been dead ; how long he survived 
 the first symptoms ; and the condition of the body in respect to 
 external appearances, should as far as practicable be learned 
 and carefully noted. In the dissections, the condition of the 
 entire alimentary canal, and of all the organs essential to life, 
 should be minutely examined; in the female, the vagina and 
 uterus should also be inspected. The stomach with its con- 
 tents, and a portion of the small intestines, properly ligatured, 
 should be removed from the body. The condition of these 
 organs, and the nature of their contents, may then be exam- 
 ined. In some instances, however, it is best not to open these 
 organs until they are delivered to the chemist. A portion of 
 the liver and of the blood, should also be removed for chemical 
 analysis. Although some of the poisons may be recovered by 
 chemical analysis from various other portions of the body, as 
 from the spleen, kidneys, heart, and even from the muscles; 
 yet it is rarely necessary to reserve for this purpose, any parts 
 other than those already specified. 
 
 All the organs and the blood thus removed should be col- 
 lected in separate, clean glass vessels, great care being taken 
 that none of the reserved substances at any time be brought in 
 contact with any substance that might afterwards give rise to 
 suspicion. Before passing out of the sight of the examiner, the 
 bottles should bo securely sealed and fully labeled. They 
 should then be retained in his sole possession until delivered to 
 the proper person. 
 
 3. Evidence from Chemical Analysis. 
 
 Importance of chemical evidence. — In most charges of pois- 
 oning, the final issue depends upon the result of a chemical 
 analysis. In fact, in many instances in which the evidence 
 from symptoms, post-mortem appearances and moral circum- 
 stances, is very equivocal or in part wanting, a chemical 
 
VALUE OF CHEMICAL ANALYSIS. 49 
 
 examination may at once determine tte true cause of death. 
 It must be remembered, however, that a person may die from 
 the effects of poison and not a trace of its presence be discov- 
 erable in any part of the body; while on the other hand, the 
 mere discovery of a poison in the food or drink taken or in the 
 body after death, is not in itself positive proof that it occa- 
 sioned death. 
 
 It has been claimed, that a failure to detect poison in the 
 dead body, by proper chemical skill, was evidence that death 
 was the result of some other cause; but this claim is entirely 
 groundless. The symptoms and pathological appearances, at 
 least in connection with moral circumstances, are often suffi- 
 cient in themselves to fally establish death from poisoning; and 
 a number of convictions have very properly been based on 
 these grounds in instances in which chemical evidence was 
 wanting, and even when it had entirely failed. There are a 
 number of organic poisons which at present can not be recog- 
 nised by chemical tests ; and instances are recorded in which 
 death resulted from large quantities of some of the poisons most 
 easy of detection, and not a trace could be discovered in any 
 part of the body. It is obvious that the discovery of minute 
 traces of such poisons as are used medicinally, could not, inde- 
 pendent of symptoms and other circumstances, be regarded as 
 evidence of poisoning. 
 
 Substances requiring analysis. — The substances that may 
 directly become the subject of chemical analysis, in a case of 
 suspected poisoning, are: the pure poison in its solid or liquid 
 state; suspected articles of food or medicine; matters ejected 
 from the body by vomiting or purging; the urine; suspected 
 solids found in the stomach or intestines after death ; the con- 
 tents of the stomach or bowels; any of the soft organs of the 
 body, as the liver, spleen, etc. ; and the blood. 
 
 Sometimes it is only necessary to examine one of the above- 
 mentioned substances; but in many instances, two or more of 
 them require examination. If a poison be thus detected, it 
 will sometimes become necessary to examine substances other 
 than those specified, in order to determine its real source. The 
 evidence of poisoning is, of course, most complete when the 
 
 4 
 
50 INTRODUCTION. 
 
 poison is recovered from some of the soft organs of the body, 
 after it has been absorbed. So also, the proof will be more 
 direct when the poison is detected in the contents of the 
 stomach or intestines, than in articles of food or medicine. 
 
 Precautions in regard to analyses. — When called to make a 
 chemical examination of any suspected material, the analyst 
 should obtain, as far as practicable, a knowledge of the symp- 
 toms, and, if death has taken place, of' the post-mortem ap- 
 pearances, observed in the suspected case: since these, when 
 known, wUl generally enable him to decide at least to which 
 class of poisons the substance belongs, and in some instances 
 wiU even indicate with considerable certainty the individual 
 substance. He may thus, by following these indications in the 
 analysis, save much labor, and — which in many instances is of 
 much more importance — be enabled to fully establish the pres- 
 ence of poison when present in quantity too minute to be rec- 
 ognised under other circumstances. It must not be forgotten, 
 however, that irritant poisons have produced symptoms resem- 
 bling those induced by some of the narcotics, and that the lat- 
 ter may produce symptoms of irritant poisoning. 
 
 So also, before applying any chemical test to a suspected 
 solid or liquid, its quantity — of the former by weight and of the 
 latter by measure — should be accurately determined. In the 
 application of the reagents, the very least quantity of the ma- 
 terial that will answer the purpose, should, at least at first, be 
 employed for each test. In like manner, in the preparation of 
 complex mixtures, the residual solution should be reduced to 
 the very smallest volume compatible with the application of the 
 tests that it may become necessary to apply. There is little 
 doubt, that in many of the reported instances of non-detection 
 of poisons, the failures have resulted from a neglect of this 
 point. It should always be borne in mind, that a given quan- 
 tity of a poison, when in solution in a small quantity of fluid, 
 may yield with a given reagent, perfectly characteristic results; 
 whereas if the solution be but slightly more dilute, the reaction 
 may entirely fail. Thus, the hundredth part of a grain of nico- 
 tine in one grain of water, yields with bichloride of platinum, 
 a copious and rather characteristic crystalline precipitate, while 
 
VALUE OF CHEMICAL ANALYSIS. 51 
 
 the same quantity in ten grains of that liquid yields no precip- 
 itate whatever. 
 
 In the preparation of the contents of the stomach and of 
 the solid organs of the body, it is often advisable to employ 
 only about one-half or two-thirds of the matter for the first 
 examination. This proportion will perhaps in all cases, at 
 least in regard to mineral poisons, suffice to show the poison if 
 present, while in case of accident, the analysis could be 
 repeated. When, however, the analyst has perfect confidence 
 in his ability to go safely through with the examination, it is 
 perhaps best not to make this division of matter, at least in the 
 investigation for certain organic poisons. The minute quantity 
 of poison usually taken up by the blood, especially in the case 
 of the alkaloids, renders it necessary to operate upon compara- 
 tively large quantities of this fluid, and to conduct the exam- 
 ination with extreme care. 
 
 When the symptoms or attending circumstances do not point 
 to a particular poison or at least to the class to which it belongs, 
 it is obvious that a division of the matter submitted for exam- 
 ination becomes absolutely necessary. Under these circum- 
 stances, great care should be exercised not to subject the matter 
 to any process that would preclude the possibility of examining 
 for any poison for which it might afterwards become necessary 
 to look. 
 
 It need hardly be observed that during investigations of this 
 kind, the examiner should never lose sight of the suspected 
 material, except when it is in some secure place; and the 
 greatest possible care should be taken that it is not brought in 
 contact with any substance the nature of which is not fully 
 understood. A neglect of these directions may prove fatal to 
 the results of a chemical examination. The careful analyst 
 need not be cautioned against hasty conclusions in regard to the 
 behavior of reagents. 
 
 After the presence of a poison is fuUy established, it is in 
 most instances only necessary to be able to state the probable 
 amount present; but sometimes it is necessary to determine its 
 exact quantity. In all cases in which it is practicable, it 
 is best to determine the actual amount recovered; but it not 
 
52 INTRODUCTION. 
 
 unfrequently occurs, especially in the detection of absorbed 
 poison, that the quantity present is so small as not to admit 
 of a direct quantitative analysis. Under these circumstances, 
 we may often, by accurately noting the volume of solution 
 obtained and observing the comparative reaction of several 
 tests, estimate very closely the strength of the solution, and 
 from this deduce within narrow limits the amount of the poison 
 present. 
 
 It was formerly claimed that unless a quantity of poison suf- 
 ficient to destroy life was found in the dead body, the chemical 
 evidence of poisoning was defective. But it is now a well- 
 known fact, that a person may die from the effects of a large 
 dose, and very little or even not a trace of the noxious agent 
 remain in the body at the time of death. As any of the poison 
 remaining in its free state in the stomach at the time of death, 
 has had no part in producing the fatal result, it is obvious that 
 to recover a fatal quantity from that which had been absorbed, 
 and which was really the cause of death, even granting that 
 none had been eliminated from the body with the excretions, 
 would require an analysis of the entire body and the recovery 
 of every atom of the poison, from that complex mass — the first 
 of which is impracticable ' and the second impossible. It is 
 only, therefore, in cases' in which more than a fatal dose 
 remains in the body at death, that we are able to recover suf- 
 ficient to destroy life. Moreover, as already intimated, the 
 amount of poison in the body at death, is in itself no index 
 whatever of the actual quantity :taken. 
 
 Value of individual chemical Tests. — The result of a chem- 
 ical examination wUl depend, at least in a great measure, upon 
 how far we are acquainted with reactions peculiar to the sub- 
 stance under consideration ; the delicacy of these reactions ; and 
 in many instances, our ability to separate the substance from 
 foreign matter. There is usually no difiiculty in recognising 
 the presence of any of the mineral poisons, even when present 
 only in minute quantity; but the case is very diiferent in re- 
 gard to the detection of many of the organic poisons. For the 
 recognition of many poisons, we are at present familiar with 
 several tests, the reaction of each of which is characteristic 
 
VALUE OF CHEMICAL ANALYSIS. 53 
 
 of the substance; while for the detection of others we are 
 acquainted with only one such reaction; there are others still, 
 for which we have no specific reagent, but whose presence 
 can be fully established by the concurrent result of several 
 tests ; lastly, there are some organic poisons for the detection 
 of which, at present, there is not even known any combination 
 of chemical reactions by which they can be detected. Some 
 of the poisons of the last-mentioned class, may, in the form of 
 leaves, seeds or roots, be recognised by their botanical char- 
 acters; and others, by their pecidiar physiological effects, espe- 
 cially when these are taken in connection with some of their 
 general chemical properties. Among the poisons that can be 
 readily detected when in their pure state, there are some which 
 when present, even in quite notable quantity, in complex 
 organic mixtures, adhere so tenaciously to the foreign organic 
 matter, that it is difficult or impossible to separate them in a 
 state sufficiently pure to determine their presence. 
 
 For the detection of all the poisons considered in the pres- 
 ent volume, with the exception of aconitine, we are acquainted, 
 under certain conditions, with one or more special chemical 
 reactions; and most of them, especially by the aid of the 
 microscope, can now be recognised with absolute certainty, and 
 even separated from complex organic mixtures, in quantities 
 which not long since would have appeared perfectly fabulous. 
 Thus, at present we can recognise by chemical means, when in 
 its pure state, the presence of the 10,000th part of a grain, and 
 in some instances even less, of either arsenic, mercury, strych- 
 nine, hydrocyanic acid, or atropine, with absolute certainty. 
 It does not however follow, that quantities as small as these 
 when present in complex mixtures can be recovered and their 
 nature then established. It is a popular idea, and indeed a 
 very fair inference from the statements of some writers, that 
 the quantity of a substance that can be recognised by chemical 
 means in its pure state, represents that which can be detected 
 under all circumstances. But this is a great error, since the 
 quantity that can thus be recognised and the amount necessary 
 to be present in a complex mixture to enable us to separate 
 that quantity, may differ many hundreds and even thousands of 
 
54 INTRODUCTION. 
 
 times: the difference usually being in proportion to the com- 
 plexity of the mixture. 
 
 From what has already been stated, it is obvious that in 
 determining the nature of a suspected substance, it is not 
 enough that it yields affirmative reactions with a given number 
 of reagents ; but we must know that one or more of these taken 
 singly or two or more of them taken in connection, are peculiar 
 to the substance. Thus aconitine can be precipitated by sev- 
 eral different reagents, yet none of these reactions taken singly 
 nor several of them taken in connection, when obtained from 
 small quantities of organic mixtures, will fully establish the 
 presence of this alkaloid, since there are many other organic 
 substances which yield similar results. We have, however, 
 for the detection of this poison, a delicate and characteristic 
 test in its peculiar physiological effects. Again, morphine 
 yields certain results with several different reagents, yet neither 
 of these taken singly, when obtained from small quantities of 
 amorphous organic mixtures, is characteristic of this poison; 
 but the concurrent action of two or more of them wiU fully 
 establish its presence, since there is no other substance known 
 that possesses these several properties in common with mor- 
 phine. When, however, we have even a very minute quantity 
 of this poison in its crystalline state, then one or more of these 
 tests taken singly, may be characteristic, since most of the fal- 
 lacious substances are uncrystallisable. It frequently happens 
 that a test of this kind is applied under conditions in which the 
 substance having reactions similar to that of the suspected sub- 
 stance could not be present, when, of course, an affirmative 
 reaction is specific. 
 
 The true nature of a reaction that is common to several 
 substances, can in some instances be readily determined by 
 means of the microscope. Thus, a solution of nitrate of silver, 
 when exposed to several different vapors, becomes covered with 
 a white film ; but hydrocyanic acid is the only one in the action 
 of which the film is crystalline, and this is characteristic even 
 with the reaction of the 100,000th part of a grain of the acid. 
 A substance may yield a peculiar crystalline precipitate at one 
 degree of dilution, while at another, the precipitate may not be 
 
VALUE OF CHEMICAL ANALYSIS. 55 
 
 characteristic, as illustrated in the action of bromine with 
 atropine, which yields from one grain of a 20,000th or stronger 
 pure solution, a specific crystalline deposit, while from solutions 
 but little more dilute, the result is not peculiar. 
 
 So also, the true nature of a reaction, may in some instances 
 be determined by submitting the result to a subsequent test. A 
 slip of clean copper, when boiled in a hydrochloric acid solution 
 of either arsenic, mercury, antimony, or of several other metals, 
 becomes coated with the metal; but when the coated copper is 
 heated in a reduction-tube, arsenic is the only substance that 
 will yield a sublimate of octahedral crystals, and mercury the 
 only one that will furnish metallic globules. Some tests can be 
 successfully applied only to comparatively pure solutions, whilst 
 others can be thus applied to very complex mixtures. The 
 copper test for arsenic and mercury, just mentioned, yields in 
 many instances much the same results with complex mixtures 
 as with pure solutions. But this result, is true only in regard 
 to a few tests for the detection of mineral substances. 
 
 In examining a suspected substance or solution, it is usually 
 best, especially when the quantity of material is limited, to be- 
 gin with the most characteristic test, after which if it produces 
 an afiirmative result, one or more corroborative tests should be 
 employed. In many instances, the positive reaction of a, single 
 test, obtained from even a very small fractional part of a grain 
 of the poison, may in a chemical point of view, be as con- 
 clusive of its presence, as the result of any number of tests 
 applied to any quantity of the substance however great. Yet, 
 for medico-legal purposes, it is always best, if sufficient material 
 be at hand, to confirm the results by several tests, and when 
 practicable, show the presence of the poison by two or more 
 independent methods. 
 
 If any of the corroborative tests thus applied, should fail, 
 we should be able to account for the failure. This may be due 
 to want of delicacy on the part of the reagent or the presence 
 of some substance, such as a free acid, an alkali or other for- 
 eign matter, which prevents its normal action. For the same 
 reason, if the test first applied should fail, we should be cautious 
 in concluding the entire absence of poison, unless we are fuUy 
 
56' INTRODUCTION. 
 
 acquainted with the conditions under which the test was applied. 
 Thus it has just been stated, that copper becomes coated with 
 arsenic when boiled in a mixture of that metal and hydrochloric 
 acid, but we may have an impure mixture of this kind in which 
 the metal will not be deposited, even when present in large 
 quantity. In fact, here is no test that wiU produce with a 
 given substance, the same results under all conditions. In the 
 special consideration of the individual tests, the conditions under 
 which they may fail, as weU as the fallacies to which they are 
 liable, and the limit of each for pure solutions, will as far as 
 practicable be pointed out. 
 
 The behavior of a test the reaction of which taken alone has 
 no positive value, is often important in directing the application 
 of other tests. A solution of iodine produces a distinct reaction 
 even with the 100,000th part of a grain of strychnine, when in 
 solution in one grain of water ; yet as this reaction is common 
 to most of the alkaloids and other organic substances, the mere 
 production of a precipitate would not establish the presence of 
 the alkaloid in question. Should, however, this test under 
 proper conditions fail, it would foUow that the suspected solu- 
 tion did not contain even the 100,000th part of its weight of 
 the alkaloid, and therefore that it would be useless to apply any 
 less delicate test for this poison to the solution. 
 
 Failure to detect a poison. — Numerous instances are reported 
 in which persons died from the effects of poison, and none was 
 discovered by chemical analysis in the body after death. This 
 result has most frequently been observed in poisoning with 
 organic substances, but it has happened when mineral poisons, 
 and even those which are most easily detected by chemical 
 tests, had been taken in large quantity. 
 
 A failure of this kind, may be due to any of the following 
 circumstances : 1 . The poison may have been one of the organic 
 substances which can not at present be recognised by chemical 
 tests. 2. The quantity present in the part examined may have 
 been so minute as under the circumstances not to admit of re- 
 covery, or at least in a state sufficiently pure to permit its true 
 nature to be established. 3. It may have been removed from 
 the stomach and intestines, by vomiting and purging or by 
 
VALUE OF CHEMICAL ANALYSIS. 57 
 
 absorption. 4. The absorbed poison may have been carried out 
 of the system with the excretions. 5. If volatile, like hydro- 
 cyanic acid and some few other poisons, it may have been dis- 
 sipated in the form of vapor. 6. It may have undergone a 
 chemical change in the living body, or, especially if of organic 
 origin, have been decomposed in the dead body if far advanced 
 in putrefaction. 
 
 The period in which a poison may be entirely expeUed from 
 the stomach by vomiting, is subject to great variation. Dr. 
 Christison cites two instances of poisoning by arsenic, in which 
 death ensued under much vomiting in five hours, and ia one of 
 which none of the poison could be detected either in the eon- 
 tents or tissue of the stomach, and in the other, only the fif- 
 teenth part of a grain was recovered. In two other instances 
 of like poisoning, in which death took place in eight hours, 
 after one ounce and nearly two ounces respectively, had been 
 taken, not a trace of the noxious agent was discovered in the 
 stomach. On the other hand, Orfila mentions a case, in whjch 
 arsenic was detected in the contents of the stomach of an indi- 
 vidual who had vomited almost incessantly for two entire days. 
 And in a case which we examined not long since, in which 
 there had been almost incessant vomiting for thirty-two hours, 
 forty-two grains of the same poison were recovered; it having 
 been taken in the form of "fly-powder," and much of it existing 
 in the solid state attached to the mucous membrane of the organ. 
 
 Similar results have been observed in regard to the removal 
 of poison from the stomach and bowels by absorption, even in 
 cases in which there was neither vomiting nor purging. Com- 
 paratively large quantities of some of the organic poisons, have 
 apparently thus disappeared within a very few hours. In a 
 case of poisoning by strychnine, in which about six grains had 
 been taken and death ensued in six hours, most careful anal- 
 yses, by Dr. Reese, of Philadelphia, of the contents of the 
 stomach, and of a portion of the small intestines, failed to 
 reveal the presence of a trace of the poison. So also, in a case 
 of poisoning by not less than two ounces of laudanum. Dr. 
 Christison failed to detect morphine in the contents of the 
 stomach, although the person survived the taking of the poison 
 
58 INTRODUCTION. 
 
 only five hours. Some of the mineral poisons may remain in 
 the contents of the living stomach and intestines for several 
 days. Thus Dr. Q-eoghegan found arsenic in the contents of the 
 colon after twelve days. 
 
 After a poison has been absorbed and carried into the tis- 
 sues of the body, it is sooner or later eliminated from the body 
 with the different excretions, more especially with the urine. 
 Many instances are recorded in which death took place with 
 the usual rapidity from the eifects of large doses of the most 
 easily detected mineral poisons, and there was a failure to dis- 
 cover the poison in any part of the body. Orfila concluded 
 from his investigations, that arsenic, mercury, and the mineral 
 poisons generally, were under ordinary circumstances, entirely 
 eliminated from the living system, in about fifteen days, and 
 this view has been sustained by the observations of others. 
 The period of entire elimination, however, is subject to consid- 
 erable variation: it has been limited to a few days, while on 
 the other hand, some of the mineral poisons have been detected 
 in the urine so long as three weeks and even longer, after they 
 were taken into the stomach. 
 
 There is no longer any doubt that the vegetable poisons, 
 such as the alkaloids, enter the blood by absorption, in part at 
 least, in their unchanged state, and are thus conveyed to the 
 tissues; but hitherto there has generally been a failure to 
 recover them from the blood and tissues, even under apparently 
 the most favorable circumstances. We have recovered all the 
 poisons of this class considered in the present treatise, from the 
 blood of poisoned animals, but that they should always be re- 
 covered, even under favorable conditions, from the blood of the 
 poisoned human subject, we wiU not pretend to assert; still, 
 with improved methods of analyses and the aid of the micro- 
 scope, there is little doubt that failures of this kind will become 
 less frequent. 
 
 In regard to the efi'ects of chemical changes and decomposi- 
 tion in removing poison beyond the reach of analysis, it may be 
 remarked that some of the organic poisons, especially when of 
 a volatile nature, may undergo a change of this kind in the 
 dead body after very short periods. In a case of suicide by 
 
CHEMICAL REAGENTS. 59 
 
 hydrocyanic acid, quoted by Professor Casper, no trace of it was 
 found in the stomach twenty-six hours after death, but there was 
 present a considerable quantity of formic acid, as the result of 
 the metamorphosis of the original poison. In like manner, this 
 same poison may be converted into hydrosulphocyanic acid, 
 during the process of putrefaction. So also, phosphorus, by 
 combining with oxygen, is sooner or later converted into one or 
 more of the acid oxides of phosphorus ; this conversion may even 
 be completed in the living body. It need hardly be remarked, 
 that when a chemical antidote has been administered, none of 
 the poison may remain in its uncombined state or the form in 
 which originally taken, in the stomach. 
 
 On the other hand, some of the vegetable alkaloids may 
 remain in their unchanged state in the dead body and other 
 decomposing organic mixtures, for at least some months. Al- 
 though the metallic poisons may undergo chemical changes, even 
 in the living body, yet as the metals themselves are indestructi- 
 ble, the compounds thus produced, may in some instances be 
 recovered even after many years. 
 
 Of chemical reagents. — Only those having practical experi- 
 ence in the matter, know the difScidty of obtaining at least cer- 
 tain reagents and chemicals, in a state of absolute purity. The 
 impurity may in some instances be an ordinary poison and even 
 consist of the very substance suspected to be present in the 
 matters submitted for examination; while in others, it may be of 
 a nature that will very much modify or altogether prevent the 
 normal reaction of the reagent, or give rise to results which may 
 readily be attributed to some other cause. Thus, in one of the 
 methods for the detection of arsenic, the principal chemicals 
 employed are sulphuric acid and zinc, yet that metal is not 
 unfrequently present as an impurity in each of these chemicals. 
 Impurities of this kind, generally consist of inorganic substances, 
 and are chiefly confined to inorganic reagents. Although, under 
 ordinary circumstances, there would be no probability of a re- 
 agent containing any of the organic poisons, such as strychnine, 
 morphine and the like, still an impurity of a reagent used for 
 the detection of any of these poisons, might readily lead to 
 erroneous conclusions. 
 
60 INTRODUCTION. 
 
 The analyst should never accept any reagent or chemical as 
 pure, until he has fully estabhshed its purity for himself; and if 
 there be any possibility of its having become changed since last 
 examined, the examination should be repeated. This latter pre- 
 caution- is necessary since reagents, when frequently used for 
 general analyses, are quite liable to become more or less con- 
 taminated; and some reagents may even speedily undergo spon- 
 taneous changes. AU liquid reagents should be preserved in 
 hard Glerman-glass bottles, and handled only by means of per- 
 fectly clean pipetts. If poured from the mouth of the bottle, it 
 is diificult to control the amount used; and moreover, the portion 
 left adhering to the neck of the bottle, may by the action of the 
 atmosphere, become changed, and afterwards fall back into the 
 solution, and thus contaminate it. It need hardly be added, that 
 no other than perfectly pure distilled water should be used for 
 the solution of reagents, and in aU chemical operations. 
 
 In applying a reagent to a suspected solution, it should be 
 borne in mind, that the results may be much modified by the 
 quantity employed. In some instances, a very slight excess of 
 reagent may entirely prevent the formation of a precipitate which 
 would otherwise take place. Thus a solution of morphine, when 
 treated with a given quantity of caustic potash, may yield a 
 copious crystalline deposit, while with sKght excess of the re- 
 agent, it may yield no precipitate whatever. On the other hand, 
 a deficiency of reagent may produce results very different from 
 those occasioned by other quantities. A limited quantity of 
 sulphuretted hydrogen throws down from a solution of corrosive 
 subhmate a white precipitate; while excess of the reagent pro- 
 duces a Hack deposit. Any quantity of reagent above that 
 necessary to produce the desired result, is an excess and may 
 do harm, if only by diluting the mixture. 
 
 AU apparatus employed in contact with the suspected sub- 
 stance under examination, should either be of glass or of weE- 
 glazed porcelain, and be washed with scrupulous care. In fine, 
 any article about to be thus employed, whose purity is not en- 
 tirely above suspicion, should be rejected. 
 
 Qualifications of the analyst. — A chemico-legal investigation 
 of this nature, as well remarked by Prof. Otto in regard to the 
 
QUALIFICATIONS OF THE ANALYST. 61 
 
 detection of arsenic, should be intrusted only to an experienced 
 chemist. He should not only be acquainted with the principles 
 involved in the analysis, but know from experience how to per- 
 form it in all its details, and be able to defend his conclusions 
 from any objections that might arise at a subsequent trial. If 
 he be unacquainted with the details of the analysis of the special 
 poison uader consideration, he should familiarise himself with 
 them by repeated experiments upon known and minute quantities 
 'of the substance suspected to be present, under conditions similar 
 to those under which it is supposed to exist. To point out the 
 methods by which the presence of any of the poisons therein 
 considered may be fully established, and give directions whereby 
 those having only a limited knowledge of practical chemistry 
 may acquaint themselves with the details of the analysis, are 
 among the objects of the following pages. 
 
 In the special consideration of the different poisons, they 
 win be grouped together, in accordance with their chemical rela- 
 tions or for convenience, rather than in regard to their physio- 
 logical effects. They wiU be discussed imder two general Parts 
 of the work: Part First will contain the inorganic poisons, with 
 which will be included Hydrocyanic and Oxalic acids; Part 
 Second will be confined to the consideration of vegetable poisons. 
 
PAET FIEST. 
 
 INORGAlSriC POISOl^^S. 
 
INORGANIC POISONS. 
 
 OHA^TEE I. 
 
 THE ALKALIES: POTASH, SODA, AMMONIA. 
 
 General Chemical Nature. — In their general chemical 
 nature the alkalies, potash, soda and ammonia, and their salts, 
 form a quite natural and distinct group of compounds.* When 
 in solution, either in their uncomhined state or as protocarbon- 
 ates, they have a strong alkaKne reaction, immediately restoring 
 the blue color of reddened litmus-paper. They differ from most 
 other metaUic oxides in being freely soluble in water; the same 
 is also true in regard to many of their salts, especially their sul- 
 phurets and carbonates. From their aqueous solutions, they are 
 not precipitated under any condition by either sulphuretted hy- 
 drogen, sulphuret of ammonium or carbonate of soda; whereas all 
 other metals are precipitated by one or more of these reagents. 
 This difference of behavior is due to the fact that the sulphurets 
 and carbonates of the alkahes are freely soluble, whilst the cor- 
 responding salts of aU other metals are iasoluble in water. Nor 
 do the alkalies precipitate each other when in solution in their 
 free state; and the same is true, with very few exceptions, in 
 regard to their salts. As potash and soda, and their salts, unlike 
 ammonia and its salts, are not dissipated upon the application 
 of heat, they are called fixed alkalies. 
 
 Physiological Effects. — Although the alkahes and many of 
 their salts are highly poisonous, yet they have very rarely been 
 
 * In the present consideration of the distinguishing properties of the above- 
 named alkalies, the properties of the very rare suhstanoe lithia, as well as those 
 of the two recently-discovered and exceedingly rare alkalies, cassia and rubidia, 
 will be entirely omitted. 
 
 5 
 
66 THE ALKALIES. 
 
 administered criminally or taken for the purpose of suicide. 
 They have, however, not unfrequently been taken by accident 
 and produced fatal results. As the effects of the different alka- 
 Kes upon the animal economy are very similar in their nature, 
 they Moll in this respect be considered together; but treated of 
 separately when considering their chemical properties. 
 
 Symptoms. 1. Of the fixed Alkalies. — When a strong solu- 
 tion of either of these compounds or of their carbonates, is 
 taken iato the mouth, the individual immediately experiences a 
 nauseous acrid taste, and there is rapid disorganisation of the 
 mucous membrane of the parts with which it comes in contact. 
 On account of the immediate and exceedingly acrid taste of 
 these substances, the solution is sometimes rejected from the 
 mouth without any portion of it being swallowed. If the solu- 
 tion be swallowed, it gives rise to a sense of burning heat and 
 constriction in the fauces, oesophagus and stomach, followed by 
 violent vomiting of mucus matters, which sometimes contain 
 blood. These symptoms are generally followed by intense pain 
 in the stomach, tenderness of the abdomen, bloody purging, 
 great muscular prostration, and sometimes convulsions. The 
 pulse becomes rapid, small and thready; the skin covered with 
 cold perspiration; and the mouth, tongue and throat, inflamed 
 and swollen. If the patient survive a few days, there may be 
 sloughing of the fauces, which may end in stricture of the 
 oesophagus, and thus death finally take place from starvation. 
 Death has in some instances resulted from inflammation and 
 obstruction of the air-passages. 
 
 2. Of Ammonia. — The effects produced by stroiig solutions of 
 ammonia, as aqua ammonice, axe much the same as those of the 
 fixed alkahes and their carbonates; but, in some instances, it is 
 even more severe in its action. With very few exceptions, 
 instances of poisoning by this substance have been the result of 
 accident; and in some of these death took place with great 
 rapidity. In a case of poisoning by a solution of this kind 
 taken with suicidal intent, quoted by Dr. StiU^, the symptoms 
 were collapse, serous and bloody purging, bloody vomiting, ex- 
 cruciating pain in the abdomen, and death in six hours. If the 
 patient . survive the primary effects of this poison, he is less 
 
PHYSIOLOGICAL EFFECTS. 67 
 
 likely to die from secondary effects than in poisoning by the 
 fixed alkalies. 
 
 The vapor of ammonia, even when largely diluted with 
 atmospheric air and inhaled, produces violent dyspnoea, severe 
 pain in the throat, irritation and inflammation of the air-pas- 
 sages and lungs, and in some instances death. In the related 
 case of a druggist, who accidentally inhaled the fumes of am- 
 monia from a broken carboy, there was corrosion of the mucous 
 membrane of the mouth and nostrils, great difficulty of breath- 
 ing, feeble and irregular pulse, and a bloody discharge from the 
 mouth and nose. These effects were followed by a most violent 
 attack of bronchitis, during which the patient could not speak 
 for several days; but he ultimately recovered. The injudicious 
 use of this vapor for the purpose of rousing persons from a state 
 of insensibihty, has in several instances been followed by fatal 
 results. 
 
 The carbonates of ammonia, of which there are several, are 
 less intense in their action than a solution of the free alkali, 
 their intensity diminishing in proportion to the increase of car- 
 bonic acid. 
 
 Period when fatal. — In poisoning by either of the above 
 substances, death may take place within a short period from the 
 immediate effects of the poison; or the patient may recover 
 from the primary irritation and ultimately die from secondary 
 results months or even years after the substance had been taken. 
 In a case described by Mr. Dewar, a Httle boy who swallowed 
 by mistake about three ounces of a strong solution of carbonate 
 of potash, died from its effects in twelve hours afterwards. 
 (Edin. Med. and Surg. Jour., xxx, 309.) In another instance, 
 related by Dr. Cox, a small quantity of deliquesced carbonate 
 of potash, proved fatal in twenty-four hours, to a child aged 
 three years. 
 
 On the other hand, two sisters, aged respectively twelve and 
 sixteen years, took by mistake about half an ounce of subcar- 
 bonate of potash each. Violent symptoms immediately ensued, 
 and in the case of the elder continued with little interruption for 
 about two months, when death took place. In the case of the 
 other, the symptoms abated after a few days; but they again 
 
68 THE ALKALIES. 
 
 returned, and finally proved fatal after the lapse of nearly three 
 months. (Beck's Med. Jur., ii, p. 524.) In a case recently 
 reported by Dr. Deutsch, a solution estimated to contain about 
 half an oimce of caustic potash, did not prove fatal until after a 
 period of twenty-eight weeks. And in another, a quantity of 
 impure carbonate of soda produced stricture of the gullet, of 
 which the patient died two years and three' months after having 
 taken the poison. Sir C. Bell even relates a case of this kind, 
 in which death did not take place mitil after the lapse of twenty 
 years. 
 
 Solutions of ammonia have proved rapidly fatal. In a case 
 related by Plenck, a quantity of liquor ammonia poured into the 
 mouth of a man who had been bitten by a mad dog, caused 
 death in four minutes. (Christison on Poisons, p. 194.) A case 
 in which a solution of this kind proved fatal in six hours, has 
 already been cited. Dr. Taylor records the case of a gentleman 
 who died in three days, from the eifects of a solution of ammonia 
 administered to him by mistake. (On Poisons, p. 331.) The 
 vapor of ammonia applied to the nostrils of a lad laboring under 
 a fit of epilepsy, induced bronchitis which proved fatal in forty- 
 eight hours. In a somewhat similar case, death ensued on the 
 third day. 
 
 Fatal quantity. — It is impossible at present to state with any 
 degree of certainty the smallest quantity of either of the sub- 
 stances under consideration that might prove fatal. In most 
 instances the effects wiU. depend rather upon the degree of con- 
 centration imder which the substance is taken, than the absolute 
 quantity. In an instance recorded by Dr. Taylor (Op. cit., p. 
 328), one ounce and a half of the common solution of potash of 
 the shops, proved fatal to an adult, in seven weeks. The quan- 
 tity of the caustic alkali taken in this case, did not perhaps 
 exceed forty grains, which is the smallest fatal dose we find 
 recorded. There are not less than four cases reported, two of 
 which have already been cited, in which half an ounce of the 
 carbonate of potash proved fatal : in all of these, as in the pre- 
 ceding case, death was due to the secondary effects of the poison. 
 
 Solutions of ammonia have also proved fatal when taken 'in 
 small quantity. Thus this event has happened in at least two 
 
POST-MORTEM APPEARANCES. 69 
 
 instances, in which not over two drachms had been taken. 
 Instances of recovery from this substance, however, have been 
 of more frequent occurrence than from the fixed alkalies. A 
 man swallowed by mistake, three drachms of a strong solution 
 of ammonia and as much of the sesquicarbonate, dissolved in 
 two ounces of oil ; but under appropriate, treatment he recovered 
 in about eight days. (Wharton and StiQe's Med. Jur., p. 502.) 
 In another case, a boy aged two years, took half an ounce of 
 very pungent spirits of hartshorn, and recovered. Instances are 
 also related in which recovery took place, even after more than 
 an ounce of the solution had been taken. 
 
 Treatment. — The antidote for poisoning by any of the free 
 alkalies or their carbonates, is the speedy administration of a 
 solution of some of the mild vegetable acids — such as acetic 
 acid in the form of dUuted vinegar, or the juice of any of the 
 acid fruits — ^by which the poison will to a certain extent be 
 neutraKsed. Large quantities of olive oil have in some in- 
 stances been administered with advantage. This substance may 
 convert the alkali into a soap, and thus prevent its caustic action. 
 Large draughts of milk may also be used with benefit. In pois- 
 oning by the vapor of ammonia, Dr. Pereira recommends the 
 inhalation of the vapor of acetic or of dilute hydrochloric acid. 
 
 PoST-MOETEM APPEARANCES. — These will depend in a great 
 measure upon the length of time the patient survived the taking 
 of the poison. In acute cases, the mucous membrane of the 
 parts with which the substance comes in contact is more or less 
 disorganised, beiag inflamed and broken up in patches ; some- 
 times there is extravasation of disorganised blood upon the walls 
 of the organs thus aff'ected, which causes them to present a blu- 
 ish, or black appearance. This appearance is sometimes wefl 
 marked in the mouth. In some instances, large portions of the 
 mucous membrane of the mouth, oesophagus and stomach, are 
 entirely removed. 
 
 In Mr. Dewar's case, in which death was produced in twelve 
 hours by a solution of carbonate of potash, the appearances were 
 much the same as those just described. Thus, the mucous 
 membrane of the pharynx and cesophagus was almost entirely 
 destroyed, and dark blood extravasated beneath the pulpy mass ; 
 
70 THE ALKALIES. 
 
 in the stomach, the mucous membrane was destroyed in two 
 places, and these patches covered with clotted blood. Similar 
 appearances were found in the case that proved fatal in twenty- 
 four hours. 
 
 In the case of poisoning by ammonia quoted above, which 
 proved fatal in three days, the Kning membrane of the trachea 
 and bronchi was softened and covered with layers of false mem- 
 brane ; while the larger bronchial tubes were completely ob- 
 structed by casts of this membrane. The mucous membrane of 
 the gullet was softened, and the lower end of the tube completely 
 destroyed. The anterior wall of the stomach contained an aper- 
 ture about an inch and a half in diameter, through which the 
 contents of the organ had escaped. 
 
 In chronic cases, the lower portion of the oesophagus and 
 the stomach are frequently much contracted. The walls of the 
 stomach are often thickened, and the lining membrane wholly 
 destroyed. An ulcerated and gangrenous state of the mucous 
 membrane of the stomach and intestines, has also been observed. 
 And in some instances, other of the abdominal organs have been 
 much disorganised. In Dr. Deutsch's case, the mucous mem- 
 brane of the lower portion of the oesophagus was found so 
 greatly thickened, that the opening into the stomach was nearly 
 obhterated. 
 
 Nitrate of Potash. — This salt, commonly known by the 
 name of saltpetre or nitre, has in several instances been taken 
 by accident, with fatal results. To produce serious effects, how- 
 ever, it requires to be taken in large quantity, such as half an 
 ounce or more. The symptoms usually observed are severe 
 burning paia in the stomach and abdomen, nausea, vomiting and 
 purging, followed by coldness of the extremities, tremors and 
 coUapse. The effects of large doses have, however, been subject 
 to considerable variation. 
 
 In a case recorded by Dr. Beck, a dose of this salt taken in 
 mistake for Grlauber's salt, proved fatal to an aged man, in half 
 an hour; and in an instance cited by Orfila, one ounce caused 
 death in three hours. A man, who took three ounces and a 
 half of the salt at a dose, apparently siiffered but Kttle for five 
 
CHEMICAL PROPERTIES. 71 
 
 hours, when he suddenly fell out of his chair and expired. Re- 
 covery has in several instances taken place, even after so much 
 as two ounces of the salt had been taken. 
 
 The treatment consists in the speedy removal of the poison 
 from the stomach, and the subsequent exhibition of demulcents. 
 No chemical antidote is known. 
 
 After death, the stomach has been found highly inflamed, 
 mottled with dark-colored patches, and the mucous membrane 
 partially detached. Similar appearances have also been observed 
 in the small intestines. In at least one instance, the coats of 
 the stomach were perforated by a small opening. 
 
 The Tartrate, Sulphate and Binoxalate of Potash have 
 also destroyed life. The noxious effects of the last-mentioned 
 salt, however, chiefly depend upon the oxalic acid which it 
 contains. 
 
 Chemical Properties of the Alkalies. 
 
 Distinguishing properties. — Solutions of the caustic aUtahes, 
 are distinguished from those of their carbonates, by the latter 
 effervescing, from the escape of carbonic acid gas, when acted 
 upon by hydrochloric dr any of the strong acids. Sulphate of 
 MAGNESIA, at ordinary temperatures, throws down from solutions 
 of th.Q protocQ,rl)onates of ^q fixed alkalies a white precipitate; 
 whereas with the hicarhonates, it produces no precipitate. This 
 reagent fails to precipitate solutions of either of the carbonates 
 of ammonia. 
 
 Nitrate of Silver produces in solutions of the fixed caustic 
 alkaUes, a brown precipitate, which is insoluble in excess of the 
 alkah; while in a solution of ammonia, it produces a somewhat 
 similar precipitate, readily soluble in excess of the alkah : when, 
 therefore, the reagent is not added in excess, the ammoniacal 
 solution fails to yield a precipitate. Solutions of the carbonates 
 of either of the alkaKes, yield with this reagent a yellowish- 
 white precipitate, which in the case of the fixed alkalies is itisol- 
 uble in excess of the alkaline salt, while that from either of 
 the carbonates of ammonia is soluble in excess of the alkaline 
 compound. The precipitation of the bicarbonates by this reagent. 
 
72 POTASH. ^ 
 
 is attended with effervescence, due to the escape of carbonic 
 acid, but this result is not observed in the case of the protocar- 
 bonates. 
 
 Corrosive Sublimate throws down from solutions of the 
 fixed alkalies, a bright yellow precipitate, which is insoluble in 
 excess of the alkali ; from the protocarbonates a reddish-brown ; 
 but in solutions of the bicarbonates it produces no precipitate. 
 With ammonia and its carbonates, this reagent produces a white 
 precipitate, which is somewhat soluble in excess of the alkaline 
 solution, especially in the presence of ammoniacal salts. 
 
 The different alkalies will now be separately considered, in 
 regard to their chemical nature and reactions, and the methods 
 by which they may be recovered from organic mixtures. 
 
 Section I. — Potash. 
 
 General Chemical Nature. — Potash is a compound of the 
 elements potassium and oxygen (KO) ; in combination with one 
 equivalent of water, it forms the hydrate of potash (KO, HO) ; 
 known also by the names potassa fusa and caustic potash. This 
 compound, when pure, is a white solid, but as usually met with 
 in the shops in the form of little sticks, it has a greyish or 
 brownish color, due to the presence of foreign matter. When 
 exposed to the air, it deliquesces and slowly absorbs carbonic 
 acid, becoming changed into the carbonate of potash. 
 
 Caustic potash dissolves, with the evolution of heat, in about 
 half its weight of water; it is about equally soluble in alcohol. 
 Its solubility in alcohol enables us to separate it from many of 
 its salts, such as the proto- and bi-carbonates, nitrate and sul- 
 phate, which are insoluble in this liquid. An aqueous solution 
 of caustic potash changes an infusion of violets or of red cab- 
 bage to green, an infusion of tumeric to reddish-brown, and 
 immediately restores the blue color of reddened litmus, even 
 according to Harting, when the alkali is dissolved in 75,000 
 parts by weight of water. A saturated aqueous solution of pure 
 caustic potash has a density of about 2, and contains about 70 
 per cent, of the anhydrous alkali. 
 
SPECIAL CHEMICAL PROPERTIES. 
 
 73 
 
 The following table, by Dalton, indicates approximately the 
 per cent, of anhydrous potash (KO) in solutions of the alkali of 
 the different given specific gravities : — 
 
 STRENGTH OF AqUEOUS SOLUTIONS OF POTASH. 
 
 SP. GR. 
 
 PER CENT. 
 
 SP. GR. 
 
 PER CENT. 
 
 1.78 
 
 56-8 
 51-2 
 46-7 
 42-9 
 39-6 
 36-8 
 34-4 
 32-4 
 
 1.36 
 
 29-4 
 26-3 
 23-4 
 19-0 
 16-2 
 13-0 
 9-5 
 4-7 
 
 i-es 
 
 1-33 
 
 1-60 
 
 1-28 ; 
 
 1.52 
 
 1-23 
 
 1-47 
 
 1.19 
 
 1.44 
 
 1.16 
 
 1-42 
 
 1.11 
 
 1-39 
 
 1-06 
 
 
 
 Potash, in its action upon animal tissues, is the most de- 
 structive of the alkalies. When rubbed between the fingers, by 
 its chemical action on the skin, it imparts a soapy feel. It 
 forms soluble compounds with many of the constituents of the 
 animal tissues ; and it may dissolve and perforate the coats of 
 the stomach, even more readily than the mineral acids. 
 
 The salts of potash are colorless except those in which the 
 constituent acid is colored ; and they generally crystallise with- 
 out water of crystallisation, in which they differ in most 
 instances from the corresponding salts of soda. With very few 
 exceptions, they are freely soluble in water. 
 
 Special Chemical Properties. — Potassium compounds when 
 heated upon a clean platinum wire, in the reducing blow-pipe 
 flame, impart a violet color to the outer flame. This reaction 
 may be entirely masked by the presence of even a small quan- 
 tity of soda, which gives a strong yellow color to the outer 
 flame. In like manner, an alcoholic solution of potash or of any 
 of its salts, bums with a violet flame ; but this reaction is also 
 obscured by the presence of soda. 
 
 On account of the solubility of most of the compounds of 
 potassium, there are but few reagents that precipitate it from 
 solution, and these only when the solution is comparatively 
 strong. Before applying any liquid test for the detection of 
 potash or either of the alkalies, the absence of metallic oxides 
 
74; POTASH. 
 
 Other than those of the alkalies, should be established. This 
 may be done by treating a small portion of the solution, acidu- 
 lated with hydrochloric acid, with sulphuretted hydrogen; an- 
 other, and neutral portion, with sulphuret of ammonium ; and a 
 third portion, with carbonate of soda : when, if these reagents 
 fail to produce a precipitate, it foUows that the metallic oxides 
 mentioned are absent. 
 
 In applying a liquid reagent, a drop of the suspected solu- 
 tion may be placed in a watch-glass, and a small portion of the 
 reagent added by means of a pipette. The mixture may then 
 be examined by the microscope. If there be no immediate 
 precipitate, it must not be concluded that the base in question 
 is entirely absent ; but the mixture should be allowed to stand, 
 even in some instances for several hours, before deciding the 
 entire absence of the substance. 
 
 In the following examinations of the behavior and limit of 
 the different tests for the alkali under consideration, solutions of 
 the chloride of potassium and of nitrate of potash, were chiefly 
 employed. The fractions indicate the fractional part of a grain 
 of anhydrous potash, under the form of the salt employed, in 
 solution in one grain of pure water; and the results, unless 
 otherwise stated, refer to the behavior of one grain of the solu- 
 tion, treated in the manner described above. 
 
 1. Bichloride of Platinum. 
 
 Bichloride of platinum throws down from solutions of salts 
 of potash, when not too dilute, a yellow precipitate of the 
 double chloride of platinum and potassium (KCl, PtCy, which, 
 either immediately or after a very little time, becomes converted 
 into beautiful octahedral crystals. Solutions of the free alkali 
 should be treated with slight excess of hydrochloric acid, before 
 the addition of the reagent. From dilute solutions, the presence 
 of a little free hydrochloric acid, or of strong alcohol, facilitates 
 the formation of the precipitate. 
 
 The precipitate is soluble in about one hundred and eight 
 parts by weight of pure water at the ordinary temperature, but 
 it is much more freely soluble in hot water; it is somewhat less 
 
SPECIAL CHEMICAL PROPERTIES. 75 
 
 soluble in water containing a trace of hydrochloric acid, and 
 almost wholly insoluble in absolute alcohol. One part by weight 
 of anhydrous potash or its equivalent in the form of a salt, 
 yields 5-2 parts of the double salt. 
 
 1. sV grain of potash in the form of chloride of potassium, in 
 
 solution in one grain of water, yields with the reagent an 
 immediate yellow crystalline precipitate, which very soon 
 increases to a copious deposit. On stirring the mixture 
 with a glass rod, it leaves Knes of crystals where the rod 
 has passed over the watch-glass. 
 
 The same amount of potash in the form of nitrate, 
 yields about the same results. 
 
 2. Y^ grain as chloride : crystals are immediately perceptible, 
 
 and soon there is a fine crystalline deposit, which mader 
 the microscope presents the appearance represented in 
 Plate I, fig. 1. When the potash is in the form of nitrate, 
 the precipitate is a little more slow in forming, and does 
 not become quite so abundant. 
 
 3. ■2s"cr grain: in about two minutes there is a perceptible pre- 
 
 cipitate, and after a little time a quite good crystalline 
 deposit. If the mixture be stirred, it yields streaks of 
 granules. From the nitrate of potash, the precipitate is 
 more slow to form and does not become so abundant, the 
 crystals being confined to the border of the mixture. A 
 200th solution of the nitrate yields only about the same 
 results as a 250th solution of the chloride. 
 
 4. Too" grain : in about ten minutes crystals appear around the 
 
 margin of the mixture ; these increase, and in about three- 
 quarters of an hour, there is quite satisfactory deposit scat- 
 tered through the body of the drop. Stirring the mixture 
 does not seem to facilitate the formation of the deposit. The 
 forms of the crystals are much the same as illustrated above. 
 A 400th solution of the nitrate yields only about the 
 same reaction as a 500th solution of the chloride. A 500th 
 solution of the nitrate, however, will yield a perceptible 
 deposit after standing about an hour. In these experi- 
 ments, concentration of the mixture from evaporation, was 
 guarded against, perhaps, however, not perfectly. 
 
76 POTASH. 
 
 Harting placed the limit of this test, when applied to a solu- 
 tion of the nitrate, at one part of anhydrous potash in 205 
 parts of water (Gmelin's Handbook, iii, p. 15). Lassaigne 
 fixed the lindt for sulphate of potash, at one part of the alkali 
 in 200 parts of water (Jour. Chim. Med. 8, 527). And for the 
 acetate, Pettenkofer placed the limit at one part of potash in 
 500 parts of water, after standing from twelve to eighteen hours ; 
 but, he states, when common salt is present, the reaction is lim- 
 ited to one part of the alkali in 100 parts of water, or even less 
 (G-mehn, x, 276). Neither of these observers, however, state 
 the quantity of solution employed in the experiment. 
 
 Fallacy. — Bichloride of platinum also produces a similar yel- 
 low crystalline precipitate in solutions of salts of ammonia. The 
 absence of these salts should, therefore, be established before 
 concluding that the precipitate consists of the potassium com- 
 pound. This may be done, by adding some hydrate of lime or 
 caustic potash to a small portion of the suspected solution and 
 heating the mixture, when if it contain an ammoniacal salt, the 
 odor of this alkali wiU be evolved. Or, the precipitate produced 
 by the platinum reagent, may be heated to redness, when the 
 potassium compound wiU leave a residue of chloride of potassium 
 and metallic platinum, which when treated with a small quan- 
 tity of hot water and the filtered Hquid acted upon by a solution 
 of nitrate of silver, will yield a white precipitate of chloride of 
 silver, due to the presence of the alkaKne chloride ; whereas, 
 the ammonium compound wiU leave upon ignition a residue of 
 only metallic platunun, which, of course, wiU yield no precipi- 
 tate with nitrate of silver. 
 
 2. Tartaric Acid, and Tartraie of Soda. 
 
 Tartaric acid, when added in excess to somewhat strong solu- 
 tions of potash and. of its salts, produces a white crystalline 
 precipitate of tartrate of potash (KO, HO, C8H4O10). From 
 somewhat dilute solutions, the precipitate is slow in appearing ; 
 in such cases, its formation is much facilitated by agitation, as 
 also by the addition of alcohol. The precipitate is soluble in 
 the mineral acids, and free alkalies and their carbonates | if 
 
SPECIAL CHEMICAL PROPERTIES. 77 
 
 therefore, either of these substances be present in excess, the 
 formation of the precipitate will be entirely prevented. The 
 precipitate is insoluble in free tartaric and acetic acids. 
 
 When a solution of a salt of potash is treated with free tar- 
 taric acid, it is obvious that the acid of the salt is set free, 
 thus: KO,N05+2HO; CsH40io* = KO, HO, CsHAo+HO, NO5. 
 The acid thus set free, may in a measure redissolve the tar- 
 trate of potash produced by the reagent, especially if it be one 
 of the stronger acids. This elimination of the acid may be 
 prevented by using the reagent in the form of a solution of the 
 acid tartrate of soda, as first recommended by Mr. Plunkett 
 (Chem. Gaz., xvi, 217). Under these conditions, there would 
 simply be an interchange of acids and bases, the soda elimi- 
 nated from the tartaric acid combining with the acid set free 
 from the potash. This reagent is readily prepared by dividing 
 a strong solution of tartaric acid into two equal parts, exactly 
 neutralising one of them with pure carbonate of soda, and then 
 adding the other. 
 
 In the following investigations, a very strong solution of 
 free tartaric acid, and a saturated solution of the acid tartrate 
 of soda, were employed as the reagents. 
 
 1. sV grain of potash in the form of chloride or nitrate, yields 
 
 with free tartaric acid, an immediate crystalline precipi- 
 tate, which soon increases to a very good deposit. The 
 tartrate of soda produces much the same results, except 
 perhaps, the precipitate is somewhat more copious; the 
 general forms of the crystals, however, are quite different. 
 The neutral tartrate of soda produces no precipitate. 
 
 2. Too grain: crystals immediately begin to separate, and after 
 
 a little time there is a good crystalline deposit. Plate I, 
 fig. 2, represents the usual forms of the crystals produced 
 
 *The sign of the semicolon (;) when employed in chemical formula throughout 
 the present work, will imply that the multiplication of the figure preceding the 
 expression, ceases at that point. Thus, the above expression (2 HO ; CsHiOjo), 
 implies one chemical equivalent of a compound, consisting of two equivalents of 
 water (HO) with one equivalent of anhydrous tartaric acid (GiS.iO\f)). On the 
 other hand, when it is desired to not stop such multiplication, and at the same 
 time indicate that two or more compounds are in intimate union, the sign of the 
 comma (,) will be employed. 
 
1 
 
 25 ( 
 
 78 POTASH. 
 
 by free tartaric acid. Tartrate of soda produces a some- 
 what more abundant precipitate. 
 
 j-g- grain: in a few moments crystals appear, and very soon 
 there is a quite satisfactory deposit. With the tartrate of 
 soda and chloride of potassium, the precipitate is some- 
 what more prompt in appearing. Plate I, fig. 3, repre- 
 sents the forms of crystals usually produced by the soda 
 reagent. 
 
 4. 5-00- grain as chloride: within a few minutes granules ap- 
 
 pear ; these soon become crystalline, and after a little time 
 there is a quite satisfactory crystalline and granular de- 
 posit. From the nitrate of potash, the precipitate sepa- 
 rates much more slowly, and is chiefly confined to the 
 border of the mixture; under the microscope, however, 
 the reaction is quite satisfactory. After standing about 
 half an hour, either of these solutions yields a quite good 
 deposit of crystals having the forms illustrated above. 
 When tartrate of soda is employed as the reagent, the 
 precipitate is much more prompt in appearing, particu- 
 larly from a solution of chloride of potassium. 
 
 5. ri^ grain as chloride: after about ten minutes, small gran- 
 
 ules form along the margin of the mixture, and after some 
 minutes more, there is a quite distinct granular and crys- 
 talline deposit. With the soda reagent, granules and 
 crystals appear within about four minutes, and there is 
 soon a very satisfactory deposit. 
 
 6. Trroo grain of the chloride, with tartrate of soda: in about 
 
 five minutes, crystals are just perceptible ; and in about 
 
 ten minutes, the deposit is quite distinct, but confined to 
 
 the border of the drop. The crystals have the forms 
 
 illustrated above, some of them being quite large. 
 
 From the above statements it is obvious, that the chloride 
 
 of potassium is the most favorable form of the alkali for the 
 
 application of either of the above reagents. Pettenkofer placed 
 
 the limit of the reaction of free tartaric acid, for solutions of 
 
 the acetate of potash, at one part of the anhydrous alkali in 
 
 from 700 to 800 parts of water, after standing from twelve to 
 
 eighteen hours. 
 
SPECIAL CHEMICAL PROPERTIES. 79 
 
 Fallacy. — These reagents also produce similar crystalline 
 precipitates from solutions of ammonia. The absence of this 
 alkali may be established in the manner indicated under the 
 preceding test. 
 
 3. Oarbazotic Acid. 
 
 A strong alcoholic solution of Garbazotic or Picric acid, 
 when added in excess to solutions of potash and of its salts, 
 produces a yellow precipitate of carbazotate of potash (KO, 
 C12N3H2O13), which is insoluble in excess of the precipitant and 
 in alcohol. The precipitate contains 17'66 per cent, of anhy- 
 drous potash. 
 
 1. sV grain of potash in the form of chloride or nitrate, yields 
 
 an immediate amorphous precipitate, which in a few mo- 
 ments becomes converted into a mass of long regular 
 yellow crystalline needles, some of which extend entirely 
 across the drop of liquid. 
 
 2. xh~o grain: crystals immediately begin to form, and in a very 
 
 little time the drop becomes a mass of very long slender 
 yellow needles, Plate I, fig. 4. 
 
 3. T5^ grain: in a few moments, crystals begin to form, and 
 
 after a little time, a very good deposit of long needles. 
 
 4. TW grain: much the same results as in 3. From the nitrate 
 
 of potash, the precipitate is not so prompt to form, nor is 
 it as abundant as in the case of the chloride. 
 5- Ti~o grain in the form of chloride, yields after a little time a 
 
 perfectly satisfactory crystalline deposit. 
 6. 1,000 grain: after a few minutes, crystalline needles appear 
 along the margin of the drop; after about fifteen minutes, 
 the deposit becomes quite satisfactory, especially when 
 examined by the microscope. 
 In applying this reagent it should be added in large excess. 
 Thus, ten grains of a 500th solution of the alkaline salt, when 
 acted upon by a drop or two of the reagent yield no precipitate, 
 at least for some time; but if an equal volume of the reagent 
 be added, it produces a precipitate within a few moments. 
 
 Fallacies. — Carbazotic acid also throws down from solutions 
 of ammonia and very strong solutions of soda, yellow crystal- 
 
80 POTASH. 
 
 line precipitates. The microscope, however, will readily enable 
 us to distinguish the potash precipitate by its crystalline form, 
 from that of either of these substances. (Compare figs. 5 and 
 6, Plate I.) The reagent also produces yellow precipitates, 
 some of which are crystalline, with many organic substances, 
 especially the vegetable alkaloids. So also, it occasions precip- 
 itates with certain other metallic oxides ; but the absence of 
 these, as already pointed out, should be established before ap- 
 plying the test. 
 
 In applying this test it must be remembered, that a very 
 strong alcoholic solution of the reagent when added in certain 
 proportion to pure water, may yield a yellow crystalline precip- 
 itate of free carbazotic acid. The forms of these crystals, how- 
 ever, readily distinguish them from the potash compound. In 
 a 500th or stronger solution of the alkali, this distinction is 
 very apparent to the naked eye; and in more dilute solutions, 
 it is readUy established by the microscope. 
 
 In addition to the above, there are several other reagents 
 that precipitate potash, only, however, from concentrated solu- 
 tions. 
 
 Hydrofluosilicic acid in excess produces in solutions of 
 the alkali, a transparent gelatinous precipitate of the silicoflu- 
 oride of potassium, which is insoluble in hydrochloric acid. In 
 concentrated solutions this reaction is very satisfactory. A 
 50th solution of the alkali in the form of chloride, yields after 
 a time, only a slight flocculent deposit. 
 
 Perchloric acid produces in similar solutions, a white 
 crystalline precipitate of perchlorate of potash. So also, a 
 concentrated solution of Sulphate of Alumina, when added to 
 concentrated solutions of the alkah previously acidulated with 
 hydrochloric acid, precipitates crystals of the double sulphate 
 of alumina and potash, or common alum. 
 
 Spectrum analysis. — This, as first applied by Professors 
 Kirchoff and Bunsen, is by far the most delicate method yet 
 discovered for the recognition of potassium — as well as of 
 sodium and many other volatile metals. It consists in intro- 
 ducing a small portion of the caustic alkali, or any of its salts 
 
SEPARATION FROM ORGANIC MIXTURES. 81 
 
 containing a volatile acid, into the flame of a Bunsen gas-burner 
 and allowing the rays of the colored flame to pass through a 
 prism. The refracted rays are then examined by means of a 
 small telescope, when, in the case of potassium, two distinct 
 lines, one having a red color and the other indigo-blue, will be 
 observed, which are characteristic of this metal. The authors 
 of this method, estimated that it would reveal the reaction of 
 the 65,000th part of a grain of potassium, and the 195,000,000th 
 part of a grain of sodium. (For the details of this method, see 
 Quart. Jour. Chem. Soc, Oct., 1860; also, Fresenius' Qual. 
 Analysis, London, 1864.) 
 
 Although spectrum analysis has very largely extended the 
 scope of chemical research, enabling us in a few seconds to 
 detect the presence of the most minute traces of many metals, 
 and bringing to light substances of which heretofore we had no 
 knowledge; yet as it gives no indication whatever as to the 
 quantity of the substance present, it is still doubtful whether it 
 will be of any practical value in chemico-legal investigations, 
 at least for the detection of the fixed alkalies, since these are 
 so universally distributed through the tissues and juices of both 
 animal and vegetable structures. 
 
 Separation from Organic Mixtures. 
 
 When the suspected solution is highly colored or contains 
 much organic matter, the tests for either of the alkalies cannot 
 be satisfactorily applied directly to the mixture. If the solu- 
 tion has a soapy feel, a strong alkaline reaction, and is destitute 
 of the odor of ammonia, even when a small portion of it is 
 heated with hydrate of lime, the presence of one or other, or 
 both of the fixed alkalies, or of their carbonates may be inferred. 
 
 Either of the fixed alkalies may be separated from their 
 carbonates and organic matter, by evaporating the mixture on 
 a water-bath to about dryness and digesting the cooled residue 
 with absolute alcohol, which will dissolve the free alkali, while 
 its carbonates, and other salts if present, will remain undis- 
 solved. The alcoholic solution is then concentrated to a small 
 volume, and if strongly alkaline and nearly colorless, at once 
 
82 POTASH. 
 
 neutralised with hydrochloric acid, and examined by the appro- 
 priate reagents. If however, it contains much organic matter, 
 before being tested, it should be evaporated to dryness, the 
 residue incinerated at not above a dull red heat until the 
 organic matter is entirely destroyed, and. the cooled mass dis- 
 solved in water; the aqueous solution is then examined in the 
 ordinary manner. 
 
 Although the alkaline carbonates in their pure state, are 
 almost whoUy insoluble in absolute alcohol, yet the presence of 
 certain kinds of organic matter renders them slightly soluble in 
 this menstruum. A small quantity of these salts may, therefore, 
 be extracted along with the caustic alkali in the above opera- 
 tion. To ascertain the presence of fixed alkaline salts in the 
 residue from which the free alkali was extracted by alcohol, 
 the mass is incinerated in the manner directed above, and the 
 cooled residue dissolved in distilled water. 
 
 Another method recommended for the recovery of the fixed 
 alkalies and their carbonates from complex organic mixtures, 
 is to evaporate the solution to dryness, incinerate the dry mass, 
 and then separate the free alkali from its carbonate by means 
 of absolute alcohol. This method has the advantage of at once 
 destroying the organic matter, but the charring of this converts 
 more or less of the free alkali into carbonate, the quantity thus 
 converted depending upon the relative amount of organic matter 
 present. The amount of free alkali, therefore, furnished by 
 this method would be somewhat less than originally existed; 
 while by the preceding process, the estimate of this substance 
 might be somewhat too high. 
 
 Quantitative Analysis. — The quantity of potash present 
 in pure solutions of the free alkali or of its carbonates, may be 
 estimated by precipitating it in the form of the double chloride 
 of platinum and potassium. For this purpose, the alkali is 
 converted into chloride, by the addition of hydrochloric acid, 
 and the somewhat concentrated solution treated with slight 
 excess of bichloride of platinum. When the precipitate has 
 completely deposited, the mixture is concentrated on a water- 
 bath, to near dryness, and the cooled residue washed with 
 
SODA: GENERAL CHEMICAL NATURE. 
 
 83 
 
 strong alcohol, which will remove the excess of reagent added. 
 The residue, consisting of the double salt, is then collected on 
 a filter of known weight, washed with a little more alcohol, 
 dried, and weighed. Every 100 parts by weight of the double 
 salt thus obtained, represent 22-5 parts of caustic potash 
 (KO, HO) ; or 28-25 parts of anhydrous carbonate of potash 
 (KO, 00^). 
 
 In all investigations of this kind, the original solution pre- 
 sented for examination should be carefully measured, and a 
 given portion set apart for the quantitative analysis. From 
 the amount of poison discovered in this, the entire quantity 
 present, may, of course, be readily deduced. 
 
 Section II. — Soda. 
 
 GrENERAL .Chemical Natuee. — This alkali, in the form of 
 hydrate of soda, or caustic soda (NaO, HO), is a white opake, 
 powerfully alkaline, caustic substance, which when exposed to 
 the air, absorbs water and carbonic acid, becoming converted 
 into carbonate of soda. In its chemical action upon the tissues, 
 it is somewhat less energetic than the potash compound. It is 
 readily soluble in water, with the evolution of heat, yielding a 
 highly caustic liquid. The aqueous solution, according to 
 Tuennermann, contains the following per cent, of anhydrous 
 soda, NaO, according to the diflferent specific gravities of the 
 solution : — 
 
 STRENGTH OF AqUEOUS SOLUTIONS OF SODA. 
 
 8P. GE. 
 
 PER CENT. 
 
 SP. OR. 
 
 PEE CENT. 
 
 1-428 
 
 30-22 
 26-59 
 22-96 
 20-56 
 18-73 
 16-92 
 14-50 
 
 1-194 
 
 12-69 
 10-87 
 8-46 
 6-64 
 4-83 
 2-41 
 1-20 
 
 1-375 . .. 
 
 1-163 
 
 1-327 
 
 1-123 
 
 1-298 
 
 1-094 
 
 1-277 ■ 
 
 1-067 
 
 1-257 
 
 1.033 
 
 1-228 
 
 1-016 
 
 
 
 The salts of soda are colorless, unless containing a colored 
 acid. They are readily soluble in water, and more disposed 
 
84 SODA. 
 
 than the corresponding compounds of potash, to unite with 
 water of crystallisation. The crystallised protocarbonate, as 
 also several other salts, contains ten equivalents of water of 
 crystallisation. Many of its salts speedily effloresce when ex- 
 posed to the air. 
 
 Special Chemical Pkopekties. — When caustic soda, or 
 any of its salts, is heated in the inner blow-pipe ilame, it com- 
 municates a strong yellow color to the outer flame, even when 
 only a minute quantity of the alkali is present. The presence 
 of potash, even in large quantity, does not obscure this reac- 
 tion. The same coloration is developed when an alcoholic solu- 
 tion of the alkali is burned. By spectrum analysis, as already 
 indicated, the reaction of the merest traces of soda may be 
 recognised. 
 
 On account of the free solubility of the compounds of soda, 
 there are but few reagents that precipitate it even from con- 
 centrated solutions. In fact — besides the coloration of flame — 
 antimoniate of potash and Polarised Light are about the only 
 tests at present known, whereby small quantities of this alkali 
 can be recognised. 
 
 In the following investigations, solutions of pure caustic 
 soda were employed. The fractions refer to the fractional part 
 of a grain of the anhydrous alkali, NaO, in solution in one grain 
 of water; and the results, to the behavior of one grain of the 
 solution. 
 
 1. Antimoniate of Potash. ! 
 
 A solution of this reagent is prepared by supersAtujating 
 warm water with the pure salt, and filtering the liquid when 
 perfectly cold. The solution should always be freshly prepared 
 when required for use. 
 
 Antimoniate of potash throws down from somewhat concen- 
 trated solutions of soda and of its neutral salts, a white crystal- 
 line precipitate of antimoniate of soda (NaO, SbOj). ' The forms 
 of the crystals produced, depend very much upon the strength 
 of the solution. If the solution has an acid reaction, it should 
 be carefully neutralised with potash before the addition of the 
 reagent, since otherwise, free antimonic acid, or biantimoniate 
 
SPECIAL CHEMICAL PROPERTIES. 85 
 
 of potash may be precipitated. The reaction of the reagent is 
 not prevented by the presence of moderate quantities of sahs 
 of potash, excepting the carbonate, in which the soda com- 
 pound is more readily soluble than in pure water. 
 
 1. 2V grain of soda, in one grain of water, yields with the 
 
 reagent an immediate deposit of small granules and rect- 
 angular plates; at the same time, irregular, and tooth- 
 shaped crystals, as represented in the upper left portion 
 of Plate II, fig. 1, float upon the surface of the mixture. 
 
 2. xo grain yields an immediate crystalline precipitate, con- 
 
 sisting principally of small elongated rectangular plates, 
 as represented in the lower portion of Plate II, fig. 1. 
 
 3. YS~o grain : an immediate deposit consisting chiefly of small 
 
 octahedral crystals, as illustrated in the right-hand por- 
 tion of fig. 1, Plate 11. 
 "t- 2^ grain: almost immediately very small granules appear, 
 and soon there is a quite good crystalline deposit of small 
 plates and octahedrons. 
 0- Tffo" grain: after a little time, small crystals can be seen 
 with the microscope; after several minutes, a very satis- 
 factory deposit to the naked eye. If the mixture be 
 stirred with a glass rod, it yields lines of granules along 
 the path of the rod, and a more copious deposit. 
 6. i,Joo grain: on stirring the mixture, crystals become per- 
 ceptible to the microscope, in about five minutes; in about 
 fifteen minutes, they become quite obvious to the naked 
 eye; and after about half an hour, there is a perfectly 
 satisfactory crystalline deposit. 
 Antimoniate of potash fails to precipitate potash and am- 
 monia, even from concentrated solutions; but it produces pre- 
 cipitates in solutions of many other metals : the absence of 
 these, therefore, must be established before concluding that the 
 precipitate consists of the soda compound. 
 
 2. Polarised Light. 
 
 This test, which was first suggested by Prof. Andrews 
 (Chemical Graz., x, 378), is founded upon the fact that the 
 
86 SODA. 
 
 bichloride of platinum, and also the double chloride of potas- 
 sium and platinum, when placed in the dark field of the 
 polariscope, have no depolarising action, whereas the double 
 chloride of sodium and platinum, possesses this property in a 
 remarkable degree. 
 
 To apply this test, its author recommended the following 
 method: Having removed other bases by the ordinary methods 
 and converted the alkalies into chlorides, a drop of the solu- 
 tion is placed on a glass slide and a very small quantity of a 
 dilute solution of the bichloride of platinum added, avoiding as 
 far as possible an excess. This mixture is evaporated by a 
 gentle heat till it begins to crystallise, then placed in the field 
 of a microscope furnished with a good polarising apparatus. 
 On turning the analyser till the field becomes perfectly dark, 
 and carefully excluding the entrance of light laterally, the 
 crystals remain invisible if only the potash compound or the 
 reagent alone, be present, while the presence of the slightest 
 trace of soda is at once indicated by the beautiful display of 
 color of its platinum double salt. Prof. Andrews states that in 
 this manner he obtained a distinct reaction from a quantity of 
 chloride of sodium representing only about the 825,00Gth part 
 of a grain of the anhydrous alkali. 
 
 In applying this method, instead of evaporating the mixture 
 by the application of heat, it is best to allow it to evaporate 
 spontaneously, as it thus yields much larger crystals of the 
 double soda salt. 
 
 1- 1,0 grain of soda in the form of chloride, in one grain of 
 water, when treated with a very small quantity of the 
 reagent and allowed to evaporate spontaneously, leaves 
 a good deposit of long, irregular crystals of the double 
 compound, Plate II, fig. 3. This deposit under the 
 polariscope, furnishes a be'autiful display of prismatic 
 colors. 
 
 2. 10,00 0- grain: quite a number of fine crystals, which in the 
 
 field of the polariscope yield very satisfactory results. 
 
 3. rooToTTo grain, usually yields several quite distinct and sat- 
 
 isfactory crystals. Sometimes the deposit is in the form 
 of thread-like groups, which when broken up. by the point 
 
SPECIAL CHEMICAL PROPERTIES. 87 
 
 of a needle, form small crystalline plates. In this manner, 
 these thread-like masses, may readily be distinguished 
 from depolarising shreds of dust, which are sometimes 
 present. 
 
 4. 5 0^000 grain: with the least possible quantity of reagent, 
 yields a few small depolarising crystalline plates. Even 
 the 1,000,000th part of a grain of the alkali, will some- 
 times yield qtiite distinct results. 
 Before applying this test, the examiner should be certain 
 
 that any potash present is entirely converted into chloride, 
 
 otherwise he may be led into error. 
 
 Carbazotic Acid. — It is usually stated by writers on this 
 subject, that this reagent produces no precipitate even in con- 
 centrated solutions of soda, whereby this alkali is distinguished 
 from potash; but this is not the fact. Thus, one grain of a 
 25th solution of the former alkali, yields with the reagent, 
 within a little time, a quite copious crystalline deposit, Plate I, 
 fig. 6; and a similar quantity of a 100th solution, yields after a 
 time, a quite distinct crystalline reaction. Solutions but little 
 stronger than the first-mentioned, become converted into a mass 
 of crystals by the reagent. 
 
 The crystalline form of the soda precipitate, wiU usually 
 serve to distinguish it from the potash compound, as also from 
 that produced in solutions of ammonia. 
 
 Tartaric Acid produces in very concentrated solutions of the 
 alkali, especially if the mixture be stirred, a white crystalline 
 precipitate of tartrate of soda. In one grain of a 10th solu- 
 tion of the alkali, the reagent produces, on stirring the mixture, 
 after a few minutes, a mass of groups of bold crystals, Plate II, 
 fig. 2. One grain of a 25th solution, under the same circum- 
 stances, yields after ten or fifteen minutes a quite satisfactory 
 crystaUine deposit. If this mixture be not stirred, it fails to 
 yield a precipitate even after several hours. Solutions but 
 little more dilute than this, fail to yield a precipitate under any 
 condition whatever, even after many hours. 
 
 Bichloride of Platinum fails to precipitate even the most 
 concentrated solutions of soda. 
 
88 
 
 AMMONIA. 
 
 Sepaeation from Organic Mixtures. — This may be effected 
 in the same manner as already pointed out for the recovery of 
 potash {ante, p. 81). 
 
 Section III. — Ammonia. 
 
 General Chemical Nature. — Ammonia, in its pure state, 
 is a gaseous compound of Nitrogen and Hydrogen (NH,), hav- 
 ing a very pungent odor and powerfully alkaline reaction. The 
 gas is readily absorbed by water, which is thereby increased 
 in volume and dimiuished in density; at a temperature of 50°, 
 according to Davy, this fluid takes up about 670 times its vol- 
 ume of the gas, and then has a density of 0-875. A solution 
 of this kind constittttes the aqua ammonice of the shops. Ac- 
 cording to Sir H. Davy, the following table exhibits the per 
 cent, by weight, of real ammonia in pure aqueous solutions of 
 diiferent specific gravities: — 
 
 STRENGTH OF AqUEOUS SOLUTIONS OF AMMONIA. 
 
 SP. GK. 
 
 PEE CENT. 
 
 SP. GR. 
 
 PEE CENT. 
 
 0-875 
 
 32-30 
 29-25 
 26-00 
 25-37 
 22-07 
 19-54 
 17-52 
 
 0-938 
 
 15-88 
 14-53 
 13-46 
 12-40 
 11-56 
 10-17 
 9-50 
 
 0-885 
 
 0-943 
 
 0-900 
 
 0-947 . 
 
 0-905 
 
 0-951 .. 
 
 0-916 
 
 0-954 
 
 0-925 
 
 0-959 
 
 0-932 
 
 0-963 
 
 
 
 Aqua ammonice, when pure, is colorless, has a peculiar 
 powerfully pungent odor, and a strong alkaline reaction, imme- 
 diately restoring the blue color of reddened litmus-paper; on 
 warming the blued paper, the red color reappears, from the 
 dissipation of the alkali. On heatiug a solution of ammonia, 
 the gas is rapidly expelled with effervescence; when the liquid 
 is evaporated to dryness it leaves no residue, unless foreign 
 matter be present. 
 
 The salts of ammonia are" colorless, and readily volatilised 
 upon the appKcation of heat. With few exceptions, they are 
 
SPECIAL CHEMICAL PROPERTIES. 89 
 
 freely soluble in water. The fixed caustic alkalies readily 
 decompose them, with the evolution of free ammonia. 
 
 Special Chemical Properties. — Solutions of free ammonia 
 are readily recognised by their peculiar odor. The salts of 
 this base, when heated on platinum foil are completely dissi- 
 pated, unless they contain a fixed acid or foreign matter, in 
 which respect they differ from the salts of the fixed alkalies. 
 When their solutions are treated with caustic potash or soda, 
 or with hydrate of lime, and the mixture gently warmed in a 
 test-tube, the presence of the ammonia eliminated by the de- 
 composition, may be recognised by its odor; as also, by its 
 alkaline reaction upon moistened reddened litmus-paper; and 
 by the production of white fumes of chloride of ammonium, 
 when a glass rod moistened with dilute hydrochloric acid is 
 held over the mouth of the tube. By suspending a slip of 
 moistened reddened litmus-paper within the tube and closing 
 its mouth, the presence of very minute traces of the alkali 
 may, at least after a time, be recognised. 
 
 The behavior of solutions of ammonia and of some of its 
 salts, when treated with nitrate of silver, and corrosive subli- 
 mate, has already been pointed out {ante, p. 71). When the 
 alkali is added in excess to solutions of salts of copper, the 
 liquid assumes a characteristic blue color. 
 
 In the following investigations of the reactions of ammonia, 
 solutions of pure chloride of ammonium were employed. The 
 fractions refer to the amount of pure ammonia present in one 
 grain of the solution, which was the quantity employed for 
 each reaction, unless otherwise stated. 
 
 1. bichloride of Platinum. 
 
 This reagent produces in neutral and slightly acid solutions 
 of ammonia, a yellow octahedral crystalline precipitate of the 
 double chloride of ammonium and platinum (NH^ CI, PtCy, 
 which is but sparingly soluble in diluted mineral acids, and in 
 the free alkalies. In appearance the precipitate closely resem- 
 bles the corresponding compound of potassium. A given quan- 
 tity of ammonia in the form of chloride, yields with the reagent 
 
90 AMMONIA. 
 
 a larger quantity of the double salt, than the same quantity of 
 potash: one part by weight of the former yielding 13'1 parts, 
 and one part of the latter only 5*2 parts of the double compound. 
 !• sV grain of ammonia, in one grain of water, when treated 
 Avith the reagent, the mixture immediately becomes con- 
 verted into an almost solid mass of crystals. The pre- 
 cipitate is much more copious than that from a similar 
 solution of potash, but the crystals are somewhat smaller, 
 and a portion of the deposit is in the form of granules. 
 
 2. Too' grain: in a very few moments a very copious crystal- 
 
 line deposit. 
 
 3. 2^ grain: the precipitate begins to appear within a few 
 
 moments, and in a little time there is a quite good octahe- 
 dral deposit, very similar to that from a 100th solution of 
 potash (Plate I, fig. 1). 
 
 4. TFo grain: crystals appear in less than half a minute, and 
 
 in a little time they are quite copious. 
 
 5. Tso' grain: in about three minutes crystals are just percep- 
 
 tible; in about five minutes the deposit is quite satisfac- 
 tory. The formation of the precipitate is somewhat 
 hastened by stirring the mixture with a glass rod. 
 
 6. i,o\o grain: in about eight minutes crystals are perceptible 
 
 to the microscope, and soon after they become quite obvi- 
 ous to the naked eye, especially along the margin of the 
 mixture; after about half an hour there is a quite satis- 
 factory deposit. 
 Solutions but little more dilute than the last-mentioned fail 
 to yield a precipitate even after many hours. 
 
 Fallacies. — The method of distinguishing the double chloride 
 of ammonium and platinum from the corresponding potassium 
 compound, has already been pointed out under the special con- 
 sideration of the latter {ante, p. 76). This reagent fails to pro- 
 duce a precipitate even in the most concentrated solutions of 
 soda. 
 
 2. Tartaric Acid, and Tartrate of Soda. 
 
 These reagents produce in neutral solutions of ammonia, 
 when not too dilute, a white crystalline precipitate of tartrate 
 
SPECIAL CHEMICAL PROPERTIES. 91 
 
 of ammonia (NH4O, HO, C3H4O10), which in appearance is very 
 similar to the corresponding salt of potash, but somewhat more 
 soluble in water. It is soluble in the free alkalies and in dilute 
 mineral acids. 
 
 1. sV grain of the alkali yields with free tartaric acid no im- 
 
 mediate precipitate, but in a little time crystals begin to 
 separate, and after a few minutes there is a very satis- 
 factory deposit, the crystals having the same form as those 
 from potash, Plate I, fig. 2. The acid tartrate of soda 
 produces much the same results, but the form of the crys- 
 tals is then similar to those illustrated in Plate I, fig. 3. 
 
 2. Yo^o" grain: after several minutes granules and small crystals 
 
 appear, and after some minutes more, there is a quite 
 good crystalline deposit, chiefly confined however to the 
 margin of the mixture. With tartrate of soda, the pre- 
 cipitate is more prompt in appearing and becomes more 
 abundant; the forms of the crystals are then the same as 
 before by this form of the reagent. 
 
 3- 2^ grain: after ten or fifteen minutes, some few granules 
 form along the margin of the mixture; in about half an 
 hour the deposit becomes quite satisfactory. The soda 
 reagent produces a more prompt and satisfactory reaction. 
 The formation of the precipitate from this, as well as 
 from the preceding solutions, is much facilitated by stir- 
 ring the mixture. 
 
 4. 5-ro grain, yields with tartrate of soda, after stirring the 
 mixture some minutes, a distinct granular deposit, which 
 after a time becomes quite satisfactory. 
 There is nothing in the physical appearance of the tartrate 
 
 of ammonia to distinguish it from the corresponding precipitate 
 
 produced from solutions of potash. 
 
 \ 
 
 3. Garhazotic Acid. 
 
 An alcoholic solution of carbazotic acid produces in neutral 
 solutions of salts of ammonia, a yellow crystalline precipitate 
 of carbazotate of ammonia, which is insoluble in excess of the 
 reagent. 
 
92 AMMONIA. 
 
 1- To grain of the alkali yields an immediate amorphous pre- 
 cipitate, which in a little time becomes a mass of yellow 
 crystals. The form of the crystals is quite different from 
 that of those produced by the reagent from solutions of 
 either of the fixed alkalies. 
 
 2. yj^ grain: almost immediately crystals begin to separate, 
 
 and in a little time there is a quite good deposit. Under 
 the microscope, the crystals present the appearances illus- 
 trated in Plate I, fig. 5, which readily distinguish them 
 from the corresponding salts of potash and soda. 
 
 3. Tso grain: in a few moments small rough needles begin to 
 
 form, and very soon there is a good crystalline precipitate, 
 in form quite unlike that from potash. 
 
 4. Toi) grain: in a few minutes needles begin to separate along 
 
 the margin of the drop, and after a little time there is a 
 satisfactory deposit. 
 5- T5~o grain: after some minutes, small needles appear; after 
 some minutes more, there is a quite satisfactory deposit 
 of needles, plates and cubes, which might readily be con- 
 founded with the deposit from dilute solutions of potash. 
 
 4, Nessler's Test. 
 
 The author of this test has shown that when a solution of 
 iodide of potassium and iodide of mercury in excess of free 
 potash, is acted upon by ammonia, the latter is decomposed 
 with the production of an insoluble compound, which has been 
 designated tetrahydrargyro-iodide of ammonium (NHgil, 2 HO) 
 (Chemical G-azette, xiv, pp. 445, 463). 
 
 The test fluid is prepared by dissolving 20 parts by weight 
 of pure iodide of potassium in 50 parts of water, and adding 
 pure iodide of mercury to the warmed mixture until it is no 
 longer dissolved, which will require about 30 parts of the 
 mercury salt. The double iodide of potassium and mercury 
 (Hgl, KI), requires for its formation only .27-3 p^irts of iodide 
 of mercury to 20 parts of iodide of potassium ; so it seems that 
 more than one equivalent of the mercury iodide wUl under 
 these circumstances dissolve in one of the iodide of potassium. 
 
SPECIAL CHEMICAL PROPERTIES. 93 
 
 The cooled solution is then diluted with three times its volume 
 of pure water, and the mixture allowed to stand some hours, 
 when the excess of iodide of mercury will separate in its crys- 
 talline form. The fluid is then filtered, and two measures of 
 the filtrate mixed with three measures of a concentrated solu- 
 tion of caustic potash, and this mixture employed as the rea- 
 gent. If the Kquid becomes turbid upon the addition of the 
 potash solution, it should again be filtered. 
 
 The reagent prepared as above, produces the following 
 results : 
 
 !• TW grain of ammonia as chloride, in one grain of water, 
 yields a very copious, beautiful orange-colored amorphous 
 precipitate, most of which dissolves, with the production 
 of a colorless solution, in excess of free ammonia, and of 
 chloride of ammonium, leaving a slight, cream-colored 
 residue. It is readily soluble to a colorless solution, in 
 hydrochloric acid. 
 
 2. 1 0^0 grain, yields a quite copious precipitate, having a fine 
 
 orange color. 
 
 3. 10,000 grain: a very good, reddish-yellow deposit. Five 
 
 grains of the solution, yield a fine orange precipitate. 
 
 4. 50,000 grain: an immediate yellow turbidity, which very 
 
 soon assumes an orange tiat, followed by a good flocculent 
 precipitate, having a light-yeUow color. Ten grains of 
 the solution, with a drop of the reagent, yield an almost 
 immediate, orange-colored muddiness, which slowly sub- 
 sides to a deposit of the same color. 
 5- 10 0^*0 grain: an immediate cloudiness, and in a very little 
 time the mixture contains suspended flakes, which have a 
 dirty-white color. Five grains of the solution yield a 
 bright-yellow turbidity, and soon the mixture acquires a 
 slight orange tint. 
 
 6. 5oo!'ouo grain: after a little time, a just perceptible cloudi- 
 
 ness. Five grains of the solution very soon assume a 
 pale-yeUow color, which on heating the mixture is changed 
 to a very slight orange hue. 
 
 7. ],o 0^0,0 grain: five grains of the solution after a little 
 
 time assimie a very pale-yeUow color, which on the appU- 
 
94 AMMONIA. 
 
 cation of heat is changed into the slightest perceptible 
 tint of orange. The color of this, and other dilute solu- 
 tions, is best seen by transmitted light. 
 The extreme sensibiKty of this test is explained by the cir- 
 cumstance that 17 parts by weight of ammonia yield 559 parts 
 of the mercury compound, in accordance with the following 
 reaction : 
 
 NH3 + 4 Hgl, KI + 3 KO = NHgJ, 2 HO + 7 KI + HO. 
 According to the discoverer of this test, the presence of 
 alkaline chlorides and oxysalts have no injurious influence upon 
 the reaction of the reagent; and iodide of potassium is only 
 injurious when sufficient caustic potash has not been added. 
 But the reaction is not produced in the presence of cyanide of 
 potassium and sulphuret of potassium, even in concentrated 
 solutions of ammonia and the presence of great excess of potash. 
 
 Phospho-moltbdate of Soda, according to Sonnenschein 
 (Chem. Gaz., x, 411), will readily detect the presence of one 
 part of chloride of ammonium in 10,000 parts of water. The 
 reagent is prepared, by igniting the yellow precipitate produced 
 by adding molybdate of ammonia to an acidulated solution of 
 phosphate of soda, to expel the ammonia; any molybdic acid 
 reduced in this operation, is reoxidised by nitric acid, the ex- 
 cess of which is expelled by heat. The residue is then dis- 
 solved in carbonate of soda, the solution supersaturated with 
 hydrochloric acid, and the mixture heated, after which any 
 precipitate that has formed is redissolved by the addition of 
 more acid. 
 
 This liquid, when employed as a reagent, produces in 
 solutions of salts of ammonia a yellow precipitate of phos- 
 pho-molybdate of ammonia, which according to Sonnenschein, 
 contains only 6-747 per cent, of oxide of ammonium. The 
 reagent produces a similar yellow precipitate in tolerably con- 
 centrated solutions of salts of potash; but it fails to precipitate 
 solutions of salts of soda. 
 
 Antimoniate of Potash produces no precipitate, even in con- 
 centrated solutions of salts of ammonia or of the free alkali. 
 
SEPARATION FROM ORGANIC MIXTURES. 95 
 
 Separation from Organic Mixtures. 
 
 Unless the ammonia be present only in extremely small 
 quantity or combined with an acid, the liquid will have an 
 alkaline reaction and give out the odor of the alkali. Ammonia 
 and its carbonate, may be separated from organic solutions, by 
 distilling the liquid at a moderate heat, in a retort, the beak 
 of which is provided with a perforated cork carrying a smaU 
 tube, which is bent at an obtuse angle and made to dip beneath 
 the surface of a very small quantity of pure water, contained 
 in a weU-cooled receiver. Any of the alkali or its carbonate 
 present, will be vaporised by the heat and pass along with the 
 vapor of water into the receiver; the solution thus obtaiaed 
 may be tested in the ordinary manner. 
 
 If after distilling over about one-eighth of the contents of 
 the retort, no ammonia yet appear in the distillate, it may be 
 concluded that none of the free alkali or its volatile salt is 
 present. It may however be present in the form of some of 
 its more fixed salts. To ascertain this, the contents of the 
 retort are treated with strong alcohol, which will in part at 
 least, coagulate the organic matter; the mixture is then filtered, 
 the filtrate treated with caustic potash or hydrate of lime, and 
 distilled as before. Any ammoniacal salt present, will now be 
 decomposed by the alkali added, with the evolution of free am- 
 monia, which will appear in the distillate. In some instances, 
 it is best to replace the pure water placed in the receiver, by 
 a very dilute solution of hydrochloric acid, whereby the am- 
 monia will be more effectually absorbed, in the form of chloride 
 of ammonium. 
 
 If the mixture under examination contains organic matter 
 in a state of decomposition, this may give rise to ammonia. In 
 mixtures of this kind, it may be difficult or even impossible, to 
 decide the true source of the poison. If it be the contents of 
 the stomach that are thus examined, the quantity of the alkali 
 recovered and the post-mortem appearances, may readily decide 
 its origin. 
 
96 AMMONIA. 
 
 Quantitative Analysis. — This may be effected by precip- 
 itating the alkali in the form of double chloride of ammonium 
 and platinum, and treating the precipitate in the same manner 
 as directed for the estimation of potash {ante, p. 82). The 
 double ammonium salt contains 7-62 per cent, by weight of 
 pure ammonia (NH3). 
 
 Every 17 grains of real ammonia correspond to 52-6 grains 
 of the most concentrated aqua ammonice, which measure a few 
 drops over one fluid drachm. 
 
THE MINERAL ACIDS. 97 
 
 CHAPTEE II. 
 
 THE MINERAL ACIDS: SULPHURIC, NITRIC, AND HYDRO- 
 CHLORIC. 
 
 General Natuee and Effects. — The above-named mineral 
 acids, form a group of compounds the members of which are 
 quite similar, both in respect to their general chemical proper- 
 ties and their effects upon the animal system. They possess 
 the property of acidity in the most eminent degree, such as 
 reddening blue litmus, perfectly neutralising free alkalies, and 
 decomposing the salts of other acids. They are more or less 
 decomposed when brought in contact with many of the metals, 
 such as zinc, iron, copper, and mercury, with the formation of 
 their respective salts. Sometimes this decomposition takes 
 place at ordinary temperatures, but at others, only upon the 
 application of heat. Most of the salts of these acids are read- 
 ily soluble in water. 
 
 In their powers to corrode and destroy organic substances, 
 the mineral acids stand preeminent. When brought, in their 
 somewhat con.centrated state, in contact with living animal tis- 
 sues, they rapidly destroy their organisation and vitality; in 
 this manner they may speedily occasion death by their direct 
 chemical action. Due to this action, they also speedily affect 
 or entirely destroy various articles of clothing with which they 
 come in contact: this property is sometimes of considerable 
 importance in a medico-legal point of view. 
 
 Numerous instances are recorded in which these substances 
 occasioned death; but with few exceptions, the poison was 
 taken either with suicidal intent or as the result of accident. 
 In fact, from their immediate and powerfully corrosive action 
 on the mouth, there is perhaps no poison which, for criminal 
 purposes, could not be resorted to with greater safety from 
 
98 SULPHURIC ACID. 
 
 detection than either of these acids; yet cases are not wanting 
 in which they were thus employed. 
 
 Section I. — Sulphuric Acid. 
 
 This acid has long been known under the name of oil of 
 vitriol, which name it received from the fact that it was pre- 
 pared from green vitriol, or sulphate of iron. As met with in 
 the shops, it is a dense, powerfully acrid and corrosive, oily 
 liquid, with usually a more or less brownish color. When 
 brought in contact with organic substances, it speedily chars 
 them. In proportion as it is diluted with water, it loses its 
 oily appearance and power of acting upon organic tissues. As 
 a poison, it has been principally used in the form of the com- 
 mercial acid, yet instances of poisoning by sulphate of indigo, 
 which is a solution of indigo in the concentrated acid, and 
 by aromatic sulphuric acid of the Pharmacopoeias, have also 
 occurred. 
 
 Instances of poisoning by this acid, have been of much more 
 frequent occurrence than by either of the other mineral acids. 
 But, as already intimated, it has rarely been administered crim- 
 inally. Of twelve cases of poisoning by this substance recently 
 collected by Dr. Cozzi, in a hospital in Florence, eleven were 
 the result of suicide. Dr. Christison has collected several in- 
 stances in which children were murdered by the acid being 
 poured down the throat. A case is also reported in which a 
 man was murdered in a similar manner, while he lay asleep ; 
 and another, in which it was thus administered to a woman 
 while she was intoxicated. A singular practice of secretly 
 throwing the acid upon persons for the purpose of disfiguring 
 them or of destroying their dress, has been of not unfrequent 
 occurrence, both in this country and in Europe. 
 
 Symptoms. — The direct effects of sulphuric acid will, of 
 course, depend much upon the degree of its concentration, and 
 the quantity taken. When taken in its concentrated state, all 
 the soft parts of the mouth and throat are immediately more or 
 less corroded and destroyed, and assume a white appearance; 
 
PHYSIOLOGICAL EFFECTS. 99 
 
 and, if the poison has been swallowed, the lining membrane of 
 the oesophagus and stomach, will be acted upon in the same 
 manner. These effects will be followed with intense burning 
 pain in the mouth, throat and stomach, alteration of voice, 
 gaseous eructations, and violent vomiting. The vomited mat- 
 ters have usually a brownish or black color, strongly acid prop- 
 erties, and contain disorganised membrane and blood. As the 
 case advances, there will be excruciating pain in the bowels, 
 impaired respiration, difficulty of swallowing, coldness of the 
 extremities, and great prostration. The pulse becomes weak 
 and irregular, the countenance ghastly, and the body covered 
 with cold perspiration. The bowels are usually much consti- 
 pated, and the urine scanty. The inside of the mouth and 
 throat frequently become covered with sloughs. The mental 
 faculties usually remain unimpaired. 
 
 Such are the symptoms usually observed in poisoning by 
 this acid ia its concentrated state, but it is obvious that they 
 may not aU be present in a given case. The vomiting, which 
 in most instances is either immediate or within a very short 
 period, has been delayed for half an hour or longer. The 
 action of the acid may be confined to the mouth, the poison 
 having been thrown out without any portion of it being swal- 
 lowed. In such cases, however, it may produce death by 
 asphyxia, from the closure of the air-passages. On the other 
 hand, the mouth may escape the local action of the acid, it 
 having been administered in a spoon passed back into the throat, 
 as in a case cited by Dr. Taylor. If the acid has come in 
 contact with the hps or other parts of the external skin, they 
 at first present a white appearance, which afterwards becomes 
 yellowish-brown. 
 
 When swallowed in its diluted state, the acid produces much 
 the same symptoms as those just described, only that they are 
 less prompt in appearing, and the local action of the poison is 
 less violent. The extent of this difference will, of course, de- 
 pend upon the degree of dilution of the acid. 
 
 Period when Fatal. — In fatal poisoning by this acid, death 
 usually takes place in from twelve to thirty-six hours; but this 
 event has occurred within an hour, and again, it has been 
 
100 SULPHURIC ACID. 
 
 delayed for weeks, and even months. Dr. Christison cites a 
 case in which a child, who, while attempting to swallow strong 
 sulphuric acid by mistake for water, died almost immediately, to 
 all appearances from suffocation caused by contraction of the 
 glottis; it was ascertained after death that none of the poi- 
 son had reached the stomach (Op. cit., p. 132). Mr. Traill 
 reports the case of a washerwoman, who took by mistake, a 
 wine-glassful of the commercial acid, having a specific gravity 
 of 1'833, and, although actively treated, died in one hour after- 
 wards. After death, a perforation was found in the stomach, 
 and the peritoneum was greatly inflamed, from the escape of 
 the acid from the stomach. An instance is also related by 
 Prof. Casper, in which the poison, administered by an unnatu- 
 ral mother to her own child, aged one year and a half, caused 
 death, in spite of the antidotes administered, in one hour (Fo- 
 rensic Medicine, ii, p. 75). These are the most rapidly fatal 
 cases yet recorded. Not less than three cases, however, are 
 reported, in which death occurred in tivo hours ; and several, 
 in which death took place in from three to five hours. 
 
 In poisoning by this substance, as in the case of the caustic 
 alkalies, the patient may recover from the immediate effects of 
 the poison, and yet die from secondary causes, long periods 
 afterwards. In such cases, nervous symptoms and general de- 
 rangement of the assimilating organs usually manifest them- 
 selves, and death is the result, either of chronic inflammation 
 of the stomach and bowels, or of stricture of some part of the 
 alimentary tube. Several instances are reported in which death 
 did not take place until from the fifteenth to the twentieth day 
 after the poison had been taken; and Dr. Beck quotes a case, 
 not fatal until after the lapse of tivo months. In an instance 
 reported by Dr. Wilson, life was prolonged for over ten months. 
 During the progress of this case, the thickened lining mem- 
 brane of the oesophagus came away in the form of a firm cylin- 
 drical tube, eight or nine inches in length. The most protracted 
 case in this respect yet recorded, is that quoted by Dr. Beck 
 (Med. Jur., ii, 472), in which the patient survived the taking 
 of the poison, two years, when death supervened from the 
 effects of stricture of the oesophagus. 
 
ANTIDOTES. 101 
 
 Fatal Quantity. — The effects of given quantities of sulphuric 
 acid, have by no means been uniform. They will be influenced 
 much by the condition of the stomach, as to the presence of 
 food, and the degree of concentration of the acid, as also, of 
 course, on the promptness with which remedies are employed. 
 In many instances, it is difficult to determine exactly how much 
 of the poison has been retained in the body, even when the 
 quantity originally taken is accurately known, since much of it 
 is often rejected from the mouth as soon as taken. 
 
 The smallest fatal dose yet recorded, is in a case quoted by 
 Dr. Christison, in which half a teaspoonful or about thirty 
 minims of the concentrated acid, caused the death of a child 
 one year old, in twenty-four hours. The same writer quotes 
 another instance, in which one drachm, taken by a stout young 
 man, proved fatal in seven days (Op. cit., p. 131). In a case 
 already mentioned, about one drachm and a half of the acid, 
 poured into the mouth of a man while asleep, caused death in 
 forty-seven hours. 
 
 On the other hand, recovery has not unfrequently taken 
 place, after large doses of the acid had been swallowed. Thus, 
 not less than two instances of this kind are related, in each of 
 which tivo ounces of the concentrated acid had been taken. 
 And Dr. Beck quotes a case, in which a man recovered after 
 having swallowed four ounces (whether by weight or measure 
 not stated). This is the largest dose that we find recorded, 
 from which there was recovery. 
 
 Treatment. — There are many substances that wiU perfectly 
 neutralise this acid, yet on account of its very rapid local action, 
 at least in its concentrated state, it is not often that chemical 
 antidotes can be administered sufficiently early to prevent seri- 
 ous injury. Common chalk and calcined magnesia, suspended 
 in mUk, have generally been recommended, and wiU. answer the 
 purpose very weU. The alkaline carbonates, properly diluted 
 with water or milk, have also been strongly advised, and are 
 perhaps preferable. In the administration of the alkaline car- 
 bonates, it must be remembered that they themselves in large 
 quantities, are highly poisonous. Oily emulsions, soap-suds, 
 and milk alone, may be employed with advantage. 
 
102 SULPHURIC ACID. 
 
 Several instances are related, in which the timely adminis- 
 ti-ation of one or other of these antidotes saved the life of the 
 patient, even after very large quantities of the poison had been 
 taken. The exhibition of the antidote, shoidd always be fol- 
 lowed by large draughts of tepid water or demulcent fluids, to 
 promote vomiting. The whole of the acid, however, may be 
 neutralised and removed from the stomach, and yet death take 
 place from the effects of its primary action. On account of this 
 local action, the patient is sometimes unable to swallow when 
 first seen by the physician. Under these circumstances the 
 poison may be withdrawn by means of the stomach-pump; but, 
 for obvious reasons, this instrument should be used with great 
 caiition, and employed only as a final resort. 
 
 Post-mortem Appeaeances. — In poisoning by sulphuric 
 acid, the pathological appearances are more frequently peculiar 
 and characteristic, than, perhaps, in the action of any other 
 poison. These appearances, however, will be much modified 
 by the degree of concentration of the acid, and the length of 
 time the patient survived after it had been taken. In the tak- 
 ing of the poison it not unfrequently happens that drops of it 
 become sprinkled over the face, neck, and other portions of the 
 skin; in such cases, if not very protracted, these parts will 
 present dark-brown spots or stains. In the case cited above 
 from Casper, in which death took place in an hour, dirty- 
 yellow parchment-hke streaks, arising from the trickling down 
 of the acid, extended from the angle of the mouth to the ear; 
 similar stains were present on the arms and hands of the child. 
 The tongue was white and leathery, and had no acid reaction. 
 The stomach, both externally and internally, was quite grey, 
 and filled with dark, bloody, acid mucus; its tissues fell to 
 pieces when touched; the vena cava was moderately filled with 
 a cherry-red syrupy and acid blood; and the liver and spleen 
 were congested with blood of the same character ; the heart con- 
 tained only a few drops of blood. The tissues of the oesophagus 
 were quite firm, and its mucous membrane had a greyish color, 
 and an acid reaction; the larynx and trachea were normal. 
 
 In recent cases, the mucous membrane of the tongue and of 
 the mouth, is generally more or less corroded, and of a white. 
 
POST-MORTEM APPEARANCES. 103 
 
 but sometimes of a deep-brown color; in some instances large 
 patches of this membrane are entirely destroyed. Similar ap- 
 pearances are usually found in the fauces, and throughout the 
 length of the cesophagus. The lining membrane of this organ, 
 is sometimes much thickened and partially detached. Instances 
 are recorded, however, in which the mouth and cesophagus pre- 
 sented but few signs of the local action of the poison. 
 
 The stomach generally presents a brownish or black appear- 
 ance, due to the carbonising action of the acid ; its bloodvessels 
 are frequently much engorged with dark coagulated blood, and 
 its tissues so soft as to be readily lacerated, even by the slight- 
 est pressure. Sometimes this disorganisation is confined to 
 patches, whilst in others, it extends in the form of lines or 
 streaks; often the pylorus presents the most decided marks of 
 disorganisation. The contents of the stomach are usually thick 
 and have a brownish or charred appearance and a highly acid 
 reaction. If the stomach become perforated, as nOt unfre- 
 quently happens, the acid may escape and exert its chemical 
 action upon the surrounding organs ; but this organ may become 
 perforated and its contents not escape. The aperture of the 
 perforation, usually presents a roundish appearance, and has 
 thin, black, irregular edges. Sometimes there are several such 
 perforations. In one instance, the perforation measured about 
 three inches in diameter, and was bordered by thickened edges 
 of a dark-brown, cinder-like appearance. A few instances 
 have occurred, in which there were no marks of the chemical 
 action of the poison, except in the neighborhood of the per- 
 foration. 
 
 The duodenum .and other portions of the small intestines, 
 have in some instances presented signs of corrosion similar to 
 those observed in the stomach. Instances are reported, how- 
 ever, in which there was little or no abnormal change in these 
 organs, even when the stomach was extensively disorganised. 
 
 In making these examinations, the inspector should not for- 
 get, that the action of the acid may be confined to the mouth 
 and throat, none of the poison having passed into the stomach. 
 In such cases, as also in others, the air-passages may be much 
 corroded and inflamed. So also, it should be remembered, that 
 
104 SULPHURIC ACID. 
 
 when the acid is swallowed in its diluted state, or the stomach 
 contains much food or liquid, this organ may present simply 
 signs of inflammation, instead of the disorganised appearances 
 described above; even when, however, the acid is much diluted, 
 the inside of the stomach may present a blackened appearance. 
 
 In a number of cases of acute sulphuric acid poisoning 
 examined by Prof. Casper, the blood had in every instance a 
 cherry-red color, a more or less ropy consistency, and an acid 
 reaction. He also relates an instance of similar poisoning, in 
 which he found the pericardial and amniotic fluids of a decid- 
 edly acid reaction, the person poisoned being pregnant (Foren- 
 sic Medicine, ii, pp. 58, 83). In the case of another pregnant 
 woman, quoted by Dr. Beck (Med. Jur., ii, 475), the amniotic 
 fluid, as well as that found in the pleura, peritoneum, heart, 
 and bladder of the foetus, had an acid reaction. It need hardly 
 be remarked that this acid condition of the fluids of the body, 
 would only be found in recent cases. 
 
 According to Casper, the bodies of persons poisoned by this 
 acid, and perhaps by the other mineral acids, remain fresh and 
 without odor for an unusual length of time. He attributes this 
 condition to the free acid neutralising the ammonia evolved 
 during the first stages of the process of putrefaction. 
 
 When the patient survives the primary efi'ects of the poison 
 and dies from secondary results, the appearances will, of course, 
 difi'er from those described above. In such cases, the body is 
 usually extremely emaciated, and one or more portions of the 
 alimentary canal much contracted. In Dr. Wilson's case, in 
 which life was protracted for over ten months, the upper third 
 of the oesophagus shone like an old cicatrix, and the lower 
 two-thirds were thickened, narrowed, and very vascular; the 
 stomach contained a perforation, which was surrounded with 
 softened edges. 
 
 Chemical Peopeeties. 
 
 Geneeal Chemical Nature. — Anhydrous sulphuric acid, 
 which is a compound of one equivalent of Sulphur with three 
 equivalents of Oxygen (SO3), is a very rare, white crystaUine 
 
GENERAL CHEMICAL NATURE. 
 
 105 
 
 substance, apparently destitute of acid properties. It melts 
 to a clear liquid at about 65°, and boils at about 115° F., being 
 dissipated in the form of a colorless vapor. It has an intense 
 aifinity for water, with which it unites with violence, forming 
 the ordinary hydrated acid. 
 
 The most concentrated form in which this acid is found in 
 commerce, is usually a definite chemical combination of one 
 equivalent of the so-called anhydrous acid with one equivalent 
 of water (HO, SO3). In this state, when pure, it is a color- 
 less, odorless, highly acrid, corrosive, oily liquid, having a 
 specific gravity of 1-845, and containing 81-6 per cent, of the 
 anhydrous acid; it boils at a temperature, of 620°, and freezes 
 at — 29° F. In certain respects, this hydrated compound is 
 the most powerful acid known. It has a strong attraction for 
 water, which it readily absorbs from the atmosphere; it mixes 
 with this liquid in all proportions, with a contraction of volume, 
 and the evolution of much heat. In proportion as it is mixed 
 with water, it loses its oily consistency and becomes specific- 
 ally lighter; when diluted to a density of 1-5 its oily appear- 
 ance will have about disappeared, and it will have a less 
 energetic action upon organic substances. The density of the 
 diluted liquid, when pure, indicates the amount of real acid 
 present. 
 
 The following table, abridged from that first constructed by 
 Dr. Ure, indicates the per cent, by weight of anhydrous (SO3), 
 and monohydrated acid (HO, SO3), in pure solutions of different 
 specific gravities : — 
 
 STRENGTH OF AqUEOUS SOLUTIONS OF SULPHURIC ACID. 
 
 
 Percentage of 
 
 
 Percentage of 
 
 
 Percentage of 
 
 Specific 
 Gravity. 
 
 
 
 Specific 
 Gravity. 
 
 
 
 Specific 
 Gravity. 
 
 
 
 
 
 
 
 
 SO3. 
 
 HO, SO3. 
 
 
 SO3. 
 
 HO, SO3. 
 
 
 SO3. 
 
 HO, SO3. 
 
 1-848 
 
 81-54 
 
 100 
 
 1-539 
 
 63-00 
 
 65 
 
 1-218 
 
 24-46 
 
 30 
 
 1-837 
 
 77-46 
 
 95 
 
 1-486 
 
 48-92 
 
 60 
 
 1-179 
 
 20-38 
 
 25 
 
 1-811 
 
 73-39 
 
 90 
 
 1-436 
 
 44-85 
 
 56 
 
 1-141 
 
 16-31 
 
 20 
 
 1-767 
 
 69-31 
 
 85 
 
 1-388 
 
 40-77 
 
 50 
 
 1-101 
 
 12-23 
 
 16 
 
 1-712 
 
 65-23 
 
 80 
 
 1-344 
 
 36-69 
 
 45 
 
 1-068 
 
 8-15 
 
 10 
 
 1-652 
 
 61-15 
 
 75 
 
 1-299 
 
 32-61 
 
 40 
 
 1-033 
 
 4-08 
 
 6 
 
 1-697 
 
 57-08 
 
 70 
 
 1-257 
 
 28-64 
 
 36 
 
 1-007 
 
 0-81 
 
 1 
 
106 SULPHURIC ACID. 
 
 The acid of commerce has frequently a dark-brown color, 
 due to its having been brought in contact with organic matter. 
 Sulphuric acid quickly chars animal and vegetable substances; 
 when dropped, even in a much diluted state, on black woolen 
 cloth, it causes it to assume a red color, which after a time 
 fades to brown. Many substances, such as certain metals, 
 charcoal and various organic compounds, when heated with the 
 concentrated acid, decompose it with the evolution of sulphur- 
 ous acid gas (SOj). In a diluted state, in the presence of 
 some of the metals, such as zinc, it decomposes water, at the 
 ordinary temperature, with the evolution of hydrogen gas and 
 the formation of a salt of the oxide of the metal. 
 
 The salts of sulphuric acid are usually colorless, and for the 
 most part readily soluble in water. The sulphates of the fixed 
 alkalies and of the alkaline earths are unchanged by a red heat, 
 but most other sulphates readily undergo decomposition when 
 strongly ignited. When thoroughly mixed and ignited with 
 either charcoal or a mixture of carbonate of soda and cyanide 
 of potassium, or with ferrocyanide of potassium, all metallic 
 sulphates are readily decomposed with the formation of a sul- 
 phuret of the metal. This residue when acted upon by hydro- 
 chloric acid, evolves sulphuretted hydrogen gas, with the for- 
 mation of a chloride of the metal. 
 
 Special Chemical Peopeeties. — When in its concentrated 
 state, sulphuric acid may be readily recognised by the proper- 
 ties already mentioned, such as its carbonising action on organic 
 matter, evolving heat when mixed with water, etc. ; but when 
 in a diluted state, its presence has to be determined by other 
 tests. The acid has the property of reddening veratrine, pip- 
 erine, phloridzine, oil of bitter almonds, and several other or- 
 ganic compounds. On account of the solubility of most of the 
 compounds of sulphuric acid, there are but few reagents that 
 precipitate it from solution ; however, there is no substance that 
 can be detected with greater certainty and ease than this acid. 
 
 The presence of free sulphuric acid in solution with a sul- 
 phate may be recognised by adding a little cane sugar and 
 evaporating the mixture to dryness at 212° F., when, if the 
 free acid be present, the residue has a black color, due to the 
 
SPECIAL CHEMICAL PROPERTIES. 107 
 
 charring action of the acid; if only a trace of it be present, 
 the residue will have a blackish-green color. No other free 
 acid behaves in this manner with cane sugar (Runge). 
 
 In the examination of the following tests, aqueous solutions 
 of pure sulphuric acid were chiefly employed. The fractions 
 refer to the amount of monohydrated sulphuric acid (HO, SO3) 
 present in one grain of the solution; and the results, unless 
 otherwise stated, to the behavior of one fluid-grain of the 
 solution. 
 
 1. Chloride of Barium. 
 
 Chloride of barium, and the Nitrate of baryta, produce in 
 solutions of free sulphuric acid, and of its salts, an immediate 
 white precipitate of sulphate of baryta (BaO, SO3), which is 
 insoluble in free acids and in the caustic alkalies. In applying 
 this test to neutral solutions for the detection of combined Sul- 
 phuric acid, the solution should first be acidulated M'ith either 
 hydrochloric or nitric acid. 
 
 1. xoir grain of protohydrated sulphuric acid in solution in one 
 
 grain of water, yields with either of the above reagents, 
 an immediate, copious precipitate, which, if the mixture 
 be not much agitated, consists of feathery steUate crystals, 
 needles, and granules, Plate II, fig. 4. The same crystal- 
 line deposit may be obtained from the acid when in solu- 
 tion in the form of a stJphate ; at least from the sulphates 
 of potash, soda, ' magnesia, and copper. If the mixture be 
 much agitated on the addition of the reagent, the precip- 
 itate is whoUy in the form of very small granules. The 
 precipitate, whether crystalline or otherwise, remains un- 
 changed on the addition of several drops of concentrated 
 hydrochloric acid. 
 
 2. TToou grain, yields a rather copious, principally amorphous 
 
 but partially granular precipitate. 
 
 3. 5,0 ou grain : an immediate amorphous deposit. 
 
 4. 10,000 grain : after a very little time, there is a very good 
 
 precipitate. A drop of the sulphuric acid solution imme- 
 diately reddens litmus-paper. 
 
 5. 2 5.000 grain : an immediate turbidity, and after a little time, 
 
108 SULPHURIC ACID. 
 
 a very satisfactory deposit. A drop of this solution faintly 
 reddens litmus-paper. 
 
 6. T o'.ws grain : very soon, the mixture is distinctly turbid, 
 and after several minutes it yields a quite distinct precip- 
 itate. This solution just perceptibly changes the color of 
 normal litmus-paper. 
 
 "• 10 0% grain : after some minutes, a distinct deposit, which 
 is usually, especially when nitrate of baryta is employed as 
 the reagent, granular. 
 
 8- 2"o"oTooT) grain: in about one minute there is a perceptible tur- 
 
 bidity, which after several minutes becomes quite distinct. 
 
 9- T oo%oo grain, yields after from ten to fifteen minutes, a just 
 
 perceptible cloudiness. This result is equally produced by 
 either of the baryta reagents. 
 
 The last-mentioned quantity of sulphuric acid would form 
 the^ 168,000th part of a grain of sulphate of baryta. It is ob- 
 vious therefore, especially as there was some fluid added with 
 the reagent, that this salt requires more than 168,000 times its 
 weight of water for solution. There has been much discrepancy 
 among observers in regard to the limit of this test, and the sol- 
 ubility of the baryta compound. Thus, Harting placed the limit 
 for chloride of barium, at one part of anhydrous sulphuric acid 
 in 75,000 parts of water; while Lassaigne placed it, for nitrate 
 of baryta, at one part of the acid in 200,000 parts of water, 
 after from ten to fifteen minutes (Gmelin's Handbook, vol. ii, 
 pp. 177, 192). Again, Gmelin states (upon the authority of 
 Klaproth?) that the sulphate of baryta is soluble in 43,000 
 parts of water (Handbook, iii, 152); whereas, Bischof concludes 
 from his experiments (Chem. and Phys. Geol., i, 450), that this 
 salt requires something more than 209,424 times its weight of 
 water for solution. 
 
 Confirmation of the Test. — If the sulphate of baryta, precip- 
 itated by this reagent, be dried, then thoroughly mixed with 
 about twice its weight of powdered charcoal or of a well-dried 
 mixture of equal parts of carbonate of soda and cyanide of 
 potassium, and the mixture heated to redness, for convenience 
 on platinum-foil, the baryta salt yields up its oxygen and be- 
 comes reduced to sulphuret of barium (BaS). This same 
 
SPECIAL CHEMICAL PROPERTIES. 109 
 
 conversion may be effected in a similar manner by ferrocyanide 
 of potassium, as first advised by Dr. E. Davy for the reduction 
 of arsenical compounds, and afterwards applied by Dr. Taylor 
 for the present purpose ; the salt should be previously pulverised 
 and thoroughly dried at 212° in a water-bath. Before using 
 either of these reducing agents for the reduction of the baryta 
 precipitate, a portion of the agent should be ignited alone, and 
 then tested for a sulphuret, in the manner about to be described ; 
 this precaution is necessary, since the agent itself might con- 
 tain a sulphate. In the absence of platinum-foil or a small 
 platinum or porcelain crucible, the ignition of the sulphate mix- 
 ture may be performed in an ordinary reduction-tube. 
 
 The presence of a sulphuret in the ignited sulphate mixture, 
 may be shown by moistening the cooled residue with diluted 
 hydrochloric acid, when it will evolve sulphuretted hydrogen 
 gas. The presence of this gas may be recognised by its . pe- 
 culiar odor, and by imparting a brown color to a slip of bibu- 
 lous paper, previously moistened with a solution of acetate of 
 lead and exposed to it. Or, the evolved gas may be conducted 
 into a solution of acetate of lead, when it will produce a black 
 precipitate of sulphuret of lead, or at least impart a brown 
 coloration to the solution. For this purpose, the cooled residue 
 is placed with a few drops of water, in a small test-tube. 
 Fig. 1, A, and treated with a few drops of rig. i. 
 
 hydrochloric acid, added by means of a small 
 funnel-tube, a; the evolved gas is conducted 
 through a delivery-tube, &, into a few drops of 
 the lead solution, acidulated with acetic acid, 
 contained in a second test-tube, B. By blow- 
 ing through the funnel-tube of the apparatus, 
 the last traces of the evolved gas will be 
 brought in contact with the lead solution. Apparatus for detecuou of 
 By this method, the sulphuretted hydrogen suiphuret of Barium. 
 evolved from the 100th part of a grain of sidphuric acid will 
 produce a distinct precipitate, and from the 1,000th of a grain, 
 a distinctly brown coloration. 
 
 So also, the ignited residue may be placed on a piece of 
 paper, which has previously been saturated with a lead solution 
 
110 SULPHURIC ACID. 
 
 and nearly dried, and then touched with a drop of diluted hy- 
 drochloric acid, when the moistened paper will assume a brown 
 color ; or, it may be placed in a watch-glass and moistened 
 with the acid, and another similar glass, containing a fragment 
 of paper moistened with the lead solution, inverted over this. 
 By either of these methods, especially the latter, the most mi- 
 nute traces of a sulphuret manifest themselves. 
 
 Fallacies. — Solutions of salts of baryta, also produce white 
 precipitates in solutions of Selenic and Hydrofluosilicic acids, 
 even in the presence of other free acids. Both these substances 
 are very rare, and only possible to be met with in medico-legal 
 investigations. The fluorine precipitate, at least from strong 
 solutions, is crystalline ; but the form of the deposit, Plate II, 
 fig. i, readily distinguishes it from the sulphate precipitate. 
 The seleniate of baryta is amorphous. This salt is soluble in 
 hot hydrochloric acid, with the evolution of free chlorine ; but 
 the silico-fluoride of barium is almost wholly insoluble in either 
 hydrochloric or nitric acid. Solutions of selenic acid, like those 
 of sulphuric acid, yield precipitates when treated with soluble 
 salts of strontium and of lead ; but the fluorine acid forms no 
 precipitate with solutions of these metals. The precipitate from 
 either of these acids would not, of course, yield a sulphuret 
 upon ignition with a reducing agent. 
 
 In applying this test it must also be borne in mind, that 
 when relatively large quantities of strong solutions of chloride 
 of barium, and of nitrate of baryta, are added to a liquid con- 
 taining much free hydrochloric acid or free nitric acid, it may 
 yield a white precipitate of the reagent saltj since these salts 
 are less soluble in a strong solution of either of these acids 
 than in pure water. Under these circumstances, however, the 
 precipitate would readily disappear on the addition of water ; 
 whereby it would be distinguished from the sulphate of baryta. 
 
 When the reagent is added to neutral or alkaline solutions, 
 it produces white precipitates with several acids other than 
 those already mentioned, such as carbonic, phosphoric, oxalic, 
 etc. ; but the precipitate produced from either of these, unlike 
 the sulphate of baryta, is readily soluble in hydrochloric and in 
 nitric acids. 
 
SPECIAL CHEMICAL PROPERTIES. Ill 
 
 2. Nitrate of Strontia. 
 
 This reagent produces in solutions of free sulphuric acid, 
 and of its salts, a white precipitate of sulphate of strontia 
 (SrO, SO3), which is quite perceptibly soluble in hydrochloric 
 and nitric acids, and much more soluble in water than the 
 corresponding baryta compound. From dilute solutions, the 
 formation of the precipitate is much promoted by warming the 
 mixture, and also by agitating it with a glass rod. 
 
 If the precipitate be collected and ignited with charcoal, or 
 any other reducing agent, it leaves a residue of sulphuret of 
 strontium, which may be recognised' as such in the same man- 
 ner as the sulphuret of barium. 
 
 1. Yo~o grain of free sulphuric acid, in one grain of water, yields 
 
 with the reagent a rather copious crystalline precipitate, 
 consisting of groups of exceedingly delicate transparent 
 needles, and granules, Plate II, fig. 6. The granules are 
 somewhat larger than those produced by the baryta 
 reagent. The deposit remains unchanged on the addition 
 of a few drops of hydrochloric acid. Similar results are 
 obtained from the acid when in solution in the form of a 
 sulphate. 
 
 2. i_ooo grain : an immediate cloudiness, and very soon a quite 
 
 good granular deposit. 
 
 3. 5,000 grain : in about one minute there is a perceptible 
 
 cloudiness, and in a few minutes, a good granular precip- 
 itate. 
 
 4. Y o.ooo grain : after a few minutes a distinct turbidity, and 
 
 after several minutes a quite satisfactory deposit. The 
 separation of the precipitate is much hastened by agitating 
 the mixture. 
 
 5. 20,000 grain, yields after several minutes a just perceptible 
 
 cloudiness, which increases but little, even after half an 
 hour. 
 Wackenroder states that the sulphate of strontia dissolves 
 slowly but completely, in a solution of common salt, in which 
 respect it diifers from the corresponding salt of baryta. 
 
112 SULPHURIC ACID. 
 
 The reaction of this test is subject to about the same falla- 
 cies as the preceding reagent. 
 
 3. Acetate of Lead. 
 
 Solutions of free sulphuric acid and of sulphates, yield with 
 this reagent a white amorphous precipitate of sulphate of lead 
 (PbO, SO3), which is sparingly soluble in dilute hydrochloric 
 and nitric acids. It is somewhat soluble in solutions of the 
 caustic alkalies, as also in some of the salts of ammonia. 
 !• Too" grain of the acid, yields a copious amorphous precipi- 
 tate, which in a large measure is dissolved on the addition 
 of a single drop of concentrated hydrochloric acid. 
 
 2. iTo'oo' grain : a rather copious precipitate, which on the addi- 
 
 tion of a drop of hydrochloric acid, very nearly all dis- 
 appears. 
 
 3. 10,000 grain, yields an immediate turbidity, and in a few 
 
 minutes a very satisfactory deposit. 
 
 4. 2' o,ooo grain : after some minutes a just perceptible turbidity, 
 
 which increases but little on standing. 
 This test is subject to many more fallacies than either of 
 those ah-eady mentioned. 
 
 4. Veratrine. 
 
 Veratrine, when added to a drop of concentrated sulphuric 
 acid, slowly assumes a yellow color and in a little time dissolves 
 to a beautiful crimson red solution. This solution is produced 
 immediately by warming the mixture. In the diluted acid, the 
 alkaloid dissolves slowly without change of color. 
 !■ TW grain : when a small quantity of the alkaloid is introduced 
 into one grain of a 100th solution of the free acid and heat 
 applied, it dissolves to a colorless mixture, which when 
 evaporated to dryness on a water-bath, leaves a beautiful 
 crimson-colored deposit. 
 2. 1,000 grain of the acid, when treated in a similar manner, 
 leaves a residue, the border of which has a fine crimson 
 color. 
 
SEPARATION FROM ORGANIC MIXTURES. 113 
 
 3. 5,0^0 grain: the residue has a just perceptible red tint, 
 which; however, is not well-marked. 
 
 Since this reagent produces no coloration with neutral sul- 
 phates, it serves to distinguish the uncombined acid from these 
 salts. And for this purpose we recommend it as much superior 
 in every respect to the cane-sugar method of Rimge. A drop 
 of a saturated solution of the neutral sulphate of either of the 
 fixed alkahes and of other similar salts, when treated with the 
 alkaloid and evaporated to dryness, failed to produce any red 
 coloration whatever. 
 
 This reaction is peculiar to the acid in question. 
 
 Othee Reactions. — Chloride of Calcium pi-oduces in some- 
 what concentrated solutions of free sulphuric acid and of its 
 salts, a white granular, but sometimes crystalline, precipitate 
 of sulphate of lime, which slowly disappears on the addition of 
 water, it being rather freely soluble in this fluid. One grain of 
 a 100th solution of the free acid, yields only a slight turbidity. 
 
 Metallic copper, when present in strong, boiling solutions of 
 sulphuric acid, decomposes it, with the evolution of sulphurous 
 acid gas, which may be recognised by its peculiar odor, and its 
 bleaching properties. This decomposition, however, does not 
 occur when the acid is diluted with as much as about ten times 
 its weight of water. So also, when not too dilute, the acid 
 decomposes, at ordinary temperatures, the sulphuret of iron, with 
 the evolution of sulphuretted hydrogen gas, known by its pecu- 
 liar odor and action on salts of lead. When the acid contains 
 about twenty-five times its weight of water, the decomposition 
 takes place very slowly; and when but little more diluted not 
 at aU. This decomposition, however, is common to several other 
 acids. 
 
 Separation from Organic Mixtures. 
 
 Suspected Solutions. — ^If the solution presented for examina- 
 tion be some article of drink, food or medicine, having a strong 
 acid reaction, and free from mechanically suspended matter or 
 solids, the tests for sulphuric acid may be applied at once, even 
 though the liqidd be highly colored. For this purpose, a given 
 
114 SULPHURIC ACID. 
 
 portion of the solution, after concentration if necessary, is treated 
 with a solution of chloride of barium as long as it produces 
 a precipitate. The mixture is then warmed and the deposit 
 collected on a filter, well washed with water containing pure 
 hydrochloric acid, and dried. If the mixture, containing the 
 precipitate, be so strongly acid that it perforates the filter, the 
 latter is supported on a muslin cloth, or the solution is diluted 
 before filtration. 
 
 When an organic mixture thus yields with chloride of barium 
 a white precipitate, which is insoluble in hydrochloric acid, there 
 is scarcely a doubt of the presence of sulphuric acid, either free 
 or otherwise. It is more satisfactory, however, to ignite a portion 
 of the dried precipitate with a reducing agent and determine 
 the presence of a sulphuret in the residue, in the manner already 
 pointed out. When this examination yields positive results, 
 there is no longer any doubt whatever of the presence of the 
 acid. The reactions of this test may, however, be confirmed by 
 examining other portions of the solution by some of the other 
 tests for the acid. 
 
 If the mixture presented for examination contain much solid 
 organic matter, it should, after dilution if necessary, be kept at 
 a boihng temperature for ten or fifteen minutes, then, when 
 cooled, filtered, and the sohds on the filter well washed with 
 warm water. The filtrate thus obtained is properly concentrated 
 and examined in the manner just described. 
 
 Although in this manner the presence of sulphuric acid may 
 be fuUy and unequivocally established, yet it does not foUow 
 that it was present in its free state, even when the liquid had a 
 strong acid reaction. For, it may have existed in the form of 
 one of the acid sulphates, such as common alum, the solutions 
 of which have an acid reaction; or it may have been present 
 as a neutral sulphate, svich as sulphate of magnesia, and the 
 acidity of the mixture have been due to the presence of some 
 other acid, as acetic acid in the form of vinegar ; or lastly, only 
 a portion of it may have been free, the mixture having contained 
 both the free acid and a sulphate. 
 
 To determine this point, k portion of the suspected solution 
 is evaporated to dryness, when, if it leave no sahne residue or 
 
SEPARATION FROM ORGANIC MIXTURES. 115 
 
 only an insignificant one, it is certain that the acid existed in 
 its free state; if, however, it leaves a saline deposit, then there 
 may have been no free sulphuric acid present. When the 
 original mixture contains much organic matter, it may be diffi- 
 cult at first, by simple inspection, to determine the presence or 
 otherwise of saline matter in the evaporated residue. When 
 this is the case, the residue should be moistened with pure nitric 
 acid and the mixture evaporated at a moderate heat to dryness, 
 and the operation repeated imtil the dry residue has a yellow 
 color, after which the heat is gradually increased till the organic 
 matter is entirely destroyed, when if a salt be present, it will 
 remain as a white mass. The nitric acid in this operation facil- 
 itates the decomposition of the organic matter, and at the same 
 time prevents the reduction of any sulphate present to the state 
 of sulphuret, which might otherwise take place during the 
 oxidation of the organic matter. If the ignited mixture thus 
 leaves a saliae residue, a portion or the whole of the sulphuric 
 acid may have existed in the form of a sulphate. A portion of 
 the residue may be dissolved in water and the solution tested in 
 the ordinary manner. It does not follow, however, from thus 
 obtaining a sulphate, for reasons pointed out hereafter, that even 
 any part of the acid originally existed in its combined state ; yet 
 under these circumstances, it can never be proved by chemical 
 means, that the whole of the acid was originally present in its 
 free state. 
 
 For determining and separating free sulphuric acid from 
 solutions of its salts, various methods have been advised. Thus, 
 it has been proposed to concentrate the mixture to near diyness 
 and agitate the residue with absolute alcohol or ether, for the 
 purpose of dissolving the free acid while its salts would remain 
 insoluble. But, as remarked by Dr. Christison, alcohol will 
 extract a portion of sulphuric acid from acid sulphates, and even 
 neutral sulphates are not wholly insoluble in this menstruum; 
 and again, ether extracts the free acid to only a very limited 
 extent, even in the presence of only a very minute quantity 
 of water. It has also Jbeen proposed, to add to the warmed 
 mixture, finely-powdered carbonate of baryta, in small quantity 
 at a time, as long as it produces effervescence, by which the 
 
116 SULPHURIC ACID. 
 
 free acid would be precipitated as sulphate of baryta, while 
 the soluble sulphate present would remain unacted upon. The 
 precipitate thus obtained would, therefore, represent the amount 
 of free acid present. By stopping the addition of the baryta 
 carbonate the moment effervescence ceases, this method under 
 certain conditions, yields very accurate results ; yet, if the sul- 
 phate present was a neutral alkaline salt, it would, partially at 
 least, be estimated as an acid sulphate, while on the other 
 hand, some of the acid sulphates, as common alum, decompose 
 carbonate of baryta with effervescence. Should, however, the 
 original mixture contain a sulphate and a free acid not sulphuric, 
 the operator might be wholly misled by this method. Thus if 
 the free acid existed in excess over the salt, the carbonate of 
 baryta would precipitate the whole of the sidphuric acid from 
 the salt, and still give rise to effervescence: under these circum- 
 stances, therefore, the whole of the precipitate would be due 
 simply to the presence of a sulphate. 
 
 When the examination has shown the presence of sulphuric 
 acid in a solution which contains a saline compound, the safest 
 and most accurate method for determining whether or not the 
 whole of the acid may have existed in the form of a sulphate, 
 is the following : A given volume of the solution, after the 
 addition of a httle hydrochloric acid, is treated with excess of 
 chloride of barium, and the precipitate collected, dried and 
 weighed, in the manner described hereafter; an equal volume 
 of the solution is then evaporated to dryness, the residue thor- 
 oughly dried, but not ignited, then dissolved in acidulated water, 
 the filtered solution precipitated as before, and the dried deposit 
 weighed. Every 2-38 parts by weight of the former precipitate 
 in excess over the latter, correspond to one part of free mono- 
 hydrated sulphuric acid. This estimate may however fall short 
 of the real amount of the free acid originally present, but it 
 could never exceed it. If in determining the amount of com- 
 bined acid in the evaporated residue, the latter be ignited, any 
 acid sulphate present might give up a portion of its acid, which 
 would, therefore, be estimated as free ; so also, the ignition might 
 reduce some of the sulphate to the state of sulphuret, and thus 
 cause an error in the same direction. If the suspected solution 
 
SEPARATION FROM ORGANIC MIXTURES. 117 
 
 contained simply a sulphate and a free acid other than sulphuric, 
 the precipitates obtained by both of the above operations, would, 
 of course, be equal in weight. 
 
 Although this method, as just intimated, may under certain 
 conditions, fail to show the whole of the acid as free that really 
 existed as such, yet in most instances, this would not be likely 
 to seriously affect the results. Nevertheless, cases might occur 
 in which the operator would be led to conclude that little or 
 even none of the acid was present in its free state, when the 
 whole of it had been added as such. Thus, for example, if free 
 sulphuric acid was added to a solution of chloride of sodimn, or 
 common salt, the mixture on evaporation would leave an acid 
 sulphate of soda, the chlorine, in part at least, of the common 
 salt being expelled in the form of hydrochloric acid. If under 
 these circumstances, the amount of salt present equaled or 
 exceeded the acid added, the whole of the latter would be 
 estimated as combined. Similar results would be observed in 
 regard to solutions of other salts. In a solution containing 
 one base and two different acids, especially in about equivalent 
 proportions, it is impossible by chemistry alone, to determine 
 which acid origmaUy existed in combination with the base. 
 Cases of this kind, it is true, are not hkely to occur in medico- 
 legal investigations, especially in the examination of suspected 
 articles of food or drink, yet it is well to bear in mind the 
 possibihty of their occurrence. In suspected solutions containing 
 this poison, the nature of the mixture and attending circum- 
 stances, usually leave no doubt as to its true character. 
 
 Contents of the Stomach. — These, carefully collected in a 
 large porcelain dish, are tested in regard to their chemical 
 reaction, any solids present cut into small pieces, and the 
 mixture, after the addition of water if necessary, kept at about 
 a boiling temperature for half an hour or longer; the cooled 
 mass is then strained, the solids washed with hot water, the 
 united liquids concentrated, filtered, and the filtrate examined 
 in the manner pointed out above. This method would of course 
 be equally applicable for the examination of the matters ejected 
 from the stomach by vomiting during life. Should an antidote, 
 such as an alkaline carbonate, have been administered, the 
 
118 SULPHURIC ACID. 
 
 contents of the stomach, as well as the matters vomited, may 
 contain the acid only in the form of a sulphate and have a 
 neutral reaction. Under these circumstances, in the prepara- 
 tion of the mixture, it should be strongly acidulated with 
 hydrochloric acid; the amount of combined sulphuric acid is 
 then estimated in the manner already described. 
 
 So also, if the person had been actively treated or survived 
 the taking of the poison some days, it may have entirely disap- 
 peared from the stomach. This result has been observed in 
 several instances in which death took place within even short 
 periods. Thus in a case mentioned by Mertzdorff, in which the 
 poison proved fatal within twelve hours to a child, the contents 
 of the stomach had no acid reaction, but on the contrary an 
 ammoniacal odor, and contained a soluble sulphate, probably the 
 sulphate of ammonia. (Christison On Poisons, p. 126.) This 
 conversion, according to Orfila, always takes place with greater 
 or less rapidity, when the acid is present in decomposing nitro- 
 genised organic mixtures. 
 
 It is well known that the natural secretions of the stomach 
 have usually a distinctly acid reaction, due to the presence of 
 minute quantities of hydrochloric and lactic acids. Whether 
 the acidity of the mixture under examination is due simply to 
 these acids or really to the presence of free sulphuric acid, can, 
 of course, only be determined by the attending circumstances 
 and a chemical analysis. In determining the quantity of free 
 sulphuric acid present, it must be borne in mind that the con- 
 tents of the stomach usually contain small quantities of alkaline 
 salts, particularly chlorides, and that these, on evaporating the 
 mixture to dryness, will convert a corresponding portion of the 
 free acid into sulphates : the proportion thus converted, however, 
 would rarely affect the general results. In this connection it 
 must also be remembered that sulphates may be normally present 
 in very minute quantity in articles of food and complex organic 
 mixtures ; and moreover, that some of these salts are used 
 medicinally in large doses. 
 
 From the above considerations, it is evident that in poisoning 
 by sulphuric acid, cases may readily arise in which the proof 
 of the poisoning will rest chiefly or entirely upon the symptoms 
 
QUANTITATIVE ANALYSIS. 119 
 
 and post-mortem appearances. In all such cases, however, Ve 
 should be able to satisfactorily account for the failure of the 
 chemical analysis. 
 
 From organic fabrics. — The texture of articles of clothing 
 with which sulphuric acid comes in contact is usually more or 
 less destroyed, and the spots remain moist for a long period, due 
 to the affinity of the acid for water ; so also, the color of the 
 article is more or less changed, it in most instances assuming a 
 reddish or brownish hue. These spots may retain an acid reac- 
 tion for many months or even years. 
 
 The presence of the acid in stains of this kind may be 
 determined by boiling the stained portion with a small quantity 
 of pure water, filtering the solution thus obtained, and examin- 
 ing the filtrate in regard to its chemical reaction and with 
 chloride of barium, in the usual manner. A portion of the fil- 
 trate should also be examined in regard to the presence of 
 saline matter. Should the latter be present with the acid, it 
 then becomes necessary to determine, in the manner already 
 indicated, whether or not the whole of the acid may have been 
 in its combined state. If the examination shows that this may 
 have been the case, it is then necessary to examine an equal 
 portion of the unstained article, after the same process, since in 
 the preparation of fabrics of this kind minute quantities of sul- 
 phates are sometimes employed. 
 
 Quantitative Analysis. — Sulphuric acid is usually esti- 
 mated ia the form of sulphate of baryta. For this purpose, the 
 solution is treated with sKght excess of chloride of barium, and 
 the mixture gently heated until the baryta precipitate has com- 
 pletely subsided. The deposit is then collected on a small filter 
 of known ash, repeatedly washed with hot water containing 
 hydrochloric acid, dried, ignited, and weighed. When only a 
 small quantity of the precipitate is present, after being washed 
 and dried it should as far as practicable be removed from the 
 filter, and ignited alone ; the filter with any adherent sulphate is 
 then ignited, and the weight of the residue, after deducting the 
 ash of the filter, added to the weight of the previoiisly ignited 
 sulphate. 
 
120 NITRIC ACID. 
 
 Every one hundred parts by weight of sulphate of baryta 
 thus obtained, correspond to 42-02 parts of monohydrated sul- 
 phuric acid, 105 grains of which measure one fluid drachm. 
 
 Section II. — Nitric Acid. 
 
 Nitric Acid, or aqua fortis, as found in the shops, is a 
 powerfully corrosive acid liquid, having usually a more or less 
 yellow or even reddish color. In its action upon organic sub- 
 stances, it is about equally active with sulphuric acid. Instances 
 of poisoning by it, however, have been of very much less fre- 
 quent occurrence than by the latter. 
 
 Symptoms. — These in most respects are identical in kind 
 with those observed in sulphuric acid poisoning. When the 
 acid is swallowed in its concentrated state, the mucous mem- 
 brane of the mouth and other parts with which the liquid comes 
 in contact, is immediately corroded and assumes a white appear- 
 ance, which, however, unlike that produced by sulphuric acid, 
 soon changes to yellow, and then in some instances slowly 
 becomes more or less brown. All spots produced on the ex- 
 ternal skin by the acid, very soon acquire, a permanent yellow 
 color. 
 
 The usual symptoms are violent pain in the mouth, oesoph- 
 agus, and stomach ; copious eructations of gaseous matter, hav- 
 ing sometimes a reddish color, due to the presence of the 
 decomposed acid; excessive vomiting of strongly acid, yellow 
 or brownish matters ; tenderness and tension of the abdomen ; 
 general coldness of the body, especially in the extremities ; 
 difificulty of respiration and of deglutition, from the local action 
 of the acid on the internal organs of the mouth and fauces ; a 
 small and frequent pulse ; extreme thirst, cold sweats, and great 
 prostration of strength. The local action of the acid may be 
 confined to the mouth and fauces, none of the poison having 
 been swallowed. 
 
 In most instances, the more immediate symptoms produced 
 by nitric acid are proportionate to the degree of its concentra- 
 tion and the quantity taken; but this is by no means always 
 
PHYSIOLOGICAL EFFECTS. 121 
 
 the case. Thus Dr. Beck cites the case of a young man, who 
 died in twenty hours, from the effects of the acid, without at 
 any time showing signs of acute pain or of agitation ; yet after 
 death, there was found perforation of the stomach, with great 
 effusion of its contents into the abdomen. In another case, a 
 woman swallowed a quantity of the poison, and, at least for 
 some hours afterwards, there was neither agitation, pain nor 
 vomiting, but a condition rather indicating typhus fever. She 
 died the following day, and on examination of the body, there 
 was found most extensive disorganisation of the abdominal 
 organs : perforation of the stomach, gangrenous spots, effusion 
 iato the abdomen, marked erosion, and a general yellow color 
 of all the viscera. 
 
 If the patient survive the primary effects of the poison, 
 these may be succeeded by irregular fever, obscure pains in 
 the throat and epigastric region, impaired digestion, irritability 
 of the stomach, frequent vomiting, obstinate constipation, dry- 
 ness of the skin, disturbed respiration and deglutition, some- 
 times profuse sahvation, fetid breath, frequent rigors, and great 
 muscular emaciation. Sometimes large membranous flakes or 
 even masses of the lining membrane of the throat and oesoph- 
 agus are ejected with the vomited matters. 
 
 The vapor, or fumes, arising from nitric acid, has in several 
 instances caused death. .In a recent instance of this kind, a 
 chemist, Mr. Stewart, of Edinburgh, and his assistant, inhaled 
 the fumes whde endeavoring to save a portion of the liquid that 
 had escaped from a broken jar. After an hour or two, the 
 former began to experience difficulty of breathing, and sent for 
 medical advice, but he very rapidly became worse, and died 
 iu about ten hours after the accident. His assistant was also ' 
 taken ill, and died about fifteen hours later. (Chem. News, Lon- 
 don, March, 1863, p. 132.) An instance is also reported by Mr. 
 Spence, in which the fumes of the acid proved fatal to two 
 persons ; the first of whom died in about forty hours, and the 
 other some hours afterwards. (Ibid, p. 167.) In at least one of 
 these cases, the symptoms were delayed for some hours. In the 
 well-known case of Mr. Haywood, who inhaled the fumes arising 
 from a mixture of nitric and sulphuric acids, the symptoms were 
 
122 NITRIC ACID. 
 
 delayed for more than three hours, and death occurred in about 
 eleven hours. 
 
 Period when Fatal. — Nitric acid has in several instances 
 caused death within a very few hours, and in most instances in 
 which death occurred from its primary effects, that event fol- 
 lowed within forty-eight hours; but the patient may recover 
 from the primary action of the poison and die from secondary 
 effects many months afterwards. Thus in a case quoted by Dr. 
 Taylor, death occurred in one hour and three-quarters after the 
 poison had been swallowed; while, on the other hand, Tartra 
 mentions an instance in which death did not occur until after a 
 period of eight months. Out of fifty-six cases of poisoning by 
 nitric acid, collected by Tartra, twenty-one of the patients 
 completely recovered, and eight partially. 
 
 Fatal Quantity. — In most of the instances of poisoning by 
 this substance, the quantity taken was not ascertained. Most 
 writers on this subject, however, agree in fixing the fatal quan- 
 tity, for a healthy adult under ordinary conditions, at about two 
 drachms of the concentrated acid; yet quantities much larger 
 than this have in several instances been followed by complete 
 recovery. In a case reported by Dr. J. M. Warren, a woman, 
 aged thirty-four years, having with suicidal intent taken three 
 drachms of the acid into her mouth swallowed a portion, but 
 most of it was spit out. She was seized with the usual symp- 
 toms, which, however, after several days, under active treat- 
 ment, nearly subsided; but secondary symptoms set in and she 
 died on the fourteenth day after the poison had been taken 
 (Amer. Jour. Med. Sci., July, 1850, p. 36). 
 
 Treatment. — This consists in the speedy administration of 
 calcined magnesia, chalk, or a dilute solution of an alkaline 
 carbonate, followed by the free exhibition of oily or mucilagin- 
 ous drinks. In every respect, the treatment is the same as that 
 already mentioned in sulphuric acid poisoning {ante, p. 101). 
 
 Post-mortem Appearances. — These wUl, of course, depend 
 somewhat on the length of time the individual survived after 
 taking the poison. In acute cases, the lining membrane of 
 the lips, mouth and fauces, has sometimes a white, but more 
 generally a deep yellow or even brownish color; often large 
 
PATHOLOGICAL EFFECTS. 123 
 
 patches of this membrane are entirely removed. The mucous 
 membrane of the oesophagus is often much thickened and altered 
 in structure, of a yellow color, and readily separated. And 
 like appearances may be observed in the larynx and trachea, 
 if the acid has passed into these organs. In these examin- 
 ations, as in sulphuric acid poisoning, it must be borne in 
 mind that the mouth and oesophagus may exhibit but little 
 injury, the stomach being the part chiefly afi"ected ; and on the 
 other hand, that the whole of the local injury may be confined 
 to the mouth and air-passages, little or none of the poison hav- 
 ing been swallowed. In an instance of poisoning by this acid 
 quoted by Dr. Christison, it left no trace of its passage down- 
 ward until it had arrived near the pylorus. 
 
 The stomach is usually distended, externally changed in 
 color, more or less inflamed, and adherent to the neighboring 
 organs. The contents of this organ have frequently a yellow 
 color, due to the action of the acid upon the contained matters. 
 The mucous membrane is often greatly disorganised and much 
 changed in color, and the blood-vessels injected with dark coag- 
 ulated blood. In the case reported by Dr. Warren, the stomach 
 externally was of a purple color, and adherent to the neighbor- 
 ing parts ; internally it was of a greenish-yellow color, and its 
 tissues were so softened that it could not be separated from the 
 surrounding parts without being greatly lacerated. When the 
 coats of the stomach are perforated by the acid, which how- 
 ever rarely happens, the contents of the organ may escape into 
 the abdomen and cause a yeUow coloration and great disorgan- 
 isation of all the neighboring viscera. 
 
 The small intestines, particularly the upper portion, may 
 exhibit appearances similar to those found in the stomach; 
 often, however, they entirely escape the direct action of the 
 acid, it not passing below the stomach. The large intestines 
 are usually fiUed with hard faeces. The other abdominal organs 
 are often more or less highly inflamed, even when the stomach 
 is not perforated; the bladder is usually empty, no urine hav- 
 ing been secreted. 
 
 When the patient survives the primary efi"ects of the poison 
 and dies from secondary results, the body is greatly emaciated. 
 
124 NITRIC ACID. 
 
 and the stomach and other portions of the alimentary canal 
 more or less contracted, their walls thickened and the cavities 
 nearly closed. Stricture of the cBsophagus has not unfrequently 
 occurred, and the pyloric end of the stomach has been so 
 greatly contracted as to nearly obliterate its opening. In some 
 few instances, the stomach was so far destroyed that no part of 
 its structure could be distinguished. 
 
 Chemical Peopeeties. 
 
 Geneeal Chemical Natuee. — Anhydrous nitric acid is a 
 compound of the elements Nitrogen and Oxygen, in the pro- 
 portion of one equivalent of the former to five of the latter 
 (NO5). It is a very rare, transparent, colorless, crystalline 
 substance ; in this state it melts at 85°, and boils at about 
 113° F. : it was first obtained, in 1849, by Deville. In com- 
 bination with water, it has long been known under the name of 
 aqua fortis, which in its most concentrated form, consists of 
 one equivalent of the anhydrous acid in combination with one 
 of water (HO, NOg.) 
 
 In its pure hydrated state, nitric acid is a colorless, intensely 
 corrosive acid liquid, which in its most concentrated form, has a 
 density of about 1-520, and contains 85-72 per cent, of the an- 
 hydrous acid. The density of the acid of the shops, usually 
 varies from 1"350 to 1'450. Concentrated nitric acid is one of 
 the most powerfully corrosive substances known. It imparts a 
 yellow stain to the skin, nails, wool and ■ other organic sub- 
 stances. Exposed to the air, it emits white fumes ; when 
 mixed with water, it evolves a sensible amount of heat. It 
 boUs at about 184°, and freezes at — 40° F. When the con- 
 centrated acid is boiled, it diminishes in density and its boiling 
 point increases, until the liquid acquires a density of 1'424, 
 when it distills unchanged in the form of a definite hydrate of 
 the acid, consisting of four equivalents of water with one equiv- 
 alent of real acid (4 HO; NO5). 
 
 The following table, according to Dr. Ure, indicates approx- 
 imatively the per cent, by weight, of anhydrous nitric acid 
 (NO5) in pure aqueous solutions of difi"erent specific gravities : 
 
SPECIAL CHEMICAL PROPERTIES. 
 
 125 
 
 STRENGTH OF AqUEOUS SOLUTIONS OF NITRIC ACID. 
 
 SP. GE. 
 
 PER CKNT. 
 
 SP. GR. 
 
 PER CENT. 
 
 8P. OR. 
 
 PEE CENT. 
 
 BP. G&. 
 
 PER CENT. 
 
 1-500 
 
 79.7 
 
 1-402 
 
 56-6 
 
 1-258 
 
 35-1 
 
 1-117 
 
 16-7 
 
 1-491 
 
 76-5 
 
 1-383 
 
 53-4 
 
 1-246 
 
 33-5 
 
 1-093 
 
 13-5 
 
 1-479 
 
 73-3 
 
 1-363 
 
 50-2 
 
 1-221 
 
 30-3 
 
 1-071 
 
 10-4 
 
 1-467 
 
 70-1 
 
 1-343 
 
 47-0 
 
 1-196 
 
 27-1 
 
 1-048 
 
 7-2 
 
 1-453 
 
 66-9 
 
 1-322 
 
 43-8 
 
 1-183 
 
 25-5 
 
 1-027 
 
 4-0 
 
 1-439 
 
 63-8 
 
 1-300 
 
 40-4 
 
 1-171 
 
 23.9 
 
 1-016 
 
 2-4 
 
 1-419 
 
 69-8 
 
 1-283 
 
 38-3 
 
 1-146 
 
 20-7 
 
 1.005 
 
 0-8 
 
 Nitric acid as found in commerce, is generally more or less 
 colored, the color being due to the presence of some of the 
 lower oxides of nitrogen, and varying from a light yellow to an 
 orange red. In this state, it is even more corrosive than the 
 pure acid. It is not unfrequently contaminated with sulphuric 
 and hydrochloric acids, and other impurities. 
 
 The salts of nitric acid are for the most part colorless, and 
 very freely soluble in water. They are all decomposed by a 
 red heat. Their aqueous solutions are also decomposed when 
 heated with free sulphuric acid, with the formation of a sul- 
 phate, the nitric acid being eliminated in its free state. 
 
 Special Chemical Properties. — Nitric acid very readily 
 parts with a portion of its oxygen. When brought in contact 
 with many of the metals, such as copper, zinc, iron or tin, it is 
 in part decomposed with great rapidity, with the formation of a 
 nitrate and the ^evolution of one or more of the lower oxides of 
 nitrogen in the form of deep red fumes. The evolution of these 
 firmes is quite characteristic of the acid. 
 
 When a nitrate, in its dry state, is brought in contact with 
 ignited charcoal, the latter bums vividly at the expense of the 
 oxygen of the nitric acid, the salt, if an alkaline compound, 
 being converted into a carbonate. 
 
 On account of the free solubility of the compounds of nitric 
 acid, it can not be precipitated from solution by reagents; 
 however, the presence of very minute traces of the acid^ can 
 be detected with great certainty. When not too much diluted, 
 it may be recognised by the properties already mentioned. In 
 the following examination of the behavior of solutions of nitric 
 
126 NITRIC ACID. 
 
 acid, the fractions employed express the fractional part of a 
 grain of the anhydrous acid present in one grain of the solution, 
 the menstruum being pure water. 
 
 1. Copper Test. 
 
 When tolerably strong nitric acid is treated in a test-tube 
 with a slip of copper-foil, the acid in part is immediately 
 decomposed with the evolution of binoxide of nitrogen, which 
 in coming in contact with the air is oxidised and escapes in 
 the form of deep red fumes of hyponitric acid (NO4); at the 
 same time, the undecomposed portion of the acid unites with 
 the oxide of copper formed to nitrate of copper, which imparts 
 to the liquid a more or less greenish color. These reactions 
 are expressed by the following formulae : 4 NO5 + 3 Cu = 3 CuO, 
 NO5+NO2; then,N02+02 = N04. 
 
 When the acid is more dilute, it is not acted upon by 
 copper unless the mixture be heated or free sulphuric acid be 
 added, and the gas evolved may be colorless; its presence, 
 however, may be recognised by its peculiar odor, acid reaction, 
 and by rendering blue a piece of starch-paper moistened with 
 a solution of iodide of potassium. In the presence of sulphuric 
 acid, the whole of the nitric acid, whether in its free state or 
 as a nitrate, is evolved finally in the form of hyponitric acid. 
 
 The following results refer to the behavior of Jive grains of 
 the nitric acid solution with a very small slip of copper-foil. 
 
 1. 10th solution, or half a grain of anhydrous nitric acid in five 
 
 grains of water, fails to be acted upon by the copper 
 till heat is applied, — then decomposition takes place quite 
 briskly, yielding quite perceptible red vapors, which 
 quickly redden moistened litmus-paper, and impart a blue 
 color to starch-paper prepared as above. The liquid 
 assumes a very marked greenish-blue color, 
 
 2. 20th solution, yields only a feeble reaction, even on the 
 
 .application of heat; but if a few drops of concentrated 
 sulphuric acid be added, there is a brisk reaction and 
 ultimately the liquid acquires a very distinct greenish- 
 blue color. 
 
GOLD TEST. 127 
 
 3. 50th solution, gives no evidence of decomposition by heat 
 
 alone ; but with sulphuric acid and heat, it yields a brisk 
 reaction and a light greenish-blue solution. If this experi- 
 ment be performed in a very narrow tube, the evolved 
 gas imparts a distinct reddish hue to the contained air. 
 
 4. 100th solution, under the influence of a few drops of sul- 
 
 phuric acid and heat, yields a quite good effervescence 
 aroimd the surface of the copper, and the liquid acquires 
 a faint greenish-blue color. 
 
 5. 500th solution, under the same influences as 4, yields a 
 
 very distinct effervescence, and after a time the fluid 
 acquires a perceptible greenish tint. 
 
 6. 1,000th solution, yields a perceptible reaction. 
 
 Eesults similar to the above may be obtained from the acid 
 when in the form of a nitrate; but then, the addition of sul- 
 phuric acid is necessary in all cases. If the nitrate to be 
 tested is in the solid state, it should be dissolved in the least 
 practicable quantity of water ; on the other hand, if it is in 
 solution, the liquid should be concentrated as far as practicable 
 before the test is appKed. In the use of this test, it must be 
 kept in mind that sulphuric acid not unfrequently contains 
 traces of nitric acid: the presence of this impurity could, of 
 course, be determined by the test itself, before it is apphed to 
 a suspected solution. 
 
 2. Gold Test. 
 
 If a solution of free nitric acid or of a nitrate, be heated 
 with excess of pure hydrochloric acid, the two acids react upon 
 each other and eliminate free chlorine, which has the property 
 of dissolving gold-leaf to the form of chloride of gold. The 
 presence of the gold compound can be recognised, when present 
 in not too minute quantity, by a solution of chloride of tin, 
 which produces a purple precipitate, or at least imparts a 
 purplish color to the liquid. 
 
 Before applying this test to a suspected solution, the hydro- 
 chloric acid about to be employed should be tested alone, in 
 order to determine whether it is entirely free from uncombined 
 chlorine, which is often present. 
 
128 NITRIC ACID. 
 
 When one grain of the nitric acid solution is mixed, in a 
 small test-tube, with five grains of tolerably strong hydrochloric 
 acid and a very small slip of gold-leaf, the mixture on being 
 heated to the boiling temperature, yields the following results : — 
 
 1. xw grain of nitric acid: in a very little time, the gold 
 
 dissolves ; the cooled solution yields "with the tin reagent 
 no immediate change, but after a little time, it assumes a 
 decided purple color. 
 
 2. i.Joo grain : after a little time the gold dissolves, and the 
 
 cooled solution yields with the tin compound a faint purple 
 color. 
 
 3. 5,0^0 grain, after several minutes, dissolves a very minute 
 
 quantity of gold; but the solution fails to yield satisfactory 
 
 results with the tin reagent. 
 These reactions are also common to solutions of chlorates, 
 hypochlorites, chromates, iodates, and bromates. The same is 
 also true of the sesqui-combinations of iron, as first pointed out 
 by Henry Wurtz (Chem. Gazette, xvii, p. 32). This metal is 
 readily separated by treating • the solution with carbonate of 
 soda, and filtration. It need hardly be added that a nitrate 
 may be distinguished from all of these fallacious salts, by the 
 action of the preceding test. 
 
 3. Iron Test. 
 
 When free nitric acid or a solution of a nitrate, is mixed 
 with several times its volume of concentrated sulphuric acid 
 and the cooled mixture treated with a crystal of sulphate of 
 iron, the latter after a time becomes surrounded by a blackish- 
 brown, brownish or purple compound, which is said to consist 
 of 4 FeO, SO3 ; NO2. Instead of using the iron salt in its solid 
 state, it is more satisfactory to employ it in the form of a 
 saturated solution. To thus apply the test, a drop of the nitric 
 acid solution is thoroughly rnixed in a small test-tube with 
 eight or ten times its volume of sulphuric acid, the mixture 
 gently warmed for a little time, then cooled by immersing the 
 tube in cold water ; a drop of the iron solution is then allowed 
 to flow down the inside of the tube upon the acid mixture. 
 
INDIGO TEST. 129 
 
 when the stratum where the two liquids are in contact will 
 acquire a beautiful purple or brownish-purple color, the tint 
 depending, on the quantity of nitric acid present ; on now 
 slowly mixing the liquids by means of a glass rod, taking 
 great care that no heat is evolved, the same coloration will be 
 observed throughout the mixture. 
 
 !• ToT grain of nitric acid, in one grain of water, when treated 
 as above, the contact surfaces of the iron and acid liquids 
 present a beautiful purple line ; on carefully mixing the 
 liquids, the mixture assumes a deep purple color, and soon 
 begins to effervesce, gives out the odor of hyponitric acid, 
 and the color becomes discharged. On the addition of 
 another drop of the iron solution, the color is reproduced. 
 
 2. 1,0^0 grain, yields a beautiful purple mixture, which remains 
 
 unchahged for at least several hours. 
 
 3. 5,0^0 " grain: on mixing the two solutions, they assume a 
 
 very decided purplish tint, which is permanent for some 
 
 hours, 
 ■i- 10.000 grain: the mixed liquids assume a distinct purplish 
 
 hue, which after some hours becomes pinkish. These 
 
 colors are best seen by inclining the tube over a piece of 
 
 white paper. 
 Much the same results as those just described, may be 
 obtained by employing the iron compound in the solid state ; its 
 solution, however, is preferable. In all cases, before applying 
 this test to a suspected solution, the sulphuric acid should be 
 tested alone : in fact, it is somewhat difficult to find that acid 
 in the shops entirely free from traces of nitric acid or some of 
 the lower oxides of nitrogen. 
 
 4. Indigo Test. 
 
 When a solution of nitric acid or of a nitrate, is mixed 
 with hydrochloric acid, or chloride of sodium as recommended 
 by Liebig, and the mixture colored by a solution of indigo, 
 then heated with sulphuric acid, the chlorine set free through 
 the agency of the nitric acid, will discharge the blue color of 
 the mixture. In applying this test, a small quantity of the 
 
130 NITRIC ACID. 
 
 nitric acid solution is treated with a few crystals of pure 
 common salt or a drop of hydrochloric acid and just enough 
 of a strong sulphuric acid solution of indigo to impart a distinct 
 blue tint; the mixture is then heated, and while hot a few 
 drops of concentrated sulphuric acid cautiously added and mixed 
 with the liquid, after which, if necessary, the heat is continued 
 until the blue tint of the fluid disappears. 
 
 The following results refer to the behavior of five grains of 
 the nitric acid solution. 
 
 1. 100th solution, when treated as above, the blue color, on the 
 
 addition of a few drops of sulphuric acid to the heated 
 mixture, is immediately discharged and the liquid assumes 
 a yellow color. 
 
 2. 1,000th solution, yields much the same results as 1. 
 
 3. 10,000th solution : the blue color is not discharged until the 
 
 mixture is heated some minutes with several drops of sul- 
 phuric acid ; the liquid then acquires a faint yellow tint. 
 
 4. 20,000th solution, behaves much the same as 3. 
 
 5. 50,000th solution, requires to be boiled several minutes with 
 
 several drops of sulphuric acid, before the blue tint dis- 
 appears. For the success of this reaction, it is necessary 
 to employ the merest trace of indigo, the tiut of which is 
 best seen by incUning the tube containing the mixture, 
 over white paper. 
 It is well known that chlorates, chromates, iodates, binoxide 
 of manganese, and several other similar compounds, have, like 
 nitric acid, the property of evolving chlorine from hydrochloric 
 acid, and therefore of bleaching a solution of indigo ; and 
 Wurtz, in his valuable paper already referred to, has shown 
 that the chlorides of gold, platinum and tin, bleach an indigo 
 solution, even without the presence of hydrochloric acid, and 
 that in the presence of this acid, arsenic acid has a similar 
 property. It is not likely, however, that either of these falla- 
 cious substances would be present in a medico-legal investiga- 
 tion for nitric acid. 
 
 Much more probable sources of error than either of those 
 just mentioned, to be guarded against, are the presence of free 
 chlorine in the hydrochloric acid, and of traces of nitric acid 
 
BRUCINE TEST. 131 
 
 or some of the lower oxides of nitrogen, in the sulphuric acid 
 employed. No reliance whatever could be placed in this test 
 when applied to organic mixtures. 
 
 5. Brucine Test. 
 
 This test, which was first suggested by Berthemont, is based 
 on the production of a blood-red color, when nitric acid or a 
 nitrate is mixed with a sulphuric acid solution of brucine. Pure 
 brucine, when added to pm'e sulphuric acid, assumes a pale 
 piak color and slowly dissolves to a colorless or nearly colorless 
 solution, unless the proportion of alkaloid be comparatively 
 large, when the solution has a pinkish hue. 
 
 When one grain of the free nitric acid solution or of a 
 
 nitrate is mixed, for convenience in a white porcelain dish, 
 
 with about Jive fluid grains of concentrated sulphuric acid, and 
 
 a few crystals of brucine added, if the solution contains : — 
 
 !• To~o grain of anhydrous nitric acid, the brucine immediately 
 
 assumes a red-orange color, and on being stirred, dissolves 
 
 to a solution of the same hue, which very slowly fades to 
 
 bright yellow. 
 
 2. i.Joo grain : the alkaloid acquires a red color, and yields a 
 
 dull orange solution, which slowly becomes yellow. 
 
 3. -5,0 grain : the brucine assumes a rose pink color, and 
 
 dissolves to a solution having a decided reddish-pink hue, 
 which changes to faint orange, then fades to yellow. 
 
 4. 1 0,000 grain : the crystals acquire a pink color and dissolve 
 
 to a solution of the same tint, which becoming amber 
 changes to yellow. 
 
 5- 2 5,0 grain : the bruciae assumes a reddish color, and when 
 stirred in the mixture, imparts to it a decided amber color, 
 which soon changes to light yellow. 
 
 6. 5 0,000 grain : the alkaloid becomes slightly colored, and 
 yields a solution of a faint amber color, which quickly 
 changes to very light yellow. These colors are quite 
 feeble, yet when the reaction is compared with that 
 obtained from the alkaloid and sulphuric acid alone, the 
 difference is very well marked. 
 
132 NITRIC ACID. 
 
 When the nitric acid is in the solid state in the form of a 
 nitrate, the reaction of this test is even more delicate than 
 when applied to solutions. Under these circumstances, a very 
 small portion of the salt, or the residue left on evaporating its 
 solution to dryness, is dissolved ia a few drops of sulphuric 
 acid, and then a crystal or two of the alkaloid added. The 
 residue obtained from a solution of nitrate of potash containing 
 only the 100,000th part of a grain of nitric acid, when moist- 
 ened with a very small drop of sulphuric acid containing a little 
 brucine, immediately assumes a distinct orange color, and dis- 
 solves to a brick-dust pink solution, the tint of which soon 
 fades to faint yellow. 
 
 This test furnishes the most ready and delicate means of 
 determining the purity of sulphuric acid in regard to the pres- 
 ence of traces of nitric acid. 
 
 A sulphuric acid solution of bruciae also produces a some- 
 what similar coloration with chloric acid and its' salts. But, the 
 most minute quantity of a salt of this kind, imparts a strong 
 yellow, and a very small quantity an orange color, to sulphuric 
 acid alone, and evolves fumes of hypochloric acid, having a 
 greenish color and peculiar odor. To guard against this fallacy, 
 therefore, it is only necessary to observe the action of the sul- 
 phuric acid alone. 
 
 6. Narcotine. 
 
 When a small quantity of narcotine is added to a few drops 
 of pure concentrated sulphuric acid, the alkaloid dissolves to a 
 light-yeUow solution, which when heated assumes a purplish 
 color ; but if free nitric acid or a nitrate be present, the narco- 
 tine dissolves to a reddish-brown solution, which on the appli- 
 cation of a gentle heat acquires a deep blood-red color. Mialhe 
 was the first to employ this reaction as a test for nitric acid. 
 
 When one grain of the nitric acid solution is mixed with 
 five fluid grains of sulphuric acid, and the mixture allowed to 
 cool, the addition of a few crystals of narcotine produces the 
 following results : — 
 
 1. xw grain of nitric acid: the alkaloid assumes a deep-brown 
 color, and imparts to the liquid a decided brownish-yellow 
 
IODINE AND OTHER TESTS. 133 
 
 color, which by heat is changed to a permanent deep 
 blood-red. ' 
 
 2. rroVo grain: the narcotine dissolves to a decided reddish 
 
 solution, which when heated assumes, a fine blood-red 
 color. 
 
 3. 5,0^0 grain, yields a distinct reddish color, which is changed 
 
 to reddish-brown by heat. 
 
 4. 10,000 grain : the solution of the alkaloid has a faint red- 
 
 dish tint, which by heat is changed to a purple-red. This 
 last color might be readily confounded with that from nar- 
 cotine alone ; but this alkaloid singly would not impart the 
 primary reddish tint. 
 When the nitric acid is in solution in the form of a nitrate, 
 the liquid should be evaporated, and the dry residue dissolved 
 in a few drops of colorless sulphuric acid, then tested by a few 
 crystals of narcotine. Under these conditions, given quantities 
 of the acid yield even stronger colors than described above. 
 
 Iodine Test. — This method, first proposed by J. Higgin 
 (Chem. Gaz., viii, p. 249), takes advantage of the property 
 possessed by nitric acid of decomposing hydriodic acid with the 
 evolution of free iodine, and the ready detection of the latter 
 by means of starch. To apply this test, the suspected solution 
 is mixed with about one-sixth of its volume of concentrate 
 sulphuric acid and heated to near the boiling temperature for 
 several minutes, then allowed to cool; the mixture is then 
 treated with a drop of starch mucilage and a few drops of a 
 very dilute solution of iodide of potassium, when, if nitric acid 
 is present, the liquid acquires a more or less blue color. The 
 author of this method states that a 20,000th solution of the 
 acid yields in a few minutes, a decided blue coloration. It 
 must be remembered, however, that sulphuric acid alone, will 
 after a time, liberate iodine, even from very dilute solutions of 
 iodide of potassium. 
 
 Othee Tests. — Mr. J. C. Schaeffer has suggested a test, 
 which depends on the conversion of nitric acid into nitrous 
 acid by the action of metallic lead, and the production of 
 a rich yellow color when the liquid is treated with yellow 
 
134 NITRIC ACID. 
 
 prussiate of potash and acetic acid (Chem. Gaz., ix, p. 289). 
 In somewhat strong solutions of the acid, this reaction is well 
 marked; but as the reagent alone yields a yellow coloration, it is 
 not applicable for the detection of the acid when much diluted. 
 Mr. J. Horsley has proposed a test,, which is applied as 
 follows : A small quantity of water, acidulated with a few drops 
 of sulphuric acid, is placed in a small test-tube, and a small 
 portion of pyrogalUc acid added, after which a little concen- 
 trated sulphuric acid is allowed to flow down the inside of the 
 tube and subside to the bottom of the mixture; a few crystals 
 of chloride of sodium are then added, and after the efferves- 
 cence has ceased, a small quantity of the solid nitrate to be 
 examined dropped into the mixture, when the subsided acid, in 
 a very Kttle time, assimies an intense purple or deep orange- 
 brown color, which may ultimately extend throughout the entire 
 mixture (London Chem. News, June, 1863, p. 268). We can 
 confirm the statement of Mr. Horsley in regard to the extreme 
 delicacy of this reaction, the smallest particle of a nitrate 
 yielding a very satisfactory coloration. 
 
 Separation from Organic Mixtures. 
 
 Suspected Solutions. — If the suspected liquid has a strong 
 acid reaction and is free from suspended solid matters, even 
 though it is somewhat colored, a portion of it may be examined 
 at once, by being placed in a small test-tube with a slip of 
 copper, when if the fluid contains one-third or more of its vol- 
 ume of the ordinary nitric acid of the shops, it will immediately 
 be acted upon by the metal, give off red fumes and yield a 
 greenish-blue solution. If this reaction fail, the mixture, after 
 the addition of sulphuric acid if necessary, is gradually heated, 
 and any evolved gas examined in regard to its color, odor, and 
 with wet litmus-paper and starch-paper moistened with a solu- 
 tion of iodide of potassium, in the manner already directed. 
 A very good method of applying this test, when the quantity 
 of liquid is limited, is to warm a few drops of the suspected 
 solution with several drops of sulphuric acid and a slip of cop- 
 per, in a watch-glass covered by an inverted glass containing 
 
SEPARATION FROM ORGANIC MIXTURES. 135 
 
 separate slips of the moistened litmus and starch papers. In 
 applying this method, it must be remembered that when a sul- 
 phuric acid solution of a chloride is heated, it will evolve 
 hydrochloric acid gas, which also reddens litmus-paper; and if 
 any oxidising substance is present, a portion of the evolved acid 
 may undergo decomposition with the elimination of free chlo- 
 rine, which wiU blue moistened iodised starch-paper. If there 
 be any uncertainty in regard to the true nature of these results, 
 a portion of the original solution is treated with a saturated 
 solution of acetate of silver, when, if a chloride is present, it 
 will yield a white precipitate of chloride of silver. If a pre- 
 cipitate be thus obtained, the solution is treated with slight 
 excess of the silver reagent, filtered, and then examined by the 
 copper test. Should the liquid under examination be free, or 
 nearly so, from organic matter, some of the other tests for the 
 acid may be applied. 
 
 When these examinations show the presence of nitric acid, 
 it may become necessary to prove that it was not in the form 
 of a nitrate and the acidity of the solution due to the presence 
 of some other acid. For this purpose, a portion of the solution 
 is evaporated to dryness, when if it leave no saline residue it 
 follows that the acid existed in its free state. If however it 
 leave a saline residue, the examination must be conducted on 
 the same principles as pointed out for the determination of sul- 
 phuric acid under like circumstances (ante, p. 116). 
 
 Should the suspected solution be mixed with solid organic 
 matters, the mixture, after the addition of pure water if neces- 
 sary, is gently boiled for about twenty minutes, allowed to cool, 
 filtered, the solids on the filter washed, and the concentrated 
 filtrate tested. In thus preparing an organic mixture contain- 
 ing free nitric acid, it is well to bear in mind that a porticAi of 
 the acid may undergo decomposition : for this reason, it is some- 
 times best to neutralise the acid by an alkali, before subjecting ' 
 the mixture to the action of heat. When the prepared liquid 
 contains even only a limited quantity of organic matter, the 
 copper test is the only one that can be reliably applied. 
 
 Nitric acid may be separated and purified from organic mat- 
 ters, -by neutralising the solution, if this has not already been 
 
136 NITRIC ACID. ^ 
 
 done, with pure carbonate of potash or of soda, whereby the' 
 acid will be converted into nitrate of potash or of soda, as the 
 case may be ; the liquid is then, after filtration if necessary, 
 concentrated at a moderate heat until a small portion removed 
 to a watch-glass deposits crystals on cooling, when the mass of 
 liquid is allowed to stand in a cool place until the crystals have 
 separated. If the crystals consist of the nitrate of potash, they 
 will usually be in the form of long striated six-sided prisms : 
 if, of the nitrate of soda, they usually appear in the form of 
 small obtuse rhombohedra. As both of these salts are freely 
 soluble in water, much of the salt may fail to separate from 
 the liquid. The crystals are now removed from the liquid, 
 drained and dried. By again concentrating the decanted liquid, 
 a second crop of crystals may be obtained. If the crystals be 
 highly colored, as will usually be the case when obtained from 
 very complex organic mixtures, they are coarsely powdered aiid 
 washed with absolute alcohol, which will remove much of the 
 foreign matter without dissolving more than a mere trace of the 
 salt. They are then dissolved, by the aid of a gentle heat, 
 in a small quantity of pure water and again separated by 
 recrystallisation, when they will generally be sufficiently pure 
 for the application of any of the tests. A small crystal may 
 now be examined by the brucine test, and the result confirmed 
 by some of the other tests, especially the copper method. 
 Although the copper reaction is the least delicate of the several 
 tests for nitric acid, yet for medico-legal purposes its results are 
 the most satisfactory. 
 
 Contents of the Stomach. — These are carefully collected, their 
 reaction noted, and then gently boiled for some time with a 
 proper proportion of water, the solution filtered, and the con- 
 centrated filtrate examined in the manner above described. 
 Should an alkaline carbonate or a carbonate of lime or mag- 
 nesia, have been administered as an antidote, the whole of the 
 acid may be in the form of a nitrate of one of these bases, and 
 the mixture have a neutral reaction. In case the potash or 
 soda antidote was employed, the examination is conducted as 
 before for the separation of the alkaline nitrate ; but, when the 
 lime or magnesia antidote was administered, the concentrated 
 
QUANTITATIVE ANALYSIS. 137 
 
 filtered solution is treated with carbonate of potash or of soda 
 as long as it produces a precipitate, whereby the base of the 
 earthy nitrate will be converted into an insoluble carbonate, 
 while the acid will be changed into an alkaline nitrate. This 
 mixture is then heated for some minutes to cause the complete 
 subsidence of the" insoluble carbonate, and the solution filtered, 
 after which the filtrate is concentrated and the nitrate separated 
 in its crystalline state. 
 
 From organic fabrics. — Stains produced by this acid on arti- 
 cles of clothing and like substances, have usually at first a more 
 or lessy yellow color, then become reddish, and after a time 
 yeUowish-brown. The presence of the acid may be determined 
 by boiling the stained portion of the article in a very small 
 quantity of pure water, filtering, and concentrating the filtrate, 
 when, if even only a minute quantity of the acid is present, the 
 liquid will have an acid reaction. The solution is then tested in 
 the usual manner. Instead of boiling the stained substance with 
 pure water, it may be boiled with a very dilute solution of car- 
 bonate of potash or of soda, the acid being thus at once con- 
 verted into the form of a nitrate. As nitric acid is volatile and 
 more readily decomposed than sulphuric acid, it much more 
 readily disappears from stained articles of clothing. Neverthe-. 
 less, Dr. Christison detected it in stains on cloth after the lapse 
 of seven weeks ; and Dr. Guy quotes an instance in which it 
 was recovered under similar circumstances, after an interval of 
 some months. 
 
 The yellow stains produced by nitric acid on the skin, after 
 a time assume a brownish-yellow color. When these spots are 
 moistened with a solution of caustic potash, they immediately 
 acquire a bright orange hue, wherein they differ from some- 
 what similar stains occasioned by iodine and bromine, which, at 
 least when recent, on the application of the alkali immediately 
 disappear. 
 
 Quantitative Analysis. — There is no ready method of 
 estimating the amount of nitric acid when in solution with 
 other substances. If the liquid be simply a diluted solution of 
 the acid, the quantity of the latter may be estimated sufficiently 
 
138 HYDROCHLORIC ACID. 
 
 near for most purposes, from the specific gravity of the fluid. 
 When the acid exists in its free state and the solution contains 
 no other acid (except sulphuric), its exact quantity may be 
 determined as follows: The solution is treated with very slight 
 excess of baryta water, and slowly evaporated to dryness: 
 during the evaporation the excess of baryta added will absorb 
 carbonic acid from the atmosphere and become changed into 
 carbonate of baryta, which is insoluble in water. The dry 
 residue is then treated with a sufficient quantity of pure water, 
 and the solution filtered. The filtrate, which now contains the 
 whole of the nitric acid in the form of nitrate of baryta, is 
 treated with diluted sulphuric acid as long as a precipitate is 
 produced; the sulphate ol" baryta thus thrown down, is col- 
 lected on a filter, washed, dried, and weighed. Every one 
 hundred parts by weight of sulphate of baryta thus obtained, 
 correspond to 54 parts of monohydrated nitric acid or 77*2 
 parts of acid of specific gravity 1*424^ every 81 grains of the 
 latter of which measure about one fluid drachm. 
 
 If during the investigation the acid has been converted 
 into nitrate of potash, this is transformed into the sulphate by 
 treating the concentrated solution with sufiicient sulphuric acid. 
 iThe mixture is then cautiously evaporated to dryness, and the 
 residue heated to dull redness, when the nitric acid will be 
 entirely expelled and leave for each equivalent, one equivalent 
 of neutral sulphate of potash. If the residue on cooling be 
 not entirely neutral in its reaction, it is moistened, with a Kttle 
 bicarbonate of ammonia solution and again heated. Every one 
 hundred parts by weight of this salt correspond to 72-4 parts 
 of monohydrated nitric acid. 
 
 Section III. — Hydrochloric Acid. 
 
 Hydrochloric, or muriatic acid, formerly called spirit of salt, 
 as found in commerce, is a more or less yellow, powerfully acid 
 liquid, which evolves irritating fumes when exposed to the air. 
 Veiy few cases of poisoning by this substance are reported, and 
 among these, only perhaps in two instances, was it criminally 
 
PHYSIOLOGICAL EFFECTS. " 139 
 
 administered. In its action, it is somewhat less corrosive than 
 either of the acids already considered. 
 
 Symptoms. — The symptoms produced by hydrochloric acid 
 are very similar to those observed in poisoning by sulphuric 
 acid. When the acid is swallowed in its concentrated state, the 
 patient immediately experiences an intense burning sensation 
 throughout the parts with which the liquid comes in contact, 
 attended with a sense of suffocation and the eructation of gaseous 
 matters. These effects are usually sooner or later succeeded by 
 violent vomiting, great restlessness, intense pain in the stomach, 
 coldness of the extremities, and a small, frequent pulse. At 
 first the tongue and throat usually present a white appearance; 
 in a few instances, white fumes were observed to escape from 
 the mouth soon after the poison had been taken. In some 
 instances, on account of the great soreness of the throat and 
 swollen condition of the neighboring parts, there is great diffi- 
 culty of swallowing. The bowels usually become obstinately 
 constipated, and the urine scanty or entirely suppressed. 
 
 In a case cited by Orfila (Toxicologic, 1852, i, 195), in 
 which a man who had administered to him by mistake about 
 one ounce and a half of hydrochloric acid, there was extreme 
 agitation, with a hot and dry skin, small and hard pulse, fiery-, 
 red tongue, blackness of the lips, hiccough, repeated efforts to 
 vomit, and intense pain in the stomach. These symptoms were 
 followed by vomiting of yellow matters, cold and clammy skin, 
 increased pain, extremely frequent pulse, and continuous delir- 
 ium, and death within about twenty hours after the poison had 
 been taken. 
 
 In a singular case quoted by Dr. Christison (On Poisons, 
 p. 148), a man, with suicidal intent, swallowed a quantity of 
 the acid, and exhibited no signs of uneasiness for some time 
 afterwards; he then, however, suddenly became faint and fell 
 down. In about three hours after the acid had been taken, 
 magnesia and milk were administered; but without relief. He 
 suffered intense thirst, complained of excessive pain in the 
 throat and stomach, and died in about fifteen hours. 
 
 Period when Fatal. — Most of the recorded cases of poisoning 
 by hydrochloric acid were followed by death. The most rapidly 
 
140 HYDROCHLORIC ACID. 
 
 fatal case yet recorded, is, perhaps, that mentioned by Dr. 
 Christison, in which two ounces of an equal mixture of strong 
 hydrochloric acid and tincture of steel (muriated tincture of 
 iron?), caused death in five hours and a half. Vomiting occurred 
 soon after the mixture was taken, but subsequently ceased. 
 Although the patient retained her consciousness until the time 
 of death, she made no complaint either of hfeat or pain any 
 where, or of thirst; but the pulse was imperceptible, and the 
 muscles of the extremities contracted. In three other instances, 
 two of which have already been cited, death took place in 
 fifteen, eighteen, and about twenty hours, respectively. But 
 Dr. Beck cites a case in which a dose of two ounces did not 
 prove fatal until after a period of eight days (Med. Jur., ii, 495). 
 And two instances are recorded in which death did not occur 
 until eight weeJcs had elapsed (Orfila, Toxicol., i, 221; and Taylor 
 on Poisons, p. 291). 
 
 Fatal Quantity. — In a case reported by Dr. Budd, half a 
 fluid ounce of the acid, taken with suicidal intent, proved fatal 
 in eighteen hours to a woman aged sixty-three years. (Wharton 
 and Stille's Med. Jur., p. 494.) This seems to be the smallest 
 fatal dose yet recorded. In this case the following symptoms 
 were observed: vomiting, coUapse, whitening and abrasion of 
 the lips, mouth, and fauces; also, swelling of the throat and 
 inability to swaUow, with stridulous breathing and thick inar- 
 ticulate voice, and intense epigastric pain. Death, without loss 
 of consciousness until near the last, took place by exhaustion. 
 
 On the other hand, Dr. Toothaker reports a case in which 
 a man recovered after having taken, by mistake, one ounce of 
 official muriatic acid. It was immediately succeeded by violent 
 burning of the mouth and fauces, a sense of sufibcation, and 
 spasms. After the administration of olive oil, followed by a 
 mixture of milk and calcined magnesia, copious vomiting ensued. 
 The -strength of the patient became greatly reduced, and the 
 extremities so cold as to require the application of sinapisms. 
 The next day there was pain and costiveness, but these were 
 relieved by a dose of castor oil. After this, the patient very 
 gradually recovered. (Boston Med. and Surg. Journal, vol. 
 XV, p. 270.) 
 
CHEMICAL PROPERTIES. 141 
 
 Treatment. — The proper chemical antidote is either chalk, 
 or calcined magnesia, or a dilute solution of an alkaline 
 carbonate. If neither of these substances be at hand, milk, 
 white of egg, oil, or demulcents of any kind, should be freely 
 administered. In every respect, the treatment is the same as 
 in sulphuric acid ppisoning [ante p. 101). 
 
 Post-mortem Appearances. — In acute cases, the mucous 
 membrane of the mouth, throat, and oesophagus, is usually more 
 or less softened, and of a whitish or brownish color. The lining 
 membrane of the stomach is generally highly inflamed, softened, 
 and readily separated. In the case cited above which proved 
 fatal in five hours and a half, the lower portion of the oesoph- 
 agus had the appearance of being charred. The mucous mem- 
 brane of the stomach presented black elevated ridges, as if 
 charred, while the intervening furrows were of a scarlet-red 
 color; similar appearances were observed in the duodenum and 
 jejunum. In Dr. Budd's case, the mucous membrane of the 
 mouth, fauces, and larynx, was whitened and softened, the soft 
 palate and tonsils swollen, and a portion of the lining membrane 
 of the larynx was entirely removed. In this case, the local 
 action of the poison was chiefly confined to the parts just 
 mentioned. 
 
 In the case cited by Orfila which did not prove fatal until 
 after a period of eight weeks, the lining membrane of the throat 
 and oesophagus was thickened, and in a state of suppuration. 
 The stomach was entirely disorganised, softened, and presented 
 several round perforations, having thickened and inflamed 
 edges; the pyloric orifice was thickened and contracted. In 
 the small intestines, the mucous membrane throughout its ex- 
 tent was thickened, injected in patches and of an arborescent 
 appearance; the large intestines were healthy, and contained a 
 brownish, fetid liquid. 
 
 Chemical Properties. 
 
 General Chemical Nature. — Anhydrous hydrochloric acid 
 is a gaseous compound of hydrogen and chlorine (HCl). It is 
 a colorless, powerfully suffocating gas, having a density of 1-26; 
 
142 
 
 HYDROCHLORIC ACID. 
 
 when it comes in contact with the air, it produces white fumes, 
 due to its strong affinity for water. 
 
 Hydrochloric, or muriatic acid of the shops, is an aqueous 
 solution of the gaseous compound, of which, according to Davy, 
 water at a temperature of 40°, will absorb 480 times its volume, 
 increasing both in volume and density. Such a solution has a 
 specific gravity of 1-21, and contains nearly 43 per cent, of an- 
 hydrous acid. The solution is colorless, has a highly irritating 
 odor, and yields dense white fumes when a rod moistened with 
 ammonia is presented to it. If the solution be heated, a portion 
 of the anhydrous acid is readily expelled in the form of vapor. 
 
 The following table, according to E. Davy, exhibits the per 
 cent, by weight, of the anhydrous acid in pure aqueous solutions 
 of different specific gravities : — 
 
 STRENGTH OF ACJUEOUS SOLUTIONS OF HYDROCHLORIC ACID. 
 
 SP. OB. 
 
 FEB CENT. 
 
 SP. OB. 
 
 FEB CEMT. 
 
 BP. SB. 
 
 FEB CENT. 
 
 1-21 
 
 42-43 
 
 1-14 
 
 28-28 
 
 1-07 
 
 14-14 
 
 1-20 
 
 40-80 
 
 1-13 
 
 26-26 
 
 1-06 
 
 12-12 
 
 1-19 
 
 38-38 
 
 1-12 
 
 24-24 
 
 1-05 
 
 10-10 
 
 1-18 
 
 36-36 
 
 1-11 
 
 22-22 
 
 1-04 
 
 8-08 
 
 i.ir 
 
 34-34 
 
 1-10 
 
 20-20 
 
 1-03 
 
 6-06 
 
 1-16 
 
 32-32 
 
 1-09 
 
 18-18 
 
 1-02 
 
 4-04 
 
 1-15 
 
 30-30 
 
 1-08 
 
 16-16 
 
 1-01 
 
 2-02 
 
 Hydrochloric acid as found in the shops, has usually a 
 density of about 1-15 ; and a more or less yellow color, due to 
 the presence of free chlorine gas or chloride of iron, or both. 
 It is also liable to be contaminated with sulphuric and sulphur- 
 ous acids, arsenic, nitric acid and some of the lower oxides of 
 nitrogen, and common salt; occasionally, other impurities are 
 present. 
 
 Liquid hydrochloric acid is readily decomposed by iron, 
 zinc, and the stronger electro-positive metals, with the forma- 
 tion of a chloride of the metal and the evolution of hydrogen 
 gas. But it is unacted upon by metallic copper, even at the 
 boiling temperature; in this respect it differs from nitric and 
 sulphuric acids. It is readily decomposed by the basic metallic 
 oxides and their carbonates, with the formation of a chloride 
 
SPECIAL CHEMICAL PROPERTIES. 143 
 
 and wa,ter, and, in the case of a carbonate, the evolution of 
 carbonic acid. 
 
 The salts resulting from this acid, or chlorides as they are 
 termed, are mostly colorless, and with the exceptions of the 
 chlorides of silver and lead and the sub-chloride of mercury, 
 are freely soluble in water. When heated with diluted sulphuric 
 acid, the soluble chlorides, together with water, are readily de- 
 composed, giving rise to a sulphate and evolving hydrochloric 
 acid gas, thus: NaCl + HO, 803 = NaO, SO3 + HCI. 
 
 Special Chemical Properties. — When hydrochloric acid is 
 heated with black oxide of manganese, both compounds undergo 
 decomposition with the formation of the chloride of the metal 
 and the evolution of free chlorine, thus : MnOj + 2 HCl = 2 HO + 
 MnCl + Cl. The presence of the eHminated chlorine may be 
 recognised by its peculiar odor, its bleaching properties, and, if 
 not in too minute quantity, its greenish-yeUow color. Its bleach- 
 ing property is readily determined by exposing to it a slip of 
 moistened htmus-paper, or a slip of paper moistened with a 
 solution of indigo ; if a slip of starch-paper be moistened with 
 a solution of iodide of potassium and exposed to the gas, it im- 
 mediately acquires an intense blue color, which after a time, 
 under the continued action of the gas, is partially or wholly 
 discharged. If the evolved gas be brought in cdntact with a 
 drop of a solution of nitrate of silver, or be conducted into a 
 solution of this salt, it produces, in the first instance a white 
 film and in the second a white precipitate, of chloride of silver, 
 having the properties to be presently described. 
 
 When a soluble chloride is mixed with black oxide of man- 
 ganese, and heated with sulphuric acid, previously diluted with 
 .about an equal volume of water, the whole of the chlorine is 
 ehminated in its free state. The reactions in this case, taking 
 bhloride of sodium as the type, are as follows: NaCl + Mn02+ 
 2 S03=MnO, SOj + NaO, SOj+Ch The presence of the evolved 
 chlorine may be determined by the methods just indicated. If 
 this decomposition be conducted in a thin watch-glass covered 
 by an inverted glass containing slips of the moistened test 
 papers, the fractional part of a grain of the salt will yield sat- 
 isfactory results. 
 
144 HYDROCHLORIC ACID. 
 
 Since the compounds resulting from hydrochloric acid are, 
 with very few exceptions, freely soluble in water, there are but 
 few reagents that precipitate it from solution. In the following 
 investigations in regard to the behavior of solutions of hydro- 
 chloric acid, puiw aqueous solutions of the free acid were chiefly 
 employed. The fractions indicate the amount of the anhydrous 
 acid ia solution in one grain of liquid, and the results, the 
 behavior of one grain of the solution. 
 
 1. Nitrate of Silver. 
 
 Nitrate of silver throws down from solutions of hydrochloric 
 acid, of chlorides, and of fi'ee chlorine, a white amorphous pre- 
 cipitate of chloride of silver (Ag CI), which is readily soluble 
 in ammonia, but insoluble in nitric and sulphuric acids; it is 
 also readily soluble in cyanide of potassium, but insoluble in 
 the fixed caustic alkalies. When exposed to light, chloride of 
 silver soon acquires a purple color; on the application of heat, 
 it readily fuses without decomposition, to a yellowish liquid, 
 which on cooling solidifies to a hard, compact, nearly colorless 
 mass. 
 
 1. Yoo grain of anhydrous hydrochloric acid, in one grain of 
 
 water, yields a very copious, curdy precipitate. 
 
 2. 1,000 grain: much the same results as 1. 
 
 3. 10,0 grain, yields a very good flocculent precipitate. The 
 
 solution strongly reddens litmus-paper. 
 
 4. 5 0,000 grain: a very satisfactory deposit. The solution, 
 
 after a time, slightly reddens litmus-paper. 
 
 5. TToTooT) grain: in a few moments, a distinct cloudiness, which 
 
 soon becomes well-marked. 
 
 6. TooVoo grain, yields after a little time, a slight opalescence. 
 
 Nitrate of silver also produces in solutions of hydrocyanic acid, 
 even when strongly acidulated, a white precipitate of cyanide 
 of silver, which, like the corresponding chlorine compound, is 
 soluble in ammonia (although less freely), and insoluble in nitric 
 acid. But the cyanide of silver, when dried and heated in a 
 reduction tube, readily undergoes decomposition, with the evolu- 
 tion of an inflammable gas, in which respects it differs from the 
 
SPECIAL CHEMICAL PROPERTIES. 145 
 
 chlorine salt. A more ready method of distinguishing between 
 these acids, is to treat a portion of the suspected solution with 
 the mercury reagent described below. 
 
 In neutral solutions, nitrate of silver produces precipitates 
 with several other acids or elements. All of these precipitates, 
 however, except that from hydrocyanic acid, unlike the chloride 
 of silver, are readily soluble in nitric acid, at least in its con- 
 centrated state. So again, the reagent is readily decomposed, 
 with the production of a white precipitate, by a great variety 
 of organic substances; these precipitates, however, like those 
 just mentioned, are soluble in nitric acid. 
 
 The chlorine may be recovered in a soluble form from the 
 chloride of silver, by fusing the latter with a mixture of car- 
 bonate of soda and potash, when the chlorine will be transformed 
 into an alkaline chloride, readily soluble in water. 
 
 2. Nitrate of Suboxide of Mercury. 
 
 This reagent produces in solutions of free hydrochloric acid 
 and of chlorides, a white amorphous precipitate of subchloride 
 of mercury, or calomel (HgaCl), which is insoluble in concen- 
 trated nitric acid. The precipitate is readily decomposed by 
 the caustic alkalies, with the formation of a black compound 
 of mercury. 
 
 1. y^ grain of the anhydrous acid, yields a very copious 
 
 precipitate. 
 
 2. ],ooo grain, yields much the same results as 1. 
 
 3. 10.000 grain: a quite good precipitate. 
 
 4. so.^oo Ti grain: a very satisfactory deposit. 
 
 5. 1 o! Q grain, yields after a little time, a very distinct 
 
 turbidity. 
 Nitrate of suboxide of mercury, also produces white pre- 
 cipitates in solutions of several other substances. When the 
 reagent is added to a solution of free hydrocyanic acid, as weU 
 as of a cyanide, one half of the mercury is thrown down in its 
 finely divided state as a dark grey precipitate, while the other 
 portion remains in solution in the form of cyanide of mercury. 
 This reaction, as intimated above, readily serves to distinguish 
 
 10 
 
146 HYDROCHLORIC ACID. 
 
 between hydrochloric and hydrocyanic acids, as well as between 
 their salts. 
 
 3. Acetate of Lead. 
 
 Acetate of lead produces in solutions of hydrochloric acid 
 and of its salts, when not too dilute, a white precipitate of 
 chloride of lead (Pb CI), which is somewhat less soluble in 
 diluted nitric acid than in pure water. The precipitate is 
 rather freely soluble in boiling water, from which on cooling 
 it separates in its crystalline state. 
 
 1- Toir grain of hydrochloric acid, when treated with the re- 
 agent, crystals immediately begin to separate, and in a 
 httle time there is a quite good crystalhne deposit, Plate 
 
 ni, fig. 1. 
 
 2. yoir grain: on agitating the mixture with a glass rod, it 
 yields after a few minutes, some few crystals of chloride 
 of lead, which are chiefly confined to the margin of the 
 drop. 
 Acetate of lead also produces white precipitate — usually, 
 however, amorphous — in solutions of several other acids, espe- 
 cially if the mixture be neutral. Moreover, the reagent is 
 readily decomposed by various organic substances, with the 
 production of a white amorphous precipitate. 
 
 Separation from Organic Mixtures. 
 
 Suspected Solutions. — -If the solution has a strong acid reac- 
 tion, and is tolerably free from organic matter, a small portion 
 of the liquid may be treated with a few drops of a strong 
 solution of nitrate of silver." If this produces a white precip- 
 itate, which when washed in diluted nitric acid is insoluble' 
 in the stronger acid, there is little doubt of the presence of 
 chlorine. If this examination indicates the presence of chlorine, 
 it then becomes necessary, even should the solution have a 
 strong acid reaction, to determine whether it existed in the 
 form of free hydrochloric acid or as a chloride. For this 
 purpose, a portion of the solution is evaporated to dryness, and 
 gently ignited, when if it leaves no saline residue, it is quite 
 
SEPARATION FROM ORGANIC MIXTURES. 147 
 
 certain that the acid was uncombined. Should, however, it 
 leave such a resiHue, this is dissolved in water and tested for 
 chlorine. If this element be absent, it is most probable that 
 the acid was free; however, a mixture of a chloride, as com- 
 mon salt, and excess of sulphuric acid, would, as heretofore 
 pointed out in the consideration of the recovery of sulphuric 
 acid, yield upon evaporation a residue entirely free from chlo- 
 rine. Whether these conditions really existed, could be readily 
 determined by treating a portion of the suspected solution with 
 chloride of barium, when if it failed to yield a precipitate or 
 gave one readily soluble in nitric acid, the absence of sulphuric 
 acid would be fully established. 
 
 Should the suspected liquid on evaporation leave a residue 
 containing a chloride, it then becomes necessary to ascertain 
 whether the whole of the hydrochloric acid may have existed 
 in that form. To effect this, a given portion of the liquid is 
 neutralised by pure carbonate of soda, evaporated to dryness, 
 the incinerated residue dissolved in water containing a little 
 nitric acid, the chlorine precipitated by nitrate of silver, and 
 the precipitate collected, washed, dried, and weighed: an equal 
 volume of the liquid, without the addition of carbonate of soda, 
 is then evaporated to dryness, the residue incinerated, and the 
 chlorine precipitated, as in the previous operation, by nitrate 
 of silver. If the weight of the precipitate obtained by the 
 former of these methods exceed that obtained by the latter, 
 then a portion of the acid existed in its free state : the exact 
 quantity of the acid thus present, may of course, be readily 
 deduced from the difference thus observed. 
 
 For the separation of free hydrochloric acid from complex 
 mixtures containing organic solids, it has been proposed to heat 
 the mixture, after the addition of water if necessary, to near 
 the boiling temperature, then filter, and distiU the filtrate at a 
 gentle heat to the consistency of a thin syrup, the distillate 
 being collected in a proper receiver. The liquid thus collected 
 is then examined by the silver test. As, however, hydrochloric 
 acid strongly adheres to organic matter, none of the acid, unless 
 present in comparatively large quantity, may pass over into the 
 receiver. Under these circumstances, Orfila recommended to 
 
148 HYDROCHLORIC ACID. 
 
 treat the residue in the retort with a solution of tannin, filter, 
 and then distill the filtrate, as before, to near dryness. From 
 what has already been stated, it is obvious that if the mixture 
 thus distilled contained a chloride and free sulphuric acid, it 
 would give rise to hydrochloric acid, which would appear in the 
 distillate. This objection could of course be answered by test- 
 ing a portion of the residue with chloride of barium. 
 
 Contents of the Stomach. — Any solids present are cut into 
 small pieces and the mass, after dilution with distilled water if 
 necessary, kept at near the boiling temperature for half an hour 
 or longer, then strained, the strained liquid filtered, and then 
 submitted to the process of distillation described above. If, 
 however, an alkaline or earthy antidote has been administered 
 and the mixture has a neutral reaction, then a given portion of 
 the filtered liquid is evaporated to dryness, the incinerated 
 residue dissolved in water, and any chlorine present estimated 
 in the form of chloride of silver. In these investigations, it 
 must be borne in mind that the gastric juice contains not only 
 alkaline chlorides, but also free hydrochloric acid ; and more- 
 over, that common salt, or chloride of sodium, is almost uni- 
 versally present, at least in minute quantity, in articles of food. 
 The gastric juice, however, according to most observers, nor- 
 mally contains only the merest trace of the free acid ; but the 
 chlorides exist in very notable quantity. 
 
 From the facts just stated, it is obvious that the detection of 
 a mere trace of free hydrochloric acid or of a chloride in minute 
 quantity, would not in itself be any evidence of poisoning by 
 this acid. If it be shown that the base of the chloride present 
 corresponds to that of the antidote alleged to have been admin- 
 istered, this fact may materially assist in forming an opinion as 
 to the true nature of the case. When the whole of the acid 
 has been converted into a chloride, by the administration of an 
 antidote, it may be recovered in its free state by first evapora- 
 ting the mixture to dryness, then distilling the incinerated resi- 
 due with strong sulphuric acid, and collecting the evolved acid 
 in a small quantity of water contained in a well-cooled receiver. 
 
 From organic fairies. — Stains produced by this acid on 
 articles of clothing, and like substances, may be examined by 
 
QUANTITATIVE ANALYSIS. 149 
 
 gently boiling the stained portion with pure water for some 
 miautes, and testing the filtered liquid in regard to its reaction 
 upon litmus-paper, and with a solution of nitrate of silver. 
 When chlorine is thus discovered, it should be determined, in 
 the manner already pointed out, whether it exists in the form of 
 the free acid or simply as a chloride. As hydrochloric acid is 
 volatile, it sooner or later entirely disappears from stains of 
 this kind. 
 
 Quantitative Analysis. — The quantity of free hydrochloric 
 acid, or its equivalent in the form of a soluble chloride, is most 
 readily determined by precipitating it as chloride of silver. 
 The solution is treated with a solution of nitrate of silver as 
 long as it yields a precipitate, and the mixture gently heated 
 until the whole of the precipitate has deposited ; the precipitate 
 is then collected on a small filter, thoroughly washed, dried, and 
 weighed. Every one hundred parts, by weight, of chloride of 
 silver thus obtained, correspond to 25'43 parts of anhydrous 
 hydrochloric acid, or about 81 parts of liquid acid of specific 
 gravity 1-15; one fluid drachm of the latter acid weighs about 
 sixty-five and a half grains. 
 
150 OXALIC ACID. 
 
 CHAPTER III. 
 
 OXALIC ACID, HYDROCYANIC ACID, PHOSPHORUS. 
 
 Section I. — Oxalic Acid. 
 
 History. — Oxalic acid, in its crystalline state, is an organic 
 compound of the elements carbon and oxygen with water. It 
 is found in the common rhubarb-plant, wood-sorrel, and several 
 other plants, and is occasionally met with in the human urine, 
 only, however, as an abnormal product. For commercial pur- 
 poses, it is usually obtained by the action of nitric acid upon 
 starch or sugar. In its uncombined state, it is a white crystal- 
 line solid, having an intensely acid taste. From its close resem- 
 blance to sulphate of magnesia, or Epsom salt, it has on several 
 occasions been fatally mistaken for that substance. Either alone, 
 or in combination in a soluble form, it is a powerful poison, and 
 has in several instances been administered as such ; but it has 
 much more frequently been taken for the purpose of self- 
 destruction. 
 
 Symptoms. — The symptoms produced by oxalic acid, depend 
 not only on the quantity taken, but also, somewhat, on the de- 
 gree of concentration under which it exists. When swallowed 
 in large quantity and in a concentrated state, it produces an 
 immediate burning pain in the mouth and throat, succeeded by 
 vomiting and intense pain in the stomach ; and as the case 
 advances, great muscular prostration, with hurried respiration, 
 pale and anxious countenance, cold and clammy skin, small and 
 feeble pulse, and in some instances, delirium and convulsions. 
 The vomited matters have not unfrequently contained blood. 
 
 When the dose is not large or is much diluted, nothing more 
 than a strongly acid taste may be experienced in the mouth 
 and throat, and the pain in the stomach, as well as the vomit- 
 ing, may be much delayed. Although early and continuous 
 
PHYSIOLOGICAL EFFECTS. 151 
 
 vomiting is a common symptom, yet it has in some cases been 
 entirely absent. In a case quoted by Dr. Christison, a man 
 swallowed half an ounce of the poison, dissolved in ten parts of 
 water, without experiencing any pain in the abdomen for six 
 hours, and there was no vomiting for seven hours, except when 
 emetics were administered. In most of the instances in which 
 no vomiting occurred, the dose was either small or greatly 
 diluted ; but this symptom has been absent, when the poison 
 was taken in large quantity, and in a concentrated state. 
 
 In a protracted case reported by Dr. C. T. Jackson (Boston 
 Med. and Surg. Journal, vol. x.xx, p. 17), the following symp- 
 toms, were observed. A man, aged thirty years, took in solution 
 about one ounce of crystallised oxalic acid, mistaking it for 
 Epsom salt. He immediately perceived, by the strong acid 
 taste and burning sensation in the throat, that he had made a 
 mistake, and he drank a large quantity of warm water to excite 
 vomiting, which produced the desired effect. He also took, by 
 the advice of a physician, ipecacuanha and antimony in emetic 
 doses, and castor oil. The matter first vomited, was of a dark 
 chocolate color. In twelve hours after the occurrence, the 
 patient was in, a state of complete prostration: face, lips, throat, 
 and tongue, swollen and livid ; pulse almost extinct, fluttering, 
 and irregular ; heart, in a continual fluttering palpitation ; great 
 jactitation and distress ; with incessant vomiting. The matter 
 vomited, was a thick, grumous, and jelly-like fluid, of a yellow 
 color, mixed with white flocculi. He complained of no pain at 
 the epigastrium, or over the bowels, on pressure. Carbonate of 
 lime was now administered, but rejected. On the second day, 
 the face was tumid, and of a livid color ; tongue swollen and 
 livid; pulse 130; and the urine entirely suppressed. The vom- 
 iting continued for two or three days, with great distress and 
 anxiety ; the tongue became covered with a brown coating, the 
 tip of the organ being red and dry ; and there was great thirst, 
 but no pain. On the sixth day, his mind began to wander, and 
 petechiee appeared on the face, chest, and other parts of the 
 body, which appeared as if sprinkled with blood. He con- 
 tinued to fail, and died on the tenth day after the poison had 
 been taken. In several of the reported cases, there was great 
 
152 OXALIC ACID. 
 
 irritability of the bowels, with frequent purging, and the dis- 
 charged matters in some instances contained blood. 
 
 Period when fatal. — Much the larger proportion of the 
 recorded cases of poisoning by oxalic acid proved fatal; and 
 among these, death in most instances, perhaps, occurred in less 
 than an hour after the poison had been taken. In a case quoted 
 by Dr. Taylor, an unknown quantity of the poison caused death 
 in about tJiree minutes (On Poisons, p. 312). And Dr. Christi- 
 son refers to two cases which proved fatal in about ten minutes ; 
 and in another, death ensued in from fifteen to twenty minutes. 
 In a case mentioned by .Dr. Pereira, death occurred in twenty 
 minutes. Death also occurred within a similar period, in an 
 instance in which the patient vomited almost immediately after 
 the poison had been taken. 
 
 The fatal period has however been delayed for many hours, 
 and even days. Two instances are reported in which death did 
 not occur until thirteen hours had elapsed ; and another, in 
 which it was delayed until the fifth day. In Dr. Jackson's case, 
 already mentioned, life was prolonged until the tenth day. The 
 most protracted case yet recorded, is, perhaps, that mentioned 
 by Dr. Beck (Med. Jur., ii, p. 499), in which a woman died 
 from the secondary effects of the poison, after a period of some 
 months. 
 
 Fatal Quantity. — The effects of given quantities of oxalic 
 acid, like those of most other poisons, have been far from uni- 
 form. In one of the cases just referred to, that proved fatal in 
 thirteen hours, half an ounce of the poison, largely diluted with 
 water, had been taken. Dr. Taylor quotes a case in which a 
 boy, aged sixteen years, ate about one drachm of the solid acid, 
 and it proved fatal within nine hours ; and another, in which a 
 woman, aged twenty-eight years, swallowed three drachms of 
 the crystallised acid and was found dead in one hour afterwards. 
 These are the smallest fatal doses yet reported. Serious symp- 
 toms, however, have followed the taking of much smaller quan- 
 tities of the poison. In a case reported by Dr. Babington, two 
 scruples of the acid, taken in combination with carbonate of 
 soda, caused severe symptoms, from which the patient did not 
 entirely recover until some weeks afterwards. 
 
ANTIDOTES. 153 
 
 On the other hand, complete recovery has taken place after 
 very large quantities of oxalic acid had been taken. Not less 
 than six instances of this kind are reported, in each of which 
 half an ounce of the acid had been swallowed : in most of these, 
 however, early treatment was employed. A like result has also 
 been observed in several instances in which an ounce of the 
 poison had been taken. In a singular case quoted by Wharton 
 and Stills (Med. Jur., p. 496), a woman dissolved two large 
 tablespoonfuls of oxalic acid, by mistake for Epsom salt, in a 
 small quantity of water, and took it on an empty stomach. 
 Some twenty minutes afterwards she vomited, at first the solu- 
 tion she had taken, and then a dark-colored, bloody fluid, in 
 which were numerous white flakes. Ipecacuanha and after- 
 wards prepared chalk were administered, and in about an hour 
 she was found quiet and nearly free from the intense burning 
 pain in her stomach and throat. She subsequently vomited 
 again, and matters similar to those vomited were discharged 
 from the bowels by purging. Soon after this she entirely recov- 
 ered. If this case is correctly reported, the quantity of the 
 poison taken, was about one ounce and a quarter. 
 
 Treatment. — Powdered chalk, magnesia, or its carbonate, 
 suspended in water or milk, or a solution of the bicarbonate 
 of magnesia, should be administered as speedily as possible. 
 Either of these substances wiU completely neutralise oxalic acid, 
 with the production of an insoluble compound. After thus neu- 
 tralising the poison, if there is not free vomiting, an emetic 
 should be administered. Large draughts of warm water may 
 be given to aid the vomiting. One or other of these chemical 
 antidotes has in several instances been employed with great 
 advantage. When however the symptoms have once fully man- 
 ifested themselves, they usually terminate fatally in spite of any 
 treatment. 
 
 If neither of these earthy compounds is at hand, an emetic 
 should be given, and its exhibition followed by large quantities 
 of tepid water. The stomach-pump may sometimes be em- 
 ployed with advantage. As the alkaline carbonates form with 
 the acid, soluble poisonous salts, they will not serve as antidotes 
 in this kind of poisoning. 
 
154 OXALIC ACID. 
 
 Post-mortem Appearances. — These are subject to consid- 
 erable variation. In rapidly fatal cases, the mucous membrane 
 of the mouth and throat is generally more or less disorganised, 
 and of a white appearance. The lining membrane of the oesoph- 
 agus is sometimes much softened, and easily detached, and the 
 blood-vessels congested with dark blood. The stomach has been 
 found much contracted in size, and its external coat highly 
 inflamed. The contents of this organ are usually thick, highly 
 acid, 'and of a dark color, due to the presence of altered blood. 
 The mucous membrane is pale or of a brownish color, injected, 
 softened, and sometimes corrugated. In a few instances, the 
 coats of the stomach presented a dark or nearly black appear- 
 ance ; and they have been so much' softened, as to be lacerated 
 by the slightest pressure. In a case mentioned by Dr. Christi- 
 son, the coats of the stomach were perforated. The small intes- 
 tines have in several instances shown signs of irritation ; and 
 the liver and spleen have been found in a highly congested 
 state. In this connection, it is important to bear in mind, that 
 oxalic acid, even when taken in large quantity, has in some 
 few instances destroyed life, without leaving any well-marked 
 morbid changes, or in fact any abnormal appearance whatever, 
 in the dead body. 
 
 In a case which proved fatal in thirteen hours, the lining 
 membrane of the throat and oesophagus presented an appearance 
 similar to that of having been scalded, and could be easily sep- 
 arated. The stomach contained a pint of thick, dark-colored 
 fluid ; and its mucous coat was pulpy, in many points black, 
 and in others highly inflamed; its outer coat was also inflamed. 
 Similar appearances, but in a less degree, were observed both 
 externally and internally in the small intestines^ The lining 
 membrane of the trachea was also very red. 
 
 In the protracted case reported by Dr. Jackson, the stomach 
 contained a yellow fluid, and was remarkably corrugated ; its 
 mucous membrane was much thickened, soft, of a bright-red 
 color, and contained numerous small ulcers. The lining mem- 
 brane of the duodenum was also thickened, red, and studded 
 with ulcers; and that of the other portions of the small intes- 
 tines congested. The large intestines, and other abdominal 
 
GENERAL CHEMICAL NATURE. 155 
 
 organs, were healthy. The heart was empty, except a small 
 quantity of blood in the right side. In a case that proved fatal 
 on the twenty-third day, the lining membrane of the CESophagus 
 and stomach was completely destroyed, and in places entirely 
 removed ; and the muscular coat, throughout the gullet and 
 stomach, was much thickened, highly injected, and presented a 
 dark appearance. 
 
 Chemical Properties. 
 
 General Chemical Nature. — Oxalic acid, when pure, forms 
 colorless, transparent, odorless, four-sided crystalline prisms, 
 which contain two equivalents of water of crystallisation (HO, 
 C2O3, 2 Aq). It is the strongest of the vegetable acids. The 
 crystals are permanent, at ordinary temperatures ; but when 
 exposed to warm air, they part with their water of crystallisa- 
 tion, and become opake. 
 
 Oxalic acid is readily soluble in water at ordinary tempera- 
 tures. The extent to which the acid dissolves in this fluid has 
 been variously stated, at from eight to fifteen times its weight 
 of the liquid. And in fact, either of these extremes will equally 
 express its solubility, unless some exact temperature be specified. 
 As the mean result of three very closely accordant experiments, 
 we have found, that when excess of the pure crystallised acid 
 is kept in contact with pure water for five hours at a tempera- 
 tur.e of 60°, and the solution then filtered, the filtrate contains 
 one part of the acid in 9-5 parts of water. It is more freely 
 soluble in warm water; and boiling water, it is said, will take 
 up its own weight of the acid. Berzelius met with a sample of 
 the crystallised acid, which was so strongly impregnated with 
 nitric acid, used in its preparation, that it required only two 
 parts of cold water for solution. The pure acid is also freely 
 soluble in alcohol, but insoluble in ether, and very sparingly 
 soluble in chloroform. When one grain of the pure crystallised 
 acid is dissolved in one hundred grains of water, and the solu- 
 tion violently agitated, for a few moments, with an equal volume 
 of pure chlorofonn, this liquid extracts one-twentieth of a grain 
 of the acid. 
 
156 OXALIC ACID. 
 
 The oxalates, or salts of this acid, are usually colorless and 
 crystaUisable, and for the most part, except those of the alkalies, 
 insoluble in water. They are all decomposed by heat, the acid 
 being resolved into carbonic acid and carbonic oxide. 
 
 Special Chemical Peopeeties. — Oxalic acid, when pure, 
 is entirely dissipated at a temperature of about 350° F. In 
 this respect, it diiFers from the sulphate of magnesia, which it 
 closely resembles in appearance, and which leaves a fixed resi- 
 due, even at high temperatures. When the acid is heated 
 with strong sulphuric acid, it is resolved, without charring, into 
 carbonic acid and carbonic oxide gases, which escape: tartaric 
 and other organic acids when thus heated, are speedily charred. 
 Solutions of the acid have a strongly acid taste and reaction, 
 even when much diluted, and fail to be precipitated by the 
 alkaline carbonates : a solution of Epsom salt has a bitter taste, 
 is neutral in its reaction, and yields a white precipitate when 
 treated with carbonate of soda. 
 
 Pure aqueous solutions of oxalic acid, when slowly evapo- 
 rated to dryness, leave the acid in the form of long crystalline 
 prisms. When one grain of a 100th solution of the acid is 
 allowed to evaporate spontaneously, it leaves a comparatively 
 large mass of crystals; when the solution contains the 1,000th 
 part of a grain of the acid, it yields a quite good deposit, the 
 crystals having the forms represented in Plate III, fig. 2; the 
 10,000th part of a grain of the acid, under similar circum- 
 stances, yields a very satisfactory deposit of small prisms and 
 cros slots. 
 
 In the following details in regard to the behavior of solu- 
 tions of oxalic acid, the fractions indicate the fractional part 
 of a grain of the pure crystallised acid in solution in one grain 
 of water; and the results refer to the reactions of one grain of 
 the solution. 
 
 1. Nitrate of Silver. 
 
 Solutions of free oxalic acid, and of its alkaline salts, yield 
 with nitrate of silver, a white amorphous precipitate of oxalate 
 of silver (AgO, C2O3), which is slowly soluble in cold nitric acid, 
 but readily soluble in the heated acid; it is also readily soluble 
 
SPECIAL CHEMICAL PROPERTIES. 157 
 
 in solutions of ammonia, but insoluble in concentrated solutions 
 of acetic, tartaric, and oxalic acids. When the dried precipitate 
 is heated on platinum foil, it is decomposed and dissipated in 
 slightly detonating puffs, being resolved into metallic silver and 
 carbonic acid gas, thus: AgO, C203=Ag + 2 CO2. 
 !• xhy grain of oxalic acid, in one grain of water, yields a 
 
 very copious precipitate, which, in the mixture, requires 
 
 about three drops of strong nitric acid for complete solution. 
 
 When dried and heated, it is dissipated in the manner 
 
 peculiar to this salt. 
 
 2. iTFoT) grain, yields a rather copious precipitate, which, when 
 
 dried and heated, is rapidly dissipated; but not in distinct 
 puffs. 
 
 3. lo.ouu grain: a very good deposit. 
 
 4. 5o,ouu grain, yields an immediate turbidity, and in a very 
 
 short time, a quite satisfactory deposit. 
 
 5. 1 0% grain: an immediate opalescence, and after a little 
 
 time, a quite distinct deposit. 
 
 6. 5oo%Qu grain, yields after some minutes, a distinct cloudiness. 
 Fallacies. — Nitrate of silver is also readily decomposed with 
 
 the production of a white precipitate, by a great variety of 
 organic principles. And it also produces similar precipitates 
 with several other acids, especially from neutral solutions. Thus 
 it occasions precipitates in neutral solutions of the carbonates, 
 tartrates, phosphates, borates, citrates, chlorides, and cyanides, 
 and also, in most instances, with the free acids of these salts. 
 AU these precipitates, however, except those from the chlorides, 
 cyanides, and their free acids, are soluble in acetic acid, in which 
 respect they differ from the oxalate of silver. So, also, the 
 chloride and cyanide of silver — produced by the reagent from 
 solutions of chlorides and cyanides or their free acids — are 
 readily distinguished from the oxalic acid precipitate, in that 
 they are insoluble in nitric acid. Moreover, the chloride of 
 silver, when dried and heated, quietly fuses without decomposi- 
 tion; and the cyanide, under similar circumstances, is decom- 
 posed with the production of a Jixed residue and the evolution 
 of an inflammable gas. The precipitates produced from the 
 carbonates, tartrates, phosphates, borates, and citrates, when 
 
158 OXALIC ACID. 
 
 dried and heated, also,- unlike the oxalic acid deposit, leave a 
 fixed residue. 
 
 2. Sulphate of Lime. 
 
 Sulphate of lime throws down from solutions of free oxalic 
 acid, and of soluble oxalates, a white granular precipitate of 
 oxalate of lime (CaO, CjOg, 2Aq), which is readily soluble in 
 nitric and hydrochloric acids, but insoluble, or very nearly so, 
 in acetic and other vegetable acids. As sulphate of lime is 
 soluble only to a limited extent in water, its solution does not 
 precipitate the whole of the oxalic acid from somewhat con- 
 centrated solutions, unless the reagent solution be added in very 
 large quantity. From such solutions, the whole of the acid 
 may be readily precipitated, as oxalate of lime, by employing 
 as the reagent, a solution of chloride of calcium or any of the 
 other more soluble salts of lime. 
 
 1 • ToTT grain of free oxalic acid, yields with a drop of sulphate 
 of lime solution, a very good, granular precipitate. A 
 small drop of chloride of calcium solution produces a much 
 more copious deposit, and which is in the form of small 
 rectangular and notched plates, somewhat larger than the 
 granules produced by the sulphate of lime. 
 
 2. i.Juu grain: an immediate cloudiness, and soon a quite good 
 
 granular deposit. Chloride of calcium produces much the 
 same reactions, but the precipitate consists chiefly of small 
 plates and octahedral crystals, which vary in size from 
 the 3,000th to the 7,000th part of an inch, Plate III, fig. 3. 
 The precipitate occasioned by the sulphate of lime is in 
 the form of oval granules, which uniformly measure about 
 the 10,000th part of an inch in their longest diameter. 
 
 3. lu.oo -o grain: very soon, a perceptible cloudiness, and in a 
 
 little time, a quite satisfactory deposit. 
 
 4. yrroiro grain, yields after a little time, a quite distinct 
 
 turbidity. 
 
 5. 5u,oou grain: after some minutes, a just perceptible opa- 
 
 lescence. 
 Fallacies. — The reaction of this reagent is much less open to 
 fallacy than that of nitrate of silver. From neutral solutions, 
 
SPECIAL CHEMICAL PROPERTIES. 159 
 
 however, sulphate of lime produces somewhat similar precipi- 
 tates with the alkaline carbonates, phosphates, and borates; but 
 from the last-mentioned, only when the solution is extremely con- 
 centrated. Chloride of calcium also occasions white precipitates 
 in solutions of these salts, and in addition, in strong solutions of 
 the alkaline citrates. But these precipitates are all readily 
 soluble in acetic acid, and may thus be distinguished from the 
 oxalate of lime. In this connection, it may be remarked that 
 even concentrated solutions of free tartaric, citric, hydrochloric, 
 and hydrocyanic acids, and of their salts, fail to yield a pre- 
 cipitate with sulphate of lime. When, therefore, this reagent 
 and nitrate of silver, produce in a suspected solution, white 
 precipitates, which in both instances are insoluble in acetic 
 acid, the results are not then open to any of the objections 
 thus far mentioned under both these tests. 
 
 Sulphate of lime also produces white precipitates, even in 
 acid solutions of lead, baryta, and strontia,, the sulphates of 
 these metals being thrown down. These precipitates, however, 
 unlike the oxalate of lime, are insoluble in nitric and hydro- 
 chloric acids; they are also insoluble in acetic acid. Chloride 
 of calcium fails to precipitate solutions of baryta and strontia; 
 but it causes in strong solutions of salts of lead, a white pre- 
 cipitate of chloride of lead, which slowly disappears on the 
 addition of water. 
 
 3. Chloride of Barium. 
 
 This reagent occasions in solutions of free oxalic acid, when 
 not too dilute, a white precipitate of oxalate of baryta, which 
 is readily soluble in nitric and hydrochloric acid, but soluble 
 with difficulty in oxalic acid, and still less soluble in acetic acid. 
 As the oxalate of baryta is soluble in hydrochloric acid, even 
 when highly diluted, the reagent fails to precipitate the whole 
 of the oxalic acid from strong solutions of the free acid: since 
 the hydrochloric acid set free by the decomposition, prevents the 
 further action of the reagent. The precipitate produced from 
 strong solutions of the acid, is usually in the form of groups 
 of bold, sharp-pointed crystalline needles. Neutral solutions of 
 
160 OXALIC ACID. 
 
 the alkaline oxalates, yield with the reagent, a white amorph- 
 ous precipitate, which soon becomes crystalline. This reaction 
 is very much more delicate than when the acid exists in its 
 free state. 
 
 1. ytTo grain of free oxalic acid, yields a quite good amorphous 
 
 precipitate, which soon becomes granular, and in a little 
 time crystalline, forming in most instances bold dumb- 
 bells, and needles, Plate III, fig. 4. If nitrate of bai-yta 
 be employed as the reagent, the precipitate is usually in 
 the form of small octahedral crystals. 
 
 2. i-,ooo grain : after a few moments, the mixture becomes 
 
 turbid, and in a little time, yields a good deposit of 
 crystalline needles, and granules. 
 
 3. sToXo grain: on stirring the mixture with a glass rod, it yields, 
 
 after some time, a quite distinct deposit of granules and 
 needles, which under the microscope are quite satisfactory. 
 Fallacies. — Chloride of barium also produces in solutions of 
 free sulphuric acid and of sulphates, a white precipitate of 
 sulphate of baryta, which, however, differs from the oxalic acid 
 precipitate, in regard to its form, and in being insoluble in 
 Strong nitric acid. In neutral solutions, the reagent also pro- 
 duces white precipitates with the alkaline carbonates and several 
 other salts; but all these deposits, except that from sulphates, 
 are readdy soluble in acetic acid. 
 
 4. Nitrate of Strontia. 
 
 Nitrate of strontia throws down from solutions of free oxaHc 
 acid a white precipitate- of oxalate of strontia, which is very 
 sparingly soluble in acetic and oxalic acids, but freely in nitric 
 and hydrochloric acids. When the acid exists in the form of 
 an alkahne oxalate, the delicacy of the reaction of this reagent 
 is much increased. 
 
 !• TW grain of the free acid, yields an immediate precipitate, 
 and in a little time there is a very good deposit of octa- 
 hedral crystals, plates, and small granules, Plate III, fig. 5. 
 2. i.Jou grain: in a little time, granules, prisms, and octahe- 
 dral crystals. 
 
SPECIAL CHEMICAL PROPERTIES. 161 
 
 3. sTBTTo grain : in a little time, a distinct turbidity, and soon 
 
 a rather good granular precipitate. 
 
 4. To,"Vo"o grain : after a few minutes, a very distinct granular 
 
 deposit. 
 The objections to the reactions of this test, and the methods 
 of answering them, are the same as pointed out under the pre- 
 ceding reagent. 
 
 5. Acetate of Lead. 
 
 Solutions of free oxalic acid, and of its soluble salts, yield 
 
 with this reagent, a white precipitate of oxalate of lead, which 
 
 is insoluble in acetic acid, but readily soluble in nitric acid. 
 
 !• Too" grain of the free acid, yields a very copious precipitate, 
 
 consisting of a mass of crystalline needles, Plate III, fig. 6. 
 
 2. TXoo grain : a copious precipitate, which immediately begins 
 
 to crystallise. 
 
 3. 5,0^0 grain : a good deposit, which soon becomes changed 
 
 into stellate crystaUine groups. 
 
 4. 10,0 grain, yields an immediate turbidity, and soon, stel- 
 
 late crystals. 
 0- y o.ooo grain : very soon the mixture becomes opalescent, and 
 
 in a little time, yields a satisfactory granular deposit. 
 6. 4 0,000 grain : after some time, the mixture becomes slightly 
 
 turbid. 
 Fallacies. — Solutions of sulphuric acid and of sulphates, and 
 strong solutions of hydrochloric acid and of chlorides, also yield, 
 when treated by the reagent, white precipitates, which, how- 
 ever, are insoluble in strong nitric acid. The reagent also 
 produces white precipitates in neutral solutions of carbonates, 
 phosphates, and several other salts, and also with a great vari- 
 ety of organic substances. These deposits, however, at least 
 for the most part, are readily soluble in acetic acid. 
 
 The oxalic acid may be recovered in its free state from the 
 oxalate of lead, by suspending the latter in water and passing 
 through the mixture a stream of sulphuretted hydrogen gas, as 
 long as it causes any blackening of the acid compound. By 
 this means the oxalate of lead will be entirely decomposed, the 
 
 metal being precipitated as black sulphuret of lead, while the 
 
 11 
 
162 ' OXALIC ACID. 
 
 eliminated acid will remain in solution: PbO, C203 + HS = PbS + 
 HO, C2O3. On now warming the mixture, to facilitate the de- 
 position of the precipitate and expel the excess of gas added, 
 filtering, and concentrating the filtrate at a moderate tempera- 
 ture, the solution on cooling, if sufficiently concentrated, will 
 deposit the acid in its crystalline form. 
 
 The precipitate produced by the reagent from ten grains of 
 a 1,000th solution of the free acid, when washed and suspended 
 in ten grains of water, then treated with sulphuretted hydrogen, 
 and the solution filtered, wiU furnish ten grains of liquid, which 
 when examined in separate drops by aU the preceding reagents 
 wiU yield results not to be distinguished from those obtained 
 from a 1,000th solution of the pure acid. In other words, the 
 100th part of a grain of the acid, when in solution in ten grains 
 of water, may be precipitated by acetate of lead and the acid 
 recovered in its free state, without any appreciable loss. The 
 presence of organic matter may however considerably modify 
 these results. 
 
 6. Sulphate of Copper. 
 
 Sulphate of copper produces in solutions of free oxalic acid, 
 when not too dilute, a precipitate of oxalate of copper, having 
 a very Hght bluish or greenish color, the tint depending on the 
 strength of the solution. The precipitate is insoluble in acetic 
 and oxalic acids, and dissolves to a very limited extent in even 
 large excess of strong nitric acid ; it is also insoluble in salts of 
 ammonia, but dissolves readily in the pure alkali. 
 1. Yoa grain, yields a very copious flocculent precipitate. 
 ^- Too grain : after a little time, a granular' precipitate, which 
 
 for the most part floats on the surface of the mixture ; the 
 
 addition of a few drops of strong nitric acid does not cause 
 
 the granules to disappear. 
 3. rroVo grain, yields after some time, a slight precipitate,^ which 
 
 is dissolved on the addition of a drop of nitric acid. 
 Fallacies. — Sulphate of copper also produces precipitates in 
 neutral solutions of carbonates and of phosphates, and is also 
 decomposed by certain kinds of organic matter with the produc- 
 tion of a precipitate ; but aU these deposits are distinguished 
 
SEPARATION FROM ORGANIC MIXTURES. 163 
 
 from the oxalate of copper, in being readily soluble in nitric and 
 hydrochloric acids. Solutions of free sulphuric, hydrochloric, 
 tartaric, and citric acids, and of their salts, fail to be precip- 
 itated by this reagent. 
 
 Separation from Organic Mixtures. 
 
 Suspected Solutions. — When the solution contains much or- 
 ganic matter, none of the preceding tests should be applied 
 directly to the mixture, since under these conditions they are 
 all liable to produce a precipitate, even in the absence of oxalic 
 acid. If the solution is strongly acid in its reaction and con- 
 tains mechanically suspended solids, the mixture, properly diluted 
 with water if necessary, is digested at a moderate heat for fifteen 
 minutes or longer, then filtered, the filtrate concentrated to a 
 small volume, and if necessary, again filtered. 
 
 As a prehminary step, a drop of the liquid may now be 
 examined by the sulphate of copper test. If this produces a 
 faintly bluish precipitate, insoluble or nearly so, in nitric or 
 hydrochloric acid, there is little doubt of the presence of oxalic 
 acid. If the precipitate thus produced is quite copious, and the 
 liquid under examination nearly colorless, then the remaining 
 portion, after further concentration if thought best, is allowed to 
 stand in a cool place for some hours, in order that the acid, in 
 part at least, may crystallise out. Any crystals thus obtained 
 are separated from the liquid, gently washed, then dissolved in 
 a small quantity of pure water, and the solution tested in the 
 ordinary manner. On further concentrating the liquid from 
 which the crystals separated, a second crop may be obtained. 
 If the crystals deposited in these operations are highly colored, 
 they should be re-dissolved in a little warm water and purified 
 by recrystallisation before being tested. 
 
 Should, however, the preliminary examination by the copper- 
 test indicate the presence of only a minute quantity of the acid, 
 or should the liquid be highly colored, then the remaining por- 
 tion is treated with slight excess of a solution of acetate of lead, 
 by which the whole of the acid will be precipitated as oxalate of 
 lead, together with more or less organic matter. The precipitate 
 
164 OXALIC ACID. 
 
 thus produced is collected on a filter and thoroughly washed, first 
 with water acidulated with acetic acid, then with pure water. 
 The moist precipitate is then diffused in an appropriate quantity 
 of water and exposed to a stream of sulphuretted hydrogen gas 
 untU the whole of the white compound is thoroughly blackened, 
 which may require an hour or longer. By this treatment, as 
 already pointed out, any oxalate of lead present will be decom- 
 posed, the acid entering into complete solution, and the metal 
 being thrown down as sulphuret. The liquid is now separated 
 from the precipitate by filtration, and kept at a moderate temper- 
 ature until the odor of the sulphuretted gas has entirely disap- 
 peared. It is then, if colorless, examined by the usual tests ; if, 
 however, it is highly colored, any oxalic acid present, is purified 
 by crystallisation, in the manner above described, and then tested. 
 
 The methods now described, would yield equal results, 
 whether the acid existed in its uncombined state or in the 
 form of a soluble oxalate, in the original liquid; and, therefore, 
 do not serve to distinguish the state in which it was present. 
 This, however, in medico-legal investigations, is rarely a matter 
 of any importance. Should it be desired to determine this point, 
 it may be approximatively done, by evaporating the prepared 
 filtered liquid to dryness on a water-bath, and extracting the 
 residue with very strong alcohol, which wiU dissolve the free 
 acid if present as such, together with more or less foreign mat- 
 ter, but only a trace of an alkaline oxalate, nearly the whole of 
 the latter, unless present in only very minute quantity, remain- 
 ing undissolved. The filtered alcohoKc solution may now be 
 evaporated to dryness on a water-bath, the residue digested with 
 a smaU quantity of water, and the filtered liquid examined by 
 either of the above-mentioned methods. The residue remaining 
 undissolved by the alcohol, supposed to contain an alkaline oxa- 
 late, is stirred with distilled water, the solution filtered, and then 
 examined in the usual manner. 
 
 Contents of the Stomach. — If no chemical antidote has been 
 administered, the contents of the stomach are collected in a 
 porcelain dish, tested in regard to their reaction, and the inside 
 of the organ well washed with distilled water, the washings 
 being collected with the contents in the dish. The mixture, 
 
SEPARATION FROM ORGANIC MIXTURES. 165 
 
 after the addition of more water if necessary, is gently boiled 
 for about half an hour, the cooled liquid strained, the solids on 
 the strainer washed, and the united liquids filtered, then concen- 
 trated and again filtered. The liquid may now, either be evap- 
 orated to dryness, and the residue thoroughly extracted by strong 
 alcohol, as described above for suspected solutions ; or, it may 
 be treated with slight excess of acetate of lead, the precipitate 
 collected on a filter, washed with water acidulated with acetic 
 acid, and any oxalate of lead present, subsequently decomposed 
 by sulphuretted hydrogen gas. 
 
 Instead of decomposing the oxalate of lead by sulphuretted 
 hydrogen, it has been proposed to boil it for about half an hour 
 in an appropriate quantity of highly diluted sulphuric acid, by 
 which it will be resolved into insoluble sulphate of lead and free 
 oxaKc acid. The liquid is then filtered, exactly neutralised by 
 ammonia, and tested. Under these circumstances, the poison 
 would exist as oxalate of ammonia, mixed with more or less 
 sulphate of ammonia ; the latter being formed from the excess 
 of sulphuric acid employed in the decomposition of the oxalate 
 of lead. The presence of this sulphate would not interfere with 
 the reactions of the silver, sulphate of lime, and copper tests ; 
 but it would yield with the barium, strontia, and lead reagents, 
 white precipitates of the sulphates of these metals. Of these 
 two methods of efi'ecting the decomposition of the oxalate of 
 lead, the former is much to be preferred. 
 
 Should lime or magnesia have been administered as an 
 antidote, the contents of the stomach, as well as any matters 
 vomited prior to death, may have a neutral reaction, and con- 
 tain the poison in the form of an insoluble oxalate of one or 
 other of these bases. Under these circumstances, the suspected 
 matters, especially aU earthy soKds, are collected in a dish, the 
 mass made quite liquid by the addition of warm water, and 
 thoroughly stirred; any organic solids present, are then washed 
 in the liquid and removed, and the remaining solids allowed to 
 completely subside. When this has taken place, the liquid is 
 decanted, and the sohds again washed with fresh water ; they 
 are then difiiised in a small quantity of pure water, a quantity 
 of pure carbonate of potash, somewhat exceeding that of the 
 
166 OXALIC ACID. 
 
 earthy matter present, added, and the mixture boiled for about 
 half an hour, the liquid evaporated during the operation being 
 replaced by distilled water. The earthy oxalate will now be 
 changed into an insoluble carbonate, while the oxalic acid will 
 be in solution in the form of oxalate of potash. This solution, 
 after filtration, is treated with decided excess of acetic acid, and 
 the oxalic acid precipitated by a solution of acetate of lead. 
 The precipitate thus produced, is collected, washed, and de- 
 composed by sulphuretted hydrogen, in the manner already 
 described. 
 
 In case of the discovery of oxalic acid in vomited matters 
 or the contents of the stomach, it might be objected, in a medico- 
 legal investigation, that the acid was a normal constituent of 
 certain vegetable structures, some of which are sometimes used 
 as articles of food or administered medicinally. Thus, it is 
 present in common sorrel, in culinary rhubarb, or pie-plant, and 
 in the rhubarb of the shops. In these substances, however, it 
 exists only in minute quantity, and in its combined state, either 
 as oxalate of potash, or of lime. But should even only a minute 
 quantity of the poison be discovered, the symptoms and other 
 circumstances attending a case of poisoning by the acid, would 
 rarely leave any doubt whatever as to its true nature. 
 
 The Urine. — Oxalic acid, when taken either in its free or 
 combined state into the stomach, soon appears in the urine, usu- 
 ally in the form of octahedral crystals of oxalate of lime. The 
 forms of these crystals readily distinguish them from all other 
 urinary deposits ; they are very similar in form to those of the 
 oxalate of strontia, as figured in Plate III, fig. 5. These crys- 
 tals are often present in the urine at the time it is voided, but 
 more frequently they do not separate until after some hours. 
 
 For the purpose of making this examination, a small portion 
 of the liquid is gently rotated in a watch-glass, until the sedi- 
 ment collects at the bottom of the fluid, when the clear liquid 
 is decanted; the sediment is then washed in a similar manner 
 with pure water, which in its turn is decanted, and the deposit 
 examined by the microscope, under an amplification of about 
 one hundred and twenty-five diameters. If none of the crystals 
 are, thus found, and the urine is fresh, some ounces of it may be 
 
QUANTITATIVE ANALYSIS. 167 
 
 allowed to stand quietly for several hours, the clear liquid de- 
 canted, the sediment collected, washed, and examined as before. 
 
 In this connection, it must be borne in mind that these crys- 
 tals also thus occur, not only after the ingestion of certain articles 
 of food, but not unfrequently as the result of disease, and some- 
 times even without any apparent cause. In fact, we have found 
 the latter to be the case much more frequently than seems to be 
 generally supposed. 
 
 If it be desired to examine the urine for the presence of the 
 free acid or of a soluble oxalate, the liquid, after the addition of 
 a Httle acetic acid, may be evaporated to about one-fourth its 
 volume, filtered if necessary, the filtrate treated with slight 
 excess of acetate of letid, any precipitate thus produced decom- 
 posed by sulphuretted hydrogen, and the filtered solution tested 
 by the usual reagents. 
 
 Quantitative Analysis. — From pure solutions, oxalic acid 
 may be estimated with considerable accuracy, in the form of 
 oxalate of lead. The solution is treated with a httle pure acetic 
 acid, and a solution of acetate of lead added as long as a pre- 
 cipitate is produced ; when the precipitate has completely sub- 
 sided, it is collected on a filter of known weight, well washed 
 with pure water, dried at 212°, and weighed. Every one hund- 
 red parts by weight of oxalate of lead thus obtained, corre- 
 spond to 42-5 parts of crystallised oxalic acid. 
 
 If the acid has been precipitated as oxalate of lime, this is 
 thoroughly washed and dried, then exposed for a few minutes to 
 a very dull-red heat. In this last operation, the oxalate will be 
 converted into the carbonate of lime, every one hundred parts 
 of which correspond to one hundred and twenty-six parts of the 
 crystallised acid. 
 
 Section II. — Hydrocyanic Acid. 
 
 History and Composition. — This substance, also known as 
 prussic acid, is a compound of the organic radical cyanogen 
 (C2N), with the element hydrogen; and is usually represented by 
 
168 HYDROCYANIC ACID. 
 
 the symbols HCy. In its pure state, it is a colorless, volatile 
 liquid, having a peculiar odor, somewhat resembling that of 
 bitter almonds. It is one of the most powerful and rapidly 
 fatal poisons yet known ; and many of its compounds are about 
 equally poisonous. It may be obtained from various vegetable 
 substances, as bitter almonds, the kernels of peaches, plums, 
 apricots, and cherries, apple-pips, the flowers of the peach, and 
 cherry -laurel, the bark of wild cherry, and the root of mountain 
 ash. In many of these substances, however, the acid does not 
 exist as such, but is the result of the decomposition to which 
 they are subjected in its preparation. 
 
 For ordinary purposes, hydrocyanic acid is usually obtained 
 by distiUing one of its salts with dilute sulphuric or hydrochloric 
 acid. The acid of the shops, is a solution of the anhydrous 
 acid, usually in water but sometimes in alcohol, and varies in 
 strength from one to twenty-five per cent., according to the 
 directions of the pharmacopoeia followed for its preparation. 
 The United States Pharmacopoeia directs a strength of two per 
 cent, of the pure acid ; and about the same proportion is directed 
 by the British Colleges. The preparation known as Scheele's 
 acid, sometimes contains as much as five per cent, of real acid, 
 but usually its strength falls very far short of this. Of several 
 specimens of commercial acid examined, we found none to con- 
 tain over 1-5 per cent, of anhydrous acid. And one of the 
 samples, which had not before been opened after having left 
 the hands of the maniifacturer, did not contain even a trace of 
 the acid. 
 
 An aqueous solution of hydrocyanic acid, especially when 
 exposed to the light, is prone to undergo spontaneous decom- 
 position, with the formation of a brown deposit. This fact, in 
 a measure at least, accounts for the difference observed in the 
 strength of samples of the acid prepared after the same formula. 
 This decomposition is much retarded by the presence of a 
 minute quantity of a mineral acid, and for that purpose a trace 
 of sulphuric acid is frequently added to the solution. An aque- 
 ous solution of the acid, when pure, is perfectly colorless. In 
 regard to its physiological effects, hydrocyanic acid belongs to 
 the class of narcotic poisons. 
 
PHYSIOLOGICAL EFFECTS. 169 
 
 Symptoms. — These, both in respect to the time within which 
 they appear and their character, depend upon the quantity of 
 the acid taken. When taken in large quantity, it not unfre- 
 quently proves so rapidly fatal that no well-marked symptoms 
 are observed. During the act of swallowing a large dose, the 
 patient experiences a hot bitter taste, and is either immediately 
 or at most within a very few minutes, seized with complete loss 
 of muscular power and of consciousness. The respiration be- 
 comes hurried, but often convulsive, and sometimes stertorous, 
 the pulse imperceptible, the extremities cold, eyes prominent, 
 the pupils dilated, and in many instances there are convulsions. 
 
 In a case reported by Hufeland, in which a man swallowed 
 about forty grains of the pure acid, in the form of an alcoholic 
 solution, the patient immediately staggered a few steps, and 
 then fell, apparently lifeless. When seen, almost instantly 
 afterwards, by a physician, the pulse was imperceptible and 
 the respiration entirely suspended. After a short interval, the 
 man made a very forcible expiration ; the extremities became 
 cold, the eyes prominent, glistening, and insensible to light, and 
 after a few convulsive expirations he died, within five minutes 
 after the poison had been taken. 
 
 It was formerly believed that when prussic acid was taken 
 in rapidly fatal quantity, it always produced immediate insensi- 
 bility ; but this is by no means always the case. When taken 
 in such quantity, the symptoms usually appear within a very 
 few seconds, yet they have in several instances been delayed 
 sufficiently long for the patient to perform a series of voluntary 
 acts. In a case related by Dr. Sewell, a man swallowed seven 
 drachms of Scheele's preparation of the acid, believed to con- 
 tain about twenty-one grains of the anhydrous poison, after 
 which he walked to the door of his room, unlocked it, called for 
 assistance, then walked to a sofa, and stretched himself upon 
 it ; in a very little time after this, he was found in an insensible 
 state, with stertorous breathing, and soon died. (Boston Med. 
 and Surg. Jour., xxxvii, p. 322.) 
 
 The following remarkable instance is quoted by Dr. Taylor 
 (On Poisons, p. 646). A gentleman, aged forty-four years, 
 swallowed, it was supposed, half an ounce of prussic acid 
 
170 HYDROCYANIC ACID. 
 
 (strength not stated). He then walked ten paces to the top of 
 a flight of stairs, descended the stairs, seventeen in number, 
 and went to a druggist's shop at forty-five paces' distance, where 
 he had previously bought the poison, entered the shop, and 
 said, in his usual tone of voice, " I want some more of that 
 prussic acid !" He then became insensible, and died in from 
 five to ten' minutes after taking the poison. 
 
 When the dose is not sufficiently large to produce rapid 
 insensibility, the first symptoms usually experienced are giddi- 
 ness and a sense of great weakness ; these effects are soon suc- 
 ceeded by irritation in the throat, an increased flow of saliva, 
 nausea, difficult and spasmodic respiration, and loss of voluntary 
 motion ; the pulse becomes small or imperceptible, the face livid, 
 and the eyes glaring, the pupils generally being dilated. These 
 cases are frequently attended with tetanic convulsions. 
 
 The following case of recovery is quoted in detail by Dr. 
 Stille (Mat. Med., ii, p. 210). A French physician swallowed 
 a dessert-spoonful of the medicinal acid, prepared by a chemist 
 of Paris. He almost immediately afterwards fell down as if 
 struck by lightning. Among the symptoms observed, were loss 
 of consciousness and sensibility ; trismus ; a constantly increas- 
 ing dyspncea ; cold extremities ; a noisy and rattling respiration; 
 the characteristic odor of the acid upon the breath ; distortion 
 of the mouth ; and a thready pulse. The face was swollen and 
 dusky, and the pupils fixed and dilated. The trismus increased, 
 and was soon accompanied by opisthotonos. At the end of an 
 hour, a violent convulsion occurred, the whole trunk grew stiff', 
 and the arms were twisted outwards. After two hours passed 
 in this condition, the patient began to regain his consciousness, 
 and in several hours afterwards, he was able to walli without 
 assistance ; but it was a fortnight before he entirely recovered. 
 
 In a non-fatal case reported by Mr. W. H. Bumam, in 
 which a dose containing 'i- 4: grains of the anhydrous acid was 
 taken by mistake, insensibility did not occur until two minutes 
 after the poison had been swallowed. In the mean time, how- 
 ever, the patient, having almost immediately discovered his 
 mistake, took as an antidote half an ounce of aromatic spirits 
 of ammonia, with a little wafer ; and he told what had occurred : 
 
PHYSIOLOGICAL EFFECTS. 171 
 
 lie spoke hurriedly, and breathed deeply. A solution of sul- 
 phate of iron was then administered. The respiration became 
 deeper and slower. In four minutes after the poison was taken, 
 the cold douche was freely employed, and an additional quan- 
 tity of the iron solution with spirits of ammonia administered. 
 Vomiting took place ; and there was a slight convulsive shudder. 
 In twenty minutes, the patient began to exhibit signs of return- 
 ing consciousness ; and in about fifteen minutes later, he was 
 able to walk up stairs to bed. (Brit, and For. Med.-Chir. Rev., 
 April, 1854.) In a case of recovery reported by Mr. Garson, 
 in which a teaspoonful of the acid of unknown strength had 
 been taken, the symptoms were delayed for about ^feew minutes. 
 The individual was then found in a state of insensibility, and 
 this continued for about four hours, although active remedies 
 were employed. This is the most protracted case, in regard to 
 the appearance of the symptoms, yet recorded. 
 
 Several instances are reported, in which the inhalation of 
 the diluted vapor of hydrocyanic acid caused most alarming 
 symptoms ; and Dr. Christison quotes a case in which the liquid 
 acid applied to a wound in the hand, caused death in an hour 
 afterwards. 
 
 Hydrocyanic acid is also equally poisonous, with the pro- 
 duction of similar symptoms, when taken into the system in the 
 form of an alkaline cyanide. Since the introduction of cyanide 
 of potassium into the arts for photographic and other purposes, 
 numerous instances of poisoning by it have occurred. In a 
 case of poisoning by this salt related by Dr. Schauenstein, of 
 Vienna, occurring in a young man, death took place almost 
 instantly, without any striking symptoms. In another case, 
 reported by the same writer, strong tetanic spasms came on 
 directly after the poison had been taken, and death ensued in 
 less than an hour. (Amer. Jour. Med. Sci., Jan., 1860, p. 279.) 
 In a case in which we were consulted in 1864, a man took, 
 with suicidal intent, about sixteen grains of the salt in solution ; 
 immediately after swallowing the poison, he walked about six 
 steps, then fell insensible, and death ensued in about five minutes. 
 
 Period when Fatal. — The fatal period, in poisoning by hy- 
 drocyanic acid, is subject to considerable variation ; yet it is 
 
172 HYDROCYANIC ACID. 
 
 extremely limited when compared with that of the action of 
 most other poisons. Several instances are recorded in which 
 death took place in from five to ten minutes, and it has occurred 
 in two minutes, and, perhaps, even within a shorter period. 
 On the other hand, death has been delayed for nearly an hour, 
 even when the quantity of poison taken was sufficiently great 
 to produce almost inimediate insensibility. In fatal cases, how- 
 ever, Kfe is rarely prolonged beyond half an hour : those who 
 survive this period usually entirely recover. In an accident 
 that occurred in one of the hospitals of Paris, by which seven 
 epileptic patients -were fatally poisoned, by equal quantities of 
 hydrocyanic acid, the fatal period varied from fifteen to forty- 
 five minutes. 
 
 Fatal Quantity. — That similar quantities of prussic acid do 
 not always produce the same result, is well illustrated in the 
 instance of the Parisian epileptics just mentioned. The quan- 
 tity of the poison taken by each of these patients is stated by 
 most toxicological writers, on the authority of Orfila, to have 
 been equivalent to about two-thirds of a grain of the anhydrous 
 acid ; but it appears from more recent statements (Braithwaite's 
 Eetrospect, xii, p. 125), that the quantity actually taken by 
 each, was equivalent to five grains and a half of the real acid. 
 In a case reported by Mr. Hicks, a solution containing nine- 
 tenths of a grain of the pure acid, proved fatal to a healthy 
 woman, aged twenty-two years, in from fifteen to twenty min- 
 utes. This seems to be the smallest fatal quantity yet recorded. 
 Smaller quantities have, hqwever, in several instances produced 
 most dangerous symptoms. 
 
 On the other hand, Mr. Bishop has related a case in which 
 a man entirely recovered, after having taken a dose, in the 
 form of forty minims of a solution, containing one grain and a 
 third of anhydrous prussic acid (London Lancet, Sept., 1845, 
 p. 315). In this case, the patient, according to his own ac- 
 count, remained sensible for at least two minutes after taking 
 the poison. When first seen by Mr. Bishop, about ten minutes 
 after the occurrence, he was senseless, the countenance ghastly 
 pale, face swollen and covered with perspiration, the respiration 
 slow and labored, the eyes fixed and glazed, the pupils dilated. 
 
ANTIDOTES. 173 
 
 and the whole body in a rigid state. The treatment consisted 
 in cold affusion, ammonia, emetics, and bleeding. So also, Dr. 
 Christison has recently reported a case, in which a gentleman 
 recovered after having taken a solution equivalent to between 
 a grain and a half and two grains of the anhydrous acid. And 
 in a case already cited, that reported by Mr. Burnam, recovery 
 followed even after 2-4 grains of the pure acid, in solution, had 
 been swallowed. In this case, however, as well as in that 
 reported by Dr. Christison, active remedies were almost imme- 
 diately employed. 
 
 Treatment. — On account of the rapid action of hydrocy- 
 anic acid, when taken in poisonous quantity, it rarely happens 
 that treatment can be resorted to in time to be of much service. 
 The remedies consist chiefly in the exhibition of stimulants ; 
 but certain chemical antidotes have also been advised. 
 
 The exhibition of the vajpor of ammonia has been highly 
 recommended, and several instances are reported in which its 
 use was attended with great advantage. It has also been pro- 
 posed to administer a solution of ammonia, diluted with water ; 
 but in this form, according to Orfila, it is of no service. Chlo- 
 rine, administered either in the form of vapor or taken inter- 
 nally, has also been strongly advised. It may be used in the 
 form of a weak solution of hypochlorite of lime or of the cor- 
 responding salt of soda. The gas is readily obtained by acting 
 on either of these salts with diluted hydrochloric or acetic acid. 
 From experiments on inferior animals, Orfila was led to believe 
 that chlorine was the most efiicient antidote yet proposed. It 
 need hardly be added, that great caution should be exercised 
 in its administration. 
 
 Cold affusion, first recommended by Herbst, has perhaps on 
 the whole been found the most efiicient remedy hitherto em- 
 ployed in the human subject. Its use should be accompanied 
 by the exhibition of the vapor of chlorine or ammonia. In 
 several instances of recovery, in which this treatment was em- 
 ployed, it was apparently the^ means of averting death. Arti- 
 ficial respiration was strongly insisted on by the late Dr. 
 Pereira. He successfully employed it in experiments on ani- 
 mals. Stimulating injections, as well as blood-letting, have also 
 
-174 HYDROCYANIC ACID. 
 
 been advised. The latter should be resorted to with great 
 caution. 
 
 As a chemical antidote, it has been suggested, by Messrs. 
 Smith, of Edinburgh, to administer a solution of a mixture of 
 the sulphates of the protoxide and sesquioxide of iron, quickly 
 followed by a solution of carbonate of potash. A mixture of 
 this kind produces with hydrocyanic acid, Prussian-blue, which 
 is inert, being insoluble. In experiments on animals, this treat- 
 ment was quite successful. Even if this antidote be at hand, 
 it should never be relied on to the exclusion of stimulants and 
 cold affusion. 
 
 Post-mortem Appearances. — These will, of course, de- 
 pend somewhat on the length of time the individual survived 
 after taking the poison, and also the period that has elapsed 
 since death. The face is usually pale, but often livid, the 
 eyes glistening and staring, the lips blue, the jaws closed, 
 and the extremities soon become rigid. The blood through- 
 out the body is fluid, and generally of a dark or bluish color; 
 the venous system turgid ; the arteries nearly empty ; the 
 liver, and in some instances the lungs, much congested. The 
 stomach, other than so far as cadaveric changes have taken 
 place, is generally natural. It need hardly be observed, that 
 neither of these appearances is peculiar to death from hydro- 
 cyanic acid. 
 
 One of the most striking characters in death from this 
 poison, is the exhalation of the peculiar odor of the acid. This 
 is sometimes emitted from the corpse, even before any dissec- 
 tions are made, and, at least in recent cases, is nearly always 
 exhaled when the stomach or thoracic cavity is opened; and it 
 is often detected in the blood throughout the body. As, how- 
 ever, hydrocyanic acid is very volatile, and also readily under- 
 goes decomposition, it may in a little time, so far disappear 
 from the body, that its odor can no longer be recognised. 
 Moreover, the odor of the acid is liable to be masked by the 
 presence of other odors. In a singular case related by Prof. 
 Casper, however, in which a woman had poisoned herself with 
 a mixture of prussic acid and a variety of essential oils, and 
 the body diffused a sweet odor, on opening the stomach such a 
 
CHEMICAL PROPERTIES. 175 
 
 powerful aroma of bitter almonds came forth as almost to stupefy 
 every one present. In several reported instances in which this 
 character was not observed in the stomach, a subsequent chem- 
 ical analysis revealed the presence of very notable quantities 
 of the poison, in one case even so much as one grain of the 
 anhydrous acid. In Dr. Sewell's case, in which seven drachms 
 of the medicinal acid had been taken, he failed to detect the 
 odor of the poison upon applying his nose to the mouth of the 
 deceased, very soon after death. 
 
 In the case reported by Hufeland, already mentioned, the 
 body exhaled the odor of the acid on the day following death. 
 The countenance was pale and composed, the eyes glistening, 
 spine and neck stiff, and the back livid. The blood was fluid, 
 bluish in color, and throughout the body emitted a very strong 
 odor of the poison. The vessels of the brain, as well as the 
 liver and lungs, were gorged with blood; the arteries empty, 
 the veins distended, and the mucous membrane of the stomach 
 and intestines reddened. 
 
 In the cases of the seven Parisian epileptics, no odor of the 
 poison was perceived in any part of the body, twenty-four 
 hours after death. The lips, face, and head were bloated and 
 of a violet color; the back livid; frothy blood escaped from 
 the mouth and nostrils; the eyes were closed, and the body 
 rigid. The stomach was highly injected; the liver, spleen, and 
 kidneys much gorged with black blood; the arteries empty, 
 and the veins turgid. In Mr. Hicks' case, in which only nine- 
 tenths of a grain of the acid was taken, the odor of the poison 
 was plainly perceived on opening the chest, and was also 
 strongly emitted from the contents of the stomach, although the 
 examination was not made until ninety hours after death. 
 
 Chemical Peopeeties. 
 
 General Chemical Nature. — Anhydrous hydrocyanic acid 
 (H Cy), is a colorless, very volatile, inflammable liquid, of a 
 peculiar odor. It readily mixes in aU proportions with alcohol 
 and water. The pure acid has a specific gravity of 0-706, and 
 boils at 80° F., yielding a combustible vapor. 
 
176 HYDROCYANIC ACID. 
 
 The medicinal acid is usually obtained by distilling, at a mod- 
 erate heat, a solution of ferrocyanide of potassium (KzFeCya), 
 with dilute sulphuric acid, and collecting the product in water, 
 contained in a cooled receiver. The reaction is as follows : 
 
 2 K^Fe Cj,+ 6 HO, S03= K Cy, 2 Fe Cy + 3 KO, 2 SO3+ 3 HO + 
 
 3 H Cy. The commercial acid, when pure, has a very feeble 
 acid reaction, and a density varying with its strength; when it 
 contains about three per cent, of the acid, its specific gravity 
 is about 0-998. 
 
 When hydrocyanic acid is brought in contact with a solu- 
 tion of an alkaline oxide, both the acid and alkaline compound 
 undergo decomposition, with the formation of a salt, or cyanide, 
 of the metal, and the production of water, thus KO + H Cy = 
 KCy + HO. These salts are freely soluble in water; they are 
 readily decomposed by acids, with the evolution of free hydro- 
 cyanic acid. When exposed to the air, either in their solid 
 state or in solution, they slowly absorb carbonic acid, and thus 
 become changed into carbonates, the eliminated prussic acid 
 being dissipated in the form of vapor. The cyanides of the 
 metals proper, unlike those of the alkalies, are for the most 
 part insoluble in water; but many of them are freely soluble 
 in a solution of an alkaline cyanide, with the formation of a 
 double salt. 
 
 Special Chemical Propeeties. — It has been claimed by 
 several toxicological writers, that the odor of hydrocyanic acid 
 serves to detect the presence of smaller quantities of the poison 
 than can be recognised by any of the chemical tests; but this 
 is an error, even in regard to the vapor from perfectly pure 
 solutions of the acid. Nevertheless, under certain conditions, 
 extremely minute quantities of the acid may thus be recog- 
 nised. We have found in repeated experiments, that when ten 
 grains of a 50,000th solution of the pure acid (= 5 oV u grain 
 H Cy) are enclosed for some time in a small test-tube, and the 
 tube then opened, the peculiar odor of the poison is sufficiently 
 marked to be described by persons entirely ignorant of the true 
 nature of the solution. With a similar quantity of a 100,000th 
 solution, an odor is perceptible, but its peculiar character is 
 lost. It need hardly be repeated, that the odor from even 
 
SILVER TEST. 177 
 
 strong solutions of the poison, may be entirely disguised by the 
 presence of other odors. 
 
 There are but few chemical tests to which we resort for the 
 detection of hydrocyanic acid, but these are so characteristic 
 and delicate in their reactions, as to leave nothing more to be 
 desired in this respect. Moreover, they are equally applicable 
 for the detection of the vapor of the poison. In the following 
 examination of these tests, the fractions employed indicate the 
 quantity of anhydrous prussic acid in solution in one grain of 
 pure water. The results, unless otherwise stated, refer to the 
 behavior of one grain of the solution. 
 
 1. Nitrate of Silver. 
 
 Nitrate of silver throws down from solutions of free hydro- 
 cyanic acid, and of soluble cyanides, a white amorphous pre- 
 cipitate of cyanide of silver (Ag Cy), which is insoluble in the 
 fixed caustic alkalies, and only sparingly soluble in ammonia, 
 but readily soluble in the alkaline cyanides. Cold nitric acid 
 fails to dissolve it, but it is soluble in the hot concentrated acid; 
 hydrochloric acid decomposes it with the formation of chloride 
 of silver and the evolution of hydrocyanic acid. 
 
 1. yj-Q grain of hydrocyanic acid, in one grain of water, yields 
 
 a very copious precipitate, which does not entirely disap- 
 pear when the mixture is heated with several drops of 
 strong nitric acid. 
 
 2. i.Joo grain, yields a copious precipitate, which readily dis- 
 
 solves on the addition of a drop of strong ammonia; but 
 dissolves with difficulty, in the mixture, in several drops 
 of warm nitric acid. 
 
 3. 10,0 grain: a quite good flocculent precipitate. 
 
 4. 2 5 ,^0 o T) grain, yields no immediate precipitate, but in a very 
 
 little time the mixture becomes turbid, and soon there is a 
 very satisfactory deposit. 
 
 5. 5 0,000 grain: after a little time, a very distinct opalescence, 
 
 and soon a very perceptible deposit. 
 
 6. 10 0^00 grain: in a few minutes, the mixture becomes very 
 
 distinctly turbid. 
 
 12 
 
178 HYDROCYANIC ACID. 
 
 Fallacies. — Nitrate of silver also produces white precipitates 
 in solutions of free hydrochloric acid, of chlorides, carbonates, 
 phosphates, tartrates, and some other salts, and also with various 
 kinds of organic matter. These precipitates, however, except 
 that from chlorine, are readily soluble in strong nitric acid, in 
 which they differ from the cyanide compound. The chloride 
 of silver readily darkens when exposed to light, whereas the 
 cyanide remains unchanged in color; again, the former salt is 
 readily soluble in ammonia, whilst the latter is not, unless pres- 
 ent only in very minute quantity. Tolerably strong solutions 
 of iodides and bromides, and of their free acids, yield with 
 nitrate of silver yellowish-white precipitates ; from dilute solu- 
 tions, however, these precipitates, in regard to color, might 
 readily be mistaken for the cyanide compound, especially when 
 they are obtained from organic mixtures : like the cyanide 
 deposit, they are nearly insoluble, or dissolve with difficulty, in 
 cold nitric acid. 
 
 The cyanide of silver is readily distinguished from aU other 
 precipitates produced by this reagent, in that when thoroughly 
 dried and heated in a narrow reduction-tube, it undergoes de- 
 composition with the evolution of cyanogen gas, which, when 
 ignited, burns with a rose-colored flame. If this decomposition 
 be effected in a small tube, which after the introduction of the 
 dried cyanide has been drawn out into a very narrow capillary 
 neck, beginning something less than an inch above the cyanide 
 compound, the 100th part of a grain of the salt will yield sat- 
 isfactory results. For the success of this experiment, it is 
 essential that the cyanide be thoroughly dried before being 
 introduced into the tube. 
 
 Vapor of Hydrocyanic Acid. — When the vapor of prussic 
 acid is received on a drop of nitrate of silver solution, the latter 
 becomes coated with a white film of cyanide of silver, which, 
 especially from dilute solutions of the acid, is crystalline, and 
 most abundant along the margin of the drop. In its behavior 
 with reagents, this deposit has the properties already de- 
 scribed. This test may be applied by placing a drop of the 
 acid solution in a watch-glass, and covering the latter with 
 a similar, inverted glass, containing a small drop of the silver 
 
SILVER TEST. 179 
 
 solution. By this method, one grain of the acid solution yields 
 
 as follows : 
 
 !• Too grain of hydrocyanic acid, in one grain of water: an 
 immediate cloudiness is observed in the silver solution, 
 and in a very little time there is a quite copious white 
 deposit. Under the microscope, the deposit has the ap- 
 pearance of an amorphous mass, but if broken up, with 
 the point of a needle, it will be found to consist of very 
 small but distinct crystals. If the watch-glass containing 
 the poison be first placed on the stage of the microscope 
 ^ and then covered by the glass containing the silver solu- 
 tion, the formation of the crystals may, at least for a time, 
 be observed. 
 
 2. 1 , J grain: an immediate cloudiness appears in the reagent 
 
 solution, and soon there is a quite good, white film. If its 
 formation be observed under the microscope, the crystals 
 will be found to form more slowly and become somewhat 
 larger than in 1. 
 
 3. io.ooo grain: in a little time a cloudiness appears, and after 
 
 a few minutes there is a quite good deposit, which con- 
 sists principally of irregular crystals, varying from the 
 1,000th to the 2,000th part of an inch in length, of 
 the forms illustrated in Plate IV, fig. 1. Usually, small 
 granules, prisms, and needles form along the margin of 
 the drop. 
 
 4. 2Tro"oT) grain : after a little time the margin of the silver solu- 
 
 tion becomes white, and soon there is a good crystalline 
 deposit. 
 
 5. ToToWo grain : when a very small drop of the reagent solu- 
 
 tion is employed, crystals appear in less than two minutes, 
 and before long there is a very satisfactory deposit. 
 6- rooVoTj grain: after a few minutes crystals can be seen with 
 the microscope, and after some minutes . they are quite 
 evident to the naked eye. The deposit is confined to the 
 margin of the drop, and chiefly consists of granules, sVnall 
 prisms and needles, Plate IV, fig. 2. So far' as the evi- 
 dence of the presence of hydrocyanic acid is concerned, 
 this quantity furnishes as unequivocal results as any larger 
 
180 HYDROCYANIC ACID. 
 
 amount. The formation of the deposit is much facilitated 
 by applying the warmth of the hand to the watch-glass 
 containing the acid solution. 
 It need hardly be observed that if the silver solution be- 
 comes nearly dry from evaporation, crystals of nitrate of silver 
 may separate; but these have a very different form from those 
 of the cyanide, and moreover they immediately disappear on 
 the addition of a very small drop of water, whilst the cyanide 
 crystals are almost wholly insoluble in this liquid. 
 
 The vapors of chlorine, bromine, and iodine, and of their 
 hydrogen acids, also yield white or nearly white films with a 
 solution of nitrate of silver. The deposits from all these sub- 
 stances, however, are amorphous; whereas the cyanide com- 
 pound is always crystalline, even when obtained from complex 
 organic mixtures of the acid, provided sulphuretted hydrogen 
 or some other gaseous 'substance which also produces a deposit, 
 is not present. The odor of these substances, as well as that 
 of hydrocyanic acid, would generally suffice to determine the 
 true nature of the film produced by these various vapors, even 
 without the aid of the microscope. The deposits produced by 
 the vapors of bromine and iodine, have a faint yellowish-white 
 color. It may be remarked that the vapors of chlorine and of 
 hydrochloric acid, generally cause the dispersion of the silver 
 solution, so that it trickles down the inside of the inverted 
 watch-glass; and the films, produced by them are quite thin, 
 even when occasioned by the pure gases. 
 
 2. Iron Test. 
 
 When a solution of free hydrocyanic acid is treated with a 
 solution of caustic potash or soda, and then with a solution of 
 sulphate of iron which has been exposed to the air and contains 
 some persulphate of the sesquioxide of iron, it yields a precipi- 
 tate of Prussian-blue (FciSFeCya), mixed with more or less 
 protoxide and sesquioxide of iron : this mixture may have either 
 a yellowish-brown, greenish, or bluish color, the hue depending 
 upon the relative quantities of the iron compounds present. 
 On treating this mixture with a few drops of hydrochloric or 
 
IRON TEST. 181 
 
 sulphuric acid, the oxides of iron dissolve, while the Prussian- 
 blue remains in the form of a deep blue deposit, it being insolu- 
 ble in the acid. Should the hydrocyanic acid already exist in 
 the form of an allcaline cyanide, the addition of the potash or 
 soda solution should be omitted. In a solution of free prussic 
 acid, the iron compounds alone produce no change. 
 
 The object of the addition of the free alkali in the above 
 process, is to convert the free hydrocyanic acid into an alkaline 
 cyanide. When this salt is then treated with the sulphates of 
 the prot- and sesqui-oxides of iron, a double decomposition takes 
 place, in which the alkaline cyanide becomes changed into sul- 
 phate of potash, and the iron sulphates into proto- and sesqui- 
 cyanides of iron, thus: 9 K Cy + 3 FeO, SO3+ 2 FezO,; 3S03 = 
 9 KO, SO3 + 3 Fe Cy + 2 Fe^ Cya ; the elements of the iron cyan- 
 ides then coalesce to form Prussian-blue (3 Fe Cy + 2 Fcj Cy, = 
 FciSFeCya). It is thus obvious that the presence of both the 
 iron oxides are necessary for the production of the blue com- 
 pound. The oxides of iron precipitated by any excess of 
 potash employed, are dissolved by the hydrochloric or suL- 
 phuric acid added, as chlorides or sulphates of iron. 
 
 In very dfiute solutions of hydrocyanic acid, the test fails 
 to produce an immediate precipitate ; but the liquid, after the 
 addition of the mineral acid, immediately acquires a greenish 
 color, and after a time deposits flakes of the blue compound. 
 Such solutions also require a proper adjustment of the potash 
 and iron solutions. A large excess of potash wiU decompose 
 the Prussian-blue, while a similar excess of the iron mixture, 
 produces with hydrochloric acid, a yellow liquid which may 
 hold in solution a small quantity of the blue compound. When, 
 therefore, the addition of the chlorine acid produces a yellow 
 solution from which no Prussian-blue separates, even after a 
 time, the experiment should be repeated with a less quantity of 
 the iron solution, before pronouncing hydrocyanic acid entirely 
 absent. There is no difficulty in the application of the test, 
 except in very dilute solutions of the poison. In no case, 
 should any inference be drawn from the color of the precipitate 
 prior to the addition of the mineral acid, since it may have a 
 bluish color, even in the absence of prussic acid. 
 
182 HYDROCYANIC ACID. 
 
 One grain of a hydrocyanic acid solution, when treated as 
 above, yields the following results : 
 
 !• To"o grain of the pure acid, yields a very copious deposit of 
 Prussian-blue. 
 
 2. 1,000 grain : a very good deposit, 
 
 3. 5,000 grain : a greenish-blue, flocculent precipitate, and a 
 
 greenish solution ; after a time, the deposit increases in 
 quantity and acquires a deeper blue color. Solutions 
 dilute as this, especially when only a single drop is op- 
 erated upon, require a proper adjustment of the reagent 
 solutions : when these are very strong, only a very small 
 drop of each should be employed. 
 
 4. To7d"ro grain : with a very small quantity of the potash and iron 
 
 solutions, yields a quite perceptible greenish-blue, flocculent 
 precipitate, with a greenish solution ; after the mixture has 
 stood some little time, the result is perfectly satisfactory. 
 5- 2^57ffo'o grain, yields just perceptible greenish flakes, and 
 after a few hours, a quite distinct deposit, which when 
 examined by a hand-lens, has a well-marked blue color. 
 The production of a blue precipitate, insoluble in hydro- 
 chloric acid, by this test, is perfectly characteristic of hydro- 
 cyanic acid, or at least of a cyanide. At the same time, the 
 reaction is not interfered with by any substance at all likely to 
 be met with in medico-legal investigations. 
 
 Vapor of Hydrocyanic Acid. — In the application of this test 
 for the detection of the vapor of the poison, the vapor is 
 received for some minutes on a drop of potash solution, by 
 which it will be absorbed as cyanide of potassium, without how- 
 ever any visible change ; the solution is then treated with the 
 iron mixture and hydrochloric acid, in the manner above de- 
 scribed. The vapor from one grain of a 5,000th solution of the 
 poison, will, when the manipulations are conducted with great 
 care, yield quite satisfactory results. This, however, is about 
 the limit of the vapor reaction. 
 
 This method may be employed to confirm the nature of the 
 cyanide of silver, produced by the preceding reagent. For 
 this purpose the washed deposit, placed in a watch-glass, is 
 treated with a drop of hydrochloric acid, and the vapor of the 
 
SULPHUR TEST. 183 
 
 hydrocyanic acid thus ehminated, absorbed by a drop of potash 
 solution, in the manner just pointed out. By this process, the 
 true nature of a much less quantity of the silver precipitate may 
 be fully established than by the method of reduction, heretofore 
 described. 
 
 3. Sulphur Test. 
 
 When a solution of free hydrocyanic acid or of an alkaline 
 cyanide is treated with a solution of yellow sulphuret of ammo- 
 nium, and the mixture gently heated, it gives rise to sulpho- 
 cyanide of ammonium, which when treated with a persalt of 
 iron, yields a deep blood-red solution of sulphocyanide of iron. 
 This reaction was first pointed out in 1847, by Prof Liebig. 
 
 In applying this test, a few drops of the prussic acid solu- 
 tion, placed in a small white dish or watch-glass, are treated 
 with a drop of the sulphuret of ammonium, and the mixture 
 evaporated at a moderate temperature, on a water-bath, to near 
 dryness. Should the residue have a yellow color, it is moist- 
 ened with a drop of water and again evaporated. The cooled 
 residue — consisting of sulphocyanide of ammonium, often in its 
 crystalline state, and a white film of sulphur — is then treated 
 with a drop of a colorless solution of persulphate of iron or 
 of sesquichloride of iron, when the mixture wiU immediately 
 assume, unless very dilute, a very deep blood-red color. If the 
 excess of sulphuret of ammonium added has not been entirely 
 decomposed or volatilised, the iron reagent wiU produce a black 
 precipitate of sulphuret of iron ; this however is readily dis- 
 solved by a drop of dilute hydrochloric acid, without interfering 
 with the red color of the mixture, unless it is very feeble. 
 !■ Too grain of hydrocyanic acid, when treated as above, yields 
 a beautiful blood-red solution. 
 
 2. 1,000 grain, yields an orange-colored mixture. 
 
 3. 1 .0 o 'o grain : the final solution has a very satisfactory light- 
 
 orange hue. 
 
 4. 2 5,000 grain, yields a mixture having a distinct reddish tint. 
 
 The color of this mixture is quite well marked when com- 
 pared with that of the reagents alone. 
 
 5. 5 0,0 grain, yields a just perceptible coloration. 
 
184 HYDROCYANIC ACID. 
 
 The red color produced by this test is immediately dis- 
 charged by corrosive sublimate, and by nitric acid ; but it is 
 unaifected by even very large excess of strong hydrochloric 
 acid, except from very dilute solutions, when it is readily 
 destroyed by an excess of this acid. It is also discharged, 
 to a faint reddish hue, by an alkaline acetate, but immedi- 
 ately restored upon the addition of hydrochloric acid; ammonia 
 causes it to disappear, with the precipitation of sesquioxide 
 of iron. 
 
 Fallacies. — Persalts of iron also strike a deep blood-red color 
 with solutions of meconic acid. This color, however, is not 
 discharged by corrosive sublimate, nor is it affected by an alka- 
 line acetate, and it is readily changed to yellow or reddish- 
 yellow, by an excess of hydrochloric acid. The reagent also 
 changes very strong solutions of the alkaline acetates to a deep 
 dark-red color, due to the formation of acetate of sesquioxide 
 of iron ; this color, however, is immediately discharged to a 
 faint yellow tint, by even a very small quantity of hydrochloric 
 acid. In this connection, it may be remarked that both meconic 
 acid and the aUcaline acetates are destitute of odor. 
 
 The objections just mentioned are the only ones that can 
 reasonably be urged against the sulphur test, and they are 
 readily answered. When, therefore, a suspected solution yields 
 with the test a strong red color, unaffected by large excess of 
 hydrochloric acid, there is no doubt of the presence of a sul- 
 phocyanide ; yet, should the color be only faint, its disappear- 
 ance, on the addition of the acid, would not prove the entire 
 absence of the poison. 
 
 Vapor of Hydrocyanic Acid. — The sulphur test may also 
 be applied for the detection of the vapor of the acid, as first 
 suggested by Dr. A. Taylor. For this purpose, a drop of the 
 sulphuret of ammonium solution, contained in an inverted watch- 
 glass, is exposed to the evolved vapor for some minutes, and 
 then examined in the manner above described. 
 
 The vapor evolved from the 10,000th part of a grain of 
 prussic acid, in one grain of water, will after this method, pro- 
 viding the ammonium solution has been exposed to the vapor 
 from ten to fifteen minutes, yield a very distinct coloration ; 
 
RELATIVE VALUE OF TESTS. 185 
 
 but the result could hardly be claimed to be satisfactory. It 
 need hardly be added, that when the sulphur test is appKed in 
 this manner, it is free from the fallacies that hold in its direct 
 application to a suspected liquid. 
 
 The sulphur test may also be employed to confirm the pre- 
 cipitate produced by the silver reagent. For this purpose, the 
 washed precipitate is treated with a few drops of sulphuret of 
 ammonium, and the mixture evaporated, at a gentle tempera- 
 ture, to dryness. In this operation, the cyanide of silver will 
 be decomposed by the ammonium compound, with the formation 
 of sulphuret of silver and sulphocyanide of ammonium. On 
 now treating the dry residue with a little water, the ammonium 
 salt will dissolve, and the solution, after filtration and concen- 
 tration, yield the usual blood-red _ color when treated with a 
 persalt of iron. 
 
 So also, this test may be applied to the vapor evolved, when 
 the cyanide of silver is decomposed by a drop of strong hydro- 
 chloric acid. 
 
 Eelative Delicacy of the foregoing Tests. — In regard 
 to the relative value, in this respect, of the Silver and Iron 
 tests, it may be observed, that when they are applied to the 
 vapor of the poison, the former is much the most dehcate, while 
 for solutions, the latter is much the most susceptible. It is 
 true, that the silver test will produce a precipitate with a much 
 less quantity of the poison than the iron test will reveal; yet 
 the silver deposit cannot in itself be regarded as peculiar, mitil 
 it yields an inflammable gas when heated in a reduction-tube, 
 for which purpose it requires, with the greatest care, the pre- 
 cipitate corresponding to the 500th part of a grain of the poison, 
 and even the deposit from this single quantity could by no 
 means be collected and confirmed: but the iron test produces a 
 characteristic reaction with one grain of a 10,000th solution of 
 the poison. 
 
 On the other hand, when applied to the vapor of hydro- 
 cyanic acid, the iron reaction has its limit with about the 
 5,000th part of a grain of the acid, whilst the silver test yields 
 a satisfactory result with the 100,000th part of a grain, in one 
 
186 HYDROCYANIC ACID. 
 
 grain of water. In other words, for solutions, the iron test is 
 about twenty times more delicate than the silver test, while for 
 the vapor of the poison, the silver reaction is about twenty 
 times more delicate than the iron test. 
 
 In regard to the Sulphur test, when applied to solutions of 
 the acid, it is somewhat more delicate than the iron reaction, 
 and so also in regard to the detection of the vapor, but in the 
 latter respect very much inferior to the silver method. From a 
 review of these tests, it is obvious that should a suspected solu- 
 tion fail to yield a precipitate with nitrate of silver, it would 
 be useless to apply either of the other tests; yet it should be 
 remembered that a solution which only yields a faint reaction 
 with the silver reagent, may evolve a vapor that will yield with 
 it very satisfactory results. 
 
 The comparative value of these tests may be approxima- 
 tively exhibited as follows: 
 
 Silver test, with Solutions, ttJtj grain; with Vapor, Trny^TnTC grain. 
 Iron test, " " tjsM^ grain; " " -g^^ grain. 
 
 Sulphur test, " " ^5;^^ grain; " " ot,"^ grain. 
 
 It need hardly be observed that these results are based upon 
 the assumption that the poison is in solution in one grain of pure 
 water, and it may be added, manipulated with care by experi- 
 enced hands. 
 
 Other Tests. — For the detection of hydrocyanic acid, Las- 
 saigne advised to precipitate it by a solution of Sulphate of 
 CoppeY, as cyanide of copper; but in every respect, this test 
 is inferior to those already mentioned. 
 
 Nitrate of Suboxide of Mercury, produces in solutions of free 
 hydrocyanic acid, and of alkaline cyanides, a dark grey or 
 nearly black precipitate of finely divided metallic mercury. 
 This reaction serves to distinguish hydrocyanic acid, and its 
 simple salts, from hydrochloric acid and its compounds, which 
 yield with the reagent a ivhite precipitate of subchloride of 
 mercury, or calomel. The application of this test, for this 
 purpose, would of course be unnecessary if the iron or sulphur 
 test has been applied. 
 
SEPARATION FROM ORGANIC MIXTURES. 187 
 
 Sepaeation from Organic Mixtures. 
 
 As hydrocyanic acid is liable to be rapidly dissipated in the 
 form of vapor, and even to undergo spontaneous decomposition, 
 the examination of a mixture in which its presence is suspected, 
 should not be delayed. The same method of research will apply 
 equally to suspected articles of food or medicine, the matters 
 vomited, and the contents of the stomach. Before resorting to 
 the application of any chemical test, the suspected mixture 
 should be carefully examined in regard to its odor; but it must 
 be borne in mind, that mixtures of this kind may contain a 
 very notable quantity of the poison, without emitting its pecu- 
 liar odor. 
 
 Examination for the Vapor. — For this purpose, the suspected 
 mixture is placed in a glass jar or any similar vessel, and the 
 mouth of the vessel then covered by an inverted watch-glass in 
 which has been previously placed a drop of nitrate of silver 
 solution. Sooner or later, even if only a minute trace of the 
 vapor is being evolved from the mixture, the silver solution 
 will acquire a white incrustation of cyanide of silver. Any 
 deposit thus produced is then examined under the microscope: 
 at the same time, the mouth of the bottle should be closed by a 
 cork, or by another watch-glass containing a drop of the silver 
 reagent. Should the microscope reveal the presence of crystals, 
 of the forms already described, these will fully establish the 
 presence of the poison, since there is no other substance that 
 will yield similar results. Should, however, the deposit be 
 amorphous, it may still, in part at least, be due to the cyanide; 
 but it might be due to the presence of chlorine, or possibly to 
 the vapor of bromine or of iodine. Under these circumstances, 
 the true nature of the deposit, if cyanide of silver, may be 
 established either by the iron or sulphur test in the manner 
 already indicated. One or both these latter tests should also 
 be applied directly to the suspected mixture, even in case the 
 silver reaction is satisfactory. 
 
 Should the silver solution, after an exposure of several min- 
 utes, fail to indicate the presence of the poison, the suspected 
 
188 HYDROCYANIC ACID. 
 
 mixture should be occasionally agitated, by shaking the bottle, 
 and the application of the reagent be continued for half an hour 
 or longer. If there is still no evidence of the presence of the 
 poison, it is not likely that it would be detected by this method, 
 even if applied for several hours; yet it must not be concluded 
 that the poison is entirely absent, even in its free state, since 
 it may be strongly retained by organic substances. In case the 
 silver reagent should fail to receive a deposit, it would of course 
 be useless to apply either of the other tests for the vapor. 
 
 Method hy simple Distillation. — After testing the suspected 
 liquid in regard to its reaction and setting apart a small portion, 
 for future examination if necessary, the remaining portion is 
 placed in a retort having its neck slightly inclined upwards and 
 connected, by means of a bent tube and corks, with a Liebig's 
 condenser, the lower end of which opens into an ordinary 
 receiver. In the absence of Liebig's condenser, the retort may 
 be connected directly with a well-cooled receiver. The liquid 
 is then distilled at a moderate heat, by means of a water-bath, 
 until about one-eighth of the fluid has passed over into the 
 receiver. On account of its volatile nature, any free hydro- 
 cyanic acid originally present in the liquid, will now be found 
 in the distillate, which may be examined in the usual manner. 
 
 If prussic acid is thus obtained and the original liquid was 
 destitute of a strongly acid reaction, then there is little doubt 
 but the poison was present in its free state, yet it may have 
 existed as an alkaline cyanide; but it could not have been in 
 the form either of a ferro- or sulpho-cyanide. To determine 
 whether it existed in its uncombined state or as an alkaline 
 cyanide, a portion of the reserved fluid is treated with a mix- 
 ture of proto- and per-sulphate of iron : if this yields no change, 
 the hydrocyanic acid is free; but if it yields Prussian-blue, 
 either at once or after the addition of hydrochloric acid, then 
 the poison exists in the form of a cyanide. If the liquid under 
 examination has an alkaline reaction, the poison, if present, 
 will of course be in the form of a cyanide, even though origin- 
 ally added in its free state. 
 
 Should the mixture in the retort evolve either hydrochloric 
 acid or sulphuretted hydrogen, this will collect with the distillate, 
 
SEPARATION FROM ORGANIC MIXTURES. 189 
 
 and interfere with the reaction of the silver test; neither of 
 these substances, however, would prevent the normal reaction 
 of either the iron or sulphur test. Hydrochloric and hydrocy- 
 anic acids may be separated, by redistilling a portion of the 
 distillate with powdered borax or carbonate of lime, which will 
 retain the chlorine compound, but not hydrocyanic acid. 
 
 Distillation with an acid. — If the above method fail to 
 reveal the presence of the poison, the contents of the retort, 
 after the addition of water if they have become thick, are 
 acidulated with sulphuric acid, and distilled as before. Any 
 simple cyanide present, would now evolve the whole of its 
 cyanogen in the form of hydrocyanic acid. Should it at first 
 be suspected that the poison existed as an alkaline cyanide, 
 this method of distillation may at once be adopted. It must 
 be remembered, however, that by this process a ferrocyanide, 
 such as ferrocyanide of potassium, or yellow prussiate of potash, 
 would also evolve prussic acid; and the same may also be true, 
 if the distillation is continued for some time, in regard to the 
 sulphocyanide of potassium, which exists in small proportion in 
 human saliva. 
 
 The source of the poison obtained in the distillate when an 
 acid has been employed, may be determined by treating a por- 
 tion of the reserved liquid, after filtration if necessary, with a 
 few drops of hydrochloric acid, and stirring the mixture for 
 some minutes, and then adding a solution of sesquichloride of 
 iron. If the liquid thus treated contained a simple cyanide, the 
 iron reagent wiU produce no visible change, since the cyanide 
 would have been converted by the hydrochloric acid added, 
 into a chloride, and the whole of the prussic acid evolved; 
 but if it contained a ferrocyanide or a sulphocyanide, this will 
 remain, and yield either a deposit of Prussian-blue or a deep 
 red solution, as the case may be. As commercial cyanide of 
 potassium is liable to be contaminated with ferrocyanide of 
 potassium, traces of the latter might be present in poisoning by 
 the former. 
 
 If there is reason to suspect that free hydrocyanic acid or 
 cyanide of ^potassium, is present with ferrocyanide of potassium, 
 they may be separated, according to Otto, in the following 
 
190 HYDROCYANIC ACID. 
 
 manner. The mixture is treated with a solution of sesquichlo- 
 ride of iron as long as a precipitate is produced, by which the 
 ferrocyanide compound will be converted into Prussian-blue; 
 carbonate of soda is then added, until the mixture exhibits an 
 alkaline reaction, then tartaric acid, until it shows a feebly acid 
 reaction; it is then distilled in the ordinary manner. By this 
 method, ferrocyanide of potassium yields a distillate entirely free 
 from hydrocyanic acid, since it is retained as Prussian-blue, 
 which is unaffected by the distillation; but when hydrocyanic 
 acid or an alkaline cyanide is present, the distillate will contain 
 the poison in its free state. 
 
 This process is admirably adapted for the separation of free 
 hydrocyanic acid from a ferrocyanide; but when the poison is 
 present in the form of an alkaline cyanide, much or even 
 the whole of it, if only in small quantity, may be retained as 
 Prussian-blue. It is true, that sesquichloride of iron produces 
 with cyanide of potassium, at first only free hydrocyanic acid, 
 sesquioxide of iron, and chloride of potassium; but this mixture 
 will after a little time form more or less Prussian-blue. This 
 conversion will, of course, take place at once, if the iron reagent 
 contains a proto-salt of the metal. 
 
 For the separation of free hydrocyanic- acid, cyanide of 
 potassium, and ferrocyanide of potassium, it has also been pro- 
 posed to distill the mixture without the addition of an acid, 
 when the free prussic acid would pass over with the distillate; 
 the residue in the retort is then filtered, the filtrate concentrated 
 to a small volume and treated with strong hot alcohol, which 
 will dissolve the cyanide, whilst the ferrocyanide would be pre- 
 cipitated in yelloM'ish-white scales, it being insoluble in this 
 liquid. 
 
 From the Blood and Tissues. — The methods already described 
 are equally applicable for the examination of any of the fluids 
 or soft solids of the body, in poisoning by prussic acid. Experi- 
 ments upon animals have shown that the poison, when intro- 
 duced into the stomach, may be difi'used throughout the blood, 
 within a few seconds. In the case already cited from Casper, 
 in which a mixture of prussic acid and some es'sential oils 
 proved fatal to a woman, the distillate obtained from about an 
 
FAILURE TO DETECT. 191 
 
 ounce of blood from the body, gave with the iron and sulphur 
 tests, very distinct evidence of the presence of the poison : the 
 silver test was not applied. The blood was treated with a 
 small quantity of spirits of wine and phosphoric acid, and dis- 
 tilled until about two drachms of fluid, smelling slightly of bitter 
 almonds, had passed over. In this case, death apparently must 
 have taken place with great rapidity, since the deceased was 
 found lying on the floor, with half a cucumber in one hand and 
 a water jug in the other. The same writer relates another 
 instance, in which an apothecary took, with suicidal intent, an 
 tinknown quantity of hydrocyanic acid, and the poison was also 
 recovered from the blood, by being distilled, in this case, with 
 a few drops of sulphuric acid. It was also found in the con- 
 tents of the stomach ; but not in the urine contained in the 
 bladder. 
 
 Failure to detect the poison. — On account of its rapidly 
 fatal effects, there is no ordinary poison more likely than hydro- 
 cyanic acid to remain in the body at the time of death ; yet on 
 account of its ready decomposition and great volatility, there is 
 perhaps none that may more rapidly disappear from the dead 
 body. The time in which a given quantity of the poison may 
 thus entirely disappear from the body, or any organic mixture, 
 will of course depend upon a variety of circumstances. In a 
 case of suicidal poisoning by hydrocyanic acid mentioned by 
 Prof. Casper, twenty-six hours after death, no trace of the poi- 
 son was found in the stomach, but there was present a consid- 
 erable quantity of formic acid, as a result of the decomposition 
 of the prussic acid. 
 
 On the other hand, cases are recorded in which the poison 
 was recovered after comparatively long periods. Thus Dr. 
 Christison quotes a case in which it was detected in a body 
 seven days after death, although the corpse had never been 
 buried, and had been for some time lying in a drain. And in 
 an instance cited by Dr. Taylor, in which a dose equivalent to 
 something -over three grains of anhydrous prussic acid proved 
 fatal in about fifty minutes, it was detected both before and 
 after distillation, in the contents of the stomach, seventeen days 
 after death. 
 
192 PHOSPHORUS. 
 
 Quantitative Analysis. — The quantity of hydrocyanic acid 
 present in a pure solution of the poison, may be readily determ- 
 ined by precipitating it as cyanide of silver. For this purpose, 
 the solution is treated with a solution of nitrate of silver as long 
 as a precipitate is produced; the mixture is then slightly acid- 
 ulated with a few drops of nitric acid, and the precipitate col- 
 lected on a filter of known weight, thoroughly washed, dried at 
 212°, and weighed. Every one hundred parts by weight of 
 cyanide of silver thus obtained, correspond to 20' 15 parts of 
 anhydrous hydrocyanic acid. 
 
 Section III. — Phosphorus. 
 
 History. — This remarkable elementary substance was first 
 discovered by Brandt, in 1669, and received its name from its 
 ready inflammability and from being luminous in the dark. 
 Phosphorus is found in the three kingdoms of nature, but most 
 abundantly as a constituent of bones, in which it exists as 
 phosphoric acid, and this in combination with lime. In its un- 
 combined state, it is a most powerful poison ; and numerous 
 instances of poisoning by it have occurred, especially since the 
 introduction of friction-matches, and of phosphorus-pastes for 
 the purpose of destroying rats. 
 
 Symptoms. — The more usual effects produced by phos- 
 phorus, when taken in poisonous quantity, are a feeling of 
 lassitude ; gaseous eructations, which have a garlic-like odor, 
 and are sometimes luminous in the dark ; burning pain in 
 the stomach and bowels ; nausea ; violent vomiting ; sometimes 
 purging ; great thirst ; cold perspirations ; great anxiety ; and 
 a feeble, irregular pulse. The matters first vomited have gen- 
 erally an alliaceous odor, and evolve white fumes, which shine 
 in the dark ; similar appearances have also been observed 
 in the faeces, which have even contained solid particles of 
 the poison. The abdolhen becomes tender to the touch ; the 
 extremities cold ; the pulse almost imperceptible ; the pupils 
 dilated and insensible ; and frequently death is preceded by 
 ccjfivulsions. 
 
PHYSIOLOGICAL EFFECTS. 193 
 
 In a case of poisoning by this substance related by Dr. 
 Lewinsky, in which a girl, aged twenty-two years, swallowed a 
 portion of phosphorus scraped from a small packet of lucifer- 
 matches, the following symptoms were observed. Soon after 
 taking the poison, the patient experienced a sharp burning pain 
 in the abdomen, followed by vomiting of matters which were 
 observed to be lumujous while being ejected from the stomach. 
 Some hours afterwards, she was suffering from vomiting and 
 purging; but no odor of phosphorus was perceptible in the 
 excretions. The abdomen was swollen and sensitive on press- 
 ure ; the tongue white, and moist ; the pulse normal, and the 
 intellect clear. Vomiting, alternating with hiccough, continued 
 unceasingly until the third day ; but the purging ceased on the 
 second day. On the third day, there were signs of jaundice ; 
 the urine was scanty and of a dark color ; and the pupils were 
 widely dilated, and nearly insensible to light. On the fourth 
 day, the jaundiced appearance of the face was much increased, 
 and there was collapse, and great restlessness, with extreme 
 thirst, and a weak, quick pulse ; but the vomiting had abated, 
 a small quantity of blood only being thrown up ; convulsions, 
 and impaired consciousness then supervened, and death occurred 
 on the sixth day after the taking of the poison. (Brit, and For. 
 Med.-Chir. Rev., Oct., 1859.) 
 
 In contrast with the above case, may be cited the following, 
 related by Prof. Casper (Forensic Medicine, vol. ii, p. 100). A 
 young lady, aged twenty years, took at six o'clock in the even- 
 ing, at least three grains of phosphorus, in the form of the 
 officinal electuary. Those around her remarked nothing pe- 
 culiar ; and during the evening she wrote a letter. Later in 
 the evening she seemed to her family to exhale "sulphur" 
 (evidently confounding the vapor of sulphur with that of phos- 
 phorus-matches), and complained that the light blinded her, but 
 made no complaint whatever of pain. During the night, which 
 she passed sleeplessly, she vomited once, and died quite peace- 
 fully at six o'clock in the morning, just twelve hours after 
 taking the poison. 
 
 Period when Fatal. — In fatal poisoning by phosphorus, death 
 usually takes place in from one to three days. The most 
 
 13 
 
194 PHOSPHORUS. 
 
 rapidly fatal case yet recorded, is perhaps that related by Prof. 
 Casper, just mentioned, in which death occurred in twelve 
 hours. In a case quoted by Dr. Christison, the taking of a 
 portion of lucifer-match composition, was followed by vomiting, 
 pain in the abdomen, anxiety, restlessness, excessive thirst, and 
 death in fifteen hours (Op. cit., p. 151). In an instance reported 
 by Dr. Flachsland, a young man, aged twenty-four years, took 
 an unknown quantity of the poison, spread on bread with butter. 
 He soon experienced violent pain in the stomach and bowels, 
 and intense vomiting, which continued the following day : after 
 the use of clysters, he passed small fragments of phosphorus, 
 which were luminous in the dark and burned spots in the bed- 
 linen. Death ensued in forty hours after the poison had been 
 taken. (Medizinisch-Chirurgische Zeitung, 1826, iv, p. 183.) 
 Orfila, in quoting this case (Toxicologic, 1852, i, 84), errone- 
 ously states that death took place in "four" hours. 
 
 Among the more protracted cases, may be mentioned the 
 following. M. Diffenbach, an apothecary of Biel, as a matter 
 of experiment, took one grain of phosphorus, on the 2d of July, 
 1823. On the 21st of the same month he took two grains, and 
 on the following day increased the dose to three grains. During 
 the evening of the last day, he experienced uneasiness and a 
 sense of pressure in the abdomen. These symptoms were suc- 
 ceeded by violent and incessant vomiting, convulsions, delirium, 
 and partial paralysis, and death ensued on the 29th of the 
 month, or the seventh day after the last dose of poison had been 
 taken. (Revue Mddicale, 1829, iii, 429.)* In a case quoted by 
 Dr. Beck, in which a young man took .one grain and a half of 
 phosphorus, death did not occur until the twelfth day, after the 
 taking of the poison. (Med. Jur., vol. ii, p. 511.) This seems 
 to be the most protracted case yet recorded. 
 
 Fatal Quantity. — The efi'ects of a given quantity of phos- 
 phorus will depend much upon the state in which it is taken. 
 A child, two years and a half old, died after swallowing the 
 phosphorus contained on eight friction-matches ; and a child, 
 
 «For the examination of the original publication of this case, as well as of 
 that reported by Dr. Flachsland, I am indebted to the kindness of Dr. Schiiller, 
 ■ of Wurzburg, Bavaria. 
 
ANTIDOTES. 195 
 
 two montlis old, is said to have died from the effects of two such 
 matches. (Wharton and Stille, Med. Jur., p. 505.) The quantity 
 of the poison taken in ' the last-mentioned instance, could not 
 have much exceeded the fiftieth part of a grain. In a case 
 quoted by Dr. Taylor, one-eighth of a grain destroyed the life 
 of a lunatic. In another instance, the composition from thirty 
 or forty lucifer-matches, administered with milk, proved fatal to 
 a woman, in less than forty-eight hours. (London Chem. News, 
 AprU, 1860, p. 207.) Again, Dr. Christison quotes the case of 
 a patient, afFected with lead-palsy, who died in about two days 
 from the effects of considerably less than a grain of the poison, 
 taken in the form of an emulsion. 
 
 On the other hand, a case is related in which a child swal- 
 lowed nearly a teaspoonful of phosphorus-paste, prepared for 
 killing rats, and, under the free administration of magnesid, 
 entirely recovered. (U. S. Dispen., 1865, p. 644.) The quan- 
 tity of phosphorus taken in this case, probably exceeded one 
 grain. In a case quoted by Dr. Taylor, a young woman 
 swallowed the phosphorus obtained from about three hundred 
 matches — equal to rather less than five grains of the poison — 
 and recovered without any very severe symptoms. (On Pois- 
 ons, p. 345.) These are the most remarkable instances of 
 recovery, after the taking of this poison, yet recorded; in fact, 
 very few cases of recovery have as yet been reported. 
 
 Treatment. — No chemical antidote is known to the action 
 of this poison. If there is not already free vomiting, it should 
 be induced by the exhibition of Sjn emetic. Calcined mag- 
 nesia, suspended in large draughts of any demulcent liquid, 
 may then be freely administered : this may serve to neutralise 
 any oxide of phosphorus remaining in the stomach. Instances 
 are related in which this treatment was employed with great 
 success. It has been proposed to administer the magnesia in 
 suspension in chlorine water; but more recent experiments on 
 animals, have indicated that this mixture has no special ad- 
 vantage. Since phosphorus is somewhat soluble in fatty sub- 
 stances, the administration of these should be avoided. If the 
 poison has passed into the intestines, purgatives may be used 
 with advantage. 
 
196 PHOSPHORUS. 
 
 Post-mortem Appearances. — The contents of the stomach 
 have in some instances evolved white fumes, having an allia- 
 ceous odor, and being luminous in the dark. The lining mem- 
 brane of the stomach is generally much inflamed, and has even 
 presented a gangrenous appearance ; these appearances may- 
 extend throughout the intestines, which are often much con- 
 tracted. The liver, spleen, and kidneys are often highly red- 
 dened, the lungs gorged with blood, the heart empty, and the 
 brain congested. The blood throughout the body is usually 
 dark colored and remarkably fluid. 
 
 In 'the case fatal in twelve hours, related by Prof. Casper, 
 forty-eight hours after death, luminous vapors were observed 
 to issue from the vagina, and a greyish-white vapor smelling 
 strongly of phosphorus continuously streamed from the anus ! 
 A very distinct odor of phosphorus also came from the mouth, 
 but without any visible vapor. The stomach itself diffused no 
 odor of phosphorus ; and no part of its mucous membrane was 
 either softened or corroded. It contained about six to eight 
 ounces of a bright, bloody-like fluid, mingled with coagulated 
 milk ; no particles of phosphorus could be detected in the 
 stomach, even with a magnifying glass. The intestines were 
 pale, and presented nothing abnormal. The blood was dirty- 
 red, of a syrupy consistency, and the blood-corpuscules were 
 transparent and deprived of their coloring-matter. The liver, 
 spleen, and kidneys were congested. The bladder was of a 
 livid color, and contained about a tablespoonful of milky urine. 
 The lungs contained but little blood, and the heart was almost 
 completely empty ; but the large blood-vessels contained much 
 blood. The meninges were moderately congested, and the brain 
 contained more blood than usual. 
 
 In Dr. Lewinsky's case, in which death occurred on the 
 sixth day, the stomach was filled with gas and a blackish- 
 brown fluid; its mucous coat was raised from beneath, and 
 covered with a thick mucus, streaked with dark-brown lines. 
 The intestines contained a blackish-brown, thin frothy liquid. 
 The bladder was contracted and empty. The cavity of the 
 throat contained a bloody, frothy mucus, which extended into 
 the bronchial tubes. The lungs were covered with a flaky 
 
CHEMICAL PROPERTIES. 197 
 
 exudation. The heart was contracted, and its cavities con- 
 tained fluid blood with a little coagulated fibrin. The structure 
 of the brain was free from blood, but the ventricles contained 
 a drachm of serum. A chemical examination of the stomach 
 and its contents, by Dr. Schauenstein, showed no indication of 
 the presence of phosphorus. 
 
 In the case reported by Dr. Flachsland, which proved fatal 
 in forty hours, watery blood flowed in large quantity from the 
 nostrils ; and also from the first incisions made into the skin 
 and muscles of the abdomen. The stomach and bowels exter- 
 nally were inflamed ; the mucous membrane of the stomach pre- 
 sented a gangrenous inflammation, which extended into the 
 duodenum ; the large intestines were cpntracted to the size of 
 the little finger. The mesenteric glands were hardened ; and 
 the spleen and kidneys inflamed. 
 
 Chemical Properties. 
 
 GrENEEAL Chemical Natuee. — Phosphorus, at ordinary tem- 
 peratures, is a soft, colorless, transparent solid, having a waxy 
 appearance, and a specific gravity, according to Schrotter, of 
 1-83. It fuses at a temperature of about 110°, and boils at 
 550° F. When exposed to the air, it slowly absorbs oxygen, 
 and emits white fumes of phosphorous acid; at the same time 
 it exhales a peculiar garlic-like odor,, and the fumes are lumin- 
 ous in the dark. Berzelius believed that this luminosity was 
 due to the volatilisation of free phosphorus, but Schrotter has 
 shown that it is due to the combination of the phosphorus with 
 oxygen. (Chem. Graz., vol. xi, p. 312.) This oxidation, and 
 consequently the luminosity, is prevented by the presence of the 
 vapor of ether, alcohol, turpentine, and of certain other liquids, 
 even when these are present only in minute quantity. 
 
 Heated in the open air, phosphorus takes fire at a temperature 
 of about 140°, and burns with a brilliant white light, evolving 
 dense white fumes of phosphoric acid. The presence of certain 
 oxidising agents causes it to inflame at much lower temperatures. 
 
 Solubility. — Phosphorus is insoluble in water, but it dissolves 
 to a limited extent in fixed and volatile oils, especially by the 
 
, 198 PHOSPHORUS. 
 
 aid of heat. It also dissolves to a limited extent in ether, and 
 somewhat more freely in hot naphtha, from which, however, it 
 partially separates on cooling in rhombic dodecahedral crystals. 
 It is freely soluble in chloride of sulphur, and in bisulphuret of 
 carbon ; five parts of the latter liquid dissolve one of phos- 
 phorus (Graham). It is insoluble in hydrochloric acid, but 
 warm nitric acid readily oxidises and dissolves it, in the form 
 of phosphoric acid. 
 
 When phosphorus is immersed in water and exposed to the 
 action of light, it slowly becomes covered with a white opake 
 coating, which, according to H. Rose, is nothing more than 
 pure phosphorus, the change being simply due to a change in its 
 state of aggregation. At the same time, however, a little of the 
 phosphorus undergoes oxidation, and is dissolved by the liquid. 
 
 Varieties. — Of the several allotropic forms of phosphorus, 
 the Red or amorphous variety is the only one that need be 
 mentioned. This form is obtained by heating ordinary phos- 
 phorus in an atmosphere of carbonic acid or of any gas that 
 does not act upon it chemically, when after a time it will be- 
 come converted into a dark-red amorphous mass, from which 
 any unchanged phosphorus may be dissolved by treating the 
 mixture with bisulphuret of carbon. 
 
 This variety of phosphorus differs, not only in respect to its 
 physical properties, but also in regard to its physiological effects 
 and chemical properties, .from ordinary phosphorus, although 
 its ultimate composition is precisely the same. Thus, it is des- 
 titute of odor, and does not become luminous in the dark until 
 heated to about 400°. Its fusing point is about 480° ; at a 
 temperature of about 500° it is reconverted into ordinary phos- 
 phorus. It is insoluble in bisulphuret of carbon, terchloride of 
 sulphur, ether, alcohol, and in naphtha ; but it is sparingly solu- 
 ble in oil of turpentine. Moreover, from experiments on ani- 
 mals, it appears to be entirely destitute of poisonous properties. 
 
 Special Chemical Properties. — The physical appearance 
 of phosphorus, together with its odor, the production of white 
 fumes when exposed to the air, its ready inflammability, and 
 its phosphorescence in the dark, readily serve to distinguish it 
 in its solid state, even in very minute quantity. 
 
SPECIAL CHEMICAL PROPERTIES. 199 
 
 When a mixture containing free phosphorus is gently heated, 
 best by means of a water-bath, in a test-tube, in the neck of 
 which is suspended a slip of filtering-paper moistened with a 
 solution of nitrate of silver, the vaporised phosphorus on coming 
 in contact with the silver compound decomposes it, with the 
 production of phosphoric acid and the elimination of metallic 
 silver, which imparts to the paper a brown or black coloration. 
 A very minute trace of the poison will thus manifest itself. 
 
 Since, however, there are several other vapors that will 
 blacken a solution of nitrate of silver, this change taken alone 
 would not prove the presence of phosphorus. That the result 
 is really due to the presence of phosphorus, may be determined 
 by digesting the blackened paper with a small quantity of hot 
 water, precipitating any undecomposed nitrate of silver present 
 by hydrochloric acid, filtering, and examining the concentrated 
 filtrate for phosphoric acid, in the manner hereafter indicated. 
 
 When phosphorus in its free state is mixed with diluted sul- 
 phuric acid and zinc in a test-tube, or any convenient vessel, a 
 portion of the hydrogen gas evolved, by the action of the acid 
 and zinc, unites with the phosphorus with the production of 
 phosphuretted hydrogen gas, which is luminous in the dark, 
 and sometimes spontaneously inflammable. A very small quan- 
 tity of phosphorus will in this manner evolve a phosphorescent 
 gas for half an hour or longer ; and when the experiment is 
 performed in a small, narrow test-tube and in a perfectly dark- 
 ened room, or better at night, the least visible quantity of the 
 poison will yield very satisfactory flashes of light, which con- 
 tinue to be produced for some time. 
 
 If the phosphuretted hydrogen thus evolved, together with 
 the free hydrogen, be conducted through a drawn-out tube, and 
 ignited, they burn with a greenish flame surrounded by a deli- 
 cate blue mantle. A paper moistened with nitrate of silver 
 solution and exposed to the unignited gas, is immediately black- 
 ened. If the gas be conducted into water, it gives rise to white 
 fumes as it escapes from the liquid. With a solution of nitrate 
 of silver, it gives rise to phosphoric acid, which remains in 
 solution, and a black precipitate, consisting of a mixture of 
 metallic silver and phosphide of silver. When conducted into 
 
200 
 
 PHOSPHORUS. 
 
 a solution of corrosive sublimate, it produces a yellow or 
 yellowish-white precipitate, which, according to H. Rose, con- 
 sists of phosphide and chloride of mercury. 
 
 1. Mitscherlich'S Method. 
 
 The most delicate method yet proposed for the detection of 
 uncombined phosphorus, is that first pointed out by E. Mitscher- 
 lich. It consists in distilling the substance containing the phos- 
 phorus with diluted sulphuric acid, and conducting the evolved 
 vapors through a glass tube surrounded by a condenser. The 
 vapor of phosphorus is thus condensed, and gives rise to a con- 
 tinuous luminosity, when observed in the dark. 
 
 Fig. 2. 
 
 Mitscherlich'S Apparatus for the detection of Phosphorus. 
 
 For the application of this method, the phosphorus mixture, 
 after the addition of water if necessary, is acidulated with sul- 
 phuric acid and placed in a glass flask. A, Fig. 2. The flask 
 
MITSCHERLICH'S TEST. 201 
 
 is connected by means of an exit-tube, a, with a delivery tube, 
 &, which is bent at a right angle, and after passing through a 
 glass cylinder, B, filled with cold water, terminates in a drawn- 
 out point within a small bottle, which serves as a receiver. 
 The condenser may be readily constructed by taking a glass 
 tube, about twenty inches in length and one inch and a half in 
 diameter, and closing the ends with good corks, the upper of 
 which has three perforations, while the lower has one for the 
 passage of the delivery tube : the condenser is supplied with 
 cold water from the reservoir C, the liquid being conducted by 
 a funnel-tube, c, to the bottom of the condenser ; the warmed 
 water is carried off from the surface of the liquid by a syphon, 
 d. Having thus adjusted the apparatus, a dark screen is placed 
 between the flask and the condenser. 
 
 On now gently boiling the contents of the flask, while a 
 stream of cold water flows through the condenser, a very dis- 
 tinct and continuous luminosity, usually some inches in length, 
 will be observed in the dark to play up and down the cooled 
 portion of the delivery tube. The phosphorus thus distilled, 
 collects with the condensed aqueous vapor in the receiver, and 
 imparts to the liquid a strong alliaceous odor. When the quan- 
 tity of phosphorus is not too minute, a portion of it collects in 
 the receiver in the form of small globules ; a portion of it, how- 
 ever, always undergoes oxidation and remains in solution in the 
 distillate, in the form of phosphorous acid, and also, sometimes, 
 as phosphoric acid. The true nature of any globules thus ob- 
 tained may be determined even by their physical properties. 
 
 The presence of phosphorous acid in the distillate may be 
 shown, by treating the filtered liquid with a solution of nitrate 
 of silver or of chloride of mercury; but as both these reagents 
 produce precipitates with various kinds of organic matter, which 
 if present in the original mixture might distill over, it is always 
 best, when examining a suspected mixture, to convert the phos- 
 phorous acid into phosphoric acid before testing. For this pur- 
 pose, the distillate is treated with a few drops of nitric acid, 
 concentrated to a small volume, filtered if necessary, aiid then 
 examined by molybdate of ammonia or any of the other tests 
 pointed out hereafter for the detection of phosphoric acid. 
 
202 PHOSPHORUS. 
 
 When in the exammation of a suspected mixture, a lumin- 
 osity has been observed during the distillation, and globules of 
 phosphorus have collected in the receiver, it is wholly unneces- 
 sary to examine the condensed liquid. On the other hand, if 
 no luminosity or globules of phosphorus have been obtained, 
 great care should be exercised in regard to any deductions from 
 the detection of a mere trace of phosphoric acid in the distil- 
 late, since it may have been carried over mechanically from the 
 mixture submitted to distillation. It may be remarked, that it 
 is only when the original mixture contains unoxidised phos- 
 phorus that a luminosity and globules of phosphorus will be 
 obtained, as neither phosphorous acid nor phosphoric acid, yield 
 either of these results ; nor will either of these oxides appear 
 in the distillate, even when present in the original mixture in 
 large quantity, unless they be carried over mechanically with 
 the vapor of water. 
 
 Delicacy of this Method. — Mitscherlich distilled five ounces 
 of a mixture containing the fortieth part of a grain of pure 
 phosphorus — that is, one part of phosphorus in little less than 
 one hundred thousand parts of the mixture — and the luminosity 
 continued until three ounces of liquid distilled over, which 
 required about half an hour. In another experiment, he dis- 
 tilled five omices of a mixture containing one-third of a grain 
 of phosphorus, and obtained such a number of globules of phos- 
 phorus in the distillate, that one-tenth part of them would have 
 sufiiced to establish their true nature. 
 
 In one of our own experiments, the fiftieth part of a grain 
 of phosphorus was distilled with two thousand fluid-grains of 
 water, acidulated with sulphuric acid. As soon as the mixture 
 was brought to the boiling temperature, a phosphorescent light 
 some inches in length appeared in the tube, within the con- 
 denser, and continued without intermission for thirty-four min- 
 utes, at which time the distillation was stopped, and eighteen 
 hundred and twenty grains of fluid had distilled over. The 
 distillate had a strong alliaceous odor, but it contained no 
 globules of phosphorus ; it however readily furnished evidence 
 of the presence of oxides of phosphorus. The amount of 
 phosphorus that passed through the tube per second, in this 
 
HYDROGEN TEST. 203 
 
 experiment," must have been something less than the 100,000th 
 part of a grain ; yet this gave a luminosity many times greater 
 than would have sufficed to recognise its presence with absolute 
 certainty. 
 
 Interferences. — It has already been remarked that the pres- 
 ence of certain vapors may entirely prevent the luminosity of 
 phosphorus. Thus if the mixture subjected to distillation con- 
 tained alcohol, ether, or oil of turpentine, no luminosity would 
 be observed as long as these distilled over. Alcohol and ether, 
 being very volatile, would soon be separated, and the light 
 would then appear ; but this would not be the case in regard to 
 the presence of oil of turpentine : this liquid, however, is not 
 at all likely to be present m a medico-legal examination for 
 phosphorus. M. Lipowitz has shown that the phosphorescence 
 is also interfered with by the presence of ammonia ; but this 
 substance would be neutralised by the sulphui-ic acid added. 
 
 According to Dr. F. Hoffman, who has made a series of over 
 one hundred and fifty experiments after Mitscherlich's method, 
 the reaction is not interfered with by the presence of either 
 tartar emetic, magnesia, oxide of iron, musk, castor, opium, 
 albumen, any of the metallic salts, volatile organic acids, nor 
 by free acids ; but it is interfered with or entirely prevented by 
 iodine, calomel and corrosive sublimate in large quantity, and 
 metallic sulphurets in the presence of free sulphuric acid, and 
 particularly oil of wormseed. (London Chem. News, Jan., 1861, 
 p. 50.) The same observer remarks, that numerous experi- 
 ments, by distilling the brain of various animals, blood, albu- 
 men, casein, fibrin, legumen, and other proteine compounds, 
 with dilute sulphuric acid, failed to yield the least phosphor- 
 escence. 
 
 2. Hydrogen Method. 
 
 This method, first devised by E. Dusart and since improved 
 by Fresenius, is based upon the property possessed by free 
 phosphorus, and the lower oxides of phosphorus, of forming 
 with nascent hydrogen phosphuretted hydrogen, which burns 
 with a greenish flame. The color of the flame is not dimin- 
 ished in intensity by conducting the mixed gases over hydrate 
 
204 PHOSPHORUS. 
 
 of potash or caustic lime: these latter substances would retain 
 any sulphuretted hydrogen present, which burns with a blue 
 flame and thus interferes with the phosphorus reaction. 
 
 An ordinary gas-evolution flask is charged with pure diluted 
 sulphuric acid and zinc, and the evolved hydrogen, after being 
 conducted over pumice-stone moistened with a saturated solution 
 of caustic potash, ignited as it escapes from a drawn-out tube 
 provided with a platinum burner. If the gas burns with a 
 colorless flame, the phosphorus mixture is introduced, by means 
 of a funnel-tube, into the flask, when the evolved gas will burn 
 with a characteristic green color, which disappears if the tube 
 becomes heated. For this reason the end of the tube should be 
 surrounded with moistened cotton. If a piece of cold porcelain 
 be depressed in the flame, the latter burns with an emerald-green 
 color at the points of contact, until the porcelain becomes heated. 
 
 Oa following this method, E. Dusart obtained from about 
 the sixth of a grain of the paste of matches, a flame that not 
 only burned for an hour and a half with a visible green tint, 
 but also produced on porcelain spots of a yellowish-red color, 
 which resembled finely reduced phosphorus. (Jour, de Chim. 
 M^d., 1863, p. 663.) The evolved gas has a peculiar odor, and 
 is luminous in the dark. The peculiar odor of hydrogen when 
 obtained from iron and dilute acids, according to Dusart is due 
 to the presence of phosphuretted hydrogen. 
 
 The phosphide of silver yields by this method the same 
 results as free phosphorus. The silver compound may be ob- 
 tained by gently heating the phosphorus mixture, acidulated 
 with sulphuric acid, for some hours in a flask through which a 
 slow stream of carbonic acid gas is being passed, and coUecting 
 the evolved vapor in a solution of nitrate of silver. In this 
 operation, the vaporised phosphorus passes through the atmos- 
 phere of carbonic acid without undergoing any change; but on 
 coming in contact with the silver solution, it gives rise to solid 
 phosphide of silver and free phosphoric acid. The phosphide 
 of silver is collected and washed on a filter, which has pre- 
 viously been washed in diluted nitric acid and water; it is then 
 suspended in a little water and introduced into the hydrogen 
 apparatus. The presence of phosphoric acid in the filtrate, 
 
LIPOWITZ'S TEST. 205 
 
 separated from the silver compound, may be determined in the 
 manner heretofore indicated. 
 
 Fresenius states that he obtained by this process the clearest 
 evidence of the presence of phosphorus in a large quantity of 
 putrid blood mixed with the composition scraped from the tip 
 of a common lucifer-match ; and this even in the presence of 
 substances which prevent the luminosity of the phosphorus in 
 expe'riments by Mitscherlich's method. 
 
 3. Lipowitz^s Method. 
 
 This method is based upon the property possessed by sulphur 
 when heated with free phosphorus, of combining with it, even 
 when present in very complex mixtures and in a. highly com- 
 minuted state, and producing a compound in which the presence 
 of the poison is readily determined. The phosphorus mixture, 
 slightly acidulated with sulphuric acid, is gently boiled for about 
 half an hour in a retort with a few small pieces of sulphur, the 
 distillate being collected in an ordinary receiver. 
 
 The fragments of sulphur are then separated from the cooled 
 mixture, and washed with water. They will now emit the pecu- 
 liar odor of phosphorus, and be luminous in the dark. When 
 gently heated with strong nitric acid, they yield a solution con- 
 taining phosphoric acid, together with more or less sulphuric 
 acid. The presence of phosphoric acid in this mixture may be 
 shown by evaporating the hquid to a small volume, diluting 
 with a little water, filtering, neutralising the filtrate with am- 
 monia, and applying the magnesia test, hereafter described. 
 
 The liquid that distills over into the receiver will usually 
 contain one or more of the oxides "of phosphorus, and have 
 an alliaceous odor. When however only a minute quantity of 
 phosphorus is present in the original mixture, the whole of it 
 may be retained by the sulphur. 
 
 By this method, Lipowitz states that he detected phosphorus 
 in complex organic mixtures containing only the 140,000th part 
 of their weight of the poison. 
 
 Since in medico-legal investigations for phosphorus, it often 
 becomes necessary to recover the poison, in part at least, as 
 
206 PHOSPHORIC ACID. 
 
 phosphoric acid, before describing the methods of separating the 
 former from organic mixtures, the general nature and chemical 
 properties of the latter will be considered. 
 
 Phosphoric Acid. 
 
 General Chemical Nature. — Phosphoric acid is a com- 
 pound of one chemical equivalent of phosphorus with five 
 equivalents of oxygen (PO5) ; it is the highest oxide of phos- 
 phorus known. In its anhydrous state, it forms a snow-white 
 amorphous mass, which' has a strong affinity for water, and 
 rapidly deliquesces when exposed to the air, forming a hydrate. 
 Hydrated phosphoric acid is usually prepared by boiling phos- 
 phorus with diluted nitric acid, and evaporating the solution 
 until on cooling, it solidifies to a hard transparent mass; in 
 this state, the acid is commonly known as glacial phosphoric 
 acid, and contains these equivalents of water (3 HO ; PO5). 
 
 Phosphoric acid, at least in its common form, is capable 
 of uniting with three equivalents of a metallic base, for each 
 equivalent of the acid; it is therefore tribasic. The salts of 
 this acid, except those of the alkalies, are insoluble in water; 
 but they are freely soluble in the presence of a free acid, even 
 in most instances of acetic acid. 
 
 Special Chemical Properties. — In the following investiga- 
 tions of the reactions of reagents with solutions of phosphoric 
 acid, the latter was employed in the form of common phosphate 
 of soda. The fractions indicate the amount of anhydrous phos- 
 phoric acid in solution in one grain of water; the results, 
 unless otherwise stated, refer to the behavior of one grain of 
 the solution. 
 
 1. Nitrate of Silver. 
 
 This reagent fails to produce a precipitate in solutions of 
 free phosphoric acid; but in neutral solutions of the alkaline 
 phosphates, it occasions a light-yellow precipitate of tribasic 
 phosphate of silver (3 AgO ; PO5). The precipitate is readily 
 soluble in ammonia, and also in~ nitric, acetic, and free phos- 
 phoric acids; hydrochloric acid changes it to white chloride of 
 
MAGNESIAN TEST. 207 
 
 silver. From dilute solutions, the formation of tlie precipitate 
 is much facilitated by the aid of a gentle heat. 
 !• Too grain of phosphoric acid, in one grain of water, yields 
 a copious, yellow deposit, which remains amorphous. 
 
 2. 1,0% grain, yields a very good precipitate. 
 
 3. 10,000 grain: a very satisfactory deposit, of a very pale- 
 
 yellow color. The precipitate from ten grains of the 
 solution, has a very satisfactory yellow color. 
 4- 5 0,000 grain: after a very little time, a quite distinct cloudi- 
 ness appears. Ten grains of the solution, yield a very 
 satisfactory turbidity, but the yellow color is not apparent. 
 Nitrate of silver also throws down from neutral solutions of 
 arsenious acid a yellow precipitate, which, however, usually 
 becomes crystalline. The arsenical precipitate, like that from 
 phosphoric acid, is readily soluble in ammonia, and in free 
 acids; but when dried, and heated in a reduction-tube, it yields 
 a sublimate of octahedral crystals, of arsenious acid, in which 
 it is readily distinguished from the phosphorus compound. The 
 reagent produces yellowish-white precipitates in solutions of 
 iodides and of bromides; but these precipitates are insoluble 
 in dilute nitric acid, and only sparingly soluble in ammonia. 
 
 2. Sulphate of Magnesia. 
 
 This reagent throws down from strong solutions of the alka- 
 line phosphates, but not of free phosphoric acid, a white amor- 
 phous precipitate of phosphate of magnesia. The quantity of 
 the precipitate is much increased by boiling the mixture. One 
 grain of a 100th solution of phosphoric acid, in the form of an 
 alkaline phosphate, yields a very good precipitate, without the 
 application of heat. Ten grains of the same solution, yield 
 upon boiling the mixture, a very copious deposit. Ten grains 
 of a 1,000th solution remain clear on the addition of the re- 
 agent, but when the mixture is boiled, it yields a quite good 
 flocculent precipitate. 
 
 A mixture of sulphate of magnesia, chloride of ammonium, 
 and free ammonia, produces in solutions of free phosphoric 
 acid and of alkaline phosphates, a white crystalline precipitate 
 
208 PHOSPHORIC ACID. 
 
 of ammonio-phosphate of magnesia (2 MgO ; NH4O, PO5, 12 Aq). 
 This reaction is much more delicate and characteristic than 
 that produced by sulphate of magnesia alone. The formation 
 of the precipitate from very dilute solutions, is much facilitated 
 by stirring the mixture with a glass rod. The precipitate is 
 readily soluble in free acids, but insoluble in ammonia, even 
 more so than in pure water. 
 
 1. Y^ grain of phosphoric acid, when treated with the above 
 
 mixture, yields a very copious, gelatinous precipitate, which 
 in a little time becomes crystalline. 
 
 2. 1,000 grain: a copious precipitate, which immediately begins 
 
 to crystallise, and soon becomes entirely converted into 
 feathery and stellate crystals, Plate IV, fig. 3. 
 3- 5,0*0 grain : an immediate crystalline precipitate, which soon 
 becomes rather abundant. 
 
 4. 10,1)0 grain, yields an immediate cloudiness, and in a little 
 
 time a crystalline deposit. 
 
 5. 2 5.000 grain : in a very little time the mixture becomes tur- 
 
 bid, and crystals can be seen by the microscope ; after a 
 few minutes, there is a quite satisfactory crystalline deposit. 
 
 6. 5 0,000 grain : after a few minutes crystals appear to the mi- 
 
 croscope, and after some minutes they are quite obvious to 
 the naked eye. 
 7- 10 0% 00 grain : after about fifteen minutes, crystals are per- 
 ceptible to the naked, eye. 
 This reagent mixture also produces a similar crystalline 
 precipitate in solutions of arsenic acid. When, however, the 
 arsenical precipitate is dissolved in just sufficient acetic acid, 
 and the solution treated with nitrate of silver, it yields a reddish- 
 brown deposit ; whereas, the phosphoric precipitate, when treated 
 in the same manner, yields a white deposit. The same reddish- 
 brown precipitate is produced by nitrate of silver from normal 
 solutions of arsenic acid. 
 
 3. Molyidate of Ammonia. 
 
 To apply this test, molybdate of ammonia is mixed with 
 sufficient hydrochloric or nitric acid -to redissolve any precipitate 
 
MOLYBDIC ACID TEST. 209 
 
 that first forms ; or according to Sonnenschein, who first pointed 
 out the test, one part of molybdic acid is dissolved in eight 
 parts of ammonia solution and twenty parts of nitric acid. A 
 small quantity of this mixture is then placed in a test-tube, and 
 a few drops of the phosphoric acid solution added, when, if the 
 reagent is greatly in excess, the mixture will acquire a yellow 
 color and yield a yellow pulverulent precipitate of phospho- 
 molybdate of ammonia. From very dilute solutions of the acid, 
 the precipitate is slow to appear ; the reaction is greatly pro- 
 moted by a gentle heat. The precipitate consists of molybdic 
 acid, ammonia, water, and phosphoric acid. According to M. 
 Seligsohn (Chem. Gaz., 1856, p. 427), it contains .3-142 per 
 cent, of the latter, its formula being 60 M0O3; 2 (SNE^O; PO5) ; 
 15 HO. 
 
 In the presence of excess of the reagent, phospho-molybdate 
 of ammonia is insoluble in nitric, hydrochloric, and most other 
 acids, even on boiling ; but it is readily soluble in excess of free 
 phosphoric acid and of alkaline phosphates, the caustic alkahes 
 and their carbonates, and in the alkaline tartrates. (Chem. 
 Gaz., vol. X, 1852, pp. 216, 390.) 
 
 In examining the limit of the reaction of this test, a very 
 strong solution of molybdate of ammonia was prepared by dis- 
 solving the salt in large excess of hydrochloric acid ; one fluid- 
 grain of the phosphoric acid solution was then added to about 
 five grains of the test-fluid, placed in a small test-tube. 
 !• Too" grain of phosphoric acid produces an immediate yellow 
 solution, and a bright-yellow precipitate, which in a little 
 time becomes quite copious. The precipitate is much 
 increased in quantity by warming the mixture. 
 2. 1 , J grain : the mixture immediately assumes a yellow 
 color, and in a little time yields a copious yellow de- 
 posit. If the precipitate be dissolved in the mixture by 
 excess of ammonia, and then a mixture of sulphate of 
 magnesia and chloride of ammonium added, it yields an 
 immediate crystalline precipitate of ammonio-phosphate 
 of magnesia, not to be distinguished from that thrown 
 down from a pure solution of phosphoric acid of the same 
 strength. 
 
 14 
 
210 PHOSPHORUS. 
 
 3. 1 ?o grain: the mixture immediately assumes a yellow tint, 
 whiah increases in intensity, and in a little time a yellow 
 precipitate separates. Upon gently heating the mixture, 
 it yields a good, yellow deposit, 
 ■i- 5 ,0 u "u grain : after a little time the mixture acquires a yellow 
 tint ; by heat, the yellow color becomes very distinct, and 
 yellow flakes separate. These gather upon the surface of 
 the fluid and form an adherent, yellow pellicle. 
 5.- 1 0% grain : after several minutes, no perceptible change. 
 But if the mixture be heated, it assumes a distinctly yel- 
 low color, and after a time small yellow flakes appear upon 
 the surface of the liquid. 
 This reagent also produces a yeUow coloration and precipi- 
 tate in solutions of arsenic acid, but only, however, as first 
 pointed out by Sonnenschein, when the mixture is heated to 
 about the boihng temperature. The absence of this acid may 
 be shown by nitrate of silver, in the manner already indicated. 
 So also, on the application of heat, the reagent imparts a yellow 
 color to solutions of silicic acid; but this substance yields no 
 precipitate, nor does it even yield a yellow coloration unless the 
 mixture be heated. 
 
 Other Reactions. — Phosphoric acid is also precipitated, at 
 least from neutral solutions, by acetate of lead, soluble salts of 
 baryta, strontia, lime, and of several other metals. The lead 
 precipitate is almost wholly insoluble in acetic acid, but most 
 of the other precipitates are readily soluble in this acid. These 
 reactions, however, are common to solutions of several other 
 acids, and in most instances are much inferior in delicacy to 
 the tests already mentioned. 
 
 Separation of Phosphoeus from Organic Mixtures. 
 
 The odor emitted by phosphorus is so peculiar that it will 
 often serve to detect the poison with considerable certainty, 
 even when present in very complex mixtures. It must be 
 remembered, however, that the presence of other odors may 
 entirely conceal that of this substance, especially if it is present 
 
SEPARATION FROM ORGANIC MIXTURES. 211 
 
 only in minute quantity. "We have even found this to be the 
 case when comparatively large quantities of the poison were 
 purposely added to animal mixtures which were undergoing de- 
 composition. According to Dr. F. Hoffman (Chem. News., iii, 
 50), coffee, mustard, smoked meat, highly seasoned food and 
 beverages, and medicines containing odorous gum-resins, vola- 
 tile oils, musk, castor, camphor, and chlorine, have the property 
 of concealing the odor of the poison, at least if present only in 
 minute quantity. 
 
 Organic mixtures containing free phosphorus, when exposed 
 to the air, usually evolve vapors which are luminous in the dark, 
 especially if the mixture be gently heated, and stirred. If on 
 thus examining the mixture, any solid particles of the poison 
 are found, they may be washed in water, then in alcohol, and 
 preserved for future examination if necessary. If the mixture 
 under examination is ammoniacal from putrefaction, before being 
 examined in regard to its luminosity, it should be acidulated 
 with sulphuric acid. Should these means fail to prove the 
 presence of the poison, the suspected mixture is examined by 
 one or other of the following methods. 
 
 Mitscherlich's MetJiod. — A comparatively large portion of the 
 mixture, acidulated with sulphuric acid, may be examined after 
 this method. As this is the most satisfactory process yet pro- 
 posed for the detection of free phosphorus, it should never be 
 omitted, unless the poison has already been discovered in its 
 solid state. If during the distillation, the contents of the flask 
 become thick, they should be diluted with water, and the 
 process continued as long as any. luminosity appears in the 
 condensing-tube. If the distillate thus obtained, contains any 
 globules of phosphorus, they are carefully separated from the 
 liquid, then washed, dried between folds of bibulous paper, and 
 weighed. The liquid may then, aifter the addition of a few 
 drops of nitric acid, be concentrated to a small volume, and a 
 portion of it examined by molybdate of ammonia, for phos- 
 phoric acid; another portion may be neutralised with ammonia, 
 and then treated with a mixture of sulphate of magnesia and 
 chloride of ammonium, which will precipitate any phosphoric 
 acid present, as ammonio-phosphate of magnesia. 
 
212 PHOSPHORUS. 
 
 When this method yields a distinct luminosity or furnishes 
 globules of phosphorus, it is certain that the poison was present 
 in its free state. Should, however, the phosphorus have already 
 undergone oxidation, this method will yield no evidence of its 
 presence. Under these circumstances, the remaining contents 
 of the flask are examined for oxides of phosphorus, in the 
 manner described hereafter. It must also be borne in mind, 
 that the luminosity may be entirely prevented by the presence 
 of certain volatile substances. These substances, however, 
 would not prevent any free phosphorus present from passing 
 over into the receiver, and there appearing at least in the form 
 of an oxide. That the luminosity of phosphorus is not readily 
 interfered with by the ordinary products of decomposition, is 
 shown by the following experiment. 
 
 The putrid mass resulting from exposing a human stomach 
 with its contents, free from phosphorus, to the action of the air 
 for six weeks, was made into a thin paste by the addition of 
 water. Twenty-five hundred fluid-grains of this highly offensive 
 mixture, acidulated with sulphuric acid, were then distilled with 
 about the thirtieth part of a grain of phosphorus, added in a 
 finely divided state. Nearly as soon as the mixture reached 
 the boiling temperature, a very distinct phosphorescence ap- 
 peared within the condenser, and continued without interruption 
 for twenty-six minutes, when the contents of the flask having 
 become very thick and black, the distillation was discontinued. 
 The distillate thus obtained measured nearly eighteen hundred 
 fluid-grains, had a milky appearance, and very ofi'ensive odor, 
 but no odor or globules of phosphorus were detected. When, 
 however, this liquid was treated with a few drops of nitric 
 acid, and evaporated to a small volume, then neutralised with 
 ammonia and treated with a mixture of sulphate of magnesia 
 and chloride of ammonium, it gave a fine crystalline precipitate, 
 which when further examined was found to represent very 
 nearly the fiftieth part of a grain of phosphorus. 
 
 Method of Lipowitz. — If in the application of this method, 
 the suspected mixture, after the addition of the fragments of 
 sulphur, be boiled in a retort with a long neck, or the latter 
 be connected with the receiver by means of a glass tube, and 
 
SEPARATION FROM ORGANIC MIXTURES. 213 
 
 the operation performed in the dark, the vapors as they pass 
 through the tube, if they contain phosphorus, will be phosphor- 
 escent, even, as we have in several instances found, when only 
 a very small quantity of the poison is present. In this manner, 
 this process may, as it were, be combined with that of Mit- 
 scherlich. Yet, as the poison would thus be divided, part of 
 it remaining in the retort with the sulphur and part passing 
 over into the receiver, this method is only advisable in the 
 absence of facilities for the application of Mitscherlich's 
 m.ethod, in which the whole of the poison may be collected in 
 the distillate. 
 
 Hydrogen Metliod. — A portion of the suspected mixture, 
 diluted with water if necessary, may be mixed in a test-tube 
 or small flask, with a few fragments of zinc and a quantity 
 of pure sulphuric acid equal in volume to about one-eighth of 
 the fluid present. Any phosphorus present will now be evolved 
 as phosphuretted hydrogen, which is luminous in the dark, and 
 yields a black precipitate with a solution of nitrate of silver. 
 The evolved gas may be ignited and the flame examined in 
 the manner already described {ante, p. 203). 
 
 Recovery as an Oxide of Phosphorus. — If the phosphorus has 
 undergone oxidation, the method of Mitscherlich, as already 
 stated, win fail to reveal its presence. But, if the poison has 
 only passed to the state of phosphorous acid, it may still be 
 detected by the hydrogen method, just mentioned. Should it, 
 however, have passed to the state of phosphoric acid, then this 
 method will also fail. 
 
 Under these circumstances, the mixture, after the addition 
 of water, and filtration if necessary, is treated with a few drops 
 of nitric acid and concentrated to a Small volume. It is then 
 treated with slight excess of pure carbonate of soda, evaporated 
 to dryness, and the residue slowly heated to fusion, by which 
 the organic matter will be destroyed, while any phosphoric acid 
 present will remain as tribasic phosphate of soda. The residue 
 is then dissolved in a small quantity of water, and the solution 
 examined by the usual tests for phosphoric acid. If, however, 
 only a minute quantity of phosphoric acid be thus detected, 
 this in itself will be no evidence that the phosphorus originally 
 
214 PHOSPHORUS. 
 
 existed in its unoxidised state, since that acid in minute quantity- 
 is normally present in most organic mixtures. 
 
 Failure to detect the poison. — In fatal poisoning by phos- 
 phorus, as by most other substances, the whole of it may be 
 eliminated from the body previous to death, even when death 
 takes place with the usual rapidity. Then, again, as this 
 substance readily undergoes oxidation, it may thus, at least as 
 free phosphorus, speedily disappear from the dead body. In 
 Dr. Lewinsky's case, already cited, in which death occurred on 
 the sixth day, a chemical examination of the stomach and its 
 contents, by Dr. Schauenstein, failed to yield any indication of 
 the presence of phosphorus. So also, in a case reported by 
 Dr. Nitsche, in which a soldier purposely swallowed the ends 
 of six ordinary packets of phosphorus-matches and died on the 
 fourth day, a chemical examination of the stomach and a por- 
 tion of the intestines, with their contents, two days after death, 
 revealed no evidence of the presence of the poison. (Amer. 
 Jour. Med. Sci., Jan., 1858, p. 288.) Early in the history of 
 this case, a large quantity of the phosphorus mixture was 
 expelled from the stomach by vomiting. 
 
 Cases are reported, however, in which this poison was de- 
 tected after comparatively long periods. Thus, in a case quoted 
 by Wharton and Stille, it was detected in the contents of the 
 intestines on the tenth day after it had been taken; and in 
 another, cited by Dr. Taylor, it was found in its free state, in 
 the stomach of a body that had been buried fourteen days, and 
 which was in an advanced state of decomposition. And in a 
 case reported by Dr. Ludwig, in which a child, three years and 
 a half old, was poisoned by phosphorus-paste, about one grain 
 of phosphorus in substance, was obtained from the contents of 
 the stomach and intestines, although the body had been buried 
 three weeJcs. (Jour, de Chim. Med., 1863, p. 584.) This is the 
 longest period we find recorded after which the poison has yet 
 been detected. 
 
 Quantitative Analysis. — Any phosphorus found in its solid 
 state, or obtained by Mitscherlich's method, may, of course, be 
 weighed as such. When, however, the phosphorus has been 
 
QUANTITATIVE ANALYSIS. 215 
 
 converted into phosphoric acid, it may be determined as pyro- 
 phosphate of magnesia (2MgO; PO,,). For this purpose, the 
 solution is treated with slight excess of a clear mixture of 
 sulphate of magnesia, chloride of ammonium, and ammonia, and 
 allowed to stand for several hours, in order that the precipitate 
 may completely separate. The precipitate is then collected upon 
 a filter, washed with water containing a little ammonia, dried, 
 ignited, and after cooling, weighed. Every one hundred parts 
 of the ignited residue, if pure, correspond to sixty-four parts 
 of anhydrous phosphoric acid or twenty-eight parts of free 
 phosphorus. 
 
216 ANTIMONY. 
 
 OHAPTEE lY. 
 
 ANTIMONY. 
 
 History. — Antimony is a bluish-white, hard, brittle metal, 
 having a density of about 6-7 : its symbol is Sb, and its com- 
 bining equivalent, according to Schneider, 120-3. When heated 
 to near redness, it takes fire and burns with the evolution of 
 dense white fumes of teroxide of antimony. The metal is un- 
 acted upon by cold sulphuric acid, but the hot acid converts it 
 into an oxide with the evolution of sulphurous acid gas. Hot 
 concentrated nitric acid oxidises it chiefly into antimonic acid; 
 hydrochloric acid, even at the boiling temperature, has little 
 action upon it, but it is readily soluble in nitro-muriatic acid. 
 
 When taken in its pure state into the system, antimony 
 seems to be inert. But several of its preparations are more or 
 less poisonous. The only one of these, however, likely to be- 
 come the subject of a medico-legal investigation, is tartar emetic. 
 
 Taetae Emetic. 
 
 Composition. — This substance, known also as tartarised anti- 
 mony or tartrate of antimony and potash, is a combination of 
 potash, teroxide of antimony, and tartaric acid, with two equiv- 
 alents of water of crystallisation : KO, SbOj, C8H4O10, 2 Aq. 
 Teroxide of antimony, in its free state, is a white crystallisable 
 substance, which is insoluble in water, and only sparingly sol- 
 uble in nitric acid, but readily soluble in hydrochloric and tar- 
 taric acids, and in the caustic alkalies. The poisonous effects of 
 tartar emetic are entirely due to the presence of this substance. 
 
 Symptoms. — As a summary of the symptoms usually pro- 
 duced by tartar emetic, when swallowed in large quantity, may 
 be mentioned the following : nausea, violent and continuous 
 
PHYSIOLOGICAL EFFECTS. 217 
 
 vomiting, burning pain in the stomach and bowels, profuse 
 purging, great thirst, violent cramps, small and feeble pulse, 
 coldness of the extremities, great prostration, and in some in- 
 stances convulsions and deHrium. The matters discharged from 
 the bowels are usually very fluid, and frequently contain bile. 
 The urine is generally increased in quantity, and its passage 
 sometimes attended with pain. It is a remarkable fact that in 
 several of the reported instances of poisoning by this substance, 
 there was neither vomiting nor purging; in these, however, the 
 other symptoms were present in an aggravated form. 
 
 A man of strong constitution, aged fifty years, for the pur- 
 pose of self-destruction, swallowed about thirty-seven grains of 
 tartar emetic. Violent vomiting, excessive purging, and con- 
 vulsions soon ensued. On the morning of the third day, he 
 complained of violent pain in the epigastrium, which was miich 
 distended ; spoke with difficulty, and appeared as if intoxicated ; 
 the pulse was imperceptible. During the day the bowels be- 
 came tympanitic and more painful, and delirium supervened. 
 The next morning all the symptoms were aggravated, and in 
 the evening the delirium became furious ; convulsions then set 
 in, and death occurred during the night, nearly four days after 
 the poison had been taken. (Orfila's Toxicologic, 1852, vol. i, 
 p. 623.) 
 
 The following most remarkable case of recovery is reported 
 by Dr. J. T. Grleaves (Western Jour, of Med. and Surg., Jan., 
 1848, p. 23). A young man of strong constitution swallowed 
 a tablespoonful of tartar emetic (about an ounce). In an liour 
 and a half afterwards, although he drank freely of warm water 
 and repeatedly tickled his fauces with his finger, no vomiting 
 had occurred. During the first three hours he vomited only 
 two or three times, and the matter ejected was chiefly the warm 
 water taken to induce vomiting. Two hours after taking the 
 poison, there was violent involuntary purging, and he became 
 pulseless, speechless, and was apparently dying. Three hours 
 after the occurrence, when the case was first seen by Dr. 
 Gleaves, the breathing was slow and difficult, the face pale, 
 features shrunken, eyes fixed, pupils dilated, and the surface 
 cold; there was no pulse, and the patient was apparently 
 
218 ANTIMONY. 
 
 unconscious. In seven hours, the purging ceased, consciousness 
 returned, and there was great thirst, and a sense of burning 
 pain in the throat, oesophagus, stomach and bowels. Great irri- 
 tability of the stomach ensued, and the matters vomited were , 
 tinged with blood. On the evening of the following day, the 
 patient was again pulseless and speechless ; and the abdomen 
 was tympanitic and painful to the touch. The vomiting con- 
 tinued, but the purging was arrested. On the third day, there 
 was occasional vomiting, and the throat was sore and covered 
 with pustules ; there was also painful micturition, the urine 
 being copious and highly colored. On the fourth day, the 
 whole body was covered with genuine tartar emetic pustules. 
 After a few days these began to heal, and in about two weeks 
 the patient was perfectly well. 
 
 Period when Fatal. — A child, recovering from measles, died 
 in an hour from the depressing effects of three-quarters of a 
 grain of tartar emetic, prescribed as a medicine. In a case 
 reported by Dr. C. Ellis, an unknown quantity of the poison 
 proved fatal to a young lady, aged twenty-one years, in seven 
 hours. The symptoms were violent vomiting and purging, ac- 
 companied with a sense of burning in the mouth, dryness of the 
 throat, and great thirst. Death took place apparently from ex- 
 haustion, without convulsions or any cerebral symptoms. (Bos- 
 ton Med. and Surg. Jour., Dec, 1856, p. 400.) In a case 
 reported by Dr. PoUock, in which sixty grains of tartar emetic 
 had been taken, death occurred in ten hours (London Med. Gaz., 
 May, 1850, p. 801). In this instance, the patient, a robust, 
 healthy man, aged about thirty years, was very soon seized 
 with violent vomiting and retching. In two hours after the 
 poison had been taken, there was still violent retching, at short 
 intervals, and the man complained of heat and constriction in 
 the throat, and pain in the epigastrium ; the respiration was fre- 
 quent ; the skin covered with perspiration ; the pulse rapid and 
 small. In a few hours afterwards, the vomiting ceased, and the 
 ■ patient became insensible ; the respiration slow and labored, but 
 not stertorous ; pulse very rapid and almost imperceptible ; and 
 the power of swallowing had ceased. Death took place tran- 
 quilly, and without convulsions. 
 
FATAL QUANTITY. 219 
 
 The cases now cited are among the most rapidly fatal yet 
 reported. Instances are recorded in which death did not occur 
 until after the lapse of several days ; and Dr. Deutsch relates 
 a case, in which a woman, who took by mistake a scruple of 
 tartar emetic, was brought exceedingly low by its violent action, 
 and died in the course of a year in consequence of its irritant 
 effects upon the intestinal canal. (Wharton and Stille Med. 
 Jur., p. 553.) 
 
 Fatal Quantity. — Several instances are on record in which 
 very small doses of tartar emetic produced most violent symp- 
 toms. Thus in an instance related by Dr. A. Stille (Mat. Med., 
 ii, 346), a dose of not more than half a grain produced violent 
 vomiting and purging, and a state closely resembling the col- 
 lapse of cholera. The patient was an insane female, whose 
 general health, however, was perfect. Of thirty-seven cases of 
 acute poisoning by tartar emetic collected by Dr. Taylor, six- 
 teen proved fatal. Of the fatal cases, the smallest dose was in 
 a child, three-quarters of a grain, and in an adult, two grains ; 
 but in this case, there were circumstances which favored the 
 fatal operation of the poison. (On Poisons, p. 543.) In a case 
 related by Dr. C. A. Lee, a child a few weeks old, who swal- 
 lowed about fifteen grains of the salt, in solution, was seized 
 with violent vomiting and purging, attended with convulsions, 
 which soon proved fatal. (New York Med. and Phys. Jour., 
 No. XXX, p. 802.) Two cases have already been cited in which 
 thirty-seven grains and sixty grains riespectively, proved fatal 
 to healthy adults. 
 
 The following remarkable case of recovery is related by 
 Dr. McCreery : A physician swallowed half an ounce of tartar 
 emetic, put up by mistake for RocheUe salt. In about thirty- 
 five or forty minutes after taking the poison, he experienced 
 some nausea, which ia about five minutes more was succeeded 
 by vomiting. Copious draughts of green tea and large doses of 
 tannin were then administered ; and these were followed by the 
 exhibition of albumen and an infusion of flaxseed. But the 
 vomiting, which was very distressing, continued with little inter- 
 mission for several hours. There was also very severe purging, 
 with most violent cramps of the legs, and slighter ones of the 
 
220 ANTIMONY. 
 
 wrists. The first evacuation from the bowels was purely serous ; 
 those which followed were of a bilious character, but very loose : 
 there were no cramps of the stomach. These symptoms gradu- 
 ally subsided, and after several days the patient was quite well. 
 (Amer. Jour. Med. Sci., Jan., 1853, p. 131.) It is well known 
 that in certain inflammatory diseases, tartar emetic may be ad- 
 ministered in very large doses without producing any of its 
 ordinary effects. 
 
 Treatment. — If there is not already free vomiting, it should 
 be promoted by the administration of large draughts of warm 
 water ; or the stomach may be emptied by means of the 
 stomach-pump. As a chemical antidote, various vegetable 
 astringents, such as a strong infusion of Peruvian bark, green 
 tea, nut-galls, or of oak-bark, have been highly recommended ; 
 and instances are reported in which their exhibition was appar- 
 ently attended with very great advantage. It has, however, 
 been denied that these substances serve to neutralise the poison. 
 
 After the poison has been expelled from the stomach, opium 
 may be administered to check the excessive vomiting. For 
 this purpose, a strong decoction of coffee has also been highly 
 recommended. 
 
 PosT-MOETEM APPEARANCES. — In the case cited from Orfila, 
 which proved fatal in about four days, the mucous membrane 
 of the stomach, except near the gullet, where it was healthy, 
 was red, tumefied, and covered with a viscid coating, which 
 was easily separated; the duodenum was in a similar condition, 
 but the other intestines were healthy. The intestines were 
 entirely empty. The brain was congested and softened. The 
 organs of the chest were healthy. 
 
 In the case related by Dr. Lee, in which fifteen grains 
 of the poison had been taken, the mucous membrane of the 
 stomach was red and softened, and on holding it up to the light, 
 it appeared of a bright crimson color. The stomach contained 
 a smaU quantity of slimy mucus, and, like the mucous mem- 
 brane, was softened. The texture of the cardiac orifice seemed 
 more changed than that of the pyloric. The duodenum was of 
 a deep brown color, almost livid, and contained the same kind of 
 substance as found in the stomach. The inflammation extended 
 
CHEMICAL PROPERTIES. 221 
 
 no further than the colon. The vessels of the scalp, as well as 
 those of the brain, and the right side of the heart, were dis- 
 tended with blood. The ventricles of the brain were half filled 
 with fluid, and there was effusion between the pia-mater and 
 arachnoid membranes. 
 
 In Dr. Ellis' case, thirty-nine hours after death, the body 
 was quite rigid, and there was considerable bluish discoloration 
 about the back of the neck and the hands. The stomach con- 
 tained a quantity of gruel-like, acid liquid, in which a consider- 
 able quantity of antimony was found. No well-marked morbid 
 appearances were detected in any of the abdominal organs. 
 The brain was not examined. 
 
 Chemical Peoperties. 
 
 General Chemical Nature. — Tartar emetic, as found in 
 the shops, is usually in the form of a white amorphous powder. 
 In its pure state it crystallises in large, transparent, odorless 
 octahedrons, having a rhombic base. The crystals are slightly 
 efflorescent at ordinary temperatures, and when heated to 212°, 
 become anhydrous. 
 
 When heated in a reduction-tube, by the flame of a spirit- 
 lamp, tartar emetic readily blackens, from the decomposition of 
 the organic acid, and is soon reduced to a mixture of charcoal 
 and metallic antimony. It undergoes a similar change when 
 heated upon platinum-foil, quickly destroying the platinum in 
 contact with the heated mass. Heated on charcoal before the 
 blow-pipe flame, the charred mass burns with the production 
 of a widely difiiised incrustation, the thicker portions of which 
 have a whitish color, while the thinner ones have a bluish 
 appearance; at the same time, it yields globules of metallic 
 antimony, which boil and are slowly dissipated by the continued 
 action of the heat. If the globules are allowed to cool, they 
 will be found exceedingly brittle. 
 
 According to R. Brandes, tartarised antimony is soluble in 
 from twelve to fourteen parts of water at the ordinary temper- 
 ature, and in less than three parts of boiling water. From 
 a warm saturated solution, the salt separates on cooling, in 
 
222 ANTIMONY. 
 
 beautiful bold crystals, Plate IV, fig. ^ 4. The same crystals 
 separate when one grain of a 1,000th or stronger solution of 
 the salt is allowed to evaporate spontaneously to dryness; from 
 more dilute solutions, the residue is usually destitute of any 
 well-defined crystals. Aqueous solutions of tartar emetic are 
 colorless, have a nauseous, metallic taste, and a feeble acid 
 reaction, even when the liquid contains only the 1,000th part 
 of its weight of the salt. These solutions after a time undergo 
 decomposition, the organic acid giving rise to a filamentous 
 growth: we have found this formation make its appearance, 
 after several days, in solutions containing even less than the 
 50,000th part of their weight of the antimony compound. 
 
 It is insoluble in alcohol. If this liquid be added to an 
 aqueous solution of tartar emetic containing even something 
 less than the 100th part of its weight of the salt, the latter is 
 precipitated in the form of plumose crystals; sometimes, how- 
 ever, the precipitate also contains octahedral crystals. 
 
 Special Chemical Properties. — When tartar emetic in its 
 solid state is moistened with a solution of sulphuret of ammo- 
 nium or of sulphuretted hydrogen, it immediately acquires an 
 orange-red color, due to the production of a sulphuret of anti- 
 mony. This reaction is peculiar to antimony, and will manifest 
 itself with the least visible quantity of the salt. Even the 
 residue left on evaporating one grain of liquid containing only 
 the 10,000th part of a grain of the pure salt, will yield a very 
 satisfactory coloration. 
 
 In the following investigations in regard to the special reac- 
 tions of reagents with solutions of tartar emetic, pure aqueous 
 solutions of the salt were employed. The fractions employed 
 indicate the amount of teroxide of antimony (SbOa) present in 
 one grain of the solution. The amount of tartar emetic repre- 
 sented in these cases, may be readily obtained by multiplying 
 the fractions by 2-35. 
 
 1. Sulphuretted Hydrogen. 
 
 From somewhat strong normal solutions of tartar emetic, 
 this reagent throws down a deep orange-red precipitate of 
 
SULPHURETTED HYDROGEN TEST. 223 
 
 tersulphuret of antimony (SbSj); in more dilute solutions, it 
 produces an orange-red turbidity, but no precipitate, at least 
 for several hours. The formation of the precipitate from dilute 
 solutions is much facilitated by heat. From solutions acidulated 
 with hydrochloric acid, however, even when very dilute, the 
 reagent produces an immediate precipitate. 
 
 The precipitate is insoluble in diluted hydrochloric acid; 
 but the hot concentrated acid readily decomposes it with the 
 formation of terchloride of antimony and the evolution of sul- 
 phuretted hydrogen gas. Fuming nitric acid converts it into 
 a white insoluble compound of antimony. It is readily soluble 
 in the fixed caustic alkalies, but insoluble in ammonia: at least 
 we find that when one part of the moist precipitate is frequently 
 agitated for some days with 10,000 parts of ammonia solution, 
 it does not entirely disappear; and that one part with even 
 25,000 parts of ammonia requires some hours for solution. 
 When dried and fused with nitrate of soda, it gives rise to 
 antimoniate and sulphate of soda. 
 
 In the following examination in regard to the limit of this 
 test, five grains of the antimony solution, placed in a small 
 test-tube, were acidulated with hydrochloric acid, and then 
 treated with the reagent. 
 
 1. 100th solution of teroxide of antimony (=-2V grain SbOs), 
 
 yields a very copious, light orange-red precipitate. Solu- 
 tions of tartar emetic as strong as this require about half 
 their volume of hydrochloric acid to redissolve the precip- 
 itate first produced by the acid. When tartaric acid is 
 employed as the acidifying agent, the precipitate produced 
 by the sulphur reagent has a much deeper red color than 
 when produced in the presence of hydrochloric acid. 
 
 2. 1,000th solution: an immediate precipitate, which very soon 
 
 becomes quite abundant. A normal solution of tartarised 
 antimony of this strength, yields with the reagent a deep 
 orange solution, but no precipitate, even after standing 
 twenty-four hours. 
 
 3. 10,000th solution: an immediate turbidity, and after a little 
 
 time a good deposit. If the mixture be warmed, the pre- 
 cipitate separates almost immediately. When the solution 
 
224 ANTIMONY. 
 
 is acidulated with tartaric acid, the precipitate requires 
 several hours for its separation. 
 
 4. 25,000th solution: in a very little time the mixture acquires 
 
 an orange tint; and after several hours there is a satisfac- 
 tory deposit. 
 
 5. 50,000th solution: in a little time the liquid assumes a yellow 
 
 tint, then a reddish hue, and after several hours yields a 
 quite perceptible orange-yellow deposit. 
 
 6. 100,000th solution: after some minutes the liquid acquires a 
 
 faint yellow tint, but undergoes no further change for at 
 least several hours. 
 
 The reaction of this reagent, as already intimated, is quite 
 characteristic of antimony. If the precipitate be dissolved in 
 hot hydrochloric acid, and the solution after cooling treated 
 with several times its volume of water, it yields a white pre- 
 cipitate, consisting of teroxide and terchloride of antimony, 
 which after a time becomes crystalline, and is readily soluble 
 in tartaric acid. 
 
 Sulphuret of Ammonium^ also, throws down from compara- 
 tively strong normal solutions of tartar emetic a precipitate of 
 tersulphuret of antimony, which is soluble in excess of the 
 reagent. In five grains of a 1,000th solution of teroxide of 
 antimony, the reagent produces a good, yellow-orange deposit. 
 In more dilute solutions, it fails to produce a precipitate, but 
 communicates to the liquid an orange or yellowish-red color. 
 In the presence of a free acid, however, it precipitates even 
 highly dilute solutions of the salt. 
 
 2. Acetate of Lead, 
 
 This reagent produces in normal solutions of tartar emetic 
 a white amorphous precipitate of tartrate of antimony and lead 
 (PbO, SbOs, CgH^Oio), which is readily soluble in acetic and 
 tartaric acids, and decomposed by nitric acid with the produc- 
 tion of a white flocculent deposit. 
 
 1. xoo" grain of teroxide of antimony, as tartar emetic, in one 
 
 grain of water, yields a very copious precipitate. 
 
 2. i.Joo grain: a very good flocculent precipitate. 
 
ZINC AND COPPER TESTS. 225 
 
 3. 10.0 grain, yields a very satisfactory deposit. 
 ^•' -2 s'.oT) grain: after a little time, the mixture becomes quite 
 turbid. 
 Acetate of lead also produces white precipitates in solutions 
 of various other substances. But the antimony deposit differs 
 from all these in that when washed and moistened with sul- 
 phuret of ammonium, it immediately assumes an orange-red 
 color ; after a little time however this color changes to a dark 
 brown or nearly black hue. 
 
 3. Metallic Zinc. 
 
 When a drop of a solution of tartar emetic is placed on a 
 piece of platinum-foil and acidulated with a small drop of 
 hydrochloric acid, the addition of a fragment of zinc causes 
 the separation of metallic antimony, which adheres to the plati- 
 num covered by the liquid, forming a black or brownish stain 
 (Fresenius). The deposit is readily soluble in warm nitric acid, 
 and when washed and dried, easily dissipated by heat. 
 !• Too" grain of teroxide of antimony, in solution in one grain 
 
 of water, when treated in the above manner, yields a very 
 
 copious, deep black deposit. 
 3. 1,0 grain: a very good deposit. 
 
 3. 5,000 grain: after a very little time, there is a very satisfac- 
 
 tory dark-brown stain. 
 
 4. 10,000 grain: after a few minutes, a very distinct brownish 
 
 stain makes its appearance. 
 The antimonial nature of these deposits may be shown, 
 by moistening the washed stain with nitric acid, and evapo- 
 rating to dryness at a gentle heat, when the residue, on being 
 touched with sulphuret of ammonium, will assume an orange- 
 red color. 
 
 4. Metallic Copper. 
 
 When a solution of tartar emetic is acidulated with hydro- 
 chloric acid, and boiled with a slip of bright copper-foil, the 
 antimony compound undergoes decomposition with the deposition 
 of metallic antimony upon the copper, in the form of a violet or 
 
 15 
 
226 ANTIMONY. 
 
 grey coating, the color depending upon the thickness of the de- 
 posit. It is obvious that the thickness of the deposit produced 
 by a given quantity of the metal, will depend on the size of 
 the copper-foil employed in the experiment. 
 
 When one grain of the tartar emetic solution, placed in a 
 thin watch-glass, is acidulated and heated with a very minute 
 portion of the foil, it yields as foUows : 
 
 !• TTo grain of teroxide of antimony: the copper immediately 
 assumes a violet color, and soon receives a thick, dark- 
 grey coating. 
 
 2- 1,0 grain, yields much the same results as 1. 
 
 3- 1 ,0 o Ti grain: in a little time, the copper presents a beautiful 
 
 violet color. 
 4. 5-o75"o"o grain, yields a very distinct reaction. 
 5- 10 0% grain : when the liquid is evaporated to near dry- 
 ness, the copper acquires a perceptible violet tarnish. 
 
 The production of a metallic deposit upon copper under the 
 above conditions, is common to antimony, arsenic, mercury, and 
 some few other metals. The violet color of the antimony de- 
 posit is rather peculiar ; but the deposit from this metal does 
 not always present this color, and, moreover, very thin deposits 
 of arsenic may present a similar hue. When the coated copper 
 is washed, dried, and heated in a narrow reduction-tube, the 
 antimony deposit, if present in comparatively large quantity, 
 yields a white amorphous sublimate. Arsenic under similar 
 circumstances yields a sublimate of octahedral crystals ; and 
 that from mercury appears in the form of minute metallic glob- 
 ules. The other metals referred to, fail to yield a sublimate 
 when thus treated. 
 
 The true nature of the antimony deposit may be shown, 
 as first advised by Mr. Watson, by boiling the coated copper 
 in a dilute solution of caustic potash, the coated metal being 
 occasionally withdrawn from the liquid and exposed to the 
 air, to favor the oxidation of the antimony, when after a 
 time the deposit will be entirely dissolved, as antimoniate of 
 potash. On now removing the copper-foil, and acidulating the 
 liquid with hydrochloric acid, concentrating to a small volume, 
 and then treating it with sulphuretted hydrogen, pentasulphuret 
 
HYDROGEN TEST. 
 
 227 
 
 of antimony, of an orange-red color, will be precipitated. This 
 method will serve to identify even very small deposits of the 
 metal. 
 
 5. Antimonuretted Hydrogen. 
 
 When a solution of tartar emetic, or of any of the soluble 
 salts of antimony, is mixed with zinc and sulphuric acid, in the 
 proportion to evolve hydrogen, the salt is decomposed and the 
 antimony evolved as antimonuretted hydrogen gas (SbHj). This 
 decomposition may be effected in the apparatus of Marsh, first 
 devised for the detection of arsenic. Fig. 3. 
 
 Fig. 3. 
 
 Apparatus for the detection of Antimony. 
 
 Pure zinc, and sulphuric acid, previously diluted with about 
 four volumes of water, are placed in the flask A, which is fur- 
 nished with a drying-tube c, and a reduction-tube d, the latter 
 of which is of hard glass and made to terminate in a drawn-out 
 point. The drying-tube should be loosely filled with cotton 
 
228 ANTIMONY. 
 
 containing fragments of chloride of calcium. When only a 
 minute quantity of antimony solution is to be examined, the 
 glass flask may be replaced by a test-tube. After the appa- 
 ratus has become completely filled with hydrogen, a small quan- 
 tity of the antimony solution is introduced into the flask, by 
 means of the funnel-tube a, when in a few moments the evolved 
 gas will contain antimonuretted hydrogen, the presence of which 
 may be shown by three diff'erent methods. 
 
 1. If the gas as it escapes from the end of the reduction- 
 tube be ignited, it burns with a bluish flame, and, unless the 
 amount of antimony present is very minute, evolves white fumes 
 of teroxide of antimony. If these fumes be received upon a 
 cold surface, as a piece of porcelain, they yield a white amor- 
 phous deposit, which immediately acquires an orange-red color 
 when moistened with sulphuret of ammonimn. If a piece of 
 cold porcelain, held in a horizontal position, be brought in 
 contact with the flame, the antimony will condense in the form 
 of a black, nearly circular spot or stain, which is usually sur- 
 rounded by a greyish ring ; as soon as a spot has thus formed, 
 the flame should be received upon a fresh portion of the por- 
 celain. 
 
 If the experiment be performed in a small apparatus, fifty 
 grains of a fluid mixture containing the 10,000th part of its 
 weight of teroxide of antimony (= -2So grain SbOg), will yield 
 quite a number of spots of the metal. 
 
 Antimony and arsenic are the only metals that under the 
 above conditions will yield metallic spots upon a cold surface. 
 The spots from these two metals usually difl'er somewhat in 
 regard to their physical appearance, those from antimony being 
 usually dull, whereas those from arsenic have generally a bright 
 metallic luster. They differ greatly, however, in regard to some 
 of their other properties. Thus, the antimony stains are slowly 
 and with difficulty dissipated by the flame of a spirit-lamp, 
 whilst those from arsenic are readily volatilised. Again, the 
 antimony spots readily dissolve in yellow sulphuret of ammo- 
 nium, and the solution, even from very smaU stains, when gently 
 evaporated to dryness, leaves a red or orange-red residue of 
 sulphuret of antimony, which is soluble in strong hydrochloric 
 
HYDROGEN TEST. 229 
 
 acid, but insoluble in ammonia ; whereas, the arsenic stains dis- 
 solve but slowly in yellow sulphuret of ammonium, and the 
 solution leaves upon evaporation a yellow residue of sulphuret 
 of arsenic, which is insoluble in hydrochloric acid, but readily 
 soluble in ammonia. Moreover, the antimony stains are insol- 
 uble or dissolve with great difficulty in a solution of hypochlorite 
 of Kme or of soda, whilst the arsenic spots readily disappear 
 when touched with a solution of this kind. 
 
 2. When a portion of the reduction-tube is heated to red- 
 ness, the antimonuretted hydrogen passing through the tube is 
 decomposed with separation of metallic antimony, which, when 
 only in small quantity, is deposited within the tube wholly on 
 the inner side of the part to which the flame is directly ap- 
 plied, but when in larger quantity, on both sides of the flame. 
 Arsenic under like circumstances yields a somewhat similar 
 deposit ; but in this case, the whole of the metal is deposited 
 in the tube on the outer side of the part to which the flame is 
 applied. 
 
 A much smaller quantity of antimony will in this manner fur- 
 nish a deposit than will produce spots from the ignited jet upon 
 porcelain. Fifty grains of a mixture containing the 500,000th 
 part of its weight of teroxide of antimony (= m.^ooo grain SbOj), 
 when treated in a small apparatus, will yield a very distinct 
 brownish stain ; and a similar quantity of a 50,000th solution 
 will yield a very good brownish-black deposit, within the heated 
 tube. Deposits of the metal produced by this method, exhibit 
 the same chemical reactions as those produced on porcelain by 
 the ignited gas. 
 
 3. If the antimonuretted hydrogen be conducted into a solu- 
 tion of nitrate of silver, the whole of the antimony is precipi- 
 tated as antimonide of silver (Ag, Sb), in the form of a black 
 powder. The chemical reaction in this case is as follows : 
 SbHs + 3 AgO, NO5 = Ag3 Sb + 3 HO + 3 NO5. When only a mi- 
 nute trace of antimony is present, the whole of the precipitate 
 collects in the lower end of the delivery-tube, in the form of a 
 black ring. 
 
 This reaction is extremely delicate, and the method can be 
 applied with a much smaller quantity of fluid than either of 
 
230 ANTIMONY. 
 
 / 
 
 those just mentioned. When the operation is performed in a 
 small test-tube and the evolved gas conducted into a few drops 
 of the silver-solution, five fluid-grains of a 10,000th mixture 
 of teroxide of antimony will produce a quite large, black de- 
 posit, much of which remains in the end of the delivery-tube. 
 A similar quantity of a 50,000th mixture produces after sev- 
 eral minutes, a very satisfactory deposit; and a 100,000th 
 mixture will produce in about fifteen minutes, a very distinct 
 reaction. 
 
 Solutions of arsenic, sulphurets, and of several other sub- 
 stances, will also under similar conditions evolve gaseous com- 
 pounds, which produce black precipitates in a solution of nitrate 
 of silver. In the action of the arsenic compound, the precipitate 
 consists alone of metallic silver, the arsenic being oxidised into 
 arsenious acid, which remains in solution. 
 
 The true nature of the antimony precipitate, or antimonide 
 of silver, may be shown by collecting the deposit on a filter, 
 washing with warm water, and boiling with dilute hydrochloric 
 acid, in which the antimony will dissolve, while the silver will 
 remain in an insoluble form. If the quantity of precipitate 
 present is too minute to be separated from the filter, the portion 
 of the latter containing the deposit is boiled in the dilute hydro- 
 chloric acid. When the acid mixture has cooled and the deposit 
 completely subsided, it is transferred to a filter which has pre- 
 viouslybeen moistened with water, and the filtration repeated if 
 necessary, until the filtrate is perfectly clear. On now treating 
 the solution with sulphuretted hydrogen, tersulphuret of anti- 
 mony, of its peculiar color, wiU be thrown down. 
 
 Professor Hofmann has recommended to boil the washed 
 antimonide of silver with a solution of tartaric acid, in which 
 the antimony readily dissolves, while the silver remains un- 
 changed ; the solution is then filtered and treated with sulphu- 
 retted hydrogen. (Quart. Jour. Chem. Soc, April, 1860, p. 79.) 
 By either of the methods now considered, an exceedingly minute 
 quantity of antimony may be recovered from the silver pre- 
 cipitate. 
 
 From what has already been stated, it is obvious that the 
 method under consideration will serve to detect antimony in the 
 
CHEMICAL PROPERTIES. 231 
 
 presence of arsenic, and the latter in the presence of the former. 
 And this may be effected even when the metals are present in 
 very minute and disproportionate quantities. 
 
 Antimonuretted hydrogen is also decomposed by an alcoholic 
 solution of potash, with the production of a black precipitate. 
 Arsenic under similar conditions fails to produce a precipitate. 
 
 Other Reactions of Taetae Emetic. — Nitric acid produces 
 in somewhat strong solutions of tartar emetic, a white amorphous 
 precipitate, which according to Geiger, consists of a basic nitrate 
 of antimonic oxide. The precipitate is soluble only in very 
 large excess of the acid, but is readily soluble in tartaric acid ; 
 in solutions containing free tartaric acid, therefore, the reagent 
 fails to produce a precipitate. When the washed precipitate is 
 touched with sulphuret of ammonium, it immediately assumes 
 an orange-red color. One grain of a 100th solution of teroxide 
 of antimony when treated with a drop of the acid, yields a 
 quite copious deposit, which does not disappear on the further 
 addition of several drops of the reagent. One grain of a 1,000th 
 solution, yields with a smaU drop of the acid, a very fair pre- 
 cipitate. 
 
 Hydrochloric acid occasions in concentrated solutions of the 
 salt a white precipitate, which is much more readily soluble in 
 excess of the reagent than in the preceding reaction ; it is also 
 very readily soluble in tartaric acid. One grain of a 100th 
 solution of teroxide of antimony yields with a drop of the re- 
 agent a quite good precipitate, which disappears when the mix- 
 ture is stirred. This acid also produces white precipitates in 
 solutions of silver, lead, and of sub-combinations of mercury. 
 The silver precipitate is readily soluble in ammonia, and that 
 from mercury is turned black, whilst the precipitates from lead 
 and antimony are unchanged by this reagent. Sulphuret of 
 ammonium immediately changes the antimony precipitate to an 
 orange-red color, whilst it turns the lead-deposit black. The 
 antimony precipitate is the only one of these that is soluble in 
 tartaric acid. 
 
 SulpJiuric acid throws down from similar solutions, a white 
 amorphous precipitate, which becomes orange-red when touched 
 
232 ANTIMONY. 
 
 with sulphuret of ammonium. The production of a white pre- 
 cipitate by this acid is common to solutions of several other 
 metals. 
 
 Ammonia precipitates from solutions of tartar emetic, white 
 teroxide of antimony, which is insoluble in excess of the pre- 
 cipitant. One grain of a 100th solution of teroxide of antimony 
 yields a very good precipitate ; and a similar quantity of a 
 1,000th solution yields a quite fair, granular deposit, especially 
 if the mixture be stirred. Carbonate of ammonia fails to pro- 
 duce a precipitate, even in concentrated solutions of the anti- 
 monial compound. 
 
 Potash and Soda produce in quite concentrated solutions of 
 the salt, white amorphous precipitates, which are readily soluble 
 in excess of either reagent. The carbonates of these alkalies, 
 however, . throw down white precipitates that are insoluble in 
 excess of the precipitant ; the Kmit of these reactions is about 
 the same as that of ammonia. 
 
 When a solution of tartar emetic is treated with sufficient 
 excess of potash to redissolve the precipitate first produced, 
 and a solution of nitrate of silver then added, it produces a 
 brownish-black precipitate, consisting of a mixture of suboxide 
 and protoxide of silver, while the antimony remains in solution 
 as antimoniate of potash. If the precipitate thus produced be 
 treated with ammonia, the protoxide of silver is dissolved, while 
 the suboxide remains as a dense black powder. One grain of 
 a 10,000th solution of teroxide of antimony, when treated after 
 this method, will yield a very satisfactory black deposit ; and the 
 reaction is visible when a similar quantity of even a 25,000th 
 solution of the antimony compound is employed. Nitrate of 
 silver alone, produces in solutions of the antimony salt, a white 
 precipitate. 
 
 Corrosive sublimate slowly throws down from solutions of 
 the salt, even when quite dilute, a white flocculent precipitate. 
 Cliromate and bi-chromate of potash impart to very strong solu- 
 tions, a greenish color, and throw down a slight, greenish pre- 
 cipitate. Ferro- and ferri-cyanide of potassium fail to produce 
 a precipitate, even in concentrated solutions of the antimony 
 compoimd. 
 
SEPARATION FROM ORGANIC MIXTURES. 233 
 
 Sepaeation from Organic Mixtures. 
 
 Suspected Solutions. — The same method of analysis is equally 
 applicable for the examination of suspected articles of food or 
 drink, Tomited matters, and the contents of the stomach. The 
 mixture, after the addition of water if necessary, is acidulated 
 with hydrochloric acid, a little tartaric acid added, and the whole 
 exposed to a gentle heat for about fifteen minutes. When the 
 mixture has cooled, it is thrown upon a muslin strainer, the 
 strained liquid filtered, and the filtrate, after concentration if 
 necessary, exposed to a current of sulphuretted hydrogen gas 
 as long as a precipitate is produced, and then allowed to stand 
 in a moderately warm place for several hours, in order that the 
 precipitate may completely subside. 
 
 If antimony is present in comparatively large quantity, the 
 precipitate thus obtained wiU have a more or less orange-red 
 color ; if, however, the metal is present in only minute quantity, 
 or the deposit contains much organic matter, it wiU present a 
 yellow or brownish appearance. The precipitate is now col- 
 lected upon a filter, washed with water containing a little hydro- 
 chloric acid, then boiled with strong hydrochloric acid, w'hen 
 any tersulphuret of antimony will be decomposed and the metal 
 dissolved as terchloride. After solution has taken place, the heat 
 should be continued until the odor of the sulphuretted hydrogen, 
 evolved by the decomposition, has entirely disappeared. 
 
 A small portion of the clear liquid may now be examined 
 by the zinc and copper tests in the manner already described, 
 except that it is not necessary to add hydrochloric acid since 
 this is already present. Another portion of the liquid may be 
 treated with large excess of water, when the antimony, unless 
 present in only A-'ery minute quantity, will be precipitated as 
 white oxychloride, the true nature of which is fully established 
 by its assuming an orange-red color when moistened with sul- 
 phuret of ammonium, as weU as by its ready solubility in tar- 
 taric acid. Should these tests yield positive reactions and it be 
 desired to further pursue the investigation, the whole of the 
 antimony may be precipitated in the form of oxychloride, by 
 
234 ANTIMONY. 
 
 treating the hydrochloric acid solution with water, and the pre- 
 cipitate collected, washed, and then agitated for some time with 
 a very dilute solution of carbonate of soda. In this operation, 
 the oxychloride of antimony will be entirely converted into ter- 
 oxide of the metal, the chlorine being taken up as chloride of 
 sodium: care should be taken to employ only a very dilute solu- 
 tion of the soda-salt, since otherwise more or less of the anti- 
 mony compound might be dissolved. The precipitate is now 
 collected, washed, and digested at a moderate heat with a little 
 water containing an appropriate quantity of tartrate of potash, 
 or cream of tartar, when it wiU be dissolved as tartar emetic, 
 the presence of which may be determined by the usual tests. 
 
 Should the precipitate produced from the original solution 
 by sulphuretted hydrogen have a dark color, it should not be 
 concluded, from this fact alone, that the metal is entirely ab- 
 sent ; since it might be present even in very notable quantity, 
 and the peculiar color of its sulphuret entirely masked by the 
 presence of organic matter. 
 
 Under these circumstances, the washed precipitate, placed 
 in a thin porcelain dish, may be treated with a few drops of 
 concentrated nitric acid, and the mixture cautiously evaporated 
 to dryness, the operation being repeated if necessary until the 
 organic matter is well carbonised. Any antimony present will 
 now exist as an oxide of the metal. The residue is then moist- 
 ened with a few drops of a strong solution of potash, the liquid 
 expelled by a moderate heat, and the dry residue very gradu- 
 ally heated to fusion. The cooled mass is stirred with a little 
 water, the mixture acidulated with tartaric acid, then boiled 
 for some minutes, and the solution filtered. The whole of the 
 antimony will now be present in the filtrate, which, if the oper- 
 ations have been conducted with care, will be perfectly colorless. 
 A portion or the whole of the solution, may now be treated with 
 a few drops of hydrochloric acid and exposed to a current of 
 sulphuretted hydrogen, when any sulphuret of antimony thrown 
 down will exhibit its characteristic color. 
 
 By this method the sulphuret of antimony produced from 
 the 100th of a grain of the teroxide of the metal, may be 
 recovered from a very complex organic mixture without any 
 
SEPARATION FROM ORGANIC MIXTURES. 235 
 
 apparent loss. Should the final solution obtained by the above 
 method be highly colored, then instead of treating it with sul- 
 phuretted hydrogen, it may be mixed with zinc and diluted 
 sulphuric acid in the apparatus of Marsh, and the evolved gas 
 conducted into a solution of nitrate of silver, as long as a black 
 precipitate is produced. Any antimonide of silver thus obtained, 
 is collected on a small filter, and well washed ; the point of the 
 filter is then pierced and the precipitate washed, by means of a 
 jet of water from a wash-bottle, into a small dish, then boiled 
 with a little tartaric acid, the solution filtered, and, after con- 
 centration if necessary, examined in the usual manner. The 
 sulphuret representing the 100th of a grain of teroxide of anti- 
 mony, may be carried through both these processes, and still 
 yield perfectly satisfactory results. 
 
 Should it be desired in case the investigation for antimony 
 should fail, to provide for the detection of other poisonous 
 metals whose sulphurets are also precipitated from acidified 
 solutions by sulphuretted hydrogen, such as arsenic, mercury, 
 lead, and copper, the following method may be pursued. The 
 filter containing the washed and still moist precipitate is spread 
 out in a dish, the deposit well stirred with a solution of yellow 
 sulphuret of ammonium, and the solution filtered. As the sul- 
 phurets of antimony and arsenic are readily soluble in sulphuret 
 of ammonium, these metals if present would be in the filtrate, 
 while the sulphurets of mercury, lead, and copper, being insol- 
 uble in this menstruum, would remain on the filter, which should 
 therefore be reserved for future examination if necessary. The 
 ammoniacal filtrate is now evaporated to dryness, and the resi- 
 due treated with nitric acid and potash in the manner already 
 described. Any arsenic present would now exist as arsenate of 
 potash, and the solution when treated with sulphuretted hydro- 
 gen yield a yellow precipitate of pentasulphuret of arsenic. If 
 this metal was not present, and the mixture contained anti- 
 mony, the results already described would of course be ob- 
 tained. Should these two metals occur in the same solution, 
 they may be separated by treating the mixture with zinc and 
 sulphuric acid and receiving the evolved gas in a solution of 
 nitrate of silver, in the manner heretofore pointed out. 
 
236 ANTIMONY. 
 
 From the Tissues. — The investigations of Orfila, and others, 
 have shown that antimony, when taken into the stomach, is 
 rapidly absorbed by the blood and deposited in the tissues ; and 
 that the absorbed poison may be entirely eliminated from the 
 living body within a very few days, the elimination taking place 
 chiefly through the urine. Of the different tissues of the body, 
 the liver and kidneys usually contain the largest proportion of 
 the absorbed poison. 
 
 About one-third of the liver, cut into very small pieces and 
 placed in a porcelain dish, may be ma'de into a thin paste with 
 water containing about one-fifth of its volume of pure hydro- 
 chloric acid. The mixture is then exposed to a moderate heat, 
 with Sequent stirring and the occasional addition of small quan- 
 tities of powdered chlorate of potash, until the organic solids 
 have become entirely disintegrated. The cooled mixture is 
 transferred to a muslin strainer, and the organic matter left 
 upon the cloth well washed with water, the washings being col- 
 lected with the first-strained liquid ; the solution is then filtered, 
 the filtrate concentrated, allowed to cool, and if necessary again 
 filtered. The solution is now exposed for several hours to a 
 slow stream of sulphuretted hydrogen gas, after which it is 
 allowed to repose for about twenty-four hours, in order that the 
 precipitate may fully subside. Any precipitate thus obtained 
 is collected, charred by nitric acid, fused with potash, and the 
 residue examined in the manner described above. 
 
 For the recovery of absorbed antimony, Orfila recommended 
 to decompose the organic matter by nitric and sulphuric acids. 
 The tissue, cut into small pieces, is boiled with nitric acid, the 
 homogeneous mixture evaporated to dryness, and the residue 
 well charred with concentrated sulphuric acid. The dry car- 
 bonaceous mass is then boiled with hydrochloric acid containing 
 a few drops of nitric acid, when any antimony present will be 
 dissolved as chloride. The solution thus obtained is introduced 
 into the apparatiis of Marsh, and the evolved gas examined in 
 the usual manner. 
 
 Absorbed antimony may also be recovered by boiling the 
 finely 'divided tissue with pure hydrochloric acid diluted with 
 about six volumes of water, and introducing into the boiling 
 
QUANTITATIVE ANALYSIS. 237 
 
 mixture separate slips of bright copper-foil as long as they con- 
 tinue to receive a metallic coating. Only a small slip of the 
 copper should at first be employed. Should this after several 
 minutes fail to receive a deposit, it is removed from the mix- 
 ture and the boiling continued until the organic tissue is entirely 
 broken up. The cooled mixture is then strained, and the 
 strained liquid again boiled with a fresh slip of copper, the 
 boiling being continued if necessary until the liquid is evap- 
 orated to near dryness. It may be remarked that this method 
 would not apply to organic mixtures which had been prepared 
 by means of chlorate of potash, since the products of this salt 
 would prevent the deposition of the antimony. 
 
 Quantitative Analysis. — The solution, acidulated with hy- 
 drochloric acid, is treated with sulphuretted hydrogen gas as 
 long as a precipitate is produced, and the mixture gently 
 warmed until the supernatant liquid has become perfectly clear. 
 The precipitate is then collected on a filter of known weight, 
 washed, thoroughly dried on a water-bath, and weighed. Every 
 one hundred parts by weight of tersulphuret of antimony thus 
 obtained, correspond to 85-74 of the teroxide, or 202-85 parts 
 of pure crystallised tartar emetic. 
 
238 ARSENIC. 
 
 OHAPTEE Y. 
 
 ARSENIC. 
 
 I. Metallic Arsenic. 
 
 History and Chemical Nature. — By the term arsenic, the 
 chemist understands a certain simple or elementary form of 
 matter, having metallic properties; this term, however, is pop- 
 ularly applied to an oxide of the metal — arsenious acid. The 
 symbol for arsenic is As; and its combining equivalent 75. 
 According to Walchner, minute quantities of this metal are 
 present in all chalybeate waters and the deposits formed from 
 them, and in a great variety of ferruginous clays, marls, and 
 slates. (GmeKn's Hand-Book, vol. iv, p. 250.) The statement 
 formerly made by Orfila that arsenic occurred as a normal con- 
 stituent in the bones and muscles of animals, was afterwards 
 retracted as incorrect. 
 
 In its pure state, arsenic has a steel-grey color, a bright 
 metallic luster, and a density of about 5'8; it has a crystalline 
 structure, and is readUy reduced to powder, being very brittle. 
 It remains unchanged in dry air; but in the presence of moist- 
 ure, it slowly absorbs oxygen and assumes a duU dark-grey 
 appearance. When heated, it volatilises, without fusing, into a 
 colorless vapor, which on coming in contact with the air emits 
 a garlic-like odor; if strongly heated in the open air, it takes 
 fire and burns with a bluish flame and the evolution of dense 
 white fumes of arsenious acid. It is generally stated that 
 arsensic volatilises at a temperature of about 400° F.; but 
 according to the observations of Dr. J. K. MitcheU it requires 
 for this purpose a duU red heat. Hot sulphuric and nitric acids 
 oxidise and dissolve the metal, the former as arsenious and the 
 latter as arsenic acid. Hydrochloric acid has no action upon 
 it; but free chlorine converts it into chloride of arsenic. 
 
CHEMICAL PROPERTIES. 239 
 
 Physiological Effects. — Metallic arsenic, when taken into the 
 system, is capable of acting as a powerful poison; but, perhaps, 
 only in so far as the metal becomes oxidised and converted into 
 arsenious acid. From the experiments of Bayen and Deyeux, 
 and others, it would appear that the metal in its uncombined 
 state was inert. The substance sold in the shops under the 
 name of fly-powder, consists essentially of a mixture of metaUic 
 arsenic and arsenious acid, the latter usvially being present, it 
 is said, in the proportion of about five per cent. Numerous 
 instances of poisoning by this substance have occurred, chiefly, 
 however, as the result of accident. In a recent case of crim- 
 inal poisoning by fly-powder, in which we were consulted, death 
 took place in thirty-six hours; and although there had been 
 almost incessant vomiting for over thirty hours, a quantity of 
 arsenic equivalent to forty-two grains of arsenious acid remained 
 in the stomach at the time of death. The symptoms and morbid 
 changes produced by this substance are much the same as those 
 occasioned by arsenious acid. 
 
 Special Chemical Properties. — There is little difficulty in 
 recognising metallic arsenic. When volatilised in a narrow 
 reduction-tube, it condenses in the cooler portion of the tube, 
 forming a very characteristic sublimate. This sublimate usually 
 consists of two well-defined but conjoined parts, the lower of 
 which has a steel-like appearance, and when viewed on the 
 inside presents a crystalline structure, 
 resembling somewhat that of fractured 
 
 iron; the upper part of the deposit, ^---■^-- ---.^-^ -.-...^==,^^=^1.1 
 when viewed exteriorly, is destitute 
 of luster, and of a dark color, which 
 gradually fades into a light-grey mar- 
 gin, in which crystals of arsenious ^ 
 
 , , . n 1 TTTi 1 Tubes for Sublimation Of Arsenic. 
 
 acid are sometimes found. When the 
 
 sublimate is quite thin, it presents a brown appearance. On 
 the application of heat, the sublimate is readily chased up and 
 down the tube, and sooner or later becomes converted into 
 white, octahedral crystals of arsenious acid; this conversion is 
 much hastened if the closed end of the tube has been separated. 
 These reactions are peculiar to arsenic. 
 
240 ARSENIC. 
 
 If metallic arsenic be dissolved, by the aid of beat, in 
 strong nitric acid, and the solution evaporated to dryness, it 
 leaves a white residue of arsenic acid, which when moistened 
 with a strong solution of nitrate of silver, assumes a brick- 
 red color. A portion of the arsenic acid obtained by this 
 method, may be dissolved in water and submitted to the liquid 
 tests for this acid, mentioned hereafter; or, the solution may 
 be saturated with sulphurous acid gas, the excess of the gas 
 expelled by heat, and the solution then examined for arse- 
 nious acid. 
 
 Compounds of Arsenic. — Arsenic forms with oxygen, two well- 
 defined oxides, • namely, arsenious acid (AsOs) and arsenic acid 
 (AsOs). A lower, or suboxide, has also been described, but its 
 existence is doubtful. Arsenic unites with sulphur in several 
 proportions; the most important of these compounds are: bisul- 
 phuret of arsenic, or Realgar (ASS2), which has a ruby-red 
 color; tersulphuret of arsenic, or Orpiment (AsSg), having a 
 bright-yellow color; and pentasulphuret of arsenic (AsSs), the 
 color of which closely resembles that of orpiment. With hydro- 
 gen, the metal forms arsenuretted hydrogen (AsHj), which is a 
 colorless, highly poisonous, gaseous compound. Arsenic also 
 enters into various other combinations. 
 
 All- the soluble compounds of this metal, and such insoluble 
 combinations as undergo decomposition when taken into the 
 system, are poisonous. As a general rule, their activity in 
 this respect is in proportion to their solubility. Some of the 
 insoluble compounds as usually met with, not unfrequently con- 
 tain arsenious acid. This is the only compound of the metal 
 that will be considered in detail; in its consideration, however, 
 the chemical properties of several of the other compounds wUl 
 be very fully described. 
 
 11. Arsenious Acid. 
 
 Arsenious acid, commonly called white arsenic, and also 
 known as rats-bane, is a compound of one chemical equivalent 
 of arsenic with three equivalents of oxygen; its combining 
 equivalent is 99. It is readily obtained by volatilising metallic 
 
PHYSIOLOGICAL EFFECTS. 241 
 
 arsenic in a free supply of air. For commercial purposes, it 
 is usually prepared by roasting some one of the ores of the 
 metal in a reverberatory furnace communicating with large 
 chambers, in which the acid condenses. 
 
 This substance is found in the shops under two different 
 forms; either as a white or dull white, opake powder, or in the 
 form of large, hard masses. If recently prepared, these masses 
 are colorless, and transparent; but on exposure to the air, they 
 become opake, and of a white or yellowish-white color. This 
 change, from the transparent to the opake state, has been 
 ascribed to the absorption of moisture. Arsenious acid seems 
 to be nearly or entirely destitute of taste. ' At least, it has 
 frequently been swallowed in large quantity without any marked 
 taste being perceived; in other instances, however, its taste 
 has been variously described as sweetish, rough, hot, acrid, or 
 metallic. 
 
 Symptoms. — These are subject to great variation. Sooner 
 or later after a large dose of the poison has been swallowed, 
 there is usually a sense of heat and constriction in the throat, 
 with thirst, nausea, and burning pain in the stomach. The 
 pain becomes excruciating, and is attended with violent vomit- 
 ing and retching; the matters vomited present various appear- 
 ances, being sometimes streaked with blood, and at others of 
 a bilious character; the pain in the stomach is increased by 
 pressure. As the case progresses, the pain extends throughout 
 the abdomen, and there is generally severe purging, and tenes- 
 mus ; the matters passed from the bowels not unfrequently con- 
 tain blood. The thirst usually becomes very intense; in some 
 instances there is great difficulty of swallowing. The features 
 are collapsed and expressive of great anxiety; the pulse is 
 quick, small, and irregular; the eyes red; the tongue dry, and 
 furred; the skin cold and clammy, but sometimes hot; the 
 respiration difficult; and sometimes there are violent cramps 
 of the legs and arms. The urine is frequently diminished in 
 quantity, and its passage attended with great pain. Stupor, 
 delirium, paralysis, and convulsions have also been observed. 
 In many instances, death takes place calmly, and the intel- 
 lectual factilties remain clear to the last. 
 
 16 
 
242 ARSENIC. 
 
 Such are the symptoms usually observed in poisoning by 
 arsenic; but cases are reported in which the abdominal pain, 
 thirst, vomiting, and purging were either very slight or entirely 
 absent. In i^hese instances, the symptoms are usually not very 
 unlike those commonly observed in poisoning by a narcotic. 
 There is generally great prostration of strength, and faintness, 
 or even actual syncope; often convulsions, and sometimes dehr- 
 ium or insensibility. It was formerly believed that well-marked 
 gastric symptoms were absent only when a very large dose of 
 the poison had been taken; but this is by no means always 
 the case. 
 
 In a case of arsenical poisoning mentioned by Dr. Christi- 
 son, an individual expired in five hours without at any time 
 having vomited, although emetics were administered. The fol- 
 lowing case of this kind is reported by Mr. Fox. (London 
 Lancet, Nov. 4, 1848.) A stout, healthy young man, took a 
 teaspoonful of arsenious acid, mistaking it for flour. No marked 
 symptom of the action of the poison appeared for nearly six 
 hours afterwards, when purging suddenly supervened, and he 
 vomited two or three times. He then became drowsy; coun- 
 tenance sunken and livid; pulse rapid, and extremely feeble; 
 surface of the body cold, and watery stools of a greenish hue 
 passed involuntarily. He answered questions rationally, and 
 neither complained of pain, tenderness of the abdomen, tenes- 
 mus, nor any of the usual irritative symptoms of arsenical 
 poisoning. Soon afterwards he complained of dimness of sight, 
 laid down on the bed, and in a few minutes expired. 
 
 In most cases of acute poisoning by this substance, the 
 symptoms steadily run their course; yet sometimes there is a 
 remission or even an entire intermission of the more prominent 
 symptoms. This remission may extend through a period of 
 several hours, and the symptoms then return with increased 
 violence. The remission has even been repeated several times 
 in the same case. 
 
 Considerable variety has also been observed in regard to 
 the time within which the symptoms first manifest themselves. 
 In most instances, however, they appear in from half an hour 
 to an hour after the poison has been taken. In a case cited 
 
EFFECTS OF EXTERNAL APPLICATION. 243 
 
 by Dr. Beck, a woman, who had swallowed a quantity of the 
 poison mixed with' wine and an egg, experienced extreme dis- 
 tress immediately after taking the mixture. (Med. Jur., ii, p. 
 595.) In another instance, quoted by the same writer, twelve 
 persons in one family, were seized with symptoms immediately 
 after eating some soup containing the poison. Dr. Christison 
 quotes a case in which the symptoms appeared in eight min- 
 utes; and two others in which violent symptoms were present 
 in ten minutes after the poison had been taken. 
 
 On the other hand, instances are related in which the 
 symptoms were delayed much beyond the usual period. A 
 case of this kind, in which they did not appear for nearly six 
 hours, has already been cited. In a case related by Dr. Ryan, 
 where half an ounce of arsenic was taken in porter, the first 
 symptom, which was vomiting, did not occur until nine hours 
 afterwards. (Wharton and Stills, Med. Jur., p. 513.) A case 
 is also quoted by Dr. Taylor, from Belloc, in which ten hours 
 elapsed before any symptoms appeared. (On Poisons, p. 359.) 
 And Dr. Wood mentions an instance (U. S. Dispensatory, 
 1865, p. 26), related by Dr. E. Hartshorne, in which at least 
 a drachm of arsenious acid had been swallowed, and where the 
 symptoms of poisoning were delayed for sixteen hotirs. This 
 seems to be the most protracted case, in this respect, yet 
 recorded. 
 
 The external application of arsenic to abraded surfaces has 
 not unfrequently been followed by fatal results. In a case 
 reported by Dr. McCready, a wash composed of a mixture of 
 arsenious acid and gin, applied to the head of a child two 
 years old, affected with porrigo favosa, caused death in about 
 thirty-six hours. The most prominent symptoms were swelling 
 of the face, purging and tenesmus, with paralysis of the lower 
 extremities. No local inflammation was produced. Two other 
 children who were similarly treated, suffered with redness and 
 swelling of the face; but they speedily recovered. (Am. Jour. 
 Med. Sci., July, 1851, p. 259.) Dr. Christison cites an instance 
 in which the stearine of a candle containing arsenic, applied to 
 a blistered surface, produced local pain, nausea, pain in the 
 stomach, great thirst, redness of the tongue, spasms of the 
 
244 ARSENIC. 
 
 muscles of the lower extremities, weakness and irregularity of 
 the pulse, followed by death within twenty-four hours after the 
 application had been made. 
 
 Arsenic has also proved fatal when applied to the mucous 
 membrane of the vagina, and of the rectum, and when inhaled 
 in the form of vapor. In a case reported by Dr. Mangor, a 
 man poisoned three wives in succession by introducing arsenic 
 into the vagina. In at least two of these instances, the poison 
 produced its usual symptoms and death in twenty-four hours. 
 Within the last several years, numerous instances of chronic 
 poisoning by this substance have occurred from persons occu- 
 pying rooms hung with paper stained with Scheele's green, or 
 arsenite of copper. In these cases the results are due to por- 
 tions of the coloring matter becoming detached and inhaled. 
 
 Period tvhen Fatal. — In fatal poisoning by this substance, 
 death usually occurs in from twelve to thirty-six hours, after 
 the poison has been taken. Numerous instances, however, are 
 related in which death took place within a very few hours ; 
 while on the other hand, life has not unfrequently been pro- 
 longed for several days. The shortest period within which the 
 poison has yet destroyed life, seems to be two- hours ; and at 
 least three instances of this kind are on record. In a case 
 related by Dr. Dymock, death occurred in two hours and a 
 half; and Pyl relates another, which proved fatal in three hours. 
 (Christison on Poisons, p. 240.) Ninety grains of the poison 
 caused the death of a girl, aged fourteen years, in five hours. 
 Several instances are reported in which the patients recovered 
 from the primary action of the poison, and died from its second- 
 ary effects very long periods afterwards, even in one instance, 
 related to Wepfer, after the lapse of three years. 
 
 Fatal Quantity. — According to the observations of Prof. 
 Lachdse, of Angiers, a dose of from one to two grains of arse- 
 nious acid may prove fatal to a healthy adult ; a dose of from 
 a quarter to half a grain may induce symptoms of poisoning ; 
 and one-eighth of a grain may prove injurious. (Beck's Med. 
 Jur., vol. ii, p. 544.) In a case quoted by Dr. Taylor, two 
 grains of the poison, in the form of Fowler's solution, taken in 
 divided doses during a period of five days, destroyed the life of 
 
ANTIDOTES. 245 
 
 a woman. The same writer cites another instance, reported by 
 Dr. Letheby, in which two grains and a half killed a robust, 
 healthy girl, aged nineteen, in thirty-six hours. (On Poisons, 
 p. 377.) In a case mentioned by Dr. Christison, four grains 
 and a half caused the death of a child, four years old, in six 
 hours. 
 
 On the other hand, recovery has not unfrequently taken 
 place after very large quantities of the poison had been swal- 
 lowed. In a case recorded by Dr. Pereira, a man swallowed 
 half an ounce of powdered arsenic immediately after taking 
 his dinner, and the only effect produced was violent vomiting. 
 (Mat. Med., i, p. 632.) So also. Dr. A. Stille (Mat. Med., ii, 
 707) quotes the case of a woman who swallowed about a dessert- 
 spoonful of the poison immediately after a hearty meal, and 
 although vomiting did not occur, nor were any remedies admin- 
 istered for an hour and a half, yet within five days complete 
 recovery had taken place. 
 
 The following remarkable case is reported by Dr. W. C. 
 Jackson. (Am. Jour. Med. Sci., July, 1858, p. 77.) A young 
 man, aged twenty-eight years, took on an empty stomach not 
 less than two ounces of the poison. Nearly two hours after- 
 wards there was slight vomiting, with some traces of the 
 arsenic ; but the greater part of the poison was retained in 
 the body for six hours. Great irritability of the stomach then 
 ensued, with a burning sensation in this organ and in the throat. 
 This condition continued for about six hours, after which the 
 patient rapidly recovered. 
 
 Treatment. — This consists in the first place in the speedy 
 administration of an emetic ; or the stomach may be emptied 
 by means of the stomach-pump. As an emetic, sulphate of 
 zinc or of copper may be employed; if neither of these is at 
 hand, powdered mustard or a mixture of salt and water should 
 be administered, or vomiting may be induced by tickling the 
 throat with a feather. The vomiting should be assisted by the 
 free exhibition of demulcent drinks. For this purpose, a mix- 
 ture of milk and white of egg has been highly recommended. 
 If the poison has passed into the bowels, a dose of castor oil 
 may be highly useful. 
 
246 ARSENIC. 
 
 Of the various chemical antidotes that have been proposed 
 for arsenious acid, the hydrated sesquioxide of iron (FejO.,, 3 HO), 
 is much the most important. Drs. Bunsen and Berthold, in 
 1834, were the first to assert the antidotal properties of this 
 substance. When it is added to a solution of arsenious acid, 
 the latter is rendered wholly, or very nearly so, insoluble in 
 water. In support of this statement, we may adduce the fol- 
 lowing experiments. 1. One grain of arsenious acid, in solu- 
 tion, was agitated for a very little time with five grains of the 
 iron preparation suspended in half an ounce of water, and the 
 mixture quickly filtered. The filtrate was then examined and 
 found to contain less than the 100th part of a grain of the 
 poison. 2. When ten parts of the iron preparation were em- 
 ployed, and the filtrate concentrated to one hundred fluid-grains, 
 then acidulated with hydrochloric acid, and saturated with sul- 
 phuretted hydrogen gas, it failed to yield any distinct evidence 
 of the presence of the poison, even after standing at a moderate 
 temperature for several hours. These experiments do not, of 
 course, prove that the compound thus produced is insoluble in 
 the acid secretions of the stomach ; yet, the excess of the iron 
 preparation administered, might neutralise any free acid present. 
 
 The antidotal action of this substance seems to be due to 
 the sesquioxide of iron giving up a portion of its oxygen to the 
 arsenious acid, whereby the latter is converted into arsenic 
 acid, while the former is reduced to the protoxide of iron 
 (2Fe2 03 + As03=4FeO + As05). The arsenic acid thus pro- 
 duced, by uniting with a portion of the protoxide of iron, forms 
 an arsenate of iron, which, being insoluble, is inert. Theoret- 
 ically, therefore, one part of arsenious acid requires 2-15 parts 
 of the pure hydrated sesquioxide to render it inert. The anti- 
 dote should however be given in its moist state, and be admin- 
 istered in large excess. It is usually stated that about twelve 
 parts of the moist compound are required for one part of arse- 
 nious acid. 
 
 Hydrated sesquioxide of iron may be readily prepared by 
 precipitating the muriated tincture of the shops by an excess 
 of ammonia, collecting the precipitate on a muslin strainer, and 
 washing it with water until it no longer emits the odor of 
 
ANTIDOTES. 247 
 
 ammonia. A tablespoonful or more of the moist magma, mixed 
 with a little water, may be given as a dose. It should always 
 be freshly prepared. 
 
 In this connection, we may very briefly refer to some ex- 
 periments, kindly midertaken by Dr. Wm. Watt, with this 
 antidote upon poisoned dogs (For details, see Ohio Med. and 
 Surg. Jour., March, 1861). The action of the poison alone was 
 first determined upon five dogs of average size. To three of 
 these, six grains of arsfenious acid, in solution, were given to 
 each, and proved fatal in one hour and a half, five hours, and 
 six hours respectively. To the other two, three grains each 
 were administered, and caused death in six and eight hours 
 respectively. A solution of the poison was then administered 
 to twelve other dogs, and the dose followed — in some instances 
 immediately, in others in ten minutes, and in others still not 
 untU symptoms of poisoning had manifested themselves — by a 
 single dose of about two tablespoonfuls of the antidote, prepared 
 in the manner just described. After vomiting, in some instances 
 only once, but in others several times, all these animals recov- 
 ered, at most within several hours and without in any instance 
 suffering severe symptoms. Two of these dogs received three 
 grains ; two, four grains ; one, five grains ; three, six grains ; 
 two, seven grains ; and two, eight grains each of the poison. 
 In another experiment, six grains of the poison, in solution, 
 were .mixed with about fifteen parts by weight of the antidote, 
 and the mixture, after standing twenty minutes, given to a 
 dog; no appreciable effect whatever was observed, although 
 the animal was closely watched for many hours. This experi- 
 ment, therefore, indicates that the arsenate of iron is not readily 
 decomposed by the juices of the stomach. 
 
 Numerous instances are reported in which there seems to be 
 no doubt that this antidote was the means of saving life in the 
 human subject. Mr. Robson relates an instance of this kind, 
 in which more than a drachm and a half of the poison had been 
 swallowed, and the antidote was not administered until two 
 hours after the poison had been taken. In this case, about an 
 hour after the ingestion of the poison, the stomach-pump was 
 used, but unsuccessfully, on account of the instrument becoming 
 
248 ARSENIC. 
 
 choked with the remains of food. (U. S. Dispensatory, 1865, 
 p. 29.) It need hardly be remarked that the antidote can have 
 no effect upon any of the poison that has already entered the 
 circulation. 
 
 Post-mortem Appearances. — Great variety has also been 
 observed in regard to these, even in cases in which the symp- 
 toms during life were very similar. The lining membrane of 
 the throat and oesophagus has in some few instances been found 
 highly inflamed. The mucous membrane of the stomach is gen- 
 erally more or less reddened and inflamed; sometimes it has a 
 deep crimson color, at others it is of a deep brownish-red, and 
 it has presented a dark appearance, due to the effusion of 
 altered blood. This membrane is sometimes much softened, 
 and easily separated; and in some instances patches of it are 
 entirely destroyed. In other instances, however, it is much 
 thickened, and corrugated. The inflammation rarely extends 
 to the peritoneal covering of the stomach. When the poison 
 has been taken in the solid state, small particles of it are fre- 
 quently found adhering to the mucous membrane and cov- 
 ered with coagulated mucus. Ulceration of the stomach has 
 been of rare occurrence, except in protracted cases; how- 
 ever. Dr. Taylor observed it in a case that proved fatal in 
 ten hours. 
 
 In protracted cases, the intestines, particidarly the duode- 
 num and rectum, not unfrequently present signs of inflammatory 
 action similar to those found in the stomach. The lungs are 
 sometimes congested and inflamed; congestion of the brain has 
 also been observed. The blood throughout the body is usually 
 liquid, and of a dark color. Not a few instances of poisoning 
 by this substance are recorded in which after death no well- 
 marked morbid appearances were discovered in any part of the 
 body. This result has even been observed in cases in which 
 there were violent symptoms, and life was prolonged for many 
 hours. 
 
 Antiseptic Properties of Arsenic. — The preservative power 
 of arsenic when brought in direct contact with animal textures 
 is well known; and the poison seems to exert a similar action 
 when carried by means of the circulation to the different tissues 
 
PRESERVATIVE EFFECTS. 249 
 
 of the body. The bodies therefore of those who have died from 
 the effects of this poison are not unfrequently found in a good 
 state of preservation, even long periods after death. 
 
 We have elsewhere reported a case, described by Dr. 
 Douglas Day, in which this preservative action of the poison 
 was well marked in a body that had been buried seventeen 
 months. At this time, the body was destitute of odor, and 
 the flesh of the extremities had given place to a dark unctuous 
 matter. The abdominal walls were in a surprising state of 
 preservation and of the color of old parchment; the integu- 
 ments upon incision were firm, and the muscles of a pink hue, 
 but very attenuated. The omentum was large and in place, 
 and covered with saponaceous matter. The stomach and intes- 
 tines were pale, comparatively dry, and appeared as though the 
 convolutions had been pressed together; they were firm and 
 allowed free manipulation, and exhaled a peculiar but not offen- 
 sive odor. The liver, spleen, and pancreas appeared remark- 
 ably recent, and the posterior walls of the abdomen, the mesen- 
 tery and kidneys, were well preserved. The bladder also was 
 in a good state of preservation. A very notable quantity of 
 arsenic was detected in each of several of the abdominal organs : 
 no other parts were submitted to chemical examination. (Ohio 
 Med. and Surg. Jour., Nov., 1863.) 
 
 Dr. Christison quotes a case in which the body after being 
 interred seven years, was found entire. The head, trunk, and 
 limbs retained their situation; but the organs of the chest and 
 abdomen were converted into a brown soft mass, in which a 
 chemical analysis revealed the presence of a considerable quan- 
 tity of arsenic. 
 
 Although the bodies of those who died from the effects of 
 this poison have thus been found in an unusual state of pres- 
 ervation, yet this is by no means always the case, even when 
 the poison remains in the body at the time of death. In fact, 
 in some cases of arsenical poisoning, the process of putrefac- 
 tion seemed to advance with increased activity. At the same 
 time, it must be borne in mind that the body is sometimes 
 unusually preserved in cases in which death resulted from 
 ordinary disease or mechanical injury. 
 
250 ARSENIC. 
 
 Chemical Properties. 
 
 General Chemical Nature. — It has already been stated 
 that arsenious acid, in its amorphous state, occurs under two 
 varieties, known as the transparent and the opake. The spe- 
 cific gravity of the transparent variety seems to be some little 
 greater than that of the opake, the density of the former, 
 according to most observers, being about 3"75, and that of the 
 latter about 3'65. These varieties also differ in regard to their 
 solubility in water. Arsenious acid volatilises at a temperature 
 of about 380° F., into a colorless, odorless vapor, and recon- 
 denses on cold surfaces, principally in the form of regular octa- 
 hedral crystals. (For an excellent paper on the crystalline 
 forms of arsenious acid, by Dr. Guy, see Quart. Jour. Micro. 
 Science, July, 1861.) 
 
 Arsenious acid has only feebly acid properties; nevertheless 
 it readily unites with basic oxides forming salts, denominated 
 arsenites. These salts are readily decomposed by most other 
 acids. The arsenites of the alkalies are freely soluble in water; 
 but aU other arsenites are either only sparingly soluble or insol- 
 uble in this menstruum. The latter salts are readily decom- 
 posed and dissolved by nitric and hydrochloric acids. Upon 
 the application of heat, most of the arsenites undergo decom- 
 position. In this operation, the fixed alkaline arsenites retain 
 the greater portion of the arsenic, in the form of an arsenate. 
 When ignited with a reducing agent, all arsenites are decom- 
 posed with the evolution of metallic arsenic, in the form of 
 vapor. 
 
 Solubility. 1. In Water. — The degree of solubility of arse- 
 nious acid in water sometimes becomes a matter of considerable 
 importance in medico-legal investigations. The results of ob- 
 servers in regard to this point have been extremely discordant. 
 The exact quantity of the poison that will be taken up and 
 retained in solution by a given quantity of water, will depend 
 upon a variety of circumstances, among the principal of which 
 are the following: 1. The physical state of the acid; 2. The 
 relative proportions of the acid and water present; 3. Time 
 
SOLUBILITY IN WATER. 251 
 
 they have been in contact; 4. The temperature of the mixture; 
 . 5. If the mixture has been boiled, the length of time the boil- 
 ing was continued; and 6. The time that has elapsed since the 
 mixture was heated. Among numerous experiments that might 
 be cited showing the influence of these various conditions, the 
 following may be mentioned. 
 
 a. One part (50 grains) of finely powdered opaJce arsenious 
 acid was boiled with ten parts (500 grains) of distilled water 
 for one hour, the vaporised fluid being condensed and returned 
 to the flask as rapidly as formed, and thus the volume of the 
 fluid kept constantly the same. The solution was then filtered 
 as rapidly as possible, and a given portion of the filtrate evap- 
 orated to dryness on a water-bath. The residue thus obtained 
 indicated that one part of the acid had dissolved in 13"10 parts 
 of water. 
 
 h. A similar experiment with the transparent variety of the 
 acid, taken from the same mass as employed in experiment a, 
 gave a residue indicating that one part of the acid dissolved in 
 15'66 parts of water. According to Bussy, the transparent 
 variety is more soluble than the opake; Guibourt, however, 
 states that the reverse is the fact. 
 
 c. A similar experiment with the freshly sublimed crystallised 
 acid, indicated that one part of the acid had dissolved in 11'50 
 parts of water. 
 
 d. On repeating the last experiment and concentrating the 
 filtered solution to about half its volume, a white scum appeared 
 upon the surface of the liquid. The clear liquid was then 
 decanted and a given portion evaporated to dryness, when it 
 was found that one part of the acid had been held in solution 
 by 6 '72 parts of water. 
 
 e. After boiling one part of the crystallised acid, from the 
 sample used in experiment c, for one hour with ten parts of 
 pure water, without loss of liquid by evaporation, the mixture 
 was allowed to stand twenty-four hours. The solution then 
 contained one part of the acid in 5 8 "6 8 parts of water. 
 
 /. One part of the opaJce acid, from the sample used in 
 experiment a, was boiled for one hour with forty parts of water, 
 without loss of liquid by evaporation, and the solution quickly 
 
252 ARSENIC. 
 
 filtered. The filtrate contained one part of the acid in 43*7 
 parts of the menstruum. It wiU be observed that in this ex- 
 periment the conditions were the same as in experiment a, 
 except in the relative proportion of acid and water present. 
 Even when one part of the acid is boiled for an hour with one 
 hundred parts of water, a portion of the poison will still remain 
 undissolved. 
 
 g. One part of the opake acid was treated with twenty parts 
 of boiling water and the mixture frequently agitated for twenty- 
 four hours. The solution then contained one part of the acid 
 in 196 parts of water. 
 
 h. On treating the transparent variety of the acid in the 
 same manner as in the last experiment, the solution contained 
 one part' of the poison in 93 parts of the menstruum. On 
 comparing the experiments g and h with those of a and &, it 
 will be observed that under one set of conditions the transparent 
 acid dissolved more freely than the opake variety, whilst under 
 another the reverse was the case. 
 
 i. One part of the crystallised acid was frequently agitated 
 during nine days, at the ordinary temperature, with twenty 
 parts of pure water. The resulting solution contained one part 
 ' of the acid in 108 parts of water. 
 
 j. An experiment similar to the last and conducted at the 
 same time, with one part of the acid and five Jiundred parts of 
 water, yielded a solution which contained one part of acid in 
 810 parts of the menstruum. 
 
 The experiments now cited serve to explain, at least in a 
 measure, the discrepant statements of observers in regard to 
 the solubility of this substance. Furthermore, it is obvious that 
 unless something is known in regard to the conditions under 
 which the acid and liquid have been brought in contact, it will 
 be impossible to state even approximately how much of the 
 poison may have been dissolved, even by pure water. In gen- 
 eral terms, if the mixture contained one part of the acid to ten 
 or twelve parts of water and has been boiled and concentrated, 
 the liquid may hold in solution even as much as one-seventh of 
 its weight of the poison ; whilst on the other hand, if there was 
 very large excess of water and the mixture was not heated, the 
 
SOLUBILITY IN ALCOHOL AND CHLOROFORM. 253 
 
 liquid may not take up more than the 1,000th part of its weight 
 of the acid. 
 
 Gmelin placed pulverised, opake arsenious acid in various 
 proportions of water in closed bottles, and set them aside in a 
 cool place for eighteen years, with the following results. One 
 part of the acid in 1,000 parts of water : perfect solution. One 
 part of the acid in 100 _ parts of water: the solution contained 
 one part of acid in 102 parts of water. One part of acid in 
 35 parts of water : the solution contained one part of the acid 
 in 54 parts of water. (Hand-book of Chemistry, vol. iv, p. 
 257.) According to most observers, the solubility of the poison 
 is more or less diminished by the presence of most kinds of 
 organic matter. 
 
 2. In Alcohol. — One part of the crystallised acid, in the state 
 of powder, was frequently agitated for two days with twenty 
 parts of alcohol of specific gravity 0"802 (= 97"5 per cent.). 
 The solution thus obtained contained one part of acid in 2,000 
 parts of the menstruum. In a similar experiment with the 
 most common Idnd of whisky, one part of the acid dissolved in 
 880 parts of the liquid. 
 
 3. In Chloroform. — On frequently agitating powdered arse- 
 nious acid for two days with twenty parts by weight of pure 
 chloroform, two hundred grains of the filtered liquid contained 
 something less than the 1,000th part of a grain of the acid. 
 This experiment would, therefore, indicate that the acid required 
 more than 200,000 times its weight of chloroform for solution. 
 
 Absolute ether, under the conditions just mentioned, failed to 
 dissolve a trace of the poison. 
 
 Arsenious acid is readily soluble in solutions of the fixed 
 caustic alkalies, but it is much less soluble in ammonia. It is 
 also soluble in hydrochloric acid, and in certain of the vege- 
 table acids ; sulphuric acid dissolves it only in minute quantity. 
 Hot nitric acid oxidises and dissolves it to arsenic acid. 
 
 Of Solid Aesenious Acid. 
 
 1. If a small quantity of solid arsenious acid be thrown on 
 a piece of ignited charcoal or heated on a charcoal support in 
 
254 ARSENIC. 
 
 the reducing blow-pipe flame, it is dissipated in the form of 
 white fumes and emits a garlic-Uke odor. In this operation, 
 the arsenious acid first gives up its oxygen to the carbon form- 
 ing carbonic acid gas ; the metaUic arsenic thus set free is then 
 reoxidised by the air into arsenious acid, which is evolved and 
 gives rise to white fumes. The alliaceous odor emitted is due 
 to the reoxidation of the metal, and is only evolved when the 
 metal itself is being oxidised. It was formerly supposed that 
 this odor was peculiar to arsenic, but it is now known that 
 there are several other substances which possess a similar 
 odor. 
 
 2. When heated in a reduction-tube, arsenious acid volatil- 
 ises without fusing and recondenses in the cooler portion of the 
 tube, in the form of minute, octahedral crystals. Under the 
 microscope, this sublimate is quite peculiar, and the crystals 
 present the appearances illustrated in Plate IV, fig. 5. When 
 only a very minute quantity of the poison is thus sublimed, the 
 crystals are exceedingly small, but still perfectly characteristic. 
 Under an amplification of one hundred diameters, the angular 
 nature of a crystal that does not exceed the 8,000th part of an 
 inch in diameter may be readily recognised ; and with a power 
 of two hundred and fifty, crystals measuring only the 15,000tl:^ 
 part of an inch in size, may be satisfactorily determined. If 
 sufficient sublimate be obtained, the portion of the tube contain- 
 ing it may be boUed in a small quantity of pure water, and the 
 solution thus obtained, after concentration if necessary, exam- 
 ined by the liquid tests mentioned hereafter. 
 
 In applying this test to only a minute quantity of the poison, 
 the bore of the reduction-tube should not exceed the 16th part 
 of an inch in diameter. Or, after placing the arsenious acid in 
 a tube of this kind having thin walls, the tube may be carefully 
 heated at a little distance above the point occupied by the 
 poison, in a small blow-pipe flame, and drawn out into a capil- 
 lary neck; the poison is then sublimed into the contracted por- 
 tion of the tube. By this method the least visible quantity of 
 the poison wiU yield a very satisfactory sublimate ; at the same 
 time, this method permits the application of the higher powers 
 of the microscope, for the examination of the sublimate. 
 
REDUCTION-TEST. 255 
 
 Professor Guy recommends (Chem. News, vol. i, p. 200) to 
 heat the arsenious acid in a perfectly dry tube of small diam- 
 eter and about three-quarters of an inch in length and having 
 its mouth covered with a warm slide or disc of glass. The 
 crystals are deposited partly on the sides of the tube, but chiefly 
 on the glass cover. This method offers the advantage of having 
 the deposit upon a flat surface for examination by the micro- 
 scope I in point of dehcacy, however, it is very far inferior to 
 the preceding method. 
 
 In applying this sublimation-test to a suspected substance, 
 it must be borne in mind that there are other white powders, 
 besides arsenious acid, as salts of ammonia, oxalic acid, and 
 corrosive sublimate, which when heated in a reduction-tube may 
 yield a crystalline sublimate. But most, if not all, of these fal- 
 lacious substances melt before volatilising, and none of them 
 condense in the form of octahedral crystals. 
 
 3. Reduction-test. — If a small quantity of arsenious acid be 
 placed in the closed end of a narrow reduction-tube, or in the 
 end of a tube drawn out in the form shown in Fig. 5, and a 
 wedge of recently ignited charcoal, 6, 
 be placed in the tube a little distance 
 
 above the arsenical fragment or powder, ^ " J <r "STT--4..i^ 
 
 on heating the charcoal to redness by Tube for the reduction of Arseni- 
 the flame of a spirit-lamp and then ous Acid by charcoai. one-third 
 
 ■t r natural Bize. 
 
 slowly erecting the outer end of the 
 
 tube so that the flame may still heat the charcoal and at the 
 same time volatilise the arsenious acid, the latter will be deox- 
 idised in its passage over the ignited charcoal and yield a sub- 
 limate, c, of metallic arsenic. This reduction may also be 
 efi'ected by mixing the arsenious acid with a perfectly dry 
 mixture of powdered charcoal and carbonate of soda, and heat- 
 ing the whole in a plain or bulbed reduction-tube. 
 
 The sublimate thus obtained usually consists of two well- 
 defined parts, the lower of which has a bright mirror appear- 
 ance resembling polished steel ; while the upper has a darker 
 color, is destitute of luster, and is gradually lost in a light-grey 
 mist. The inner surface of the sublimate, especially of the 
 lower ring, presents a bright crystalline appearance. Sometimes 
 
256 ARSENIC. 
 
 the upper portion of the sublimate, when very thin, has a 
 brownish color. So also, sometimes its upper margin contains 
 crystals of arsenious acid. 
 
 If the closed end of the tube be removed and the sublimate 
 then heated, it is readily volatilised and oxidised into arsenious 
 acid, which condenses in octahedral crystals. The metallic 
 sublimate is soluble in a solution of hypochlorite of soda or of 
 lime. This confirmatory test may be applied by removing the 
 lower end of the tube, and then immersing the latter in a small 
 quantity of the soda solution; or, a few drops of the solution 
 may be drawn -into the tube, after the removal of its closed 
 end, by suction with the mouth. The upper portion of the 
 sublimate readily disappears when moistened with this liquid, 
 but the lower part requires some little time for solution ; some- 
 times the deposit becomes detached and drops out of the tube, 
 in the form of a metallic ring. The arsenical natiire of the 
 ■ sublimate may also be shown by dissolving it in a few drops 
 of warm nitric acid, evaporating the solution to dryness by a 
 moderate heat, and touching the residue with a drop or two of 
 a strong solution of nitrate of silver, when it will assume a 
 brick-red color, due to the formation of arsenate of silver. 
 
 One of the best methods yet proposed for the reduction of 
 solid arsenious acid, and which is equally applicable for arse- 
 nites and the sulphurets of arsenic, is by means of a ]ier- 
 fectly dry mixture of about equal parts of carbonate of soda 
 
 and cyanide of potassium. A small 
 portion of the arsenical compound is 
 
 # -._-^«-j^^S:_ _ -^- -_^ introduced into the bulb of a tube of 
 a, ° the form shown in Fig. 6, A, or of 
 
 ^^ 5 \ the form B as first proposed by Ber- 
 
 ^p-^-^ .■ rmj^iiiTTir^^^^ zelius, and covered with several times 
 "^ its volume of the above mixture. A 
 
 ^^^^^^^^^_^^^^C_^^ gentle heat is then apphed, first to 
 
 a- ° the neck of the tube and afterwards 
 
 Tubes for the leduction of Arsenious to the bulb J if in this Operation, any 
 
 moisture condenses within the tube, it 
 shovild be carefully removed. On now strongly heating the mix- 
 ture, the compound under examination will be reduced and yield 
 
FALLACIES OF REDUCTION-TEST. 257 
 
 a metallic sublimate, at about the point t. This reaction is ex- 
 tremely delicate, especially when performed in a Berzelius-tube. 
 
 When only a very minute quantity of the arsenical com- 
 pound is to be reduced, it may be placed in the closed end of 
 an ordinary reduction-tube, covered by the reducing mixture, 
 and the tube then heated at a little distance above the mixture, 
 in a blow-pipe flame, and drawn out into a contracted neck, as 
 represented in Fig. 6, C. After the neck of the tube has 
 cooled, the arsenical mixture is heated in the manner above 
 described. A mixture containing only the 1,000th part of a 
 grain of arsenious acid when treated after this method, in a. 
 tube having its neck contracted to about the 20th of an inch 
 in diameter, will yield a very satisfactory metallic . sublimate, 
 which upon resublimation further up the neck of the tube will 
 furnish several hundred crystals of arsenious acid, many of 
 them measuring the 1,000th of an inch in diameter. 
 
 As a reducing agent for arsenious acid, arsenites, and the 
 sulphurets of arsenic, as well as for other metallic compounds. 
 Dr. E. Davy, of Dublin, has recently recommended the ferro- 
 cyanide of potassium, or yellow Prussiate of potash, previously 
 dried at a temperature of 212°. (Chemical News, vol. iii, p. 
 288.) This salt has an advantage over the cyanide of potas- 
 sium, in that it does not readily absorb moisture from the 
 atmosphere. The arsenical compound is mixed with about six 
 or eight times its volume of the dried salt, and the mixture 
 fused in one or other of the reduction-tubes already described. 
 The mixture blackens before fusing. In point of delicacy, the 
 reaction of this reducing agent is quite equal to that of the 
 cyanide of potassium. > 
 
 Fallacies. — When, by either of the above methods of reduc- 
 tion, a metallic sublimate having the physical and chemical 
 properties described, is obtained, there is no doubt whatever 
 of the presence of arsenic. Compounds of mercury, cadmium,, 
 tellurium, and selenium may under similar circumstances yield 
 sublimates. These however may be readily distinguished from 
 the arsenical sublimate, even by the naked eye; under the 
 microscope, they would be found to consist of globules or drops.. 
 
 Moreover, neither of these sublimates when revolatilised will, 
 
 n 
 
258 ARSENIC. 
 
 like arsenic, furnish octahedral crystals; nor are they soluble 
 in a solution of hypochlorite of soda. Neither will they, when 
 dissolved in hot nitric acid and the solution evaporated to dry- 
 ness, leave a residue which assumes a brick-red color when 
 moistened with a solution of nitrate of silver. 
 
 It has also been stated, that a crust of charcoal or the 
 employment of a reduction-tube containing lead, might lead to 
 error; but it is difficult to conceive how either of these results 
 could be mistaken for an arsenical sublimate by any one at all 
 conversant with the physical appearances of the latter. Anti- 
 mony, which as we shall see hereafter is a source of fallacy 
 to some of the tests for arsenic, fails to yield a sublimate when 
 it or any of its compounds is exposed to the action of either of 
 the above reducing agents, in the manner described.. 
 
 Op Solutions of Arsenious Acid. 
 
 Pure aqueous solutions of arsenious acid have only a feeble 
 acid reaction. This reaction is common to both varieties of the 
 acid, and is still manifest in a solution containing only the 
 1,000th part of its weight of the poison. On allowing a drop 
 of a solution of this kind to evaporate spontaneously to dryness, 
 for convenience on a glass-slide, the acid will be left chiefly in 
 the form of white, octahedral crystals, which are readily dissi- 
 pated by heat. The residue thus obtained from ^he 100th part 
 of a grain of the acid, )vill usually contain many crystals that 
 measure the 1 ,000th of an inch in diameter. Equally sat- 
 isfactory results may be obtained from the 1,000th part of a 
 grain of the poison, but the crystals are usually quite small. 
 From the 10,000th part of a grain of the acid, the crystals are 
 very minute, but under the higher powers of the microscope 
 their true nature may be very satisfactorily determined. The 
 production of these octahedral crystals, completely vaporisable 
 by heat, is peculiar to arsenious acid. The dry residue thus 
 obtained may, of course, be examined by any of the tests 
 already mentioned for the poison in its solid state. 
 
 In the following investigations in regard to the behavior of 
 solutions of arsenious acid, solutions of the pure crystallised 
 
AMMONIO-NITRATE OF SILVER TEST. 259 
 
 acid were employed. The fractions indicate the amount of 
 anhydrous acid present in one grain of the sohition. The 
 results, unless otherwise stated, refer to the reactions of one 
 grain of the solution. 
 
 1. Ammonio-Nitrate of Silver. 
 
 This reagent is prepared by cautiously adding a dilute solu- 
 tion of ammonia to a solution of nitrate of silver, until the 
 merest trace of the precipitate first produced remains undis- 
 solved. It is- important that the proper quantity of ammonia 
 be added: since if there is deficiency, the reagent will also 
 produce yellow precipitates with solutions of the alkaline phos- 
 phates and silicates ; whilst, on the other hand, if there is 
 excess, it occasions no precipitate or only a partial one, with 
 arsenious acid. The reagent should always be freshly prepared. 
 Nitrate of silver alone produces at most only a slight turbidity 
 in solutions of free arsenious acid ; but with neutral arsenites, 
 it behaves in the same manner as the ammonio-nitrate with the 
 free acid. This test was first proposed, in 1789, by Mr. Hume, 
 of London. 
 
 Ammonio-nitrate of silver throws down from aqueous solu- 
 tions of arsenious acid a bright yellow precipitate of tribasic 
 arsenite of silver (3 AgO ; AsOj), which is readily soluble, to a 
 colorless solution, in ammonia and in nitric and acetic acids. 
 The precipitate is sparingly soluble in nitrate of ammonia, 
 but insoluble in the fixed caustic alkalies. Hydrochloric acid 
 decomposes it with the formation of white insoluble chloride of 
 silver. 
 
 1- Too" grain of arsenious acid, in one grain of water, yields 
 with the reagent a copious, bright yellow, amorphous pre- 
 cipitate, which after a little time becomes converted into 
 yellowish-brown crystals, of the forms illustrated in Plate 
 IV, fig. 6. The crystals closely adhere to the glass upon 
 which they have formed, and are insoluble in large excess 
 of ammonia and of acetic acid. 
 2. 1,0^0 grain, yields a rather copious precipitate, which partly 
 becomes crystalline. 
 
260 ARSENIC. 
 
 3. -swo grain : a quite good deposit, which remains amorphous, 
 grain : an immediate, yellowish turbidity, and in a 
 
 ^. 10,000 
 
 little time, small, yellow flakes. 
 5. 2' 5,o grain: after a little time," the mixture becomes very 
 distinctly turbid, and when viewed over a white surface, 
 as white paper, presents a slight yellow tint. Ten grains 
 of the solution yield an immediate yellowish turbidity, and 
 after a little time small flakes having a decided yellow 
 color. When examined in large quantity, solutions even 
 much more dilute than this, will yield very distinct re- 
 actions. 
 If the arsenite of silver thrown down by this reagent be 
 decomposed by slight excess of hydrochloric acid and the chlo- 
 ride of sUver separated by a filter, the clear acid filtrate will 
 yield with sulphuretted hydrogen gas, a bright yellow precipi- 
 tate of tersulphuret of arsenic, having the properties to be 
 pointed out hereafter. When the arsenite of silver is washed, 
 thoroughly dried, and heated in a reduction-tube, it undergoes 
 decomposition with the production of a sublimate of octahedral 
 crystals of arsenious acid ; when heated in a similar manner 
 with a reducing agent, such as ferrocyanide of potassium, it 
 yields a sublimate of metaUic arsenic. By either of these 
 methods, the arsenical nature of very minute quantities of the 
 silver-precipitate may be fully established. 
 
 Fallacies. — Ammonio-nitrate of silver also produces in solu- 
 tions of free phosphoric acid a yellow, amorphous precipitate, 
 which is readily soluble in nitric acid and in ammonia ; this 
 precipitate always remains amorphous. So, also, the reagent 
 produces a somewhat similar precipitate in solutions of free 
 vanadic acid ; but these solutions, unlike those of arsenious 
 acid, have a yellow color. Both free phosphoric and vanadic 
 acids, especially the latter, are extremely rare, and therefore 
 not likely to be met with in medico-legal investigations. The 
 properly prepared reagent fails to produce a precipitate in solu- 
 tions of the salts of either of these acids. Again, solutions of 
 the alkaline iodides and bromides yield with the reagent yellow- 
 ish precipitates ; but these precipitates are insoluble in dilute 
 nitric acid, and only slightly soluble in caustic ammonia. 
 
AMMONIO-SULPHATE OF COPPER TEST. 261 
 
 It need hardly be remarked that neither of the above pre- 
 cipitates, when dried and heated either alone or with a reducing 
 agent, in a reduction-tube, will yield ajj octahedral or metallic 
 sublimate. Neither of the above acids is a source of fallacy to 
 any of the other tests for arsenic. 
 
 Should arsenious acid and a chloride, as common salt, occur 
 in the same solution, the latter compound will yield with the 
 silver reagent a white precipitate of chloride of silver, which 
 will obscure the arsenical reaction. From a mixture of this 
 kind, the chlorine may be removed by treating the soltition, 
 after the addition of a drop of nitric acid, with slight excess of 
 pure nitrate of silver, and filtering. On now exactly neutral- 
 ising the filtrate with ammonia, the yellow arsenite of silver 
 will separate. 
 
 Since ammonio-nitrate of silver is decomposed with the 
 production of a precipitate, even iii the absence of arsenious 
 acid, by most organic solutions, the test is not applicable to 
 mixtures of this kind. 
 
 2. Ammonio- Sulphate of Copper. 
 
 This reagent is prepared by cautiously adding ammonia to 
 a somewhat dilute solution of sulphate of copper, until the pre- 
 cipitate first produced is very nearly all redissolved ; the clear 
 liquid is then decanted. The reagent produces in solutions of 
 arsenious acid a green, amorphous precipitate of arsenite of cop- 
 per, also known as Scheele's green. The precipitate is nearly 
 insoluble even in large excess of the precipitant, but readily 
 soluble in ammonia and in free acids. From very dilute solu- 
 tions of the poison, the precipitate does not appear of its char- 
 acteristic color, until the mixture has stood for some time. The 
 same precipitate is thrown down from solutions of neutral arsen- 
 ites, by sulphate of copper alone. 
 
 1. -Yo~» grain of arsenious acid, in one grain of water, yields 
 
 a very copious, yellowish-green precipitate, which when 
 washed acquires a bright green color. 
 
 2. TreSj-o grain : a rather copious, green deposit. 
 
 3. 575-00 grain : a good, bluish-green precipitate, which after a 
 
262 ARSENIC. 
 
 little time assumes a distinct green color, the blue tint 
 disappearing. The true color of these precipitates is best 
 seen when examined over a white surface. 
 4. 1 1) o "o grain : an immediate, bluish, flocculent • precipitate, 
 which after a little time acquires a Hght green color. The 
 precipitate from ten grains of the solution soon acquires a 
 fine green color. 
 Ten grains of a 25,000th solution of the acid, yield an im- 
 mediate, blue precipitate, which in a little time acquires a light 
 green hue. 
 
 Fallacies. — There is no other metallic substance, besides 
 arsenic, known, that yields with this reagent a similar precipi- 
 tate. But various organic substances yield with the reagent a 
 precipitate, having in some instances a color sbmewhat resem- 
 bling that of the arsenite of silver. So far, therefore, as the 
 mere production of a greenish precipitate is concerned, no reli- 
 ance whatever could be placed in the test when applied to 
 organic solutions. 
 
 The arsenical nature of the arsenite of copper may be shown, 
 by heating the dried precipitate, either alone or with a reducing 
 agent, in a reduction-tube, when it will yield a sublimate of 
 octahedral crystals of arsenious acid or of metallic arsenic, as 
 the case may be. When dissolved in hydrochloric acid and 
 boiled with a slip of bright copper-foil, arsenite of copper is 
 decomposed with the deposition of metallic arsenic upon the 
 copper-foil : the true nature of this deposit may be shown in 
 the manner to be described hereafter, under the consideration 
 of Reinsch's test. If the hydrochloric acid solution of the 
 arsenite be treated with sulphuretted hydrogen gas, it will yield 
 a brown or dark brown precipitate, consisting of a mixture of 
 the sulphurets of arsenic and copper. If this precipitate be 
 collected on a filter, washed, and then digested with ammonia, 
 the latter will dissolve the sulphuret of arsenic, while the sul- 
 phuret of copper will remain undissolved. On now filtering the 
 ammoniacal solution- and carefuUy neutralising it with hydro- 
 chloric acid, the sulphuret of arsenic will separate in the form 
 of a bright yellow precipitate. 
 
SULPHURETTED HYDROGEN TEST. 263 
 
 3. Sulphuretted Hydrogen. 
 
 Sulphuretted hydrogen gas, or Hydrosulphuric acid, throws 
 down from solutions of arsenious acid, previously acidulated 
 with hydrochloric acid, a bright yellow, amorphous precipitate 
 of tersulphuret of arsenic, or Orpiment, the reaction being : 
 AsOs + 3 HS = 3 HO + AsS,. For the application of this test, 
 a small quantity of sulphuret of iron may be introduced into an 
 ordinary gas-evolution flask and covered with pure water ; the 
 mouth of the flask is then closed by a cork having two per- 
 forations, one of which carries a funnel-tube, and the other, an 
 exit-tube bent twice at right angles. Sufficient sulphuric acid 
 is then added to the contents of the flask, by 
 means of the funnel-tube, to cause the evolu- 
 tion of a moderate stream of sulphuretted hy- 
 drogen ; this is conducted into the acidulated 
 arsenical solution, contained in a test-tube or 
 any convenient vessel. When the quantity of 
 material to be examined is very small, the ap- 
 paratus illustrated in Fig. 7, may be em- 
 ployed. From very dilute solutions of the 
 
 . . . , ., Apparatus for detectiug 
 
 poison, the precipitate does not separate, until Arsenic hySuiphuret- 
 the excess of the reagent added is expelled by " ' ^°e'"^- 
 
 a gentle heat or by exposure to the air. In all cases, a gentle 
 heat hastens the complete separation of the precipitate. 
 
 The tersulphuret of arsenic is insoluble in cold hydrochloric 
 acid, and only very slightly soluble in the boiling concentrated 
 acid ; hot nitric acid decomposes and dissolves it to arsenic acid. 
 It is readily soluble, to a colorless solution, in the caustic alka- 
 lies, and in the alkaline sulphurets and carbonates. 
 
 When ten grains of a pure aqueous solution of arsenious 
 acid are placed in a small test-tube, acidulated with two drops 
 of hydrochloric acid, and treated with a slow stream of the 
 washed sulphuretted gas, the following results are obtained. 
 1. 100th solution, or xg- grain of arsenious acid, in ten grains^ 
 
 of water, yields a very copious, bright yellow precipitate, 
 
 which remains amorphous. 
 
264 ARSENIC. 
 
 2. 1,000th solution: an immediate precipitate, which very soon 
 
 becomes quite copious. 
 
 3. lOjOOOth solution : an immediate, yellow turbidity ; if the 
 
 mixture, after being saturated with the gas, be allowed to 
 stand at the ordinary temperature for several minutes, 
 quite good, yellow flakes appear, and these after a time 
 fall to a very good deposit. If the mixture be heated, 
 the precipitate separates almost immediately. 
 
 4. 25,000th solution : very soon, a yellow turbidity ; after stand- 
 
 ing about ten minutes, yellow flakes are just perceptible ; 
 and after a few hours, there is a quite satisfactory deposit. 
 If after the introduction of the gas, the mixture be heated, 
 the deposit appears within a very few minutes. 
 
 5. 50,000th solution : after a little time, a perceptible yellowish 
 
 turbidity ; in about an hotir, distinct flakes appear sus- 
 pended in the liquid, but their color is not satisfactory ; 
 after a few hours, they assume a distinct yellow hue, bixt 
 still remain suspended in the fluid, from which, however, 
 they almost immediately separate on the application of 
 heat. 
 
 6. 100,000th solution : after a few minutes, the mixture pre- 
 
 sents a perceptible cloudiness ; after several minutes, a 
 distinct turbidity and a just perceptible yellow tint ; after 
 a few hours, distinct flakes appear, but their true color is 
 not apparent ; after thirty-six hours, there is a quite dis- 
 tinct yellow deposit. One. hundred grains of the solution 
 yield in a little time, a very, perceptible yellowish turbid- 
 ity ; after a few hours, a decided yellow deposit ; in twenty- 
 four hours, the deposit is about the same as that from ten 
 grains of a 10,000th solution which has stood the same 
 length of time. 
 When normal solutions of the acid are treated with the 
 reagent, they also yield tersulphuret of arsenic ; but under 
 these conditions, the arsenical sulphuret, except when from con- 
 centrated solutions, entirely remains in solution, imparting a 
 jellow color to the liquid. Ten grains of a 100th solution of 
 this kind, yield after a little time, a quite good yellow precipi- 
 tate ; but the same quantity of a 1,000th solution yields only an 
 
SULPHURETTED HYDROGEN TEST. 265 
 
 intensely yellow liquid; a 25,000th solution yields a quite dis- 
 tinct yellow coloration ; and a 50,000th solution, after a little 
 time, acquires a perceptible yellow tint. Alkaline solutions of 
 the acid", even when highly concentrated, altogether fail to yield 
 a precipitate, when treated with the reagent. 
 
 The limit of the visible reaction of this test, when applied 
 to acidulated solutions of the poison, has been variously stated 
 by different observers. Thus, Lassaigne placed it, for solutions 
 acidulated with hydrochloric acid, at one part of arsenious acid 
 in 80,000 parts of liquid; Reinsch, at one part in 90,000; 
 Brandes, one part in 160,000; Devergie, one in 500,000; and 
 Horsley, at one part in 1,120,000 parts of fluid. Dr. Taylor 
 states, that the 400th part of a grain of the poison in half an 
 ounce of water, produced a scarcely perceptible yellow tint. In 
 this case, the acid was present in something less than 100,000 
 parts of liquid. 
 
 As neither of these observers, except Dr. Taylor, states 
 the quantity/ of solution operated upon, these discrepancies are 
 easily reconciled. The effect of quantity is well illustrated 
 under experiment 6, in which ten grains and one hundred 
 grains respectively of the same solution were employed. Here 
 it will be observed that although the degree of dilution was the 
 same, yet the absolute quantity of arsenic in one case was ten 
 times greater than in the other, and the results differed corre- 
 spondingly. It is obvious that a similar difference would be 
 observed between different quantities of any other solution, until 
 the degree of dilution equaled the solubihty of the tersulphuret 
 of arsenic, when no quantity, however great, would yield a 
 precipitate. 
 
 Confirmation of the Precipitate. — The arsenical nature of the 
 tersulphuret of arsenic may be established by either of the fol- 
 lowing methods : — 
 
 1. When the hydrochloric acid mixture containing the pre- 
 cipitate is boiled with a slip of bright copper-foil, the sulphuret 
 is decomposed with the deposition of metallic arsenic upon the 
 copper ; if the coated copper be then washed, dried, and heated . 
 in a reduction-tube, the metallic arsenic is volatilised and yields 
 a sublimate of octahedral crystals of arsenious acid. In this 
 
266 ARSENIC. 
 
 manner, the nature of the precipitate from less than the 1,000th 
 part of a grain of the poison may be fully established. 
 
 2. When tersulphuret of arsenic is dissolved in a few drops 
 of hot nitric acid, the solution cautiously evaporated to dryness, 
 and the dry residue treated with a few drops of a strong solu- 
 tion of nitrate of silver, it assumes a brick-red color, due to the 
 formation -of arsenate of silver. 
 
 3. When washed, dried, and heated in a reduction-tube, 
 tersulphuret of arsenic readily fuses to an orange-colored mass, 
 then entirely volatilises, yielding a sublimate, the lower portion 
 of which generally has an orange color and consists of micro- 
 scopic globules or drops ; the upper part of the sublimate has a 
 yellow color and its upper margin contains crystals of arsenious 
 acid. Small precipitates of the svilphuret are most readily 
 recovered, as recommended by Devergie, by collecting them 
 on a small filter, dissolving in ammonia, and evaporating the 
 solution at a gentle heat to dryness, in a watch-glass, when the 
 sulphuret remains as a yellow residue. 
 
 4. When the dried precipitate is mixed with several times 
 its volume of well-dried ferrocyanide of potassium, or of a 
 thoroughly dried mixture consisting of one part of cyanide of 
 potassium and three parts of carbonate of soda, and heated in 
 a reduction-tube, it undergoes decomposition with the produc- 
 tion of a sublimate of metallic arsenic. If this operation be 
 performed in a reduction-tube having a narrowly contracted 
 neck, the precipitate from the 1,000th part of a grain of arse- 
 nious acid, will yield very satisfactory results. 
 
 For the reduction of tersulphuret of arsenic by a mixture of 
 cyanide of potassium 'and carbonate of S'oda, Fresenius recom- 
 mends to heat the arsenical mixture in an atmosphere of dry 
 carbonic acid gas. For this purpose he employs the apparatus 
 illustrated in Fig. 8, next page. 
 
 The flask A is charged with a mixture of water and lumps 
 of solid marble, and sufficient hydrochloric acid added, through 
 the funnel-tube a, to evolve a moderate stream of gas; the car- 
 bonic acid thus evolved, is conducted by means of the tube 
 h into strong sulphuric acid contained in the flask B, where it 
 is thoroughly dried ; the tube c conducts the dried gas into the 
 
FALLACIES OF THE SULPHUR TEST. 
 
 267 
 
 reduction-tube C, in which is placed the arsenical mixture d. 
 When the apparatus is filled with the gas, the tube C is heated 
 in its whole length very gently until the contained mixture is 
 
 Fig. 8. 
 
 Freseniua' Apparatus for the reduction of Sulphuret of Arsenic. 
 
 quite dry ; when every trace of moisture is expelled, and the 
 stream of gas has become so slow that the single bubbles pass 
 through the sulphuric acid in B at intervals of about one second, 
 the reduction-tube is heated to redness at the point e, by means 
 of a spirit-lamp ; when e is red-hot, the flame of another lamp 
 is applied to the mixture, proceeding from h to e, until the whole 
 of the arsenic is expelled. The far greater portion of the vola- 
 tilised arsenic recondenses at /, .while a small portion escapes 
 through g, imparting to the surrounding air a peculiar garlic- 
 Kke odor. By slowly advancing the flame of the second lamp 
 up to /, the whole of the condensed arsenic collects in the nar- 
 row neck of the tube. The author of this process states that 
 it will yield a perfectly distinct metallic mirror from the 300th 
 part of a grain of tersulphuret of arsenic. (Qualitative Anal- 
 ysis, 1864, p. 142.) 
 
 Fallacies. — The only metal besides arsenic, with which sul- 
 phuretted hydrogen produces a bright yellow precipitate, is 
 cadmium. But, as the sulphuret of arsenic when precipitated 
 from organic solutions may have only a dull yellow color, it is 
 
268 - ARSENIC. 
 
 important to bear in mind that certain other sulphurets, either 
 in their pure state or when mixed with organic matter, may 
 also present a similar appearance. The only substances that 
 under any circumstance could thus be confounded with arsenic, 
 are cadmium, selenium, tin, and antimony. The sulphurets of 
 these substances possess the following properties : — 
 
 1. The sulphuret of cadmium is precipitated by the reagent 
 from moderately acid solutions of the salts of the metal, but 
 strongly acidulated solutions fail to yield a precipitate. The 
 precipitate is readily decomposed and dissolved by hydrochloric 
 acid ; so, also, unlike sulphuret of arsenic, it is insoluble in the 
 alkalies and their sulphurets, and it is, therefore, produced in 
 solutions containing a free alkali. When boiled with copper- 
 foil in water acidulated with hydrochloric acid, it fails to pro- 
 duce a deposit upon the copper. Fused in a reduction-tube 
 with a reducing agent, it yields a metallic subhmate, which, 
 however, in its physical appearance, is very unlike the arsen- 
 ical deposit, and which when resublimed in the open tube fails 
 to yield octahedral crystals. 
 
 2. Acidulated solutions of selenious acid, yield with sulphu- 
 retted hydrogen a precipitate of bisulphuret of selenium, which 
 at first has a yellow color, but soon changes to reddish-yellow, 
 and finally to orange-red. In dilute solutions, the precipitate 
 may remain suspended for some time, and present a yellow ap- 
 pearance, much like the arsenical compound; but after a time 
 it separates of its characteristic color. The same precipitate 
 separates from neutral and alkaline solutions. The precipitate, 
 like the arsenical sulphuret, is insoluble in hydrochloric acid, 
 even on the application of heat. Unlike the arsenical com- 
 pound, however, it is wholly insoluble in ammonia. It also fails 
 to yield a metallic deposit when boiled with diluted hydrochloric 
 acid and copper-foil. When fused with a reducing agent in a 
 reduction-tube, it yields a sublimate which may resemble some- 
 what that produced by arsenic, but the deposit fails to yield 
 octahedral crystals upon resublimation. 
 
 3. Per-combinations of tin yield with the reagent from acid- 
 ulated solutions, a precipitate of bisulphuret of tin, the color of 
 which in the moist state somewhat resembles that of sulphuret 
 
REINSCH'S TEST. 269 
 
 of arsenic, but when dried, it has a very dull yellow color. 
 The same precipitate separates from neutral, but not from alka- 
 line solutions. The precipitate is slowly soluble in cold hydro- 
 chloric acid, but readily in the hot concentrated acid. It is 
 very sparingly soluble in ammonia, but readily soluble in potash. 
 When boiled with water containing hydrochloric acid and a slip 
 of copper-foil, it may impart to the latter a slight stain, but 
 when the stained metal is heated in a reduction-tube, it fails to 
 yield a crystalline sublimate. The precipitate also fails to yield 
 a metallic sublimate when heated in a reduction-tube with a 
 reducing agent. 
 
 4. The sulphurets of antimony, as thrown down from pure 
 acidulated solutions, have an orange-red color ; the same pre- 
 cipitates are partially deposited in neutral and alkaline solutions 
 of the metal. The precipitates, unlike the sulphuret of arsenic, 
 are slowly soluble in cold concentrated hydrochloric acid, and 
 nearly wholly insoluble in ammonia; they are readily soluble in 
 caustic potash. When boiled with diluted hydrochloric acid 
 and copper-foil, they impart to the latter a metallic coating, 
 which usually has a violet color ; when the coated copper is 
 heated in a reduction-tube, it fails to yield octahedral crystals. 
 Nor wiU the precipitates when heated in a reduction-tube with 
 a reducing agent, yield a metallic sublimate. 
 
 4. Reinsclis Test. 
 
 When a solution of arsenious acid or of an arsenite is 
 strongly acidulated with hydrochloric acid, and the mixture 
 boiled with bright metallic copper, the latter decomposes the 
 arsenical compound and receives a coating of metallic arsenic. 
 This fact was first observed, in 1843, by Reinsch ; but Dr. 
 Taylor was the first to apply it as a test in medico-legal inves- 
 tigations. The proportion of hydrochloric acid employed, should 
 form about one-eighth of the volume of the arsenical solution ; 
 without the addition of the acid, the metal is not deposited. 
 The copper may be employed either in the form of fine wire 
 or of very thin foil ; the latter, however, is preferable. It is 
 essential that the copper have a bright surface : this is readily 
 
270 ARSENIC. 
 
 effected by means of a fine file or of sand-paper. The color of 
 the metallic deposit will depend much upon the thickness of the 
 latter : when quite thin, it presents a bluish or violet appear- 
 ance, but when comparatively thick, it has a steel-like or iron- 
 grey color. When the metallic coating is very thick, continued 
 boiling causes it to separate from the copper, in the form of 
 greyish or black scales. 
 
 This deposit is not, as was formerly supposed, pure metallic 
 arsenic, but a combination of this metal and copper. M. Lip- 
 pert, from recent researches, maintains that it has a constant 
 composition, being a definite alloy, consisting of 32 per cent, of 
 arsenic and 68 per cent, of copper, its formula being CujAs. 
 The large proportion of copper contained by the deposit, adds 
 very much to the delicacy of the test. This reaction will serve 
 to withdraw the whole of the arsenic from solutions of arse- 
 nious acid and of arsenites ; but when the metal exists in the 
 form of arsenic acid, it is deposited only from somewhat strong 
 solutions. 
 
 The arsenical nature of the deposit may be shown in the 
 following manner : the coated copper, after being carefully 
 washed with pure water and dried in a water-bath, is heated 
 by means of a spirit-lamp in a narrow, perfectly dry and clean 
 reduction-tube, when the arsenic volatilises, and becoming oxid- 
 ised yields a sublimate of octahedral crystals of arsenious acid. 
 This sublimate usually forms within from a quarter to half an 
 inch above the point at which the heat is applied. When the 
 sublimate is not exceedingly minute, it presents a well-defined 
 ring of sparkling crystals to the naked eye. Under the micro- 
 scope, these crystals present the appearances illustrated in Plate 
 IV, fig. 5. The absolute size of the crystals will depend some- 
 what upon the quantity of the metal present, as well as upon 
 the diameter of the reduction- tube. The portion of the tube 
 containing the sublimate may be separated with a file, boiled in 
 a very small quantity of water, and the solution examined by 
 the ammonio-nitrate of silver or any of the other tests for arse- 
 nious acid. 
 
 When one grain of a pure aqueous solution of arsenious acid 
 is acidulated with pure hydrochloric acid, and the mixture 
 
REINSCH'S TEST. 271 
 
 heated in a thin watch-glass with a small fragment of bright 
 
 copper-foil, it yields the following results. 
 
 !• Too' grain of arsenious acid, yields a copious, iron-grey de- 
 posit, which when heated in a narrow reduction-tube fur- 
 nishes a very good sublimate, consisting of innumerable 
 octahedral crystals. 
 
 2. TTFoij grain, yields a good, steel-like deposit, which M'hen 
 
 sublimed in a reduction-tube yields results similar to 1, 
 only that the crystals are generally somewhat smaller. 
 
 3. j-oToiJTJ grain : as soon as the mixture is heated to the boiling- 
 
 temperature, the copper shows a distinct deposit, which in 
 a little time becomes quite satisfactory ; when this is vola- 
 tilised in a very narrow reduction-tube, it yields a subli- 
 mate visible to the naked eye, and which under the 
 microscope is very satisfactory. 
 When deposits smaller than the one just mentioned are 
 heated in a reduction-tube of the ordinary form, even of very 
 narrow bore, the results are not uniform, due to the fact that 
 the sublimate is distributed over a comparatively large space, 
 and part of it seems to entirely escape condensation, at least in 
 the lower portion of the tube. With such deposits, however, 
 very uniform results may be obtained by the following method. 
 A thin, perfectly clean and dry tube, of about xo inch in diam- 
 eter, is drawn out into a capillary neck having an internal bore 
 of about the 40th part of an inch, as illustrated in Fig. 9, A. 
 The coated copper is then in- 
 troduced through the wider 
 portion of the tube to the 
 point c, and the neck of the 
 tube at a little distance above 
 the copper moistened with 
 water or wrapped with wet 
 cotton. The wide end of the 
 tube is then cautiously fused shut by a very small blow-pipe 
 flame, and the fusion slowly advanced to the point occupied by 
 the copper, as shown in B. The capillary end may now be 
 fused shut. When wiped and examined by the microscope, the 
 arsenical sublimate will be found at about the point m, forming 
 
 Fig. 9. 
 
 A 
 
 B 
 
 Tubes for Sublimation of Arsenic. Natural size 
 
272 ARSENIC. 
 
 a very narrow ring of octahedral crystals. As these tubes may 
 readily be formed with walls less than the 100th part of an 
 inch in thickness, they permit the application of the higher 
 powers of the microscope. They may be reserved for future 
 examination; after a time, however, the sublimate deteriorates 
 somewhat, and may even, if the deposit is very small, wholly 
 disappear. 
 
 4. 2"57oiro grain : when a fragment of copper-foil measuring 
 about tV by 2V inch is employed, and the mixture kept 
 at a boiling heat for some time, with renewal of the evap- 
 orated fluid by pure water, the copper acquires a decided 
 steel-like coating ; when this is sublimed in a tube of the 
 form described above, it yields to the naked eye a visible 
 mist, which under an amplification of seventy-five diam- 
 eters is found to consist of many hundreds of weU-defined 
 octahedral crystals. In a number of instances, over one 
 hundred crystals, varying in size from the 2,000th to the 
 8,000th of an inch in diameter, were counted in a single 
 field of a 2-3ds inch objective, without change of focus ; 
 most of the crystals measured about the 4,000th of an 
 inch in diameter, 
 o- 5 0,0 grain, when treated for some minutes as under 4, im- 
 parts to the copper a distinct steel-like tarnish, which 
 when volatilised, in the manner described above, yields 
 a very satisfactory microscopic sublimate. In many in- 
 stances, over fifty crystals, measuring from the 3,000th to 
 the 10,000th part of an inch in diameter, were counted in 
 a single field of the objective. So far as the evidence of 
 the presence of octahedral crystals is concerned, this sub- 
 limate, under the microscope, is as satisfactory as that 
 from the 100th part of a grain or larger quantity of the 
 poison, the only difference being in the size and number 
 of the crystals. 
 6. To"o7oo"o gi'ain : the copper receives a very slight tarnish, 
 which when volatilised sometimes yields a satisfactory 
 crystalline subKmate ; but frequently the crystals are so 
 minute that their angular nature can not be satisfactorily 
 determined. 
 
FALLACIES OF REINSCH'S TEST. 273 
 
 For the examination of these sublimates, a magnifying power 
 of about seventy-five diameters is generally the most useful. 
 Under this amplification, the angular nature of a crystal meas- 
 uring the 5,000th of an inch in diameter, is perfectly distinct 
 and satisfactory : the weight of such a crystal would not exceed 
 the 200,000,000th part of a grain. Under the same power, a 
 crystal measuring the 10,000th of an inch, appears only as a 
 distinct point ; but with a power of one hundred and fifty, its 
 angular form may be distinctly recognized : its weight would 
 be less than the 1,000,000,000th of a grain. On account of 
 the curvature of the glass tube, crystals but little less in size 
 than the last-mentioned, are not easily determined, even with 
 the higher powers of the microscope. It is not, of course, 
 intended to imply that quantities of the poison in themselves as 
 small as those just mentioned could be recovered from a solution 
 and reproduced in the crystalline form ; but only that these 
 crystals may thus be recognised and identified when they form 
 separate portions of a sublimate. The least quantity of the 
 poison that will furnish these crystals, even with the greatest > 
 care and under the most favorable circumstances, according to 
 the above method, is about the 50,000th part of a grain. 
 
 Various and very discordant limits have been assigned to 
 this test, by difi'erent observers. However, as these experi- 
 mentalists only state the degree of dilution, without mentioning 
 either the quantity of solution examined, the size of the copper 
 or the diameter of the reduction-tube employed, these discrep- 
 ancies are readily explained. 
 
 Fallacies. — The production of a sublimate of octahedral crys- 
 tals by this test, is perfectly characteristic of arsenic. Various 
 other metals, however, as antimony, mercury, silver, bismuth, 
 platinum, palladium, and gold, are deposited upon copper under 
 the same conditions as arsenic. Tin may also impart a slight 
 stain to the copper ; so, also, organic matter, especially if it 
 contain sulphur ; and the prolonged action of boiling hydro- 
 chloric acid alone may produce a distinct tarnish. The antimo- 
 nial deposit has usually a peculiar, violet color, while the deposits 
 from mercury, silver, and bismuth have generally a bright sil- 
 very appearance, and that from gold a yellow hue. Under 
 
 18 
 
274 ARSENIC. 
 
 certain circumstances, however, most of these deposits may 
 closely resemble that from arsenic. The platinum and palladium 
 deposits present an appearance very similar to that of the 
 arsenical coating. 
 
 Of these various metallic deposits, the only ones which when 
 heated in a reduction-tube, will, like arsenic, volatilise and yield 
 a sublimate, are mercury and antimony. But, the sublimate 
 from mercury consists of opake spherical globules, which when 
 viewed under incident light with the microscope, have a bright 
 silvery appearance ; and that from antimony, is amorphous or 
 at most granular : both these sublimates, unlike that from ar- 
 senic, are insoluble in water. Moreover, the antimonial subli- 
 mate is only obtained from comparatively thick crusts of the 
 metal, and deposits in the reduction-tube much nearer the cop- 
 per than that from arsenic; it also requires a higher heat for 
 its formation. In this connection it should be remembered, that 
 commercial tartar emetic sometimes contains sufficient arsenic, 
 as an impurity, to yield in this manner a very distinct subli- 
 mate of octahedral crystals, in advance of the antimonial deposit. 
 
 A deposit of organic matter upon the copper, may also give 
 rise to a sublimate, but this is amorphous, and its true nature 
 is at once revealed by the microscope. When very complex 
 organic mixtures strongly acidulated with hydrochloric acid, are 
 boiled for some time in contact with metallic copper, the metal 
 may present a very distinct stain, and yield an amorphous sub- 
 limate which sometimes contains small acicular crystals, con- 
 sisting apparently of a compound of copper. This sublimate 
 deposits very near the copper, and is not resublimed upon the 
 further application of heat. Finally, if the copper-foil or the 
 reduction-tube is not perfectly dry, the moisture may condense 
 in the form of a mist-like deposit at about the point at which 
 the arsenical sublimate usually forms ; but the true nature of 
 this deposit also is at once revealed by the microscope. 
 
 From what has now been stated, it is obvious that the presT 
 ence of arsenic is not fully established until the coated copper 
 yields a sublimate of octahedral crystals. In applying this 
 confirmatory reaction, however, it should be borne in mind, that 
 when a comparatively large arsenical deposit is heated in a very 
 
FALLACIES OF REINSCH'S TEST. 275 
 
 small reduction-tube, the sublimate may consist alone of gran- 
 ules, or a portion of the arsenic may even deposit in its metallic 
 state. It rarely happens, however, that at least the upper 
 margin of an arsenical sublimate does not contain the charac- 
 teristic crystals. Should there be any doubt as to the nature 
 of the sublimate, the lower end of the tube may be removed, 
 and the deposit resublimed, when, if consisting of arsenic, it 
 will be converted into the crystalline form. In all cases, the 
 size of the reduction-tube should be in suitable proportion to 
 the quantity of deposit to be examined. 
 
 But even should this test, when applied to a suspected solu- 
 tion, yield an arsenical sublimate, it, of course, would not follow 
 that the poison was reaUy derived from the suspected liquid, 
 unless the analyst was perfectly certain of the purity of the 
 hydrochloric acid, and in some instances also of the copper, 
 employed. As found in commerce, hydrochloric acid not un- 
 frequently contains very notable quantities of arsenic. In all 
 cases, a portion of the sample of the acid about to be employed, 
 should first be diluted with five or six volumes of water and 
 boiled for about ten minutes with a slip of bright copper ; if 
 this fails to yield a deposit, the acid may be considered free 
 from arsenic. In regard to the purity of copper, it is now 
 known, chiefly through the recent researches of Dr. Taylor, 
 that this metal as usually employed in investigations of this 
 kind, nearly always contains traces of arsenic. This impurity, 
 however, could only lead to error when the copper is acted 
 upon and dissolved by the liquid with which it is boiled ; any 
 arsenic thus dissolved might then deposit upon a fresh portion 
 of the copper. This objection, therefore, has no practical force, 
 except in cases in which a very notable quantity of the copper 
 has dissolved, and only a very minute trace of arsenic has been 
 detected. When, in the application of the test to a suspected 
 solution, the copper promptly receives an arsenical deposit, 
 which after the addition of successive slips of the metal ceases 
 to take place, it is quite certain that the poison is not derived 
 from the copper. 
 
 For the detection of traces of arsenic in copper, we have 
 found the following method, first advised by F. Field (Chem. 
 
276 ARSENIC. 
 
 Gaz., 1857, p. 313), exceedingly delicate. Ten grains of tlie 
 copper are dissolved in slight excess of pure, hot, nitric acid, 
 the solution diluted to about three ounces of fluid, and ammonia 
 added until the oxide of copper is precipitated, but not redis- 
 solved; the precipitate is then redissolved by the addition of 
 about twenty-five grains of oxalate of ammonia, the oxalate of 
 copper thus produced precipitated by slight excess of hydro- 
 chloric acid, and the mixture allowed to stand some hours. The 
 solution is then filtered, the filtrate saturated with sulphurous 
 acid gas, concentrated to a small volume, and tested for arsenic, 
 either by sulphuretted hydrogen 6r by a fresh piece of copper. 
 
 For this same purpose, Dr. Odling recommends (Jour. Chem. 
 Society, July, 1863, p. 248) to distiU a few grains of the cop- 
 per, cut into small pieces, with an excess of pure hydrochloric 
 acid and perchloride of iron, the distillation being carried to 
 dryness : the dry residue may be redistilled with a little fresh 
 hydrochloi'ic acid. By this treatment, the copper is quickly 
 dissolved, and any arsenic present converted into chloride and 
 thus carried over with the distillate. The distillate is tested for 
 arsenic in the usual manner. Perchloride of iron, Dr. Odling 
 adds, may be purified from arsenic, by evaporating it once or 
 twice to dryness with excess of hydrochloric acid. 
 
 Interferences. — Should this test fail to yield a metallic de- 
 posit upon the copper, it would not follow, from this fact alone, 
 that arsenic was entirely absent, since the deposition of this 
 metal may be prevented by the presence of certain other sub- 
 stances. Thus in even strong solutions of the poison containing 
 only a small quantity of a chlorate, as chlorate of potash, the 
 copper remains perfectly bright ; but the liquid acquires a bluish 
 or greenish-blue color, due to the formation of a soluble salt of 
 copper. Should arsenic and a chlorate occur- in the same mix- 
 ture, the solution is cautiously evaporated to dryness, and the dry 
 residue fused in a long, narrow, glass tube, until the evolution 
 of oxygen ceases : by this operation, the chlorate will be con- 
 verted into a chloride, and the arsenic into arsenic acid. The 
 tube is then cut into small pieces and boiled with a small quan- 
 tity of pure water, until the saline matter has entirely dissolved, 
 and the solution thus obtained, after filtration if necessary. 
 
ADVANTAGES OF REINSCH'S TEST. 277 
 
 saturated with sulphurous acid gas, the excess of which is after- 
 wards expelled by a gentle heat. The solution, which now con- 
 tains the arsenic as arsenious acid, together f^ith the chloride 
 resulting from the decomposition of the chlorate, may be acidu- 
 lated with hydrochloric acid and examined in the usual manner. 
 So also, the presence of binoxide of manganese, and of other 
 substances that decompose hydrochloric acid with the elimina- 
 tion of free chlorine, may interfere with the reaction of the test. 
 And the same is true of free nitric acid. This acid, however, 
 has little action upon the test unless present in quite notable 
 quantity or the solution be concentrated to a small volume, when 
 it acts upon and dissolves the copper. In case of the presence 
 of free nitric acid, the solution may be neutralised with caustic 
 potash, then acidulated with hydrochloric acid, and tested as 
 usual ; or, the solution may be cautiously evaporated to dryness, 
 the residue dissolved in water, this solution saturated with sul- 
 phurous acid gas, then gently heated to expel the excess of gas, 
 and examined. 
 
 The alkahne nitrates have little or no effect upon the test 
 until the solution is evaporated to near dryness, when they 
 cause the solution of the copper. In a mixture containing the 
 5th of its weight of nitrate of potash and the 500th part of 
 arsenious acid, the reaction takes place much the same as in a 
 pure solution of the poison. 
 
 In conclusion, it may be remarked that this method of 
 Reinsch possesses several advantages which entitle it to more 
 consideration than it has usually received at the hands of chem- 
 ists. Thus, it is easily and quickly applied, requiring but little 
 apparatus, and that of the most simple kind ; it usually requires 
 the purity of only one substance, namely, the hydrochloric acid, 
 to be known, and this is readily established by means of the 
 test itself; it requires no dilution of the suspected liquid, but 
 on the contrary permits its concentration to almost any extent 
 while the test is being applied ; it may be applied directly to 
 much more complex organic mixtures than either of the other 
 tests for this poison ; and finally, it serves to separate from com- 
 plex mixtures and reproduce in an imequivocal form, a less 
 quantity of the poison than any other known test, excepting 
 
278 ARSENIC. 
 
 perhaps, one of the methods of Marsh's process, with which, 
 however, it is equally delicate. 
 
 5. Marsh's Test. 
 
 When a mixture of zinc and water is treated with sulphuric 
 acid, the zinc is oxidised at the expense of the oxygen of the 
 water, while the hydrogen of the latter passes off in its free 
 state : Zn + HO + SO3 = ZnO, SO3 + H. If, however, arsenious 
 acid, arsenic acid or any of the soluble compounds of the metal 
 be present in such mixture, the zinc is partially oxidised at the 
 expense of the oxygen of the arsenical compound, and the whole 
 of the arsenic thus eliminated unites with part of the nascent 
 hydrogen, forming arseniiretted hydrogen gas (AsHg). The re- 
 action in the case of arsenious acid, is as follows : 3 HO + AsOj + 
 ff Zn + 6 SO3 = 6 ZnO, SO3 + AsHg ; with arsenic acid : 3 HO + 
 AsOs + 8 Zn + 8 SO3 = 8 ZnO, SO3 + AsHj. When the arsenic is 
 present as a chloride, it yields hydrochloric acid and the arsen- 
 uretted gas. Neither metallic arsenic nor the sulphurets of the 
 metal, will yield a trace of the gas. The production of arsen- 
 uretted hydrogen, under these conditions, has long been known, 
 but Mr. Marsh, of Woolwich, in 1836, was the first to employ 
 it as a method for the detection of arsenic. 
 
 Arsenuretted hydrogen is a colorless, extremely poisonous 
 gas, having a peculiar alliaceous odor, and specific gravity of 
 2'695 ; it is neutral in its reaction, and but sparingly soluble in 
 water. It bums with a bluish flame, giving rise to arsenious 
 acid, and is readily decomposed by heat, into free hydrogen and 
 metallic arsenic; it is also readily decomposed by solutions of 
 the easily reducible metallic oxides. These properties serve, in 
 the manner to be pointed out hereafter, for the detection of very 
 minute traces of the gas. 
 
 Various forms of apparatus have been proposed for the pro- 
 duction of this gas in its application to the detection of arsenic, 
 but the most efiicient is that advised by Otto, as illustrated, in 
 principle, by Fig. 10, next page. The gas-flask A, which may 
 be substituted by a simple wide-mouthed bottle or in delicate 
 experiments by a long test-tube, is provided with a closely 
 
MARSH'S TEST. 
 
 279 
 
 fitting cork carrying the funnel-tube a, and the exit-tube i ; 
 this tube should be tolerably wide, and have its lower end cut 
 obliquely, to facilitate the dropping back of any condensed 
 liquid into the flask, c is a drying-tube containing fragments 
 
 Apparatus for the Application of Marsh's Test. 
 
 of hydrate of potash or of chloride of .calcium, kept in their 
 place by loose cotton. Unless the experiment is to be con- 
 tinued for some time, it is only necessary to loosely fill the 
 drying-tube with cotton moistened with concentrated sulphuric 
 acid. This tube is connected with the tube 6, by means of a 
 perforated cork, and with the reduction-tube d, by a short india- 
 rubber tube. The reduction-tube {d) should be of- hard glass, 
 free from lead, and have an internal diameter of about 3-20ths 
 of an inch, and walls not less than the 20th of an inch in thick- 
 ness ; its outer portion should be contracted in two or three 
 places, as shown in the figure, and terminate in a turned-up, 
 drawn-out point, which is fused in a small flame of a spirit-lamp. 
 
280 ARSENIC. 
 
 until the opening becomes quite small. By preparing the end 
 of the tube in this manner, there is no danger of its fusing 
 shut, when the jet of gas is afterwards ignited. In very deli- 
 cate experiments, the bore of the contracted portions of the 
 tube should not exceed the 20th of an inch in diameter. Sev- 
 eral of these tubes should be prepared and at hand. 
 
 About two ounces of pure zinc, either granulated or cut into 
 small pieces, are now placed in the flask A, and, the apparatus 
 being adjusted, covered with a cooled mixture consisting of one 
 measure of pure concentrated sulphuric acid and four measures 
 of distilled water, added through the funnel-tube a, which 
 should extend to near the bottom of the flask. The zinc wiU 
 now immediately begin to decompose the water with the evolu- 
 tion of hydrogen, in the manner before described. Should, 
 however, the zinc or the sulphuric acid be contaminated with 
 arsenic, as not unfrequently is the case, it will give rise to 
 arseniiretted hydrogen. Before, therefore, applying the test to 
 a suspected solution, the purity of the materials employed must 
 be fuUy estabKshed. For this purpose, after the apparatus has 
 become completely filled with hydrogen and while the gas is 
 still being evolved, the outer uncontracted portion of the reduc- 
 tion-tube is heated to redness, as illustrated in the figure, for 
 about fifteen minutes. If this fails to produce a metallic de- 
 posit or stain in the contracted part of the tube, in advance of 
 the part heated, the material may be considered free from 
 arsenic. The purity of the materials having been thus estab- 
 lished, it may be necessary to wash and renew the zinc, dry 
 the tubes, and add a fresh portion of the diluted acid. 
 
 The apparatus being adjusted and completely filled with 
 evolved hydrogen, the jet of gas, as it issues from the drawn- 
 out end of the -reduction-tube, is ignited, care being taken not 
 to apply a light until the whole of the atmospheric air is ex- 
 pelled from- the apparatus, as otherwise an explosion might 
 occur. A small quantity of the arsenical solution is then intro- 
 duced into the funnel-tube, and washed into the flask by the 
 subsequent addition of a few drops of the diluted sulphuric acid. 
 The decomposition of the arsenical compound, with the evolution 
 of arsenuretted hydrogen, will commence immediately. The 
 
MARSH'S TEST. 281 
 
 presence of the arsenuretted gas may be established by three 
 different methods, namely : a. By the propei^ties of the ignited 
 jet ; /?. By decomposing it by heat applied to the reduction-tube; 
 and y. By its action upon a solution of nitrate of silver. 
 
 a. The ignited jet. — As soon as the arsenical solution is 
 introduced into the flask, the evolution of gas increases; this 
 increase is quite perceptible, even when the liquid within the 
 flask contains only the 1,000,000th part of its weight of arse- 
 nious acid. The flame of the ignited jet will now increase in 
 size, acquire a bluish tint, and, unless only a minute quantity 
 of arsenic is present, evolve white fumes of arsenious acid; so 
 also, sometimes, the flame emits a peculiar alliaceous odor. If 
 the white fumes thus evolved be received upon a cold surface, 
 as an inverted watch-glass, they condense to a white powder, 
 which sometimes contains octahedral crystals. The arsenical 
 nature of this powder may be shown by any of the methods 
 heretofore pointed out for the recognition of solid arsenious 
 acid. This, however, is by no means a delicate method for 
 detecting the presence of the arsenuretted gas; and it should 
 never be employed to the exclusion of that now to be mentioned. 
 
 If the flame be allowed to strike against a cold body, as a 
 piece of white porcelain held in a horizontal position, it yields 
 a deposit of metallic arsenic on the cold surface. In experi- 
 ments with very dilute solutions, the porcelain should be applied 
 immediately after the introduction of the arsenical compound, 
 since the evolution of the arsenuretted gas begins at once, and 
 the whole of the metal may be thus rapidly evolved. As soon 
 as a well-marked deposit is obtained on the porcelain, the posi- 
 tion of the latter should be changed, so that the flame may 
 strike upon a fresh surface; if it can be done, a number of 
 these deposits should be collected upon several dififerent pieces 
 of the porcelain. 
 
 When the amount of arsenic present is not very minute, 
 the central portion of the deposits thus obtained presents a 
 bright steel-like appearance; this is surrounded by a darker 
 and less lustrous portion, the outer margin of which has some- 
 times a brownish color. The exact appearance of these deposits, 
 however, depends much upon the quantity of arsenic present, 
 
282 ARSENIC. 
 
 the character of the flame, and the position occupied by the 
 porcelain: sometimes they consist simply of brownish stains, 
 whilst at others, they are in the form of rings. From very 
 dilute solutions, they are produced only when the gas burns 
 with a. small, steady, round flame; when the supply of gas is 
 so rapid as to produce a long pointed flame, they are sometimes 
 not obtained from even strong solutions of the metal. When 
 the gas burns with a conical flame, the porcelain should be 
 applied at about the center of its upper third or stiU nearer 
 its point; on the other hand, when the flame is short, full, and 
 round, the cold surface should be held very near its base. 
 
 Delicacy of this method. — In investigating the limit of this 
 test, in regard to the pi'oduction of metallic deposits on cold 
 porcelain, a gas-flask of about three fluid ounces capacity was 
 employed, except when the entire quantity of fluid did not 
 exceed one hundred grain-measures, when the flask was sub- 
 stituted by a test-tube, three-fourths of an inch in diameter 
 and five inches long. For the examination of very minute 
 quantities of arsenious acid, or of any other soluble combina- 
 tion of the metal, a test-tube has an advantage over a flask, in 
 that the arsenical solution can, by means of the funnel-tube, be 
 brought in contact with the zinc and be thus decomposed be- 
 fore becoming much diffused through the diluted sulphuric acid. 
 1- TTTo'o grain of arsenious acid, in solution in ten grains of 
 water, when added to an active apparatus containing some- 
 thing less than an ounce of pure zinc and exactly ninety 
 grain-measures of diluted sulphuric acid, yields in a few 
 moments, from the ignited jet, metallic deposits, which 
 continue to be formed, until about sixty can be obtained, 
 after which the evolved gas gives no evidence whatever 
 of the presence of the metal. The degree of dilution in 
 this case, providing the poison became equally diffused 
 throughout the whole of the liquid in the apparatus, would 
 be one part of arsenious acid in 100,000 parts of the 
 liquid mixture. 
 Of six experiments, in each of which the 1,000th part of 
 a grain of arsenious acid, in solution in ten grains of water, 
 was added to an active apparatus containing two hundred and 
 
MARSH'S TEST. 283 
 
 ninety grain-measures of diluted sulphuric acid — the poison now 
 forming only the 300,000th part of the liquid mixture — the 
 highest number of well-defined deposits obtained was sixty- 
 seven, the lowest fifty-two. If, therefore, none of the metallic 
 arsenic escaped condensation — which however is not the fact — 
 a single deposit could not on an average have represented more 
 than the 60,000th part of a grain of arsenious acid, or only 
 about the 80,000th of a grain of the metal; yet they each, 
 with very few exceptions, measured from the 10th to the 14th 
 of an inch in diameter. The size of these deposits, will of 
 course depend some^vhat upon the size of the flame, which in 
 its turn will depend upon the supply of gas and the orifice of 
 the tube. 
 
 Experiments made with the same quantity of the poison in 
 the presence oi five hundred grains of liquid — or under a dilu- 
 tion of 500,000 parts of fluid — gave much the same results as 
 those just described. 
 
 2- 2.500 grain of arsenious acid, in an apparatus containing 
 one hundred grains of liquid — or under a dilution of 250,- 
 000 — furnished as the average of six experiments, twenty- 
 nine very satisfactory deposits. 
 The same quantity of the poison in five hundred grains of 
 liquid, or under a dilution of 1,250,000, gave, in several experi- 
 ments, several distinct stains, but in no instance were the results 
 satisfactory. 
 
 3. jTooT) grain of arsenious acid, in one hundred grains of fluid, 
 or under a dilution of 500,000, usually yields several sat- 
 isfactory deposits. But the same quantity of the poison 
 in three hundred grains of liquid, failed in several instances 
 to yield any satisfactory evidence of its presence. 
 The limit of this test, as applied in this manner, has been 
 variously assigned; but with few exceptions, the experimenters 
 have only stated the degree of dilution of the solution, without 
 mentioning the quantity employed. Thus it has been stated 
 that the method will yield satisfactory deposits when the solu- 
 tion contains only the 2,000,000th part of its weight of arsenic. 
 This is true, but it requires about one thousand grains of such 
 a solution to furnish these results; the absolute quantity of the 
 
284 ARSENIC. 
 
 poison present would therefore be about the 2,000th part of a 
 grain. These statements have generally led to a misappre- 
 hension of the real delicacy of this test; and it has, therefore, 
 in this respect been much overestimated. It is a fact, that 
 this method of Marsh, when referred to the mixture within the 
 apparatus, will indicate the presence of the poison under a 
 greater degree of dilution than any other known test; but at 
 the same time, it requires a much larger quantity of the solution 
 for its application than will serve for either of the other tests. 
 
 From the experiments already cited, it would appear that 
 when one hundred grains of liquid are employed — and this is 
 about the smallest quantity that will evolve sufficient gas for 
 the purpose — the least quantity of arsenious acid that will 
 yield satisfactory deposits, is about the 5,000th part of a grain. 
 This, therefore, so far as the production of deposits is con- 
 cerned, is about the limit of the test. It has generally been 
 conceded that this method would reveal the presence of a 
 smaller quantity of arsenic than could be recovered by the 
 method of Reinsch; but this is not the fact, since the latter 
 process, in the manner already described, will serve to detect 
 a much less quantity of the poison than can be made to reveal 
 any evidence of its presence by at least this part of the method 
 of Marsh. 
 
 Fallacies. — Solutions of antimony, under these same 'condi- 
 tions, undergo decomposition with the production of antimonu- 
 retted hydrogen gas, which, like arsenuretted hydrogen, burns 
 with the evolution of white fumes, and yields metallic deposits 
 upon cold surfaces applied to the flame. It, however, unlike, 
 the arsenuretted gas, is destitute of odor, and burns with a 
 greenish flame; moreover, when the white fumes evolved are 
 condensed on a cold body, they yield an amorphous deposit, 
 which is insoluble in water, and immediately assumes an orange- 
 red color when moistened with a solution of sulphuret of am- 
 monium; whilst that obtained from arsenic, under similar cir- 
 cumstances, is soluble in water, and undergoes no immediate 
 change when treated with sulphuret of ammonium. 
 
 The metallic deposits produced by antimonuretted hydrogen 
 upon a piece of cold porcelain, are usually destitute of luster, 
 
FALLACIES OF MARSH'S TEST. 285 
 
 and have a much darker color than those obtained from arsenic. 
 These characters readily serve to distinguish between compara- 
 tively thick crusts of these metals; but in very thin deposits, 
 they may be entirely lost. The deposits of the two metals, 
 however, differ greatly in regard to their chemical properties. 
 1. The arsenical crusts, except when very thin, are only very 
 slowly soluble in a drop or two of a yellow solution of sulphuret 
 of ammonium; whilst the antimonial deposits are readily soluble 
 in this reagent. When the ammoniacal solution is evaporated 
 to dryness on a water-bath, the arsenic remains as a bright 
 yelloiv deposit of tersulphuret of arsenic, which is readily solu- 
 ble in ammonia, but insoluble in hydrochloric acid; under the 
 same conditions, antimony yields an orange-red residue, of ter- 
 sulphuret of antimony, which is insoluble in ammonia, but 
 readily soluble in concentrated hydrochloric acid. This method 
 will serve for the discrimination of very minute deposits of the 
 metals. 2. The spots produced by arsenic, are readily soluble 
 in a solution of hypochlorite of soda or of lime; whereas those 
 from antimony, are insoluble or only dissolve after prolonged 
 digestion, in a solution of this kind. 3. The deposits from 
 both metals readily dissolve in a drop of warm nitric acid, and 
 yield on the cautious evaporation of the liquid, a white residue. 
 When, however, the arsenical residue is touched with a drop 
 of a solution of nitrate of silver, it assumes a brick-red color; 
 whilst that from antimony remains unchanged. Various other 
 methods have been proposed for distinguishing between these 
 stains, but in point of delicacy they are much inferior to those 
 already described. 
 
 Besides this fallacy of antimony, it has been objected that 
 organic matter, certain combinations of iron, phosphorus, and 
 sulphur, may under the above conditions yield stains somewhat 
 similar to those produced by arsenic. But neither of these 
 substances will yield a succession of spots ; nor will either of 
 them yield a single stain having the properties described under 
 either of the three methods just mentioned for the identification 
 of the arsenical deposit. In experiments for the purpose with 
 mixtures containing iron, phosphorus, and sulphur, we have 
 failed to obtain any stain whatever having the most remote 
 
286 ARSENIC. 
 
 resemblance to that produced by arsenic ; nor, in numerous ap- 
 plications of the test to animal and vegetable mixtures, have 
 we ever found it yield an organic stain. 
 
 /?. Decomposition of the gas by heat. — As originally pro- 
 posed by Marsh, this test consisted simply in obtaining metallic 
 deposits from the ignited jet of gas, as now described. Berze- 
 lius was, perhaps, the first to resort to the decomposition of the 
 arsenuretted gas by heat, as a means of its detection. The 
 apparatus being filled with hydrogen and the evolution of gas 
 quite moderate, a large flame of a common spirit-lamp, which 
 we prefer to an argand-burner, is applied to the reduction-tube, 
 at a point about half or three-quarters of an inch on the inside 
 of the outer contraction. When the part of the tube to which 
 the flame is applied is quite red hot, a very small quantity of 
 the arsenical solution is introduced, by means of the funnel-tube, 
 into the flask. The arsenuretted hydrogen now evolved, as it 
 passes through the red-hot portion of the reduction-tube, will 
 be decomposed with the production of a deposit of metallic 
 arsenic in the contracted part, in advance of the flame. After 
 a good deposit has thus formed, the heat of the lamp may be 
 so changed that the metal may be deposited in the second con- 
 tracted portion of the tube. 
 
 The physical appearance of the deposits thus obtained, de- 
 pends somewhat upon the quantity of arsenic present, but they 
 usually, especiaUy when obtained from very dilute solutions, 
 consist of three conjoined portions, the inner of which is trans- 
 parent and of a brown color, while the central part has a brill- 
 iant metallic appearance, and this fades into a lighter colored 
 or grey portion, which is imperceptibly lost. Very thick de- 
 posits may present much the same characters as presented by 
 the sublimed metal, already described. When the quantity of 
 arsenic present is comparatively large and the current of gas 
 rapid, sometimes arsenical stains may be obtained from the 
 ignited jet at the same time that a deposit is being formed in 
 the heated tube. 
 
 Delicacy of (his method. — A much smaller quantity of the 
 metal will yield deposits by this process than will serve for its 
 detection from the ignited arsenuretted gas. This difierence is 
 
MARSH'S TEST. 287 
 
 due to the fact that by the method under consideration, the 
 metal eliminated from the decomposed gas may be collected at 
 about the same point for several minutes or longer if necessary ; 
 whereas from the gas when ignited, it can be collected at the 
 same place for only a few moments. Another advantage of this 
 method over the preceding is, that it may be applied with a less 
 quantity of liquid, since it requires only a feeble current of gas. 
 In the following experiments, one hundred grain-measures 
 of liquid, including the arsenical solution, were present in the 
 apparatus, and the reduction-tube was contracted to a bore of 
 about the 20th of an inch in diameter. The arsenious acid, as 
 introduced in the apparatus, was in solution in ten grains of 
 water. 
 
 !• 275^ ro grain of arsenious acid, in one hundred grains of liquid, 
 or one part of the acid in the presence of 250,000 parts 
 of fluid, yields in a very little time a very fine deposit, 
 the inner portion of which has a brown color, while the 
 outer part has a bright, metallic luster. 
 
 2. 57000 grain, under a dilution of 500,000 parts of liquid, 
 
 yields much the same results as 1. 
 
 3. 10,000 grain, under a dilution of 1,000,000, yields a quite 
 
 good deposit. 
 
 4. 2 5,000 grain, under a dilution of 2,500,000, yields after some 
 
 minutes, a very satisfactory deposit. 
 
 5. 5 0,000 grain, in the presence of 5,000,000 parts of liquid, 
 
 yields after several minutes, a very distinct stain, the 
 outer part of which has a dark, metallic appearance, and 
 the inner, a brownish color. 
 In regard to the delicacy of this method, it may be remarked, 
 that in the whole range of chemical tests there is perhaps no 
 other that will indicate the presence of a substance under as 
 great a degree of dilution. It may be proper to state, that the 
 materials employed in the above experiments were subjected to 
 the action of the test for more than half an hour, without yield- 
 ing the slightest trace of a deposit in the reduction-tube. 
 
 Fallacies. — Antimonuretted hydrogen also is decomposed un- 
 der the above conditions, with the deposition of metallic anti- 
 mony. Since, however, antimonuretted hydrogen is decomposed 
 
288 ARSENIC. 
 
 at a lower temperature than the arsenuretted gas, the antimony 
 eliminated is always, in part at least and from dilute solutions 
 whoUy, deposited before reaching the part of the reduction-tube 
 to which, the flame is applied ; when it yields deposits on both 
 sides of the flame, the outer one is quite near the flame. On 
 the other hand, arsenic deposits about half or three-quarters of 
 an inch in advance, or on the outer side of the flame, and never 
 before reaching the part of the tube to which the heat is directly 
 applied. This difference in itself is quite sufficient to distin- 
 guish between these metals, when only one of them is present. 
 Again, the arsenical deposit has usually a bright, metallic luster, 
 whilst the antimonial has a dull and darker appearance. Very' 
 thin deposits of the two metals, however, may present very 
 similar appearances. 
 
 In regard to the action of heat and chemical reagents upon 
 these metallic deposits, they differ in the following respects : — 
 
 a. If the tube, removed from the apparatus, be heated at a 
 little distance from and on the inner side of the crust, and the 
 heat then slowly advanced to it, the arsenical deposit readily 
 volatilises and recondenses a little further on, in the form of 
 brilliant, octahedral crystals of arsenious acid. Under the same 
 circumstances, the antimonial deposit requires a much higher ' 
 temperature for its sublimation, and yields a white, amorphous 
 deposit, quite near the point to which the heat is applied. This 
 method wiU serve for the identification of very minute crusts of 
 the metals. The arsenical sublimate thus obtained, may be 
 further identified by its ready solubility in a few drops of hot 
 water, and by the resulting solution, when acidulated with 
 hydrochloric acid and treated with sulphuretted hydrogen gas, 
 yielding a yellow precipitate. These characters, however, only 
 reveal themselves in sublimates obtained from comparatively 
 thick crusts of the metal. 
 
 &. The deposits of the two metals may also be distinguished 
 by either a solution of sulphuret of ammonium, hypochlorite of 
 soda, or by dissolving the crust in nitric acid, evaporating the 
 solution to dryness, and treating the residue with nitrate of sil- 
 ver, in the manner already described for the discrimination of 
 stains obtained on porcelain from the ignited gas. 
 
MARSH'S TEST. 289 
 
 C. If a slow stream of perfectly dry sulphuretted hydrogen 
 gas be conducted through the tube containing the arsenical 
 deposit, and the latter heated by the flame of a spirit-lamp ap- 
 plied to the tube, beginning at the outer margin of the deposit, 
 it in vaporising is converted into tersulphuret of arsenic, which 
 condenses at a little distance in advance of the heat to a yel- 
 low deposit, the inner margin of which, even after cooling, 
 has sometimes an orange hue. The metallic deposit from the 
 5,000th part of a grain of arsenious acid, wiU in this manner 
 yield very distinct results. Under these same conditions, the 
 antimonial crust also decomposes the sulphuretted gas, with the 
 formation of tersulphuret of antimony, which however condenses 
 to a reddish-brown or nearly black deposit. To eifect this 
 change, requires a stronger heat than for the arsenical crust, 
 and the sulphuret formed, deposits much nearer the flame of the 
 lamp. In applying this method, it must be borne in mind that 
 sulphuretted hydrogen alone, especially if moist, may be decom- 
 posed by the heat with the deposition of globules of sulphur, 
 which while warm have a yellow color ; but when cold, they 
 have only a very faint yellow tint. The tersulphuret of arsenic 
 is readily distinguished from free sulphur in being soluble in 
 ammonia. When exposed to a slow current of dry hydrochloric 
 acid gas, tersulphuret of antimony readily disappears, whilst the 
 sulphuret of arsenic is unaffected by this gas. These methods 
 of distinguishing between these deposits, were first pointed out 
 by Pettenkofer, and Fresenius. 
 
 There is no other metal, besides arsenic and antimony, that 
 will, by this method of Marsh, yield a deposit in the heated 
 reduction-tube. Sulphur may yield a yellowish-white, and sele- 
 nium a reddish-brown stain ; but these stains could not be con- 
 founded with the arsenical deposit. 
 
 r- Decomposition by nitrate of silver. — If the reduction- 
 tube of the apparatus be substituted by a tube bent at a right 
 angle (Fig. 10, e), and the arsenuretted hydrogen conducted into 
 a solution of nitrate of silver, both the gas and the silver-salt 
 undergo decomposition, with the production of arsenious acid, 
 which remains in solution, and the elimination of metallic silver, 
 which falls, as a black precipitate. The reaction in this case is 
 
 19 
 
290 ARSENIC. 
 
 as foUows : AsH^ + 6 AgO, NO5 = 3 HO + AsO^ + 6 Ag + 6 NO5. 
 The resulting solution, therefore, contains arsenious acid and 
 free nitric acid, together with any excess of nitrate of silver 
 employed. In applying this test, which was first proposed by 
 Lassaigne, the current of gas should not be rapid, and only a 
 quite dilute solution of the silver-salt should at first be em- 
 ployed ; more of the salt may afterwards be added, if required. 
 The presence of the arsenious acid thus produced, may be 
 shown by either of the following methods : — 
 
 1. If the solution be filtered, and the filtrate exactly neu- 
 tralised with ammonia, it will yield a yellow precipitate of arsen- 
 ite of silver, having the properties already described. Should 
 the whole of the nitrate of silver have been decomposed by the 
 arsenuretted hydrogen, it will of course be necessary to add a 
 little of this salt, after the neutralisation by ammonia, before 
 the precipitate will appear. Since in the application of this 
 test, the neutralisation of the eliminated nitric acid will give 
 rise to nitrate of ammonia, in which the arsenite of silver is 
 sparingly soluble, the reaction will not be quite as delicate as 
 when the test is applied to a pure solution of arsenious acid. 
 
 2. If the excess of nitrate of silver in the filtered solution 
 be precipitated by slight excess of hydrochloric acid, the solu- 
 tion again filtered, and the filtrate treated with sulphuretted 
 hydrogen gas, it yields a bright yellow precipitate of tersul- 
 phuret of arsenic. The arsenic from the 1,000th part of a 
 grain of arsenious acid, can in this manner be recovered with- 
 out any appreciable loss. Instead of treating the solution with 
 sulphuretted hydrogen, after the removal of the excess of 
 nitrate of silver by hydrochloric acid, it may be examined by 
 Reinsch's test. 
 
 3. If, after the removal of the excess of nitrate of silver by 
 the cautious addition of hydrochloric acid, the filtrate be cau- 
 tiously evaporated to dryness, the arsenic will remain as a white 
 deposit of arsenic acid, which when moistened with a solution 
 of nitrate of silver, assumes a brick-red color. 
 
 Delicacy of this reaction, — In the following investigations, 
 the arsenious acid Avas dissolved in ten grains of pure water, 
 the solution placed in a small test-tube with a few fragments of 
 
FALLACIES OF MARSH'S TEST. 291 
 
 zinc, and then sufficient sulphuric acid added to evolve a slow 
 stream of gas. The gas thus evolved, was conducted into five 
 grains of a dilute solution of nitrate of silver. 
 !• Too" grain of arsenious acid, yields a gas that produces a 
 copious, black precipitate in the silver-solution. 
 
 2. iJoo grain, yields a good precipitate. 
 
 3. 10,0 grain : a black deposit soon appears in the immersed 
 
 end of the delivery-tube, and in a little time black flakes 
 appear on the surface of the silver-solution, 
 'i- 1 u 0% grain : after some minutes, a distinct deposit forms 
 in the lower end of the delivery-tube. 
 
 The delicacy of this reaction, depends partly upon the fact 
 that the arsenuretted hydrogen evolved from one part of arseni- 
 ous acid, eliminates six and a half parts of metallic silver. 
 
 Fallacies. — Nitrate of silver is also decomposed by antimon- 
 uretted hydrogen, with the production of a black precipitate. 
 In this reaction, however, as already pointed out [ante, p. 229), 
 the whole of the antimony, even to the last trace, is thrown 
 down as antimonide of silver. This method will, therefore, 
 serve to separate and detect arsenic in the presence of anti- 
 mony, even according to Dr. Hofmann, when the mixture con- 
 sists of one part of the former and one hundred and ninety -nine 
 parts of the latter metal, and only a minute quantity of the 
 mixture is examined. 
 
 So, also, will sulphuretted hydrogen and the hyduret of 
 phosphorus, produce black precipitates, in a solution of nitrate 
 of silver. It is obvious, therefore, that the mere production of 
 a black precipitate, in the silver solution, is not in itself direct 
 evidence of the presence of arsenic. 
 
 When arsenuretted hydrogen is passed into a solution of cor- 
 rosive sublimate, it produces a yellow or brownish-yellow pre- 
 cipitate, which according to H. Rose consists of SHg^Cl; As — the 
 reaction being, perhaps, AsHj + 6 Hg CI = 3 H CI + 3 Hgj CI ; As. 
 Antimonuretted hydrogen, under like circumstances, produces 
 a white, flocculent precipitate, which almost immediately turns 
 grey, then dark-grey or almost black. The reaction of the 
 arsenuretted gas is extremely delicate. Thus the gas evolved 
 from the 50,000th part of a grain of arsenious acid in ten grains 
 
292 ARSENIC. 
 
 of fluid, will produce a quite distinct yellow deposit in the lower 
 end of the delivery-tube. 
 
 Since arsenuretted hydrogen is thus decomposed by salts of 
 silver and of mercury, as well as by free chlorine, nitric acid, 
 and certain other substances, if either of these be present in 
 the flask in which the gas is being generated, the latter may be 
 entirely decomposed before leaving the apparatus. It is, there- 
 fore, obvious that if in the examination of a suspected mixture 
 by the method of Marsh, it should yield negative results, it 
 would not follow, from this fact alone, that arsenic was entirely 
 absent, even in a soluble form. 
 
 Quite recently M. Z. Roussin has recommended, for the evo- 
 lution of the hydrogen in the application of Marsh's test, to 
 substitute for the zinc, metallic magnesium, which may now be 
 obtained in its pure state. If this metal be employed, before 
 introducing the arsenical or suspected solution into the appara- 
 tus, the evolved gas should be examined by passing it through 
 the red-hot reduction-tube for about ten minutes, for the pur- 
 pose of testing its purity. This preliminary examination is 
 necessary, since magnesium is sometimes contaminated with 
 silicium, which might give rise to silicuretted hydrogen, with 
 the deposition of a dark brown deposit in the heated tube. 
 This deposit, however, differs from an arsenical crust in that it 
 is unaffected by nitric acid and a solution of a hypochlorite, it 
 being insoluble in these liquids. (London Chem. News, July, 
 1866, pp. 27, 42.) 
 
 Bloxam's Method. — When arsenious acid is present in a 
 mixture in which water is being decomposed by a galvanic cur- 
 rent instead of by zinc and sulphuric acid, the arsenical com- 
 pound is also decomposed by the . nascent hydrogen with the 
 formation of arsenuretted hydrogen gas. Professor Bloxam has 
 recently proposed this reaction as a ready means of detecting 
 arsenic, and as free from some of the objections that may be 
 urged against the method of Marsh. 
 
 The form of apparatus he employs, consists of a two-ounce 
 narrow-mouthed bottle, the bottom of which has been cut off. 
 
BLOXAM'S METHOD. 293 
 
 and replaced by a piece of vegetable parchment tightly stretched 
 over it and secured by a thin platinum wire. The bottle is 
 furnished with a cork, carrying a funnel-tube, and a small tiibe 
 bent at a right angle and connected with the reduction-tube by 
 a caoutchouc connection ; through the cork also passes a plati- 
 num wire bent into a hook, inside of the bottle, for suspending 
 the negative plate. The bottle is placed in a glass vessel of 
 such size as to leave a small interval between the two, and this 
 arrangement placed in a large vessel of cold water ; an ounce 
 of diluted sulphuric acid is then introduced into the apparatus, 
 so as to fill the bottle and the outer space to about the same 
 level, the positive plate being immersed in the acid contained 
 in this outer space. 
 
 The apparatus being thus adjusted, the terminal platinum 
 plates, each measuring about two inches by three-quarters of 
 an inch, are connected by means of broad strips of platinum- 
 foil, with a Grove's battery of five cells ; the one within the 
 bottle being connected with the zinc, and that in the outer ves- 
 sel with the platinum extremity of the battery. When the 
 bottle has become filled with hydrogen, the reduction-tube — 
 which may be constricted at several places — is heated to red- 
 ness for about fifteen minutes, to test the purity of the sulphuric 
 acid employed. The liquid to be tested is then introduced into 
 the bottle by means of the funnel-tube, and the gas evolved 
 examined in the same manner as in Marsh's method. If the 
 mixture froths, from the presence of organic matter, a little 
 alcohol may be added. The author of this method states that 
 by it, the 1,000th part of a grain of arsenious acid can be 
 detected in an organic mixture, with the greatest ease and 
 certainty. 
 
 When the poison exists in the form of arsenic acid, no ar- 
 senuretted hydrogen is evolved by this process. When in this 
 form, however, the arsenic may be made to respond to the test 
 by treating the solution, previous to its introduction into the 
 apparatus, with sulphurous acid gas or a few drops of a solu- 
 tion of bisidphite of soda, and heating on a water-bath, until 
 the sulphurous odor has disappeared. The introduction of a 
 few drops of a solution of sulphuretted hydrogen gas into the 
 
294 ARSENIC. 
 
 apparatus also serves to reduce the arsenic acid, as the arsenic 
 combines with the nascent hydrogen in preference to the sul- 
 phur; even when large excess of sulphuretted hydrogen is 
 employed, it does not interfere with the evolution of the arsen- 
 uretted gas. But under these circumstances, a deposit of sul- 
 phur may form in the reduction-tube outside of the arsenical 
 deposit, and the latter may consist partly of tersulphuret of 
 arsenic ; the sulphuret of arsenic may be distinguished from 
 free sulphur by its deep yeUow color, and ready solubility in a 
 warm solution of carbonate of ammonia, in which the sulphur 
 is insoluble. 
 
 The addition of sulphuretted hydrogen to the arsenical solu-^ 
 tion, under the above circumstances, would precipitate as a 
 sulphuret any antimony or mercury if present, in which form 
 neither of these metals interferes with the detection of arsenic. 
 Thus, Professor Bloxam states, the 1,000th part of a grain of 
 arsenious acid, converted into arsenic acid by the action of 
 hydrochloric acid and chlorate of potash, when mixed with one 
 grain of tartar emetic and excess of sulphuretted hydrogen, and 
 the mixture introduced into the decomposing cell, furnished in 
 the reduction-tube a distinct deposit of arsenic free from anti- 
 mony. Similar experiments made with mixtures of arsenious 
 acid and corrosive sublimate, furnished equally good results. 
 Without the addition of the sulphuretted hydrogen, the anti- 
 mony and mercury are- deposited upon the negative plate ; 
 when however a comparatively large quantity of the former 
 metal was present, it yielded a metallic mirror in the reduction- 
 tube. (Quart. Jour. Chem. Society, vol. xiii, pp. 12 and 338, 
 et seq.) 
 
 Other Eeactions of Arsenious Acid. — Various other tests 
 have been proposed for the detection of arsenious acid, but both 
 in regard to delicacy of reaction and freedom from fallacy, they 
 are much inferior to those already described. Among these 
 tests may be mentioned the following. 
 
 ]. Lime-ivater produces in solutions of the poison a white 
 precipitate of arsenite of lime, which is readily soluble in hydro- 
 chloric and most other acids. One grain of a 100th solution of 
 
IODINE AND REDUCTION TESTS. 295 
 
 arsenioijs acid, yields a copious, flocculent precipitate, which 
 sooa becomes graaular; a similar quantity of a 1,000th solu- 
 tion yields a very good, granular deposit ; and the same quan- 
 tity of a 5,000th solution, a slight cloudiness. The whole of 
 the arsenic may be withdrawn from the hydrochloric acid solu- 
 tion of the arsenite, by Reinsch's test. The lime reagent also 
 produces white precipitates in solutions of several other acids. 
 
 2. Iodide of potassium slowly throws down from concentrated 
 solutions of arsenious acid a white, granular precipitate, which 
 adheres tenaciously to the sides and bottom of the test-tube in 
 which the experiment is performed. The deposit, when treated 
 with hydrochloric acid, assumes a bright yellow color. Ten 
 grains of a 50th solution of the poison fail to yield with the 
 reagent a precipitate for several minutes ; after about an hour, 
 a copious deposit has formed. If after the addition of the re- 
 agent, the mixture be treated with large excess of hydrochloric 
 acid, it yields an immediate orange-yellow or yellow precipitate, 
 which is insoluble in hydrochloric acid, but readily soluble in 
 excess of arsenious acid. In this manner, the 100th part of a 
 grain of the poison in one grain of water, yields a copious, 
 orange-yellow deposit; and the 1,000th of a grain, a quite 
 good, yellow precipitate. If the arsenious acid be added to a 
 solution of iodide of potassium in large excess of hydrochloric 
 acid, the same yellow precipitate separates. 
 
 3. Bichromate of potash prodvices in quite concentrated solu- 
 tions of arsenious acid a green precipitate of sesquioxide of 
 chromium. This reaction is common to solutions of tartar 
 emetic and of several other substances. 
 
 4. When a solution of arsenious acid is treated with excess 
 of caustic potash and a drop of a solution of sulphate of copper, 
 the mixture on being boiled throws down a red precipitate of 
 suboxide of copper, due to the reducing action of the arsenious 
 acid, the latter remaining in solution as arsenic acid. In the 
 addition of the sulphate of copper, care should be taken to avoid 
 an excess, otherwise the mixture will also yield a black precip- 
 itate of protoxide of copper, which may mask the color of the 
 suboxide. Solutions of grape-sugar and of certain other sub- 
 stances, have a reducing action similar to that of arsenious acid. 
 
296 ARSENIC. 
 
 Separation from Organic Mixtures. 
 
 Suspected Solutions. — Since arsenious acid, under certain 
 conditions, is only sparingly soluble in water, before applying 
 any chemical tests to a suspected mixture containing solid or- 
 ganic matter, it should be carefully examined for solid particles 
 of the poison. If the mixture contain much mechanically sus- 
 pended matter, the whole may be placed in a large porcelain 
 dish, water added if necessary, and the mass thoroughly mixed ; 
 the larger organic! masses are then carefully removed, the re- 
 maining contents gently rotated in the dish, the supernatant 
 liquid decanted, and the residue carefully examined, by means 
 of a lens if necessary, for the solid poison. Any white masses 
 or particles thus found, are washed in pure water, and allowed 
 to dry. A very small portion of the dried mass is then heated 
 in a small reduction-tube, and any sublimate obtained examined 
 by the microscope. Other portions of the mass may be exam- 
 ined by any of the other tests already described for the recog- 
 nition of the poison in its solid state. So also, a portion may 
 be dissolved in water and the solution tested. 
 
 Whether the poison is thus discovered or not, the organic 
 solids are returned to the liquid and the whole intimately mixed, 
 the liquid then filtered, and the solids on the filter washed with 
 distilled water, the washings being added to the first filtrate. 
 Should the mixture presented for examination be thick from the 
 presence of organic matter, after the addition of water and be- 
 fore filtration, it may be acidulated with hydrochloric acid and 
 gently boiled for ten or fifteen minutes. The filtrate, obtained 
 by either of these methods, is concentrated to a convenient vol- 
 ume, measured, and a given portion set aside for a quantitative 
 analysis if necessary. Another portion, acidulated with hydro- 
 chloric acid, is boiled with a very small slip of bright copper- 
 foil, the latter not being added until the liquid has reached the 
 boiling temperature. If the copper quickly receive a coating, 
 it is removed from the liquid, and fresh slips of the metal added, 
 as long as they receive a deposit. Should, however, the copper 
 first added not receive a metallic coating, the boiling should be 
 
SEPARATION FROM ORGANIC MIXTURES. 297 
 
 continued until the liquid is evaporated to near dryness, before 
 it is concluded that the poison is entirely absent. Any slips of 
 copper that have thus become coated, are washed by the aid of 
 a gentle heat, first in pure water, then in water containing a 
 trace of ammonia, and again in pure water, then drained, placed 
 on filtering paper and dried in a water-bath. One or more of 
 the coated slips are then heated in an appropriate reduction- 
 tube, when the deposit, if consisting of arsenic, will yield a 
 sublimate of octahedral crystals of arsenious acid, readily iden- 
 tified by means of the microscope. 
 
 If the method now considered should fail to reveal the pres- 
 ence of arsenic, there would be little doubt of the entire absence 
 of the poison, unless, possibly, there was also some other sub- 
 stance present that interfered with its deposition lupon the cop- 
 per : at the same time, if the copper remained bright, it would 
 be quite certain that mercury and antimony also were absent. 
 
 Should it be desired to pursue the investigation, another 
 portion of the above filtrate may be examined after the method 
 of Marsh. Or, the liquid, acidulated with hydrochloric acid, 
 may be saturated with sulphuretted hydrogen gas, and allowed 
 to stand in a moderately warm place until the precipitate has 
 completely subsided ; the precipitate is then collected on a filtei", 
 washed, and, if it contains organic matter, purified in the man- 
 ner hereafter described. 
 
 Vomited matters. — These are carefully collected, and exam- 
 ined for any soKd particles . of the poison. The mass is then 
 diluted with water, strongly acidulated with hydrochloric acid, 
 and kept at thei boiling temperature for about twenty minutes ; 
 after the mixture has cooled, the Kquid is filtered, the filtrate 
 concentrated, and then examined in the manner directed above. 
 It need hardly be remarked, that a failure to detect the poison 
 in the vomited matters, would not in itself be conclusive evi- 
 dence th^t it had not been taken. 
 
 Contents of the Stomach. — Before proceeding to the prepara- 
 tion of the contents of the stomach, for the application of chem- 
 ical tests, they, as weU as the inside of the organ, should be 
 minutely examined for any of the poison in its solid state, in 
 the manner described above. Any white particles or powder 
 
298 ARSENIC. 
 
 thus found, are washed, dried, and tested in the usual manner 
 for the solid poison. The physical appearance and condition of 
 the stomach should also be carefully noted. 
 
 The contents are now placed in a clean porcelain dish, and 
 the inside of the stomach scraped and washed, the scrapings 
 and washings being added to the contents of the dish ; or, the 
 tissue itself may be cut into small pieces, and these added to 
 the contents. After the addition of water if necessary, the 
 mass is intimately mixed with about one-eighth of its volume 
 of pure hydrochloric acid, and maintained at near the boiling 
 temperature until the organic solids are entirely disintegrated. 
 The mixture is then allowed to cool, transferred to a clean 
 muslin strainer, and the matters retained by the strainer washed 
 with water : the strainer, with its contents, may be reserved for 
 future examination, if necessary. The strained liquid thus ob- 
 tained, if in large quantity, is concentrated at a moderate heat, 
 again allowed to cool, and then filtered. 
 
 A given portion of the filtrate thus obtained, is examined 
 by the method of Reinsch, successive slips of the copper being 
 added as long as they receive a deposit. Any pieces of the 
 metal that have thus become coated, after being thoroughly 
 washed and dried, are heated in a suitable reduction-tube, and 
 the result examined in the usual manner. 
 
 Another portion or the whole of the remaining filtrate, may 
 be exposed for several hours to a slow stream of sulphuretted 
 hydrogen gas, then gently warmed, and allowed to stand quietly, 
 until the supernatant liquid has become perfectly clear. If the 
 poison is present in considerable quantity, the > precipitate may 
 have a bright yellow color and consist of nearly pure tersul- 
 phuret of arsenic ; the color of the latter, however, may be 
 much modified by the presence of organic matter, which is 
 always more or less precipitated under these circumstances, 
 usually of a yellowish-brown color. 
 
 The precipitate thus produced is collected upon a small filter, 
 washed, and while still moist, digested with pure aqua ammonia: 
 this liquid will readily dissolve any sulphuret of arsenic present, 
 whilst the organic matter may remain undissolved. The ammo- 
 niacal solution is filtered, and the filtrate carefully evaporated 
 
SEPARATION FROM THE TISSUES. 299 
 
 at a moderate heat to dryness. The true nature of the residue 
 thus obtained, if consisting of tersulphuret of arsenic, may be 
 established by either of the methods heretofore pointed out, 
 under the special consideration of the sulphuretted hydrogen 
 test. Should, however, the residue contain organic matter and 
 only a minute quantity of the sulphuret, it may require further 
 purification before its arsenical nature can be satisfactorily de- 
 termined. Under these circumstances, the dried residue is col- 
 lected in a thin porcelain dish or crucible, moistened with a 
 few drops of concentrated nitric acid, and treated in the man- 
 ner described hereafter, for the purification of the sulphuretted 
 hydrogen precipitate obtained from the tissues. 
 
 The contents of the intestines may be examined in the same 
 manner as the contents of the stomach. Sometimes, the poison 
 may be detected in these when there has been a failure to show 
 its presence in the stomach. 
 
 From the Tissues. — Whether the examination of the con- 
 tents of the stomach or of the intestines have revealed the 
 presence of arsenic or not, an examination of the tissues or 
 fluids of the body, for the absorbed poison, should not be omit- 
 ted. Any poison found under these circumstances would be 
 that which had entered the circulation and had its share in pro- 
 ducing death ; whereas, this would not be the case with that 
 found in the contents of the stomach or intestines. Moreover, 
 it sometimes happens that the poison is absent from the ali- 
 mentary canal, and yet readily detected in some of the tissues. 
 Absorbed arsenic is deposited, to a greater or less extent, in all 
 the soft tissues of the body, and any of these may be made the 
 subject of analysis ; the greatest relative quantity, however, is 
 usually found in the liver. The absolute quantity thus found, 
 even under the most favorable circumstances, rarely exceeds a 
 grain in weight. 
 
 For the recovery of absorbed arsenic from the tissues, vari- 
 ous methods have been proposed. In many instances, this may 
 be eflfected by simply boiling the finely divided tissue with 
 diluted hydrochloric acid, until the organic matter is well disin- 
 tegrated, and then employing the method of Reinsch. In this 
 manner, we have, in several instances, recovered sufficient of 
 
300 ARSENIC. 
 
 the poison from the liver to permit its confirmation by all the 
 other tests. The more certain method of proceeding, however, 
 is to entirely destroy, or at least carbonise, the organic matter, 
 before applying any tests. For this purpose, the following 
 methods have been advised. 
 
 1. Fresenius and Babo proposed to destroy the organic mat- 
 ter by means of hydrochloric acid and chlorate of potash. The 
 solid tissue, as about one-fourth of the liver, is cut into very 
 small pieces, the mass' placed in a clean porcelain dish, then 
 treated with an amount of pure hydrochloric acid somewhat 
 exceeding the weight of the dry, solid matter present, and 
 sufficient water to form the whole into a thin paste. The dish, 
 with its contents, is then heated on a water-bath, and about 
 twenty grains of powdered chlorate of potash added to the hot 
 liquid, and the addition repeated, with frequent stirring, every 
 several minutes, until the mass becomes perfectly homogeneous, 
 and of a light yellow color ; the whole is then heated until the 
 odor of chlorine has entirely disappeared : during this process, 
 a little water should be occasionally added, to prevent concen- 
 tration of the mixture. When the liquid mass has entirely 
 cooled, it is transferred to a linen strainer, and, after the whole 
 of the fluid has passed, the solid residue washed with warm 
 water, the washings being collected separately. They are now 
 concentrated on a water-ba,th to a small volume, allowed to cool, 
 and then added to the first-strained fluid, and the mixed liquids 
 filtered through paper. Any arsenic originally present, will 
 now exist in the filtrate as arsenic acid. 
 
 The filtrate thus obtained, is treated with a solution of bisul- 
 phite of soda, or exposed to a slow stream of sulphurous acid 
 gas — prepared by boiling slips of copper with concentrated sul- 
 phuric acid — until it smells strongly of the gas ; it is then 
 gently heated, until the sulphurous odor has entirely disap- 
 peared. By this treatment, any arsenic acid present will be 
 reduced to arsenious acid, in which form the metal is not only 
 much more rapidly, but also, as we know from direct experi- 
 ment, more completely precipitated by sulphuretted hydrogen, 
 than when it exists in the form of arsenic acid. The solution, 
 supposed to contain arsenious acid, may now be concentrated 
 
SEPARATION FROM THE TISSUES. 301 
 
 on a water-bath at a temperature not exceeding 160° F., to' 
 about three times the volume of hydrochloric acid employed in 
 its preparation^'then allowed to stand in a cool place for several 
 hours, and any deposit that forms, removed by a filter. 
 
 The liquid is next placed in a convenient vessel, and a slow 
 stream of washed sulphuretted hydrogen gas transmitted through 
 it for several hours ; it is then gently heated, and allowed to 
 stand in a moderately warm place for from twelve to twenty- 
 four hours. The whole of the arsenic, if present, will thus be 
 precipitated as tersulphuret of the metal, together with more or 
 less organic matter. Should the hquid have contained mercury, 
 antimony, copper or lead, these metals would also be precipi- 
 tated, as sulphurets, by the sulphuretted hydrogen. It must be 
 borne in mind, that liquids prepared as the above, usually yield 
 with sulphuretted hydrogen a brownish or yellowish precipitate 
 of organic matter, even in the absence of any metal. The pre- 
 cipitate is now collected upon a small filter, and washed, at first 
 with water containing a little sulphuretted hydrogen, until' the 
 washings no longer contain chlorine. 
 
 jFor the purification of the precipitate thus obtained, different 
 methods have been proposed. The following method, advised 
 by Professor Otto, has in our hands furnished the most satis- 
 factory results. The filter containing the moist precipitate is 
 spread out in a porcelain dish, and the precipitate stirred first 
 with sufficient water to make a thin paste, then with excess of 
 pure aqua ammonia. Any sulphviret of arsenic present, together 
 with more or less of the organic matter, will be readily dissolved 
 by the ammoniacal liquid, while the sulphurets of the other poi- 
 sonous metals mentioned above, which might be present, would 
 remain unchanged : it is usually stated that a portion of sul- 
 phuret of antimony, if present, might also be dissolved, but we 
 have already shown that this compound, at least in its pure 
 state, requires about 20,000 times its weight of aqua ammonia 
 for solution. The ammoniacal mixture is then transferred to a 
 small, moistened filter, and the solid residue washed with diluted 
 ammonia, the washings being collected with the first filtrate. 
 The filter, with its contents, should be reserved for future ex- 
 amination, if necessary. 
 
302 ARSENIC. 
 
 The ammoniacal filtrate, which has usually a' dark brown 
 color, is now placed in a small porcelain capsule or thin evapo- 
 rating dish, and evaporated to dryness on a water-bath ; after 
 this the residue is treated with a small quantity of concentrated 
 nitric acid, and the mixture again evaporated to dryness, this 
 operation with nitric acid being repeated, if necessary, until 
 the moist residue has a yellow color. The residue is then 
 moistened with a few drops of a concentrated solution of caustic 
 soda, a small quantity of pure powdered carbonate of soda and 
 nitrate of soda added, and the well-mixed mass cautiously evap- 
 orated to dryness; the heat is then very gradually increased 
 until the mass becomes colorless, when the organic matter will 
 be entirely destroyed. In the performance of the operations 
 now described, it is of the utmost importance that the nitric 
 acid and compounds of soda employed be perfectly free from 
 chlorine, since otherwise a portion or the whole of the arsenic 
 may be volatilised in the form of chloride. 
 
 Any arsenic present will now exist, in the above incinerated 
 residue, as arsenate of soda, mixed with more or less nitrate, 
 nitrite, carbonate, and sulphate of soda, the latter salt being 
 derived from the oxidation of the sulphur. This mixture, when 
 cooled, is dissolved in a small quantity of warm water, and the 
 solution, after filtration if necessary, strongly acidulated with 
 pure sulphuric acid, then evaporated until dense white fumes of 
 sulphuric acid are evolved. By this treatment, the carbonic, 
 nitric, and nitrous acids will be entirely expelled, the soda com- 
 bined with them uniting with the sulphuric acid to sulphate of 
 soda: the solution wiU, therefore, contain only sulphate of soda, 
 and arsenate of soda, if present. Should there be any doubt 
 as to the entire expulsion of the nitric and nitrous acids, a little 
 more sulphuric acid is added, and the solution again evaporated. 
 
 A portion of the strongly acid liquid thus obtained, may 
 now be introduced into an active Marsh's apparatus, and the 
 evolved gas examined in the manner already described. Before 
 submitting any remaining portion of the suspected liquid to the 
 action of any of the other tests, it should be diluted somewhat, 
 and the arsenic acid reduced to arsenious acid, by sulphurous 
 acid gas, in the manner directed above; the solution may then. 
 
SEPARATION FROM THE TISSUES. 303 
 
 if thought best, be again concentrated. A portion of the solu- 
 tion may now be examined by the method of Reinsch ; and 
 another portion submitted to the action of sulphuretted hydrogen 
 gas. Any sulphuret of arsenic precipitated from a solution of 
 this kind, especially if only a small quantity of the metal be 
 present, will usually have a more or less orange hue. The 
 arsenical nature of any sulphuret of arsenic thus obtained, may 
 be confirmed by any of the methods heretofore described, espe- 
 cially by the process of reduction. If the first examination of 
 the suspected liquid, by Marsh's method, indicate the presence 
 of a comparatively large quantity of arsenic, a given portion 
 of the solution should be employed for the application of the 
 sulphuretted hydrogen test, and the quantity of the sulphuret 
 thus obtained estimated in the manner hereafter described. If 
 any of the suspected solution, that has been treated with sul- 
 phurous acid gas, still remain, and it be desired to apply the 
 silver and sulphate of copper tests, a small quantity of the liquid 
 is exactly neutralised by caustic soda or carbonate of soda, then 
 divided into two, about equal parts, to one of which a solution 
 of nitrate of silver, and to the other a solution of sulphate of 
 copper is added, when any arsenic present will yield its appro- 
 priate precipitates. Since, under the circumstances just men- 
 tioned, the arsenic would exist in the neutralised liquid as an 
 alkaline arsenite, the ammonio-compounds of the silver and 
 copper salts should not be employed. 
 
 The method now described for the disintegration of the tis- 
 sues, and the subsequent purification of the precipitate produced 
 by sulphuretted hydrogen, is, according to our experience, much 
 the best yet proposed for the recovery, at least of minute traces, 
 of absorbed arsenic. At the same time, it has the advantage 
 of excluding mercury, antimony, and certain other poisonous 
 metals, from the solution tested for arsenic, and yet provides 
 for their detection if present in the substance submitted to 
 examination. In illustration of the delicacy of this process, in 
 regard to the purification of the sulphuretted hydrogen pre- 
 cipitate, the following experiment may be cited. A partially 
 decomposed liver, free from arsenic, was boiled with diluted 
 hydrochloric acid and chlorate of potash, until the organic 
 
304 ARSENIC. 
 
 matter was well dissolved, and to one thousand fluid-grains of 
 the complex mixture thus obtained, the 100th j)art of a grain 
 of arsenious acid, in solution, was added, — the poison forming 
 only the 100,000th part of the mixture. The mixture was 
 then gently heated, allowed to cool, and the strained liquid 
 treated with a slow stream of sulphuretted hydrogen for twenty- 
 four hours; the precipitate thus obtained — which purposely 
 contained an excess of organic matter — was then treated as 
 described above, when the final solution, after treatment with 
 sulphurous acid gas, gave with several reagents, results that 
 could scarcely be distinguished from those obtained from an 
 equal volume of pure water containing the 100th of a grain of 
 the poison. 
 
 For the purification of the above sulphuretted hydrogen 
 precipitate, Fresenius recommends, to moisten it, together with 
 the filter, with fuming nitric acid, evaporate to dryness on a 
 water-bath, moisten the residue with warmed concentrated sul- 
 phuric acid, then heat it for two or three hours on a water- 
 bath, and finally on an oil-bath to a temperature of about 338° 
 F., imtil the charred mass becomes friable, and a sample of it 
 no longer imparts a color when mixed with water. The mass 
 is then warmed with a mixture of eight parts of water and one 
 part of hydrochloric acid, the solution filtered, the filtrate pre- 
 cipitated by sulphuretted hydrogen, the precipitate collected on 
 a small filter, washed, redissolved in ammonia, the ammoniacal 
 solution evaporated to dryness, and the residue weighed. The 
 residue may then be reduced by a mixture of cyanide of potas- 
 sium and carbonate of soda, in an atmosphere of carbonic acid 
 gas, in the manner already described. 
 
 In this connection it may be remarked, that the soft animal 
 tissues may be broken up and dissolved by heating them, after 
 being cut into small pieces, with diluted hydrochloric acid alone, 
 without the subsequent addition of chlorate of potash. But 
 under these circumstances, they require prolonged heating,' and 
 the resulting solution when strained, is apt to be viscid and 
 have a very dark or nearly black color, both of which are 
 objectionable if the liquid is to be subsequently treated with 
 sulphuretted hydrogen. A more serious objection, however, is 
 
SEPARATION FROM THE TISSUES. 305 
 
 that if arsenic be present in the form of sulphuret, which is not 
 unfrequently the case when the parts have undergone putrefac- 
 tion, the whole of it may escape solution. To a liquid prepared 
 in this manner, the method of Reinsch may, of course, be 
 directly applied; whereas, this will not be the case, when the 
 solution has been prepared by means of chlorate of potash. 
 
 That the method of Reinsch will serve to recover very 
 minute quantities of the poison from complex solutions, is well 
 illustrated by the following experiment. The 1,000th part of a 
 grain of arsenious acid, in solution, was added to one hundred 
 fluid-grains of the complex mixture obtained by boiling a 
 stomach with its contents, free from arsenic, with diluted 
 hydrochloric acid. The mixture was then boiled with a small 
 slip of bright copper-foil, when after a little time, the foil 
 received a very good steel-like coating, which when heated 
 in a small contracted reduction-tube, furnished a fine octahedral 
 crystalline sublimate, very similar to that obtained in, a like 
 manner, from the 100th of a grain of the poison in solution 
 in one hundred grains of pure acidulated water. It will be 
 observed that in this case the poison was difiused in 100,000 
 times its weight of the organic Uquid. 
 
 2. Danger and Flandin proposed to destroy the organic 
 matter of the tissues by means of concentrated sulphuric acid. 
 The organic tissue, cut into small pieces, is treated with about 
 one-fourth its weight of the concentrated acid, and the mixture 
 heated in a porcelain dish, until the black pasty mass first pro- 
 duced, becomes dry and carbonaceous; the cooled mass is then 
 treated with a little concentrated nitric acid, or aqua regia, and 
 again evaporated to dryness. The mass is now treated with 
 boiling water, the solution acidulated with nitric acid, then 
 evaporated to dryness, the residue moistened with nitric acid, 
 and the liquid again expelled by a moderate heat, this operation 
 with nitric acid being repeated, if necessary, until the mass 
 ' becomes colorless. The mass is then dissolved in a little water, 
 the solution neutralised with carbonate of soda, evaporated to 
 dryness, and the residue again heated with a few drops of con- 
 centrated sulphuric acid. Any arsenic present will now exist 
 as arsenate of soda. The residue is then dissolved in a small 
 
 20 
 
306 ARSENIC. 
 
 quantity of warm water, and the solution examined by the 
 method of Marsh; or, the solution may be saturated with sul- 
 phurous acid gas, and, after gently heating the liquid to expel 
 the excess of gas, treated with sulphuretted hydrogen. 
 
 The objection to the method of Danger and Flandin, is that 
 if a chloride, as chloride of sodium, or common salt, be present, 
 the carbonisation with sulphuric acid may give rise to the vola- 
 tilisation, in the form of terchloride, of any arsenic present. 
 The same objection would hold against the employment of aqua 
 regia in the process. To meet these objections, it has been 
 proposed to conduct the operations in a retort connected with a 
 well-cooled receiver. 
 
 3. Duflos and Hirsch, in 1842, advised to treat the finely 
 divided tissue, placed in a retort, with about an equal weight 
 of pure concentrated hydrochloric acid. A cooled receiver, con- 
 taining a little water, is then connected with the retort, and the 
 latter heated on a chloride of calcium bath, until the contents 
 become of a pasty consistency. This residue is mixed with 
 about twice its weight of strong alcohol, the mixture allowed to 
 digest some time, the liquid then strained through muslin, and 
 the solid matter well washed with fresh alcohol. The mixed 
 alcoholic liquids are filtered, and the filtrate distilled in a- retort, 
 until the alcohol passes off, after which the residue is mixed with 
 the acid contents of the receiver of the first distillation. This 
 mixture, after cooling, is treated with sulphuretted hydrogen, 
 when any arsenic present will be precipitated as tersulphuret. 
 
 Since arsenious acid, when heated with concentrated hydro- 
 chloric acid, is converted into terchloride of arsenic, which is 
 volatile, it has recently been proposed to take advantage of this 
 fact for the complete separation of the poison from the tissues, 
 as well as from organic mixtures generally. The finely divided 
 tissue, or the residue obtained by evaporating the suspected 
 organic solution to dryness, is thoroughly dried on a water-bath, 
 then placed in a retort with about its own weight of concentrated 
 hydrochloric acid, and the mixture distilled on a sand-bath, to 
 almost dryness, the distillate being collected in a well-cooled 
 receiver, containing a little water; the residue in the retort may 
 be redistilled with a fresh portion of the acid. 
 
FAILURE TO DETECT. 307 
 
 The distillate thus obtained, contains the arsenic as terchlo- 
 ride, together with a large quantity of free hydrochloric acid, 
 and more or less organic matter. A portion of the distillate 
 may be examined after the method of Reinsch. The remaining 
 liquid, diluted if necessary, is examined by the sulphuretted 
 hydrogen test, or by the process of Marsh, or both, and the 
 results confirmed in the ordinary manner. Since the liquid 
 contains a large quantity of free hydrochloric acid, this may 
 interfere with the detection of minute traces of the poison by 
 the method of Marsh. The only metals, besides arsenic, that 
 could, under these circumstances, appear in the distillate, are 
 antimony, bismuth, and, perhaps, tin. Should the arsenic exist, 
 in the substance subjected to distillation, in the form of sulphu- 
 ret, it would not appear in the distillate. Under these circum- 
 stances, the residue- in the retort may be heated with diluted 
 hydrochloric acid and the occasional addition of chlorate of 
 potash, until the organic matter is destroyed; the resulting 
 solution is then treated with sulphurous acid gas, and subse- 
 quently with sulphuretted hydrogen, in the manner heretofore 
 described. 
 
 The Urine. — No special method of analysis is required for 
 the separation of arsenic from the urine. The liquid may be 
 concentrated to a small volume, strongly acidulated with hydro- 
 chloric acid, and examined after the method of Eeinsch, a 
 minute fragment of the copper-foil being at first employed. Or, 
 the liquid may be evaporated to dryness on a water-bath, and 
 the organic matter of the dry residue, destroyed by means of 
 hydrochloric acid and chlorate of potash, in the usual manner. 
 This secretion seems to be the principal channel through which 
 arsenic is elimiaated from the system. In a case related by 
 Dr. Maclagan, he detected a trace of the poison in twenty-six 
 otmces of urine, as late as the twenty-first day after it had 
 been taken. 
 
 Failure to detect the Poison. — When arsenic is taken into 
 the stomach, it is rapidly absorbed and dififused through the 
 system, and after a time entirely eliminated from the living 
 body. From experiments on inferior animals, Orfila concluded 
 
308 ARSENIC. 
 
 that if there is no suppression of the natural secretions, the 
 poison will, in this manner, be entirely removed from the body 
 in about fifteen days; and this view has been sustained by 
 observations on the poisoned human subject. Independent of 
 the- action of absorption, the poison may, of course, be rapidly 
 removed from the stomach and intestines, by vomiting and 
 purging. Thus, Dr. Taylor relates a case in which no arsenic 
 was found in the stomach of an individual who died in eight 
 hours after taking nearly two ounces of the poison. (On Poisons, 
 p. 411.) So, also, instances are reported in which death took 
 place within a few days after the taking of the poison, and none 
 of it was found in any part of the body. The liver, as hereto- 
 fore stated, seems to be the organ in which the absorbed poison 
 is principally deposited. According to the observations of Dr. 
 Geoghegan, this organ usually receives its greatest quantity in 
 about fifteen hours after the poison has been taken, when it 
 may contain as much as two grains. It must be remembered, 
 however, that the poison may be absent from the liver, and yet 
 be present in some of the other organs of the body. In a case 
 related by Professor Casper (Forensic Medicine), in which death 
 occurred in twenty-four hours, arsenic, both in its solid state 
 and in solution, was readily discovered in the contents S)i the 
 stomach, but neither the blood nor the liver revealed its 
 presence. 
 
 Detection after long periods. — If arsenic be present in the 
 body at the time of death, the metal being indestructible, it 
 may be recovered after very long periods. A case has already 
 been mentioned in which we detected the poison, both in its 
 absorbed state and in the stomach, in a body that had been 
 buried seventeen months. And M. OUivier relates a case in 
 which it was detected after the lapse of three years. In a 
 case quoted by Dr. Beck, the body had been buried for seven 
 years. At this time, the body was entire^ the head, trunk, 
 and shoulders had preserved their form and position, but the 
 internal organs of the chest and abdomen were destroyed, and 
 there only remained a mass of soft, brownish matter, which was 
 deposited along the sides of the spine. A chemical examination 
 of this matter, by MM. Ozanam and Idt, readily revealed 
 
QUANTITATIVE ANALYSIS. 309 
 
 the presence of arsenic. (Med. Jur., ii, p. 594.) So, also, the 
 poison has been recovered after the lapse of eight, ten, and 
 twelve years respectively. And Dr. J. W. Webster, of Boston, 
 found four grains of arsenic in the body of a woman that had 
 been buried in a vault for fourteen years. This seems to be 
 the longest period yet recorded after which the poison has been 
 discovered in the dead body. 
 
 Since arsenic exists in certain soils, it is sometimes objected, 
 when the poison is detected in an exhumed body, that it may 
 have been derived from the surrounding earth. This objection 
 however has no practical force, unless only a very minute quan- 
 tity of the poison has been discovered and the parts of the body 
 examined were commingled with the earth. Under these cir- 
 cumstances,, a portion of the earth may be separately examined, 
 for the poison. The quantity of arsenic present in arsenical 
 soUs, according to various observers, never exceeds a mere 
 trace, and, in most instances at least, it can be extracted only 
 by the stronger mineral acids. 
 
 Quantitative Analysis. — Arsenic, when in solution in the 
 form of arsenious acid, is most readily estimated as tersulphuret 
 of the metal. For this purpose, the solution is acidulated with 
 hydrochloric acid, and a slow stream of washed sulphuretted 
 hydrogen gas passed through it, as long as a precipitate is pro- 
 duced ; the mixture is then gently heated, and allowed to stand 
 in a moderately warm place, until the precipitate has completely 
 subsided, and the supernatant liquid has become perfectly clear. 
 The precipitate is then collected on a small filter of known 
 weight, well washed, at first with water containing a Kttle sul- 
 phuretted hydrogen, thoroughly dried on a water-bath at 212° 
 F., and weighed. 
 
 One hundred parts by weight, of dry tersulphuret of arsenic, 
 correspond to 80"4:8 parts of pure arsenious acid. A portion 
 of the dried precipifate, when heated in a reduction-tube, should 
 completely volatilise, without either charring or leaving any 
 residue; otherwise it is not perfectly free from foreign matter. 
 
 The quantity of arsenious acid present in an organic liquid, 
 is most readily estimated by introducing the solution into an 
 
310 ARSENIC ACID. 
 
 active Marsh's apparatus, containing just sufficient sulphuric 
 acid to evolve a very slow stream of gas, and conducting the 
 evolved gas into a properly diluted solution of nitrate of silver. 
 The whole of the arsenuretted hydrogen thus evolved, as already 
 pointed out, will be reconverted by the silver-salt, into arseni- 
 ous acid, which will remain in solution, while metallic silver 
 will be thrown down as a black precipitate. When the evolved 
 gas has ceased to yield any further precipitate, the silver-solu- 
 tion, containing the arsenious acid, is filtered, and the excess 
 of the metal precipitated, by the cautious addition of hydro- 
 chloric acid, as chloride of silver; this salt is then separated 
 by a filter, previously moistened with water, and the filtrate, 
 after concentration on a water-bath if necessary, treated with 
 sulphuretted hydrogen, in the usual manner. 
 
 If, in the above operation, a comparatively large quantity 
 of nitrate of silver has been decomposed by the arsenuretted 
 gas, the solution may contain so much free nitric acid as to 
 decompose the sulphuretted hydrogen, and thus interfere with 
 the results. Under these circumstances, the solution should be 
 neutraHsed by caustic soda, and then acidulated with hydro- 
 chloric acid, previously to being treated with sulphuretted hy- 
 drogen ; and the precipitate produced by the latter, digested 
 with diluted aqua ammonia, the ammoniacal solution filtered, 
 the filtrate evaporated to dryness in a watch-glass on a water- 
 bath, thoroughly dried, and weighed. 
 
 III. Arsenic Acid. 
 
 GrENERAL CHEMICAL NATURE. — Arsenic acid is a compound 
 of one equivalent of metallic arsenic with five equivalents of 
 oxygen (AsOs). In its pure state, it is a white, odorless, deli- 
 quescent solid. When perfectly dry, it is only slowly soluble 
 in water; but ia its moist state, it is very readily soluble in 
 that menstruum. Its aqueous solutions are colorless, and have 
 a strongly acid reaction, quickly reddening litmus ; this reaction 
 is quite distinct in a solution containing only the 10,000th part 
 of its weight of the free acid. When an aqueous solution of 
 arsenic acid is treated with sulphurous acid gas, the arsenic 
 
SPECIAL CHEMICAL PROPERTIES. 311 
 
 acid is reduced to arsenious acid, and the sulphurous acid ox- 
 idised to sulphuric acid: ASO5 + 2 S02 = ASO3 + 2 SO3. When 
 exposed to a red heat, arsenic acid fuses, and is slowly dis- 
 sipated, being resolved into arsenious acid and free oxygen : 
 
 Arsenic acid, like common phosphoric acid, is tribasic, or 
 capable of uniting with three equivalents of a metallic base ; 
 and one, or two equivalents of the base, may be replaced by 
 corresponding equivalents of water. The arsenates of the alka- 
 lies are, for the most part, readUy soluble in water ; the other 
 metallic arsenates are insoluble in water, but soluble in sul- 
 phuric, nitric, and hydrochloric acids. The arsenates of the / 
 fixed alkalies, containing two, or three equivalents of base for 
 each equivalent of acid, withstand a strong red heat without 
 decomposition ; but when they contain only one equivalent of 
 base, they are reduced to the bibasic or tribasic form, a portion 
 of the acid being decomposed and evolved in the form of free 
 oxygen and arsenious acid. Under the action of heat, arsenic 
 acid displaces aU volatile acids from their basic combinations. 
 
 In regard to its physiological effects, arsenic acid appears, 
 from the observations of several experimentalists, to be even 
 more poisonous than arsenious acid. As yet, however, there 
 seems to be no instance of poisoning by it in its free state, in 
 the human subject. But several instances of poisoning by the 
 arsenate of potash and of soda, are reported. The symptoms 
 observed in these cases, were much the same as those usually 
 produced by arsenious acid. The treatment and post-mortem 
 appearances are also much the same. 
 
 Special Chemical Properties. — When a mixture of arsenic 
 acid or of an arsenate, and carbonate of soda, is heated on a 
 charcoal support, in the inner blow-pipe flame, the arsenical 
 compound is reduced and evolves the peculiar garlic-like odor 
 of the vaporised metal. When arsenic acid or any of its com- 
 pounds is intimately mixed with a reducing agent, as ferrocy- 
 anide of potassium, and the thoroughly dried mixture heated 
 in a reduction-tube, it yields a sublimate of metallic arsenic, 
 similar to that obtained under like circumstances from arse- 
 nious acid. 
 
312 ARSENIC ACID. 
 
 When a drop of an aqueous solution of free arsenic acid is 
 allowed to evaporate spontaneously to dryness, the residue usu- 
 ally consists of a gummy mass ; if, however, the evaporation 
 has taken place very slowly, the acid is left chiefly in the form 
 of long, slender, crystalline needles. If the residue thus ob- 
 tained, be moistened with water and exposed to sulphuretted 
 hydrogen gas, it acquires a yellow color, due to the formation 
 of sulphuret of arsenic ; when moistened with a yellow solution 
 of sulphpret of ammonium, and the mixture cautiously evap- 
 orated to dryness, it leaves a pale yellow residue, consisting of 
 pentasulphuret of arsenic, mixed with more or less free sulphur. 
 Nitrate of silver converts the arsenic acid residue into a red 
 brown deposit of tribasic arsenate of silver, which s6ems to 
 have a tendency to crystallise. Under this action of nitrate of 
 silver, the 1,000th part of a grain of arsenic acid yields a very 
 good red brown deposit; and the 10,000th of a grain, a quite 
 distinct reddish-brown coloration. 
 
 In the following examinations in regard to the behavior of 
 solutions of arsenic acid, pure aqueous solutions of the free 
 acid were employed. 
 
 1. Sulphuretted Hydrogen. 
 
 Normal solutions of arsenic acid, even when highly concen- 
 trated, fail to yield an immediate precipitate, when treated with 
 sulphuretted hydrogen gas ; but sooner or later, the mixture 
 becomes turbid, and after some hours, yields a light yellow pre- 
 cipitate, the color of which is much lighter than that of the 
 precipitate produced from solutions of arsenious acid. From 
 solutions acidulated with hydrochloric acid, the precipitate sepa- 
 rates more promptly, but even under these conditions, there is 
 no immediate deposit. The precipitate, according to Wacken- 
 roder, consists of a mixture of free sulphur and tersulphuret of 
 arsenic, the sulphuretted hydrogen first reducing the arsenic 
 acid to arsenious acid, and the latter then being decomposed, 
 and the metal precipitated as tersulphuret : AsOj + 5 HS = 5 HO 
 + §2 + AsSs. The formation of the precipitate is much facili- 
 tated by a gentle heat. 
 
SULPHURETTED HYDROGEN TEST. 313 
 
 The precipitate, thus produced, is insoluble in hydrocUoric 
 acid, but readily soluble, to a clear and colorless solution, in^ 
 aqua ammonia, as well as in the sulphurets and carbonates of 
 that alkali. • It is also soluble in the fixed caustic alkalies, and 
 in their carbonates and sulphurets ; the fixed alkaHes and their 
 carbonates, however, leave a little free sulphur undissolved, 
 which imparts to the solution a slight turbidity. If either of 
 these solvent substances be present in the solution, the reagent 
 will, of course, fail to produce a precipitate. 
 
 In the following experiments, in regard to the limit of this 
 test, ten fluid-grains of the arsenical solution, placed in a small 
 test-tube, were acidulated with two drops of concentrated hydro- 
 chloric acid, and treated with a slow stream of washed sulphu- 
 retted hydrogen gas. 
 
 1. 100th solution (= xo grain of arsenic acid), yields no imme- 
 
 diate change, but in about five minutes the solution be- 
 comes slightly turbid, and in about five minutes more, a 
 strong, yellow turbidity appears ; if the mixture be now 
 allowed to stand for a few hours, a quite copious, pale 
 yellow precipitate separates. 
 
 A similar quantity of a normal solution of the acid, 
 when treated with the reagent, becomes turbid in about 
 the same time as an acidulated solution, but fails to yield 
 a precipitate, even after standing many hours. 
 
 2. 1,000th solution, when saturated with the sulphuretted gas, 
 
 undergoes no perceptible change for about half an hour ; 
 the liquid then becomes turbid, and after several hours 
 lets fall a good precipitate. 
 
 3. 10,000th solution: no perceptible change for some hours; 
 
 after about eighteen hours, a quite perceptible, yellowish 
 precipitate has formed. 
 The arsenical nature of the precipitate produced by this 
 reagent, may be established by either of the following methods. 
 a. When the precipitate is boiled with diluted hydrochloric acid 
 and a slip of bright copper-foil, the latter slowly receives a coat- 
 ing of metallic arsenic. 6. If the precipitate be thoroughly 
 dried and heated in a reduction-tube, it first fuses, then whoUy 
 volatilises, yielding a viscid globular sublimate. The lower 
 
314 ARSENIC ACID. 
 
 margin of this sublimate, while still warm, has a dark color, 
 while the central portion appears red, and the upper margin 
 yellow ; when cool, the whole of the sublimate assumes a yeUow 
 color, which in the upper portion of the deposit is- quite pale, 
 c. When dried and heated in a reduction-tube, with a mix- 
 ture of cyanide of potassium and carbonate of soda, or with 
 ferrocyanide of potassium, it yields a sublimate of metallic 
 arsenic. 
 
 On comparing the above results, obtained from solutions of 
 arsenic acid by sxdphuretted hydrogen, with those obtained from 
 solutions of arsenious acid {ante, p. 263), it is obvious that the 
 former acid is much more slowly and less completely precipi- 
 tated by the reagent than the latter. When, therefore, the poi- 
 son exists in the form of arsenic acid, before applying the 
 reagent, it should be reduced to arsenious acid, by saturating 
 the solution with sulphurous acid gas, and gently heating the 
 liquid, until the odor of the gas has entirely disappeared. 
 
 2. Ammonio-Sulphate of Copper. 
 
 This reagent produces in normal solutions of arsenic acid, 
 a greenish-blue, amorphous precipitate of arsenate of copper 
 (2 CuO; HO, AsOs). The same precipitate is produced from 
 solutions of neutral arsenates, by sulphate of copper alone, but 
 this reagent fails to produce a precipitate in solutions of the free 
 acid. The precipitate is readily soluble in nitric acid, and in 
 ammonia, also in excess of free arsenic acid. In its general 
 deportment with reagents, it is very similar to the corresponding 
 precipitate produced from arsenious acid. 
 
 1. xoT grain of arsenic acid, in one grain of water, yields with 
 
 the reagent a copious, greenish-blue precipitate, which 
 after a time assumes a more distinctly green tint. Ten 
 grains of the solution yield a bluish-green precipitate, 
 which after a little time acquires a green color. 
 
 2. 1,000 grain : a good, bluish precipitate, destitute of a green 
 
 tint. The precipitate from ten grains of the solution has 
 a distinct greenish hue, which after a time becomes well 
 marked. 
 
REINSCH'S TEST. 315 
 
 This test, like the preceding, is much less satisfactory and 
 delicate, when applied to solutions of arsenic acid than to those 
 of arsenious acid. 
 
 3. Nitrate of Silver. 
 
 Nitrate of silver throws down from normal and neutral solu- 
 tions of arsenic acid, when not too dilute, a reddish-brown 
 precipitate of tribasic arsenate of silver (3 AgO ; AsOg). The 
 precipitate is readily soluble in nitric acid, but nearly wholly 
 insoluble in acetic acid; it is also freely soluble in ammonia, 
 and sparingly soluble in the carbonate and nitrate of ammonia. 
 !• To'o' grain of free arsenic acid, in one grain of water, yields 
 
 a quite copious precipitate, which aggregates into little 
 
 masses, with a tendency to crystallise. 
 
 2. 1,0 grain : a copious, reddish-brown precipitate. 
 
 3. 10,0 grain, yields a dirty-white precipitate, which after a 
 
 time assumes a reddish-brown tint. Ten grains of the 
 solution, yield a dirty reddish-brown precipitate, which 
 after a time acquires a clear reddish-brown color. 
 The production of a reddish-brown precipitate by this re- 
 agent, is quite peculiar to arsenic acid. 
 
 Ammonio-nitrate of silver produces, in solutions of arsenic 
 acid, much the same results as the silver-salt alone, as above 
 described. 
 
 4. Beinsch's Test. 
 
 When a solution of arsenic acid Or of an arsenate, is strongly 
 acidulated with hydrochloric acid and boiled with a slip of bright 
 copper-foil, metallic arsenic is slowly deposited upon the cop- 
 per, forming an iron-grey or steel-like coating, the appearance 
 depending on the thickness of the deposit. Without the addi- 
 tion of the hydrochloric acid, the metallic deposit fails to appear. 
 The arsenical nature of the deposit, may, of course, be shown 
 in the same manner as heretofore pointed out, in the considera- 
 tion of this test for the detection of arsenious acid. 
 !■ Too" grain of arsenic acid, in one grain of water, when 
 acidulated with hydrochloric acid, and heated to about the 
 boiling temperature with a mere fragment of copper-foil, 
 
316 ARSENIC ACID. 
 
 yields, after a time, a very good metallic deposit upon the 
 
 copper. 
 2. i.Joo grain: after a time, a quite good deposit. 
 3- r o.ooo grain, imparts only a slight tarnish to the copper, 
 
 even after prolonged heating, the evaporated liquid being 
 
 frequently renewed. 
 It will be observed, on comparing the above results with 
 those obtained from solutions of arsenious acid, that the metal 
 is much less completely separated by the test from solutions of 
 arsenic acid than from arsenious acid. 
 
 5. Sulphate of Magnesia and Ammonia. 
 
 This reagent may be prepared by precipitating a solution 
 of pure sulphate of magnesia by ammonia, and then adding 
 sufficient chloride of ammonium to redissolve the precipitate; 
 or, according to Fresenius, by dissolving one part of crystal- 
 lised sulphate of magnesia and one part of chloride of ammonium 
 in eight parts of water and four parts of solution of ammonia, 
 allowing the mixture to stand at rest for some days, and then 
 filtering. 
 
 Solutions of free arsenic acid, and of neutral arsenates, yield 
 with the reagent a white, crystalline precipitate of ammonio- 
 arsenate of magnesia, which contains twelve equivalents of 
 water of crystallisation, the formula being: 2MgO;NH4 0, 
 AsOs, 12 Aq. The pi-ecipitate is readily soluble in nitric, hydro- 
 chloric, and acetic acids, &lso in excess of free arsenic acid, 
 but only very sparingly soluble in ammonia, and in chloride of 
 ammonium. The reagent fails to produce a precipitate in solu- 
 tions of arsenious acid. 
 
 1. ToTT grain of arsenic acid, in one grain of water, yields a 
 
 copious, white, amorphous precipitate, which immediately 
 begins to crystallise, and in a little time becomes con- 
 verted into a mass of plumose crystals, Plate V, fig. 1. 
 
 2. i.Joo grain: no direct precipitate, but almost immediately 
 
 crystals begin to separate, and very soon there is a copious 
 deposit of crystals, having much the same forms as those 
 illustrated under 1. 
 
QUANTITATIVE ANALYSIS. 317 
 
 3- s7To"o grain: almost immediately, a granular cloudiness ap- 
 pears, followed in a littlq time by crystals; after several 
 minutes, there is a quite good, crystalline deposit. 
 4. To.ooo grain: in a very little time, a granular turbidity, and 
 after some minutes, a satisfactory precipitate, consisting 
 principally of small crystalline plates. 
 The reagent also produces a similar crystalline precipitate 
 in solutions of phosphoric acid. The true nature of the arsen- 
 ical crystals may be readily established by dissolving the pre- 
 cipitate in large excess of hydrochloric acid, and boiling the 
 solution with a slip of bright copper-foil, when the latter will 
 receive a coating of metallic arsenic. 
 
 Acetate of lead throws down from solutions of free arsenic 
 acid, and of alkaline arsenates, a white, curdy precipitate of 
 tribasic arsenate of lead (3PbO; AsOg). One grain of a lOOth" 
 solution of the acid yields a quite copious precipitate ; the same 
 quantity of a 1,000th solution yields a very good precipitate; 
 and a 10,000th solution becomes quite turbid. It need hardly 
 be remarked that this reagent also produces white precipitates 
 in solutions of most other acids. 
 
 Under the action of zinc and diluted sulphuric acid, in a 
 Marsh's apparatus, arsenic acid undergoes decomposition, with 
 the production of arsenuretted hydrogen, much in the same 
 manner as arsenious acid. 
 
 Solutions of arsenic acid, unlike those of arsenious acid,' fail 
 to reduce bichromate of potash; nor do they give rise to red 
 suboxide of copper, when boiled with caustic potash and sul- 
 phate of copper. 
 
 Quantitative Analysis. — Arsenic acid, when in solution, 
 may be estimated in the form of ammonio-arsenate of magnesia. 
 The solution is treated with excess of a clear mixture of sulphate 
 of magnesia, ammonia and chloride of ammonium, prepared 
 in the manner already described, and then allowed to stand in 
 a cool place for from twelve to twenty-four hours, in order that 
 the precipitate may completely separate. The precipitate is 
 then collected on a filter of known weight, washed with water 
 
318 ARSENIC ACID. 
 
 containing a little ammonia, dried at 212° as long as it loses in 
 weight, and its weight then noted. The dried precipitate, if 
 pure, will now consist of 2 MgO ; NH4 0, AsOs, Aq, and contain 
 60-53 per cent., by weight, of arsenic acid. 
 
 Arsenic acid may also be estimated by first reducing* it to 
 arsenious acid, by means of sulphurous acid gas, and then pre- 
 cipitating the metal as tersulphuret of arsenic, by sulphuretted 
 hydrogen. One hundred parts by weight of thoroughly dried 
 tersulphuret of arsenic, correspond to 93-5 parts of anhydrous 
 arsenic acid. 
 
MERCURY. 319 
 
 CHAPTER VI. 
 
 MERCURY. 
 
 Properties.-^— In its imcombined state, at ordinary tempera- 
 tures, mercury, or quicksilver, as it has been named, is a liquid 
 metal, having a silver-white color, high metallic luster, and a 
 density of 13"56 : it is the only metal that is fluid at ordinary 
 temperatures. At — 39° F. it solidifies to a crystalline, ductile 
 mass; and at about 660° it boils, being dissipated in the form 
 of a colorless, transparent vapory the specific gravity of which 
 is 6-976. Water has no action on the metal in its pure state. 
 Diluted nitric acid oxidises and dissolves it to nitrate of sub- 
 oxide of mercury ; the hot concentrated acid readily dissolves 
 it to nitrate of protoxide of mercury, with evolution of fumes 
 of binoxide of nitrogen. Hydrochloric acid has no action upon 
 it, but boiling sulphuric acid readily converts it into sulphate of 
 protoxide of the metal, with evolution of sulphurous acid gas. 
 
 Physiological Effects. — Many instances are reported in which 
 large quantities of mercury, even in some instances amounting 
 to some pounds, were taken into the body without producing 
 any deleterious effects. If, however, the metal, after being 
 swallowed, becomes oxidised, as is sometimes the case, it may 
 produce active symptoms. When inhaled in the form of vapor, 
 mercury may give rise to serious results, as has not unfre- 
 quently been witnessed in those engaged in mining the metal, 
 and others exposed to its fumes. 
 
 Combinations. — Mercury readily unites with most of the 
 metalloids. With oxygen it combines in two proportions, form- 
 ing the black, or suboxide of mercury (Hg20), and the protox- 
 ide, red oxide, or red precipitate (HgO). These oxides readily 
 unite with oxygen-acids, forming salts. The metal also unites 
 with sulphur in twO corresponding proportions : the subsulphuret 
 
320 MERCURY. 
 
 (HgaS) has a black color, so also has the protosulphuret (HgS) ; 
 by sublimation, the latter compound acquires a beautiful red 
 color, under which form .it is commonly known as vermilion. 
 The subiodide of the metal (Hg2l), has a dingy-green color, 
 while the protiodide (Hgl) has a brilliant, scarlet hue. The 
 compounds of mercury most frequently employed for medicinal 
 purposes, are the two chlorides, known at present as subchlo- 
 ride, or calomel (HgzCl), and protochloride, or corrosive subli- 
 mate (HgCl). 
 
 All the compounds of mercury are more or less poisonous ; 
 but of these, corrosive sublimate is one of the most active, and 
 in a medico-legal point of view, much the most important. 
 
 CoEEOsivE Sublimate. 
 
 Composition. — Corrosive sublimate consists of one chemical 
 equivalent of mercury combined with one of chlorine, and is, 
 therefore, the protochloride of mercury, its formula being HgCl. 
 Formerly, this compound was known as bichloride of mercury, 
 while calomel was considered the protochloride, whereas at 
 present calomel is regarded as a subchloride of the metal. This 
 change, in regard to the names of these compounds, is due to 
 the fact that formerly the combining equivalent of mercury was 
 believed to be 200, while at present 100 is considered its true 
 combining number. As met with in the shops, corrosive subli- 
 mate is usually either in the form of a white, amorphous pow- 
 der, or of semi-transparent crystalline masses ; but occasionally 
 it is found in the form of well-defined crystals. 
 
 Symptoms. — The effects of corrosive sublimate, when swal- 
 lowed in poisonous quantity, are a nauseous, metallic taste, with 
 a sense of heat and constriction in the mouth and throat ; nau- 
 sea, and pain in the stomach, attended with violent vomiting 
 and retching, the matters ejected being sometimes of a bilious 
 character and containing blood ; pain throughout the abdomen, 
 which generally becomes swollen and tender to the touch ; se- 
 vere purging, sometimes of bloody matters ; great anxiety ; 
 flushed countenance ; impaired or difficult respiration ; small, fre- 
 quent, and contracted pulse ; cold perspirations ; intense thirst ; 
 
PHYSIOLOGICAL EFFECTS. 321 
 
 scantiness or entire suppression of urine ; cramps in the ex- 
 tremities ; stupor, and sometimes death is ushered in with con- 
 vulsions. 
 
 Such are the symptoms usually produced by large doses 
 of this poison, but they are subject to considerable variation. 
 The vomiting and purging, as well as the pain in the stomach 
 and bowels, may cease for a time, and afterwards return with 
 increased violence. Instances are also reported in which purg- 
 ing and pain in the abdomen were even entirely wanting. In 
 some instances, on account of the local action of the poison, the 
 lining membrane of the mouth and the surface of the tongue, 
 present a white appearance. In protracted cases, inflammation 
 of the mouth and salivation usually supervene. 
 
 Among the more prominent differences usually observed be- 
 tween the symptoms of corrosive sublimate poisoning and those 
 occasioned by arsenious acid, Dr. Christison mentions the fol- 
 lowing : 1 . The symptoms of the former generally begin much 
 sooner, the irritation in the throat often manifesting itself during 
 the act of swallowing, and that in the stomach either immedi- 
 ately, or within a few minutes ; 2. Its taste is much more une- 
 quivocal and strong ; 3. The sense of acridity along the throat 
 and iiLthe stomach, is much more severe ; and 4. Blood is more 
 frequently discharged by vomiting and purging. 
 
 The following case, related by Devergie and quoted by Dr. 
 Christison, well illustrates the usual course of acute poisoning 
 by this substance. A woman swallowed three drachms of cor- 
 rosive sublimate, in solution. She was soon afterwards seized 
 with vomiting, purging, and pain in the abdomen. In five 
 hours, the skin was cold and clammy, the limbs relaxed, the 
 face pale, eyes dull, and the expression that of horror and anx- 
 iety. The lips and tongue v\-ere white and shriveled, and there 
 were violent fits of pain and spasm in the throat whenever an 
 attempt was made to swallow liquids ; also burning and prick- 
 ing along the gullet ; frequent, vomiting of mucus and bilious 
 matters, with burning pain in the stomach and tenderness of 
 the epigastrium on the slightest pressure ; and profuse purging, 
 with tenesmus. The pulse was almost imperceptible, and the 
 breathing much retarded. In eighteen hours, these symptoms 
 
 21 
 
322 MERCURY. 
 
 still continued without any material change ; but the limbs were 
 then insensible; In twenty-three hours, the patient died in a 
 fit of fainting, the mind having remained clear up to the time 
 of death. 
 
 In a very protracted case, reported by Dr. Vigla, the fol- 
 lowing symptoms were observed. A man, aged twenty-seven 
 years, swallowed, in a state of solution, about fifty grains of 
 corrosive sublimate. At once there occurred a strong metallic 
 taste, constriction of the throat, nausea, and vomiting ; but no 
 severe pain. The vomited matters at first Consisted of food, 
 then of a serous fluid. An emetic was administered, and after- 
 wards milk and white of egg. On the following day, there was 
 more intense pain and irritation of the throat, coming on in 
 paroxysms ; convulsive cough, expectoration of bloody mucus, 
 and much sufi'ering. Enteritis also developed itself, with vio- 
 lent colic, tenesmus, and frequent slimy and bloody evacuations. 
 On the third day, there was great inflammation of the mucous 
 membrane of the . throat and mouth, oedema of the palate and 
 gullet ; pseudo-membranous separation from the inflamed parts, 
 and salivation ; the intelligence was somewhat restored. The 
 pulse was eighty-six ; the urine normal. Up to the twelfth day, 
 all inflammatory symptoms gradually subsided; but from that 
 time great prostration of the powers of life and mercurial ca- 
 chexia were presented. On the fifteenth day, ecchymosis upon 
 the skin, irregular action of the heart, hiccough, albuminuria, 
 and great irritability of the whole body were present. The 
 man died on the sixteenth day without any convulsion or strug- 
 gle, in a state of extreme exhaustion. (Brit, and For. Med.- 
 Chir. Rev., October, 1860, p. 380.) 
 
 In poisoning by frequently repeated small doses of corrosive 
 sublimate, or chronic poisoning, as it is termed, the foUowing 
 symptoms are usually observed : a coppery taste in the mouth, 
 loss of appetite, offensive breath, tenderness of the gums, pains 
 in the stomach and bowels, nausea, inflammation and ulceration 
 of the salivary glands, sweUing of the tongue, increased flow of 
 saliva, hot skin, quick pulse, and great muscular debility. It 
 is weU known that some persons are much more susceptible than 
 others to the action of mercurial compounds. In a case cited 
 
FATAL PERIOD. 323 
 
 by Dr. Christison, two grains of calomel caused ptyalism, ex- 
 tensive ulceration of the throat, exfoliation of the lower jaw, 
 and death. 
 
 The external application of corrosive sublimate has not un- 
 frequently been followed by fatal results. Two children, aged 
 seven and eleven years respectively, had an ointment composed 
 of one part of corrosive sublimate to four parts of tallow rubbed 
 over the scalp, for the cure of scaled head. Extreme suffering 
 almost immediately ensued, and in forty minutes they were 
 completely delirious. There was excessive vomiting, great pain 
 in the bowels, with purging and bloody stools, and in one 
 instance, complete suppression of urine : there was no ptyalism. 
 Death ensued in one instance on the seventh, and in the other, 
 on the ninth day. (Wharton and Stilld, Med. Jur., p. 535.) 
 In an instance quoted by Orfila, the application of powdered 
 corrosive sublimate to the breast of a woman affected with an 
 ulcerated cancer, caused intense pain in the part, nausea, bloody 
 vomiting, convulsions, and death on the follo\ying morning. 
 
 Period when Fatal. — The fatal period, in acute poisoning by 
 corrosive sublimate, is subject to considerable variation; but on 
 an average, perhaps, death takes place in about twenty-four 
 hours. In an instance in which three children were accident- 
 ally poisoned by this substance, dispensed by mistake for calo- 
 mel, the eldest, &,ged seven years, took eighteen grains, and 
 died in three hours ; the youngest, aged about two years, took 
 six grains, and died in eleven hours; while the second, aged 
 three years, received twelve grains, and apparently recovered 
 from the immediate effects of the poison, but died with second- 
 ary symptoms on the twenty-third day. (Medico-Chirurgical 
 Eeview, April, 1835.) In a case recorded by Dr. Taylor (On 
 Poisons, p. 462), a man died from the effects of an unknown 
 quantity of the poison, in less than half an hour. This is the 
 most rapidly fatal case yet reported. 
 
 In regard to protracted liases. Dr. Beck cites an instance in 
 which death did not occur until the eighth day ; and another in 
 which a man took about six or eight grains of the poison, and 
 life was prolonged until the twelfth day. (Med. Jur., vol. ii, 
 p. 620.) In a case reported by Dr. Coale, death took place 
 
324 MERCURY. 
 
 on the eleventh day ; and in another, by Dr. Jackson, on the 
 thirteenth day. (Wharton and StOle, Med. Jur., p. 534.) In 
 Dr. Vigla's case, already cited, death was delayed until the 
 sixteenth day. 
 
 Fatal Quantity. — That the same effects are not always pro- 
 duced by equal quantities of corrosive sublimate, is well illus- 
 trated in the cases of the three children just cited, in one of 
 whom, six grains of the poison caused death in eleven hours, 
 whilst in another, twelve grains did not prove fatal until the 
 twenty-third day. In Dr. Coale's case, ten grains of the poison, 
 dispensed by mistake for calomel, "were mixed and partially 
 swallowed, but the great distress it caused produced ejection of 
 much of it from the stomach." (Amer. Jour. Med. Sci., Jan., 
 1851, p. 47.) This case is also remarkable in that during the 
 eleven days the man survived after taking the dose, there was 
 entire suppression of urine. A case has also just been cited in 
 which six or eight grains proved fatal to an adult. 
 
 On the other hand, several instances are reported in which 
 persons recovered after having taken from half a drachm to two 
 drachms of the poison ; and Dr. Beck quotes an instance in 
 which recovery took place after six drachmsj in solution, had 
 been swallowed. The writer just mentioned, also cites a case, 
 reported by Dr. Budd, in which a female took an ounce of the 
 poison, and after suffering the usual severe symptoms, entirely 
 recovered. So, also. Dr. Taylor cites an instance, mentioned 
 by Dr. Booth, in which recovery followed after a similar quan- 
 tity had been taken. It is but proper to add, that in most, if 
 not all, these cases of recovery, there was early vomiting. 
 
 Treatment. — Of the various antidotes that have been pro- 
 posed, in poisoning by corrosive sublimate, albumen, in the form 
 of white of egg, seems to be much the most efficient. Orfila, 
 who first suggested this antidote, employed it with complete 
 success in experiments on poisoned animals ; and it has in sev- 
 eral instances been, at least apparently, the means of saving 
 life in the human subject. It should be given in large quan- 
 tity, and its administration speedily followed, if necessary, by 
 the exhibition of an emetic. According to Dr. Peschier, the 
 white of one egg is required to neutralise four grains of the 
 
POST-MORTEM APPEARANCES. 325 
 
 poison. Dr. Taddei strongly advised, as an antidote, the use 
 of wheat flour, or gluten. This remedy also has been success- 
 fully administered to animals, and has been resorted to with 
 apparent success in the human subject. The free exhibition of 
 milk has also been highly recommended. 
 
 Dr. Buckler, of Baltimore, in 1842, proposed the use of a 
 mixture of gold-dust and iron-filings, and adduced some experi- 
 ments on animals in support of its efficacy ; but these results 
 were not confirmed by the experiments of Orfila (Toxicologic, 
 vol. i, p. 687). More recently. Dr. C. Johnston, of Baltimore, 
 exhibited this mixture to a gentleman who had swallowed eighty 
 grains of corrosive sublimate, and the patient recovered. (Amer. 
 Jour. Med. Sci., April, 1863, p. 340.) Since, however, in this 
 case, previous to the administration of the gold mixture, which 
 was not exhibited until about twenty-five minutes after the poi- 
 son had been taken, there had been violent and almost inces- 
 sant vomiting for about fifteen minutes, and a mixture of white 
 of egg and milk had been freely given, it is by no means cer- 
 tain that the alleged antidote had any part whatever in the 
 recovery of the patient. 
 
 Among the other antidotes that have been advised for this 
 poison, may be mentioned the protochloride of tin, iron filings 
 either alone or mixed with zinc, the hydrated sulphurets of iron, 
 the carbonates of the alkalies, and meconic acid and its soluble 
 salts. Neither of these substances, however, possesses any ad- 
 vantage over those mentioned above, and in fact some of them 
 seem to be entirely inert ; moreover, neither of them is as likely 
 to be at hand as either white of 6gg, flour, or milk. 
 
 POST-MOETEM APPEARANCES. — The lining membrane of the 
 mouth, fauces, and oesophagus is frequently more or less inflamed 
 and softened; but cases are reported in which these parts were 
 found in a perfectly normal condition. The action of this poi- 
 son upon the stomach and bowels is generally much greater 
 than that usually caused by arsenic. The coats of the stomach 
 are often more or less corroded and softened; and its internal 
 surface has presented a dark, ulcerated appearance. In a case 
 cited by Dr. Christison, in which the patient survived thirty- 
 one hours, the coats of the stomach were perforated. The 
 
326 MERCURY. 
 
 intestines, especially the colon and rectum, often present signs of 
 violent inflammatory action. This condition has been observed 
 in cases in which the stomach was found but little affected. 
 The urinary organs also are often much inflamed, and the blad- 
 der greatly contracted and nearly or altogether empty. An 
 instance is related in which the bladder was reduced to the size 
 of a walnut ; and another, that of a child, in which this organ 
 was no larger than a marble. 
 
 In the two cases of the three children, already mentioned, 
 that proved fatal in three and eleven hours respectively, the 
 mucous membrane of the mouth, pharynx, and oesophagus was 
 found, in several places, softened, white, and could be easily 
 detached by the handle of the scalpel. The mucous surface of 
 the stomach and bowels exhibited patches of acute inflamma- 
 tion, and here and there of partial erosion ; at these places, its 
 color was of a deep brown, or of an eschar-like hue. On the 
 inner surface of the left ventricle of the heart, in the elder 
 child, there were observed two patches of distinct ecchymosis, 
 caused by the effusion of blood between the investing serous 
 membrane and the muscular tissue. In the younger child, also, 
 a similar appearance, but less distinctly marked, was found. 
 No other appearances are mentioned in the description of these 
 cases. 
 
 In a case related by Dr. H. Williams (Am. Jour. Med. Sci., 
 Jan., 1851, p. 79), in which thirty grains of the poison proved 
 fatal, to an adult, on the third day, the following appearances 
 were observed, twenty-five hours after death. The stomach 
 was contracted, for the extent of about two inches, at its mid- 
 dle portion, into the form of a dumb-bell. It contained a .small 
 quantity of bright yellow fluid, having the consistency o? thin 
 gruel. Its larger and smaller curvatures presented patches of 
 dotted injection, of a bright crimson tint ; and the mucous 
 membrane was a little softened in the neighborhood of the most 
 vivid red patches. Patches of beautifully arborescent vascu- 
 larity were also observed at intervals along the whole extent of 
 the small intestines ; the large intestines were healthy. The 
 bladder was contracted, and contained about a drachm of turbid 
 urine. The other organs of the body were healthy. 
 
CHEMICAL PROPERTIES. 327 
 
 Chemical Peoperties. 
 
 GrENEEAL Chemical Natdee. — Corrosive sublimate crystal- 
 lises, without water of crystallisation, in the form of colorless, 
 transparent, rhombic prisms. Its specific gravity has been vari- 
 ously stated at from 5'2 to 6"5. It has an exceedingly styptic, 
 nauseous, metallic, and persistent taste. When heated to a 
 temperature of 509° F., it fuses to a colorless liquid, which' boils 
 at about 563°, evolving an extremely acrid and poisonous vapor. 
 If the vapor be received upon a cold surface, it frequently con- 
 denses in the form of white crystalline needles. 
 
 Corrosive sublimate is readily decomposed by the fixed alka- 
 lies, forming a chloride of the alkali and oxide of mercury. 
 Cold sulphuric acid fails to decompose or dissolve it, but it is 
 somewhat soluble, without decomposition, in nitric and hydro- 
 chloric acids. When in aqueous solution, it is readily decom- 
 posed and precipitated by various vegetable and animal prin- 
 ciples, such as albumen, fibrin, casein, gluten, and tannic acid. 
 Hence the utility of these substances, as antidotes, in poisoning 
 'by this salt. 
 
 Solubility. 1. In Water. — The solubility of corrosive subli- 
 mate in water, at the ordinary temperature, has been variously 
 stated at from nine to twenty parts of the fluid. According to 
 our own experiments, when the pure, powdered crystallised salt 
 is digested with ten times its weight of pure distilled water at a 
 temperature of about 60°, with occasional agitation, for twenty- 
 four hours, the solution then filtered, and the filtrate cautiously 
 evaporated to dryness, it leaves a residue indicating that one 
 part of the salt had dissolved in 13'30 times its weight of the 
 liquid. 
 
 According to most observers, the salt is soluble in less than 
 three times its weight of boiling water. From these statements, 
 it is obvious that the quantity of the poison that may be taken 
 up in solution by water, wiU in a great measure depend upon 
 the temperature of the latter. 
 
 2. In Alcohol. — When the powdered salt is agitated for some 
 minutes, at the ordinary temperature, with two parts of alcohol 
 
328 MERCURY. 
 
 of specific gravity 0800 (=98 per cent.), tlie solution filtered, 
 and evaporated to dryness, the residue indicates that one part 
 of the poison had dissolved in 2-47 parts of the liquid. 
 
 On digesting the powdered salt with five parts of common 
 tvhisJci/, for twenty-four hours, at the ordinary temperature, with 
 frequent agitation, one part of the former required fifteen parts 
 of the latter for solution. 
 
 3. In Absolute Ether. — When powdered corrosive sublimate 
 is digested, with frequent agitation, for twenty-four hours, with 
 five parts of absolute ether, at a temperature of about 60°, one 
 part of the salt dissolves in 8'8 parts of the menstruum. The 
 salt is much more freely soluble in ordinary commercial ether, 
 this liquid usually taking up about one-third of its weight of 
 the poison. 
 
 By taking advantage of the solubility of corrosive sublimate 
 in ether, the salt may be separated from its aqueous solution, 
 or from organic mixtures. If one grain of the mercury com- 
 pound be dissolved in one hundred grains of pure water, and 
 the solution agitated for several minutes with an equal volume 
 of commercial ether, the latter withdraws from the water 0'67 
 of a grain of the salt. According to M. Karls, the presence of 
 camphor very much increases the solvent power of both ether 
 and alcohol for corrosive sublimate. 
 
 4. In Chloroform. — Corrosive sublimate is only very spar- 
 ingly soluble in chloroform. When the powdered salt is occa- 
 sionally agitated during twenty-four hours with twenty parts of 
 this liquid, at the ordinary temperature, one part of the salt 
 requires seventeen hundred parts of the fluid for solution. 
 
 Of Solid Corrosive Sublimate. 
 
 In its solid state, corrosive sublimate may be identified by a 
 variety of reactions. 
 
 1 . When a small portion of the salt is moistened with a drop 
 of a solution of iodide of potassium, it assumes a bright scarlet 
 color, due to the formation of iodide of mercury, which is sol- 
 uble to a colorless solution in excess of the potassium com- 
 poimd. This reaction is extremely delicate, and peculiar to the 
 
REACTIONS OF CORROSIVE SUBLIMATE. 329 
 
 proto-combinations of mercury. The residue obtained from the 
 evaporation of one grain of water containing the 1,000th part of 
 a grain of corrosive sublimate, when moistened with the reagent, 
 acquires a fine scarlet color ; the residue from the 10,000th of 
 a grain, assumes a distinct yellow hue, and soon dissolves. 
 
 2. If a drop of a strong solution of iodide of potassium be 
 placed on a piece of bright copper, and a small quantity of cor- 
 rosive sublimate added, the latter undergoes decomposition and 
 the copper becomes stained with a deposit of metallic mercury, 
 which when rubbed with a soft substance, as the end of the 
 finger, assumes a bright silvery appearance. This reaction will 
 manifest itself with the least visible quantity of the mercurial 
 compound. The dried stain is readily dissipated by heat. If, 
 in this experiment, the iodide of potassium solution be substi- 
 tuted by a drop of hydrochloric acid, the same metallic deposit 
 takes place, and the reaction is equally delicate. 
 
 3. When corrosive sublimate is moistened with a few drops 
 of a solution of protochloride of tin, it slowly assumes a grey 
 color, and finally becomes nearly black, from the separation of 
 metallic mercury. In this reaction, the mercurial compound 
 yields up the whole of its chlorine to the tin, converting the 
 latter into bichloride of tin. 
 
 4. If the salt be treated with a few drops of a solution of 
 sulphuret of ammonium, it quickly acquires a yellow color, which 
 in a little time changes to black, due to the formation of sul- 
 phuret of mercury. This transition of color is peculiar to proto- 
 combinations of mercury. 
 
 5. When touched with a strong solution of caustic potasli or 
 of soda, it immediately assumes a yellow or brownish-yellow 
 color, due to the production of protoxide of mercury. This 
 reaction serves to distinguish corrosive sublimate from calomel, 
 which is blackened by the reagent, due to the formation of 
 sub-oxide of mercury. Calomel is also blackened by caustic 
 ammonia, whereas the color of corrosive sublimate remains un- 
 changed. 
 
 6. When a small quantity of corrosive sublimate is heated 
 in a reduction-tube, it volatilises unchanged, and recondenses 
 in the cooler portion of the tube, usually in the form of groups 
 
330 MERCURY. 
 
 of crystals of the forms illustrated in Plate V, fig. 2. The ex- 
 act forms of these crystals, however, will depend in a great 
 measure upon the quantity of the salt employed : the most per- 
 fect crystals are obtained by using only a very minute portion 
 of the salt ; when a comparatively large quantity is employed, 
 the sublimate is in the form of a dense crystalline mass, desti- 
 tute of any distinct crystals. 
 
 In applying this test, the analyst should bear in mind that 
 salts of ammonia, oxalic acid, and arsenious acid, will also, like 
 corrosive sublimate and certain other compounds of mercury, 
 completely volatilise with the production of a white sublimate. 
 The sublimate from arsenious acid, however, is in the form of 
 octahedral crystals, whereas that from corrosive .sublimate is 
 never in the octahedral form ; moreover, the former substance 
 does not fuse before volatilising. The sublimates from oxalic 
 acid and salts of ammonia, may closely resemble that from the 
 mercurial compound, but the latter is readily distinguished from 
 these, as well as from all other volatile white powders, in that 
 when touched with a solution of iodide of potassium, it assumes 
 a bright scarlet color. 
 
 7. When a small quantity of perfectly dry corrosive subli- 
 mate is intimately mixed with several times its volume of 
 recently ignited carbonate of soda, and the mixture heated in a 
 reduction-tube, the heat being very gradually increased, it yields 
 a globular sublimate of metallic mercury ; at the same time, an 
 equivalent quantity of chloride of sodium is formed and remains 
 in the residue. The reaction, in this case, is expressed as fol- 
 lows : HgCl + NaO, C02 = NaCl + Hg + + C02. This reaction 
 will manifest itself with the least visible quantity of the corro- 
 sive salt, at least if the operation be conducted in a very narrow 
 or contracted tube ; it must be remembered, however, that the 
 production of the metallic sublimate is common to all the com- 
 pounds of mercury. 
 
 When the sublimate thus obtained is examined under a low 
 power of the microscope, it will be found to consist of minute, 
 opake, spherical globules, which under incident light have an 
 exceedingly brilliant, metallic luster. These characters read- 
 Uy distinguish the mercurial from all other sublimates. The 
 
AMMONIA TEST. 331 
 
 presence of the chlorine in the chloride of sodium, resulting from 
 the decomposition of the corrosive sublimate, may be shown, by 
 dissolving the saline residue in a little warm water, acidulating 
 the solution with nitric acid, and then adding a little nitrate of 
 silver, when the chlorine wiU be thrown down as white chloride 
 of silver, which is insoluble in nitric acid but readily soluble in 
 ammonia. Similar results would be obtained if the substance 
 submitted to examination was calomel; but the insolubility of 
 the latter in water, readily distinguishes it from corrosive sub- 
 limate. Before resorting to this method of reduction, in the 
 examination of a suspected substance, the operator should sat- 
 isfy himself that the carbonate of soda about to be employed, 
 is perfectly free from chlorine. 
 
 Of Solutions of Coreosive Sublimate. 
 
 Pure aqueous solutions of corrosive sublimate are colorless, 
 and when not very dilute, feebly redden litmus-paper. The 
 nauseous metallic taste of the salt is well marked, even in very 
 highly diluted solutions. On cooling, hot concentrated solutions 
 throw down the excess of the salt in its crystalline state. When 
 a drop of a tolerably strong solution is allowed to evaporate 
 spontaneously, the residue usually consists of long, transparent, 
 crystalline needles and prisms ; but from more dilute solutions, 
 it is usually in the form of a confused crystalline film. The 
 crystallisation of the salt is readily interfered with by the pres- 
 ence of organic matter. 
 
 In the following investigations, in regard to the chemical 
 behavior of solutions of corrosive sublimate, pure aqueous solu- 
 tions of the salt were employed, i The fractions indicate the 
 fractional part of a grain of the anhydrous salt present in one 
 grain of the liquid; and the results, unless otherwise stated, 
 refer to the behavior of one grain of the solution. 
 
 1. Ammonia. 
 
 Aqua ammonia produces in solutions of corrosive sublimate, 
 a white, flocculent precipitate of the double chloride and amide 
 
332 MERCURY. 
 
 of mercury (HgCl, HgNH2). The precipitate is soluble in large 
 excess of the precipitant, and readily soluble in the mineral 
 acids ; it is also soluble in some of the salts of ammonia, but 
 insoluble in chloride of ammonium. 
 
 1. j-J-g" grain of corrosive sublimate, in dne grain of water, 
 
 yields with the reagent, a very abundant precipitate. If 
 the mercurial solution be exposed to the vapor of ammo- 
 nia, it yields the same reaction. 
 
 2. TTTo'o grain, yields a quite good deposit. 
 
 3- 57o"o"o grain, yields a quite satisfactory reaction, by either 
 
 ammonia or its vapor. 
 
 4- To","'o"o"o grain : a quite perceptible turbidity. 
 
 This reagent also produces white precipitates in solutions of 
 various other substances, beside proto-combinations of mercury. 
 But if the mercurial precipitate be dried and heated, it readily 
 volatilises without residue, in which respect it differs from all 
 other metallic precipitates produced by the reagent. When 
 heated with a solution of caustic potash, the precipitate is de- 
 composed, with the production of yellow oxide of mercury. 
 The precipitate is also decomposed by protochloride of tin, with 
 the separation of metallic mercury. 
 
 2. Potash and Soda. 
 
 The fixed caustic alkalies, when added in not sufficient 
 quantity to effect complete decomposition, throw down from 
 quite strong solutions of corrosive sublimate, reddish-brown 
 amoi'phous precipitates, consisting of a compound of protoxide 
 of mercury and the undecomposed chloride of the metal ; but 
 when the reagent is added in excess, the precipitate has a yel- 
 low color, and consists alone of the protoxide of mercury. The 
 precipitate is insoluble in excess of the precipitant, but readily 
 soluble in free acids. 
 !• Too^ grain of corrosive sublimate, yields a rather copious, 
 
 reddish-brown or yellow deposit. 
 2. T oT grain, yields only a slight cloudiness. 
 
 The production of a reddish-brown precipitate, which be- 
 comes yellow upon the further addition of the alkaline reagent, 
 
IODIDE. OF POTASSIUM TEST. 333 
 
 is peculiar to the per-corabinations of mercury. The only other 
 metals that yield yellow precipitates with the reagent, are the 
 rare substances platinum and uranium : the precipitate from the 
 former of these is usually in the form of octahedral crystals ; 
 but the precipitate from the latter, like that from mercurial 
 compounds, is amorphous and insoluble, in excess of the pre- 
 cipitant. 
 
 When the precipitated protoxide of mercury is collected, 
 dried, and strongly heated in a reduction-tube, it undergoes 
 decomposition, with the evolution of free oxygen gas and the 
 production of a globular sublimate of metallic mercury. This 
 reaction wiU serve for the identification of the merest trace of 
 the mercurial precipitate. The presence of the chlorine of the 
 corrosive subhmate, in the liquid from which the mercury was 
 precipitated, may be shown, by acidulating the solution with 
 nitric acid, and then adding nitrate of silver, when it wiU yield 
 a white precipitate of chloride of silver. 
 
 The protocarbonates of the fixed alkalies, when added in lim- 
 ited quantity, throw down from one grain of a 100th solution of 
 corrosive sublimate, a quite good, yellowish precipitate ; when 
 an excess of the reagent is employed, the precipitate has a 
 brick-red color. A similar quantity of a 500th solution of the 
 salt, yields only a slight turbidity. 
 
 3. Iodide of Potassium. 
 
 This reagent produces in solutions of corrosive subhmate, 
 a bright scarlet, amorphous precipitate of iodide of mercury 
 (Hgl), which is readily soluble in excess of the precipitant, as 
 well as in large excess of the mercurial solution. At first, the 
 precipitate has frequently a yellow color, but it quickly becomes 
 scarlet, except if only in minute quantity, when the yellow color 
 may be permanent. The iodide of mercury is also soluble in 
 the alkaline chlorides, and in alcohol, but only slowly soluble in 
 the diluted mineral acids ; strong nitric and sulphuric acids 
 readily decompose it,- with the elimination of iodine. 
 
 1, Y^ grain of the salt, yields a copious, scarlet precipitate. 
 
 2. r.wo grain : a reddish-yellow deposit. 
 
334 MERCURY. 
 
 3- 2,500 grain, yields, with a very minute quantity of the re- 
 agent, a quite satisfactory, yellow precipitate. 
 The production of a scarlet precipitate by this reagent, is 
 peculiar to solutions of persalts of mercury. The iodide of 
 mercury, when washed, dried, and heated in a reduction-tube, 
 volatilises unchanged, and recondenses in the form of a yellow, 
 partly crystalline sublimate, the color of which slowly changes 
 to scarlet. When the dried precipitate is intimately mixed 
 with recently ignited carbonate of soda and heated in a reduc- 
 tion-tube, it yields a sublimate of metallic mercury. 
 
 4. Sulphuretted Hydrogen. 
 
 When somewhat concentrated neutral or acidulated solutions 
 of corrosive subhmate are treated with a relatively small quan- 
 tity of sulphuretted hydrogen gas or of sulphuret of ammonium, 
 they yield a precipitate, which, at least when the mixture is 
 agitated, has a pure white color, and consists of the -protosul- 
 phuret of mercury and undecomposed corrosive sublimate. On 
 the further addition of the reagent, the precipitate acquires a 
 yellow, then a brown color, and finally becomes ilach, when it 
 consists alone of the sulphuret of mercury. From more dilute 
 solutions, the precipitate has at first a brownish color. 
 
 The precipitated sulphuret of mercury is insoluble in nitric 
 and hydrochloric acids, even on the application of heat ; but it 
 is readily decomposed and dissolved by cold nitro-hydrochloric 
 acid, with the separation of free sulphur, and the formation of 
 protochloride of mercury and more or less sulphate of mercury, 
 the latter compound being derived from the oxidation of some 
 of the sulphur. It is insoluble in the caustic alkalies, and in 
 the alkaline sulphurets. 
 
 The following results, in regard to the reactions of this 
 test, refer to the behavior of ten grains of the corrosive sub- 
 limate solution, when acidulated with hydrochloric acid and 
 subjected to the action of a slow stream of the washed sul- 
 phuretted gas. 
 
 1. 100th solution (= iV grain of HgCl), yields an immediate, 
 brownish precipitate, which soon assumes a dark brown 
 
SULPHURETTED HYDROGEN TEST. 335 
 
 color, and ultimately becomes black, the final precipitate 
 being quite copious. 
 
 2. 1,000th solution, yields a yellowish-brown, brown, then a 
 
 rather copious, black precipitate. 
 
 3. 10,000th solution : the liquid immediately assumes a brown- 
 
 ish color, then small brownish flakes separate, and after a 
 Kttle time, there is a good, brownish deposit. 
 i. 25,000th solution : almost immediately the liquid assumes a 
 yellowish color, and in a few minutes, very small, brown- 
 ish flakes appear, which after some time subside to a very 
 distinct deposit. 
 
 5. 50,000th solution : very soon the fluid becomes turbid, and 
 
 after standing some time, throws down a just perceptible, 
 yellowish precipitate. 
 
 6. 100,000th solution, when saturated with the gas and allowed 
 
 to stand several hours, undergoes no well-marked change. 
 
 The progressive change of color from white to black, of the 
 precipitate produced by this reagent, is peculiar to solutions of 
 persalts of mercury. But this change, as shown above, is weU 
 marked only in comparatively strong solutions of the mercurial 
 salt ; and, the production of a black or brownish precipitate is 
 not in itself characteristic of mercury, .since there are several 
 other metals that yield similar results, even from acidulated 
 solutions. 
 
 The sulphuret of mercury differs from all other black precip- 
 itates, produced under like conditions, in that when thoroughly 
 dried, and heated in a reduction-tube, it completely volatilises, 
 without residue or decomposition, and yields a black sublimate, 
 having a metallic appearance. Again, when mixed with anhy- 
 drous carbonate of soda, and heated in a reduction-tube, it 
 undergoes decomposition with the production of a globular sub- 
 limate of metallic mercury. Either of these methods, but the 
 latter is preferable, will serve for the identification of very 
 minute traces of the mercurial compound. 
 
 If the hquid from which the mercury was precipitated by 
 the sulphur reagent, was not purposely acidulated with hy- 
 drochloric acid, previous to the application of the reagent, it 
 will serve for the detection of the chlorine of the corrosive 
 
336 MERCURY. 
 
 sublimate, which element now exists as free hydrochloric acid. 
 For this purpose, the filtered liquid is gently heated until the 
 odor of the sulphuretted hydrogen has entirely disappeared, and 
 then treated with a solution of nitrate of silver. 
 
 5. Chloride of Tin. 
 
 When a limited quantity of protochloride of tin is added to 
 solutions of corrosive sublimate, the latter, giving up a portion 
 of its chlorine to the tin, is reduced to subchloride of mercury, 
 or calomel, which falls as a white precipitate, the reaction being : 
 2 HgCl + SnCl = SnClj + HgaCl. In the presence of an excess 
 of the reagent, the mercury is entirely deprived of its chlorine 
 and separates as a dark grey precipitate of exceedingly minute 
 globules of the metal. The reaction in this case is : HgCl + 
 SnCl = SnClz + Hg. The separation and subsidence of the me- 
 tallic precipitate is much facilitated by heating the mixture with 
 a little hydrochloric acid; if the clear supernatant liquid be 
 then decanted, and the residue again heated with a little fresh 
 hydrochloric acid, the finely divided mercury wiU unite into 
 larger globules : the hydrochloric acid employed in this opera- 
 tion, should be perfectly free from nitric acid; otherwise, the 
 metallic globules may disappear, being dissolved. This test 
 may be conveniently applied in a watch-glass. 
 1- Tou grain of corrosive sublimate, in one grain of water, 
 yields with the reagent a rather copious precipitate, which 
 at first is white, but quickly changes to a grey color, and 
 then becomes almost black. 
 2. 1,000 grain, yields much the same results as 1. 
 3- 5Too"o grain : a quite good precipitate. 
 4. T o.oou grain, yields a quite distinct reaction. 
 
 The production of metallic globules by this test, is, of course, 
 peculiar to solutions of mercury. When the precipitate is pres- 
 ent in only minute quantity, its globular nature may still be 
 readily recognised by means of a hand-lens or a low power of 
 the microscope. If the precipitate be stirred with a small piece 
 of bright copper-foil, the latter receives a coating of metallic 
 mercury, which when rubbed by a soft body, assumes a bright 
 
COPPER TEST. 337 
 
 silvery appearance. In this manner, especially by the aid of a 
 drop of hydrochloric acid and a gentle heat, the true natiu'e of 
 a mercurial deposit that will not furnish satisfactory globules, 
 may sometimes be readily determined. 
 
 It is important to bear in mind, in the application of this 
 test, that the reaction of protochloride of tin is interfered with 
 or entirely prevented, by the presence of alkaline chlorates, 
 and also of free nitric acid. 
 
 6. Copper Test. 
 
 When a small slip of bright copper-foil is placed in a normal 
 solution of corrosive sublimate, the latter is decomposed with 
 the deposition of metallic mercury upon the copper. The deli- 
 cacy of this reaction is much increased by acidulating the solu- 
 tion with hydrochloric acid, and also by heat. The deposited 
 mercury, when separated from normal solutions of the salt, has 
 usually a dark grey color; whilst, when from acidulated solu- 
 tions, it has generally a bright silvery appearance : its exact 
 appearance, however, will depend much upon the thickness of 
 the deposit, which in its turn, will, of course, depend upon the 
 strength of the solution and the size of the copper-foil employed. 
 When the deposit has a dull color, it immediately acquires a 
 bright, mirror-Kke appearance, on being rubbed with a piece of 
 soft wood or any similar substance. 
 
 The same metallic deposit will, of course, make its appear- 
 ance, when a drop of the mercury solution is placed on a piece 
 of bright copper plate. Under these circumstances, it has been 
 proposed to touch the copper, through the mercurial solution, 
 with a needle of zinc. This somewhat facilitates the decom- 
 position of the mercurial compound, but at the same time, it 
 causes the separated mercury to be distributed over a greater 
 surface, part of it being deposited upon the immersed end of 
 the zinc. 
 
 When a small piece of the coated copper-foil is carefully 
 washed, dried at a moderate temperature, in a water-bath, and 
 heated in a narrow, perfectly dry reduction-tube, the mercury 
 volatilises and recondenses in the cooler portion of the tube, 
 
 22 
 
338 MERCURY. 
 
 forming a mist-like sublimate. Under a low power of the mi- 
 croscope, this sublimate will be found to consist of innumerable 
 spherical globules, which are opake to transmitted light, and 
 present a bright silvery appearance, when viewed under inci- 
 dent light. These characters readily distinguish the mercurial 
 from all other sublimates. 
 
 In the following investigations, in regard to the limit of this 
 test, one grain of the mercurial solution, placed in a thin watch- 
 glass, was acidulated with hydrochloric acid, and the mixture 
 heated with a small fragment of the copper-foil. 
 
 1. You grain of corrosive sublimate, imparts to the copper an 
 
 immediate luster, and very soon the deposit becomes com- 
 paratively thick. This reaction takes place about equally 
 well without the presence of the free acid or the aid of 
 heat. The copper employed should measure about \\h. by 
 Xoth of an inch in extent. When the washed and dried 
 coated copper is heated in a narrow reduction-tube, it 
 yields a very good, globular sublimate, many of the glob- 
 ules measuring the 100th of an inch in diameter. 
 
 2. 1,0^0 grain : when the copper employed measures about -g-th 
 
 by iVth of an inch, in extent, it immediately assumes a 
 silvery appearance, and in a little time, receives a grey 
 coating. Similar results are obtained without the aid of 
 heat. Without either the free acid or heat, the deposit 
 begins to form in a very little time ; by heat alone, im- 
 mediately. The coated copper, when heated in a small 
 reduction-tube, yields a very satisfactory globular sub- 
 limate. 
 
 3. 10,0 grain : when the acidulated liquid is heated with a 
 
 slip of copper measuring about xVth by aVth of an inch 
 in extent, the mercurial deposit manifests itself immedi- 
 ately, and very soon becomes satisfactory. If the coated 
 copper be heated in a very narrow reduction-tube, it yields 
 a sublimate which is quite perceptible to the naked eye, 
 and which, under the microscope, is found to consist of 
 innumerable spherical globules. 
 When deposits but little smaller than that just considered, 
 are heated in a reduction-tube of the ordinary form, even of 
 
COPPER TEST. 339 
 
 very narrow bore, tte results are by no means uniform. Very 
 uniform results, however, may be obtained in the following 
 manner. A quite thin and perfectly clean tube, of about the 
 10th of an inch in diameter, is drawn out into a small capil- 
 lary neck, as shown in Fig. 11, A. The coated copper is then 
 introduced, through the wider p^ ^^ 
 
 portion of the cooled tube, to 
 the point c, the neck of the 
 tube moistened with water or 
 wrapped with wet cotton, and 
 the wider end very carefully 
 fused shut, by a small blow- 
 
 n 1 it r • Tubes for Sublimation of Mercury. Natural size. 
 
 pipe ilame, when the fusion 
 
 is slowly advanced to the copper, as illustrated in B. The 
 capillary end of the tube may now be fused shut. When the 
 tube, thus prepared, is wiped and examined under the micro- 
 scope, the mercurial sublimate will be found at about the point 
 m, forming a narrow ring of well-defined globules. This method 
 also possesses the advantage of allowing the higher powers of 
 the microscope to be applied, since these tubes may readily be 
 prepared with walls not exceeding the 200th of an inch in thick- 
 ness. The tube, containing the sublimate, may be reserved for 
 future reference ; after long periods, however, the sublimate 
 deteriorates somewhat, and may even, if only in minute quan- 
 tity, entirely disappear. 
 
 4. 2 5.000 grain : if the acidulated solution be heated, and as the 
 liquid evaporates its place supplied with pure water, the 
 copper in a Httle time presents a silvery appearance, and 
 before long acquires a very decided, grey coating. When 
 the coated copper is heated in a tube of the above form, 
 it yields a sublimate visible to the unaided eye, and which, 
 under an amplification of about seventy-five diameters, is 
 found to consist of a ring of well-defined globules. In a 
 number of instances, over one hundred globules, varying 
 in size from the 1,000th to the 10,000th of an inch in 
 diameter, were counted in a single field of the objective ; 
 many of the globules measured over the 2,333d of an inch 
 in diameter. 
 
340 MERCURY. 
 
 0- 5"(r,^"ou grain : when the slip of copper employed measures 
 only about -2'uth by xoth of an inch in extent, the results 
 obtained are very similar to those described under 4. 
 6- xuo^uo grain : the copper, after continued heating and re- 
 newal of the evaporated liquid by water, acquires a quite 
 distinct metallic tarnish, and when heated in a tube, of 
 the above form, yields a very satisfactory globular subli- 
 mate. In some few instances, over one hundred globules 
 were obtained, several of which, singly, measured over the 
 1,750th of an inch in diameter ; the greater number of 
 the globules, however, were quite small : none less than 
 the 10,000th of an inch in diameter were counted. In a 
 majority of the experiments made, the sublimate contained 
 about fifty well-defined globules, most of which were usu- 
 ally in a single field of a fds inch object-glass. So far as 
 the evidence of the presence of mercury is concerned, this 
 quantity of corrosive sublimate, when manipulated in the 
 above manner, will yield just as satisfactory results as a 
 much larger quantity, the only difference being in the ab- 
 solute number and size of the globules obtained. 
 7. 5 u 0% grain : the copper, even after prolonged heating, un- 
 dergoes but little change in appearance. But when washed, 
 dried, and heated in a tube, as many as twenty satisfac- 
 tory mercurial globules were obtained, the largest of which 
 measured about the 3,000th of an inch in diameter ; the 
 diameter of most of them, however, varied from the 5,000th 
 to the 10,000th part of an inch. Most of the sublimates 
 obtained, contained from five to ten globules measuring or 
 exceeding the 5,000th of an inch in diameter. 
 For the identification of these mercurial globules, an ampli- 
 fication of about seventy-five diameters is generally the most 
 useful. Under this power, a globule measuring the 3,000th 
 part of an inch in diameter, is very readily identified: such a 
 globule, if a perfect sphere, would weigh only about the 15,000,- 
 000th part of a grain. So also, under this power, globules of 
 the 5,000th of an inch in diameter, are very distinct and quite 
 satisfactory : a globule of this size would weigh about the 
 70,000,000th of a grain. And, even, when of the 7,000th of 
 
COPPER TEST. 341 
 
 an inch, their spherical nature may still be determined with 
 considerable certainty : such a globule would weigh only about 
 the 190,000,000th part of a grain. But, under this ampliiica- 
 tion, globules of only the 10,000th of an inch in diameter, ap- 
 pear as mere opake points, under transmitted light. Under an 
 amplification of about two hundred and fifty, a globule of the 
 10,000th of an inch in diameter, may be satisfactorily determ- 
 ined; and even when of only the 15,000th of an inch, their spher- 
 ical outline may still be recognised with considerable certainty. 
 
 On account of the curvature of the glass tube, a -jih inch 
 object-glass, or an amplification of about two hundred and fifty, 
 is about the highest power that can be satisfactorily employed 
 for these identifications. When upon a flat surface, the true 
 nature of globules much smaller than any of those mentioned 
 above, can be readily determined. Thus, with a -g-th inch 
 objective, a globule, or " artificial star," measuring only the 
 25,000th of an inch in diameter, and weighing about the 9,000,- 
 000,000th of a grain, will present the characters of sphericity 
 and opacity, and reflect incident light. It need hardly be ob- 
 served, that it is not intended to imply, that quantities of mer- 
 cury in themselves no greater than these, can be recovered 
 from a solution and reproduced in the globular form. From the 
 above experiments, it would appear, that even under the most 
 favorable conditions, the least quantity of corrosive sublimate 
 from which the mercury can thus be reproduced, is about the 
 100,000th or at least the 500,000th part of a grain. 
 
 It may be remarked, that in the above experiments, the 
 amount of metallic mercury present in the corrosive sublimate, 
 was as 100 is to 135-5. It may also be added, that from these 
 experiments, it would appear that mercury is not as readily 
 volatilised by continued heating with boiling water, as is usu- 
 ally supposed. This view is also borne out by the experiments 
 of Fresenius (Quantitative Analysis, p. 641). 
 
 The test now under consideration, has an advantage over 
 ordinary liquid tests, in that it is not as readily afi'ected by 
 dilution. Thus, ten grains of a 100,000th solution of the mer- 
 curial compound, will yield after a time, even upon renewal of 
 the evaporated liquid, very nearly as good results as one grain 
 
342 MERCURY. 
 
 of a 10,000th solution. Beyond a certain limit, however, this, 
 like all other tests, will entirely fail to act. Another advantage 
 possessed by this test, is that while being applied to a solution, 
 the latter may be concentrated to almost any extent. 
 
 Fallacies. — The mere fact of a metallic deposit being formed 
 upon the copper, in the application of this test, is not in itself 
 positive evidence of the presence of mercury, especially if the 
 solution be acidulated and heated, since arsenic, antimony, sil- 
 ver, bismuth, platinum, palladium, and some few other metals 
 are deposited under similar conditions. Of these various metals, 
 however, the only ones that like mercury have a white silvery 
 appearance, are silver and bismuth. Moreover, the only ones 
 which like that metal, wiU deposit from cold solutions, are silver, 
 platinum, and palladium. When, thereforfe, the deposition takes 
 place from a cold solution, and has a bright silvery luster, or 
 acquires it by friction, the deposit is most probably mercury ; 
 but it might be silver. 
 
 Of the various metals that might thus be deposited, even 
 from heated acidulated solutions, the only ones that will vola- 
 tilise and yield a sublimate, when the coated copper is heated 
 in a reduction-tube, are mercury, arsenic, and antimony. But 
 the spherical nature, as well as the opacity of the globules un- 
 der transmitted light, and their bright silvery luster under inci- 
 dent light, of the mercurial sublimate, readily distinguish it 
 from the octahedral crystalline sublimate produced by arsenic, 
 and from the amorphous deposit .occasioned by antimony. 
 
 Metallic zinc, bismuth, cadmium, tin, silver, nickel, iron, 
 lead, arsenic, and antimony, will also, like copper, decompose 
 solutions of corrosive sublimate, with the formation of a coating 
 of metallic mercury upon the applied metal. But neither of 
 these metals have, for this purpose, any advantage over me- 
 tallic copper, and in most instances the reaction is very much 
 less dehcate than when that metal is employed. 
 
 So also, if the acidulated mercurial solution be placed in a 
 small platinum or gold dish and the metal touched, through 
 the solution, with a thin wire of zinc, iron, tin, or any other 
 of the above-named metals, the salt undergoes decomposition. 
 
NITRATE OF SILVER TEST. 343 
 
 by galvanic action, the mercury being deposited chiefly upon the 
 platinum or gold, but partly upon the other metal. Similar 
 results may be obtained, by applying a small slip of gold or 
 platinum-foil to a corresponding slip of tin, zinc or iron, or to a 
 small cylinder of either of these metals, and immersing the com- 
 bination in the acidulated mercurial solution. Some of these 
 galvanic combinations are extremely delicate in their reactions ; 
 but they are not as well adapted for the detection of very minute 
 quantities of the poison as the method by copper alone, as be- 
 fore described. 
 
 7. Nitrate of Silver. 
 
 This reagent decomposes neutral and acidulated solutions of 
 corrosive sublimate, with the production of a white, amorphous 
 precipitate of chloride of silver (AgCl), which is insoluble in 
 nitric acid. In its pure state, chloride of silver is very readily 
 soluble in ammonia, but as precipitated from the mercurial 
 solution, which itself yields a precipitate with ammonia, it is 
 soluble with difficulty in that alkali, and, unless very large 
 excess of the alkali be added, is soon replaced by a white, 
 granular deposit. 
 
 1. Yg-Q grain of corrosive sublimate, in one grain of water, 
 
 yields a very copious, white, curdy precipitate. 
 
 2. iToVo grain, yields a quite good precipitate, which, in the 
 
 mixture, dissolves with difficulty in ammonia. 
 
 3. 10,0 grain: a good deposit, which quickly disappears on 
 
 the addition of ammonia. 
 
 4. 5 0.0 grain, yields a quite fair precipitate. 
 5- TToWoo grain: a very satisfactory turbidity. 
 6. 5-oo%o"5 grain, yields a perceptible cloudiness. 
 
 This reagent is simply for the purpose of detecting the 
 presence of the chlorine of the corrosive sublimate. The reac- 
 tion of the reagent, is, of course, common to solutions of all 
 soluble chlorides and of free hydrochloric acid. If, however, 
 it be shown, by any of the other tests, that the solution also 
 contains mercury, then it follows, providing the solution is not 
 a complex mixture, that the metal existed as corrosive sub- 
 limate, since this is its only soluble chloride. 
 
344 MERCURY. 
 
 Other Reagents. — The mercury, from solutions of corro- 
 sive sublimate, may be precipitated, in a state of combination, 
 by several reagents other than those already described, but the 
 reactions of these are much less delicate and characteristic, 
 than those already considered. A few of these tests, however, 
 may be very briefly mentioned. 
 
 Ferrocyanide of potassium produces in solutions of the mer- 
 curial compound, a dirty-white precipitate, which is soluble in 
 excess of the precipitant. One grain of a 100th solution of 
 the salt, yields a very copious precipitate; and a similar quan- 
 tity of a 1,000th solution, a quite good deposit. This is about 
 the limit of the reaction of the test, for one grain of the solution. 
 
 Ferricyanide of potassium throws down from aqueous solu- 
 tions of the salt, a greenish-yellow, amorphous precipitate, which 
 is insoluble in excess of the precipitant. One grain of a 1,000th 
 solution of the mercurial compound, yields a quite good precip- 
 itate; a similar quantity of a 5,000th solution, yields only a 
 slight turbidity. 
 
 Protochromate of potash produces in quite strong solutions of 
 the salt, a greenish-yellow precipitate; but the Bichromate of 
 potash, occasions no visible reaction. 
 
 Separation from Organic Mixtures. 
 
 Since corrosive sublimate is readily precipitated, with more 
 or less decomposition, by various animal and vegetable princi- 
 ples, much of the poison, when added to mixtui-es of this kind, 
 may be present in a form insoluble in water. Under these 
 circumstances, however, sufficient of the mercury to be detected 
 by the ordinary reagents wiU usually remain in solution, even 
 in quite complex mixtures, and after standing for long periods. 
 AVe find, that the solid coagulum resulting from the precipitation 
 of the poison with albiimen, which is one of the most insoluble 
 compounds of this kind, when washed and dried, even to a 
 horny mass, stiU yields up some of the mercurial compound on 
 digestion with even cold distilled water; more of it to hot water, 
 and still more, when boiled with water acidulated with hydro- 
 chloric acid. 
 
RECOVERY FROM ORGANIC MIXTURES. 345 
 
 Suspected Solutions. — Any precipitate or mechanically sus- 
 pended matter present, is separated from the suspected solution 
 by a filter, and examined for any solid particles of the poison, 
 then washed with warm water, and reserved for future examina- 
 tion, if necessary.' A portion of the clear liquid may then be 
 acidulated with hydrochloric acid and boiled with a small slip 
 of bright copper-foil. If the copper quickly receives a metallic 
 coating, it is removed from the liquid, and other and larger 
 slips of the metal consecutively added, as long as they acquire 
 a deposit. If the deposit thus obtained consists of mercury, it 
 will usually present a greyish-white appearance, and acquire a 
 bright silvery luster when gently rubbed with the finger, or any 
 other soft body. The coated copper is then washed in alcohol 
 or ether, dried at a moderate temperature, one or more of the 
 slips heated in an appropriate reduction-tube, and any sub- 
 limate obtained, examined by a low power of the microscope. 
 
 If the method now described, yields positive results, these 
 may be confirmed, by examining other portions of the suspected 
 liquid, by some of the other tests for the poison; this, however, 
 is not really necessary, at least so far as the presence of mer- 
 cury is concerned. A portion of the liquid should be concen- 
 trated to a small volume, and allowed to stand in a cool place 
 for some hours, or longer if necessary, in order that the poison, 
 if present, may separate in its crystalline state. Any crystals 
 thus obtained, after being carefully washed, are dissolved in a 
 small quantity of water, and a portion of the solution tested for 
 chlorine, by nitrate of silver. 
 
 Should the copper test, after prolonged heating and concen- 
 tration of the liquid, fail to reveal the presence of mercury, it 
 is quite certain that the other tests for that metal would also 
 fail, since they are much less delicate in their reaction than 
 the former. Under these circumstances, any organic solids 
 separated from the suspected liquid, by filtration, are boiled for 
 about ten minutes with pure water, or better still, so far as 
 the recovery of mercury is concerned, with water strongly 
 acidulated with hydrochloric acid; the cooled liquid is then 
 filtered, and the filtrate examined by the copper test, in the 
 manner above described. It is obvious, that the employment 
 
346 MERCURY. 
 
 of hydrochloric acid, in the preparation of the liquid, will, in 
 the event of the detection of mercury, preclude the possibility 
 of proving that the metal existed as a chloride, at least so far 
 as the liquid under examination is concerned. 
 
 Another method for the recovery of corrosive sublimate, 
 from organic liquids, is to violently agitate the concentrated 
 liquid, for some minutes, in a small bottle or a stout tpst-tube, 
 with about twice its volume of pure commercial ether, in which, 
 as we have already seen, the salt is freely soluble. When the 
 liquids have completely separated, which will usually require a 
 repose of only a few minutes, the ethereal fluid is carefully 
 decanted into a watch-glass, and allowed to evaporate sponta- 
 neously. Any saline residue thus obtained, is examined in the 
 usual manner, a portion of it being first examined by some of 
 the tests for the poison in its solid state. In the application of 
 this method, it should be borne in mind, that ether does not 
 extract the whole of the salt from its aqueous solutions. 
 
 Vomited matters. — The matters ejected from the stomach 
 may be examined in the same manner as just described, for 
 suspected solutions. If an antidote, such as white of egg or 
 gluten, were administered, the organic solids of the vomited 
 matters may require long boiling with water strongly acidulated 
 with hydrochloric acid, for the complete separation of the poison. 
 
 Contents of the Stomach. — As corrosive sublimate is readily 
 soluble, it is not often found in its solid state in the stomach; 
 however, this examination should not be omitted. The mass is 
 then stirred with sufficient water to make it quite liquid, the 
 mixture gently heated for some time on a water-bath, the cooled 
 liquid filtered, and the solids on the filter well washed with 
 pure water, the washings being collected with the first filtrate. 
 The filter, with its contents, should be reserved. The clear 
 liquid is then concentrated to an appropriate volume, and, if 
 necessary, again filtered. 
 
 A portion of the filtrate, thus obtained, is acidulated with 
 hydrochloric acid, and boiled with a very small slip of bright 
 copper-foil. If this fails to receive a metallic coating, the ap- 
 plication of the heat should be continued until the liquid is 
 evaporated to near dryness, before concluding that the poison 
 
RECOVERY FROM ORGANIC MIXTURES. 347 
 
 is entirely absent. On the other hand, if the copper quickly 
 receives a metallic deposit, it is removed from the liquid, and 
 other slips of the metal added, as long as they become coated. 
 The mercurial deposit, as already pointed out, is readily distin- 
 guished from that produced by arsenic, antimony, and most 
 other metals that are thus deposited, by its bright silvery 
 appearance, at least when rubbed. The coated copper is thor- 
 oughly washed in alcohol or ether, dried, then heated in a 
 reduction-tube, and any sublimate thus obtained examined by 
 the microscope. 
 
 Another portion of the filtrate may be acidulated with hydro- 
 chloric acid, and treated with excess of a solution of proto- 
 chloride of tin, when, if it yields a dark grey precipitate, the 
 mixture is gently heated until the precipitate has completely 
 subsided; the supernatant fluid is then decanted, the residue 
 washed with hot water, then boiled with a little water strongly 
 acidulated with pure hydrochloric acid, which will cause any 
 finely divided mercury present to collect into comparatively 
 large globules. It must be remembered that various organic 
 solutions yield with the tin reagent, a white precipitate, which 
 may more or less conceal the color of the mercurial deposit. 
 Under these circumstances, the precipitate is boiled for some 
 time with a strong solution of caustic potash, which will dis- 
 solve the organic matter, leaving the mercury in the form of a 
 greyish-black powder. This is then boiled with a little diluted 
 hydrochloric acid, in the manner just described. 
 
 If a portion of the filtrate be acidulated with hydrochloric 
 acid and treated with sulphuretted hydrogen gas, any of the 
 poison present will give rise to sulphuret of mercury, which 
 will be thrown down as a black precipitate, at least if excess 
 of the reagent has been employed. After the precipitate has 
 completely subsided, it may be collected on a filter, washed, 
 and then dried. Its mercurial nature may be established, by 
 mixing it with several times its volume of recently ignited 
 carbonate of soda, and heating the mixture in a reduction-tube, 
 when it will undergo decomposition with the production of a 
 globular sublimate of metallic mercury, readily identified by 
 means of the microscope. 
 
348 MERCURY. 
 
 The positive reaction of either of the foregoing tests, would, 
 of course, simply indicate the presence of the mercury of the 
 corrosive sublimate. For the purpose of showing the presence 
 of the chlorine, it is best to agitate a portion of the filtrate with 
 ether, in the manner already directed, then allow the ethereal 
 solution to evaporate spontaneously, dissolve the residue in a 
 small quantity of warm water, and treat the solution with nitrate 
 of silver. As the alkaline chlorides are insoluble in ether, the 
 detection of chlorine under these circumstances, would not be 
 open to the objection that would hold if the silver reagent were 
 applied directly to the original filtrate; especially will this objec- 
 tion be guarded against, if the ethereal liquid, on evaporation, 
 leave the poison in its crystalline state. 
 
 Should the methods already given fail to reveal the presence 
 of mercury, in the filtrate, then the organic solids left upon the 
 filter may be examined. For this purpose, the mass is trans- 
 ferred to a porcelain dish, the solids cut into small pieces, and 
 boiled for about twenty minutes with pure water, the mixture 
 being frequently stirred by means of a glass rod. When the 
 mixture has cooled, the liquid portion is separated by a filter, 
 the filtrate concentrated to a small volume, and then examined 
 in the manner before directed, for the first filtrate. Instead of 
 boiling the organic solids with pure water, they may be boiled 
 with water containing hydrochloric acid, until they are entirely 
 disintegrated. If, howevei-, this method be employed, the pres- 
 ence of the chlorine of the corrosive sublimate could not be 
 established. 
 
 Another method for the examination of the above organic 
 solids, is to boil the mass with a somewhat concentrated solution 
 of caustic potash, until the solids are entirely decomposed, and 
 then treat the mixture with a solution of protochloride of tin, 
 the heat being continued for some little time after the addition 
 of the tin reagent. Any dark grey precipitate thus obtained, 
 is carefully collected, washed, and examined in the manner 
 already described. 
 
 From the Tissues. — If there has been a failure to detect 
 corrosive sublimate under one or other of the conditions now 
 described, it will no longer be possible to show the presence of 
 
SEPARATION FROM THE TISSUES. 349 
 
 the poison as a whole; but the presence of the absorbed mer- 
 cury may be shown, in some of the soft tissues of the body. 
 For the recovery of the absorbed metal, various methods have 
 been advised. The finely divided tissue, as about ten ounces 
 of the liver, may be made into a thin paste with water con- 
 taining about one-sixth of its volume of pure hydrochloric acid, 
 and the whole heated at about the boiling temperature, until the 
 organic solids are completely disintegrated, which wiU usually 
 require about two hours. The mass is then allowed to cool, 
 transferred to a linen strainer, -the strained liquid filtered, and 
 then concentrated to a comparatively small volume. A portion 
 of the liquid may now be heated to the boiling temperature, 
 and examined by the copper test, employing at first only a 
 very minute slip of the metal. In applying this test, it should 
 be remembered that the copper, after prolonged heating, may 
 acquire a very distinct stain or tarnish, even in the absence of 
 mercury or of any other metal. Before heating the copper in 
 a reduction-tube, it should be very thoroughly washed, first in 
 water containing a little ammonia. Should the first portion of 
 liquid examined, fail to reveal the presence of mercury, then 
 another and larger portion or even the whole of the remaining 
 liquid, should be examined in a similar manner. 
 
 The copper test will serve to recover very minute quantities 
 of mercury from very complex organic liquids. A portion of a 
 human liver, free from mercury, was boiled with diluted hy- 
 drochloric acid, in the manner just described, and the liquid 
 strained. To one hundred grain-measures of the strained fluid, 
 the 1,000th part of a grain of corrosive sublimate was added — 
 the poison then being under a dilution of 100,000 times its 
 weight of the organic liquid — and the mixture boiled with a 
 very small slip of bright copper-foil. After a little time, the 
 copper received a very distinct metallic stain, and when washed, 
 dried, and heated in a small reduction-tube, yielded a sublimate, 
 which, under the microscope, was found to contain over one 
 hundred characteristic globules of mercury. 
 
 Should the examination of the first portion of the above 
 liquid indicate the presence of mercury, and it be desired to 
 pursue the investigation, another portion may be treated with 
 
350 MERCURY. 
 
 excess of protocliloride of tin, and gently warmed, until the 
 precipitate has completely deposited. The precipitate is then 
 collected, washed, and boiled in a porcelain evaporating dish 
 with a solution of caustic potash, until the organic matter is 
 dissolved and the residue assumes a dark grey color. The clear 
 supernatant Kquid is then decanted, and the residue repeatedly 
 washed with hot water, then boiled with hydrochloric acid, 
 which will cause any finely divided mercury present, if entirely 
 free from foreign matter, to coalesce into globules. 
 
 Another, and in some cases preferable method for breaking 
 up the animal tissues, is by means of hydrochloric acid and 
 chlorate of potash, in the manner described for the recovery of 
 absorbed arsenic. The finely divided tissue is treated with 
 about one-fourth of its weight of pure concentrated hydrochloric 
 acid, and the whole made into a thin paste, by the addition of 
 water. The mixture is then heated to about the boiling tem- 
 perature, and small quantities of powdered chlorate of potash 
 occasionally added, until the mass becomes perfectly homogene- 
 ous, after which it is kept at a gentle heat, until the odor of 
 chlorine has entirely disappeared. The mixture is now allowed 
 to cool, the liquid filtered, and the solid matters on the filter 
 well washed with hot water. The filtrate may now be partially 
 neutralised with pure carbonate of soda, and concentrated, until 
 its volume is about five times that of the hydrochloric acid em- 
 ployed in the destruction of the organic matter. 
 
 The Hquid thus obtained, after filtration if necessary, is 
 exposed for several hours to a slow stream of sulphuretted hy- 
 drogen gas, then gently heated, and allowed to stand in a mod- 
 erately warm place for about fifteen hours. Any mercury 
 present, will now be in the precipitate, in the form of the black 
 sulphuret, together with more or less organic matter, the color 
 of which may disguise that of the mercurial compound. The 
 precipitate is collected upon a small filter, well washed, and 
 then transferred to a porcelain dish, treated with a proportion- 
 ate quantity of concentrated hydrochloric acid, and pure nitric 
 acid added drop by drop, until complete solution has taken place. 
 By this treatment, with the mixed acids, the mercury of the 
 mercurial sulphuret, will be dissolved to protochloride of the 
 
FAILURE TO DETECT. 351 
 
 metal, while the sulphur will be eliminated as a yellow adherent 
 mass, which, as fast as it forms, should be removed, by means 
 of a glass rod. On now cautiously evaporating the solution to 
 dryness on a water-bath, the chloride of mercury will be left as 
 a white crystalline mass ; if the eliminated sulphur was not 
 removed from the mixture, the residue may consist largely of 
 the sulphate of mercury. 
 
 A portion of the saline residue, thus obtained, may be tested 
 for the poison in its solid state, and another portion dissolved in 
 a small quantity of water, and the solution examined by the 
 copper test. If the addition of water produces an insoluble 
 yellow sulphate of mercury, its solution may be readily eifected 
 by the addition of a drop or two of hydrochloric acid. 
 
 From the Urine. — About twelve ounces of the urine are 
 strongly acidulated with hydrochloric acid, evaporated to a small 
 volume, filtered, the filtrate boiled with a small slip of bright 
 copper-foil, and the latter washed, dried, and examined in the 
 usual manner. Another method for the examination of this 
 fluid, is to concentrate it to near dryness, and then destroy the 
 organic matter by means of hydrochloric acid and chlorate of 
 potash, in the manner described for the recovery of the poison 
 from the tissues. If the first of these methods be adopted and 
 there is a failure to detect the metal, any solids separated by 
 filtration should be examined. 
 
 Dr. Thudichum remarks (Pathology of the Urine, p. 408), 
 that in aU cases, where the urine contains mercury, there is at 
 the same time a peculiar albuminous substance present in it, 
 which with nitric acid yields a faint reaction of albumen. A 
 substance is also present, having the reactions of sugar. In 
 some cases of mercurialism, he adds, the metal only appeared 
 in the urine at intervals, even where the symptoms had under- 
 gone no remission. 
 
 Failure to detect the Poison. — It has not unfrequently hap- 
 pened, in acute corrosive sublimate poisoning, that there was a 
 failure to detect the poison in any part of the dead body. In 
 a case quoted by Dr. Beck (Med. Jur., ii, p. 638), in which a 
 woman had poisoned herself with this substance, not a trace of 
 the poison was found either in the matters vomited during life. 
 
352 MERCURY. 
 
 or in the contents of the stomach after death. So, also, in a 
 case cited by Wharton and Stills (Med. Jur., p. 538), none of 
 the poison was detected in the stomach and intestines of a young 
 man who had taken three drachms of corrosive sublimate, and 
 died from its effects on the sixth day. In another instance, 
 recorded by Dr. Taylor (On Poisons, p. 471), in which two 
 drachms were swallowed, and death occurred on the fourth day, 
 a chemical examination of the stomach, blood, and tissues failed 
 to reveal the presence of mercury. 
 
 According to the observations of I. L. Orfila, absorbed mer- 
 cury is eliminated from the system chiefly by means of the 
 kidneys. In examining the urine of patients treated with mer- 
 curial preparations, he found the metal five days after it had 
 ceased to be taken, but in eight days it was no longer discov- 
 ered. In experiments upon dogs, he found the metal in the 
 tissue of the stomach and liver of some of the animals, as late 
 as the eighteenth day, but in others, similarly treated, it had 
 entirely disappeared. (Orfila's Toxicologic, 1852, i, p. 680.) 
 
 When mercury remains in the body at the time of death, 
 it, like arsenic, may be recovered after very long periods. In 
 a case of corrosive sublimate poisoning, which we examined 
 several years since, and in which death occurred on the fourth 
 day, the metal was readily detected in the stomach and liver of 
 the body, after it had been buried nine months : none of the 
 other organs were chemically examined. It need hardly be 
 remarked, that, since mercurial preparations are so frequently 
 taken medicinally, the detection of minute traces of the metal 
 in the dead body, would not in itself be any evidence that it 
 was the cause of death. 
 
 Quantitative Analysis. — The quantity of corrosive subH- 
 mate present in a solution of the salt, may be readily estimated 
 by precipitating the metal as sulphuret of mercury. For this 
 purpose, the solution, acidulated with hydrochloric acid, is satu- 
 rated with a slow stream of washed sulphuretted hydrogen gas, 
 after which it is allowed to stand in a moderately warm place, 
 until the precipitate has completely subsided; the precipitate is 
 then collected on a small filter of known weight, washed with 
 
QUANTITATIVE ANALYSIS. 353 
 
 pure water until the washings no longer have an acid reaction, 
 dried on a water-bath at 212° F., and weighed. One hundred 
 parts by weight, of the dried sulphuret of mercury, correspond 
 to 116"81 parts of anhydrous corrosive sublimate. 
 
 If in the application of the tin test, a known quantity of the 
 mercurial solution was employed, any globules of metallic mer- 
 cury obtained, may be carefully washed, dried, and weighed. 
 One hundred parts p{ the pure metal, represent 135-5 parts of 
 corrosive sublimate. 
 
 23 
 
354 LEAD. 
 
 OHAPTEE YII. 
 
 LEAD, COPPER, ZINC. 
 
 Section I. — Lead. 
 
 History and Chemical Nature. — Lead is one of the elementary 
 metals. Its symbol is Pb ; its combining equivalent 103-57 ; 
 and its density 11 -ii. It is found in nature associated with 
 several other elements, but it occurs principally as sulphuret of 
 lead, or galena. Lead has a bluish-grey color and strong me- 
 tallic luster ; it is quite soft, being easily scratched by the 
 finger-nail, and leaves a well-known mark upon white paper. 
 It is very malleable, and fuses at about 620° F. 
 
 In its pure state, lead is unacted upon by pure water. But 
 if air be present in the liquid, or its surface be freely exposed 
 to the action of the atmosphere, the metal rapidly becomes cor- 
 roded, and gives rise to oxide of lead, which partly unites with 
 water and partly with carbonic acid, forming a hydrated oxy- 
 carbonate of lead. This compound partly deposits upon the 
 lead as silky scales or falls as a precipitate, while a portion re- 
 mains mechanically suspended in the liquid ; at the same time, 
 some little of the compound becomes dissolved. When, how- 
 ever, the water holds in solution certain salts, such as the 
 carbonates, sulphates or the phosphates, an insoluble crust of 
 lead-salt slowly deposits upon the metal and protects it from 
 further action, and thus none of the lead is dissolved. On the 
 other hand, the presence of chlorides and of nitrates, increase 
 the corrosive action of water. 
 
 Lead is readily soluble in diluted nitric acid, especially upon 
 the application of heat, with the formation of nitrate of lead 
 and the evolution of binoxide of nitrogen. Cold diluted sul- 
 phuric acid fails to dissolve it, but the hot concentrated acid 
 dissolves it to sulphate of lead, with the evolution of sulphurous 
 
PHYSIOLOGICAL EFFECTS. 355 
 
 acid gas. Hydrochloric acid, even under the application of heat, 
 has but little action upon the metal. Heated on charcoal before 
 the blow-pipe flame, it gives rise to a yellow or brownish incrust- 
 ation of oxide of lead. 
 
 Physiological Effects. — In its metallic state, lead seems to be 
 inert. But all the compounds of the metal that are soluble in 
 water or in the animal juices, are more or less poisonous. Acute 
 poisoning by the preparations of lead has been of rare occur- 
 rence, and has chiefly been the result of accident. 
 
 Of the salts of lead, the acetate, or sugar- of lead, is one of 
 the most active, and has more frequently been taken as a poi- 
 son than any of the other compounds. This salt, however, is 
 poisonous only when taken in large quantity. Van Swieten 
 mentions an instance in which it was given to the amount of a 
 drachm daily for ten days before it caused any material symp- 
 tom. (Christison, On Poisons, p. 430.) Cases are not wanting, 
 however, in which it produced speedy and violent symptoms, 
 and even death. 
 
 Acetate of Lead. 
 
 Symptoms. — When an overdose of acetate of lead is swal- 
 lowed, the patient usually experiences at first a nauseous me- 
 tallic taste in the mouth, with a sense of constriction or burning 
 heat in the fauces and epigastrium. These effects are followed, 
 sooner or later, by severe gastric and abdominal pains, which 
 are generally relieved, but sometimes increased by pressure ; 
 sometimes the pain is constant, at others intermittent. There 
 is also nausea, and sometimes frequent vomiting of a yellowish 
 or blaekish liquid ; in some instances, the vomiting has been 
 very slight. The thirst is frequently very urgent ; the skin 
 cold, but sometimes hot, and generally covered by a clammy 
 perspiration ; the countenance anxious ; the strength greatly 
 prostrated ; the pulse slow and feeble, but often accelerated. 
 In some instances there has been severe and even bloody purg- 
 ing; but generally the bowels are obstinately constipated, there 
 being either no discharges or the matters passed being hard, dry 
 and black, and their discharge attended with pain. Sometimes 
 
356 LEAD. 
 
 the limbs become affected with spasms, and a sense of constric- 
 tion. The urine is usually diminished in quantity. The intel- 
 lect generally remains clear. 
 
 It is well known that the frequently repeated introduction 
 of even very minute quantities of any of the preparations of 
 lead into the system, may after a time induce serious symptoms. 
 Under these circumstances, the patient experiences general de- 
 pression, loss of appetite, a metallic taste in the mouth, and 
 generally great thirst. The throat becomes dry, the breath 
 fetid, the countenance dull and anxious, the skin dry and of a 
 dull yellow color, the bowels constipated, and the urine gener- 
 ally diminished. At the same time, a blue line forms along the 
 margins of the gums ; and there is more or less uneasiness or 
 pain in the abdomen. As the case advances, the pain in the 
 abdomen becomes very severe, and more or less constant : the 
 walls of this cavity are generally hard and depressed. These 
 effects are frequently followed by sharp pains in the extremi- 
 ties, muscular emaciation and paralysis. 
 
 In a case recently reported by Dr. G. A. Kunkler, the 
 external application of white-lead to a scalded surface, as a 
 dressing, produced unmistakable symptoms of lead colic — acute 
 abdominal pain, retraction of the umbilicus, constipation, and 
 slight discoloration of the gums. (Brit, and For. Med.-Chir. 
 Rev., Oct., 1857, p. 525.) 
 
 When Fatal. — In a case quoted by Dr. Beck, a soldier who 
 swallowed an unknown quantity of acetate of lead in solution, 
 was soon seized with the most violent symptoms, indicative of 
 gastric inflammation, and died in great agony at the end of 
 three days. (Med. Jur., i, 690.) Dr. Taylor refers to two 
 cases in which Goulard's extract — which is a solution of the 
 subacetate of lead — was taken in unknown quantity by two 
 children, aged respectively four and six years, and they both 
 died within thirty-six hours. The symptoms were at first vio- 
 lent vomiting and purging : in one case they resembled those 
 of Asiatic cholera. (Op. cit., p. 482.) In a case mentioned 
 by Dr. Christison (On Poisons, p. 430), the same preparation 
 of lead was taken in unknown quantity by a soldier. The first 
 symptoms could not be ascertained, but on the second day, 
 
ANTIDOTES. 357 
 
 he was affected with loss of appetite, paleness, costiveness, and 
 excessive debility; on the third day, he had severe colic, draw- 
 ing in of the abdomen, loss of voice, cold sweats, locked jaw, 
 and violent convulsions, and expired before the evening of the 
 same day. 
 
 Fatal Quantity. — In the few fatal cases of acute poisoning 
 by this substance that have occurred, the quantity taken could 
 not be accurately determined. Instances are reported in which 
 doses of about an ounce were taken without producing any very 
 serious results. On the other hand, a case is quoted by Dr. 
 Christison, in which two doses of a drachm each taken by a 
 man, with an interval of several hours between the doses, pro- 
 duced acute pain in the abdomen, bilious vomiting, loss of 
 speech, delirium, profuse sweating, and slow pulse ; with the 
 aid of treatment, the patient recovered. 
 
 Treatment. — In acute poisoning by the acetate of lead, the 
 stomach should be immediately emptied by the administration 
 of an emetic of sulphate of zinc ; and its action followed by 
 large draughts of milk containing white of egg. Various chem- 
 ical antidotes have been proposed. Among these the most use- 
 ful is sulphuric acid in the form of a solution of sulphate of 
 magnesia or of soda. Either of these salts would decompose 
 the lead compound with the formation of the insoluble and inert 
 sulphate of lead. The alkaline sulphurets have also been rec- 
 ommended. They would give rise to the insoluble sulphuret of 
 lead. These salts, however, are in themselves poisonous in 
 large doses, and their use as antidotes has not been as success- 
 ful as upon chemical grounds might have been expected. The 
 hydrated sesquisulphuret of iron has been strongly recommended 
 by M. Bouchardat ; and its efficacy has been recently confirmed 
 in a case reported by M. Lepage. As this compound is inert, 
 it may be administered in large quantity. The alkaline carbon- 
 ates and bicarbonates are inadmissible, as they would give rise 
 to the carbonate of lead, which is equally poisonous with the 
 acetate of the metal. 
 
 POST-MOETEM APPEARANCES. — In the case already cited from 
 Dr. Beck, the mucous membrane of the stomach was found 
 abraded in several places, particularly near the pylorus ; and 
 
358 LEAD. 
 
 the oesophagus, stomach, duodenum, mesentery, liver, and spleen 
 were in a state of high inflammation. In the two cases men- 
 tioned by Dr. Taylor, the mucous membrane of the stomach 
 was found of a grey color, but otherwise perfectly healthy ; and 
 the intestines were much contracted. In the fatal case cited by 
 Dr. Christison, the lower end of the oesophagus, the whole 
 stomach and duodenum, part of the jejunum, and the ascending 
 and transverse colon, were found much inflamed ; and the vil- 
 lous coat of the stomach appeared as if macerated. 
 
 It is necessary to bear in mind, that acetate of lead has caused 
 death without leaving any well-marked morbid appearance in the 
 body. 
 
 Chemical Properties. 
 
 General Chemical Nature. — Acetate of lead, as usually 
 found in the shops, is in the form of white, crystalline masses, 
 which have a density of about 2-6, a slight, vinegar-like odor, 
 and a sweetish, astringent taste. In its crystalline state, this 
 salt consists of one equivalent of the protoxide of lead, one of 
 acetic acid, and three equivalents of water (PbO, C4H3O3, 3 Aq) ; 
 it crystallises in four-sided prisms. When the crystals are ex- 
 posed to dry air, they slightly effloresce, and after a time 
 become partially converted into the carbonate of lead, from the 
 absorption of carbonic acid from the atmosphere. When mod- 
 erately heated, they fuse and give off their water of crystal- 
 lisation ; at higher temperatures, the salt undergoes complete 
 decomposition, leaving a black residue consisting of a mixture 
 of charcoal and metallic lead. 
 
 Solubility. 1. In water. — When finely powdered crystallised 
 acetate of lead is agitated for a few minutes with its own weight 
 of water, at a temperature of 60°- F., and the liquid quickly 
 filtered, crystals of the salt immediately begin to separate from 
 the filtrate ; if this mixture be allowed to evaporate spontane- 
 ously, it leaves a crystalline residue, indicating that the filtered 
 fluid originally held in solution one part of the salt in 1-62 
 parts of the liquid. 
 
 When the powdered salt is agitated for a few minutes with 
 an equal weight of water at a temperature of 60° (F., and the 
 
SPECIAL CHEMICAL PROPERTIES. 359 
 
 mixture allowed to stand at about the same temperature for 
 forty-eight hours, and the liquid then filtered, the filtrate con- 
 tains only one part of the salt in 2"67 parts of water. 
 
 From these experiments, it is obvious th-at the mere act of 
 agitation very much increases the solubility of this salt in water. 
 This circumstance may, in part at least, account for the dis- 
 crepant statements of observers in regard to the solubility of 
 the salt. 
 
 2. In Alcohol. — When large excess of the pulverised salt is 
 agitated for a few minutes with pure alcohol of 97 per cent., 
 and the solution quickly filtered, the filtrate contains one part 
 of the salt in twenty parts of the liquid. But, if after agitating 
 the mixture for a few minutes, it be allowed to stand quietly 
 for twenty-four hours, and the liquid then filtered, the filtrate 
 contains only one part of the salt in about sixty-five parts of 
 the menstruum. 
 
 The more dilute the alcohol, other conditions being equal, 
 the greater wiU be the quantity of the salt that it will dissolve. 
 
 3. In Ether.- — Absolute ether, under any circumstance, fails 
 to dissolve an appreciable trace of the salt. 
 
 Special Chemical Properties. — When acetate of lead, in 
 its solid state, is moistened with a solution of iodide of potas- 
 sium, it assumes a bright yellow color, due to the formation of 
 iodide of lead. The least visible quantity of the salt will ex- 
 hibit this reaction. Thus a residue containing only the 1,000th 
 part of a grain of oxide of lead, will yield a very satisfactory 
 bright yellow coloration ; and even the 10,000th of a grain, 
 when deposited at one point, will assume a distinct yellow hue. 
 The iodide of lead thus produced, is slowly soluble in large ex- 
 cess of the reagent. 
 
 If a small portion of the salt be introduced into a drop of 
 chromate of potash solution, it also assumes a bright yellow 
 color, chromate of lead being formed. Crushing the crystal, 
 facilitates the formation of the yellow compound. 
 
 When gradually heated on a piece of porcelain, acetate of 
 lead fuses to a clear liquid, boils, and then becomes reduced to 
 a white, anhydrous mass ; if the heat be continued, the mass 
 again fuses, then becomes dry and charred, and slowly assumes 
 
360 LEAD. 
 
 a yellowish or reddish-brown color. This residue consists of a 
 mixture, in variable proportions, of different oxides of lead. 
 Almost the least visible crystal of the salt, when thus treated, 
 leaves a brownish residue, apparently several times greater than 
 the crystal employed. The carbonate of lead, when treated in 
 this manner, does not fuse ; but it is slowly decomposed with 
 the production of a similar reddish-brown residue. 
 
 Heated upon a piece of charcoal in the inner blow-pipe 
 flame, acetate of lead fuses, then undergoes decomposition 
 with the production of bright, malleable globules of metallic 
 lead, and the formation of a yellow incrustation of oxide of 
 lead. The carbonate of lead, mider these circumstances, yields 
 at first a brownish mass, which soon furnishes bright, metallic 
 globules. 
 
 When acetate of lead is placed in a small quantity of ses- 
 quichloride of iron solution, it slowly dissolves to a fine red 
 solution of acetate of sesquioxide of iron (FcaOg, 3 C4H3O3). If 
 the salt be heated in a test-tube with concentrated sulphuric 
 acid, it undergoes decomposition with the evolution of pungent 
 vapors of acetic acid. When heated with a mixture of equal 
 volumes of alcohol and sulphuric acid, it evolves acetic ether, 
 readily recognised by its peculiar, aromatic odor. These reac- 
 tions are simply due to the acetic acid of the lead-salt, and are 
 common to all acetates. 
 
 Pure aqueous solutions of acetate of lead, are colorless, odor- 
 less, and have a sweetish, styptic taste, and, if not too dilute, 
 a feebly acid reaction. .When a solution of this kind is allowed 
 to evaporate spontaneously, the salt is left in the form of white, 
 crystalline needles. 
 
 In the following examinations, in regard to the behavior of 
 reagents with solutions of lead, the pure crystallised acetate 
 was dissolved in water very slightly acidulated with acetic acid. 
 The fractions employed, indicate the fractional part of a grain 
 of the protoxide of lead (PbO) in solution in one grain of the 
 hquid. Except when otherwise indicated, the results refer to 
 the behavior of one grain of the solution. One part of the 
 protoxide of lead, represents 1-696 parts of crystallised acetate 
 of lead. 
 
SULPHURETTED HYDROGEN TEST. 361 
 
 1. Sulphuretted Hydrogen. 
 
 This reagent, either in its gaseous state or in the form of 
 an alkaline siilphuret, throws down from neutral, acidulated, 
 and alkaline solutions containing lead, a black, amorphous pre- 
 cipitate of sulphur et of lead (PbS), which is insoluble in the 
 caustic alkalies and in the diluted mineral acids. Hot con- 
 lentrated hydrochloric acid dissolves the precipitate, with the 
 evolution of sulphuretted hydrogen and the fbrmation of chlo- 
 ride of lead, which, unless the quantity be very minute, sep- 
 arates as the liquid cools in the form of beautiful crystalline 
 plates. 
 
 The precipitate is readily decomposed by hot nitric acid, 
 with the formation of nitrate of lead and the separation of free 
 sulohur ; if the acid be concentrated and the heat continued, 
 the separated sulphur becomes oxidised into sulphuric acid, 
 which, displacing the nitric acid, unites with the lead, forming 
 sulphate of lead. The sulphate of lead thus formed, gen- 
 erally separates in the form of a white, granular powder, but 
 sometimes in the form of small, briUiant, crystalline plates ; 
 if, however, the quantity of sulphate of lead produced be only 
 small, it may remain in solution in any excess of nitric acid 
 present. 
 
 In examining the limit of the reaction of this reagent, a 
 slow stream of the washed sulphuretted gas was passed into ten 
 grains of the lead solution, contained in a small test-tube. 
 
 1. 100th solution of oxide of lead (=3Vth grain PbO), yields an 
 
 immediate, copious, black deposit. When the precipitate 
 is dissolved in the mixture, by excess of hydrochloric 
 acid, it yields a white precipitate of crystalline needles of 
 chloride of lead. 
 
 2. 1,000th solution, yields an immediate precipitate. When a 
 
 solution of this strength is exposed to the vapor of sulphu- 
 retted hydrogen, its surface becomes covered with a black 
 pellicle of the lead-sulphuret. 
 
 3. 10,000th solution : the first bubble of the reagent produces 
 
 a deep brown coloration; and a few bubbles produce a 
 
362 LEAD. 
 
 deep brown ttirbidity. After saturating the solution with 
 the reagent, and allowing it to stand an hour, a very sat- 
 isfactory, black deposit separates. 
 
 4. 50,000th solution: after a few moments, the Kquid assumes 
 
 a distinct brown color, and very soon presents a brown 
 turbidity ; after a few hours, distinct brownish flakes sep- 
 arate. 
 
 5. 100,000th solution : after some minutes, the liquid assumes a 
 
 distinct brownish tint, and soon afterwards becomes turbid ; 
 
 after some few hours, the brownish color deepens, but no 
 
 deposit separates. 
 ■ 7. 250,000th solution : after several minutes, the liquid assumes 
 
 a just perceptible cloudiness, with a faint brownish tint, 
 
 which is only distinctly observed when compared with a 
 
 clear solution, and best seen by looking through the liqud 
 
 from the top. 
 The formation of the precipitate, from very dilute solu- 
 tions, is much facilitated by heating the mixture. The deli- 
 cacy of the reaction of this test has been variously stated. 
 Thus, Pfaff placed the limit of the brown coloration, at one 
 part of lead oxide, in the form of nitrate, in 100,000 parts 
 of liquid; Lassaigne at 200,000; and Harting at 350,000 parts. 
 As, however, neither of these observers state the amount 
 of the solution operated upon, these discrepancies are readily 
 explaiaed. 
 
 Fallacies. — The production of a black precipitate by this 
 reagent is common to solutions of several other metals, besides 
 lead. The true nature of the lead precipitate may be estab- 
 lished, by dissolving it, by the aid of heat, in diluted nitric acid 
 containing just sufficient of the acid to effect decomposition, and 
 then testing the solution with either iodide of potassium, chro- 
 mate of potash, or diluted sulphuric acid ; or, after filtration, the 
 nitric acid solution may be evaporated to dryness, and the resi- 
 due examined by any of the tests already mentioned, for oxide 
 of lead when in its solid state. 
 
 When strongly heated in a reduction-tube, sulphuret of 
 lead is converted into a hard, brittle mass, but fails to yield 
 a sublimate. 
 
SULPHURIC ACID TEST. 363 
 
 2. Sulphuric Acid. 
 
 This acid and its soluble salts throw down from solutions of 
 salts of lead a heavy, white precipitate of sulphate of lead 
 (PbO, SO3), which is soluble in large excess of the fixed alka- 
 lies, and in some of the salts of ammonia, but very sparingly 
 soluble in diluted nitric and hydrochloric acids. Strong nitric 
 acid dissolves it in limited quantity to a clear solution. Con- 
 centrated hydrochloric acid dissolves it rather readily, especially 
 upon the application of heat, yielding crystals of chloride of 
 lead, as the mixture cools. 
 
 From very dilute solutions of salts of lead, the precipitated 
 sulphate does not separate until after some time : it then de- 
 posits in the form of small granules. Solutions of the alkaline 
 carbonates and bicarbonates convert sulphate of lead, even at 
 ordinary temperatures, into carbonate of lead ; the solutions of 
 the alkaline carbonates, but not those of the bicarbonates, dis- 
 solve some of the lead compound in this process (H. Rose). 
 From an alkaline solution of sulphate of lead, the metal is pre- 
 cipitated by sulphuretted hydrogen, as sulphuret of lead. 
 !• TW grain of oxide of lead, in one grain of liquid, yields 
 with a drop of dilute sulphuric acid, a copious precipitate, 
 which partly consists of crystalline needles. If the drop 
 of reagent be allowed to slowly flow into the lead solution, 
 the precipitate generally consists of a mass of crystalline 
 needles, Plate V, fig. 3. 
 
 2. iToVo grain, yields a good precipitate, consisting principally 
 
 of needles and granules. 
 
 3. 5 J grain: an immediate, granular precipitate, and in a 
 
 little time, a quite fair deposit. 
 
 4. 10,000 grain: after a few moments, a cloudiness appears, 
 
 and in a little time, there is a very satisfactory, granular 
 deposit. 
 
 5. 20.00U grain, yields after a few moments, a slight cloudiness, 
 
 and after a little time, a satisfactory, granular precipitate. 
 If sulphate of potash be employed as the reagent, it pro- 
 duces the same results as the above. 
 
364 LEAD. 
 
 Free sulphuric acid, as well as soluble sulphates, also pro- 
 duce white precipitates in solutioas of baryta and strontia. 
 The sulphate of lead, however, is distinguished from that of 
 either of these metals, in that when moistened with sulphuret 
 of ammonium, it is turned black, due to the formation of sul- 
 phuret of lead. When sulphate of lead is intimately mixed 
 with carbonate of soda and heated before the blow-pipe flame, 
 on a charcoal support, it yields globules of metallic lead. 
 
 3. Hydrochloric Acid. 
 
 Hydrochloric acid and its soluble salts occasion in somewhat 
 strong solutions of salts of lead, a white precipitate of chloride 
 of lead (Pb CI), which is less soluble in diluted hydrochloric 
 and nitric acids than in pure water. When excess of chloride 
 of lead is digested, at the ordinary temperature, with pure 
 water for forty-eight hours, one part of the salt dissolves in 
 110 parts of the liquid; it is much more soluble in hot water. 
 It is readily soluble in concentrated hydrochloric acid. Chloride 
 of lead bears a strong heat without decomposition ; but at higher 
 temperatures, with a free supply of air, it is partially decom- 
 posed with the evolution of chlorine, and leaves a residue con- 
 sisting of a mixture of oxide and chloride of lead. 
 
 1. Yoo grain of oxide of lead, in one grain of water, yields, 
 
 with free hydrochloric acid, a copious, white, crystalline 
 precipitate, Plate V, fig. 4. 
 
 2. -s-oo" grain: in a very little time, a very fair deposit of 
 
 granules and crystalline needles. 
 
 3. ],Joo grain, yields after some minutes, a quite satisfactory 
 
 deposit of granules, needles, and prisms. 
 
 The results under 2 and 3 are obtained only when excess 
 of hydrochloric acid is employed. 
 
 This reagent, as well as soluble chlorides, also produce white 
 precipitates in solutions of silver and of salts of the suboxide 
 of mercury. The chlorides of silver and mercury, however, 
 are always thrown down in the amorphous form. The pre- 
 cipitated chloride of lead is insoluble, and unchanged in color, 
 by caustic ammonia ; whereas the silver precipitate is readily 
 
IODIDE OF POTASSIUM TEST. 365 
 
 soluble in. that alkali, whilst the mercury compound is turned 
 black. The action of ammonia, therefore, readily serves to 
 distinguish between the chlorides of these three metals. More- 
 over, the chloride of lead is readily soluble, especially by the 
 aid of heat, in large excess of water, whereas, on the other 
 hand, the silver and mercury compounds are wholly insoluble 
 in this liquid. 
 
 4. Iodide of Potassium. 
 
 This reagent produces in solutions of salts of lead, a bright 
 yellow precipitate of iodide of lead (Pbl), which is readily 
 soluble to a clear solution, in caustic potash, but almost wholly 
 insoluble even in very large excess of the precipitant ; under 
 the action of ammonia, it slowly assumes a white color. It 
 dissolves to a clear solution in strong hydrochloric acid; nitric 
 acid dissolves it to nitrate of lead. Heated before the blow- 
 pipe on charcoal, it turns reddish-yellow, then becomes brown- 
 ish, and finally volatilises. 
 
 Iodide of' lead is but sparingly soluble in cold water, but at 
 the boiling temperature, it dissolves more freely, and separates, 
 as the liquid cools, in beautiful, six-sided laminsjt We have 
 found, that when excess of the well-washed salt is digested in 
 pure water, with frequent agitation for twenty-four hours, at a 
 temperature ranging from 60° to 70° F., one part dissolves in 
 1,528 parts of the fluid. It is, however, much less soluble in 
 a dilute solution of iodide of potassium. This reagent, there- 
 fore, produces a copious precipitate from a pure saturated aque- 
 ous solution of the iodide of lead ; even in the presence of slight 
 excess of the reagent, a precipitate will form, when the lead- 
 iodide does not form more than the 10,000th part by weight 
 of the solution. The precipitate from a 1,000th solution of 
 oxide of lead, does not usually entirely dissolve by heating the 
 mixture to the boiling temperature. 
 
 1. xw grain of oxide of lead, in one grain of water, yields a 
 
 copious, bright yellow precipitate, which is usually partly 
 granular and crystalline. 
 
 2. iTo^i! grain, yields a very good deposit. 
 
366 LEAD. 
 
 3. 2","foo grain, yields a quite good precipitate, which readily 
 
 dissolves by heating the mixture to the boiling tempera- 
 ture, and again separates, as the liquid cools, in brilliant, 
 golden-yellow, six-sided plates, Plate V, fig. 5. 
 
 4. 57^00 grain: a very fair deposit. 
 
 5. iQ,^oo "o grain, yields an immediate, yellow precipitate, which 
 
 soon becomes a fair deposit. 
 
 6. 2 0,0 grain, yields, with a very small quantity of the re- 
 
 agent, after a little time, a quite satisfactory deposit of 
 
 granules and small plates. 
 The production, by this reagent, of a yeUow precipitate, 
 which is soluble in boiling water, and separates as the mixture 
 cools, in the form of six-sided plates, is characteristic of lead. 
 
 5. Ghromate of Potash. 
 
 Chromate and bichromate of potash throw down from solu- 
 tions of salts of lead, a bright yellow, amorphous precipitate of 
 chromate of lead (PbO, Cr O3), which is insoluble in acetic 
 acid, and only sparingly soluble in diluted nitric acid, but 
 readily soluble in caustic potash. Hydrochloric acid slowly 
 changes it to white chloride of lead; it is blackened by sulphu- 
 ret of ammonium. 
 
 1. 375-5- grain of oxide of lead, yields a copious precipitate. 
 
 2. Tro"oo grain: a very good deposit. 
 
 3. T o ,000 grain, yields a quite good, greenish-yellow precipitate. 
 
 4. 5- 0,000 grain, yields an immediate cloudiness, and in a few 
 
 minutes, a very satisfactory, greenish deposit. 
 O- ioo%o "o grain, yields after a little time, a greenish turbidity. 
 
 The formation of the deposit from dilute solutions, is facili- 
 tated by heating the mixture. 
 
 Chromate of potash produces in dilute neutral solutions of 
 salts of copper a yellowish precipitate, which after a time 
 assumes a reddish-brown color, and which, unlike the chromate 
 of lead, is readily soluble in acetic acid. The precipitate from 
 somewhat strong solutions of copper, has at once a reddish-brown 
 color. Bichromate of potash produces no precipitate from even 
 concentrated solutions of salts of copper. 
 
REACTIONS WITH THE ALKALIES. 367 
 
 6. Potash and Ammonia. 
 
 The caustic alkalies produce in solutions of salts of lead, a 
 white precipitate, consisting chiefly of the hydrated oxide of 
 lead, which is readily soluble in large excess of the fixed alka- 
 lies, insoluble in ammonia, and but sparingly soluble in nitrate 
 of ammonia. The precipitate is readily soluble in nitric acid; 
 and changed to chloride of lead by hydrochloric acid. Upon 
 the addition of sulphuretted hydrogen or sulphuret of ammonium, 
 the precipitate is changed to black sulphuret of lead. 
 
 From solutions of acetate of lead, ammonia causes only a 
 partial precipitate, due to the formation of tribasic acetate of 
 lead (3 PbO; C4H3O3), which remains in solution. 
 
 1. jtoTo grain of oxide of lead, yields with either of the fixed 
 
 alkalies, a copious, white, amorphous deposit. 
 
 2. i,Joo grain: a very good precipitate, which is readily solu- 
 
 ble in excess of the precipitant. 
 
 3. 10.000 grain, yields with a very small quantity of the re- 
 
 agent, a very satisfactory deposit. 
 These reagents also produce white precipitates with solutions 
 of several other metals, which in some instances, as with bis- 
 muth and tin, are, like the lead deposit, blackened by sulphuret 
 of ammonium. When, however, the dried lead precipitate is 
 heated on charcoal before the reducing flame of the blow-pipe, 
 it leaves malleable metallic globules, which are characteristic of 
 this metal. 
 
 7. Alkaline Carbonates. 
 
 The alkaline carbonates occasion in solutions of salts of lead, 
 a white amorphous precipitate of carbonate of lead, together 
 with more or less hydrated oxide of the metal. The precipitate 
 is almost wholly insoluble in excess of the precipitant, but 
 readily soluble in nitric and acetic acids, and changed to chlo- 
 ride of lead by hydrochloric acid; it is also readily soluble in 
 large excess of the fixed caustic alkalies. 
 
 1. 3-^-0 grain of oxide of lead, in one grain of water, yields a 
 copious precipitate. 
 
368 LEAD. 
 
 2. TTooo grain: a very good deposit. 
 
 3. To'.^o^o" grain: a very satisfactory precipitate. 
 
 4. 5 0,0 grain, yields within a few minutes, a quite distinct 
 
 cloudiness. 
 These reagents also produce white precipitates in solutions 
 of many other metals. But, from all these precipitates, the lead 
 compound is readily distinguished by its behavior before the 
 blow-pipe flame. 
 
 8. Oxalate of Ammonia. 
 
 Oxalate of ammonia produces in neutral solutions of salts of 
 lead, a white precipitate of oxalate of lead, which soon becomes 
 crystalline. The precipitate is readily soluble in nitric acid, 
 but insoluble in acetic acid, and blackened by sulphuret of 
 ammonium. 
 
 !• ToT" grain of oxide of lead, yields a copious precipitate, 
 which soon changes to a mass of long, crystallpe needles. 
 
 2- i.o'oo grain, yields a very good deposit, which soon changes 
 
 to granules and groups of needles. 
 
 3- 1 ,0 u "o grain, yields an immediate cloudiness, and after a 
 
 little time a quite distinct deposit. 
 4. s . grain, yields after some minutes, a quite satisfactory 
 
 turbidity. 
 When the oxalate of lead is heated before the blow-pipe on 
 a charcoal support, it yields globules of metallic lead. 
 
 9. Zinc Test. 
 
 When a drop of a solution of acetate of lead is placed in a 
 watch-glass, and a fragment of bright zinc added, the lead com- 
 pound is slowly decomposed with the deposition of metallic lead 
 upon the zinc, in the form of a brush-like, crystalline deposit. 
 If the lead solution be placed upon a piece of bright copper, 
 and the metal touched through the drop with a needle of zinc, 
 the lead deposits partly on the zinc and partly on the copper, 
 as a strongly adhering, grey deposit, over the space occupied 
 by the drop. 
 
SEPARATION FROM ORGANIC MIXTURES. 369 
 
 !• TW grain of oxide of lead, when placed in a watch-glass 
 and treated as just stated, yields a quite large, brush-like 
 deposit. 
 2. 1,0 grain : the zinc immediately darkens, and in a little 
 time, receives a quite satisfactory deposit. 
 A solution of tin yields with a fragment of zinc, a brush- 
 like deposit of metallic tin, which sometimes very closely re- 
 sembles that produced under similar conditions by lead. 
 
 Ferrocy.anide of potassium produces in solutions of salts of 
 lead a white amorphous precipitate of ferrocyanide of lead 
 (Pb2 Fe Cys), which is slowly soluble in large excess of nitric 
 acid, and changed to chloride of lead by hydrochloric acid. 
 One grain of a 1,000th solution of oxide of lead, yields with 
 this reagent, a quite good precipitate ; and the same quantity of 
 a 10,000th solution, gives after a little time, a quite satisfactory 
 deposit. 
 
 Ferricyanide of potassium throws down from solutions of 
 acetate of lead a dirty yellow precipitate, which is soluble in 
 nitric acid, decomposed by hydrochloric acid, and blackened by 
 sulphuret of ammonium. With one grain of a 1,000th solution 
 of oxide of lead, the reagent produces a quite good, amorphous 
 deposit 5 one grain of a 10,000th solution, yields after a few 
 minutes, a quite satisfactory, granular precipitate. 
 
 Both these reagents produce somewhat similar precipitates 
 in solutions of several other metals. 
 
 Sepaeation feom Oeganic Mixtuees. 
 
 Suspected. Solutions. — Various kinds of animal and vegetable 
 substances more or less decompose and precipitate acetate of 
 lead, when in solution ; but most of these precipitates are readily 
 soluble in diluted nitric acid. When a mixture, of this kind is 
 presented for examination, it should be acidulated with nitric 
 acid and heated for some time, then allowed to cool, the liquid 
 filtered, and the solids upon the filter washed, the washings 
 being collected with the original filtrate, and the solids reserved. 
 The filtrate, after concentration if necessary, is then saturated 
 
 24 
 
370 LEAD. 
 
 with sulphuretted hydrogen gas, and the mixture allowed to 
 stand in a moderately warm place for some time ; any precipi- 
 tate thus produced, is collected on a small filter, washed, and 
 while stiU moist, washed from the filter into a test-tube or any 
 convenient vessel, by means of a jet of water from a wash- 
 bottle. 
 
 When the precipitate has completely subsided, most of the 
 supernatant fluid is decanted, and the solid residue dissolved, 
 by the aid of a gentle heat, in the least possible quantity of 
 nitric acid, added drop by drop. By this means, any sulphuret 
 of lead present will be converted into nitrate of lead, while the 
 sulphur set free will remain unoxidised. The mixture is now 
 diluted somewhat with pure water, the liquid filtered, and a 
 portion of the filtrate tested with a solution of chromate of 
 potash. Other portions of the filtrate may be examined by any 
 of the other tests already pointed out. 
 
 The sulphuret of lead precipitated from the 1,000th of a 
 grain of oxide of lead, when diffused in ten grains of water 
 and heated with one drop of nitric acid, yields a clear solu- 
 tion, which gives with reagents about the same reactions as a 
 10,000th solution of lead-oxide. If large excess of nitric acid 
 has been used for dissolving the sulphuret of lead, the filtered 
 liquid should be carefully neutralised by pure caustic potash, 
 before the application of any of the tests. 
 
 It would rarely, if ever, happen with organic mixtures of 
 this kind containing lead, that the metal would entirely escape 
 solution in diluted nitric acid. If, however, there has been a 
 failure to detect the metal, by the above method, the solids 
 obtained by filtration from the original mixture, may be boiled 
 for some time with water containing about one-sixth of its vol- 
 ume of nitric acid, the solution filtered, the filtrate evaporated 
 to dryness, and the residue incinerated. This residue is treated 
 with a little nitric acid, the solution diluted with a small quan- 
 tity of water, then filtered, and the filtrate neutralised and tested 
 in the ordinary manner. 
 
 Contents of the Stomach. — These, after the addition of water 
 if necessary, may be acidulated with nitric acid, and examined 
 in the manner just described for suspected solutions. 
 
SEPARATION FROM THE TISSUES. 371 
 
 If an alkaline sulphate had been administered as an anti- 
 dote, the poison may be in the form of insoluble sulphate of lead. 
 Under these circumstances, the contents of the stomach should 
 be carefully examined, and any white powder found, collected 
 and washed, then boiled with a strong solution of pure caustic 
 potash, and the lead precipitated by sulphuretted hydrogen. 
 Or, any sulphate of lead obtained, may be placed in a wide test- 
 tube and agitated occasionally for several hours with a strong 
 solution of bicarbonate of soda, the clear liquid decanted and the 
 operation repeated with a fresh portion of the soda solution. 
 By this means, the lead-sulphate will be converted into insoluble 
 carbonate of lead. This is washed, then dissolved in a little 
 acetic acid or in very dilute nitric acid, and the solution tested. 
 
 According to the observations of Orfila, in acute poisoning 
 by the salts of lead, the villous coat of the stomach frequently 
 presents numerous white points which contain lead, and which 
 are blackened by sulphuretted hydrogen. 
 
 From the Tissues. — The solid organ, such as a portion of the 
 liver, is cut into small pieces, and boiled in a porcelain dish 
 with nitric acid, diluted with about four parts of water, until the 
 mixture becomes homogeneous. When the mixture has cooled, 
 the liquid is filtered, the filtrate evaporated to dryness, the resi- 
 due moistened with nitric acid, again evaporated to dryness, 
 and the heat continued until all vapors cease to be evolved and 
 the residue becomes a carbonaceous mass. The mass thus ob- 
 tained, is pulverised and boiled with a small quantity of strong 
 nitric acid, the mixture diluted with water, the solution filtered, 
 the filtrate evaporated to dryness, and the residue dissolved in 
 a small quantity of water slightly acidulated with nitric acid. 
 This solution, after filtration if necessary, is saturated with sul- 
 phuretted hydrogen gas, and allowed to stand until the precipi- 
 tate has completely subsided. Any sulphuret of lead thus 
 deposited, is collected on a small filter, washed, then suspended 
 in a small quantity of water and dissolved, by the aid of heat, 
 in the least possible quantity of nitric acid, and the solution 
 tested in the usual manner. 
 
 If the quantity of sulphuret of lead, precipitated by the 
 sulphuretted gas,, is too minute to be separated from the filter, 
 
372 LEAD. 
 
 the filter or that portion of it containing the deposit, may be 
 heated with sufficient dilute nitric' acid to dissolve the precipi- 
 tate ; the solution is then filtered, neutralised, and tested. 
 
 From the observations of several experimentalists, it appears 
 that absorbed lead is very slowly eKminated from the system. 
 Orfila states (Toxicologic, i, p. 858), that when dogs were given 
 about eight grains of acetate of lead daily for one month, the 
 metal was found in the liver and brain of the animals when 
 killed one hundred and four days after they had ceased to take 
 the poison. According to this observer, the metal is eliminated 
 from the body principally with the urine. 
 
 From the Urine. — Fifteen or twenty ounces of the urine, 
 acidulated with nitric acid, may be evaporated to dryness, the 
 residue carbonised by nitric acid, and the carbonaceous mass 
 treated in the manner just described for the separation of the 
 metal from the tissues. By following this method, we detected 
 the metal in notable quantity in the urine almost daily for about 
 two weeks, in two instances of severe chronic lead-poisoning, 
 resulting from the use of water collected in a leaden cistern. 
 Of eight persons who used this water, only two of them were 
 affected by it, and these the elder members of the family. 
 
 Kletzinsky proposes, after rendering the urine alkaline by 
 caustic potash, to add about two per cent, of its weight of 
 nitrate of potash and evaporate to dryness. The residue is 
 then exposed to a dull red heat, whereby the whole of the or- 
 ganic matter is destroyed. The cooled mass is powdered and 
 boiled for some time with a half saturated solution of neutral 
 tartrate of ammonia, to which some caustic ammonia has been 
 added, the solution filtered, the filtrate acidulated with hydro- 
 chloric acid, and then precipitated by sulphuretted hydrogen. 
 The precipitate is allowed twenty-four hours to subside, then 
 washed, redissolved in warm dilute nitric acid, the solution fil- 
 tered, neutralised, and tested in the usual manner. (Thudichum 
 On the Urine, p. 406.) 
 
 Quantitative Analysis. — Lead may be very accurately 
 estimated in the form of sulphuret of the metal. The solution, 
 very slightly acidulated with nitric acid, is treated with a slow 
 
COPPER: CHEMICAL NATURE. 373 
 
 stream of washed sulphuretted hydrogen gas, as long as a pre- 
 cipitate is produced, and the mixture then allowed to stand in 
 a moderately warm place, until the precipitate has completely 
 deposited. The precipitate is then collected on a filter of known 
 weight, washed, thoroughly dried on a water-bath, and weighed. 
 One hundred parts by weight of the dried sulphuret, correspond 
 to 93"31 parts of oxide of lead, or 158'37 parts of pure crys- 
 tallised acetate of lead. 
 
 When the lead exists in the form of sulphate, this may be 
 washed with water containing a little alcohol, dried at 212° F., 
 and weighed. One hundred parts by weight of the dried sul- 
 phate, correspond to one hundred and twenty-five parts of crys- 
 tallised acetate of lead. 
 
 Section II. — Copper. 
 
 History and Chemical Nature. — Copper is represented by 
 the symbol Cu ; its combining equivalent is 31'68, and its spe- 
 cific gravity 8"95. This metal is frequently found in its uncom- 
 bined state in nature ; its most common ore is copper-pyrites, 
 which consists of a mixture of the sulphurets of copper and 
 iron. According to Walchner, copper is as widely distributed 
 in nature as iron. In some mineral waters it is said to exist to 
 the extent of half a grain to the gallon of water. (See Liebig 
 and Kopp's Annual Report, vol. ii, p. 268.) It is also found in 
 sea-water and in sea-weeds. Sarzeau states that he found it in 
 minute quantity in various vegetable substances, such as coffee, 
 sugar, wheat, and flour ; and several observers state, that they 
 detected traces of it in the blood and various organs of the 
 healthy human body. On the other hand, equally reliable ob- 
 servers have failed to detect a trace of the metal, either in 
 articles of ordinary food, or in the healthy human body. 
 
 Copper, in its uncombined state, is a rather hard, quite 
 tough, ductile metal, of a peculiar red color, and a somewhat 
 granular fracture ; its fusing point, according to Daniell, is about 
 2,000° F. When exposed to moist air, it slowly absorbs oxy- 
 gen and carbonic acid, with the formation of a green coating of 
 
374 COPPER. 
 
 subcarbonate of copper, known also as natural verdigris. Im- 
 mersed in pure water, copper undergoes little or no change ; 
 but in water containing common salt, it slowly becomes covered 
 with a layer of oxychloride of the metal. In water containing 
 an organic acid, as vinegar, or when certain kinds of fatty mat- 
 ters are present, the metal is more readily acted upon. Nitric 
 acid rapidly dissolves it, with the evolution of binoxide of nitro- 
 gen and the formation of nitrate of oxide of copper. Cold sul- 
 phuric acid has no direct action upon the metal ; but the hot 
 acid readily dissolves it, with the evolution of sulphurous acid 
 gas, to sulphate of copper. Hydrochloric acid, even at the 
 boiling temperature, fails to act upon the metal. 
 
 Combinations. — Copper readily unites with most of the metal- 
 loids. With oxygen, it unites in two proportions, forming the 
 protoxide (CuO), and the suboxide (CujO), the former of which 
 has a black, and the latter a red color. In its hydrated state, 
 the protoxide has a blue color ; the color of the hydrated sub- 
 oxide is yellow. The protoxide of copper readily unites with 
 acids forming salts, which in their hydrated state have either a 
 blue or green color, and several of which are freely soluble in 
 water. The suboxide forms but few salts, and these are exceed- 
 ringly unstable. The most important compounds of copper, in 
 regard to their medico-legal relations, are the sulphate, and the 
 subacetate, or verdigris. , 
 
 Sulphate of copper, or hlue vitriol, in its crystallised state, 
 consists of one equivalent of protoxide of copper, one of sul- 
 phuric acid, and five equivalents of water (CuO, SO3, 5 Aq). 
 In this state, it forms large, blue crystals, which have a nause- 
 ous, metallic taste, and a density of 2'27. It is soluble in about 
 four times its weight of water at the ordinary temperature, and 
 in about two parts of boiling water: the solution has a blue 
 color, and a distinctly acid reaction. At a temperature of about 
 400°, the salt becomes anhydrous and crumbles to a nearly white 
 powder ; at a strong red heat, it undergoes decomposition, evolv- 
 ing oxygen and sulphurous acid gas, and leaving a residue of 
 protoxide of copper. 
 
 Verdigris, as found in the shops, is a mixture in variable 
 proportions of the lower acetates of copper, having either a blue 
 
PHYSIOLOGICAL EFFECTS. 375 
 
 or green color, and a disagreeable acetous odor. It is usually 
 met with in the form of hard, irregular masses, but sometimes 
 as a fine powder. Under the action of water, verdigris is only 
 partly dissolved, a greenish residue of tribasic acetate of copper 
 being left. It is completely soluble in water containing a little 
 free hydrochloric or nitric acid. Sulphuric acid readily decom- 
 poses it, with the formation of sulphate of copper, and the 
 elimination of acetic acid. 
 
 Physiological Effects. — When swallowed in its metallic state, 
 copper seems to be entirely inert, at least so long as it retains 
 its metallic form ; should, however, the metal become oxidised, 
 within the alimentary canal, it may give rise to severe symp- 
 toms. In a case, quoted by Dr. Beck, in which six copper 
 penny-pieces were swallowed, and retained in the body for five 
 years, no inconvenience was experienced, except the effects of 
 mechanical obstruction. On the other hand, a case is related 
 by Dr. Jackson, of Boston, in which a copper half-cent, swal- 
 lowed by a child, produced nausea and vomiting, with other 
 symptoms of copper poisoning. 
 
 The compounds of copper, when taken in large doses, or in 
 frequently repeated small doses, are all more or less poisonous. 
 Even some of the compounds that are insoluble in water, are 
 capable of producing very active effects. The preparations of 
 this metal have been rarely administered for criminal purposes; 
 but numerous instances are recorded of accidental poisoning by 
 some of them, resulting from the use of food prepared in cop- 
 per vessels. 
 
 Symptoms. — The usual effects produced by the preparations 
 of copper, when swallowed in poisonous quantity, are a coppery 
 taste in the mouth, nausea, a sense of burning heat in the mouth 
 and throat, eructations, severe headache, violent vomiting, with 
 more or less purging, and acute pain throughout the stomach 
 and bowels. The pulse becomes small, frequent, and irregular; 
 and there may be great dizziness, difficulty of breathing, great 
 anxiety, cold sweats, extreme thirst, cramps in the extremities, 
 scantiness or entire suppression of urine, and death is sometimes 
 preceded by convulsions and insensibility. Among the symp- 
 toms occasionally present, is jaundice, which, according to Dr. 
 
376 COPPER. 
 
 Christison, is never observed either in arsenical or corrosive 
 sublimate poisoning. 
 
 When taken in frequently repeated small doses, the prepara- 
 tions of copper produce much the same symptoms as those just 
 described. There is loss of appetite ; a coppery taste in the 
 mouth ; nausea, with frequent efforts to vomit ; violent head- 
 ache ; irregular and frequent pulse ; hot skin ; impaired respira- 
 tion ; great thirst ; extreme debility ; sharp, shooting pains in 
 the stomach, with tension and tenderness of the abdomen ; fre- 
 quent purging, the discharges being usually dark colored, and 
 their passage attended with pain ; and there is more or less 
 alteration of the color of the skin. 
 
 A not unfrequent cause of slow poisoning by copper, as 
 already intimated, is the use of utensils of the metal for the 
 preparation of food. The risk of contamination in these cases, 
 is always much increased by the free action of the atmosphere, 
 and by allowing the food to cool and remain in contact with the 
 vessel. By employing bright vessels, and removing the food as 
 soon as prepared, there is little danger in the use of the metal, 
 for such purposes. 
 
 Period when Fatal. — The time at which death has taken 
 place, in acute poisoning by copper, has been subject to con- 
 siderable variation. In the case of a young lady, mentioned by 
 Dr. Percival, death occurred on the ninth day. In this case, 
 the poisoning resulted from the eating of pickles contaminated 
 with copper. The symptoms were, sharp pains in the stomach, 
 an eruption over the breast, general shooting pains, thirst, a 
 small, frequent pulse, vomiting, hiccough, and purging: there 
 was neither stupor nor convulsions. In a case related by Pyl, 
 two ounces of verdigris proved fatal in three days, to a woman. 
 In another instance, quoted by Dr. Christison, a lady and her 
 daughter were poisoned by sour-krout, which had been kept 
 in a copper vessel. They were soon seized with pain in 
 the stomach, then nausea and vomiting, followed by purging, 
 convulsions, and insensibility. The daughter died in twelve 
 hours, and the mother an hour later. (On Poisons, p. 362.) 
 A child, aged sixteen months, swallowed an unknown quantity 
 of solid sidphate of copper, and died from its effects four hours 
 
ANTIDOTES. 377 
 
 afterwards. This is, perhaps, the most rapidly fatal case yet 
 recorded. 
 
 Fatal Quantity. — In a case quoted by Dr. Beck, one ounce 
 of sulphate of copper, taken with suicidal intent, by a man aged 
 forty years, proved fatal within twelve hours. (Med. Jur., vol. 
 ii, p. 667.) In another instance, seven drachms of the same 
 salt, with three drachms of sulphate of iron, caused the death 
 of an adult, in three days. Dr. Percival states, that the most 
 violent convulsions he ever witnessed, were produced in a young 
 woman, by two drachms of blue vitriol : under appropriate 
 treatment, she recovered. In a case cited by Dr. Taylor, half 
 an ounce of verdigris destroyed the life of a woman, in sixty 
 hours ; and in another, about twenty grains of the subchloride 
 of copper, caused the death of a child. (On Poisons, p. 524.) 
 On the other hand, in a case quoted by Dr. A. Stille (Mat. 
 Med., vol. i, p. 325), in which an ounce of blue vitriol had 
 been swallowed with suicidal intent, complete recovery took 
 place, although the patient refused to take an emetic. 
 
 Teeatment. — In acute poisoning by any of the preparations 
 of copper, the vomiting should be encouraged by the free ad- 
 ministration of demulcent liquids ; or the stomach may be emp- 
 tied by means of the stomach-pump. As a chemical antidote, 
 albumen in large excess was strongly advised by Orfila. The 
 white of egg should be freely given, and its exhibition followed 
 by large draughts of tepid water. An excess of albumen read- 
 ily decomposes the soluble salts of copper, with the formation 
 of albuminate of copper, which is said to be but sparingly sol- 
 .uble in the juices of the stomach. 
 
 According to recent experiments by Dr. Schrader, of Got- 
 tingen, milk is equally efficient with albumen, as an antidote. 
 The caseate of copper thus produced, should be speedily re- 
 moved from the stomach, by vomiting. (Amer. Jour. Med. Sci., 
 Oct., 1855, p. 540.) M. Duval strongly advised the use of 
 sugar ; but it is very questionable whether this substance can 
 be regarded as an antidote : it might, however, be administered 
 in connection with albumen or milk. 
 
 Among the other substances that have been proposed as an- 
 tidotes, may be mentioned ferrocyanide of potassium, iron filings. 
 
378 COPPER. 
 
 calcined magnesia, and hydrated sulphuret of iron. The em- 
 ployment of the alkaline sulphurets, and also of vinegar, would 
 be inadmissible. 
 
 Post-mortem Appearances. — The morbid appearances, in 
 poisoning by the preparations of copper, are usually confined to 
 the alimentary canal. In acute cases, the inside of the stomach" 
 and of the intestines not unfrequently present a bluish or green- 
 ish appearance, due to the presence of the poisonous compound. 
 It should be remembered, however, as first pointed out by 
 Orfila, that a somewhat similar appearance may result from the 
 presence of altered bile. The lining membrane of the stomach 
 is usually inflamed and softened ; and in some few instances it 
 presented an ulcerated, and even gangrenous appearance. Sim- 
 ilar appearances have been found in the intestines ; in some few 
 cases, the intestines were found perforated, and their contents 
 had partially escaped into the cavity of the abdomen. 
 
 In the fatal case cited by Dr. Beck, the oesophagus was 
 foimd of a livid-red color, and the stomach of a bluish hue, 
 which coidd be removed by washing ; under this, the mucous 
 membrane was of a deep red color. The intestinal tube, through- 
 out its whole extent, was highly inflamed. In the case before 
 referred to, in which seven drachms of the sulphate of copper, 
 together with three drachms of green vitriol, had been taken, 
 the mucous membrane throughout the stomach and intestines 
 was found in a perfectly healthy condition. 
 
 Chemical Properties. 
 
 In the solid state. — The general chemical nature and 
 properties of the sulphate and subacetates of copper, or verdi- 
 gris, have already been pointed out. The nitrate of copper 
 has a beautiful blue color, and is freely soluble in water. The 
 carbonates of the metal have either a blue or green color ; these 
 salts are insoluble in water, but readily soluble in diluted acids, 
 with effervescence. With chlorine, the metal iinites in two pro- 
 portions, forming the subchloride and the protochloride ; the 
 former of which is white and insoluble, while the latter has a 
 green color, and is readily soluble. 
 
SULPHURETTED HYDROGEN TEST. 379 
 
 The property of forming blue and green compounds is some- 
 what peculiar to copper ; yet some of the preparations of a few 
 other metals have one or the other of these colors. Thus, some 
 of the compounds of nickel, sesquioxide of chromium, and pro- 
 toxide of uranium are green, while some of the salts of cobalt 
 are blue. Copper, however, is the only one of these metals 
 likely to be met with in medico-legal investigations, and is 
 readily distinguished from the others in that when its salts are 
 moistened with a diluted acid and placed in contact with a piece 
 of bright iron or steel, they impart to the iron a coating of me- 
 tallic copper, readily recognised by its peculiar red color. 
 
 Salts of copper, when heated in the inner blow-pipe flame, 
 impart a beautiful green coloration to the outer flame. When 
 mixed with dry carbonate of soda or cyanide of potassium and 
 heated on a charcoal support, in the reducing blow-pipe flame, 
 they yield red particles of metallic copper. 
 
 Of Solutions of Copper. — The soluble salts of copper 
 communicate their color to solutions, even when highly diluted. 
 In the case of the sulphate, the blue color is quite perceptible 
 in fifty grains of a solution containing only the 1,000th part of 
 its weight of oxide of copper; the same quantity of a 5,000th 
 solution, exhibits a slight bluish tint. In larger quantities of 
 the liquid, the color of this salt is quite perceptible, in solutions 
 much more dilute than those just mentioned. Solutions of salts 
 of copper, when not too dilute, slightly redden blue litmus- 
 paper ; they have an astringent, metaUic taste, and when evap- 
 orated spontaneously, leave the salt in its crystalline state. 
 
 In the following investigations of the different tests for cop- 
 per, when in solution, pure aqueous solutions of the sulphate 
 were employed. The fractions indicate the quantity of protox- 
 ide of copper (CuO) present in one grain of the solution. One 
 part of the protoxide corresponds to 3" 142 parts of pure crys- 
 tallised sulphate of copper. 
 
 1. Sulphuretted Hydrogen. 
 
 Sulphuretted hydrogen gas and the alkaline sulphurets throw 
 down from solutions of salts of copper, even in the presence of 
 
380 COPPER. 
 
 a free acid, a precipitate of sulphuret of copper (CuS), which 
 as first produced has a brown color, but sooner or later becomes 
 bi'ownish or greenish-black. The precipitate is slightly soluble 
 in large excess of sulphuret of ammonium, but insoluble in the 
 fixed alkaline sulphurets, and in the caustic alkalies. It is only 
 sparingly soluble in cold concentrated nitric acid ; but upon the 
 application of heat, even when the acid is somewhat dilute, it 
 readily dissolves, forming a blue solution of the nitrate, with 
 more or less sulphate of copper. It is slowly dissolved by hot 
 concentrated hydrochloric acid, with the formation of subchlo- 
 ride of copper ; concentrated sulphuric acid has but little action 
 upon it in the cold, but it is decomposed by the hot acid. In 
 its dry state, sulphuret of copper has a greenish-black color ; 
 when exposed to moist air, it slowly absorbs oxygen, and be- 
 comes converted into sulphate of copper. 
 
 In examining the limit of this test, ten grains of the copper 
 solution were submitted to a slow stream of the washed sulphu- 
 retted gas. 
 
 1. 100th solution of oxide of copper (=to grain CuO), yields 
 
 an immediate, deep brown precipitate, which soon becomes 
 brownish-black. After standing some time, the precipitate 
 entirely separates as a copious, black deposit, leaving the 
 solution perfectly colorless. 
 
 2. 1,000th solution, yields at first a brown mixture, from which 
 
 after a time, a brownish-black deposit separates, leaving 
 the liquid of a brownish color. After standing some hours, 
 the liquid becomes colorless, and the deposit acquires a 
 greenish-black color. 
 
 3. 5,000th solution : the solution immediately assumes a brown 
 
 color, and soon becomes turbid ; after several hours, a 
 quite fair, greenish-black deposit separates. 
 
 4. 10,000th solution : the liquid immediately acquires a brown- 
 
 ish color, which soon deepens ; after the mixture has 
 stood about twenty-four hours, it yields a greenish-brown 
 deposit. 
 
 5. 25,000th solution : the liquid immediately assumes a yellow 
 
 brown color, which soon changes to brown ; in twenty- 
 four hours, a satisfactory, light brown deposit has formed. 
 
AMMONIA TEST. 381 
 
 6. 50,000th solution : almost immediately the liquid assumes 
 
 a yellowish color, and soon becomes brownish-yellow ; in 
 twenty-four hours, quite perceptible brownish flakes have 
 separated, and the liquid has a brownish color. 
 
 7. 100,000th solution : after several minutes, the liquid acquires 
 
 a faint yellowish color, which soon becomes quite distinct; 
 
 in twenty-four hours, it has a faint brownish hue, but there 
 
 is no precipitate. 
 This reagent also produces brownish precipitates with sev- 
 eral other metals, but most of these are extremely rare and 
 would never be met with in medico-legal investigations. The 
 transition of color observed in the sulphuret of copper is some- 
 what peculiar to this substance, especially when the metal is 
 present in quite notable quantity. When the sulphuret of cop- 
 per is moistened with hydrochloric acid and touched for a little 
 time with a bright sewing needle, the latter becomes coated 
 with metallic copper, of its peculiar color. The true nature of 
 the precipitate may also be established by dissolving it, by the 
 aid of heat, in a little nitric acid, evaporating the solution to 
 dryness, dissolving the residue in a little water, and testing the 
 solution with ammonia or ferrocyanide of potassium, in the 
 manner described hereafter. 
 
 Neither nickel, chromium, uranium, nor cobalt — metals which 
 like copper have the property of forming green or blue salts — 
 will yield a precipitate from acid or neutral solutions, when 
 treated with sulphuretted hydrogen gas. 
 
 2. Ammonia. 
 
 This reagent produces in solutions of salts of copper a blue 
 or greenish-blue, amorphous precipitate, which is readily soluble, 
 to a deep blue solution, in excess of the precipitant. With very 
 dilute cupreous solutions, the reagent may fail to produce a pre- 
 cipitate, but the liquid immediately assumes a blue color, which 
 is readily destroyed upon the addition of a free acid. 
 1. y^o^ grain of oxide of copper, in one grain of fluid, yields a 
 copious precipitate, which with excess of the reagent dis- 
 solves to an intensely blue solution. 
 
382 COPPER. 
 
 2. i,Joo grain, yields a blue, flocculent deposit, which readily 
 
 dissolves in excess, forming a distinctly blue liquid. 
 
 3. sTToo grain, with a very minute quantity of the reagent, 
 
 yields a very distinct precipitate : this precipitate is best 
 obtained by exposing the copper solution to the vapor of 
 ammonia; when the precipitate is dissolved in excess of 
 the reagent, the mixture has a just perceptible blue tint. 
 
 4. 10.0 grain, when exposed to the vapor of ammonia, yields 
 
 a distinct precipitate, which when dissolved in excess of 
 the precipitant, forms an apparently colorless liquid. Ten 
 grains of the solution, have a quite distinct blue color. 
 This blue color is quite obvious in much more dilute solu- 
 tions, when larger quantities of the liquid are examined. 
 Normal solutions of salts of nickel, yield with ammonia a 
 partial precipitate of green, hydrated oxide of nickel, which is 
 readily soluble iu excess of the reagent, forming a deep blue 
 Solution. Cobalt yields with the reagent, a blue precipitate, 
 which dissolves ia excess of the precipitant, forming a reddish- 
 brown liquid. Sesquioxide of chromium solutions yield a bluish- 
 green deposit, slightly soluble in excess of the reagent, with the 
 formation of a pink solution. Salts of uranium yield with the 
 reagent, a yellow precipitate, which is insoluble in excess of 
 the precipitant. 
 
 3. Potash and Soda. 
 
 The fixed caustic alkalies throw down from solutions of salts 
 of copper, a ^ blue amorphous precipitate of hydrated oxide of 
 copper (CuO, HO), which is insoluble in excess of the precipi- 
 tant, but readily soluble in acids, even acetic acid. On boiling 
 the mixture containing an excess of the reagent, the precipitate 
 speedily becomes anhydrous and of a black color ; this change 
 is slowly effected even at ordinary temperatures. 
 
 The reaction of these reagents is much modified by the 
 presence of certain organic substances. Thus, in a solution of 
 the sulphate of copper containing grape-sugar, the precipitate 
 is readily soluble in excess of the precipitant, forming a deep 
 blue solution, from which the whole of the copper is thrown 
 
FERROCYANIDE OF POTASSIUM TEST. 383 
 
 down by boiling, in the form of a yellow or red powder of the 
 suboxide of copper. In the presence of tartaric acid, the re- 
 agent may fail to produce a precipitate, even upon boiling the 
 mixture. 
 
 !• TcTo grain of oxide of copper, in one grain of water, yields 
 a copious, blue, gelatinous deposit. 
 
 2. i.Joo grain : a very good, flocculent precipitate. 
 
 3. 5,00 grain, yields, in a very little time, a slight, flocculent 
 
 precipitate, which soon becomes a quite fair deposit. 
 
 4. 10,0 grain : after a little time, a just perceptible cloudi- 
 
 ness, and soon a quite distinct, flaky deposit. 
 
 These reagents also produce a blue precipitate in solutions 
 of salts of cobalt, which is insoluble in excess of the reagent ; 
 but when this mixture is boiled, the precipitate is changed into 
 a brownish or reddish deposit. Solutions of the sesquioxide of 
 chromium yield with the reagent a bluish-green precipitate, 
 readily soluble in excess of the precipitant, forming a greenish 
 liquid, from which, by continued boiling, the whole of the chro- 
 mium is reprecipitated, as green, hydrated sesquioxide of the 
 metal. These are the only two metals which yield with these 
 reagents precipitates, the color of which might be confounded 
 with that of the copper precipitate. 
 
 Carbonate of potash and of soda occasion in aqueous solu- 
 tions of cupreous salts, a greenish-blue, amorphous precipitate 
 of hydrated subcarbonate of copper, which is sparingly soluble, 
 to a bluish Hquid, in excess of the precipitant. If an excess of 
 the reagent be added and the mixture boiled, the precipitate 
 becomes converted into anhydrous black oxide of copper. The 
 limit of the reaction of these reagents, is the same as that of 
 the fixed caustic alkalies. 
 
 4. Ferrocyanide of Potassium. 
 
 This reagent throws down from somewhat strong solutions of 
 salts of copper, a reddish-brown, amorphous precipitate of ferro- 
 cyanide of copper (Cu2 FeCya), which is insoluble in excess of 
 the precipitant, and in acetic and hydrochloric acids, but spar- 
 ingly soluble in ammonia to a bluish-green liquid, from which 
 
384 COPPER. 
 
 it is reprecipitated by excess of acetic acid. From more dilute 
 solutions, the reagent produces a purple precipitate ; while from 
 still more dilute solutions, it fails to produce a precipitate, but 
 the mixture assumes a reddish color. 
 
 !• TTo grain of oxide of copper, yields a copious, reddish-brown, 
 gelatinous precipitate. 
 
 2. iToo'o grain : an immediate purple precipitate, which soon 
 
 becomes a quite good, reddish-brown deposit. 
 
 3. 10,000 grain : a reddish, flocculent turbidity. 
 
 4. 2 5,000 grain, yields a slight cloudiness ; when viewed over 
 
 white paper, the mixture exhibits a distinct reddish color. 
 
 When_^t;e grains of a 100,000th solution are treated with a 
 small quantity of the reagent, the mixture presents a quite dis- 
 tinct reddish color. This color is readily observed even in more 
 dilute solutions, when larger quantities are examined. 
 
 Ferrocyanide of pota'Ssium, also produces in solutions of 
 persalts of uranium, a precipitate very similar in color to that 
 of the ferrocyanide of copper. But the uranium precipitate is 
 changed to a yellow compound upon the addition of excess of 
 ammonia ; whereas, as before stated, the ferrocyanide of copper 
 is soluble to a limited extent in excess of this alkaU, yielding a 
 bluish-green liquid. Moreover, solutions of copper are readily 
 distinguished from those of uranium, by their behavior with 
 sulphuretted hydrogen, and ammonia, as already pointed out. ' 
 Copper and uranium are the only metals that yield reddish- 
 brown precipitates with ferrocyanide of potassium. 
 
 The reaction of this reagent, with solutions of cupreous salts, 
 is much modified by the presence of even minute quantities of 
 iron, with which it produces a blue precipitate. 
 
 5. Iron Test. 
 
 When a piece of bright iron or steel is immersed in a solu- 
 tion of a salt of copper, it sooner or later decomposes the salt 
 and receives a coating of metallic copper, having the charac- 
 teristic color of the metal; at the same time, a salt of iron, 
 containing the acid previously combined with the copper, is 
 formed. This reaction, esp'ecially from dilute solutions, is much 
 
PLATINUM AND ZINC TEST. 385 
 
 facilitated by the presence of a little free sulpturic or hydro- 
 chloric acid. 
 
 In examining the limit of this test, a single grain of the 
 copper solution, placed in a watch-glass, was acidulated with 
 sulphuric acid, and a small portion of a bright sewing needle 
 introduced into the mixture ; in the very dilute sokitions, the 
 length of the needle did not exceed the yV of an inch. It is 
 obvious, that the thickness of the deposit from a given' quantity 
 of copper, and consequently the delicacy of th(J test, will de- 
 pend very much upon the extent of surface over which the 
 metal is distributed. 
 
 1. YoT grain of oxide of copper, yields a very fine coating. 
 
 2. iT^oT) grain : in a little time, the needle acquires a very sat- 
 
 isfactory deposit. 
 
 3. 10,000 grain : in a few minutes, the needle presents a red- 
 
 dish tint, and in fifteen minutes, receives a satisfactory 
 coating. 
 
 4. 2in^"oTJ grain : after several minutes, the needle exhibits a 
 
 just perceptible reddish hue, which improves, and after an 
 hour, becomes perfectly satisfactory. 
 
 By allowing the needle to remain in the acidulated liquid 
 for several hours, satisfactory deposits may be obtained from 
 solutions much more dilute than the last-mentioned. The true 
 color of very thin deposits, is best determined by the aid of a 
 hand-lens. 
 
 It need hardly be remarked that this reaction is peculiar to 
 copper. The cupreous nature of the deposit may be shown, by 
 dissolving out the iron, from the coated needle, with diluted 
 sulphuric acid, and then dissolving the washed coating in a 
 little nitric acid, evaporating the solution to dryness, redissolv- 
 ing the residue in a few drops of water, and testing the liquid 
 with ferrocyanide of potassium. 
 
 6. Platinum and Zinc Test. 
 
 When a solution of a salt of copper is acidulated with hy- 
 drochloric or sulphuric acid, and placed in a platinum dish, 
 and then a fragment of bright zinc placed in the liquid, the 
 
 25 
 
386 COPPER. 
 
 cupreous compound quickly undergoes decomposition with the 
 deposition of a coating of metallic copper, of its peculiar color, 
 upon the platinum covered by the liquid. 
 
 !• To^ grain of oxide of copper, in one grain of fluid, when 
 treated after this method, yields a very fine deposit. 
 
 2. t;o"o"o grain : after a few minutes, the platinum exhibits a 
 
 very satisfactory coating. 
 
 3. t:o"6"o grain : after several minutes, there is a quite distinct 
 
 deposit. ' 
 This method will not serve for the detection of as minute 
 quantities of copper as the iron test, since in its application the 
 metal is distributed over a larger surface than when the iron- 
 method is employed. If the washed deposit be moistened with 
 a few drops of caustic ammonia, the liquid slowly acquires a 
 blue color, due to the formation of a soluble compound of the 
 metal. 
 
 7. Arsenite of Potash. 
 
 This reagent throws down from neutral solutions of salts of 
 copper, when not too dilute, a bright green precipitate of arsen- 
 ite of copper (2 CuO ; AsOs), known also as Scheele's green. 
 This precipitate is readily soluble in ammonia and in free acids. 
 !• Too" grain of oxide of copper, in one grain of water, yields 
 a copious precipitate. 
 
 2. iToVo grain : a quite good, yellowish-green deposit. 
 
 3. 10,000 grain : after a little time, the mixture becomes decid- 
 
 edly turbid ; but the green color is not perceptible. With 
 larger quantities of the solution, the reagent produces sat- 
 isfactory results, even in much more dilute solutions. 
 The production of a bright green precipitate by this reagent 
 is quite characteristic of copper. However, solutions of salts 
 of nickel yield with the reagent, a pale green deposit, which, 
 like the copper precipitate, is readily soluble in ammonia and in 
 acetic acid. 
 
 8. Chromate of Potash. 
 
 Protochromate of potash, when added in excess to somewhat 
 strong solutions of salts of copper, produces a reddish-brown 
 
FERRI CYANIDE OF POTASSIUM TEST. 387 
 
 precipitate of chromate of copper, which is readily soluble in 
 ammonia, forming a beautiful green liquid ; the precipitate is 
 also soluble in acetic acid, and in excess of the copper solution. 
 From more dilute solutions, the reagent throws down a yellow 
 or greenish-yellow deposit. 
 
 !• To^ grain of oxide of copper, in one grain of water, yields 
 a very copious, reddish-brown, amorphous precipitate. 
 
 2. 1,0^00 grain : a copious, yellow deposit, which soon assumes 
 
 a greenish-yellow color. 
 
 3. 10,000 grain, yields an immediate, bluish-yellow turbidity, 
 
 and soon a quite satisfactory, greenish-yellow precipitate. 
 
 4- 4 0,000 grain : after several minutes, a quite perceptible tur- 
 bidity. 
 JBichromate of potash fails to produce a precipitate, even in 
 
 concentrated solutions of salts of copper. 
 
 9. Ferricyanide of Potassium. 
 
 Normal solutions of salts of copper, yield with this reagent, 
 a brownish-yellow or greenish-yellow amorphous precipitate of 
 ferricyanide of copper, which is insoluble in acetic acid, but is 
 readily soluble in ammonia, forming a beautiful green fluid. 
 !• Too" grain of oxide of copper, yields a copious, brownish- 
 yellow precipitate. 
 2. 1,0*0 grain : a very good deposit. 
 3- a , J grain : a rather good, greenish-yeUow precipitate. 
 
 4. 10,000 grain, yields a greenish turbidity. 
 
 The production of a brownish or greenish-yellow precipitate 
 by this reagent, is common to solutions of several other metals, 
 besides copper. 
 
 10. Iodide of Potassium. 
 
 This reagent produces in solutions of salts of copper a yel- 
 low or brownish-yellow precipitate, which soon changes to a 
 brownish or yellowish-white deposit of subiodide of copper 
 (GuJ.) ; at the same time, iodine is set free, and dissolves in 
 any excess of the reagent present. The precipitate is insoluble 
 
388 COPPER. 
 
 in acetic acid, but is readily soluble to a deep blue solution, in 
 
 ammonia. 
 
 1- Tou- grain of oxide of copper, yields a copious, brownish- 
 yellow precipitate, which soon acquires a yellowish-white 
 color. 
 
 2. i.Jou grain : a quite good deposit. 
 
 3. j^oora grain : the liquid assumes a yellow color, then be- 
 
 comes turbid, and after a short time, throws down small 
 granules. 
 
 4. lo.ouo grain : after a little time, the mixture acquires a yel- 
 
 low color, then becomes turbid. 
 
 The production by this reagent of a brownish or yellowish 
 precipitate, which is readily soluble in ammonia to a deep blue 
 solution, is quite peculiar to solutions of copper. 
 
 Detection of the Acid. — The tests now considered, would, 
 of course, only serve for the detection of the metal of the cu- 
 preous compound, and would not indicate the acid with which 
 it was combined. The presence of sulphuric, hydrochloric, or 
 nitric acid, when combined with the metal, could be shown in 
 the manner already described, under the special consideration 
 of these acids. 
 
 The presence of acetic acid, as in the case of verdigris, 
 could be shown by boiling the cupreous salt with a small quan- 
 tity of a mixture of about equal volumes of strong sulphuric 
 acid and alcohol, when acetic-ether of its characteristic odor 
 would be evolved. 
 
 Separation peom Organic Mixtures. 
 
 Suspected Solutions. — The soluble salts of copper are more 
 or less decomposed, with the precipitation of oxide of the metal 
 in combination with organic matter, by various animal and vege- 
 table principles. A portion of the clear liquid, after concentra- 
 tion if deemed best, may be slightly acidulated with sulphuric 
 acid, and a portion of a bright sewing needle placed in the 
 mixture, the immersion being continued for several hours if 
 necessary. Any metallic deposit thus obtained, may be washed 
 and confirmed, by dissolving the needle in diluted sulphuric 
 
SEPARATION FROM ORGANIC MIXTURES. 389 
 
 acid, and afterwards the washed coating in nitric acid, in the 
 manner already described, when considering the iron test. 
 
 In the application of this test, it should be borne in mind 
 that the needle may after a time, even in the absence of cop- 
 per, present a reddish appearance, due to the formation of a 
 coating of oxide of iron. A deposit of this kind, however, may 
 be readily distinguished from that produced by copper, even in 
 most instances by examining it with a hand-lens. Should the 
 iron test reveal the presence of copper, other portions of the 
 liquid may be examined by some of the other tests for the 
 metal. Most of these tests, however, have their action readily 
 interfered with by the presence of organic matter. 
 
 Should the liquid presented for examination be mixed with 
 much solid organic matter, the mixture, after the addition of 
 water if necessary, may be gently heated for some time, and a 
 portion of the filtered liquid then examined in the manner be- 
 fore described. Should there be a failure to thus detect the 
 poison, there would be little doubt of its entire absence. Yet, 
 the solids separated from the liquid by filtration, may be boUed 
 for about fifteen minutes with water containing a little hydro- 
 chloric acid, and the solution thus obtained be examined either 
 by the iron test or by sulphuretted hydrogen gas. 
 
 Contents of the Stomach. — These are carefully transferred to 
 a clean, porcelain dish, and the inside of the stomach well 
 scraped, the scrapings being added to the matters in the dish. 
 The contents of the dish, after the addition of water if neces- 
 sary, are strongly acidulated with hydrochloric acid, and gently 
 boiled until the organic solids are well broken up. The cooled 
 liquid is then filtered, the filtrate somewhat concentrated, again 
 filtered, and then exposed to a slow stream of sulphuretted 
 hydrogen gas, as long as a precipitate is produced, by which 
 any copper present will be thrown down as sulphuret of the 
 metal. When the precipitate has completely subsided, it is col- 
 lected on a filter, washed, and then dissolved, by the aid of 
 heat, in a small quantity of diluted nitric acid. On now treat- 
 ing the solution with a drop or two of sulphuric acid and cau- 
 tiously evaporating it to dryness, the metal, if present, will be 
 left as blue sulphate of copper. The residue thus obtained, is 
 
390 COPPER. 
 
 dissolved in a small quantity of warm water, and the filtered 
 solution examined for copper by the ordinary reagents, espe- 
 cially by the iron and ammonia tests. 
 
 Should the precipitate produced by siilphuretted hydrogen 
 be small in quantity and apparently contain miich organic mat- 
 ter, the residue obtained after solution in nitric acid and evap- 
 oration, is moistened with concentrated nitric acid and heated 
 until the organic matter is entirely destroyed. The dry mass 
 is then treated with a little diluted nitric acid, the liquid ex- 
 pelled by a moderate heat, the residue dissolved in a little pure 
 water, and the solution tested. 
 
 From the Tissues. — For the purpose of examining any of 
 the soft tissues of the body, for absorbed copper, the organ, as 
 a portion of the liver, cut into small pieces, is made into a 
 paste with pure nitric acid diluted with three or four volumes 
 of water, and the mixture gently boiled, with the occasional 
 addition of small quantities of powdered chlorate of potash, 
 until the whole becomes perfectly homogeneous. It is then 
 diluted with water, allowed to cool, and the filtered liquid evap- 
 orated to dryness. The residue thus obtained, placed in a thin 
 porcelain capsule, is covered with concentrated nitric acid, a 
 little chlorate of potash added, and the liquid evaporated by a 
 moderate heat ; the heat is then increased and continued until 
 the organic matter is entirely destroyed, when the mass will as- 
 sume a nearly white color. On boiling this residue in nitric 
 acid containing a little water, any copper present, together with 
 the small quantity of iron which is usually present in the tis- 
 sues, will be taken up in a soluble form. Thil* solution is care- 
 fully evaporated to dryness, to expel the excess of nitric acid, 
 the residue dissolved in a little warm water, and tested in the 
 usual manner. Should the solution contain iron, any copper 
 present may be separated from that metal by acidulating the 
 liquid with hydrochloric acid and treating it with sulphuretted 
 hydrogen, when the copper will be thrown down as sulphuret 
 of the metal, while the iron wiU remain in a soluble form ; the 
 precipitated sulphuret of copper is then collected on a filter, 
 washed, dissolved in a little nitric acid, and the solution exam- 
 ined in the manner already indicated. 
 
QUANTITATIVE ANALYSIS. 391 
 
 Another method for the separation of iron, when present in 
 a liquid with copper, is to treat the solution with excess of am- 
 monia, when the former metal will be precipitated as hydrated 
 sesquioxide of iron, while the copper will remain in solution, 
 forming a deep blue liquid. After removing the iron precipi- 
 tate by a filter, a portion of the filtrate may be slightly acidu- 
 lated with acetic acid, and tested with a solution of ferrocyanide 
 of potassium. 
 
 In a recent case of poisoning by the sulphate of copper, M. 
 Malagutti readily detected the metal in a portion of the liver 
 of the deceased ; and also, in about two ounces of the urine. 
 (Jour, de Chim. M^d., Avril, 1862, p. 209.) In experiments 
 on animals, in regard to the elimination of the salts of copper, 
 I. L. Orfila administered small quantities of the sulphate, mixed 
 with food, to dogs, for fifteen days, and found the metal in the 
 liver, tissue of the stomach, and in the lungs, sixty days after 
 it had been administered. Biit the metal was found in the urine 
 for only a few days after it had ceased to be taken ; and even 
 in some instances, it was not detected after the lapse of twenty- 
 four hours. (Orfila's Toxicologic, i, p. 791.) 
 
 From the Urine. — About five ounces of the urine are evap- 
 orated to dryness, and the organic matter of the residue de- 
 stroyed by means of concentrated nitric acid and chlorate of 
 potash, and subsequent incineration. The ash thus obtained, 
 which will generally contain a small trace of iron, is dissolved 
 in hot diluted nitric acid, and the liquid evaporated. Any 
 nitrate of copper present in the residue, is then dissolved in a 
 small quantity of water, and the solution examined in the usual 
 manner. 
 
 In six cases of non-fatal poisoning by salts of copper, col- 
 lected by M. Kletzinsky, the metal was found in the urine as 
 long as the patients experienced any active symptoms. When 
 these ceased, the metal disappeared from the urine ; but it con- 
 tinued to be discharged with the fseces. (Thudichum, Pathology 
 of the Urine, p. 409.) 
 
 Quantitative Analysis. — Copper is usually estimated as 
 protoxide of the metal. The solution is heated to about the 
 
392 ZINC. 
 
 boiling temperature, and a solution of caustic potash or soda 
 added as long as a precipitate is produced, after wliicli the 
 heat is continued for some minutes. When the mixture has 
 cooled and the supernatant liquid become perfectly clear, the 
 precipitate is collected on a filter of known ash, washed with 
 warm water, and dried. It is then, as far as practicable, sep- 
 arated from the filter, strongly ignited in an equipoised platinum 
 capsule, and the ash of the filter, Avhich has been burned sep- 
 arately, added to the ignited mass ; the whole is then allowed 
 to cool, and quickly weighed. When the quantity of precipi- 
 tate is small, it may be ignited along with the filter. 
 
 Should the alkaline liquid separated by filtration from the 
 precipitated oxide of copper, have a blue color, it is boiled 
 with a little grape-sugar, when any copper still present will be 
 thrown down as suboxide of the metal ; this is collected, washed, 
 moistened with nitric acid, the liquid evaporated, and the resi- 
 due ignited, when the copper will remain as protoxide of the 
 metal. One hundred parts by weight of anhydrous protoxide 
 of copper, represent 314-21 parts of pure crystallised sulphate 
 of copper ; or, in other words, the crystallised sulphate contains 
 3r825 per cent, of the anhydrous oxide. 
 
 Section III. — Zinc. 
 
 History and Chemical Nature. — The symbol for zinc is Zn, 
 its combining equivalent 32'53, and its specific gravity about 7. 
 Zinc is found in nature under several forms of combination, but 
 only in the inorganic kingdom. It is a bluish-white metal hav- 
 ing a bright metallic luster ; very brittle, and when fractured, 
 exhibits a crystalline structure. It fuses, according to Daniell, 
 at 773° F., and at a red heat is volatilised, being dissipated in 
 the form of a colorless vapor, which in the presence of air, 
 takes fire and burns with a white flame, forming oxide of zinc 
 (ZnO). When heated on a charcoal support before the reduc- 
 ing blow-pipe flame, it fuses, then burns, evolving dense white 
 fumes, and coating the charcoal with a yellow incrustation, 
 which on cooling becomes white. 
 
SULPHATE OF ZINC. 393 
 
 Exposed to the air, at ordinary temperatures, zinc becomes 
 covered with a grey coating of basic carbonate of zinc. The 
 metal is readily dissolved by nitric acid, with the formation of 
 nitrate of oxide of zinc, and evolution of either protoxide or 
 binoxide of nitrogen, the nature of the evolved gas depending 
 upon the strength of the acid employed. It is also readily sol- 
 uble in diluted sulphuric and hydrochloric acids, with the for- 
 mation of a salt of zinc, and the evolution of hydrogen gas. 
 As found in commerce, metallic zinc is liable to be contami- 
 nated with carbon, arsenic, sulphur, antimony, iron, lead, and 
 cadmium. 
 
 The only salifiable oxide of zinc, is the protoxide. This 
 forms a white, amorphous powder, which at elevated tempera- 
 tures, has a lemon-yellow color. The salts of zinc, unless they 
 contain a colored acid, are colorless. They are for the most 
 part readily soluble in water, and their normal solutions have a 
 slightly acid reaction. When intimately mixed with carbonate 
 of soda, and heated before the blow-pipe on a charcoal support, 
 the salts of zinc are readily decomposed, with the formation of 
 an incrustation, over the charcoal, of oxide of zinc. 
 
 When taken into the stomach, metallic zinc is destitute of 
 poisonous properties, at least so long as it retains its metallic 
 state ; but all the preparations of this metal are more or less 
 poisonous ; they are, however, less active than the compounds 
 of lead and copper. The continued inhalation of the oxide of 
 zinc, has, in several instances, given rise to serious symptoms. 
 (London Chem. Gaz., vol. viii, p. 362.) The only salts of zinc 
 requiring notice in this connection, are the sulphate and chlo- 
 ride. Poisoning by these salts has been of rare occurrence, and 
 has been chiefly the result of accident. 
 
 Sulphate of zinc, or tvhite vitriol (ZnO, SO3, HO, 6 Aq), as 
 usually found in the shops, is in the form of small, colorless, 
 prismatic crystals, which have a strong, astringent, metallic 
 taste, and are slightly eiHorescent in dry air. At 212° F., the 
 crystallised salt gives up six equivalents of water, and at about 
 400° becomes anhydrous ; at a bright red heat, it is entirely 
 decomposed, leaving a residue of oxide of zinc. It is soluble 
 in about two and a half times its weight of water, at ordinary 
 
394 ZINC. 
 
 temperatures ; and in less than its own weight of boiling water. 
 It is insoluble in alcohol, ether, and chloroform. 
 
 Chloride of zinc (ZnCl), is readily obtained by dissolving 
 zipc in diluted hydrochloric acid, and evaporating the solution 
 to diyness. In its anhydrous state, it forms a soft, white, very 
 deliquescent solid, which is readily fusible, and volatilises un- 
 changed at a strong red heat, condensing sometimes in the form 
 of colorless, crystalline needles. It is soluble in water in all 
 proportions, and also soluble in alcohol and ether. The liquid 
 known in the shops under the name of '^ Sir Wm. Burnett's 
 disinfecting fluid," is a solution of this salt, containing about 
 two hundred grains of the anhydrous salt in each fluid ounce. 
 Several instances of poisoning by this liquid have been reported. 
 
 Symptoms. — Sulphate of zinc has frequently been adminis- 
 tered in doses of several grains daily for long periods, without 
 producing any ill effects. Dr. Babington even gave, in one 
 instance, thirty-six grains of the salt, three times a day for 
 three weeks, without any ' noxious symptom having appeared. 
 When, however, the salt is swallowed in doses of several 
 drachms or more, it may produce very speedy and violent 
 symptoms, and even death. The usual symptoms are, an as- 
 tringent taste in the mouth, a sense of constriction and burning 
 in the throat and fauces, nausea, violent vomiting, intense pain 
 in the stomach and bowels, frequent purging, small and frequent 
 pulse, great anxiety, and coldness of the extremities. The 
 intellect usually remains clear. 
 
 A robust woman, aged twenty-five years, swallowed, by 
 mistake for Epsom salt, a solution containing an ounce and a 
 half of sulphate of zinc. She instantly vomited, and then be- 
 came affected with almost incessant retching and purging for 
 half an hour, which continued afterwards, at short intervals, for 
 three hours. There was also a small and frequent pulse, ex- 
 treme prostration, great ' anxiety, coldness of the body, violent 
 pain in the abdomen and limbs, with a sense of burning in the 
 throat and stomach, and death ensued in thirteen hours and a 
 half after the poison had been taken. A sister of this woman, 
 aged thirty-five years, took at the same time a similar dose of 
 the poison, but after several days of severe illness she finally 
 
PHYSIOLOGICAL EFFECTS. 395 
 
 recovered. In this instance, the vomiting was delayed for fif- 
 teen minutes, and there was no purging for ten hours ; the other 
 symptoms much resembled those of her sister, except the burn- 
 ing sensation in the throat, which was absent. (Amer. Jour. 
 Med. Sci., July, 1849, p. 279 ; from Brit, and For. Med.-Chir. 
 Rev., April, 1849.) 
 
 A case of suspected slow poisoning by the sulphates of zinc 
 and iron, has been recently reported by Dr. Wm. Herapath 
 (London Chem. News, June 16, 1865, p. 288). The symptoms 
 were a sense of burning heat in the stomach, fauces, and gullet, 
 coppery taste in the mouth, great thirst and nausea after eating 
 and drinking, followed by vomiting after from half an hour to 
 an hour. After death, the stomach was found considerably 
 inflamed in the cardiac portion, and its inner surface was in a 
 blistered state ; the intestines were but slightly inflamed. Traces 
 of sulphates of zinc and iron were found in the vomited mat- 
 ters, and also in the contents of the lower intestines ; but in 
 the contents of the stomach and duodenum, only sulphate of 
 iron was found. 
 
 In poisoning by solutions of the chloride of zinc, the symp- 
 toms are much the same as those caused by the sulphate. There 
 is an immediate burning sensation in the throat, burning pain 
 in the stomach, nausea, violent vomiting, purging, cold perspi- 
 rations, great anxiety, and feeble pulse. In some instances, 
 the vomited matters are streaked with blood, owing to the local 
 action of the poison upon the throat and neighboring parts. 
 
 In a case of poisoning by Burnett's disinfecting fluid, re- 
 ported by Dr. Letheby, the patient, a child fifteen months old, 
 was seized with extreme prostration, and died in a comatose 
 condition, ten hours after taking the dose. In a case communi- 
 cated to Dr. Taylor, a woman, aged twenty-eight years, swal- 
 lowed an ounce of this fluid, and died from its efi"ects four 
 hours afterwards. This is, perhaps, the most rapidly fatal case 
 of poisoning by zinc yet recorded. A woman, forty years of 
 age, swallowed a quantity of Burnett's fluid, in mistake for a 
 glass of gin. It remained on the stomach only about ten min- 
 utes, when it was ejected by vomiting. A burning sensation 
 was experienced in the throat and chest for two or three days ; 
 
396 ZINC. 
 
 this was succeeded by an inability of the stomach to retain 
 food, and death ensued at the expiration of fourteen weeks, 
 apparently from simple prostration, due to want of nourishment. 
 (Amer. Jour. Med. Sci., Jan., 1860, p. 190.) In an instance re- 
 ported by Dr. Stratton, of Montreal, a man, aged fifty-four years, 
 drank about a wine-glassful of a dense solution of chloride of 
 zinc, containing, as prepared, four hundred grains of the salt, 
 and entirely recovered from its effects ; not, however, without 
 experiencing very severe symptoms for several days. 
 
 As metallic zinc is more or less acted upon by certain arti- 
 cles of food, especially such as contain free organic acids or 
 fatty matters, its use for culinary operations, is not altogether 
 free from danger. In an instance in which we were consulted, in 
 1860, a family, consisting of eight persons, suffered with symp- 
 toms of zinc poisoning, occasioned by the use of apple-butter 
 prepared with cider, which had been concentrated on a gal- 
 vanised iron pan. On chemical examination, the concentrated 
 cider was found to contain 1-14 grains of oxide of zinc, in each 
 fluid ounce. 
 
 Treatment. — This is much the same as in poisoning by 
 salts of lead and copper. No chemical antidote is known. The 
 efforts of the stomach should be assisted by the free adminis- 
 tration of mild demulcent drinks. The free exhibition of a 
 mixture of milk and hydrate of magnesia, and, also, of decoc- 
 tions of the vegetable astringents, have been recommended. In 
 poisoning by the chloride of zinc, a solution of bicarbonate of 
 soda, followed by large draughts of any bland liquid, has been 
 advised. Opium may be found iiseful to allay the subsequent 
 irritation. 
 
 PoST-MOKTEM APPEARANCES. — In the case, already cited, in 
 which an ounce and a half of the sulphate of zinc proved fatal 
 in thirteen hours and a half, the following appearances were 
 observed, forty hours after death : great lividity of the external 
 surface of the body ; congestion of the brain and its mem- 
 branes ; a congested state of the lungs ; flaccid condition of the 
 heart, the right cavities being filled with black, thick blood ; 
 the inner surface of the stomach was covered with a yellowish, 
 pultaceous matter, on the removal of which a uniform yellow, 
 
CHEMICAL PROPERTIES. 397 
 
 ochrous color was observed, except towards the great curvature, 
 where it became reddish ; there was also a gelatiniform ramol- 
 lissement of the mucous membrane of the stomach, exposing, 
 in some parts, the submucous cellular tissue. The small intes- 
 tines Vt'ere somewhat injected, and contained yellowish matters. 
 In another case, the stomach was very vascular, spots of ecchy- 
 mosis being observable, and near the pylorus, slight ulceration. 
 The brain and its membranes were much congested, and the 
 pleura contained a large quantity of sanguinolent fluid. (Amer. 
 Jour. Med. Sci., July, 1849, p. 280.) In a case, quoted by 
 Dr. A. Stiiy (Mat. Med., vol. ii, p. 336), which proved fatal on 
 the fifth day, after a wineglassful of a concentrated solution of 
 sulphate of zinc had been taken, the only morbid appearances 
 detected, were patches of inflammation of the mucous mem- 
 brane of the pyloric end of the stomach and of the duodenum. 
 In Dr. Letheby's case of poisoning by Snrnett's disinfecting 
 fluid, before cited, twenty-two hours after death, the mucous 
 membrane of the mouth, fauces, and oesophagus, was found of 
 a white color and opake. The stomach was hard and leathery, 
 and contained about an ounce and a half of liquid resembling 
 curds and whey, in which chloride of zinc was afterwards found. 
 The inner surface of the stomach had a highly acid reaction, 
 was corrugated, opake, and tinged of a dark leaden hue ; this 
 appearance ceased abruptly at the pylorus. The lungs and 
 kidneys were congested. In the case of poisoning by this fluid 
 in which death did not occur until the lapse of fourteen weeks, 
 the stomach was found so much contracted as to contain only 
 four ounces of fluid, and completely perforated in two places by 
 ulcers, one being near the cardiac and the other near the py- 
 loric orifice. There was no decided peritonitis, but the whole 
 of the serous membrane had a slightly greasy feel when touched, 
 as if there were some exudation on its surface. 
 
 Chemical Properties. 
 
 In the Solid State. — When a few crystals of the sulphate 
 of zinc, placed in a watch-glass, are treated with a drop or two 
 of a solution of protochromate of potash, they acquire a yellow 
 
398 ZINC. 
 
 color, and soon become converted into a mass of small yellow 
 granules. This reaction, although perhaps not entirely peculiar, 
 readily serves to distinguish the least visible crystal of the zinc- 
 salt from the sulphate of magnesia, or Epsom salt, for which it 
 has in several instances been fatally mistaken, and which, when 
 treated in a similar manner, slowly dissolves. 
 
 If a small portion of sulphate of zinc be heated on a char- 
 coal support in the inner blow-pipe flame, it quickly fuses in 
 its water of crystallisation, and leaves a residue which is slowly 
 consumed, covering the charcoal in part with a yellow incrus- 
 tation of oxide of zinc, which on cooling becomes white. If 
 the unconsumed residue, or the incrustation, be moistened with 
 a solution of nitrate of cobalt, and then heated in the outer 
 flame of the blow-pipe, the mass on cooling acquires a green 
 color. These reactions are peculiar to compounds of zinc, and 
 will serve for the identification of very minute quantities of the 
 metal. It is usually best, however, before applying the blow- 
 pipe heat, to mix the zinc compound with carbonate of soda. 
 
 Of Solutions of Zinc. — Pure aqueous solutions of sulphate 
 of zinc are colorless, have a styptic, metallic taste, and slightly 
 redden litmus-paper. When a drop of the solution is allowed 
 to evaporate spontaneously, the salt is left in the form of 
 slender, prismatic crystals. As found in the shops, sulphate 
 of zinc is usuaUy contaminated with iron, and sometimes con- 
 tains other impurities, which more or less modify its chemical 
 reactions. 
 
 In ascertaining the limit of the reactions of the different 
 reagents for zinc, pure aqueous solutions of the sulphate were 
 employed. The fractions indicate the fractional part of a grain 
 of oxide of zinc (ZnO), present in one grain of the solution. 
 The results, unless otherwise stated, refer to the behavior of one 
 grain of the solution. One part of the oxide represents 3"54 
 parts of pure crystallised sulphate of zinc. 
 
 1. Sulphuretted Hydrogen. 
 
 Sulphuretted hydrogen gas throws down from neutral and 
 alkaline solutions of salts of zinc a white, amorphous precipitate 
 
SULPHURETTED HYDROGEN TEST. 399 
 
 of hydrated sulphuret of zinc (ZnS, HO), which is insoluble 
 in the caustic alkalies, alkaline sulphurets, and in acetic acid, 
 but very readily soluble in the stronger mineral acids. In solu- 
 tions containing either free sulphuric, hydrochloric, or nitric 
 acid, the reagent fails to produce a precipitate. Even in strong 
 solutions of the normal salts of these acids, the reagent throws 
 down only a portion of the zinc ; but from solutions containing 
 only about one per cent, or less of these salts, the precipitation 
 is complete. The separation of the precipitate, especially from 
 very dilute solutions, is much facilitated by the application of a 
 gentle heat. 
 
 The following results refer to the behavior of ten grains of 
 a normal solution of sulphate of zinc. 
 
 1. 100th solution of oxide of zinc (= xV grain ZnO), yields an 
 
 immediate precipitate, and soon there is a copious, white 
 deposit. 
 
 2. 1,000th solution : a quite good precipitate. 
 
 3. 10,000th solution: in a very little time, the liquid becomes 
 
 turbid, and after standing a few hours, yields a very 
 satisfactory deposit. 
 
 4. 25,000th solution : after a little time, the mixture becomes 
 
 turbid, and after a few hours, there is a quite distinct 
 deposit. 
 
 5. 50,000th solution : after a little time, the liquid becomes 
 
 cloudy, and after about ten hours, a distinct, flaky deposit 
 
 has formed. 
 The production of a white precipitate by this reagent is 
 characteristic of zinc, as this is the only metal the sulphuret of 
 which has a white color. It should be remembered that the 
 color of the precipitate may be much modified by the presence 
 of even minute quantities of other metals. It must also be 
 borne in mind, that solutions of sesquioxide of iron, may yield 
 with sulphuretted hydrogen a white turbidity, due to the decom- 
 position of the reagent with the separation of sulphur. 
 
 Sulpliuret of ammonium produces the same precipitate of 
 sulphuret of zinc from neutral and alkaline solutions of salts of 
 the metal. In this case, the precipitation is complete, even 
 from concentrated normal solutions of any of the salts of the 
 
400 ZINC. 
 
 metal. This reagent, however, also produces in solutions of 
 alumina a white precipitate of hydrated sesquioxide of alumina, 
 with evolution of sulphuretted hydrogen gas. This precipitate 
 is easily distinguished from the sulphuret of zinc, in being 
 readily soluble in caustic potash. 
 
 2. Potash and Ammonia. 
 
 The fixed caustic alkalies and ammonia throw down from 
 normal solutions of salts of zinc, and also from acid solutions 
 when excess of the reagent is added, a white precipitate of 
 hydrated oxide of zinc (ZnO, HO), which is readily soluble in 
 free acids, and in excess of the precipitant. From these alka- 
 line solutions, the whole of the zinc is reprecipitated, as sul- 
 phuret, by sulphuretted hydrogen gas. 
 
 1. x^ grain of oxide of zinc, in one grain of water, yields a 
 
 copious, gelatinous precipitate. 
 
 2. 1,000 grain : a quite good, flocculent precipitate, which readily 
 
 disappears on the addition of slight excess of the reagent. 
 
 3. lu.ouo grain, yields with a very minute quantity of the re- 
 
 agent, a slight turbidity. 
 
 These reagents also produce white precipitates in solutions 
 of various other substances, beside zinc ; but from these pre- 
 cipitates, the washed and dried oxide of zinc is readily distin- 
 guished, by its behavior under the blow-pipe flame, as already 
 pointed out. 
 
 The allnline carbonates throw down from solutions of salts 
 of zinc, a white precipitate of basic carbonate of the metal, 
 which is insoluble in excess of the fixed alkaline carbonates, 
 but soluble in excess of the carbonate and other salts of am- 
 monia. The precipitate is also readily soluble in acids, even 
 acetic acid, and in the caustic alkalies. The limit of the reac- 
 tion of these reagents, is the same as that of the free alkalies. 
 
 3. Ferrocyanide of Fotassium. 
 
 This reagent produces in solutions of salts of zinc a white, 
 amorphous precipitate of ferrocyanide of zinc (Zn^ Cfy, 3 HO), 
 
FERRICYANIDE OF POTASSIUM TEST. 401 
 
 which is insoluble in acetic, nitric, sulphuric, and hydrochloric 
 acids I also in ammonia, chloride of ammonium, and in excess 
 of the precipitant. In the presence of excess of the precipitant, 
 the precipitate acquires a greenish or greenish-blue color when 
 acted upon by hydrochloric or nitric acid, due to the decom- 
 position of the reagent. Ferrocyanide of zinc is readily soluble 
 in caustic potash, to a colorless solution, from which it is repre- 
 cipitated by an excess of hydrochloric acid. 
 
 1. 3-5- 0" grain of oxide of zinc, in one grain of water, yields a 
 
 very copious, gelatinous precipitate. 
 
 2. 1,000 grain : a quite good, flocculent deposit. 
 
 3. 10,000 grain : in a very little time, the mixture becomes 
 
 quite turbid. 
 
 4. 2 5 ,0 o "o grain : after a few minutes, a very perceptible tur- 
 
 bidity. 
 This reagent also produces white precipitates in solutions of 
 several other metals. Most of these precipitates, however, un- 
 like that from zinc, are readily soluble in hydrochloric acid. 
 
 4. Ferricyanide of Potassium. 
 
 Ferricyanide of potassium occasions in solutions of salts of 
 zinc a yellow, reddish-brown, or greenish, amorphous precipi- 
 tate, the color depending upon the strength of the solution, 
 and also, somewhat, upon the relative quantity of the reagent 
 present. The precipitate is insoluble in acetic, hydrochloric, 
 sulphuric, and nitric acids ; but readily soluble to a clear solu- 
 tion in potash, from which it is reprecipitated by hydrochloric 
 and sulphuric acids. It is also soluble in ammonia, but in a 
 very little time, the solution becomes turbid; from this solution, 
 it is also reprecipitated by acids. 
 
 1. YWo grain of oxide of zinc, yields a copious, dirty-yellow 
 
 precipitate, which very soon assumes a brownish color. 
 
 2. iJoo grain : a good, greenish-yeUow deposit. 
 
 3. 10,000 grain : a very fair, greenish turbidity, and very soon 
 
 a flocculent precipitate. 
 
 4. y a/o grain : the mixture very soon becomes turbid, and in 
 
 a little time, yields perceptible flakes. 
 
 26 
 
402 ZINC. 
 
 The reaction of this reagent is common to solutions of sev- 
 eral different metals. 
 
 5. Oxalic Acid. 
 
 Oxalic acid throws down from solutions of salts of zinc a 
 white, granular or crystalline precipitate of oxalate of zinc 
 (ZnO, C2O3, 2 Aq), which is insoluble in acetic acid, but readily 
 soluble in the stronger mineral acids ; it is also soluble in caus- 
 tic ammonia, but almost insoluble in chloride of ammonium. 
 The separation of the precipitate is much facilitated by a gentle 
 heat ; also by agitation of the mixture. 
 
 1. YWo grain of oxide of zinc, in one grain of water, yields an 
 
 immediate turbidity, and in a little time, a copious, gran- 
 ular precipitate. 
 
 2. iToiro grain : in a little time, a distinct precipitate, and soon, 
 
 a quite good deposit of granules and octahedral crystals, 
 Plate V, fig. 6. 
 
 3. 5,Joo grain : after several minutes, small granules form 
 
 along the margin of the drop, and in ten or fifteen min- 
 utes, there is a very satisfactory, granular and octahedral 
 deposit. 
 Oxalic acid throws down white precipitates from solutions 
 of salts of most of the metals, and in the case of lime, and also 
 of strontia, the precipitate may have the same microscopic char- 
 acters as the oxalate of zinc. The true nature of the zinc pre- 
 cipitate, however, may be readily determined by its behavior 
 before the blow-pipe. 
 
 6. Chromate of Potash. 
 
 Protochromate of potash produces in solutions of sulphate of 
 zinc a bright yellow, amorphous precipitate, which, according 
 to Thomson, consists of the subchromate of zinc. At ordinary 
 temperatures, the precipitate is somewhat slow to form, even 
 from strong solutions, but it separates immediately on the ap- 
 plication of heat. It is insoluble in excess of the precipitant, 
 but readily soluble in acetic acid, and in ammonia. 
 
PHOSPHATE OF SODA TEST. 403 
 
 1- ToT7 grain of oxide of zinc, yields, in tlie cold, an immediate 
 
 cloudiness, and soon a copious, yellow precipitate. 
 2. i.o'ou grain : an immediate turbidity, and soon a good, floc- 
 
 culent deposit. 
 3- ro75"o"o grain : after a little time, the mixture becomes quite 
 turbid. 
 This reagent produces similar yellow precipitates in solu- 
 tions of several other metals. 
 
 Bichromate of potash fails to produce a precipitate, even in 
 concentrated normal solutions of salts of zinc. 
 
 7. Phosphate of Soda. 
 
 Common phosphate of soda throws down from solutions of 
 salts of zinc a white precipitate of tribasic phosphate of zinc 
 (3 ZnO ; PO5), which is soluble in acids, even in acetic acid, 
 also in potash and ammonia, but only sparingly soluble in 
 chloride of ammonium. From strong solutions, the precipitate 
 as first produced is gelatinous, whilst from dilute solutions it 
 is flocculent; but after standing some time, it diminishes in 
 volume and becomes converted, at least partially, into crystal- 
 line plates : this change is produced immediately or in a very 
 Kttle time, by boiling the mixture. 
 
 !• Too" grain of oxide of zinc, yields a quite copious, gelatinous 
 precipitate. 
 
 2. 1,6*00 grain: a good, flocculent deposit. 
 
 3. 10,000 grain: after some minutes, a quite distinct turbidity. 
 The production of a white precipitate, by this reagent, is 
 
 common to solutions of quite a number of the metals. 
 
 Detection of the Acid. — The tests now considered, would, 
 of course, only serve for the detection of the base of the zinc- 
 salt. The presence of sulphuric acid, when combined with the 
 metal, may be readily detected by acidulating the solution with 
 nitric acid and treating it with chloride of barium, by which 
 the sulphuric acid will be precipitated as white sulphate of 
 baryta, which is insoluble in nitric acid. The presence of 
 hydrochloric acid may be determined by treating the solution, 
 
404 ZINC. 
 
 acidulated with nitric acid, with nitrate of silver, when any- 
 chlorine present will be thrown down as chloride of silver, 
 which is readily soluble in ammonia, but insoluble in diluted 
 nitric acid. 
 
 Sepaeation from Organic Mixtures. 
 
 Contents of the Stomach. — The same method of analysis is 
 equally applicable for the examination of suspected articles of 
 food, vomited matters, and the contents of the stomach. Salts 
 of zinc are more or less decomposed and precipitated by albu- 
 men, fibi'in, casein, and certain other organic principles. When, 
 therefore, the suspected mixture contains any solid matter, the 
 whole, after the addition of water if thought best, should be 
 acidulated with acetic acid and gently heated for some time, 
 when any organic precipitate of zinc present will be dissolved. 
 The solution thus obtained, is filtered, and the filtrate, after 
 concentration if necessary, treated with sulphuret of ammonium 
 as long as a precipitate is produced, after which it is gently 
 warmed, to facilitate the complete separation of the precipitate. 
 The precipitate is then collected on a filter, washed, and while 
 still moist, digested with nitric acid, in which the zinc will 
 dissolve, forming nitrate of the metal; at the same time, any 
 iron present will be oxidised and dissolved as nitrate of sesqui- 
 oxide of iron. The solution is now evaporated to dryness, to 
 expel the excess of acid, the residue dissolved in a small 
 quantity of distilled water, and the filtered liquid examined by 
 the ordinary tests for zinc. 
 
 Should the solution contain iron, which is a frequent impur- 
 ity in salts of zinc, the chemical reactions of the latter, as 
 already pointed out, will be more or less modified. These 
 metals may be separated by the addition of excess of caustic 
 ammonia, which will precipitate the iron as hydrated sesqui- 
 oxide, while the zinc wiU be redissolved and remain in solution. 
 Should the iron exist as protoxide of the metal, before precipi- 
 tating with ammonia, it must be converted into the sesquioxide, 
 by boiling the mixture with a little nitric acid. After separa- 
 ting the precipitated iron by a filter, the zinc in the ammoniacal 
 
QUANTITATIVE ANALYSIS. 405 
 
 filtrate may be precipitated by sulphuretted hydrogen gas; or, 
 the solution may be exactly neutralised with acetic acid, and 
 then tested in the ordinary manner. As this neutralisation 
 would give rise to a salt of ammonia, in which the precipitates 
 produced by many of the reagents for zinc are more or less 
 soluble, if only a minute quantity of the metal be present, it 
 is best to expel the excess of ammonia, by evaporating the 
 solution to dryness, and then redissolve the residue in a small 
 quantity of water containing a drop or two of acetic acid. 
 
 From the Tissues. — Absorbed zinc may be recovered by 
 boihng the finely divided tissue with nitric acid diluted with 
 five or six volumes of water, until the organic matter is com- 
 pletely disintegrated. The mass is then transferred to a muslin 
 strainer, the strained liquid evaporated to dryness, and the 
 residue moistened with pure nitric acid, and heated until the 
 organic matter is entirely destroyed. The dry mass thus ob- 
 tained, is treated with water containing a little hydrochloric 
 acid, the filtered liquid evaporated to dryness on a water-bath, 
 the residue dissolved in pure water, and the solution treated with 
 sulphuret of ammonium. Any precipitate thus obtained, is col- 
 lected, washed, and examined in the manner before described. 
 
 In several instances of poisoning by the salts of zinc, the 
 metal was readily discovered in the blood and tissues after 
 death, even in some cases after comparatively long periods. 
 It need hardly be remarked that, when the metal is found in 
 its absorbed state, it will be impossible from chemistry alone, 
 to determine in what form it was originally taken. 
 
 Quantitative Analysis. — Zinc is usually estimated in the 
 form of oxide of the metal. For this purpose, the solution is 
 heated to about the boiling temperature, and treated with a 
 somewhat dilute solution of carbonate of soda as long as a 
 precipitate is produced, after which it is boiled for some min- 
 utes. The precipitate is then allowed to subside, collected on 
 a filter, washed with hot water, dried, and ignited. The whole 
 of the zinc will now exist in the form of protoxide, one hund- 
 red parts of which correspond to 354'13 parts of pure crystal- 
 lised sulphate, or 167'77 parts of anhydrous chloride of zinc. 
 
PART SECOND. 
 
 VEGETABLE POISONS. 
 
VEGETABLE POISONS. 
 
 INTEODUOTION. 
 
 NATURE OF VEGETABLE POISONS GENERAL METHODS FOR RECOV- 
 ERING THE ALKALOIDS FROM ORGANIC MIXTURES. 
 
 The different poisonous plants owe their toxic properties to 
 the presence of one or more proximate principles, some of 
 which have not as yet been obtained in their isolated state. 
 Most of these active principles have basic properties, and such, 
 as a class, from their general chemical resemblance to the ordi- 
 nary alkalies, have been named ALKALOIDS, or vegetable al- 
 kalies. A few others, in regard to their chemical nature, are 
 neutral; while others still, have acid properties. In poisoning 
 by these substances, the poison is usually taken in its more or 
 less crude state ; but in some instances, as in the case of 
 strychnine, and morphine, it is not unfrequently taken in its 
 pure form. The present consideration of this class of poisons, 
 will be confined to such as contain principles, the nature of 
 which, even when present only in minute quantity, can be fully 
 established. 
 
 The natural alkaloids always exist in the plants from which 
 they are obtained, in the form of salts, which generally contain 
 an organic acid pecvdiar to the plant in which the base is found. 
 They all contain nitrogen, usually in the proportion of one 
 equivalent, but sometimes two equivalents, combined with vari- 
 ous proportions of carbon and hydrogen, sometimes alone, but 
 generally with the addition of oxygen. They are naturally 
 divided into two classes : the volatile, or liquid, and the fixed 
 alkaloids. 
 
410 VEGETABLE POISONS: INTRODUCTION. 
 
 The volatile alkaloids consist of carbon, hydrogen, and nitro- 
 gen ; are liquid at ordinary temperatures ; have a strong and 
 peculiar odor; and pass over with the vapor of water, when 
 their free aqueous solutions are distilled. On the other hand, 
 the fixed alkaloids contain carbon, hydrogen, nitrogen, and ox- 
 ygen ; are solid at ordinary temperatures ; destitute of odor ; 
 and do not distill with the vapor of water. In their free state, 
 most of the alkaloids are but sparingly soluble in water, but 
 readily soluble in alcohol, ether, and chloroform. Their salts 
 are, for the most part, soluble in water and in alcohol, but 
 insoluble in ether, and chloroform. 
 
 In their pure state, many of these substances may be identi- 
 fied with as much certainty, and in as minute quantity, as most 
 of the inorganic poisons ; but their detection when present in 
 complex mixtures, is generally much more difficult, requiring 
 more care and delicacy of manipulation, and is attended with 
 much greater loss of material, than the recovery of inorganic 
 substances. Again, as the quantity of the alkaloids necessary 
 to prove fatal, is usually very much less than that of inorganic 
 poisons, the actual quantity of poison present in death from the 
 former, is generally much less than that in poisoning by the 
 latter. Moreover, since all organic poisons sooner or later un- 
 dergo complete decomposition in the dead body, they can at 
 most be detected after only very limited periods, at least in 
 comparison with some of the metallic poisons. 
 
 From these considerations, it is obvious that in poisoning by 
 the vegetable alkalies, it may often happen that there will be a 
 failure to detect the poison. Even when the poison is discov- 
 ered, the amount recovered is frequently so minute as to ren- 
 der it impossible to make a quantitative analysis. In many 
 instances, the nearest approach that can be made as to the 
 quantity recovered, is by observing the intensity of the reac- 
 tions of the reagents applied, and comparing these with the 
 reactions of known quantities of the poison. 
 
 For the recovery and purification of the alkaloids, when 
 mixed with foreign matters, several general methods have been 
 proposed ; but, as might be expected, these processes are not 
 equally applicable for all the members of this class of poisons. 
 
RECOVERY BY METHOD OF STAS. 411 
 
 Some of these methods — most of which are based upon the 
 principles first pointed out, in 1851, by M. Stas, of Brussels — 
 will now be described, with some comments on each. 
 
 1. Method of Stas. 
 
 This method is much the same as that usually employed for 
 extracting the alkaloids from the vegetables in which they oc- 
 cur. It takes advantage of the fact that the acid salts of the 
 alkaloids are soluble in water and in alcohol ; and, that when a 
 solution of this kind is decomposed by the addition of an excess 
 of a fi"xed mineral alkali or its carbonate, and agitated with 
 pure ether, this liquid will dissolve the liberated alkaloid. In 
 the case of the volatile alkaloids, advantage is also taken of the 
 insolubility of their acid salts in ether, to separate such organic 
 impurities as are soluble in this liquid, by agitating the mixture 
 with the fluid while the alkaloid is in the form of a salt. 
 
 To apply this method, the suspected mixture, such as the 
 contents of the stomach, is treated with about twice its weight 
 of pure concentrated alcohol and from ten to thirty grains of 
 tartaric or oxalic acid, and the whole heated in a flask to about 
 160° F. If the substance under examination is one of the solid 
 organs of the body, as the liver, heart or lungs, it is first cut 
 into very small fragments and the mass moistened with strong- 
 alcohol, then strongly pressed, and the operation repeated with 
 fresh portions of alcohol, until the soluble matters are entirely 
 extracted ; the mixed alcoholic fluids are then acidified with 
 tartaric or oxalic acid, and heated in the manner just described. 
 
 When the alcoholic mixture has entirely cooled, the fluid is 
 filtered, the solids on the filter well washed with strong alcohol, 
 and the mixed filtrates evaporated to near dryness at a temper- 
 ature not exceeding 95° F., either in a strong current of air, 
 or in vacuo over sulphuric acid. If during the evaporation, 
 fatty or other insoluble matters separate, the concentrated fluid 
 is filtered, the filter washed with alcohol, and the filtrate and 
 washings evaporated as above, at a temperature not exceeding 
 95°. The residue is then digested with cold absolute alcohol, 
 the mixture filtered, the filter washed with alcohol, and the 
 
412 VEGETABLE POISONS: INTRODUCTION. 
 
 mixed liquids evaporated at a low temperature to dryness. 
 The residue thus obtained, is dissolved in a very small quan- 
 tity of water, and the solution treated with slight excess of pow- 
 dered bicarbonate of soda. The solution is now violently agi- 
 tated, in a stout test-tube or a small flask, with four or five 
 volumes of pure ether, the mixture allowed to repose, and then 
 a small portion of the clear supernatant ether transferred to a 
 watch-glass and allowed to evaporate spontaneously. 
 
 If the transferred ether contained a liquid alkaloid, in not too 
 minute quantity, it will now remain, in the watch-glass, as oily 
 streaks, which, upon the application of a very gentle heat, col- 
 lect into a drop and emit the peculiar pungent odor of the 
 alkaloid (nicotine or conine), more or less masked by that of 
 any animal matter present. If, however, a fixed alkaloid be 
 present, there will be traces of a solid residue, destitute of any 
 odor other than that of animal matter. 
 
 The alJcaloid is liquid and volatile. — If traces of a volatile 
 alkaloid are thus discovered, the contents of the vessel, from 
 which the small portion of ether was taken, are mixed with 
 from fifteen to thirty grains of a strong solution of caustic pot- 
 ash or soda, and the whole violently agitated ; after repose, the 
 clear ether is separated by means of a pipette, and the residue 
 washed in a similar manner three or four times with fresh por- 
 tions of ether. The mixed ethereal liquids are now agitated 
 with a small quantity of water containing sufficient diluted sul- 
 phuric acid to render the whole distinctly acid ; the ether is 
 then decanted, and the aqueous solution washed two or three 
 times with fresh portions of ether. 
 
 By this treatment, the aqueous solution will retain, in the 
 form of sulphate, any volatile alkaloid present ; while the de- 
 canted ether will remove such foreign matters as are soluble in 
 that liquid. As, however, the sulphate of conine is not alto- 
 gether insoluble in ether, this fluid may contain a small quan- 
 tity of that salt. 
 
 The aqueous solution is now mixed with an excess of a 
 concentrated solution of caustic potash or soda, and again 
 agitated with three or four volumes of pure ether, which will 
 dissolve the liberated alkaloid, and also any ammonia present. 
 
RECOVERY BY METHOD OF STAS. 413 
 
 The ether is then carefully decanted, the residue washed with 
 a fresh portion of ether, the mixed ethers exposed to spon- 
 taneous evaporation at a low temperature, and the last trace of 
 ammonia, if present, removed by placing the dish, containing 
 the residue, for a few moments in vacuo over strong sulphuric 
 acid, when the alkaloid will be left in its pure state. The 
 exact nature of the alkaloid is then determined by appropri- 
 ate tests. 
 
 The alkaloid is solid and fixed. — If the evaporation of the 
 small portion of ether, taken from the mixture neutralised by 
 bicarbonate of soda, does not indicate the presence of a volatile 
 alkaloid, the original mixture is treated with twenty or thirty 
 grains of a strong solution of potash or soda, and again violently 
 agitated; when the liquids have separated, the clear ether is 
 decanted, the residue thoroughly extracted with fresh portions 
 of ether, and the united ethereal liquids allowed to evaporate 
 spontaneously at a low temperature. The residue thus obtained, 
 is sometimes in the solid form, but more frequently as a color- 
 less milky liquid, in which are suspended small solid particles. 
 It has usually a distinct alkaline reaction, and an offensive 
 animal odor, which, however, is not pungent. 
 
 The residue is now treated with a few drops of alcohol, and 
 the liquid allowed to evaporate spontaneously. If this fails to 
 furnish the alkaloid in its crystalline form, a few drops of water 
 feebly acidulated with sulphuric acid, are added and gently 
 rotated over the residue. This will convert the alkaloid into a 
 sulphate of the base, which wiU dissolve ; while any fatty mat- 
 ters present, will usually remain undissolved and adhere to the 
 sides of the dish. The liquid is cautiously decanted or filtered, 
 the residue washed with a few drops of acidulated water, and 
 the mixed liquids evaporated to a small volume in vacuo, or 
 under a receiver over strong sulphuric acid. The concentrated 
 liquid is then rendered alkaline by a concentrated solution of 
 pure carbonate of potash or of soda, and the mixture treated 
 with absolute alcohol, which will dissolve the liberated alkaloid, 
 while the sulphate of potash formed, together with any excess 
 of carbonate of potash present, will remain undissolved. The 
 alcoholic solution is carefully decanted or filtered, and exposed 
 
414 VEGETABLE POISONS: INTRODUCTION. 
 
 to spontaneous evaporation, wlien the alkaloid will be left in its 
 pure state. Its true nature is now determined by the appro- 
 priate reagents. 
 
 On applying the principles now described, M. Stas states 
 that he has succeeded in isolating, when previously mixed with 
 foreign matters, the following alkaloids : nicotine, conine, aniline, 
 morphine, codeine, strychnine, brucine, veratrine, emetine, col- 
 chicine, aconitine, atropine, and hyoscyamine. He has also 
 thus extracted morphine from opium; strychnine and brucine 
 from nux vomica; veratrine from extract of veratrum; emetine 
 from extract of ipecacuanha; colchicine from tincture of colchi- 
 cum ; aconitine from an aqueous extract of aconite ; hyoscy- 
 amine from an old extract of henbane; and atropine from an 
 old tincture of belladonna. (Chemical Gazette, London, 1852, 
 p. 348, et seo[. ; from Bulletin de I'Academie de Medecine de 
 Belgique, vol. vi, No. 2.) 
 
 In applying the above method, the operator should bear in 
 mind that the different alkaloids differ greatly in regard to their 
 solubility in ether, and, therefore, that the quantity of this fluid 
 necessary for their complete extraction from aqueous or alkaline 
 mixtures will vary, other things being equal, with the nature 
 of the base. In all cases, the quantity of a given substance 
 that ether or any similar liquid will separate from its aque- 
 ous or alkaline solution — the quantities of the different liquids 
 being equal — will be in the same ratio as the solubility of 
 the substance in the former menstruum exceeds its solubility 
 in the latter. 
 
 For the extraction of most of the vegetable bases considered 
 in the present treatise, the method of Stas is very applicable; 
 but for others, it is only partially successful, or entirely fails, 
 especially when the alkaloid is present in very complex mix- 
 tures. Thus, solanine requires something over six thousand 
 times its weight of ether for solution, and therefore the quantity 
 of this liquid necessary for the extraction of even a small 
 quantity of the alkaloid is so great that it at the same time 
 dissolves so much foreign matter as to render the ethereal 
 residue unfit for the application of special tests. The same 
 
DETECTION BY METHOD OF STAS. 415 
 
 difficulty is also experienced in the separation of morphine, 
 which in its crystalline state requires nearly eight thousand 
 times its weight of ether for solution, and is at the same time 
 somewhat soluble in alkaline fluids. This difficulty is removed 
 to a considerable extent, as first suggested by Poellnitz, by 
 quickly agitating the aqueous or alkaline solution with ether 
 and decanting this fluid before the morphine assumes the crys- 
 taUine form. Again, in the case of nicotine, large quantities 
 and repeated agitations with ether are required for its complete 
 separation from aqueous solutions; since, although the alkaloid 
 is very soluble in ether, yet it is also freely soluble in water. 
 In the special consideration of the different alkaloids, their exact 
 solubility in water and ether, as well as in chloroform, will be 
 pointed out. 
 
 In the application of the above method for the detection of 
 the fixed alkaloids. Professor Otto strongly advises (Detection 
 of Poisons, p. 160) to pursue much the same course as that 
 advised for the recovery of the volatile, or liquid bases. Thus, 
 the organic mixture is treated with strong alcohol and oxalic or 
 tartaric acid, and the whole gently heated; the cooled liquid is 
 then filtered, the filtrate concentrated, the liquid again filtered, 
 then evaporated to near dryness, the residue extracted with 
 absolute alcohol, the filtered extract evaporated to dryness, and 
 the dry residue dissolved in a small quantity of water. All 
 these operations are conducted in the same manner as before 
 described. 
 
 Instead of now treating the aqueous solution — which con- 
 tains the alkaloid in the form of a salt — with bicarbonate of 
 soda or the caustic alkali, it is agitated with pure ether, and 
 the operation repeated as long as this liquid extracts any color- 
 ing matter; it is then treated with excess of a mineral alkali, 
 and again agitated with ether, which will now dissolve the 
 liberated alkaloid, and leave it, upon spontaneous evaporation, 
 in its nearly or altogether pure state, and not unfrequently in 
 the crystalline form. 
 
 Repeated experiments in our own hands, with several of the 
 fixed alkaloids, have fully confirmed the advantages claimed by 
 Professor Otto for this process. Even granting that the ether 
 
416 VEGETABLE POISONS: INTRODUCTION. 
 
 takes up a trace of the alkaloidal salt, still, he remarks, this 
 method deserves the preference, since a small quantity of the 
 alkaloid, in a pure state, is infinitely more valuable for our 
 purpose than a larger quantity in a state of impurity. 
 
 2. Method of Eodgees and G-irdwood. 
 
 This process was recommended by its authors (London Lan- 
 cet, June 28, 1856, p. 718) simply for the recovery of strych- 
 nine, but, with slight modifications, it is equally applicable for 
 the detection of most of the alkaloids. In principle it is much 
 the same as the method of Stas, only that chloroform instead of 
 ether is used as the solvent of the liberated alkaloid. The 
 details of this method are as follows: — 
 
 The organic mixture, as the contents of the stomach, is 
 treated with water acidulated with hydrochloric acid, and di- 
 gested at a modefate heat, for about two hours; when the mass 
 has cooled, the liquid is separated by means of a muslin strainer, 
 then filtered, and evaporated to dryness over a water-bath. 
 The residue thus obtained, is digested with strong alcohol con- 
 taining a few drops of hydrochloric acid, the solution filtered, 
 evaporated to dryness, and the residue extracted with distilled 
 water. This aqueous solution is filtered, the filtrate supersat- 
 urated with ammonia, and the mixture agitated with about half 
 an ounce of chloroform. When the chloroform has completely 
 subsided, it is transferred, by means of a pipette, to a small 
 evaporating dish, and evaporated to dryness. This residue 
 contains any strychnine present, together with more or less 
 foreign matter. To destroy the latter, the residue is moistened 
 with concentrated sulphuric acid and allowed to remain over a 
 water-bath for at least half an hour; then treated with pure 
 water, the mixture transferred to a test-tube, and when perfectly 
 cool, treated with slight excess of ammonia, and again agitated 
 with about half an ounce of chloroform. 
 
 The chloroform solution thus obtained, usually contains the 
 strychnine in a sufiiciently pure state for special testing. If, 
 however, a small portion of the liquid upon evaporation leaves 
 a residue, which when moistened with concentrated sulphuric 
 
RECpVERY BY METHOD OF USLAR AND ERDMANN. 417 
 
 acid becomes charred, the whole of the chloroform is evapo- 
 rated to dryness, and the residue charred with sulphuric acid, 
 in the manner just described, then dissolved in pure water, and 
 the solution, after the addition of ammonia, again agitated with 
 chloroform. 
 
 A small portion of the chloroform is now separated, by 
 means of a small pipette, and several drops or more allowed to 
 evaporate successively within as small a space as possible, in a 
 white porcelain capsule. The residue thus obtained, is then 
 tested in the ordinary manner. 
 
 In case the liver, spleen, or kidneys are the subject of anal- 
 ysis, the soUd organ should be reduced to a state of pulp in a 
 mortar, previous to digestion in acidulated water. In the case 
 of the tissues, if recent, they should be cut into very small 
 pieces, and triturated in a similar manner. 
 
 As most of the alkaloids are much more freely soluble in 
 chloroform than in ether, the former of these liquids is much 
 better adapted than the latter, for the separation of these poi- 
 sons from organic mixtures.- In no case, however, have we 
 found it necessary to resort to the use of concentrated sulphuric 
 acid, as advised by Messrs. Rodgers and Girdwood, for the de- 
 struction and separation of the foreign matter. 
 
 3. Method of Uslar and Eedmann. 
 
 This process is founded on the fact that the free alkaloids 
 are quite freely soluble in pure amylic alcohol ; while, on the 
 other hand, their chlorides are insoluble in this menstruum, and, 
 therefore, the former are readily removed from their solution in 
 this liquid, by shaking the mixture with water acidulated with 
 hydrochloric acid. The manipulations according to this method, 
 are the following : — 
 
 The suspected mixture, made if necessary into a thin paste 
 with water, is slightly acidulated' with hydrochloric acid, and 
 digested for one or two hours at a temperature of about 160° F. 
 It is then transferred to a linen cloth which has been previ- 
 ously moistened with water, and when the liquid has passed, the 
 
 27 
 
418 VEGETABLE POISONS: INTRODUCTION. 
 
 residue exhausted with hot water acidulated with hydrochloric 
 acid, and the combined liquids treated with slight excess of 
 ammonia, after which they are concentrated, first over an open 
 fire, then evaporated to dryness in a water-bath. The residue 
 thus obtained, is extracted three or four times with hot amylic 
 alcohol, and the united solutions filtered through paper, previ- 
 ously moistened with the alcohol. The filtrate has usually a 
 yellow color, and contains, besides the alkaloid, fatty and color- 
 ing matters. To free it from the latter, the liquid is transferred 
 to a cylindrical vessel, and violently agitated with several times 
 its volume of nearly boiling water, acidulated with hydrochloric 
 acid. By this operation the alkaloid is removed from its alco- 
 holic solution, being taken up by the acidulated water, while 
 the fat and coloring matter remain in the alcoholic liquid. 
 
 This fluid is now removed by means of a caoutchouc-pipette, 
 and the hot acid solution repeatedly extracted with fresh por- 
 tions of amylic alcohol, until the fatty and coloring matters are 
 completely removed ; after which the clear aqueous liquid is 
 concentrated somewhat by evaporation, then supersaturated 
 with ammonia, and the mixture well shaken with fresh, hot, 
 amyhc alcohol. 
 
 When the liquids have separated, the amylic alcohol, which 
 now contains the free alkaloid, is removed by means of a pi- 
 pette, and the acid solution again extracted with a fresh portion 
 of the hot alcohol. The mixed alcoholic liquids are then evap- 
 orated to dryness on a water-bath, when the alkaloid will be 
 left, often in a sufficiently pure state for special examination. 
 Should it, however, stiU present a yellowish or brownish color, 
 it is again dissolved in very dilute hydrochloric acid, the solu- 
 tion agitated with a fresh portion of the hot alcohol, the latter 
 liquid removed, and the aqueous solution treated with excess of 
 ammonia, then shaken with hot amylic alcohol, and this fluid 
 separated and evaporated as before. 
 
 The authors of this method cite a number of experiments in 
 which, by it, they succeeded in recovering small quantities of 
 morphine, narcotine, nicotine, conine, and strychnine, previ- 
 ously added to quite complex organic mixtures. In one of these 
 experiments, about the third of a grain of chloride of morphine 
 
RECOVERY BY METHOD OF GRAHAM AND HOFMANN. 419 
 
 was added to a calf's stomacli, and the latter exposed for a 
 fortnight to the action of the sun and air ; yet at the end of 
 that time, although the mass had become thoroughly putrid, the 
 alkaloid was recovered, and its presence indicated by the reac- 
 tion of perchloride of iron. (Liebig's Annalen, 1861, vol. 120.) 
 
 As morphine is quite soluble in amylic alcohol, while it is 
 almost insoluble both in ether and chloroform, the former of 
 these liquids is very much better adapted than either of the 
 latter for the separation of this base from organic mixtures. 
 But, for the separation of alkaloids about equally soluble in 
 these three liquids, we much prefer the use of ether or chloro- 
 form to that of amylic alcohol, as the latter separates more 
 slowly, than either of the others, from aqueous mixtures, and 
 also requires a longer time for its evaporation. Moreover, as 
 amylic alcohol requires a direct heat for its vaporization, any 
 alkaloid present, is much less likely to be left in its crystalline 
 state, than when it is deposited from ether or chloroform by 
 spontaneous evaporation. Most of the alkaloids are more freely 
 soluble in chloroform than in amylic alcohol. 
 
 4. Process of Geaham and Hofmann. 
 
 This method was first advised by Professors Graham and 
 Hofmann for the detection of strychnine, when present, in beer ; 
 but it has since been extended, by other experimenters, to the 
 separation of this and other alkaloids from other organic liquids. 
 It takes advantage of the fact that when a solution of strych- 
 nine is agitated with charcoal, the latter absorbs the poison, 
 and yields it up to alcohol when boiled with this liquid. The 
 following are the details of the process, as first employed by 
 its authors. 
 
 Two ounces of ivory -black, or animal charcoal, were shaken 
 in half a gallon of beer to which half a grain of strychnine had 
 been purposely added. After standing for about twelve hours, 
 the liquid was found to be nearly deprived of all bitterness ; 
 the strychnine being absorbed by the charcoal. The liquid 
 was now passed through a paper-filter, upon which the charcoal 
 
420 VEGETABLE POISONS; INTRODUCTION. 
 
 containing the strychnine was collected and drained. The char- 
 coal was then boiled for half an hour in eight ounces of ordinary- 
 spirits of wine, avoiding loss of alcohol by evaporation. 
 
 The alcoholic liquid, thus obtained, which now contained the 
 strychnine, was next filtered, and afterwards submitted to dis- 
 tillation. A residual watery fluid was thus obtained, holding 
 the strychnine in solution, but not sufficiently pure for the ap- 
 plication of tests. This solution was rendered alkaline by a few 
 drops of a solution of caustic potash, and then agitated with an 
 ounce of pure ether. The ethereal liquid, when separated and 
 allowed to evaporate spontaneously in a watch-glass, left the 
 alkaloid in a state sufficiently pure for testing. (Quart. Jour. 
 Chem. Soc, 1853, p. 173.) 
 
 Upon repeating this method, we find that from complex or- 
 ganic mixtures containing a very notable quantity of strychnine, 
 the alkaloid is extracted by the charcoal in a very nearly pure 
 condition, or at most requires only one agitation with ether or 
 chloroform to complete its purification; but when only a very 
 minute quantity of the poison is present, it either entirely 
 escapes detection or is so contaminated with foreign matter as 
 to require as many extractions with ether or chloroform, for its 
 purification, as to separate it by either of these liquids directly 
 from the prepared original mixture. In all cases, according to 
 our experience, this method is attended with greater loss of 
 material, than to prepare the mixture according to the process 
 of Stas, and then extract by chloroform. 
 
 5. Method by Dialysis. 
 
 Professor T. Graham has recently shown that moist organic 
 membranes possess the remarkable property of separating, when 
 in solution, crystaUisable substances from such as are uncrys- 
 taUisable, the former readily passing through such membranes 
 when surrounded by a liquid, whereas the latter entirely fail to 
 thus pass or do so only very slowly. (Jour. Chem. Soc, 1862, 
 p. 216.) The first of these classes, comprehending the crystal- 
 lisable substances, he named crystalloids, the second colloids ; 
 
RECOVERY BY DIALYSIS. 
 
 421 
 
 Fig. ]2. 
 
 and to this method of separation, he applied the term dialysis. 
 The most suitable substance for the dialytic septum, is the ma- 
 terial known as parchment-paper, which is prepared by immers- 
 ing unsized paper for a few moments in a cold mixture of two 
 measures of sulphuric acid and one of water. 
 
 For the application of this method, a light hoop of wood, 
 or better, of sheet gutta percha, about two inches in depth and 
 from five to ten inches in diameter, is covered with a piece of 
 moistened parchment-paper, so as to form a sieve-like vessel 
 (Fig. 12, a). The disc of paper used should exceed in diameter 
 the hoop to be covered by three or 
 four inches, so as to rise well up the 
 outside of the hoop, and it should be 
 bound to the hoop by a string or by 
 an elastic band, but it should not be 
 firmly secured. The parchment-paper 
 must be entirely free from rents or 
 pores. Its soundness may be ascer- 
 tained by sponging the upper surface 
 with pure water, and then observing 
 whether wet spots appear on the opposite side : in case they 
 do, the defects may be remedied by applying liquid albumen, 
 and then coagulating this by heat. The vessel thus prepared 
 is called the dialyser. 
 
 The liquid mixture to be examined is now poured into the 
 dialyser, upon the surface of the parchment-paper, but only in 
 such quantity as at most not to exceed about half an inch in 
 depth. The vessel, with its contents, is then floated in a basin 
 (6, Fig. 12) containing a quantity of pure water about four or 
 five times greater than the volume of liquid in the dialyser. 
 Any crystalloidal matter present, whether mineral or organic, 
 will now begin to pass through the parchment-paper into the 
 water in the larger vessel, and in twenty-four hours about two- 
 thirds or more of it may be found in the outer liquid, or diffu- 
 sate, as the latter is called. In most instances, the diffusion is 
 much promoted by the application of a gentle heat. 
 
 The difFusate is then concentrated, on a water-bath, to 
 .a small volume or evaporated to dryness, and the residue, if 
 
 (jTiaham s Appaiatus foi the Apjjli 
 cation of Dialysis 
 
422 VEGETABLE POISONS: INTRODUCTION. 
 
 sufficiently pure, examined by appropriate reagents. If, how- 
 ever, the residue is unfit for special testing, as will usually be 
 the case, at least in the case of the alkaloids, it is further puri- 
 fied by extraction with ether or chloroform, and then examined. 
 
 In a number of experiments by this method, for the separa- 
 tion of small quantities of different alkaloids from complex 
 organic liquids, we were much disappointed in the results, they 
 always falling far short of what we anticipated, especially in 
 regard to the purity of the diffused alkaloid. 
 
 Even when the diffusate contains a quite notable quantity 
 of the poison, the amount of colloidal, or amorphous matter also 
 present in the liquid, is not unfrequently such as to require for 
 its removal as many operations and as much labor, as to extract 
 the alkaloid at once from the original mixture by chloroform or 
 ether, according to the methods previously considered. More- 
 over, when only a minute quantity of the vegetable base is 
 present in the mixture submitted to examination, as a portion 
 of the poison always remains in the dialyser, it may entirely 
 escape detection, even when the quantity present in the original 
 mixture is sufficient to give satisfactory results by the chloro- 
 form or ether method. 
 
 These results closely accord with those obtained from simi- 
 lar experiments by Dr. Harvey. (London Lancet, Jan. 3, 1863, 
 p. 6.) Some quantitative experiments in regard to the merits 
 of this method for the extraction of small quantities of strych- 
 nine, will be detailed hereafter, in the special consideration of 
 that alkaloid. 
 
 From the fact, that in poisoning by metallic compounds the 
 quantity present is generally much greater than in poisoning by 
 vegetable substances, and, also, as the former usually diffuse 
 somewhat more readily than the latter, through membranes, 
 dialysis seems better adapted, in medico-legal examinations, for 
 the detection of mineral than of organic poisons. 
 
NICOTINE. 423 
 
 OHAPTEE I. 
 
 VOLATILE ALKALOIDS: NICOTINE, CONINE. 
 
 Section I. — Nicotine. (Tobacco.) 
 
 History. — Nicotine, nicotina, or nicotia, is the active princi- 
 ple of the common tobacco plant, Nicotiana Tahacum, in which 
 it occurs in combination with malic acid ; it exists in the leaves, 
 root, and seeds of the plant, and also in the smoke of tobacco. 
 Nicotine is destitute of oxygen, its formula being C20H14N2; or 
 according to some observers, C10H7N. Vauquelin, in 1809, was 
 the first to attempt the separation of this active principle, and 
 he succeeded in discovering some of the properties of some of 
 its compounds, but failed to isolate the pure alkaloid. Posselt 
 and Reimann, in 1828, were the first to separate the alkaloid ; 
 in 1842, Ortigosa analysed some of its compounds, and Barral 
 analysed nicotine itself. (Gmelin's Hand-book, vol. xiv, p. 220.) 
 
 Preparation. — Nicotine may be prepared, as first proposed 
 by M. Schloesing, in the following manner : Coarsely powdered 
 tobacco is boiled with water, the cooled liquid strained through 
 linen, then evaporated to the consistency of a syrup, and while 
 hot agitated with twice its volume of alcohol of sp. gr. 0-837. 
 After standing some time, the liquid portion of the mixture, 
 which contains the whole of the vegetable base, is decanted 
 from the black and almost solid deposit, then concentrated, and 
 mixed, while still warm, with a solution of potash, by which 
 the alkaloid will be set free. The cooled mixture is agitated 
 with ether, which will dissolve the liberated base, together with 
 some coloring matter. After repose, the ethereal liquid is de- 
 canted and agitated with powdered oxalic acid, when, after a 
 time, the oxalate of nicotine thus formed will subside as a 
 syrupy mass. This, after the decantation "of the ether, is 
 washed with fresh ether, then rendered alkaline with potash and 
 
424 NICOTINE. 
 
 again agitated wit^ ether, which will now dissolve the alkaloid. 
 The ethereal solution is transferred to a retort, the ether dis- 
 tilled off, and the residue exposed for some hours, at a temper- 
 ature of about 284° F., to a current of hydrogen gas, by which 
 the last traces of ether, water, and ammonia will be separated ; 
 the heat is then increased to about 356° F., when the alkaloid 
 will distill over pure and colorless. 
 
 The proportion of nicotine varies greatly in different kinds 
 of tobacco. According to Schloesing (Chem. Gaz., v, p. 43), 
 some dried French samples contain from 7 to 8 per cent, of the 
 alkaloid ; Virginia and Kentucky, 6 or 7 per cent. ; while Mary- 
 land and Havanna, only about 2 per cent., which is about the 
 proportion found in ordinary snuff. 
 
 Nicotine is a transparent, colorless, oily liquid, and one of 
 the most active poisons known, even equaling in the rapidity 
 of its action hydrocyanic acid. There are however, perhaps, 
 only two instances yet recorded of poisoning of the human sub- 
 ject by this substance in its pure form ; but poisoning by to- 
 bacco, which owes its activity entirely to this alkaloid, is not 
 of unfrequent occurrence. The following consideration in re- 
 gard to the physiological effects of the alkaloid, will, therefore, 
 be based chiefly upon its action as observed in cases of poison- 
 ing by tobacco. 
 
 Symptoms. — The usual effects produced by a poisonous dose 
 of tobacco, when taken into the stomach, are confusion in the 
 head, paleness of the countenance, vertigo, nausea, severe retch- 
 ing and vomiting, heat in the stomach, great anxiety, a sense 
 of sinking at the pit of the stomach, with extreme prostration, 
 trembling of the limbs, and sometimes violent purging. The 
 pulse is small, feeble, and almost imperceptible ; the respiration 
 difficult, and the skin cold and clammy ; the pupils are gener- 
 ally dilated, but sometimes contracted, and the vision is usually 
 more or less impaired. Death is often preceded by convulsions, 
 and paralysis. 
 
 In regard to the operation of tobacco. Dr. Pereira remarks, 
 that it resembles that of Lobelia inflata. With foxglove, to- 
 bacco agrees in several particulars, especially in that of enfee- 
 bling the action of the vascular system, though its power in this 
 
PHYSIOLOGICAL EFFECTS. 425 
 
 respect is inferior to that of foxglove. In its capability of 
 causing relaxation and depression of the muscular system, and 
 trembling, tobacco surpasses foxglove ; as it does, also, in its 
 power of promoting the secretions. From belladonna, stramo- 
 nium, and hyoscyamus, it is distinguished by causing contrac- 
 tion of the pupil, both when applied to the eye and when taken 
 internally in poisonous doses ; and also by the absence of de- 
 lirium and of any affection of the parts about the throat. (Mat. 
 Med., vol. ii, p. 494.) 
 
 Administered in the form of clyster, tobacco has in several 
 instances caused death. In a case of this kind quoted by Dr. 
 Christison, in which an enema prepared by boiling about an 
 ounce of tobacco for fifteen minutes in water was administered 
 by the advice of a quack to an individual laboring under ob- 
 stinate constipation, the patient was seized in two minutes 
 afterwards with vomiting, violent convulsions, and stertorous 
 breathing, and died in three-quarters of an hour. 
 
 So, also, the external application of tobacco to abraded sur- 
 faces, and even to the healthy skin, has been attended with 
 violent symptoms, and even death. In a case of this kind, in 
 which a man applied to himself a decoction of tobacco for the 
 cure of an eruptive disease, death took place in three hours, 
 with the usual symptoms of tobacco poisoning. (See Amer. 
 Jour. Med. Sci., Jan., 1865, p. 268.) 
 
 Even the smoking of tobacco has been known to produce 
 dangerous, and even fatal results. Dr. Marshall Hall relates 
 the case of a young man, who, having smoked two pipes of 
 tobacco, was seized with nausea, vomiting, syncope, stupor, 
 stertorous breathing, and general spasms : after a time he re- 
 covered. Gmelin mentions two cases of death, caused in one 
 instance by the smoking of seventeen, and in the other of 
 eighteen pipes of tobacco, at a sitting. 
 
 A most remarkable case -of poisoning by nicotine in its pure 
 state, occurred in Belgium, in 1850, for which the Count de 
 Bocarme was condemned ta death, the person murdered being 
 his brother-in-law, Gustavo Fougnies. An unknown quantity 
 of the poison was forcibly administered, and it is believed that 
 death took place within five minutes afterwards. Nicotine was 
 
426 NICOTINE. 
 
 detected in small quantity by M. Stas in the mouth, throat, 
 stomach, liver, and spleen of the deceased, and also in the floor 
 near which the act was committed. (Orfila's Toxicology, vol. 
 ii, p'. 498.) The only other related case of poisoning by this 
 substance in its pure state, occurred in London, in 1858, and 
 death took place in from three to iive minutes after the poison 
 had been taken. In this case, a small quantity of the poison 
 was detected by Dr. Taylor in the contents of the stomach. 
 
 In this connection, we may briefly relate the following ex- 
 periments, in regard to the action of nicotine in its pure state. 
 One drop of the poison placed in the mouth of a full-grown 
 cat, produced immediate prostration, continued convulsive move- 
 ments of the extremities, and death in seventy-eight seconds after 
 the poison had been administered. In another case, a small 
 drop was placed on the tongue of a cat. In ten seconds, the 
 animal fell on the right side perfectly prostrated, then had con- 
 vulsive movements of the legs, voided urine, and died in two 
 minutes and a half. A third cat, to which a similar quantity 
 had been administered, fell in about ticelve seconds, had violent 
 convulsions of the extremities, and was dead in seventy-five 
 seconds after taking the poison. 
 
 Period tvJien Fatal. — In fatal poisoning by tobacco, death 
 does not usually occur until after some hours, but it may take 
 place within a very much shorter period. In a case in which 
 about an ounce of crude tobacco had been swallowed, death 
 took place in about seven hours ; while in another, an unknown 
 quantity of snuff administered in whisky, proved fatal in about 
 one hour. 
 
 Most of the reported cases of death from tobacco have been 
 occasioned by its use in the form of clyster. M. Tavignot re- 
 lates a case in which an injection prepared by mistake with 
 nearly two ounces of tobacco (60 grammes), instead of nine 
 grains and a quarter (60 centigrammes), was administered to a 
 stout man, aged fifty-five years. In seven or eight minutes 
 afterwards, he was seized with stupor, headache, paleness of 
 the face, pain in the abdomen, indistinct articulation, and con- 
 vulsive tremors, at first of the arms, then of the whole body. 
 These symptoms were soon followed by extreme prostration and 
 
PATHOLOGICAL EFFECTS. 427 
 
 slow laborious breathing, and then coma, which terminated 
 fatally in about eighteen minutes after the injection had been 
 administered. (Grazette Med. de Paris, Nov., 1840, p. 763.) 
 In a case quoted by Dr. Beck (Med. Jur., vol. ii, p. 878), a 
 female affected with worms used an enema of tobacco, and was 
 soon seized with violent convulsions, and died from its effects 
 fifteen minutes afterwards. 
 
 Fatal Quantity. — In most of the fatal cases of poisoning 
 from the swallowing of tobacco, the quantity taken could not be 
 accurately determined. In a case reported by Mr. Skae, a man 
 who had swallowed a large mouthful of crude tobacco, became 
 suddenly insensible, motionless, and relaxed, with contracted 
 pupils, and a scarcely perceptible pulse. These symptoms were 
 followed by convulsions, loud cries, dilated pupils, active vom- 
 iting and purging, and death by syncope. (Stille's Mat. Med., 
 vol. ii, p. 298.) 
 
 Administered in the form of enema, tobacco has proved 
 fatal in comparatively small quantity. Thus, several instances 
 are reported in which a decoction of a drachm exhibited in this 
 manner caused death. In one of these, quoted by Dr. Christi- 
 son, death took place in thirty-five minutes. In a case cited 
 by Dr. Pereira (Mat. Med., ii, 494), an injection containing 
 only half a drachm was followed by fatal results. 
 
 Treatment. — This consists in the speedy removal of the 
 poison, in case it has been swallowed, from the stomach ; and 
 the subsequent exhibition of stimulants. Animal charcoal, tan- 
 nic acid, and an aqueous solution of iodine in iodide of potas- 
 sium have been advised as chemical antidotes. Opium may 
 sometimes be found useful, to allay the excessive vomiting. 
 
 PosT-MOETEM APPEARANCES. — These are subject to great 
 variation. In a case cited by Dr. Taylor (On Poisons, p. 747), 
 in which something less than an ounce of crude tobacco had 
 been swallowed and death occurred in about seven hours, the 
 following appearances were observed forty hours after death. 
 The substance of the brain and the upper part of the spinal 
 marrow were somewhat congested ; the heart was empty, small, 
 and contracted; and the liver and kidneys much congested. 
 The mucous membrane of the stomach presented several red 
 
428 NICOTINE. 
 
 patches. The intestines were contracted throughout and con- 
 tained only a mucus fluid tinged with blood; the mucous mem- 
 brane was of a red color, partially abraded, and full. The 
 bladder was contracted and empty. The blood throughout the 
 body was dark colored and liquid. 
 
 In a case in which an enema prepared with about an ounce 
 of tobacco proved fatal in three-quarters of an hour, the only 
 abnormal appearances observed two days after death, were a 
 gorged condition and redness of the inner and outer coats of the 
 large and small intestines, and patches of extravasation in some 
 parts of the mucous membrane, together with an empty state 
 of the heart and of the blood vessels of the abdomen. The 
 stomach and brain were natural. 
 
 Chemical Peopekties. 
 
 General Chemical Nature. — Nicotine, when perfectly 
 pure, is a transparent, colorless, oily liquid, having a strong 
 alkaline reaction, and a density of about 1'048. Its odor is 
 usually described as acrid, unpleasant, and resembling some- 
 what that of tobacco : this is true of most samples as met with 
 in the shops, but when perfectly pure, it has, as remarked by 
 Otto, a rather pleasant, ethereal odor. The odor may be per- 
 ceived, but is not characteristic, in a few drops of a pure 
 50,000th aqueous solution of the poison. 
 
 Nicotine has a pungent, acrid taste, even when highly dilu- 
 ted, producing a peculiar sensation in the throat and air pas- 
 sages. It slowly distills at about 295°, and boils at about 470° 
 F., recondensing for the most part unchanged ; in an atmos- 
 phere of hydrogen gas, it may be distilled without any decom- 
 position. It imparts a transient greasy stain to white paper, 
 and burns with a white, smoky flame. On exposure to the air, 
 nicotine slowly becomes yellow, then brownish and thick, being 
 finally converted into a resinous mass. 
 
 Soliibility. — Nicotine is freely soluble in all proportions in 
 water ; it is also soluble in alcohol, ether, chloroform, the fixed 
 oils, and in oil of turpentine. By the use of some of these 
 latter solvents, the alkaloid may be extracted to a greater or 
 
SPECIAL CHEMICAL PROPERTIES. 429 
 
 less extent, from its solution in water. For this purpose, ether 
 has usually been employed, but this liquid is inferior in this 
 respect to chloroform, as may be seen from the following facts. 
 
 1. Extraction hy Ether. — When one volume of a 100th aque- 
 ous solution of nicotine is agitated with five volumes of absolute 
 ether, and the latter liquid, after repose, decanted, the aqueous 
 solution yields with reagents somewhat better reactions of the 
 presence of nicotine than a pure 500th solution of the alkaloid; 
 thus showing that the ether extracted less than four-fifths of the 
 vegetable base. When a 100th solution is agitated with twenty- 
 five volumes of ether, the aqueous liquid is reduced to about a 
 1,200th solution. Experiments made with aqueous solutions of 
 the chloride of nicotine, by decomposing the salt with caustic 
 potash and then extracting with absolute ether, gave results 
 similar to those just mentioned; as did also experiments in 
 which concentrated commercial ether was employed as the ex- 
 tracting liquid. 
 
 2. By Chloroform. — When a 100th aqueous solution of pure 
 nicotine is agitated with five volumes of pure chloroform, and 
 the latter carefully decanted, the former liquid is reduced to 
 about a 4,000th solution of the alkaloid. So, also, under like 
 circumstances, a 1,000th aqueous solution is reduced to about 
 a 40,000th solution. These experiments show that under these 
 conditions, chloroform separates about. 39-40ths of the alkaloid. 
 
 Special Chemical Pkoperties. — If a drop of nicotine be 
 placed in a watch-glass, and this covered by a similar, inverted 
 glass containing a small drop of either hydrochloric or nitric 
 acid, the glasses become filled with white fumes. These fumes 
 are not so dense as those obtained from conine under similar 
 circumstances ; nor are they, as in the case of conine, attended 
 with the formation of crystals. When the pure alkaloid is 
 treated directly with concentrated hydrochloric acid, it yields a 
 syrupy liquid, without the formation of crystals; with nitric 
 acid, it yields a reddish syrupy fluid. When the alkaloid is 
 touched with concentrated sulphuric acid, it undergoes little or 
 no change, until the mixture is heated, when it acquires a 
 brownish color. It need hardly be added, that these reactions 
 in themselves are not characteristic of this alkaloid. 
 
430 NICOTINE. 
 
 A pure aqueous solution of nicotine is colorless, has the pe- 
 culiar odor and taste of the alkaloid, and an alkaline reaction. 
 When such a solution is distilled, the alkaloid passes over with 
 the vapor of water. Nicotine readily unites with acids, forming 
 salts, some of which are readily crystallisable. 
 
 The salts of nicotine have the peculiar taste of the alkaloid, 
 but are destitute of odor. They are mostly soluble in water, 
 and alcohol, but insoluble in ether. Their aqueous solutions 
 lose part of the alkaloid upon evaporation, and are decomposed 
 by the mineral alkalies, evolving the odor of nicotine. When 
 such an alkaline mixture is agitated with chloroform, this liquid, 
 after decantation and evaporation, leaves the extracted alkaloid 
 in the form of oily drops or streaks. On distilling a solution of 
 a salt of nicotine which has been treated with excess of caustic 
 potash or soda, the free alkaloid will be found in the distillate, 
 together with any ammonia that may have been present in the 
 mixture. If the distillate thus obtained, be neutralised with 
 oxalic acid, then gently evaporated to dryness, and the residue 
 treated with alcohol, this liquid will dissolve the oxalate of 
 nicotia, produced by the neutralisation, while any oxalate of 
 ammonia present will remain, it being insoluble in this men- 
 struum. On now evaporating the alcoholic solution to dryness, 
 the oxalate of nicotine may be obtained in its pure state. 
 
 In the following examinations of the limit of different tests 
 for nicotine when in solution, the pure, colorless alkaloid was 
 dissolved in distilled water. The fractions indicate the frac- 
 tional part of a grain of the alkaloid in solution in one grain 
 of water. The results, except when otherwise stated, refer to 
 the behavior of one grain of the solution. 
 
 1. Bichloride of Platinum. 
 
 This reagent throws down from somewhat strong aqueous 
 solutions of nicotine and of its salts, a yellow precipitate of the 
 double chloride of platinum and nicotine, having, according to 
 Ortigosa, the composition C20H14N2, 2HC1; 2 PtCl. The precip- 
 itate produced from free aqueous solutions of the alkaloid by 
 the pure reagent, is at first amorphous, but after a little time it 
 
BICHLORIDE OF PLATINUM TEST. 431 
 
 becomes, in part at least, crystalline. But when from solutions 
 of the chloride of nicotine, or if the reagent contains free hy- 
 drochloric acid, the precipitate immediately assumes the crys- 
 talline form. From more dilute solutions of the alkaloid or of 
 its salts, the precipitate separates only after a time, and then 
 in the crystalline state ; its separation is much facilitated by 
 stirring the mixture. The precipitate, in its crystalline form, 
 dissolves but slo'vi'ly in large excess of hydrochloric acid ; in its 
 amorphous condition, however, it is much more readily sol- 
 uble. It is insoluble in acetic acid, alcohol, and in ether, but 
 soluble in excess of free nicotine. The crystals are permanent 
 in the air. 
 
 1. -j-g-g- grain of nicotine, in one grain of water, yields with the 
 
 reagent a quite good deposit of orange-yeUow crystals, 
 Plate VI, fig. 1. 
 
 2. 5-^ grain : after a little time, the mixture becomes turbid, 
 
 and ultimately yields small crystals of the double salt. If 
 the mixture be stirred with a glass rod, it very soon yields 
 granular streaks on the dish or glass-slide over the path 
 of the rod ; and in a little time, a quite satisfactory crys- 
 talline deposit. 
 Bichloride of platinum also produces yellow crystalline pre- 
 cipitates in solutions of potash and ammonia; but the forms of 
 the crystals thus produced are wholly different from those of 
 the double nicotine salt. (Compare Plate I, fig. 1.) The ap- 
 plication of some of the tests, such as the iodine reagent, which 
 produce precipitates with nicotine but none with the inorganic 
 alkalies, would also readily distinguish the former from the 
 latter. If the solution under examination has been prepared by 
 extraction from a suspected mixture by chloroform or ether, 
 then a mineral alkali could not be present, since they are insol- 
 uble in each of these liquids. 
 
 This reagent also throws down yellow precipitates from solu- 
 tions of most of the other alkaloids, some of which, like the 
 nicotine deposit, are crystalline ; but in no instance have the 
 crystals the same microscopic forms as those obtained from 
 somewhat strong solutions of nicotine. The production of this 
 crystalline precipitate, together with the odor and physical state 
 
432 NICOTINE. 
 
 of nicotine, readily serve to distinguish this alkaloid from all other 
 substances. 
 
 2. Corrosive Sublimate. 
 
 This reagent produces in strong solutions of nicotine a copi- 
 ous, white, curdy precipitate, which soon acquires a yellow color 
 and deposits beautiful groups of colorless crystals, which are 
 permanent in the air. The precipitate produced from some- 
 what dilute solutions of the alkaloid, remains white, and after a 
 time yields the same crystals as from strong solutions. These 
 precipitates are readily soluble in hydrochloric and acetic acids. 
 The white precipitate is soluble in chloride of ammonium, from 
 which after a time it is redeposited ; the yellow precipitate is 
 immediately decolorised by chloride of ammonium, and, in part 
 at least, dissolved, but after a time it separates in the form of 
 a white powder. The precipitates are to a greater or less ex- 
 tent dissolved upon the application of heat, but again repro- 
 duced as the solution cools. 
 
 1. y^ grain of nicotine, in one grain of water, yields a copi- 
 
 ous, white precipitate, which in a little time becomes yel- 
 low and yields a mass of large groups of crystals, Plate 
 VI, fig. 2. These crystals are especially beautiful under 
 polarized light. 
 
 2. Too' grain, yields a rather copious, dirty-white precipitate, 
 
 which soon deposits colorless crystals. 
 
 3. t:o~o~o grain : in a few seconds, the mixture becomes turbid, 
 
 and soon there is a quite good, white, flocculent precipi- 
 tate, which after a time yields crystals having the same 
 forms as illustrated above. If upon the addition of the 
 reagent, the mixture be stirred with a glass rod, it imme- 
 diately yields streaks on the bottom of the watch-glass 
 over the path of the rod, and soon innumerable opake 
 granules and granular masses appear, which after a little 
 time present the appearances illustrated in the lower por- 
 tion of the above figure. 
 4:. iTsVo grain : if the mixture be stirred and allowed to stand, 
 it yields after some time, quite a number of large crystal- 
 line groups. 
 
CARBAZOTIC ACID TEST. 433 
 
 Although corrosive sublimate also produces white precipi- 
 tates with ammonia and various inorganic substances, as well 
 as with most of the alkaloids and many other kinds of organic 
 matter, yet all these deposits, vmlike that from nicotine, remain 
 amorphous, except the precipitate from strychnine, and in this 
 case, the crystals, which are usually obtained with difficulty, 
 are always of a wholly different form from those produced by 
 the nicotine deposit. (Compare Plate XI, fig. 2.) It may be 
 added, that the nicotine precipitate is very readily soluble in 
 excess of acetic acid, whereas the strychnine compound is sol- 
 uble with difficulty in this acid. 
 
 We have found, in repeated experiments, that the precipi- 
 tate produced by this reagent from quite impure solutions of 
 nicotine, will after a time yield characteristic crystals, even in 
 the midst of a dense deposit of foreign matter. Nevertheless, 
 it must be borne in mind, that under these circumstances, the 
 precipitate may fail to crystallise. In applying this test to 
 somewhat complex organic liquids, the precipitate should be 
 stirred and allowed to stand for at least an hour, with the occa- 
 sional addition of very small quantities of pure water to prevent 
 the deposit becoming dry, before it is fuUy concluded that crys- 
 tals will not form. 
 
 This is the most valuable test yet known for the detection 
 of nicotine, when in solution. 
 
 3. Carba^otic Acid. 
 
 An alcoholic solution of carbazotic, or picric, acid throws 
 down from aqueous solutions of nicotine, a yellow, amorphous 
 precipitate, which soon becomes a mass of crystalline tufts. It 
 is necessary to use large excess of the reagent, otherwise either 
 no deposit will form, or if produced it will soon disappear. 
 
 1. xoo" grain of nicotine, yields an immediate, yellow or green- 
 
 ish-yellow precipitate, which soon becomes a mass of 
 groups of yellow, crystalline tufts, Plate VI, fig. 3. 
 
 2. i.Joo grain : a rather copious precipitate, which soon crys- 
 
 tallises. 
 
 3. r u grain, yields a very good, crystalline precipitate. 
 
 28 
 
434 NICOTINE. 
 
 4. 4 0.0 grain, yields a just perceptible precipitate. 
 
 This reagent also throws down from solutions of the inor- 
 ganic alkalies, and of several of the other alkaloids, besides 
 nicotine, yellow precipitates which become crystalline. But, by 
 the aid of the microscope, the crystallised-nicotine compound 
 may generally be readily distinguished from all of these deposits 
 except that produced from very strong solutions of soda (Plate 
 I, fig. 6), which has frequently much the same crystalline form 
 as that assumed by the nicotine salt. Any doubt as to the true 
 nature of the deposit, may, of course, be readily removed by 
 the application of other reagents. 
 
 This reagent will often produce crystals with only the 10,- 
 000th part of a grain of nicotine, in one grain of water, in the 
 presence of foreign organic matter. But in mixtures of this 
 kind, the formation of crystals is more readily interfered with 
 than in the application of the preceding reagent. 
 
 4. Iodine in Iodide of Potassium. 
 
 This reagent may be prepared by dissolving three grains of 
 iodide of potassimn in one fluid drachm of distilled water, and 
 then adding one grain of pure iodine. A drop or two of this 
 mixture throws down from solutions of nicotine and of its salts, 
 a reddish-brown, brownish-yellow or yellowish, amorphous pre- 
 cipitate, its exact color depending somewhat upon the strength 
 of the alkaloidal solution, and also upon the quantity of reagent 
 added. After a little time, the precipitate may entirely disap- 
 pear ; but it is immediately reproduced upon further addition 
 of the reagent. The precipitate is readily soluble in caustic 
 potash and in alcohol. 
 
 1. -j-g-o grain of nicotine, in one grain of water, yields a very 
 
 copious deposit. 
 
 2. rroTo grain : a copious, reddish-brown precipitate. 
 
 3. 10,000 grain, yields a good, reddish-yellow deposit. 
 
 4. 2 5.0 C o grain : a quite distinct, greenish-yellow precipitate. 
 
 5. 3- 0.000 grain : a quite good turbidity. 
 
 6- 10 0% 00 grain : a very obvious turbidity. 
 
 7. 2-5-0% o(j grain, yields a perceptible cloudiness. 
 
CHLORIDE OF GOLD TEST. 435 
 
 As a solution of iodine in iodide of potassium causes no 
 precipitate in solutions of the inorganic alkalies and has its 
 color immediately discharged by them, it readily serves to dis- 
 tinguish nicotine from these substances. But, as the reagent 
 produces with most of the alkaloids and many other substances, 
 precipitates similar to that from nicotine, it has no positive 
 value, for the detection of this alkaloid, further than to confirm 
 the reactions of other tests. 
 
 From the fact that the limit of the reaction of this reagent 
 exceeds that of either of the other tests for nicotine, it is obvi- 
 ous that should this test fail to produce a precipitate, in a solu- 
 tion suspected to contain nicotine, it would be fruitless to apply 
 any of the other tests to the same solution, unless possibly there 
 should be some substance present that interfered with the reac- 
 tion of this reagent. 
 
 5. TercMoride of Gold. 
 
 This reagent produces in aqueous solutions of nicotine a yel- 
 low, amorphous precipitate, which is nearly insoluble in acetic 
 and hydrochloric acids, but soluble, to a clear solution, in ex- 
 cess of the caustic alkalies. 
 
 !• Too" grain of nicotine, yields an immediate, copious, yellow 
 precipitate, which remains amorphous ; the deposit is not 
 entirely soluble in several drops of strong acetic acid. If 
 several grains or more of the nicotine solution be precipi- 
 tated by the reagent and the mixture then heated, the 
 precipitate dissolves to a beautiful purple solution. 
 
 2. 1,000 grain, yields a good, yellow deposit, which is slowly 
 
 soluble in a few drops of a strong solution of potash. If 
 the precipitate produced from several grains of the solu- 
 tion be heated in the mixture, it dissolves, and is repro- 
 duced unchanged as the mixture cools. 
 
 3. 5,0 grain: an immediate, greenish-yellow precipitate, which 
 
 soon increases to a quite good, dirty-yellow deposit ; the 
 precipitate is readily soluble in a drop of potash solution. 
 
 4. 1 , u u grain, yields a good, yellowish precipitate, which im- 
 
 mediately disappears upon the addition of an alkali. 
 
436 NICOTINE. 
 
 5. 2 5,0 grain : in a few moments, a distinct turbidity, and in 
 
 a little time, a quite satisfactory precipitate. 
 6- 5- ,0 grain : in a little time, the mixture becomes turbid, 
 and soon there is a quite distinct deposit. 
 Terchloride of gold also produces yellow, amorphous precip- 
 itates with most of the alkaloids and various other substances. 
 
 6. Bromine in Bromohydric Acid. 
 
 Aqueous solutions of nicotine yield with a strong aqueous 
 solution of bromohydric acid saturated with bromine, a yellow 
 amorphous precipitate, which in a little time disappears. 
 1 • TW grain of nicotine, yields a copious, bright yellow precip- 
 itate, which soon disappears, but is reproduced upon fur- 
 ther addition of the reagent. 
 2. TToW grain : a rather copious precipitate. 
 3- 5,000 grain, yields a very good, greenish-yellow deposit, 
 which soon dissolves, and is not reproduced upon further 
 addition of the reagent. 
 4. 10,000 grain, yields a slight turbidity. 
 
 The reaction of this reagent is common to most of the alka- 
 loids and many other organic compounds. The reagent pro- 
 duces no precipitate and has its color discharged, when added 
 to solutions of the caustic alkahes. 
 
 7. Tannic Acid. 
 
 Tannic acid produces in aqueous solutions of nicotine a 
 white, amorphous precipitate, which readily dissolves to a clear 
 solution on the addition of a small quantity of hydrochloric 
 acid, but is reproduced upon farther addition of the acid, and 
 is then insoluble in large excess. The precipitate is readily 
 soluble in acetic and nitric acids, without being reproduced upon 
 further addition of the acid. 
 
 1 ■ JTo- grain of nicotine, in one grain of water, yields a copious 
 precipitate. 
 
 2. 1,000 grain : a good, bluish-white deposit. 
 
 3. T o.ooo grain : the mixture becomes slightly turbid. 
 
SEPARATION FROM ORGANIC MIXTURES. 437 
 
 This reagent also throws down white precipitates from solu- 
 tions of very many other substances. The behavior of the 
 nicotine precipitate with hydrochloric acid, however, is some- 
 what peculiar; 
 
 Other Reactions of Nicotine. — As nicotine has strong basic 
 properties, it, like the caustic alkalies, precipitates the oxides 
 of many of the metals from solutions of their salts. Nitrate 
 of suboxide of mercury throws down from somewhat strong 
 solutions of the free alkaloid, a copious, dirty-yellow precip- 
 itate, which almost immediately becomes brown, then nearly 
 black : this transition of color is due to the successive reduction 
 of the precipitated oxide of mercury. With one grain of a 
 5,000th solution of the alkaloid, this reagent produces a rather 
 good, dirty-white precipitate. 
 
 Sulphate of copper produces with aqueous solutions of the 
 alkaloid, when not too dilute, a bluish, flocculent precipitate of 
 the oxide of copper, which is insoluble in excess of nicotine. 
 The statement of some writers that this precipitate dissolves in 
 excess of the pure alkaloid to a blue solution, similar to that 
 formed by ammonia, is certainly erroneous. Solutions of salts 
 of lead, silver, nickel, cobalt, and several other metals, also 
 produce precipitates from somewhat strong solutions of the 
 alkaloid. A 100th solution of the poison yields with nitrate of 
 silver a quite good, white precipitate, which but very slowly 
 darkens upon exposure to sunlight. 
 
 Solutions of nicotine, even when concentrated, fail to yield a 
 precipitate with either sulphocyanide of potassium, the chromates 
 of potash, ferro- or ferri-cyanide of potassium, or gallic acid. 
 
 Separation from Organic Mixtures. 
 
 In suspected poisoning by tobacco, before proceeding to the 
 chemical examination for nicotine, the analyst should carefully 
 examine the suspected mixture or contents of the stomach, for 
 the presence of tobacco in its solid state. Any portions of the 
 plant thus found, separated from aU adhering matter, should be 
 carefully examined, by means of the microscope if necessary, 
 
438 NICOTINE. 
 
 in regard to their botanical characters, then digested at a gentle 
 heat in acidulated water, and the solution examined in the man- 
 ner just to be described. 
 
 Suspected Solutions and Contents of the Stomach. — The mix- 
 ture submitted for examination, diluted with distilled water if 
 necessary, is slightly acidulated with acetic acid and digested 
 for some little time at a moderate heat ; it is then allowed to 
 cool, the liquid strained through muslin, the solids on the mus- 
 lin washed with water and well pressed, and the united strained 
 liquids filtered. The clear liquid is now evaporated to a small 
 volume on a water-bath, then mixed with about an equal vol- 
 ume of strong alcohol, and the mixture gently warmed for some 
 minutes, with constant stirring ; the cooled liquid is again fil- 
 tered, and the filtrate evaporated on a water-bath to very near 
 dryness. Any nicotine originally present will now be in the 
 residue, in the form of acetate of the alkaloid. 
 
 This residue is gently warmed with about a fluid drachm or 
 even less of pure water, the mixture thoroughly stirred, trans- 
 ferred to a wet paper filter, and the filtrate collected in a stout 
 test-tube. The contents of the tube are now rendered alkaline 
 by a few drops of caustic soda or potash, when the nicotine will 
 be liberated from its saline combination, and perhaps emit its 
 peculiar odor. 
 
 The mixture is now violently shaken for some minutes with 
 about two volumes of chloroform or about five volumes of ether, 
 and this mixture allowed to repose, until the fluids have com- 
 pletely separated. In case chloroform has been used as the 
 solvent of the liberated alkaloid, the supernatant aqueous fluid 
 is removed by means of a pipette, the chloroform carefully de- 
 canted into another, perfectly dry test-tube, and from this into 
 a large watch-glass. By these decantations, any globules of 
 water which may have escaped removal by the pipette, may, 
 by care, be made to adhere to the sides of one or other of the 
 test-tubes. Should, however, globules of the alkaline aqueous 
 fluid have passed along with the chloroform into the watch- 
 glass, these must be removed before the latter liquid is evap- 
 orated to dryness, otherwise the residue will contain a trace of 
 soda or potash, which might subsequently interfere with some 
 
SEPARATION FROM ORGANIC MIXTURES. 439 
 
 of the tests for nicotine. The alkahne aqueous liquid removed 
 hj the pipette, is now washed with something less than its own 
 volume of fresh chloroform, and this, after repose, decanted and 
 added to the first chloroform extract. If ether has been em- 
 ployed as the solvent of the alkaloid, the aqueous fluid is 
 agitated a second time with two or three volumes of ether, 
 and the united ethereal liquids carefully collected in a large 
 watch-glass. 
 
 The contents of the watch-glass are now allowed to evapo- 
 rate spontaneously, in a cool place, when any nicotine present 
 wiU be left in the form of oily drops or streaks, having the 
 peculiar odor of the alkaloid, especially upon the application of 
 a very gentle heat. As the residue from extracts of this kind 
 has frequently a strong animal odor, this may more or less con- 
 ceal that of the poison. 
 
 If the residue thus obtained, indicates the presence of a 
 comparatively large quantity of the alkaloid, the contents of 
 the watch-glass are stirred with about half a drachm or more 
 of pure water, and the mixture, if it contains white, flocculent 
 masses or if turbid, transferred in small portions to a very small 
 moistened filter ; when the whole of the fluid has passed through, 
 the filter is washed with a few drops of water and this collected 
 with the first filtrate. If, on the other hand, the chloroform 
 residue fails to reveal any distinct evidence of the presence of 
 the alkaloid, only a few drops of water are used for its solution. 
 
 A drop of the clear liquid, transferred by means of a pipette 
 to a watch-glass, may now be treated with a small drop of cor- 
 rosive sublimate solution, the mixture allowed to stand quietly 
 for some little time, and then examined by the microscope. If 
 this examination indicates the presence of nicotine, other por- 
 tions of the clear liquid may be examined by bichloride of 
 platinum, carbazotic acid, and any of the other tests for this 
 alkaloid. If, however, the corrosive sublimate mixture fails to 
 yield crystals, it should ^e stirred with a glass rod, and allowed 
 to stand half an hour or longer. Should it still fail to yield any 
 evidence of the presence of the poison, the original liquid may 
 be concentrated, and then a drop examined by this reagent. 
 On the other hand, should this test as first applied, indicate the 
 
440 NICOTINE. 
 
 presence of much foreign matter, the original solution is again 
 extracted bj chloroform, this liquid evaporated to dryness, and 
 the residue treated as before. 
 
 By the method now considered, nicotine was detected in 
 very notable quantities in the stomachs of the first two cats 
 before referred to {ante, p. 426), each of which was killed by 
 a. single drop of the alkaloid placed in the mouth of the animal. 
 And by it we have also obtained perfectly satisfactory evidence 
 of the presence of the poison in an ounce of a very complex 
 organic mixture, to which only the 100th part of a grain of the 
 alkaloid had been added. 
 
 From the Tissues. — For the separation of absorbed nicotine 
 from the tissues, the solid organ, such as the liver, spleen or 
 lungs, is cut into very small shreds, then made into a thin 
 paste with water, the mixture acidulated with acetic acid, and 
 digested, with frequent stirring, for some time at a very gentle 
 heat. The cooled mixture is then treated after the same 
 manner as before described, for the examination of suspected 
 solutions. 
 
 As the quantity of the alkaloid present in the tissues, in 
 poisoning by this substance, is at most extremely small, the resi- 
 due obtained from the chloroform extract, should be treated with 
 only a few drops of water and great care exercised in the prep- 
 aration of this solution for the application of the different tests. 
 
 M. Stas was, perhaps, the first to show that nicotine was 
 absorbed and might be separated from the tissues in its un- 
 changed state. The same fact was also pointed out about the 
 same time by Orfila. This observer cites several instances 
 (Toxicologic, 1852, ii, 493), in which he obtained the poison 
 from the liver and spleen of dogs killed by from fifteen to 
 twenty drops of the alkaloid. 
 
 From the Blood. — Nicotine, when present in the blood, may 
 be recovered by acidulating the liquid with about five drops of 
 strong acetic acid for each ounce of fluid, and agitating it in a 
 closed bottle with about its own volume or more of a mixture 
 of equal parts of water and alcohol, until the whole becomes 
 perfectly homogeneous. The mixture is then digested at a mod- 
 erate heat, with frequent stirring, until the albuminous matter 
 
SEPARATION FROM ORGANIC MIXTURES. 441 
 
 present collects into small, brownish flakes. The cooled liquid 
 is strained through wet muslin, and the solid residue washed 
 and strongly pressed. If the liquid is still turbid, it is passed 
 through the strainer a second or even a third time. The fluid 
 is now evaporated at a moderate heat on a water-bath to about 
 half its volume, and while still warm, mixed with a little strong 
 alcohol, and the reddish-brown, coagulated matter removed by 
 a muslin filter. When the quantity of blood operated upon is 
 comparatively small, the strained liquid thus obtained is usually 
 clear and has only a slight yellow color ; but when a large 
 amount of the fluid is examined, the strained liquid is generally 
 turbid and highly colored. Under these circumstances, it may 
 be passed through a wet paper filter. 
 
 The liquid is now slowly evaporated on a water-bath to near 
 dryness. If during the concentration, much solid matter sepa- 
 rates, it should be removed by a small filter. The nearly dry 
 residue is stirred with about half a drachm of water, the solu- 
 tion filtered, the filtrate rendered alkaline by caustic soda, and 
 extracted by chjoroform in the usual manner. The chloroform 
 residue is well stirred with a few drops of water, and, the liquid 
 carefully separated from any flakes of animal matter present, 
 either by means of a pipette or by a very small filter. The 
 liquid is then examined by the ordinary reagents. 
 
 By the above method, perfectly satisfactory evidence of the 
 presence of . nicotine was obtained from one ounce of healthy 
 blood to which the 100th part of a grain of the alkaloid had 
 been purposely added — the dilution being one part of the poison 
 in about 50,000 parts of the fluid. 
 
 In the case of the second of the three cats before referred 
 to — in which a small drop of nicotine proved fatal in two min- 
 utes and a half — seven fluid drachms of blood wei'e recovered 
 from the body immediately after death ; five drachms of the 
 liquid were then treated after the above method, and the final 
 aqueous solution reduced to three drops. One drop of this mix- 
 ture when treated with corrosive sublimate, gave, after a little 
 time, perfectly satisfactory evidence of the presence of nico- 
 tine, it yielding about twenty large groups of crystals similar to 
 those shown in Plate VI, fig. 2. A second drop, treated with 
 
442 NICOTINE. 
 
 carbazotic acid, also furnished a fine deposit of characteristic 
 crystals. The third drop, when treated with bichloride of pla- 
 tinum, gave a slight precipitate, but no crystals were obtained. 
 
 From the third cat — which was killed in seventy-five seconds 
 by a drop of the alkaloid — ten fluid drachms of blood were 
 obtained with the greatest possible speed and care, and then 
 treated as before shown, excepting that a drop of sulphuric acid 
 was used as the acidifying agent and ether for the extraction of 
 the poison. The final solution, when reduced to two drops, gave 
 with corrosive sublimate, and carbazotic acid, perfectly satisfac- 
 tory evidence of the presence of the alkaloid ; but at the same 
 time, indicated that it was present in smaller quantity than in 
 the preceding case. This case shows the extreme rapidity with 
 which this poison may enter the circulation. 
 
 It is a singular fact, that the chloroform and ether residues in 
 both the foregoing cases possessed in a very marked degree, the 
 peculiar ethereal odor of the pure alkaloid administered ; whilst 
 in another case, in which the poisoning was occasioned by ^n 
 extract of tobacco, the chloroform residue obtained in precisely 
 the same manner, had the acrid tobacco odor usually observed 
 in commercial samples of nicotine. 
 
 In the examination of organic mixtures for the separation of 
 nicotine, it has heretofore been usual for analysts to advise either 
 oxalic, tartaric, or sulphuric acid as the acidifying agent. But, 
 we have not found that either of these acids possess, for this 
 purpose, any advantage over acetic acid, and on the whole pre- 
 fer the latter. If sulphuric acid be employed, no more should 
 be added than just sufficient to give the mixture a very slight 
 acid reaction. It may here be remarked that anhydrous acetate 
 of nicotine is more or less volatilised by continued heating on a 
 water -bath ; and, also, that this salt is soluble to a notable ex- 
 tent in ether. < 
 
 For the separation of the liquid alkaloids, nicotine and co- 
 nine, from organic mixtures, the following method, based upon 
 the volatility of these alkaloids, has been proposed. The mix- 
 ture, acidified with from ten to twenty grains of oxalic or 
 tartaric acid, is treated with about twice its weight of strong 
 
CONINE. 443 
 
 alcohol and heated to about 150° F., the cooled liquid strained, 
 the residue washed with alcohol and pressed. The extract thus 
 obtained, is concentrated at a gentle heat, the resulting aqueous 
 solution separated by filtration from any insoluble matter pres- 
 ent, then rendered alkaline by caustic potash or soda, and dis- 
 tilled to very near dryness, in a retort provided with a proper 
 receiver : the residue in the retort may be treated with a little 
 water and again distilled, the product being received with the 
 first distillate. The alkaloid will now be present in the distillate. 
 
 This liquid may either be agitated with several volumes of 
 ether, the ethereal solution decanted, and the operation repeated 
 with fresh portions of ether, until a drop of this fluid upon 
 spontaneous evaporation no longer leaves a residue of the alka- 
 loid ; the mixed ethereal solutions are then evaporated sponta- 
 neously at a low temperature, and the residue placed for a few 
 moments over sulphuric acid under a glass receiver. Or, the 
 distillate may be neutralised with oxalic acid, concentrated at 
 a low temperature to a small volume, the residual liquid ren- 
 dered alkaline by potash or soda, and the alkaloid then ex- 
 tracted by ether. Chloroform might, of course, be substituted 
 for ether in either of these processes. 
 
 Since this method, by distillation, is always attended with a 
 quite notable loss of the alkaloid, it is not as well adapted for 
 the detection of very minute quantities of the poison, as the 
 method before considered. 
 
 Section II. — Conine. (Conium Maculatum.) 
 
 History. — Conine, known also as conicine, conia, and coni- 
 cina, is the active principle of Conium maculatum, or common 
 hemlock. It exists, in the form of an organic salt, perhaps in 
 all parts of the plant, but is most abundant in the fruit. The 
 relative quantity of the alkaloid present in the plant varies 
 with the growth of the latter : according to Geiger, six pounds 
 of the fresh, green, unripe seeds, or nine pounds of dry, ripe 
 seeds, yield one ounce of conine. This alkaloid was first ob- 
 tained as an impure sulphate by Giseke, in 1827; Geiger, in 
 
444 CONINE. 
 
 1831, obtained it in its pure state, and described some of its 
 properties and effects upon animals. Its effects upon animals 
 were more fully examined, in 1835, by Dr. Christison. In re- 
 gard to its composition, four different formulae have been ad- 
 vanced, namely : Ci2Hi4NO, by Liebig ; C17H17N, by Blyth ; 
 CieHijN, by Ortigosa ; and CisHuN, by Gerhardt. The formula 
 of Grerhardt is the one usually adopted. 
 
 Preparation. — Conine may be obtained, according to Dr. 
 Christison, by exhausting the ripe seeds of hemlock with alco- 
 hol, distilling off the alcohol, mixing the residual syrup with an 
 equal volume of water and a little hydrate of potash, distilling 
 the mixture in a chloride of calcium-bath and collecting the dis- 
 tillate in a proper receiver. The conine passes over with the 
 water and yields an aqueous solution of the alkaloid, containing 
 oily drops floating upon its surface. If the conine contains am- 
 monia, this may be removed by placing the mixture in vacuo 
 over sulphuric acid, when the gas will escape in the form of 
 bubbles. 
 
 Conine is a most virulent poison, almost equaling in the 
 activity of its action hydrocyanic acid. As yet there seems to 
 be only a single recorded case of poisoning in the human sub- 
 ject, by this substance in its pure state (Arch, der Pharma., 
 Sept., 1861, p. 257) ; but, poisoning by hemlock is of not un- 
 frequent occurrence. Most of these cases have resulted from 
 the mistaking of hemlock for other plants. 
 
 Symptoms. — The symptoms occasioned by hemlock are sub- 
 ject to considerable variation, as may be seen from the following 
 cases. In an instance related by Dr. Haaf, a soldier having 
 eaten some sotip containing hemlock leaves, soon fell asleep : in 
 an hour and a half afterwards, he was insensible and breathed 
 with difficulty ; his pulse was slow and hard ; the extremities 
 cold ; and the face bluish, and distended with blood, like that 
 of a person strangulated. An emetic of tartarised antimony 
 was then administered, but it only produced vain efforts to 
 vomit. He complained of being cold, and soon again lost the 
 power of speech and consciousness, and died in about three 
 hours after taking the poison. (Orfila's Toxicology, vol. ii, p. 
 537.) In a case quoted by Dr. A. Stills (Mat. Med., vol. ii, 
 
PHYSIOLOGICAL EFFECTS. 445 
 
 p. 268), a man, who took ten drachms of an extract of hem- 
 lock, experienced great restlessness and anxiety, dropped insen- 
 sible from his chair, had convulsions, and expired in two hours 
 after taking the dose. Dr. Christison relates a case (Op. cit., 
 657), in which an old woman swallowed two ounces of a strong 
 infusion of hemlock leaves with the same quantity of whisky, 
 and died an hour afterwards, comatose and convulsed. 
 
 The following case is reported by Dr. J. H. Bennett (Edin. 
 Med. and Surg. Jour., July, 1845, p. 169). A man ate a large 
 quantity of hemlock, believing it to be parsley. He soon after- 
 wards lost the power of walking, staggered, and finally fell, but 
 still retained his consciousness and intelligence. In about two 
 hours after taking the poison, there was complete paralysis of 
 the upper and lower extremities, with occasional spasmodic 
 movements of the left leg ; and the patient had lost the power 
 of sight, deglutition and speech, but was still sensible ;• his pulse 
 and breathing were natural. The pupils became fixed, the ac- 
 tion of the heart very feeble, and death ensued in about three 
 hours and a quarter after the poison had been taken. In a case 
 quoted by Dr. Pereira (Mat. Med., ii, 732), an overdose of this 
 plant also produced general paralysis : the under jaw fell, the 
 saliva ran from the mouth, the urine dropped from the bladder, 
 and the contents of the rectum were discharged. The patient 
 continued for nearly an hour in this condition, unable to move 
 or to command the slightest muscular exertion, though all the 
 time perfectly sensible ; but under the use of stimulants, he 
 finally recovered. 
 
 Conine, when administered in its pure state, according to 
 the experiments of Dr. Christison, acts at first as a locaL irri- 
 tant ; but its local effects are quickly followed by general palsy 
 of the muscles, afi"ecting first those of voluntary motion, then 
 the respiratory muscles of the chest and abdomen, and lastly 
 the diaphragm, ending in death by asphyxia. In some cases, 
 convidsive tremors were observed. The heart continued to pul- 
 sate after other signs of life had ceased. In no case, did the 
 external senses seem to be afifected until respiration was im- 
 paired. This observer states, that a single drop of the alkaloid, 
 applied to the eye of a rabbit, killed it in nine minutes ; and 
 
446 CONINE. 
 
 three drops, applied in the same manner, killed a strong cat in 
 a minute and a half. Five drops, introduced into the throat of 
 a small dog, began to act in thirty seconds, and proved fatal in 
 one minute ; and two grains of the chloride, injected into the 
 femoral vein of a young dog, killed it before there was time to 
 note the interval. (On Poisons, p. 655.) 
 
 The following results were observed in some of our own ex- 
 periments, with the pure alkaloid. A single drop of the alkaloid 
 was placed upon the tongue of a large and healthy cat. In a 
 few seconds, the animal was inclined to stand still, and mani- 
 fested an unsteady gait when disturbed ; in two minutes and a 
 half, it fell on its right side, then voided urine, had violent con- 
 vulsive movements of the limbs and a tremulous motion of all 
 parts of the body, and was dead in three minutes after the poi- 
 son had been administered. In another experiment, the animal 
 being immediately placed upon its feet, stood perfectly still, and 
 the pupils of the eyes became dilated and insensible ; in forty- 
 five seconds, the legs of the animal became powerless and it 
 sank upon its abdomen, then passed urine, had violent spasms 
 of the extremities, and died in four minutes after the exhibition 
 of the poison. 
 
 Treatment. — The treatment in poisoning by hemlock, is 
 much the same as that already pointed out for an overdose of 
 tobacco [ante, p. 427). As an emetic, mustard has been strongly 
 advised. Dr. Pereira was of the opinion that strychnine might 
 be found beneficial, on account of its opposite physiological 
 effects to those of conine. 
 
 PoST-MOETEM AppEAEANCES. — There is generally more or 
 less venous congestion, especially in the brain, and a fluid con- 
 dition of the blood. In the case reported by Dr. Haaf, the 
 stomach was found half fiUed with undigested matters, and 
 there were some red spots around the pylorus. The intes- 
 tines were natural ; and the vena cava and heart empty, but 
 all the vessels of the brain were highly gorged with liquid 
 blood. In the case examined by Dr. Christison, in which 
 death took place in an hour, the vessels of the brain were 
 not particularly turgid, but the blood throughout the body was 
 remarkably fluid. 
 
CHEMICAL PROPERTIES. 447 
 
 In Dr. Bennett's case, sixty-three hours after death, an un- 
 usual quantity of fluid blood was found in the vessels of the 
 scalp, and in the sinuses of the brain ; with slight serous effu- 
 sion beneath the arachnoid membrane, and into the ventricles, 
 and numerous bloody points in the substance of the brain. The 
 lungs were gorged with dark-red, fluid blood. The blood, 
 throughout the body, was of a dark color and fluid. The 
 stomach contained a pultaceous, vegetable mass ; and the mu- 
 cous membrane was much congested, especially at its cardiac 
 extremity. The intestines and other viscera were healthy, but 
 partially congested. On examining the contents of the stomach, 
 they were found to contain fragments of leaves of the Conium 
 maculatum, which on being bruised in a mortar, with a solution 
 of caustic potash, evolved the peculiar mousy odor of conine. 
 
 Chemical Properties. 
 
 General Chemical Nature. — Conine, in its perfectly pure 
 state, is a colorless, transparent, oily liquid, having a strong 
 alkaline reaction, and, according to Blyth, a specific gravity of 
 0'87 ; it has a peculiar, repulsive and suffocating odor, resem- 
 bling somewhat that of a long-used tobacco-pipe. When the 
 alkaloid is diluted with water, it emits an odor similar to that 
 of mice. This pecuKar odor is perceptible even in highly 
 diluted solutions : a few drops of a pure aqueous solution con- 
 taining only the 50,000th part of its weight of the free alkaloid, 
 when inclosed for a little time in a small test-tube, imparts its 
 odor, in a very marked degree, to the contained air. 
 
 Conine imparts a transient, greasy stain to white paper, and 
 burns with a bright, smoky flame ; its taste is repulsive and 
 persistent. Its boiling point is about 350° F., but it distills 
 with the vapor of water at 212°, with, however, partial decom- 
 position. The more rapidly it is distilled, the less decomposi- 
 tion it suffers. When heated in an atmosphere of hydrogen 
 gas, it may be distilled without change. When preserved from 
 the action of the air, it remains colorless, but upon exposure, 
 it becomes yellow, then brownish, and it is finally resolved into 
 a brownish resin and ammonia. 
 
448 CONINE. 
 
 Solubility. — According to Geiger, with whose observation 
 our own closely agrees, conine dissolves at ordinary tempera- 
 tures in about one hundred parts of pure water; its aqueous 
 solutions, when not too dilute, have a strongly alkaline reaction. 
 When excess of conine is agitated with water, it divides into 
 minute drops and gives the mixture a milky appearance ; on 
 repose, the excess of the alkaloid collects on the surface of the 
 water, as an oily layer. It is very soluble in alcohol, ether, 
 and in chloroform. Both ether and chloroform readily separate 
 the alkaloid from its aqueous solutions, and upon spontaneous 
 evaporation leave it in the form of oily drops ; the former of 
 these liquids separates the poison from water much more readily 
 than it does in the case of nicotine. 
 
 1. Extraction by Ether. — When a 100th aqueous solution of 
 free conine is agitated with Jive volumes of ether, and this fluid 
 decanted, the aqueous liquid is reduced to about a 4,000th solu- 
 tion of the poison. Under these circumstances, therefore, ether 
 extracts about 39-40ths of the alkaloid. 
 
 2. By Chloroform. — When a 100th solution of the free poi- 
 son is agitated with five volumes of chloroform, the aqueous 
 solution is reduced to about the same extent as when treated 
 under similar circumstances with ether. 
 
 Special Chemical Properties. — Exposed to the vapors of 
 volatile acids, conine gives rise to dense white fumes. It neu- 
 tralises acids completely, forming odorless salts, but few of which 
 have been obtained in the crystalline state. The conine used 
 in the present investigations was freshly prepared, had a just 
 perceptible yellowish tint, and was perfectly free from ammonia : 
 at least Nessler's test, which will indicate the presence of am- 
 monia in a few drops of a 500,000th solution of the alkali, failed 
 to indicate its presence in a saturated aqueous solution of the 
 alkaloid. 
 
 If a drop of the alkaloid be placed in a watch-glass and 
 covered by an inverted watch-glass containing a drop of hydro- 
 chloric acid, the glasses immediately become filled with dense, 
 white fumes, and the drop of conine very soon solidifies to a 
 mass of beautifal, crystalline needles, Plate VI, fig. 4 ; after a 
 time, similar crystals form in the hydrochloric acid drop. When 
 
SPECIAL CHEMICAL PROPERTIES. 449 
 
 diluted solutions of the alkaloid are exposed to the vapor of 
 hydrochloric acid, they also give rise to white fumes, and the 
 Conine solution when concentrated spontaneously deposits crys- 
 taUine needles of chloride of conine. The same crystals are 
 obtained by neutralising an aqueous solution of the alkaloid with 
 the diluted acid, and allowing the mixture to evaporate sponta- 
 neously. The crystals of chloride of conine are permanent in 
 the air : the statement of some writers that they are deliques- 
 cent, is erroneous. 
 
 When strong hydrochloric acid is brought in contact with 
 pure conine, the mixture assumes a pale red color, which in- 
 creases in intensity, and after a time becomes nearly blood-red ; 
 if the mixture be evaporated spontaneously to near dryness, it 
 deposits a mass of long, crystalline needles, which are readily 
 soluble in water and in alcohol, and redeposited as the liquid 
 evaporates. 
 
 An aqueous solution of conine, when treated with a saturated 
 solution of chlorine gas, becomes turbid. A drop of a 100th 
 solution, yields in this manner, a dense, white turbidity ; the 
 same quantity of a 1,000th solution, yields after a time, a 
 slight cloudiness. 
 
 Nitric acid exposed to the vapor of conine gives rise to 
 dense, white fumes. When the alkaloid is treated directly with 
 excess of the acid, it yields after a little time, a pale red mix- 
 ture, which after a few days becomes converted into a deep red 
 liquid containing a mass of colorless, crystalline needles. 
 
 Sulphuric acid forms with the pure alkaloid a pale red liquid, 
 which after a few days, deposits crystalline needles along the 
 margin of the mixture. If a sulphuric acid solution of the 
 alkaloid or of any of its salts, be treated with a small crystal of 
 bichromate of potash, the mixture upon being stirred, slowly 
 assumes a green color, due to the formation of sesquioxide of 
 chromium. 
 
 Upon neutralising pure conine or its aqueous solution with 
 oxalic acid, the mixture upon spontaneous evaporation, yields 
 prismatic crystals of the oxalate of conia. If the mixture be 
 evaporated in a water-bath, the salt is left in the form of a 
 gummy mass. 
 
 29 
 
450 CONINE. 
 
 Most of the salts of conine are soluble in water and in alco- 
 hol, but nearly or altogether insoluble in ether. When their 
 aqueous solutions are treated with a mineral alkali, the alkaloid 
 is liberated and emits its peculiar odor ; from somewhat strong 
 solutions of its salts, the alkaloid separates in the form of minute 
 drops, which finally collect upon the surface of the mixture as 
 an oily layer. On distilling an aqueous mixture of a salt of 
 conine and caustic potash or soda, the liberated alkaloid passes 
 over with the distillate. If the distillate be neutralised with 
 oxalic acid, evaporated to dryness, and the residue digested 
 with alcohol, the oxalate of conia will dissolve, while any oxa- 
 late of ammonia present wiU remain, it being insoluble in this 
 menstruum. 
 
 In the examination of the following tests for conine when 
 in solution, the pure alkaloid was dissolved in distilled water. 
 When a solution of this kind is agitated it forms a very frothy 
 liquid, even when the mixture contains only the 10,000th part 
 of its weight of the poison. The fractions indicate the frac- 
 tional part of a grain of the alkaloid in solution in one grain of 
 water. Unless otherwise stated, the results refer to the reac- 
 tions of one grain of the solution. 
 
 1. Terchloride of Gold. 
 
 A saturated aqueous solution of conine yields with excess of 
 terchloride of gold a copious, bright yeUow, amorphous precip- 
 itate, which is insoluble in acetic acid and in diluted hydrochlo- 
 ric acid ; with a less quantity of reagent, the precipitate has a 
 brownish or reddish-brown color. When treated with potash, 
 the precipitate assumes a dark color and finally becomes nearly 
 black. 
 
 1. i-g-u grain of conine, in one grain of water, yields a quite 
 
 copious precipitate. 
 
 2. -aw grain : a quite good, yellow deposit. 
 
 3- 1,000 grain : an immediate cloudiness, and soon a very satis- 
 factory, yellow precipitate. 
 
 4. 5 , o' grain, gives but Httle indication of the presence of the 
 alkaloid, even after the mixture has stood for some time. 
 
IODINE TEST. 451 
 
 There was a failure to obtain crystals from any of the fore- 
 going mixtures. 
 
 2. Carbasotic Acid. 
 
 Strong aqueous solutions of conine, yield with an alcoholic 
 solution of carbazotic acid a yellow, amorphous precipitate, 
 which in a little time, changes into microscopic globules, and 
 these after a time, deposit large, yellow crystals. The precip- 
 itate is insoluble in excess of the reagent, but readily soluble 
 in excess of the alkaloid, and also in acetic acid. 
 
 1- ToTT grain of conine, yields a copious precipitate, which soon 
 
 becomes crystalline, Plate VI, fig. 5. If the mixture be 
 stirred with a glass rod, it immediately yields streaks of 
 granules and small crystals. 
 
 2. 5-00" gf'ain : an immediate cloudiness, and in a little time, a 
 
 quite good, yeUow amorphous deposit. 
 
 3. 1,000 grain, yields but little indication of the presence of the 
 
 alkaloid. 
 
 3. Corrosive Sublimate. 
 
 This reagent produces in aqueous solutions of conine a 
 white, curdy precipitate, which is but sparingly soluble in 
 water, but readily soluble in acetic and the mineral acids. 
 1. xo~o grain of conine, yields a copious, white precipitate, which 
 does not change in color, and remains amorphous. 
 
 2- Too' grain, yields an immediate turbidity, and soon, a good 
 
 deposit. 
 
 3- 1,000 grain, yields in a few moments, a distinct cloudiness, 
 
 and in a little time, the mixture becomes quite turbid. 
 
 4. Iodine in Iodide of Potassium. 
 
 A solution of iodine in an aqueous solution of iodide of po- 
 tassium produces in solutions of conine, an immediate, reddish- 
 brown, amorphous precipitate, which soon turns yellow, then 
 dissolves to a clear solution ; upon further addition of the re- 
 agent, the precipitate may be reproduced, even several times, 
 from somewhat strong solutions of the alkaloid. If a very large 
 
452 CONINE. 
 
 excess of the reagent be at first added, the precipitate is per- 
 manent. It is readily soluble in acetic acid. 
 !■ To7 grain of conine, yields a very copious precipitate. 
 2. r,^"o grain : a copious deposit. 
 3- TuToo'o grain : a very good, brownish-yellow precipitate. 
 
 4. 2 5,0 grain: a very satisfactory, yellowish deposit. 
 
 5. 5 0,0 grain, yields a quite good, yellowish turbidity. 
 
 6. 10 0% grain : a distinct turbidity. 
 
 5. Bromine in BromoJiydric Acid. 
 
 If a small drop of anhydrous conine be placed in a watch- 
 glass, and this covered by an inverted glass containing a drop 
 of an aqueous solution of bromohydric acid saturated with bro- 
 mine, the glasses become fiUed with dense, white fumes, and 
 soon crystalline needles form in the conine drop, and this on 
 spontaneous evaporation of the liquid leaves a mass of long, 
 colorless needles; the drop of reagent also leaves on spontane- 
 ous evaporation, a very good deposit of similar crystals. When 
 an aqueous solution of the alkaloid is exposed to the vapor of 
 the reagent, it also evolves white fumes, even when the solution 
 contains only the 1,000th of its weight of conine. 
 
 On treating anhydrous conine directly with the above re- 
 agent, it yields a yellow, amorphous mass, which soon becomes 
 converted into large, orange-colored globules ; these soon be- 
 come yeUow, and after a time, deposit colorless, prismatic crys- 
 tals. If the mixture be evaporated spontaneously, it leaves a 
 mass of large, crystalluie needles, which are readily soluble in 
 alcohol, and reproduced as this liquid evaporates. These reac- 
 tions, however, are modified somewhat by the relative quantities 
 of conine and the reagent present. 
 
 When the reagent is added to an aqueous solution of the 
 alkaloid, it produces a yellow, amorphous precipitate, which 
 after a time changes into oil-like globules ; upon further addi- 
 tion of the reagent, the yellow, amorphous precipitate is repro- 
 duced. On allowing the mixture to evaporate spontaneously, 
 it sometimes leaves a crystalline residue, whilst at others a 
 gummy mass, the result depending upon the relative quantity 
 
NITRATE OF SILVER TEST. 453 
 
 of reagent present. The precipitate is readily soluble in acids, 
 
 even in acetic acid. 
 
 !• To"o" grain of conine, in one grain of water, when exposed to 
 the vapor of the reagent, yields after a time, a deposit of 
 crystalline needles ; if this mixture be allowed to evapo- 
 rate, it leaves a mass of similar crystals. When the conine 
 solution is treated directly with the reagent, it yields a 
 copious, yellow precipitate, which soon becomes converted 
 into oily globules. If large excess of the reagent has been 
 avoided, the mixture on spontaneous evaporation leaves a 
 mass of crystals. 
 
 2- T7oo"o grain, yields with the reagent, a copious, yellow de- 
 posit, which soon dissolves, but is reproduced upon further 
 addition of the reagent. 
 
 3. 5,0 grain : a good,_ yellowish deposit. 
 
 ^- r o.ooo grain, yields a very distinct precipitate, which soon 
 dissolves, and is not reproduced upon further addition of 
 the reagent. 
 
 6. Nitrate of Silver. 
 
 When an aqueous solution of conine is treated with a solu- 
 tion of nitrate of silver, it yields a brownish precipitate of pro- 
 toxide of silver, which soon becomes converted into the suboxide 
 of the metal, having a nearly black color. 
 !• Too" grain of conine, yields a quite good deposit. 
 
 2. 1,000 grain : an immediate precipitate, and in a little time, a 
 
 good, flocculent deposit. 
 
 3. S-.W0 grain: a slight cloudiness, and in a little time, a quite 
 
 fair deposit. 
 
 4. 10,0 grain : after some minutes, the mixture presents a 
 
 slight cloudiness. 
 
 7. Tannic Acid. 
 
 This reagent produces in aqueous solutions of conine a 
 white, amorphous precipitate, which is readily soluble in a small 
 quantity of hydrochloric acid, but again reproduced upon fur- 
 ther addition of the acid and then is insoluble in large excess. 
 
454 CONINE. 
 
 The precipitate is permanently soluble in acetic and nitric acids, 
 as also in excess of the conine solution. 
 
 1- Too grain of conine, yields a copious precipitate. 
 
 2- ],ooo grain : a quite good precipitate. 
 
 3- To7o~oo grain : the mixture becomes slightly turbid. 
 
 Other Reagents. — As conine has strong basic properties, it 
 precipitates the oxides of several of the metals from solutions of 
 their salts. Nitrate of suboxide of mercury produces in strong 
 aqueous solutions of the alkaloid a dirty-brown precipitate, 
 which soon becomes nearly black. One grain of a 100th solu- 
 tion of the alkaloid, yields a very copious deposit ; the same 
 quantity of a 1,000th solution, yields a good, yellowish-white, 
 and a 5,000th solution, a dirty-white precipitate. Acetate of 
 lead produces \in a 100th solution of the alkaloid, a quite good, 
 white deposit. Sulphate of copper gives a bluish precipitate, 
 which is insoluble in excess of the conine solution. 
 
 A saturated aqueous solution of conine yields no precipitate 
 with either bichloride of platinum, iodide of potassium, chromate 
 or bichromate of potash, ferro- or ferricyanide of potassium, or 
 with ammonio-sulphate of copper. Should the alkaloid con- 
 tain ammonia, as is often the case, it may of course, when 
 treated with bichloride of platinum, yield a yellow precipi- 
 tate of the double chloride of platinum and ammonium ; but 
 the corresponding salt of conine is freely soluble in water, in 
 which respect this alkaloid differs from nicotine. The' state- 
 ment of Orfila, that acetate of lead produces no precipitate 
 with conine, is only true of somewhat dilute solutions of the 
 alkaloid. 
 
 Fallacies. — An affirmative reaction of none of the above 
 tests for conine in solution, when taken alone, is characteristic 
 of this alkaloid, since each of them produces similar results with 
 solutions of various other substances. But, by the concurrent 
 action of two or more of these tests, especially %vhen taken in 
 connection with the odor and physical state of conine, the pres- 
 ence of the alkaloid, even in minute quantity, may be determ- 
 ined with certainty. 
 
SEPARATION FROM ORGANIC MIXTURES. 455 
 
 Conine and nicotine are distinguished from other alkaloids, 
 in being liquid at ordinary temperatures, by their peculiar odor, 
 and in that when their aqueous solutions or solutions of their 
 salts previously mixed with a fixed alkali, are distilled, they 
 appear in the distillate and impart to it, at least after concen- 
 tration, an alkaline reaction. In this connection, however, it 
 must be borne in mind that on distilling a mixture containing 
 ammonia, this alkali will also appear in the distillate and impart 
 to it an alkaline reaction ; but this substance is readily distin- 
 guished, even by its odor, from the volatile alkaloids. 
 
 Conine is distinguished from nicotine : 1. By its peculiar 
 odor, which is characteristic even in highly diluted solutions ; 
 2. Its sparing solubility in water ; 3. In yielding crystalline 
 needles when exposed to the vapor or treated directly with 
 hydrochloric acid ; 4. By yielding a white precipitate with cor- 
 rosive sublimate, which remains amorphous and unchanged in 
 color; 5. By its behavior with carbazotic acid; 6. Its behavior 
 with bromine in bromohydric acid ; 7. In giving a dark-brown 
 precipitate with nitrate of silver ; and, 8. By failing to yield 
 a precipitate with bichloride of platinum. On comparing the 
 special reactions of these alkaloids, as already detailed, other 
 differences will be observed. 
 
 A solution of conine may be distinguished from ammonia in 
 the same manner as already pointed out for distinguishing this 
 alkali from nicotine in the special reactions of the latter. 
 
 Sepaeation from Organic Mixtures. 
 
 If, in poisoning by hemlock, any solid parts of the plant are 
 found, they may, sometimes, be identified by their botanical 
 characters (See Pereira's Mat. Med., vol. ii, p. 727), and by 
 evolving the peculiar odor of conine, when moistened with a 
 solution of potash and bruised in a mortar. 
 
 Conine may be recovered from organic solutions, the con- 
 tents of the stomach, the tissues, and from the blood, in pre- 
 cisely the same manner as already pointed out for the recovery 
 of nicotine. Since most of the salts of conine are not altogether 
 insoluble in ether, if this liquid be employed for the separation 
 
456 CONINE. 
 
 of foreign organic matter from- an aqueous solution of a salt of 
 this kind, the decanted ether should be reserved for future ex- 
 amination, if necessary. 
 
 A fluid ounce of blood taken from each of the two cats 
 before referred to — each of which was killed by a single drop 
 of conine. — was examined after the method pursued in the 
 investigation of the blood from the cats poisoned by nicotine, 
 as already described. The final solution from the blood of both 
 animals, when reduced to three drops and tested by its odor 
 and three different reagents, gave results, which, knowing all 
 the circumstances, there is no doubt were due to the presence 
 of conine ; yet, in an unknown case, the results would by no 
 means have justified the assertion that the poison was certainly 
 present. On mixing the 100th part of a grain of conine with 
 an ounce of normal blood, and pursuing the above method of 
 analysis, the results were equivocal ; but when the 25th of a 
 grain of the poison was added, the results were quite satisfac- 
 tory. From a comparison of the special tests for conine and 
 nicotine, it is quite obvious that they will indicate with cer- 
 tainty the presence of a much smaller quantity of the latter 
 than of the former alkaloid. 
 
OPIUM. 457 
 
 CHAPTER II. 
 
 OPIUM AND SOME OF ITS CONSTITUENTS. 
 
 I. Opium. 
 
 History and Chemical Nature. — This substance is the con- 
 crete juice of the Papaver somniferum, or white poppy, and is 
 obtained by making incisions into the capsules when in their 
 unripe state. In regard to its chemical nature, opium is ex- 
 tremely complex; and its composition varies somewhat in the 
 several commercial varieties. Thus, besides gum, resin, color- 
 ing matter, and inorganic substances, it contains, according to 
 some observers, not less than twelve crystallisable organic prin- 
 ciples. Of these, the only ones that will be separately noticed 
 at present are, the alkaloids morphine^ narcotine, codeine, and 
 narceine, the neutral substance opianyl, or nieconin, and the 
 organic acid, meconic. 
 
 The poisonous properties of opium are due chiefly to the 
 morphine which it contains, which is present principally in com- 
 bination with meconic acid, as meconate of the alkaloid. Of 
 the several varieties of opium, the Smyrna is usually regarded 
 as containing the greatest proportion of morphine. From the 
 best samples of this variety, Merck obtained thirteen per cent, 
 or more, of the alkaloid, while from the poorest, he obtained 
 only from three to four per cent. On an average, perhaps, 
 opium as found in the shops contains from six to eight per 
 cent, of the poison. 
 
 This drug is sometimes taken as a poison in its solid state, 
 but more frequently in the form of Laudanum, or Tincture of 
 opium, which is an alcoholic solution of the drug. The me- 
 dicinal dose of opium in its solid form for an adult, varies, 
 according to circumstances, from half a grain to five grains ; 
 the dose of the tincture, under like circumstances, varies from 
 
458 OPIUM. 
 
 ten minims to one fluid drachm. According to the formulae of 
 most of the Pharmacopoeias, about thirteen minims or twenty- 
 five drops of laudanum contain the soluble portion of one grain 
 of opium. One fluid drachm will, therefore, represent nearly 
 five grains of the solid drug. Lai^danum yields about one 
 hundred and twenty drops to the fluid drachm. Since opium 
 is liable to considerable variation in regard to the proportion of 
 morphine present, and as the strength of the tincture is much 
 influenced by the strength of the spirit used and the period of 
 maceration, and, also, as the tincture itself is sometimes fraudu- 
 lently diluted, it is obvious that laudanum, as found in the shops, 
 is subject to great variation in quality. Poisoning by opium 
 has been of more frequent occurrence than that by any other 
 known substance. 
 
 Symptoms. — When a poisonous dose of opium or of its tinc- 
 ture has been swallowed, the patient is sooner or later seized 
 with confusion in the head, giddiness, and stupor ; the stupor 
 soon increases in intensity, and eventuates in complete insensi- 
 bility. In this state, the respiration becomes slow; the pulse 
 full, slow, and laboring j the eyes closed ; the pupils usually 
 contracted and insensible to light, and the person appears as if 
 in a profound sleep. As the case advances, the countenance 
 becomes pale and ghastly ; the lips livid ; the skin cold and 
 moistened with perspiration ; the breathing slow and stertorous ; 
 the pulse feeble and almost imperceptible ; the limbs relaxed, 
 and death in some instances is preceded by convulsions. Con- 
 vulsions, however, are rarely met with in adults, yet they are 
 not uncommon in children : when they do occur they are often 
 very severe. The pupils, as already stated, are usually con- 
 tracted, being in some cases nearly closed, yet they are not 
 unfrequently dilated, especially in the advanced stage of the 
 case. The state of the pulse is also liable to considerable vari- 
 ation. In some few cases vomiting, and in others purging, has 
 occurred. In fact, a few instances are related in which vomit- 
 ing was about the only symptom produced by large doses of 
 the drug. In cases of recovery from large doses of the poison, 
 the stupor is often foUowed by giddiness, headache, nausea, 
 and vomiting. 
 
PHYSIOLOGICAL EFFECTS. 459 
 
 The time within which the symptoms first manifest them- 
 selves is somewhat various, depending upon a variety of cir- 
 cumstances, but they are not often delayed beyond an hour. 
 In some instances, especially when the poison is taken in a 
 state of solution and on an empty stomach, its effects appear 
 within a few minutes. Dr. Christison (Op. cit., 543) refers to 
 several instances in which the symptoms occurred, in adults, 
 within about ten minutes ; in one of these, the sopor was fairly 
 formed in fifteen minutes after two drachms of solid opium had 
 been taken. In a case quoted by Dr. Taylor (On Poisons, p. 
 588), the patient was totally insensible in fifteen minutes, after 
 the poison had been swallowed. 
 
 On the other hand, a case is reported in which a woman 
 swallowed about eight ounces of solid opium, and in an hour 
 afterwards was able to tell connectedly all she had done (see 
 post). Another instance is related, in which an habitual drunk- 
 ard took, while intoxicated, two ounces of laudanum, and had 
 no material stupor for Jive hours, during which period vomiting 
 could not be induced. Five hours afterwards, he was found 
 insensible, and he eventually died under symptoms of opium 
 poisoning. In a case reported by Dr. Gr. C. Gibb, a healthy 
 man swallowed, with suicidal intent, twelve drachms of lauda- 
 num, and no symptoms of poisoning manifested themselves until 
 nine hours after the dose had been taken ; spontaneous vomiting 
 then occurred, and under careful treatment the patient entirely 
 recovered. (Amer. Jour. Med. Sci., Jan., 1858, p. 288.) In 
 a remarkable instance related by Dr. Christison, a man swal- 
 lowed an ounce and a half of laudanum, and in an hour after- 
 wards, half as much more, and no well-marked symptoms 
 appeared until the eighteenth hour. The patient then became 
 insensible and continued in this condition for several hours ; but 
 he eventually recovered. 
 
 The external application of opium to an ulcerated or abraded 
 surface, and even to the sound skin, has in several instances 
 been followed by serious results. Thus, a child, two months 
 old, nearly perished in consequence of a cerate containing fifteen 
 drops of laudanum having been kept for twenty-four hours on 
 a slight excoriation produced by a fold of the skin. And Sir 
 
460 OPIUM. 
 
 A. Cooper, says he has known a solution of opium applied to 
 an extensive scald on a child, prove fatal. In another case, a 
 young man, suffering under some slight ailment, applied a 
 poultice containing a large quantity of laudanum to the sound 
 skin over the pit of the stomach, after which he went to sleep. 
 Symptoms of narcotism soon appeared, and although the usual 
 treatment was employed, the patient died from the effects of the 
 application. (Stille's Mat. Med., vol. i, p. 671.) 
 
 The administration of opium in the form of enema, has also 
 been followed by fatal results. In a case quoted by Dr. Beck, 
 twelve drops of laudanum, used as an injection to allay the pain 
 consequent on cauterization for a strictured rectum, produced 
 all the symptoms of narcotic poisoning, and death in seventeen 
 hours. (Med. Jur., vol. ii, p. 796.) In a case related by Dr. 
 J. B. Jackson, five drops of laudanum, injected into the rectum 
 of a child eighteen months old, caused death in six hours. 
 (Amer. Jour. Med. Sci., Oct., 1854, p. 384.) In this connection 
 it may be mentioned that. Dr. Christison states that he has 
 given by injection, one fluid drachm and even two drachms of 
 laudanum, without producing any serious symptoms. 
 
 Period when Fatal. — The ordinary duration of fatal poison- 
 ing by opium, according to the observations of Dr. Christison, 
 is from seven to twelve hours. Several instances, however, are 
 recorded in which death took place with much more than the 
 usual rapidity. In a case quoted by Dr. Beck, a soldier, who 
 having taken two ounces and a half of liquor opii sedativus, was 
 rendered totally insensible in fifteen minutes, and died from its 
 effects in one hour and twenty minutes. , (Med. Jur., vol. ii, p. 
 792.) Dr. Gr. Lyman reports a case in which an ounce of lauda- 
 num, taken by a woman, aged fifty-two years, produced violent 
 symptoms in thirty-five minutes, and death in three-quarters of 
 an hour. (Amer. Jour. Med. Sci., Oct., 1854, p. 383.) And, in 
 the Journal just cited, a case is reported by Dr. Coale, in which 
 death took place within the same brief period. These are among 
 the most rapidly fatal cases yet recorded. 
 
 On the other hand, cases are related in which death was 
 delayed much beyond the usual period. Thus, several instances 
 are reported in which death did not take place until from fifteen 
 
FATAL QUANTITY. 461 
 
 to twenty hours after the poison had been taken. In an instance 
 related by Dr. H. F. Campbell, in which nearly three ounces 
 of laudanum had been swallowed, by a young man aged twenty- 
 eight years, death did not ensue until after twenty hours. 
 (Amer. Jour. Med. Sci., Oct., 1860, p. 570.) In a case reported 
 by M. Alibert, death did not occur until the twenty-fourth hour; 
 and in another, mentioned by Dr. Beck, life was prolonged 
 until the forty-eighth hour. The time within which death 
 takes place seems to have but little relation to the quantity of 
 poison taken. 
 
 Fatal Quantity. — The smallest quantity of opium that may 
 destroy life, can not be stated with certainty. Dr. Taylor 
 refers to an instance in which ten grains of the solid drug 
 proved fatal to a man; and another, in which eight grains 
 destroyed the life of a woman. (On Poisons, p. 598.) And 
 Dr. Christison mentions a case in which four grains and a half, 
 mixed with nine grains of camphor, taken by an adult, was 
 followed by the usual symptoms of narcotism, and death in nine 
 hours. In a case reported by Dr. Morland (Amer. Jour. Med. 
 Sci., Oct., 1854), five grains of solid opium, taken in mistake 
 by a gentleman, produced all the usual symptoms of the drug, 
 and the patient barely escaped with his life. 
 
 A case has already been cited in which an ounce of lauda- 
 num proved fatal to an adult in three-quarters of an hour. And 
 in another instance, reported by Dr. W. F. Norris (Amer. Jour. 
 Med. Sci., Oct., 1862, p. 397), a similar quantity caused the 
 death of a healthy man, in about eighteen hours, although the 
 most active remedies were employed. In a case which recently 
 occurred in this city, and for the details of which I am indebted 
 to Dr. R. M. Denig, a robust, healthy girl, aged seventeen years, 
 in a fit of despondency, swallowed two drachms by measure of 
 laudanum. In about three hours afterwards, she was seized 
 with stupor, and died under the usual symptoms of narcotic 
 poisoning in about seven hours after the dose had been taken. 
 The respectable druggist who prepared and sold her the lauda- 
 num, testified that at most it contained the soluble portion of 
 only seven grains of opium. Dr. Toogood relates an instance 
 in which twelve drops of "Battley's sedative" — which is usually 
 
462 OPIUM. 
 
 regarded to have about three times the strength of ordinary 
 laudanum — taken by a feeble woman, aged fifty-five years, pro- 
 duced the usual symptoms of opium poisoning, and death on the 
 following day. (Provincial Med. and Surg. Jour., Nov., 1841, 
 p. 129.) 
 
 Numerous instances are recorded in which extremely small 
 quantities of opium proved fatal to Yerj young children. In a 
 case that fell under our own observation, three drops of lauda- 
 num caused the death of a child two weeks old, in about six 
 hours. In a case mentioned by Dr. Beck, two drops of lauda- 
 num, given four times during a period of eighteen hours, proved 
 fatal to a child six weeks old. Even a single dose of two drops 
 of laudanum caused the death of an infant four days old; and 
 in another instance, an infant six days old was killed by a single 
 drop of the opiate preparation. 
 
 Notwithstanding these facts, recovery has not unfrequently 
 taken place after very large quantities of the drug had been 
 taken. In a case reported by Dr. J. B. Jackson, a woman 
 swallowed ninety grains of solid opium, and was not seen by a 
 physician until three hours after the occurrence. She was then 
 laboring under all the symptoms of opium poisoning; yet under 
 active treatment she eventually recovered. (Amer. Jour. Med. 
 Sci., Oct., 1854, p. 385.) In another case, a stout, muscular 
 woman, who, under disguise, had served several months as a 
 common soldier in the late war, took for the purpose of self- 
 destruction, sixty grains of solid opium ; in about two hours 
 afterwards, being disappointed in the effects of the drug, she 
 swallowed half an ounce of laudanum, and about half an hour 
 later, took as much more. When seen, about three hours and 
 a half after taking the first dose, by Dr. J. B. Thompson, to 
 whom I am indebted for the particulars of the case, she was 
 perfectly rational, and told all she had done. Emetics of sul- 
 phate of zinc and ipecacuanha were then administered, but 
 they did not operate until after about half an hour, when they 
 brought away a large mass of matter having a strong opiate 
 odor; the vomiting was kept up for about three-quarters of an 
 hour. She at no time sufi'ered severe narcotism, was soon out 
 of danger, and rapidly recovered. From several circumstances 
 
ANTIDOTES. 463 
 
 connected with this case, there is no doubt that the patient took 
 the quantities of opium and laudanum stated, which are equal 
 to nearly one hundred grains of the crude drug. 
 
 One of the most remarkable cases of this kind yet recorded, 
 is the following. A pregnant woman, aged thirty-two years, 
 took, with suicidal intent, between seven and eight ounces of 
 solid opium. When seen by a physician in about an hour 
 afterwards, she was able to relate in a connected manner the 
 history of her case. The administration of an emetic caused 
 copious vomiting, by which lumps of opium of the size of 
 hazelnuts were ejected. The emetic was repeated, and its 
 operation encouraged by large draughts of warm water: it was 
 presumed that this vomiting brought away at least three ounces 
 more of opium. The patient then fell into a deep sleep, from 
 which she could with difficulty be roused; but at length she 
 became more sensible, and complained of violent burning pain 
 in the stomach. After a little time, a reaction took place and 
 symptoms of phrenitis manifested themselves, but she finally 
 recovered. (American Medical Recorder, vol. xiii, p. 418.) 
 
 Treatment. — In poisoning by opium or any of its prepara- 
 tions, any portions of the unabsorbed poison should be quickly 
 removed from the stomach. For this purpose, the stomach- 
 pump will usually be found the most efficient ; but in the absence 
 of this instrument, an emetic of from twenty to thirty grains of 
 sulphate of zinc or about ten grains of sulphate of copper, 
 should be exhibited. If neither of these emetics be at hand, 
 powdered mustard or a solution of common salt, should be freely 
 administered. If symptoms of narcotism have already mani- 
 fested themselves, an emetic may fail to act. Under these 
 circumstances, therefore, great caution should be exercised in 
 the administration of any of the more poisonous emetics, such 
 as the sulphate of copper and tartar emetic. 
 
 During the progress of the case, it is of the utmost import- 
 ance that the patient be kept constantly roused. For this pur- 
 pose, various methods have been advised, such as keeping the 
 patient in continual motion, flagellations with wet cloths, and 
 the dashing of cold water over the head and chest. Sometimes 
 the dashing of cold water over the patient insures the operation 
 
464 OPIUM. 
 
 of an emetic. One of the most efficient methods yet proposed 
 for preventing a state of insensibility or for rousing the indi- 
 vidual from this condition, is a current of magneto-electricity 
 applied to the spine and chest. Many cases are reported in 
 which this method was employed with complete success ; and 
 we have in two instances used it with similar results. (Ohio 
 Med. and Surg. Jour., May, 1858, p. 388.) As a stimulant, a 
 strong decoction of coffee has been highly recommended; in 
 fact, several instances are reported in which it is claimed that 
 a decoction of this kind was the means of saving life. In ex- 
 treme cases, artificial respiration has been employed with great 
 advantage. 
 
 As a chemical antidote, Orfila advised the free administra- 
 tion of vegetable solutions containing tannic acid, on the ground 
 that this acid forms with the active principle of opium a com- 
 pound only sparingly soluble in water. So also, solutions of 
 iodine and of bromine, have been strongly recommended. In 
 practice, however, these substances have been found of little 
 service. Various other chemical antidotes have been proposed ; 
 but the utility of these seems to be even more doubtful than 
 that of the substances already mentioned. 
 
 From the apparent antagonistic action existing between the 
 physiological effects of opium and those of belladonna, it has been 
 asserted that these substances are mutually antidotal to each 
 other; and within the last several years, numerous cases have 
 been reported in which it is claimed that treatment based upon 
 this view of their action, was the means of averting death, A 
 recent case of this kind, in which it is believed that three ounces 
 of laudanum had been taken, is related by Dr. H. J. Horton. 
 (Med. and Surg. Eeporter, Philadelphia, Sept., 1866, p. 225.) 
 Out of nine cases of opium poisoning treated by belladonna, 
 and eighteen of belladonna poisoning treated by opium, collected 
 by Dr. W. Norris, of Philadelphia, only two of the former and 
 one of the latter, proved fatal. (Amer. Jour. Med. Sci., Oct., 
 1862, p. 395.) Since, however, recovery has so frequently 
 taken place, even under apparently the most unfavorable cir- 
 cumstances, after enormous doses of opium and of belladonna 
 had been taken, it is impossible to say how far the recovery in 
 
PHYSICAL AND CHEMICAL PROPERTIES. 465 
 
 cases treated after this method, was really due to the alleged 
 antidote. 
 
 Post-mortem Appearances. — The most common morbid ap- 
 pearances after death from poisoning by this substance are, 
 turgescence of the blood-vessels of the brain, eifusion between 
 the membranes and into the ventricles of this organ, a con- 
 gested state of the lungs, and general fluidity of the blood. 
 But these appearances are by no means constant, nor are they 
 peculiar to death from opium. In some few instances, the mu- 
 cous membrane of the stomach has presented a reddened ap- 
 pearance ; but not, perhaps, as the direct result of the action 
 of the poison. When the poison has been taken in its crude 
 state or in the form of laudanum, the contents of the stomach 
 not unfrequently evolve the peculiar odor of opium ; but even 
 this character is often wanting, the poison having disappeared 
 from the stomach prior to death. 
 
 In a case related by Dr. C. A. Lee, in which a large quan- 
 tity of laudanum had been taken and death did not occur until 
 the sixteenth hour, the superficial veins of the scalp were found 
 very fuU of dark uncoagulated blood. The longitudinal and 
 lateral sinuses of the brain were distended with blood ; and be- 
 tween the pia mater and arachnoid membrane, there was a large 
 collection of serum, of a yellowish hue. The choroid plexus 
 was very vascular, and in the bottom of the ventricles there 
 were small flakes of purulent matter. The lungs were con- 
 gested ; and the right side of the heart was fuU of coagulated 
 blood. The mucous villi of the cardiac orifice of the stomach 
 were redder than natural, and much softened. The termination 
 of the oesophagus seemed inflamed, and the mucous lining of 
 the intestines erythematous. (New York Med. and Phys. Jour., 
 No. XXX, p. 297.) 
 
 Physical and Chemical Properties. — Opium, in its solid 
 state, has a reddish-brown color, a well-marked and peculiar 
 odor, and a bitter, acrid taste. The odor of this drug readily 
 serves to distinguish it from aU other substances excepting lac- 
 tucarium, which has a somewhat similar odor. When fresh, 
 opium is quite soft and plastic, but on exposure to the air, it 
 
 30 
 
466 MORPHINE. 
 
 slowly becomes hard and brittle, and is then readily reduced to 
 a yellowish-brown powder. When moderately heated, it melts 
 to a semi-fluid mass, which readily takes fire, burning with a 
 bright flame. It is somewhat heavier than water, its density 
 being about 1"32. Laudanum, or the alcoholic solution of opium, 
 as found in the shops, has a deep brownish-red color, and the 
 odor and taste of the solid drug. The active properties of 
 opium are also taken up by water, when the drug is digested 
 in this liquid ; this extraction is much facilitated by a moderate 
 heat, and also by the presence of a free acid. Chloroform and 
 ether, in their pure state, fail to withdraw the active principles 
 of the drug. 
 
 Since, as already pointed out, opium consists of quite a 
 number of different substances, it is obvious that there can be 
 no single chemical reagent that will show its presence as a 
 whole ; but this may be inferred by proving the presence of one 
 or more of the substances peculiar to it. Although opium con- 
 tains several such substances, the ones usuaUy sought for, in 
 medico-legal investigations, are morphine and meconic acid. 
 Since morphine, as well as several of its salts, is frequently ad- 
 ministered or taken alone, it is obvious that proof of the pres- 
 ence of this alkaloid alone, would not in all cases justify the 
 inference that opium was present. This deficiency, however, 
 is always supplied when the presence of meconic acid has been 
 established. 
 
 Before considering the methods by which morphine and me- 
 conic acid may be separated from complex organic mixtures of 
 the crude drug, the special properties of these substances will 
 be described. The chemical properties of some of the other 
 principles peculiar to opium, will then be considered. 
 
 II. Morphine. 
 
 History and Preparation. — Morphine, as found iu nature, 
 occurs only in opium, in which it exists chiefly in combination 
 with meconic acid, but partly with sulphuric acid. This alka- 
 loid was discovered, in 1804, by Sertiimer; its composition, 
 according to Laurent, is CwHigNOe. 
 
PHYSIOLOGICAL EFFECTS. 467 
 
 Morphine may be obtained, according to the method of 
 Gregory, by treating a concentrated aqueous solution of opium 
 with slight excess of a solution of chloride of calcium. After 
 a little time, especially if warmed, the mixture deposits a copi- 
 ous precipitate, consisting of a mixture of meconate and sul- 
 phate of lime, while chloride of morphine remains in solution. 
 The liquid is then filtered, and the highly colored filtrate con- 
 centrated to the consistency of a thin syrup, when, on cooling, 
 the chloride of morphine separates in its crystalline state, form- 
 ing a nearly solid mass. This is strongly pressed in muslin, 
 redissolved in a small quantity of hot water, the solution filtered, 
 and the salt allowed to recrystallise ; this operation is repeated 
 a second and, if necessary, a third time, using a little prepared 
 animal charcoal to absorb the coloring matter. The salt is now 
 dissolved in hot water, and the solution slightly supersaturated 
 with ammonia, when, on standing, the liberated alkaloid is de- 
 posited in snow-white crystals. 
 
 For the estimation, of the quantity of morphine in opium, 
 M. Eoussille has recently advised the following method. Fifteen 
 parts (15 grammes, or about 225 grains) of opium are treated 
 with twenty-five parts of boiling water till complete disaggrega- 
 tion has taken place ; sixty parts of boiling alcohol are then 
 added, and the mixture digested for an hour. The liquid is 
 then filtered through a linen cloth, and the residue treated with 
 ten parts of water and sixty parts of alcohol, after which it is 
 extracted with fifty parts of boiling absolute alcohol. The 
 united liquids are then allowed to cool, filtered, concentrated to 
 one-third, and again filtered. The morphine is now precipitated 
 by ten parts of ammonia, and the mixture evaporated over sul- 
 phuric acid. At the end of three days, the deposited crystals 
 are collected, washed with ether, then with water, dried, and 
 weighed. (Chemical News, London, Oct., 1866, p. 162.) 
 
 Symptoms. — Considerable difference of opinion has existed 
 as to whether or not the eflfects of morphine and its salts were 
 identical with those occasioned by opium ; but on the whole, 
 the symptoms are much the same, only that the effects of the 
 saline combinations of the alkaloid usually manifest themselves 
 more promptly, than in the case of the crude drug. In addition 
 
468 MORPHINE. 
 
 to the usual narcotic symptoms, itching of the skin, impaired 
 or total loss of vision, and inability to void urine, have fre- 
 quently been observed. Great lividity of the skin has also fre- 
 quently been present. The relative strength of morphine and 
 its salts, is generally estimated to be about five . or six times 
 that of the crude drug. 
 
 In a case reported by Dr. Houston, ten grains of the sul- 
 phate of morphia, given by mistake to a gentleman, aged fifty- 
 nine years, who was laboring under intermittent fever, caused 
 death in less than two hours, although various remedies were 
 employed. Deep stertorous breathing was the only symptom 
 observed. (Beck's Med. Jur., vol. ii, p. 799.) Dr. Christison 
 mentions an instance in which a girl, who had taken ten grains 
 of the chloride, was seized with narcotic symptoms within fif- 
 teen minutes afterwards, and died from its effects in twelve 
 hours. (Op. cit., 558.) And Dr. Taylor cites an instance (On 
 Poisons, p. 617), in which six grains of the same salt, proved 
 fatal to a woman, aged sixty-six years, in nine hours after the 
 poison had been taken. 
 
 In a case quoted by Wharton and Stille (Med. Jur., p. 581), 
 a gentleman afi^ected with acute rheumatism died from the effects 
 of one grain and a third of morphine, taken in four pills at 
 intervals of an hour between each. In another instance, one 
 grain of the chloride, taken in divided doses over a period of 
 six hours, proved fatal to a girl nineteen years old. In a case 
 reported by Dr. Toogood, seven drops of a solution of the ace- 
 tate of morphia (strength not stated), destroyed the life of an 
 aged woman, under the usual narcotic symptoms, in about twelve 
 hours. (Provincial Med. and Surg. Jour., Nov., 1841, p. 129.) 
 In a recent case, a solution containing only the twelfth part of 
 a grain of morphine, administered by mistake, caused the death 
 of an infant. (Chemical News, London, Aug., 1863, p. 98.) 
 
 On the other hand, Mr. Winterbotham reports a case in 
 which a child, two years and three months old, swallowed one 
 grain of the acetate of morphia in solution, and the poison 
 remained undisturbed in the system for two hours and a half. 
 At the end of this period, free vomiting was induced by an 
 emetic of sulphate of zinc ; and under the use of the ordinary 
 
PHYSIOLOGICAL EFFECTS. 469 
 
 remedies, the child entirely recovered. (Amer. Jour. Med. Sci., 
 April, 1863, p. 520.) In a case related by Orfila, a young man 
 entirely recovered within three days, after having taken, with 
 suicidal intent, twenty grains of the chloride of morphine. 
 Within ten minutes after taking the poison, the patient experi- 
 enced a sense of heat in the stomach, with intense itching of 
 the skin ; but over four hours elapsed before symptoms of stu- 
 por manifested themselves. Profound insensibility then super- 
 vened, and he was affected with trismus ; the pupils became 
 slightly dilated ; the surface of the body cold ; the pulse rapid ; 
 the breathing hurried and stertorous ; the abdomen tense and 
 tympanitic, and there were occasional convulsions ; and after- 
 wards he had difficult and scanty micturition, with pain in the 
 kidneys and bladder, and difficulty of swallowing. 
 
 A somewhat similar case, to that just mentioned, is cited by 
 Dr. Christison, in which a young man swallowed fifty grains of 
 the acetate of morphia, and although he was seized within fif- 
 teen minutes with the usual narcotic symptoms of the poison in 
 an aggravated degree, and vomiting could not be induced until 
 four hours afterwards, he finally recovered. One of the most 
 remarkable cases of recovery yet reported, is the following, re- 
 lated by Dr. W. F. Norris. A druggist, aged nineteen years, 
 for the purpose of self-destruction, swallowed seventy-five grains 
 of the sulphate of morphia. No marked symptoms appeared 
 for an hour and a half afterwards, when he began to feel sleepy, 
 and had a staggering gait. Soon after this, emetics were given 
 with the effect of producing free emesis. The patient then be- 
 came unconscious, the pupils contracted to the size of a pin's 
 point, the pulse soft and frequent, and the respiration slow and 
 labored ; but under the active use of remedies, including extract 
 of belladonna, the cold douche and galvanism, he was quite well 
 on the second day after the occurrence. (Amer. Jour. Med. 
 Sci., Oct., 1862, p. 395.) 
 
 The external application of morphine to abraded surfaces, as 
 well as its use in the form of enema, has in several instances 
 been followed by serious, and even fatal results. A quantity of 
 the alkaloid, perhaps about one grain, applied to a blistered 
 surface on the back of the neck of an aged lady, produced, in 
 
470 MORPHINE. 
 
 the course of about two hours, convulsive agitations, cold sweats, 
 extreme prostration, and threatened suflfocation, from which the 
 patient, under active treatment, only slowly recovered. (Amer- 
 ican Medical Intelligencer, vol. ii, p. 13.) In a case quoted by 
 Dr. A. Stille (Mat. Med., vol. i, p. 676), a lady affected with 
 cancer of the uterus was dangerously narcotised by less than 
 one-sixteenth of a grain of chloride of morphine applied to the 
 denuded skin of the epigastrium. 
 
 An enema containing ten grains of sulphate of morphia, 
 prescribed in mistake for quinine, was administered to a child 
 five years old, who was laboring under intermittent fever. 
 Within ten minutes, the child became sleepy, and shortly after- 
 wards it was seized with violent convulsions ; various remedies 
 were now employed, but death speedily ensued. (Med.-Chir. 
 Rev., vol. XV, p. 551.) In another instance, reported by Dr. 
 Anstie, three grains of the alkaloid given inadvertently as an 
 injection caused death in about sixteen hours. (Amer. Jour. 
 Med. Sci., April, 1863, p. 520.) The age of the patient in 
 this case is not stated ; but it would seem that the person was 
 an adult. 
 
 The Treatment and Post-mortem Appearances in poisoning 
 by morphine and its salts, are the same as in poisoning by 
 opium, already described. 
 
 Chemical Properties. 
 
 General Chemical Nature. — Morphine, in its pure state, 
 crystallises in the form of short, colorless, odorless, rectangular 
 prisms, which contain two equivalents of water of crystallisa- 
 tion (C34H19NO6, 2 Aq.). The exact forms of these crystals, 
 however, are subject to considerable variation, depending some- 
 what upon the method employed for their preparation and the 
 strength of the solution from which they were separated, and 
 even upon the quantity of the solution employed. When gently 
 heated, the crystals part with their water of crystallisation and 
 become opake ; at a little higher temperature, they fuse to a 
 brownish liquid, which, if the heat be increased, evolves dense 
 white fumes, then turns black, and is finally consumed. Morphine 
 
SOLUBILITY. 471 
 
 has a very bitter taste, and strong basic properties. It com- 
 pletely neutralises diluted acids forming salts, most of which 
 are crystallisable. It is readily decomposed by concentrated 
 nitric acid, and by hot sulphuric acid; but not by the cold 
 caustic alkalies. 
 
 Solubility. 1. In Water. — When excess of pure, powdered 
 morphine is frequently agitated for twelve hours with water 
 at the ordinary temperature, and the solution then filtered, the 
 filtrate leaves on spontaneous evaporation a crystalline residue 
 indicating that the alkaloid requires about 4,166 times its weight 
 of this menstruum for solution. It is much more freely soluble 
 in hot water. 
 
 2. In Chloroform. — Under the conditions just stated, one 
 part of morphine requires about 6,550 parts by weight of this 
 fluid for solution. 
 
 3. Ether. — Under similar conditions, one part of the alkaloid 
 requires 7,725 parts of absolute ether for solution. Commercial 
 ether of specific gravity 0'733, dissolved one part of the alka- 
 loid in 4,225 parts of the liquid. 
 
 If an aqueous solution of a salt of morphine be decomposed 
 with slight excess of carbonate of soda, and the mixture allowed 
 to repose for a little time so that the liberated alkaloid may de- 
 posit in its crystalline state, and the whole be then agitated 
 with a large quantity of absolute ether, this liquid will take up 
 only a mere trace of the alkaloid, the proportion being even 
 much less than that stated above. If, however, immediately 
 after the addition of the carbonate of soda, the mixture be agi- 
 tated with ether, this fluid will dissolve a mxich larger propor- 
 tion of the alkaloid than above stated : under these conditions, 
 one part of morphine was taken up by 2,500 parts of abso- 
 lute ether. 
 
 4. Alcohol. — When excess of finely-pulverised morphine is 
 digested, with frequent agitation, for ten hours in alcohol of 98 
 per cent., the filtered liquid leaves on spontaneous evaporation, 
 a crystalline residue indicating that one part of the alkaloid had 
 dissolved in 148 parts of the liquid. It is still more freely 
 s oluble in hot alcohol ; but on cooling, the liquid deposits the 
 greater part of the excess, in its crystalline state. A cold. 
 
472 MORPHINE. 
 
 saturated, alcoholic solution of the alkaloid, has a well-marked 
 alkaline reaction. 
 
 5. Alcoholic-ether. — When twenty-five fluid-grains of an 
 aqueous solution containing 10-lOOths of a grain of morphine 
 in the form of acetate, is treated with slight excess of carbonate 
 of soda, and the whole violently agitated with five volumes of a 
 mixture consisting of two parts of absolute ether and one part 
 of pure alcohol, this mixture takes up 9-lOOths of a grain of the 
 liberated alkaloid, which on spontaneous evaporation it leaves in 
 the form of brilliant crystals. When a mixture of this kind is 
 agitated, in the proportions just mentioned, the alcoholic-ether 
 takes up about one-third of the aqueous liquid, the original 
 volume of the latter being reduced to about two-thirds. 
 
 6. Amylic-alcohol. — When excess of the powdered alkaloid 
 is digested in pure amylic-alcohol, with frequent agitation, for 
 four hours at the ordinary temperature, one part is taken up 
 by 133 parts of the menstruum. 
 
 On decomposing twenty-five grain-measures of an aqueous 
 solution containing 10-lOOths of a grain of morphine as acetate, 
 with carbonate of soda, and agitating the mixture with two 
 volumes and a half of amylic-alcohol, this liquid extracted the 
 whole of the alkaloid, excepting the 1 -200th of a grain. 
 
 7. Pure Acetic-ether, when kept in contact with large excess 
 of powdered morphine for several hours, at the ordinary tem- 
 perature and with frequent agitation, dissolves one part in 1,030 
 parts of the liquid. On allowing the solution to evaporate spon- 
 taneously, the alkaloid is left in its crystalline state. In com- 
 mercial acetic-ether, which usually contains alcohol and more 
 or less free acetic acid, the alkaloid is much more freely soluble, 
 even, sometimes, to the extent of one part in 75 parts of the fluid. 
 
 When half a grain of morphine, in the form of sulphate, was 
 dissolved in fifty grains of pure water, the solution rendered 
 slightly alkaline by carbonate of potash, and the mixture thor- 
 oughly agitated with three volumes of pure acetic-ether, in two 
 separate portions, this liquid extracted only the 0'08 of a grain 
 of the liberated alkaloid. 
 
 The alkaloid is readily soluble in solutions of the fixed caus- 
 tic alkalies ; but only sparingly soluble in diluted aqua ammonia. 
 
SPECIAL CHEMICAL PROPERTIES. 473 
 
 The salts of morphine, for the most part, are readily soluble 
 in water, especially if the liquid be slightly acidulated ; they 
 are also soluble in diluted alcohol, but insoluble in chloroform, 
 ether, amylic-alcohol, and pure acetic-ether : they are, there- 
 fore, not extracted from their aqueous solutions by either of the 
 four last-named liquids. Their aqueous solutions, when pure, 
 are colorless, and have the bitter taste of the alkaloid. 
 
 Special Chemical Properties. — If a few crystals of pure 
 morphine be added to a drop or two of concentrated sulphuric 
 acid, they slowly dissolve without change of color, or at most 
 yield a faint pinkish solution. If a crystal of bichromate of 
 potash be now stirred in the solution, it slowly yields green 
 oxide of chromium ; under the same circumstances, a crystal 
 of nitrate of potash produces a dark-brown, muddy mixture. 
 When a little of the alkaloid or any of its salts is dissolved by 
 • the aid of heat in a small quantity of concentrated sulphuric 
 acid, and the solution, after cooling, diluted with a little water, 
 and then a crystal of chromate of potash added, the liquid ac- 
 quires an intensely mahogany-brown color (Otto). Under this 
 treatment, the merest fragment of morphine will yield a very 
 satisfactory coloration. 
 
 Concentrated nitric acid causes the alkaloid to assume a 
 beautiful orange-red color, and dissolves it, with the evolution 
 of binoxide of nitrogen, to a solution of the same hue, which 
 slowly fades to yellow. (See post.) The color of the nitric 
 acid solution, is not affected by chloride of tin. Hydrochloric 
 acid slowly dissolves the alkaloid, without change of color. 
 
 In the following investigations in regard to the reactions of 
 morphine when in solution, pure aqueous solutions of both the 
 sulphate and acetate were employed. The fractions indicate 
 the fractional part of a grain of anhydrous morphine in solution 
 in one grain of the liquid. When not otherwise stated, the 
 results refer to the reaction of one grain of the solution. 
 
 1. Potash and Soda. 
 
 The fixed caustic alkalies, when added in limited quantity, 
 throw down from concentrated neutral solutions of salts of 
 
474 MORPHINE. 
 
 morphine, a white, amorphous precipitate of the anhydrous 
 alkaloid, which in a little time, appropriating two equivalents 
 of water, becomes crystalline. From more dilute solutions, the 
 precipitate does not appear until after some time, and it then 
 separates in its crystalline form. From such solutions, the for- 
 mation of the precipitate is much hastened by stirring the mix- 
 ture with a glass rod. The precipitate is readily soluble in 
 excess of the precipitant, and in free acids, even acetic acid; 
 its nitric acid solution has an orange-red color. 
 
 1. j-oo" grain of morphine, in one grain of water, yields with a 
 
 small drop of the reagent, after a few moments, a crystal- 
 line precipitate, which in a little time, increases to a quite 
 copious deposit, Plate VI, fig. 6. If on the addition of the 
 reagent, the mixture be stirred with a glass rod, it imme- 
 diately yields streaks of crystals along the path of the rod, 
 over the bottom of the watch-glass containing the mixture, 
 and in a few moments, there is a very copious crystalline 
 deposit. Since the precipitate is readily soluble in the 
 fixed caustic alkalies, care should be taken to avoid the 
 addition of much excess of the reagent, otherwise no de- 
 posit will form. 
 
 2. TTo grain, yields after a little time, by stirring the mixture, 
 
 a very good deposit. 
 
 3. 1,000 grain : when the least possible quantity of reagent is 
 
 employed, the mixture yields after a time, a quite satis- 
 factory, granular precipitate. 
 These reagents also produce in solutions of most of the other 
 alkaloids, white, crystalline precipitates ; but the crystalline 
 form of the morphine deposit, when from not too dilute solu- 
 tions, is somewhat peculiar. Its true nature may be fully 
 established by its behavior with nitric acid or some of the 
 other tests mentioned hereafter. 
 
 2. Ammonia. 
 
 Ammonia produces with neutral solutions of salts of mor- 
 phine, much the same results as the fixed alkalies ; but the 
 precipitate is not so readily soluble in excess of the precipitant. 
 
NITRIC ACID TEST. 475 
 
 From dilute solutions, therefore, it is much more easy to obtain 
 precipitates by this reagent than by either potash or soda. If 
 a drop of a solution of the alkaloid be exposed to the vapor of 
 a drop of ammonia, suspended on a glass rod, it yields after a 
 little time, a white, crystalline deposit. This is much the best 
 method for obtaining precipitates from very dilute solutions of 
 the alkaloid. 
 
 The alkaline carbonates, also, throw down from normal solu- 
 tions of salts of morphine a white precipitate of the alkaloid, 
 which is only very sparingly soluble in large excess of the pre- 
 cipitant. If, however, large excess of the reagent be added at 
 first, the formation of the precipitate is partially or entirely pre- 
 vented. The limit of the reaction of these reagents is the same 
 as that of the caustic alkalies. 
 
 3. Nitric Acid. 
 
 When somewhat strong solutions of salts of morphine are 
 treated with large excess of concentrated nitric acid, the mix- 
 ture slowly acquires a lemon-yellow or orange-red color, its 
 exact tint depending upon the relative proportion of acid and 
 morphine present. 
 
 1. y-g-g- grain of morphine, in one grain of water, yields, with a 
 
 few drops of the acid, a yellow solution, which very soon 
 acquires an orange color, then a deep orange-red, after 
 which the liquid slowly becomes again yellow. 
 
 2. 1,000 grain: the mixture slowly acquires a lemon color, which 
 
 after some minutes becomes light orange. 
 
 3. 2,5 grain : after some minutes, the mixture assumes a quite 
 
 perceptible lemon hue, which is best seen over a white 
 ground. 
 The reaction of this test is much more satisfactory and deli- 
 cate when a small portion of the acid is applied to the alkaloid, 
 or any of its salts, in the dry state. 
 
 1. j-g-g- grain of morphine — in the form of sulphate or acetate, 
 as left upon evaporating one grain of its aqueous solution 
 to dryness — when touched with a small drop of nitric acid, 
 almost immediately assumes a fine orange-red color, and 
 
476 MORPHINE. 
 
 dissolves to a solution of the same tint, which slowly fades 
 to yellow. 
 
 2. 1 , J grain : at first the deposit assumes a yellow color, 
 
 which however soon changes to a bright, brownish-orange, 
 and dissolves to a fine orange solution. 
 
 3. s.o'oo grain : the residue assumes a very distinct brown color, 
 
 and dissolves to a faint brownish solution. 
 
 4. 10,000 grain, when touched with a very minute quantity of 
 
 the acid, after a little time acquires a very faint brown- 
 ish hue. 
 Brucine, and strychnine containing this alkaloid, immedi- 
 ately strike a deep blood-red or bright red color when treated 
 with strong nitric acid. This color, however, upon the addition 
 of a solution of protochloride of tin, is changed to bright pur- 
 ple ; whereas, that produced from morphine is unafi^ected, or, at 
 most, is changed to yellow by this reagent. Nitric acid also 
 produces a more or less red coloration with certain volatile oils 
 and resinous substances, but none of these are crystallisable, in 
 which respect they difi^er from morphine. 
 
 4. Iodic Acid. 
 
 When a tolerably strong solution of a salt of morphine, or 
 the alkaloid or any of its salts in the dry state, is treated with 
 a strong solution of iodic acid, the latter is decomposed with the 
 elimination of free iodine, which falls as a brown or reddish- 
 brown precipitate, and the mixture emits the odor of iodine. 
 If a freshly prepared solution of starch-paste be now added, the 
 mixture acquires a blue color, due to the formation of iodide of 
 starch. For the production of this blue color, however, it is 
 necessary, as pointed out by M. Dupre (Chemical News, Dec, 
 1863, p. 267), that the proportions of iodic acid and starch 
 employed, be within certain limits, since the color is destroyed 
 by large excess of iodic acid, and also by large excess of the 
 starch solution. 
 1. y-J-o grain of morphine, in one grain of water, when treated 
 
 in the above manner, yields a blue precipitate and imparts 
 
 a deep blue color to the liquid. 
 
SESQUICHLORIDE OF IRON TEST. 477 
 
 2. T5T grain, yields a brownish liquid, and a quite distinct blue 
 
 precipitate. 
 3- 1.0 grain : the mixture assumes a slight brownish color, 
 but it fails to yield a precipitate. 
 
 This reaction is much more delicate when applied to mor- 
 phine or any of its salts, in the solid state. For this purpose, 
 as advised by M. Dupr^, the morphine or its solution is first 
 treated with a drop of starch solution ; the mixture is then 
 carefully evaporated to dryness, and the residue, after cooling, 
 moistened with a solution of iodic acid. In this manner, a res- 
 idue containing only the 10,000th part of a grain of the alka- 
 loid, will yield a quite distinct blue color. 
 
 The reactions of this test are common to many other sub- 
 stances, some of which, like morphine, are crystallisable. 
 
 M. Lefort has recommended to treat the mixture of mor- 
 phine and iodic acid, with ammonia, instead of starch, by which 
 the yellow color of the mixture is changed to deep brown or 
 yellowish-brown. In applying this method to dilute solutions of 
 the alkaloid, the iodic acid mixture should be allowed to stand 
 some minutes before the ammonia is added, since otherwise the 
 coloration may be entirely prevented. 
 
 This method, when applied to solutions, is much more deli- 
 cate than the starch process before described ; and, moreover, 
 it is said, that the yellow color produced by iodic acid with 
 most other substances capable of reducing this acid, is dis- 
 charged by ammonia, whereby morphine may be distinguished 
 from such substances. For the detection of morphine in highly 
 diluted solutions, the author of this method advises to moisten 
 slips of unsized paper repeatedly with the alkaloidal solution, 
 carefully drying them between each immersion, and then apply 
 the iodic acid solution and ammonia to the paper thus prepared. 
 
 5. SesquicMoride of Iron. 
 
 Concentrated solutions of salts of morphine, as well as the 
 alkaloid or any of its salts in the solid state, strike with a neu- 
 tral solution of sesquichloride of iron or of persulphate of this 
 metal, providing no free acid is present, a deep blue color, 
 
478 MORPHINE. 
 
 which is discharged by free acids, the caustic alkalies, and by 
 heat. On the addition of nitric acid, the blue mixture acquires 
 an orange-red color. 
 !• TS~o grain of morphine, in solution in one grain of water, 
 
 yields with a drop of the reagent, a quite good, ink-blue 
 
 coloration. 
 2. T51T grain : after a few minutes, the reaction is evident, but 
 
 not satisfactory. 
 Sesquichloride of iron also occasions with tannic and gallic 
 acids, a blue color, which is changed to reddish-yellow by nitric 
 acid. When either of these vegetable acids is treated with 
 nitric acid alone, it yields a yellow solution ; in this respect they 
 differ from morphine. There are also some few vegetable infu- 
 sions, which, when treated with a per-salt of iron, give rise to 
 a more or less blue coloration. On the other hand, it should be 
 borne in mind that, the blue color produced by morphine may 
 not make its appearance if the alkaloid be mixed with certain 
 foreign substances. 
 
 6. Iodide of Potassium. 
 
 This reagent produces in somewhat concentrated neutral so- 
 lutions of salts of morphine, especially if the mixture be stirred 
 or allowed to stand some time, a white, crystalline precipitate, 
 which is readily soluble in acids, even acetic acid. This reac- 
 tion is readily interfered with by the presence of foreign sub- 
 stances. 
 
 1. xo"u' grain of morphine, in one grain of water, yields, after 
 
 a little time, a quite copious deposit of large groups of 
 crystalline needles, Plate VII, fig. 1. The precipitate 
 from a solution of the sulphate of morphia, is more prompt 
 in forming, and somewhat more abundant, than that ob- 
 tained from the acetate. 
 
 2. 5-oir grain, yields, after some minutes, a very good, granular 
 
 deposit. 
 This reagent also produces white crystalline precipitates 
 with several of the alkaloids, but the forms of these in most 
 instances differ widely from those obtained from morphine. 
 
CHLORIDE OF GOLD TEST. 479 
 
 7. Chromate of Potash. 
 
 Protochromate of potash throws down from strong neutral 
 sohitions of salts of morphine, a yellow, crystalline precipitate, 
 which is very readily soluble in free acids. 
 
 !• Too" grain of morphine, yields, in a very little time, espe- 
 cially if the mixture be stirred, a very copious, crystalline 
 deposit, having the forms illustrated in Plate VII, fig. 2. 
 2. i .Joo grain, yields after some time, a slight, granular pre- 
 cipitate. 
 Bichromate of potash produces in one drop of a 100th solu- 
 tion of the alkaloid, a yellow, amorphous precipitate, which 
 after a time becomes granular. In solutions but Httle more 
 dilute than this, the reagent fails to produce a precipitate. 
 
 8. Ter chloride of Gold. 
 
 Solutions of salts of morphine, yield with terchloride of gold, 
 a bright-yellow, amorphous precipitate, which almost immedi- 
 ately begins to darken, becoming bluish and finally dirty green 
 or nearly black. Solutions of the sulphate of morphia do not 
 seem to undergo this change as rapidly as those of the acetate. 
 The precipitate is partially soluble in acetic and nitric acids. 
 If the precipitate, as first produced, be treated with a solution 
 of potash, it immediately darkens, and the mixture becomes 
 bluish, purplish or nearly black, its exact color depending upon 
 the relative quantity of reagent employed. 
 !• Tffo" grain of morphine, in one grain of water, yields a very 
 
 copious, yellow deposit, which undergoes the changes above 
 
 described. 
 
 2. 1,0 grain, yields, after a few moments, a very good, yellow 
 
 precipitate, which slowly darkens. When treated with 
 a drop of potash solution, the precipitate dissolves, and 
 the mixture, in a very little time, becomes purplish or 
 nearly black. 
 
 3. 10,0 grain : after a little time, a good precipitate, which 
 
 is readily soluble, to a clear solution, in potash. After 
 
480 MORPHINE. 
 
 some minutes, however, the potash mixture deposits small, 
 black flakes. ' 
 
 4. 2 5 . u grain, yields, after standing some time, a quite dis- 
 tinct turbidity. 
 If the precipitate from ten or fifteen grains of a 1,000th or 
 stronger solution of the allcaloid be boiled in the mixture, the 
 deposit, without dissolving, assumes a brown or dark color, due 
 to its partial decomposition ; the deposit from a 2,500th solu- 
 tion, readily dissolves upon heating, and the mixture on cooling, 
 immediately darkens, from the presence of small, black flakes, 
 which after a time adhere to the sides of the tube ; the precip- 
 itate from a 5,000th solution, readily dissolves by heat, yielding 
 a yellow solution, which imdergoes but little change, even after 
 several hours. 
 
 Besides morphine, tannic and gallic acids and certain other 
 organic substances, have the property of precipitating and re- 
 ducing solutions of salts of gold. With the aid of potash, most 
 organic compounds precipitate the metal in the form of a black 
 powder ; and even a mixture of chloride of gold and potash 
 alone, may after a time, yield black flakes. 
 
 9. Bichloride of Platinum. 
 
 This reagent throws down from concentrated neutral solu- 
 tions of acetate of morphia, a yellow, granular precipitate, 
 which is very readily soluble in acids, even acetic acid. 
 
 One grain of a 100th solution of the alkaloid, yields, espe- 
 ciaUy if the mixture be aUowed to stand some time, a quite 
 good, yellow deposit, Plate VII, fig. 3. Solutions but little more 
 dilute than this, fail to yield a precipitate. 
 
 10. Iodine in Iodide of Potassium. 
 
 A solution of iodine in iodide of potassium produces in solu- 
 tions of salts of morphine, even when highly diluted, a reddish- 
 brown amorphous precipitate, which is but slowly soluble in 
 acetic acid, but dissolves readily, to a clear solution, in caustic 
 potash ; it is also soluble in alcohol. Unless lai'ge excess of the 
 
CARBAZOTIC ACID TEST. 481 
 
 reagent be added, the precipitate after a time partially or en- 
 tirely disappears. 
 
 !• Too" grain of morphine, in one grain of water, yields a very 
 copious deposit. 
 
 2. 1,0 grain: a very good, reddish-brown precipitate. 
 
 3. X 0,0 grain : an immediate turbidity, and in a little time, a 
 
 very fair, brownish-yellow deposit. 
 
 4. 5 0,0 grain, yields a very satisfactory turbidity. 
 Although the reaction of this reagent is common to a large 
 
 class of organic substances, yet it is often useful as a prelimi- 
 nary test ; should it, when applied to a suspected solution, under 
 proper conditions, fail to produce a precipitate, it is quite cer- 
 tain that the other reagents for the alkaloid, would also fail. 
 
 11. Bromine in JBromohydric Acid. 
 
 Neutral solutions of salts of morphine, when treated with a 
 solution of bromohydric acid saturated with bromine, yield a 
 yellow, amorphous precipitate, which after a time dissolves, but 
 is reproduced upon further addition of the reagent. The pre- 
 cipitate is soluble in acetic acid and in alcohol. 
 
 1. -j-g-o grain of morphine, yields a very copious precipitate, 
 
 which remains amorphous. 
 
 2. 1,0*0 grain : a quite good deposit. 
 
 3. 2,50 grain, yields a slight turbidity. 
 
 This reagent also produces similar precipitates with various 
 other organic substances.' 
 
 12. Carhazotic Acid, 
 
 An alcoholic solution of carbazotic acid produces in aqueous 
 solutions of salts of morphine a bright yellow, amorphous pre- 
 cipitate, which is readily soluble in alcohol, but only slowly 
 soluble in acetic acid. The precipitate remains amorphous. 
 
 1. x^ grain of morphine, in one grain of water, yields a very 
 
 copious deposit. 
 
 2. Too' grain, yields a quite distinct precipitate. 
 
 3. 1 00 grain : no indication. 
 
 31 
 
482 MORPHINE. 
 
 This reaction is common to a great number of organic sub- 
 stances, but with several of the other alkaloids, it produces a 
 crystalline precipitate. 
 
 13. Chlorine and Ammonia. 
 
 When a strong solution of a salt of morphine is treated with a 
 stream of chlorine gas, it acquires a deep yellow color, which upon 
 the addition of ammonia, is changed to deep brown. This color 
 is not affected by large excess of ammonia nor by acetic acid. 
 
 1. 100th solution of morphine: ten grains of this solution yield 
 
 results similar to those just described. 
 
 2. 1,000th solution: chlorine imparts to the liquid a yellow tint, 
 
 which is changed to a quite distinct brownish hue by 
 ammonia. 
 Solutions but little more dilute than the last-named, show 
 no change when treated with these reagents. 
 
 Other Beagenis. — lodohydrargyrate of potassium, or a solu- 
 tion of corrosive sublimate containing just sufficient iodide of 
 potassium to redissolve the precipitate first produced, produces 
 in solutions of salts of morphine, even when highly diluted, a 
 white, flocculent precipitate of the double iodide of morphine 
 and mercury, which is only very sparingly soluble in diluted 
 acetic and hydrochloric acids, but readily soluble in large ex- 
 cess of alcohol. The production of a white precipitate by this 
 reagent is common to a large class of organic principles ; in 
 some instances, however, as in the case of strychnine, the pre- 
 cipitate is more or less crystalline. 
 
 Tannic acid throws down from somewhat strong, neutral 
 solutions of salts of the alkaloid a white, flocculent precipitate, 
 which is readily soluble in acids and in the fixed caustic alkalies. 
 Chloride of palladium produces in similar solutions, a yellow, 
 amorphous precipitate, which is also readily soluble in acids. 
 
 When a few drops of a strong solution of a salt of morphine 
 are treated with a strong solution of nitrate of silver, the latter 
 salt, especially if the mixture be gently heated, is sooner or 
 later decomposed, with the production of a shining, crystalline 
 
MECONIC ACID. 483 
 
 precipitate of metallic silver ; at the same time, the mixture 
 acquires a more or less yellow hue, due to the action of the 
 eliminated nitric acid upon the alkaloid. (J. Horsley, Chem. 
 News, July 5, 1862, p. 6.) One grain of a 100th solution of 
 morphine, when treated after this method, yields a very satis- 
 factory deposit. How far this reaction is common to other 
 substances, we are not prepared to say. 
 
 Sulphocyanide of potassium, ferrocyanide and ferricyanide 
 of potassium, acetate of lead, and chloride of barium fail to 
 produce a precipitate, even in concentrated solutions of salts of 
 morphine, at least so far as the alkaloid itself is concerned. 
 
 Among the tests now described for the detection of mor- 
 phine, the reaction of no one of them taken alone, as already 
 intimated, is peculiar to the alkaloid. But by the concurrent 
 action of two or more of them, especially the nitric acid and 
 sesquichloride of iron tests, the true nature of even exceedingly 
 minute quantities of the alkaloid may be fully established, more 
 particularly if it be in its crystalline state. It must be ad- 
 mitted, however, that in regard to delicacy of reaction, the 
 tests at present known for the identification of morphine, are 
 inferior to those for many of the other alkaloids ; and, moreover, 
 as wiU be seen hereafter, this alkaloid is more difficult than most 
 others to separate from foreign organic substances. 
 
 III. Meconic Acid. 
 
 History. — Meconic acid was discovered, in 1804, by Ser- 
 turner. In its pure state, it crystallises in the form of colorless 
 plates, either singly or in groups ; its composition in this form, 
 is 3 HO ; C14HO11, 6 Aq. In nature, it has been found only in 
 the poppy tribe, in which it exists as meconate of morphia. Of 
 good Smyrna opium, it forms about six per cent. ; its propor- 
 tion, however, varies in different samples of the drug, and it is 
 even said to be sometimes altogether absent, but this statement 
 is exceedingly doubtful. 
 
 Preparation. — Various methods have been proposed for the 
 preparation of meconic acid, but we have found the following 
 
484 MECONIC ACID. 
 
 to be one of the most simple, at least if only a small quantity 
 of the substance be desired. A sti-ong, filtered, aqueous solu- 
 tion of opium is treated with excess of acetate of lead, and the 
 impure meconate of lead thus produced collected on a filter and 
 washed, as long as the washings become colored. It is then 
 diffused in a small quantity of water and treated with excess of 
 sulphuretted hydrogen gas, whereby the lead is precipitated as 
 sulphuret, while the liberated meconic acid enters into solution. 
 The liquid is now filtered and evaporated on a water-bath at a 
 very moderate heat, until a drop of it removed to a watch-glass, 
 cooled, and stirred with a drop of hydrochloric acid, yields a 
 crystalline precipitate. The liquid is then allowed to cool, and 
 strongly acidulated with pure hydrochloric acid, when after a 
 time, the meconic acid, being insoluble in diluted hydrochloric 
 acid, will separate in the form of shining plates and crystalline 
 groups. Should the crystals not be entirely colorless, they may 
 be redissolved in a small quantity of hot water, and the cooled 
 solution again strongly acidulated with hydrochloric acid. 
 
 Physiological Effects. — Meconic acid, when taken into the 
 system, seems to be inert. At least, it has repeatedly been 
 administered to inferior animals in doses of several grains, and 
 taken by man in similar quantities, without producing any ap- 
 preciable efi'ect. 
 
 General Chemical Nature. — As usually found in the shops, 
 meconic acid is in the form of crystalline scales, having a more 
 or less reddish color, due to the presence of foreign matter. It 
 has an acid, astringent taste, and strongly acid properties, read- 
 ily uniting with basic oxides, forming salts, called meconates. 
 It, like phosphoric and arsenic acids, is tribasic, or capable of 
 uniting with three equivalents of base. When the crystallised 
 acid is heated, it first parts with its six equivalents of water of 
 crystallisation, then fuses, emits dense white fumes, and finally 
 takes fire, burning with a yellow flame. If the acid be mod- 
 erately heated in a reduction-tube, it sometimes yields a subli- 
 mate of crystalline needles. 
 
 Solubility. — Meconic acid is soluble in about one hundred 
 and fifteen times its weight of pure water, at a temperature of 
 60° F., forming a strongly acid solution. It is much more freely 
 
SPECIAL CHEMICAL PROPERTIES. 485 
 
 soluble in hot water, from which, however, much of the excess 
 separates, in the crystalline form, as the solution cools. In 
 water containing free hydrochloric acid, meconic acid is very 
 much less soluble than in pure water. Alcohol dissolves it 
 rather freely, and leaves it, on spontaneous evaporation of the 
 liquid, in the form of beautiful groups of crystals. It is only 
 very sparingly soluble in absolute ether, requiring about 2,150 
 parts by weight of this liquid for solution ; and it is almost 
 wholly insoluble in chloroform. The salts of this acid, except- 
 ing those of the alkalies, which are freely soluble, are, for the 
 most part, insoluble in water. They are also insoluble, or very 
 nearly so, in alcohol. 
 
 Special Chemical Peopeeties. — Meconic acid, in its solid 
 state, is unchanged in color by cold sulphuric, nitric, and hy- 
 drochloric acids. On the application of a very gentle heat, it 
 dissolves quietly to a clear solution in the first two of these 
 mineral acids, but it is insoluble in hydrochloric acid ; at a little 
 higher temperature, it is readily decomposed, by the mineral 
 acids, with effervescence. When heated to a temperature of 
 about 300° F., solid meconic acid, parting with its water of 
 crystallisation, is resolved into carbonic acid gas and a new, 
 bibasic acid, named comenic, thus : 3 HO ; ChHOu _ 2 HO ; 
 C12H2O8 + 2 CO2. At a somewhat higher temperature, comenic 
 acid in its turn is resolved into carbonic acid gas and pyrome- 
 conic acid, which is monobasic : 2 HO ; C12H2O8 = HO, C10H3O5 + 
 2 CO2. Both these new acids, like the meconic, strike a deep 
 blood-red color with solutions of persalts of iron. The conver- 
 sion of meconic into comenic acid is also effected by boiling an 
 aqueous solution of the acid, the change being much facilitated 
 by the presence of a free mineral acid. When boiled with an 
 aqueous solution of either of the fixed caustic alkalies, meconic 
 acid is resolved into carbonic and oxalic acids and a dark color- 
 ing matter. 
 
 In the following examination of the tests for meconic acid 
 when in solution, pure aqueous solutions of the free acid 
 were employed, it being dissolved when necessary by the aid 
 of a very gentle heat. The fractions indicate the amount of 
 crystallised acid present in one grain of the fluid. Unless, 
 
486 MECONIC ACID. 
 
 otherwise indicated, the results refer to the behavior of one 
 grain of the solution. 
 
 1 . SesquicMoride of Iron. 
 
 Solutions of sesquichloride and of persulphate of iron strike 
 with solutions of meconic acid, as well as with the acid and 
 its salts in the solid state, a deep blood-red color, which is 
 not discharged by either corrosive sublimate or chloride of 
 gold, but readily disappears upon the addition of a solution 
 of protochloride of tin. The red coloration manifests itself 
 in the presence of even large excess of either of the free 
 mineral acids. 
 
 1 . 3-57 grain of meconic acid, in one grain of water, yields with 
 
 a drop of the reagent a deep reddish-brown coloration, 
 which requires several drops of either of the concentrated 
 mineral acids for its discharge, but it is unaffected, further 
 than by dilution, by several drops of a strong solution of 
 either corrosive sublimate or chloride of gold. 
 
 2. TT^oo grain, yields a very good, red coloration. 
 
 3. 10,000 grain : the mixture acquires a very distinct purplish- 
 
 red color. 
 4:- 2 ,0 o~o grain, yields a just perceptible red tint. In several 
 
 drops of this solution, the red coloration is quite distinct. 
 If the meconic acid solution be evaporated by a very gen- 
 tle heat to dryness, and a drop of the reagent applied to the 
 residue : — 
 1 • 10,0 00 grain : the deposit assumes a deep blood-red color. 
 
 2- 5 0.0 -0 grain, yields a very distinct red coloration. 
 
 3- 75.000 grain : the residue acquires a just perceptible red hue. 
 This is the most characteristic test yet known for the iden- 
 tification of very minute quantities of meconic acid, yet it is 
 open to some few fallacies ; but these may be readily guarded 
 against. They are as follows : — 
 
 a. The alkaline sulphocyanides and free hydrosulphocyanic 
 acid yield with persalts of iron a red coloration not to be dis- 
 tinguished, in appearance, from that occasioned by meconic acid. 
 This color, however, unlike that from meconic acid, is quickly 
 
IRON TEST. 487 
 
 discharged by a solution of corrosive sublimate. Tbis latter 
 reagent, therefore, serves to readily distinguish between these 
 substances. It is frequently stated that the red color produced 
 by a sulphocyanide is readily discharged by a solution of chlo- 
 ride of gold, but this is not the case. 
 
 Another method of distinguishing between the red color pro- 
 duced by these diiferent substances, as first proposed by Dr. 
 Percy, is to place in the colored mixture a piece of pure zinc, 
 and then add a drop of sulphuric acid, when in the case of 
 meconic acid, the color is slowly discharged with the evolution 
 of pure hydrogen gas, whereas the color of a sulphocyanide 
 is destroyed with the evolution of sulphuretted hydrogen gas, 
 which may be recognised by its peculiar odor, and by its black- 
 ening a piece of paper moistened with a solution of acetate of 
 lead and suspended over the mixture. This method is not as 
 simple as the preceding ; and, moreover, if the zinc should con- 
 tain sulphur, as is frequently the case, the mixture will evolve 
 sulphuretted hydrogen, even in the absence of a sulphocyanide. 
 
 Human saliva has not unfrequently the property of striking 
 a red color with persalts of iron, due to the presence of a sulpho- 
 cyanide; and Dr. Pereira states (Mat. Med., vol. ii, p. 1,033) 
 that he has on several occasions obtained the same results from 
 the liquid contents of the stomach of subjects in the dissecting- 
 room. However, in the preparation of the contents of this 
 organ for the detection of meconic acid, as pointed out here- 
 after, any sulphocyanide present would be separated with the 
 foreign matter, when this objection would no longer hold. If 
 in any case there is any doubt as to the true nature of the red 
 coloration, this, of course, may be removed by the application 
 of a solution of corrosive sublimate. 
 
 6. Strong solutions of acetic acid and of its neutral salts 
 yield with the iron reagent a more or less red coloration, which, 
 like that from meconic acid, is unaffected by corrosive sublimate 
 and chloride of gold. This color is more readily affected by 
 free mineral acids than that from the opium compound. Solu- 
 tions of acetic acid and of its salts differ from those of me- 
 conic acid, in that they fail to yield a precipitate with acetate 
 of lead. 
 
488 MECONIC ACID. 
 
 c. Persalts of iron also strike with a concentrated decoction 
 of wliite mustard a red color, which, however, is immediately 
 discharged by corrosive sublimate, but not by chloride of gold. 
 
 Besides the substances now mentioned, a strong infusion of 
 Iceland moss, and of some few other rare substances, as first 
 pointed out by Dr. Pereira, will also yield a more ^r less red 
 coloration with the iron reagent ; but these substances are 
 uncrystallisable, and, like those before mentioned, would be 
 removed from the liquid during its preparation for the- appli- 
 cation of the test for meconic acid. The color produced from 
 Iceland moss has a purplish hue, and is unaffected by corrosive 
 sublimate, but it is immediately destroyed by chloride of gold. 
 
 2. Acetate of Lead. 
 
 This reagent throws down from solutions of free meconic 
 acid and of its soluble salts, a yellowish or yellowish-white, 
 amorphous precipitate of meconate of lead (3 PbO ; C14HO1], 
 '2 Aq.), which is insoluble in large excess of acetic acid, but 
 readily soluble, to a clear solution, in diluted nitric acid. If the 
 precipitate be treated with a drop of sesquichloride of iron solu- 
 tion, the mixture acquires a red color. 
 !• ToT grain of meconic acid, in one grain of water, yields a 
 
 very copious, yellowish deposit. 
 2- 1,000 grain : a copious, yellowish-white precipitate. 
 
 3. ro:Vo-o grain, yields a very distinct deposit. 
 
 4. 5-0,000 grain : after a few minutes, a quite distinct opales- 
 
 cence appears, and then, little whitish flakes. 
 
 Acetate of lead also produces precipitates with many other 
 substances, but in these cases the deposit has always, unless 
 foreign matter be present, a pure white color. Among these 
 substances may be mentioned : — 
 
 a. Sulphocyanides, which yield a white precipitate which, 
 like that from meconic acid, is reddened by persalts of iron; 
 but it is readily soluble in acetic acid, and when from strong 
 solutions, insoluble in diluted nitric acid ; when from dilute solu- 
 tions, however, it is readily soluble in the latter acid, to a clear 
 solution. "When treated with metallic zinc and sulphuric acid. 
 
CHLORIDE OF BARIUM TEST. 489 
 
 sulphocyanide of lead undergoes decomposition with the evolu- 
 tion of sulphuretted hydrogen ; whereas, the meconate of lead, 
 as already stated, yields pure hydrogen gas. b. Chlorine yields 
 with the reagent a white precipitate, which when from chloride 
 of sodium is readily soluble in excess of the precipitant, and in 
 acetic and nitric acids; but when due to free chlorine, it is only 
 sparingly soluble in these acids, c. Sulphuric acid, either free 
 or combined, yields a precipitate which is insoluble in acetic 
 acid, and only sparingly soluble in nitric acid. d. Soluble car- 
 bonates occasion a precipitate that is readily soluble with effer- 
 vescence in acetic acid. e. Phosphates and oxalates, also, yield 
 precipitates which are insoluble in acetic acid, but readily sol- 
 uble in nitric acid. So, also, the reagent produces white pre- 
 cipitates with various organic principles ; but these deposits are 
 readily distinguished from the meconic acid compound, in not 
 being reddened by persalts of iron. 
 
 3. Chloride of Barium. 
 
 Strong aqueous solutions of meconic acid and of its alkaline 
 salts, yield with chloride of barium a white crystalline precipi- 
 tate of meconate of baryta, which is insoluble in acetic and 
 diluted nitric acids, and also in caustic ammonia. 
 
 1. Yffo" grain of meconic acid: in a few moments, crystals be- 
 
 gin to appear, and in a very little time, there is a quite 
 copious, crystalline deposit, of the peculiar forms illus- 
 trated in Plate VII, fig. 4. If on the addition of the 
 reagent, the mixture be stirred, it immediately yields a 
 copious crystalline deposit. • 
 
 2. -fiW grain : after a little time, especially if the mixture be 
 
 stirred, there is a quite satisfactory deposit, consisting 
 principally of little masses of aggregated granules. 
 
 3. 1,0 grain: after some time, the mixture yields small, mi- 
 
 croscopic granules. 
 Although this reagent also produces white precipitates in 
 solutions containing sulphuric, phosphoric, and several other 
 acids, yet the crystalline form of the meconic acid deposit is 
 peculiar. 
 
490 MECONIC ACID. 
 
 4. Hydrochloric Acid. 
 
 This acid, in its free state, produces in aqueous solutions of 
 meconic acid and of its soluble salts, when not too dilute, a 
 white precipitate of free meconic acid, due to the insolubility 
 of the latter in the presence of a limited quantity of tl^e re- 
 agent. This precipitate is in the form of transparent crystal- 
 line plates, which, for the most part, are arranged in beautiful 
 groups, and many of which, when examined by transmitted 
 light under the microscope, appear beautifully colored. The 
 formation of the precipitate, is much facilitated by stirring the 
 mixture with a glass rod. 
 
 1. YoT grain of meconic acid, in one grain of water, when 
 
 treated with a drop of concentrated hydrochloric acid : 
 almost immediately crystals begin to form, and in a little 
 time, there is a quite copious deposit, Plate VII, fig. 5. 
 
 2. xoo" grain : after some minutes, providing very large excess 
 
 of hydrochloric acid be not employed, the mixture throws 
 down a very satisfactory, crystalline precipitate. 
 Hydrochloric acid also produces white precipitates in solu- 
 tions containing silver, lead, antimony, and sub-combinations of 
 mercury. But the silver, mercury, and antimony deposits are 
 amorphous, and that from lead, is in the form of crystalline 
 needles ; whereas, the meconic acid precipitate, even from com- 
 plex organic mixtures, is always in the form of crystalline plates. 
 It need hardly be remarked that, the meconic acid precipitate 
 also differs from these fallacious substances in striking a red 
 coior with persalts of iron. 
 
 5. Nitrate of Silver. 
 
 This reagent produces in aqueous solutions of the organic 
 acid' an amorphous precipitate of meconate of silver, which is 
 readily soluble in ammonia and in nitric acid, but insoluble in 
 acetic acid. The color of this precipitate depends somewhat 
 upon the relative quantity of reagent employed : when the lat- 
 ter is in excess, the deposit has a yellow color ; whilst, if there 
 
CHLORIDE OF CALCIUM TEST. 491 
 
 is excess of meconic acid present, the precipitate is white. 
 
 The yellow deposit is said to consist of the tribasic meconate of 
 
 silver (3 AgO ; ChHOu) ; while the white, is a bibasic salt of 
 
 the metal (2 AgO ; C14HO11). 
 
 !• T5T grain of meconic acid, in one grain of water, yields a 
 very copious, pale yellow or yellowish-white, gelatinous 
 precipitate, which after a time acquires a pure yellow 
 color. If several drops of the solution be precipitated by 
 excess of the reagent, the deposit has at once a rather 
 bright yellow hue. 
 
 2. 1,000 grain : a good, flocculent precipitate, having only a 
 
 just perceptible yellow tint. 
 
 3. 10,000 grain : after a time, a quite distinct, flaky deposit. 
 Nitrate of silver also produces yellow or yellowish-white pre- 
 cipitates in solutions containing phosphoric, arsenious, and silicic 
 acids ; but neither of these acids strikes a red color with per- 
 salts of iron. 
 
 6. Ferricyanide of Potassium. 
 
 Strong aqueous solutions of meconic acid and of its alkaline 
 salts, when treated with this reagent, yield, especially if the 
 mixture be stirred and allowed to stand, a crystalline precipi- 
 tate, which is only slowly soluble in acetic acid. 
 
 One grain of a 100th solution of the free acid, yields after 
 a little time, large groups of hair-like crystals, Plate VII, fig. 
 6 ; after about half an hour, the mixture becomes converted 
 into an almost solid crystalline mass. Solutions but little more 
 dilute than this, altogether fail to yield a precipitate. The 
 crystals produced by this reagent are quite characteristic. 
 
 7. Chloride of Calcium. 
 
 This reagent produces in concentrated solutions of the alka- 
 line meconates a white or yellowish-white precipitate of meco- 
 nate of lime. One grain of a 100th solution of the free acid 
 yields no immediate precipitate, but after a little time, large 
 groups of colorless, transparent crystals separate from the 
 
492 MECONIC ACID AND MORPHINE. 
 
 mixture, Plate VIII, fig. 1. The precipitate is insoluble in large 
 excess of acetic acid ; its formation is much facilitated by agi- 
 tating the mixture. 
 
 Other Reagents. — Sulphate of copper throws down from strong 
 aqueous solutions of meconic acid, a greenish-blue, amorphous 
 precipitate of the meconate of copper, which is soluble in acetic 
 acid and in ammonia. Ammonio-sulphate of copper fails to 
 produce a precipitate, even in concentrated solutions of the 
 free acid. 
 
 Saturated aqueous solutions of the free acid faU to yield a 
 precipitate with either of the following reagents : chloride of 
 gold, ferrocyanide of potassium, carbazotic acid, bichloride of 
 platinum, corrosive sublimate, iodine in iodide of potassium, bro- 
 mine in bromohydric acid, tannic acid, and chromate of potash. 
 
 Separation of Meconic Acid and Morphine from Solutions 
 OF Opium and Complex Organic Mixtures. 
 
 The presence of opiimi may be established, as already stated, 
 by showing the presence of meconic acid and morphine. In 
 fact, this may be done by simply proving the presence of me- 
 conic acid ; yet, when possible, it is always advisable to also 
 prove the presence of morphine. Should there be a failure to 
 detect either of these substances, it is pretty certain that there 
 would also be a failure to discover any of the other principles 
 peculiar to the drug. This arises from the fact that the methods 
 at present known for the separation of these latter substances 
 from complex organic mixtures, are much less delicate than 
 those for the recovery at least of meconic acid. In their pure 
 state, however, some of these principles may be identified in 
 even smaller quantity than the organic acid. Before proceed- 
 ing to the preparation of a suspected mixture for the application 
 of chemical tests, it should be carefully examined for the odor 
 of opium; this, however, may not be recognised, even when 
 the drug is present in quite notable quantity. 
 
 Suspected Solutions and Contents of the Stomach. — If 
 the liquid presented for examination appears to be a simple 
 
SEPARATION FROM ORGANIC MIXTURES. 493 
 
 aqueous solution of opium or laudanum, as is sometimes the 
 case, it is slightly acidulated with acetic acid, and evaporated 
 at a low temperature, on a water-bath, to a small volume, then 
 filtered, and the filtrate examined in the manner hereafter di- 
 rected. When, however, the suspected mixture is of a complex 
 nature and contains organic solids, these are cut into very small 
 pieces, the mass, if not already sufficiently liquid, treated with 
 pure water and a little alcohol, and the whole distinctly acidu- 
 lated with acetic acid. It is then very moderately heated, with 
 frequent stirring, for half an hour or longer, allowed to cool, 
 the liquid strained through muslin, and the solid residue on the 
 strainer well washed with strong alcohol and strongly pressed, 
 the washings being collected with the first liquid. The united 
 liquids are now concentrated to a very small volume, on a water- 
 bath at a temperature not exceeding 160° F., and then, after 
 cooling and dilution with water if necessary, filtered through 
 paper previously moistened with water. Any solid matter thus 
 separated, is washed with a little diluted alcohol, and the wash- 
 ings added to the first filtrate. If during the concentration of 
 the liquid, much solid matter separates, it should be removed 
 by a muslin strainer. 
 
 The clear filtrate thus obtained, is J;reated with slight excess 
 of acetate of lead, by which any meconic acid present wiU be 
 precipitated as meconate of lead, together with more or less 
 foreign matter ; at the same time, any morphine and other 
 opium principles present, will remain in solution. Should the 
 liquid contain a sulphocyanide, this will also remain in solution, 
 since, as already pointed out, these salts are not precipitated in 
 the presence of free acetic acid, by the lead reagent. When 
 the precipitate has completely subsided, the mixture is trans- 
 ferred in small portions to a small moistened filter, and the solid 
 residue left on the filter washed with a little pure water, this 
 being collected with the first filtrate. The analysis now divides 
 itself into two branches : — 
 
 1st. Contents of the filter. — While the filter is still moist, its 
 lower end is pierced with a glass rod, and the contents carefully 
 washed, by a jet of water from a wash-bottle, into a tall test- 
 tube, and then allowed to completely subside. After, if thought 
 
494 MECONIC ACID AND MORPHINE. 
 
 best, decanting a portion of the clear supernatant liquid, the 
 precipitate is diffused in the rema;inii)g fluid and treated with a 
 stream of sulphuretted hydrogen gas, as long as a precipitate 
 is produced. By this treatment, any meconate of lead present 
 will be decomposed, the metal being thrown down as black sul- 
 phuret, while the liberated meconic acid will enter into solution. 
 The liquid is then filtered, and the filtrate concentrated at a 
 moderate temperature on a water-bath, when the excess of sul- 
 phuretted hydrogen present will be dissipated. If the liquid 
 contains a quite notable quantity of meconic acid, it will now 
 usually have a more or less reddish or brownish color. 
 
 After the solution thus obtained has cooled, a drop of it is 
 removed to a watch-glass, and tested with a persalt of iron ; 
 if this indicates the presence of meconic acid in quite notable 
 quantity, the remaining liquid is examined by some of the other 
 tests for the organic acid. Should, however, the iron-test fail 
 to yield positive results or indicate the presence of the acid in 
 only minute quantity, the remaining fluid is carefully concen- 
 trated to a very small volume, and consecutive drops examined 
 by sesquichloride of iron, hydrochloric acid, and chloride of 
 barium or ferricyanide of potassium. Should, in any case, the 
 iron-test fail, it is quite certain that the other tests mentioned 
 would also fail, since the former is much the more delicate in 
 its reactions. If the concentrated liquid contains much foreign 
 matter, this may very much interfere with the normal reactions 
 of the tests. Under these circumstances, the liquid may be 
 evaporated at a very gentle temperature to dryness, the residue 
 extracted with a small quantity of strong alcohol, the filtered 
 alcoholic extract evaporated to dryness, and the residue thus 
 obtained dissolved in a very small quantity of warm water and 
 the solution then tested. In some instances, however, it will be 
 found best, for the separation of foreign matter, to reprecipitate 
 the meconic acid by acetate of lead, and then treat the precip- 
 itate in the manner above described. 
 
 By the method now described, the 100th part of a grain of 
 meconic acid in solution in twenty-five grains of water, may be 
 precipitated and recovered, without any appreciable loss. So, 
 also, an alcoholic solution of one grain of opium mixed with 
 
SEPARATION FROM ORGANIC MIXTURES. 495 
 
 foreign organic matter, when treated after this method and the 
 final solution reduced to four drops, gave with the four reagents 
 before named, results somewhat better, in each case, than a 
 100th solution of the pure acid, the last three reagents produc- 
 ing copious crystalline precipitates of the forms peculiar to the 
 organic acid. 
 
 When a solution has been prepared in this manner, the fal- 
 lacies attending the iron-test under certain conditions, do not 
 apply. The manner in which any sulphocyanide present would 
 be avoided has already been indicated ; and as the acetates are 
 aU soluble, they also would remain in solution in the filtrate ; 
 nor could any of the organic infusions that strike a red color 
 with the iron reagent, remain on the filter with the washed 
 meconate of lead. 
 
 Another method frequently advised for decomposing the mec- 
 onate of lead, for the recovery of the organic acid, is to digest 
 it at a moderate heat with diluted sulphuric acid, under the 
 action of which it is resolved into insoluble sulphate of lead and 
 free meconic acid, which enters into solution. Since, however, 
 as already pointed out, meconic acid is prone to undergo decom- 
 position in the presence of a free mineral acid, especially if the 
 mixture be heated to near the boiling temperature, this method 
 may be attended with considerable loss ; moreover, the presence 
 of sulphuric acid would interfere with some of the tests for the 
 organic acid. 
 
 2d. The filtrate. — The above filtrate — which contains the 
 morphine in the form of acetate, and some of the other opium 
 principles, together with any excess of acetate of lead employed 
 in the precipitation of the meconic acid — is treated with excess 
 of sulphuretted hydrogen gas, for the purpose of precipitating 
 the lead. When the precipitate has completely deposited, which 
 may be facilitated by the application of a very gentle heat, the 
 liquid is filtered, and the filtrate evaporated on a water-bath to 
 dryness ; the residue thus obtained is well stirred with a little 
 pure water, and the solution again filtered. A drop of the solu- 
 tion may now be tested for morphine by nitric acid, and another, 
 by sesquichloride of iron. Whether these tests indicate the 
 presence of the alkaloid or not, the remaining liquid, after 
 
496 MECONIC ACID AND MORPHINE. 
 
 dilution if necessary, is rendered slightly alkaline by a strong 
 solution of carbonate of potash, allowed to stand some little 
 time, and then agitated with a few volumes of absolute ether. 
 This liquid will extract some of the opium principles and more 
 or less coloring matter, but leave the liberated morphine in the 
 alkaline aqueous fluid. After carefully decanting the ethereal 
 liquid, and placing it aside for future examination if necessary, 
 the alkaline liquid may be examined by either of the following 
 methods. 
 
 a. The liquid is violently agitated for some minutes, with 
 from four to five times its volume of a mixture consisting of two 
 parts of absolute ether and one part of pure alcohol, by which 
 the alkaloid will be extracted from the aqueous fluid. This 
 operation is best performed by placing the alkaline liquid in a 
 long, graduated tube, and then adding sufficient of the prepared 
 ethereal mixture so that after agitation and repose, the volume 
 of the former liquid is slightly diminished. In certain propor- 
 tions, the liquids will form a homogeneous mixture, while in 
 others, the volume of the aqueous fluid will be augmented, and 
 in others stiU, it will be diminished. If any difficulty is expe- 
 rienced in regard to the separation of the liquids, a little pure 
 ether shoidd be added. 
 
 The alcoholic-ether is now carefully decanted into a large 
 watch-glass, and allowed to evaporate spontaneously, when the 
 morphine will usually be left in its crystalline form ; when, 
 however, there is only a minute quantity of the alkaloid present 
 or it is mixed with much foreign matter, it may remain in its 
 amorphous state. When the residue has become quite dry, it 
 is carefully washed, by gently rotating a few drops of pure 
 water over it in the glass and then decanting the liquid. Small 
 portions of the residue are now separately examined by nitric 
 acid and a persalt of iron, and any remaining portion dissolved, 
 by the aid of a trace of acetic acid, in a very small quantity 
 of water, and the solution then submitted to some of the liquid 
 tests for morphine. By exposing a portion of the aqueous so- 
 lution to the vapor of ammonia until it acquires a very slightly 
 alkaline reaction, and then exposing it to the air, for sev- 
 eral hours if necessary, the alkaloid will be deposited in its 
 
SEPARATION FROM ORGANIC MIXTURES. 497 
 
 crystalline form, even when present in only very minute quan- 
 tity. In this manner, we have on several occasions obtained 
 very satisfactory crystals, when every other method failed to 
 reveal the alkaloid in this form. 
 
 On applying the method now described, for the extraction 
 of morphine, to a complex organic mixture containing only one 
 grain of opium, the meconic acid having been previously pre- 
 cipitated from the aqueous solution by acetate of lead, the 
 alcoholic-ether left on spontaneous evaporation, a very fine crys- 
 talline deposit of the alkaloid. 
 
 i. Another method for the extraction of the morphine, is to 
 agitate the alkaline liquid, as first suggested by Uslar and Erd- 
 mann (See ante, p. 417), with two or three times its volume of 
 hot amylic-alcohol, in which, as already shown, the alkaloid is 
 rather freely soluble. When the fluids have completely sep- 
 arated, the upper, or alcoholic, liquid is transferred, by means 
 of a caoutchouc-pipette, to a watch-glass ; the aqueous fluid is 
 then washed with a fresh portion of the hot alcohol, and this 
 transferred to the watch-glass containing the liquid first em- 
 ployed. In the absence of a caotitchouc-pipette, the alkaline 
 liquid may be removed from the alcoholic, by closing the upper 
 end of an ordinary pipette with the finger and passing the open 
 end to the bottom of the fluid mixture, when upon removing 
 the finger, the aqueous liquid will be forced into the tube, and 
 may thus be removed. The employment of the ordinary suc- 
 tion-pipette, on account of the injurious action of the alcohol 
 on the respiratory organs, is inadmissible. 
 
 The amylic-alcohol is now evaporated, at a very gentle heat 
 on a water-bath, to dryness, when the alkaloid may be left in 
 its crystalline form ; but it is much less apt to be left in this 
 form, under these circumstances, than when separated by spon- 
 taneous evaporation from the above ethereal mixture. Should- 
 the residue be amorphous, it may be re-dissolved in a small 
 quantity of diluted, ordinary alcohol, and the liquid allowed to 
 evaporate spontaneously. The residue is then examined in the 
 ordinary manner. 
 
 In the application of this method for the recovery of minute 
 quantities of morphine from complex mixtures containing known 
 
498 MECONIC ACID AND MORPHINE. 
 
 quantities of opium, we have obtained very satisfactory results ; 
 and on the whole, perhaps, this process is preferable to the 
 ether method before described. 
 
 c. A third method that may be employed for the extraction 
 of the alkaloid, from the foregoing alkaline solution, is by means 
 of acetic-ether, as recently advised by M. Alfred Valser. (Chem. 
 News, 1864, vol. ix, p. 289; from Jour. Pharm. et Chimie, 
 xliii, 49, 63.) The operation may be conducted in much the 
 same manner as when amylic-alcohol is employed, and the liquid 
 allowed to evaporate spontaneously. If this method be adopted, 
 it should be borne in mind that morphine is much less soluble 
 in pure acetic-ether than in either amylic-alcohol or a mixture 
 of alcohol and ether ; and, therefore, that a correspondingly 
 larger proportion of this liquid wiU be required for the extrac- 
 tion of a given quantity of the alkaloid. On the' other hand, 
 this liquid, when pure, has a much less solvent action upon 
 foreign organic matter than either of the other liquids named, 
 particularly a mixture of alcohol and ether ; at the same time, 
 it is more likely than amylic-alcohol, on evaporation, to leave 
 the alkaloid in the crystalline form. It may here be remarked, 
 that acetic-ether, as found in the shops, not unfrequently con- 
 tains so much alcohol as to cause it to mix in all proportions 
 with water, when agitated with this liquid. 
 
 The absolute ether with which the alkaline solution was 
 washed, previous to the extraction of the morphine, contains 
 narcotine and some other opium principles, together with more 
 or less foreign organic matter. When evaporated spontaneously, 
 it usually leaves, if there is not much foreign matter present, a 
 transparent amorphous residue, which when treated with a drop 
 of concentrated sulphuric acid, dissolves to a blood-red solu- 
 tion ; if a small crystal of nitrate of potash be stirred in this 
 mixture, the color of the latter is changed to brownish or 
 purplish. These results, however, being due to the combined 
 action of several diiferent substances, are subject to consider- 
 able variation. 
 
 Porphyroxin. — For the detection of small quantities of opium, 
 Merck advises to take advantage of the property possessed by 
 porphyroxin, one of the constituents of the drug, of being 
 
SEPARATION FROM ORGANIC MIXTURES. 499 
 
 reddened when heated with hydrochloric acid. For this pur- 
 pose, the opium solution is rendered alkaline by caustic potash 
 and agitated with pure ether, in which this principle is soluble. 
 A strip of white bibulous paper is then repeatedly dipped into 
 the decanted ethereal liquid, the paper being dried between 
 ■ each immersion ; the paper is now moistened with hydrochloric 
 acid, and exposed to the vapor of boiling water, when it will 
 acquire, especially after drying, a more or less rose-red color. 
 On following these directions, for the examination of solutions 
 containing very notable quantities of opium, we failed to obtain 
 very satisfactory results ; with larger quantities of the drug, 
 however, the red coloration was well marked. 
 
 According to Merck, porphyroxin, in its pure state, may be 
 obtained by the following process. Powdered opium is ex- 
 hausted by boiling ether, then made into a pulp with water, 
 slight excess of carbonate of potash added, the mixture agitated 
 with ether, the ethereal liquid evaporated to dryn^ess, the resi- 
 due thus obtained dissolved in a small quantity of very dilute 
 hydrochloric acid, and the solution rendered slightly alkaline by 
 ammonia, by which the porphyroxin, together with paramor- 
 phine, will be precipitated. On dissolving the precipitate in 
 ether, and allowing the liquid to evaporate spontaneously, the 
 former of these principles is left in the form of a resin, while 
 the latter is deposited in the crystalline form. They may now 
 be separated by cautiously treating the mixture with alcohol, 
 in which the porphyroxin is soluble ; the alcoholic solution is 
 then evaporated to dryness at a low temperature. .Porphyroxin 
 is described as a neutral substance, which crystallises in brill- 
 iant needles, is readily soluble in alcohol and in ether, but insol- 
 uble in water. It is biit proper to add, that the existence of 
 this substance, as a distinct opium principle, has been doubted 
 by several experimentalists. 
 
 Examination for Morphine alone. — When there is reason to 
 suspect that morphine, or one or other of its salts, is present in 
 its free state, the same method of analysis may be followed as 
 for its recovery from organic solutions containing opium, ex- 
 cepting that the use of acetate of lead is omitted. Thus, the 
 mixture, slightly acidulated with acetic acid, is digested at a 
 
500 MECONIC ACID AND MORPHINE. 
 
 moderate temperature with diluted alcohol, allowed to cool, the 
 liquid strained, then concentrated on a water-bath to a small 
 volume, filtered, and the filtrate evaporated to dryness. The 
 residue, thus obtained, is treated with a small quantity of water, 
 the solution filtered, the filtrate rendered slightly alkaline with 
 carbonate of soda, washed with absolute ether, and the alka-- 
 loid, if present, extracted by either of the methods heretofore 
 described. 
 
 It rarely happens, under these circumstances, that the ana- 
 lyst is able to determine the acid with which the morphine was 
 combined. Should, however, the mixture be not too complex, 
 it may be concentrated on a water-bath to a very small volume, 
 then gently warmed with a little concentrated alcohol, and the 
 filtered liquid allowed to evaporate spontaneously, when the 
 morphine salt may be deposited in its crystalline state. A por- 
 tion of any deposit of the salt thus obtained, is dissolved in a 
 small quantity of pure water, and the nature of the acid de- 
 termined by appropriate tests. 
 
 Feom the Tissues. — Thus far, with very few exceptions, 
 there seems to have been an entire failure to recover the poison 
 from the tissues, in poisoning by opium, and its active alkaloid. 
 And in the examination of the liver of two different animals 
 poisoned by the drug, we met with similar results. If it be 
 desired to examine the tissues for the absorbed poison, the solid 
 organ, as a portion of the liver, cut into very small pieces and 
 triturated in a mortar, is made into a thin paste with water con- 
 taining a little alcohol, then acidulated with acetic or sulphuric 
 acid, and the whole digested, with frequent stirring, at a mod- 
 erate heat for about an hour. When the mass has cooled, the 
 liquid is strained through muslin, and the solids upon the 
 strainer well washed with diluted alcohol, and strongly pressed. 
 The mixed liquids may then be examined after the manner 
 already described. 
 
 Feom the Blood. — Among various methods pursued for the 
 recovery of minute quantities of meconic acid and morphine, 
 when purposely added to healthy blood, the following gave the 
 best results. The fluid, acidulated with acetic acid in the 
 proportion of about eight drops of the concentrated acid for 
 
RECOVERY FROM THE BLOOD. 501 
 
 each fluid ounce of blood, is thoroughly agitated, best in a tol- 
 erably wide-mouthed bottle, with an equal volume of strong 
 alcohol, and the mixture gently heated in a porcelain dish on a 
 water-bath, until the albuminous matter has collected into little 
 flakes. The cooled mass is thrown on a wet linen strainer, 
 and the solids well washed -with alcohol, and strongly pressed. 
 These are again thoroughly mixed with fresh alcohol, gently 
 warmed, and the liquid strained as before. The united strained 
 liquids are now concentrated on a water-bath to a small volume, 
 again strained, and then filtered. If during the concentration 
 of the liquid, much solid matter separates, as is usually the 
 case, it is removed by a strainer. 
 
 The filtered liquid thus obtained, is evaporated to dryness 
 on a water-bath, the residue digested with a small quantity of 
 nearly absolute alcohol, the solution filtered, and the filtrate 
 evaporated to dryness. This residue is gently warmed with a 
 small quantity of water,, and the Hquid filtered. On now treat- 
 ing the filtrate with acetate of lead, any meconic acid present 
 wiU be precipitated as meconate of lead : it should be borne in 
 mind that under these circumstances, the lead reagent not un- 
 frequently produces a yellowish- white precipitate, even in the 
 absence of meconic acid. Any precipitate thus obtained, is 
 separated by a filter and examined in the usual manner for the 
 organic acid, while the filtrate is tested for morphine. 
 
 The repeated digestions with alcohol, in the above process, 
 are rendered necessary on account of the extreme tenacity with 
 which these opium principles, especially the meconic acid, ad- 
 here to the albuminous matter of the blood. In fact, this organic 
 acid forms with albumen a precipitate, which is almost insoluble 
 in water, and only slowly yields the acid to alcohol. 
 
 In operating on a fluid ounce of blood, according to this 
 method, the smallest quantities of meconic acid and morphine 
 from which we succeeded in recovering crystals of both sub- 
 stances, were the twentieth part of a grain of each. In one of 
 these instances, the final morphine solution being concentrated 
 to three drops, two of the drops gave respectively with nitric 
 acid and sesquichloride of iron, very satisfactory evidence of 
 the presence of the alkaloid, while the third, when exposed to 
 
502 MECONIC ACID AND MORPHINE. 
 
 the vapor of ammonia, and then to the air for several hours, 
 deposited four comparatively large groups of crystals of the 
 pure alkaloid. In the same case, the evidence of the presence 
 of the meconic acid, was about equally satisfactory. 
 
 With mixtures containing smaller quantities of the opium 
 principles, the final solutions, even when only the 100th part of 
 a grain of each substance had been added, gave results that no 
 doubt were due to the presence of these principles ; yet the 
 reactions were by no means conclusive. On examining for only 
 one of these substances, crystals may be obtained from a some- 
 what smaller quantity of either th^n before stated. 
 
 On applying the foregoing method to the examination of the 
 blood of eight different dogs and cats poisoned by opium, the 
 final solutions in some instances gave results, which there is 
 little doubt were due to the presence of meconic acid and mor- 
 phine; while in others, they failed to reveal the presence of a 
 trace of either of these substances. In no instance, however, 
 were crystals obtained or were the results, with perhaps a 
 single exception, such as would have been satisfactory in an 
 unknown case. 
 
 In the exception just mentioned, two grains of morphine in 
 solution, had been given to a large cat ; an hour afterwards, an 
 ounce of laudanum was administered, and in another hour, an 
 ounce more. In an hour after the last dose, the animal was 
 killed by a blow on the head, and four ounces of blood were care- 
 fully taken from the body. On treating the whole of the fluid 
 after the manner before shown, and concentrating the final solu- 
 tion supposed to contain meconic acid, to two drops, and testing 
 one of these directly with sesquichloride of iron, and evaporat- 
 ing the other to dryness and testing the residue in the same 
 manner, both gave results identical with those occasioned by 
 minute traces of the organic acid. So, also, the morphine solu- 
 tion, when reduced to two drops and these tested separately by 
 nitric acid and a persalt of iron, gave equally distinct evidence 
 of the presence of the alkaloid. 
 
 Bearing in mind, that at most only a minute quantity of the 
 organic poisons enter the blood, the great loss attending the 
 separation of the opium principles from this fluid, and the want 
 
FAILURE TO DETECT. 503 
 
 of delicacy and precision of the tests under these circumstances, 
 we were not much disappointed in the results of the foregoing 
 experiments. 
 
 The Urine. — According to M. Boucharda*, morphine when 
 taken either in its free state or under the form of opium, speed- 
 ily appears in the urine ; and may be detected by the liquid 
 yielding a reddish-brown precipitate with a solution of iodine 
 in iodide of potassium. Since, however, as we have already 
 seen, this reagent also produces similar precipitates with most 
 of the other alkaloids and with certain other organic substances, 
 this reaction in itself could by no means be regarded as direct 
 proof of the presence of this alkaloid. Moreover, we find that 
 the reagent not unfrequently throws down a precipitate from 
 what may be regarded as normal urine ; while on the other 
 hand, it sometimes fails to produce a precipitate, even when 
 comparatively large quantities of the alkaloid have been pur- 
 posely added to this liquid. 
 
 Failure to detect the Poison. — It has not unfrequently 
 happened, that there was a failure to detect a trace of either 
 meconic acid or of morphine in any part of the alimentary canal, 
 even when large quantities of the poison had been taken, and 
 the conditions for its detection were apparently very favorable. 
 Thus, in a case related by Dr. Christison, he failed to obtain 
 any direct evidence of the presence of the poison in the con- 
 tents of the stomach of a young woman who died in five hours 
 after taking not less than two ounces of laudanum. In another 
 case, the contents of the stomach evacuated two hours after 
 seven drachms of laudanum were swallowed, had no odor of 
 opium, nor did they reveal the presence even of meconic acid. 
 Since the tests and methods for separating meconic acid from 
 foreign substances are somewhat more satisfactory than those 
 for morphine, the acid has sometimes been detected when there 
 was a failure to detect the alkaloid. 
 
 On the other hand, the poison has been detected, even when 
 taken in comparatively only small quantity and death was de- 
 layed for several hours. In a case related by Dr. Skae, in 
 which not more than half an ounce of laudanum had beeft taken, 
 and death did not occur until thirteen hours afterwards, the 
 
504 NARCOTINE. 
 
 contents of the stomach furnished evident indications of the 
 presence of morphine, and faint evidence of meconic acid. It 
 need hardly be remarked, that since opium or its active alka- 
 loid is so frequently administered medicinally, the detection of 
 mere traces of the poison in the dead body would not in itself 
 be positive proof that it was the cause of death. 
 
 Quantitative Analysis. — For the purpose of estimating the 
 quantity of morphine present in an aqueous solution of any of 
 its salts, the somewhat concentrated solution may be slightly 
 supersaturated with pure aqua ammonia, and allowed to stand 
 quietly in a cool place for about twenty-four hours. The alka- 
 loid, with the exception of the merest trace, will now be pre- 
 cipitated in its crystalline form. The crystals are then care- 
 fully separated from the liquid, washed with absolute ether, 
 dried at the ordinary temperature, and weighed. One hundred 
 parts by weight of the pure crystallised alkaloid represent 123"8 
 parts of crystallised chloride of morphine, Ca^HigNOs, HCl, 6 
 Aq.; 125 parts of the crystallised sulphate, CgiHigNOe, HO, SO3, 
 5 Aq. ; or 113'8 of the acetate of morphia, C34H19NO6, HO, 
 C4H3O3. 
 
 The quantity of opium or morphine found in the stomach, 
 in poisoning by one or other of these substances, is usually too 
 minute to admit of a direct quantitative analysis. Under these 
 circumstances, the quantity may sometimes be estimated with 
 considerable accuracy by observing the intensities of the reac- 
 tions of the reagents applied, and comparing these with the 
 reactions of known quantities of the poison. 
 
 IV. Naecotine. 
 
 History. — The existence of narcotine was first pointed out, 
 in 1803, by Derosne, but Robiquet, in 1817, was the first to 
 indicate its chemical nature. Blyth, in 1844, assigned to it the 
 formula C46H25NO14. The more recent investigations of Messrs. 
 Matthiessen and Foster, led them to adopt the formula C44H23 
 N0i4- iJour. Chem. Soc, 1863, p. 342.) Wertheim has de- 
 scribed three homologous forms of narcotine in opium, having 
 
CHEMICAL PROPERTIES. 505 
 
 the fornnilse C44H23NO14, C^jHasNOH, and CigHayNOH; which he 
 named, respectively, methylo-, ethylo-, and propylo-narcotine, 
 from the fact that when passed over soda-lime, they yield meth- 
 ylamine, ethylamine and propylamine. The investigations of 
 Matthiessen and Foster, as well as those of Dr. Anderson, how- 
 ever, render the existence of these varieties very doubtful. 
 
 Narcotine usually constitutes from six to eight per cent, of 
 good Smyrna opium ; but in some varieties of the drug, it forms 
 only about one per cent. As this substance may be extracted 
 from the drug by ether, without the addition of either an alkali 
 or an acid, it would appear that it exists principally in its free 
 state. It has only feebly basic properties. 
 
 Preparation. — This substance may be obtained, either by 
 adding ammonia to the mother-liquor from which chloride of 
 morphine has been prepared, or by digesting the insoluble part 
 of opium in acetic acid, and precipitating by ammonia. The 
 impure narcotine is purified by digesting its hot alcoholic solu- 
 tion with animal charcoal, and recrystallising (Gregory). 
 
 Physiological Effects. — Much discrepancy has existed among 
 experimentalists in regard to the action of narcotine upon the 
 animal system, some observers considering it as almost inert, 
 whilst others attribute to it narcotic properties. These narcotic 
 eifects, however, may have been due to the presence of mor- 
 phine in the preparation employed. Recently, Dr. O'Shaugh- 
 nessy, of Calcutta, has attributed to it powerful antiperiodic 
 properties, and has used it, he states, with great success in the 
 treatment of intermittent fever. He prescribed it in doses of 
 three grains, three times a day. 
 
 Chemical Peopeeties. — In its pure state, narcotine crys- 
 tallises in the form of transparent, colorless, rhombic prisms, 
 which contain one equivalent of water, Ci^HjjNO,!, Aq. ; some- 
 times, however, it appears in the form of oblong plates, and at 
 others, as a granular powder. In its solid state, it is nearly 
 destitute of taste, but when in solution, it has an intensely bit- 
 ter taste, even exceeding that of morphine. When moderately 
 heated, it parts with its water of crystallisation and fuses to a 
 colorless liquid ; at higher temperatures, it takes fire, burning 
 with a smoky flame. Under the action of oxidising agents. 
 
506 NARCOTINE. 
 
 narcotine is readily decomposed, giving rise to a variety of new 
 compounds, among which is opianyl, one of the other opium 
 principles. The pure alkaloid, when in solution, has little or 
 no action upon reddened litmus-paper, in which respect it dif- 
 fers from morphine ; so, also, unlike morphine, it fails to strike 
 a blue color either with a persalt of iron, or a mixture of iodic 
 acid and starch. 
 
 Narcotine fails to neutralise diluted acids, but it readily 
 unites with them, forming salts, which, for the most part, are 
 uncrystallisable. Concentrated sulphuric acid slowly dissolves 
 the alkaloid to a yellow solution, which when stirred with a 
 crystal of nitrate of potash, acquires a deep blood-red color. 
 When the simple acid solution is moderately heated, it acquires 
 a purplish color, even when only a very minute quantity of the 
 alkaloid is present. When the acid solution is stirred with a 
 crystal of bichromate of potash, the results depend much upon 
 the relative quantity of the salt employed (see post). Concen- 
 trated nitric acid also dissolves the alkaloid to a more or less 
 yellow solution ; hydrochloric acid dissolves it without change 
 of color. It is slowly soluble in large excess of concentrated 
 acetic acid, but insoluble in the diluted acid. 
 
 When large excess of powdered narcotine is digested for 
 twenty-four hours, at the ordinary temperature, with pure water, 
 this liquid fails to dissolve even the 20,000th part of its weight 
 of the alkaloid. Absolute ether, under similar circumstances, 
 takes up one part of the alkaloid in 208 parts of the liquid. 
 Narcotine is soluble in all proportions in chloroform, and dis- 
 solves readily in alcohol, but is insoluble in the caustic alkalies. 
 The salts of the alkaloid, are, for the most part, readily soluble 
 in water and in alcohol. 
 
 Narcotine and morphine may be separated from each other 
 by agitating the mixture with chloroform or ether, which will 
 dissolve the former but not the latter; so, also, these substances 
 may be separated by a solution of either of the fixed caustic 
 alkalies or by diluted acetic acid, which will take up the mor- 
 phine but not the narcotine. 
 
 Narcotine may be readily separated from aqueous solutions 
 of its salts by treating the solution with slight excess of a free 
 
BEHAVIOR WITH THE ALKALIES. 507 
 
 alkali, and agitating the mixture with chloroform or ether. 
 Upon spontaneous evaporation, the extracting liquid will usu- 
 ally leave the alkaloid in the form of beautiful groups: of brill- 
 iant crystals, similar to those of the crystallised acetate (Plate 
 VIII, fig. 3). 
 
 In the following examination of the reactions of narcotine 
 when in solution, the pure alkaloid was dissolved in water by 
 the aid of the least possible quantity of hydrochloric acid. The 
 fractions employed, indicate the amount of pure alkaloid in so- 
 lution in one grain of water ; and, \mless otherwise intimated, 
 the results refer to the behavior of one grain of the solution. 
 
 1. The Alhalies and their Carbonates. 
 
 Caustic potash, soda, and ammonia, as well as their carbon- 
 ates, produce in aqueous solutions of salts of narcotine a white 
 precipitate of the free alkaloid, which is insoluble in even large 
 excess of the precipitant and in diluted acetic acid, but readily 
 soluble in hydrochloric and nitric acids. After a little time, 
 the precipitate becomes crystalline. 
 !• TooT grain of narcotine, in one grain of water, yields a very 
 
 copious, amorphous deposit, and very soon, the mixture 
 
 becomes a nearly solid crystalline mass. 
 
 2. 1,000 grain, yields an immediate precipitate, which in a little 
 
 time becomes converted into beautiful, and somewhat char- 
 acteristic, crystalline tufts, Plate VIII, fig. 2. 
 
 3. 10,000 grain : an immediate cloudiness, and in a few mo- 
 
 ments crystals appear ; after a little time, there is a quite 
 good crystalline precipitate, the crystals having the forms 
 just illustrated. 
 
 4. 4 0,000 grain : if only a very minute trace of the reagent be 
 
 employed, the mixture soon becomes opalescent, and after 
 a little time, especially when examined by the microscope, 
 yields a very satisfactory deposit of crystalline needles. 
 This precipitate fails to appear in the presence of even 
 very slight excess of the reagent. 
 If a drop of an aqueous solution of a salt of narcotine be 
 exposed to the vapor of ammonia, it soon becomes covered with 
 
508 NARCOTINE. 
 
 a white crystalline film, even when it contains only the 5,000th 
 part of its weight of the alkaloid. 
 
 2. Sulphuric Acid and Nitrate of Potash. 
 
 If a solution of narcotine or of any of its salts be evaporated 
 to dryness, the residue dissolved in a small quantity of concen- 
 trated sulphuric acid, and then a small crystal of nitrate of 
 potash or a trace of free nitric acid be stirred in the mixture, 
 the latter quickly acquires a deep blood-red color, even if only 
 a minute quantity of the alkaloid be present. This color is 
 discharged by large excess of free nitric acid. 
 !• TW grain of narcotine, when dissolved in a single drop of 
 the concentrated acid, and a small crystal of nitre added, 
 yields a deep red coloration. If the nitre be first dis- 
 solved in the acid and the mixture 'then allowed to flow 
 over the narcotine deposit, the latter immediately assumes 
 a deep red color, and slowly dissolves to a solution of the 
 same hue. 
 2. ] , u grain : if the acid mixture be flowed over the deposit, 
 the latter becomes blood-red, and soon dissolves to a yel- 
 low solution. 
 3.' 10,000 grain: the deposit acquires a red color, and very 
 soon dissolves to a faintly yellow solution. 
 This is one of the most characteristic tests yet known for 
 the detection of narcotine. Under its action, the true nature of 
 the precipitate produced by the caustic alkalies or their carbon- 
 ates, may be fully established. For this purpose, the precipi- 
 tate is Washed, dried, then dissolved in a drop of sulphuric acid, 
 and a small crystal of nitre stirred in the solution. 
 
 When a solution of narcotine in concentrated sulphuric acid 
 is stirred with a very small crystal of bichromate of potash, the 
 fluid acquires a beautiful wine color, which remains unchanged 
 for many days. If, however, an excess of the potash salt be 
 used, the liquid passes through several colors, and ultimately 
 becomes either green or blue, the final color depending upon 
 the relative amount of salt employed. The permanent color is 
 readily obtained by stirring the potash salt in the acid solution 
 
ACETATE OF POTASH TEST. 509 
 
 until it imparts the desired tint, and then removing the crystal 
 from the mixture. The color may thus be obtained from even 
 a very minute quantity of the alkaloid. 
 
 3. Acetate of Potash. 
 
 A solution of acetate of potash produces in aqueous solutions 
 of salts of narcotine a white precipitate of the acetate of narcot- 
 ine, which is insoluble in large excess of the precipitant, but 
 readily soluble in most free acids, and in excess of the narcot- 
 ine solution. If, therefore, the solution contain a free acid, or 
 if excess of the reagent be not added, the mixture may fail to 
 yield a precipitate. The formation of the precipitate from dilute 
 solutions, is much facilitated by stirring the mixture. 
 
 1. jw grain of narcotine, in one grain of water, yields a very 
 
 copious, amorphous deposit, which after a time, becomes 
 converted into beautiful groups of crystals, Plate VIII, 
 fig. 3. _ 
 
 2. TTooTi grain : an immediate cloudiness, and soon, a quite good 
 
 crystalline deposit. 
 
 3. s7o"iro grain, yields, after a little time, a good deposit of crys- 
 
 talline needles. 
 
 4. ro^Vo'o grain : after a few minutes, crystals appear. 
 
 5. 2 0,000 grain : after several minutes, crystalline needles ap- 
 
 pear along the edge of the drop, and after a time, there 
 is a very satisfactory deposit. 
 
 The same precipitate is thrown down from solutions of salts 
 of narcotine by other acetates, such as the acetate of baryta, 
 zinc, and of lead ; but the reactions of these, especially the last 
 mentioned, are not quite so delicate as that of the potash salt. 
 
 The production of a precipitate by the neutral alkaline ace- 
 tates is rather characteristic of narcotine, since it is the only 
 substance, except solutions of salts of silver and suboxide of 
 mercury, with which they produce a precipitate, at least in the 
 form of an acetate. In solutions containing silver or mercury, 
 however, the reagent fails to produce a precipitate unless the 
 solution be quite concentrated and a corresponding solution of 
 the reagent be employed. 
 
510 NARCOTINE. 
 
 As the acetates thus serve for the detection of narcotine, so 
 on the other hand, solutions of salts of the alkaloid, serve for 
 the precipitation of combined acetic acid, for which heretofore we 
 had no ready precipitant. However, as the acetate of narcot- 
 ine is readily soluble in excess of a soluble salt of the alkaloid, 
 the latter is not so delicate a test for the acetates as these are 
 for narcotine. 
 
 4. Chromate of Potash. 
 
 Protochromate of potash throws down from aqueous solutions 
 of salts of narcotine a yellow amorphous precipitate, which after 
 a time becomes crystalline. The precipitate is readily soluble 
 in acids, even acetic acid. 
 
 !• ToTT grain of narcotine, in one grain of water, yields a very 
 copious deposit, which slowly assumes the crystalline form. 
 
 2. i,Joo grain: a quite good precipitate, which soon yields crys- 
 
 talline tufts of the same form as produced by the caustic 
 alkalies (Plate VIII, fig. 2). 
 
 3. 5,0 grain : much the same as 2. The formation of the 
 
 crystals is much facilitated by stirring the mixture. 
 
 4. 1 . u grain, yields in a very little time, especiaUy by stir- 
 
 ring, a good crystalline deposit. 
 
 5. 2 5,000 grain : after a few minutes, a very satisfactory de- 
 
 posit of crystalline needles and tufts. 
 
 The forms of the crystals produced by this reagent are 
 somewhat peculiar to- solutions of narcotine. 
 
 Bichromate of potash produces in somewhat strong solutions 
 of salts of the alkaloid a 'yellow amorphous precipitate, which 
 after a time becomes granular. One grain of a 100th solution of 
 the alkaloid yields a copious deposit ; and a similar quantity of 
 a 500th solution, a quite fair, light yellow precipitate ; but a 
 1,000th solution fails to yield any visible change. 
 
 5. Sulphocyanide of Potassium. 
 
 This reagent occasions in solutions of salts of narcotine a 
 white precipitate, which is insoluble in the alkalies, but readily 
 soluble in acids, even acetic acid. 
 
IODINE TEST. 511 
 
 1. Yffo" grain of narcotine, yields a very copious deposit, which 
 
 soon becomes a mass of crystals of the same form as those 
 produced by the caustic alkalies. 
 
 2. 1,0^0 grain : an immediate precipitate, which soon becomes 
 
 crystalline. 
 
 3. 10,0 grain : after a little time, especially if the mixture be 
 
 stirred with a glass rod, it yields a very satisfactory crys- 
 talline deposit. 
 
 4. 2 5.000 grain : after a time, a quite satisfactory deposit of 
 
 crystalline needles. 
 This reagent produces no precipitate in solutions of salts of 
 morphine. 
 
 6. Ter chloride of Gold. 
 
 Terchloride of gold produces in solutions of salts of narcot- 
 ine a bright yellow, amorphous precipitate, the color of which 
 is permanent, even upon the addition of caustic potash : in this 
 respect narcotine differs from morphine. Upon heating the 
 mixture, the precipitate dissolves, but it is reproduced as the 
 solution cools. The precipitate is but very sparingly soluble in 
 large excess of acetic acid. 
 
 1. -j-g-o grain of narcotine, in one grain of water, yields a very 
 
 copious precipitate. 
 
 2. 1,0^0 grain: a very good deposit, which is insoluble in sev- 
 
 eral drops of a strong solution of caustic potash. 
 
 3. 10,0 grain, yields a very satisfactory. precipitate. 
 
 4:. 2 0.^0 grain : after a little time, a quite perceptible de- 
 posit. 
 
 5. 4 0^0 grain, yields a perceptible turbidity. 
 
 7. Iodine in Iodide of Potassium. 
 
 A solution of iodine in iodide of potassium throws down 
 from solutions of salts of narcotine a reddish-brown, amorphous 
 precipitate, which is nearly insoluble in the caustic alkalies, and 
 only very sparingly soluble in acetic acid. 
 
 1. YoT grain of narcotine, yields a very copious deposit. 
 
 2. 1 J grain : a copious precipitate. 
 
512 NARCOTINE. 
 
 3. X 0.0 grain, yields a quite good precipitate, which is readily , 
 
 soluble to a clear solution in caustic potash. 
 
 4. 50,00 0' grain : a brownish-yellow deposit. 
 
 5. 10 0% grain, yields a very perceptible turbidity. 
 
 8. Bromine in JBromohydric Acid. 
 
 A solution of bromohydric acid saturated with bromine, 
 produces in solutions of salts of narcotine a bright yellow, amor- 
 phous precipitate, which is insoluble in large excess of the pre- 
 cipitant, and only sparingly soluble in acetic acid. Upon the 
 addition of caustic potash, the precipitate acquires a white 
 color, except when produced from very dilute solutions, when 
 it dissolves to a clear liquid. 
 
 1. Yoo grain of narcotine, yields a very copious precipitate, 
 
 which after a time dissolves, but it is reproduced upon 
 further addition of the reagent. 
 
 2. iT^oiJ grain : a copious precipitate, which is soluble in caus- 
 
 tic potash, but is almost immediately replaced by a white 
 deposit. 
 
 3. 10,0 grain : a quite good deposit, which when dissolved in 
 
 potash, yields a slight, Avhite precipitate. 
 
 4. 5 0.0 grain, yields a quite distinct, yellowish precipitate. 
 
 5. 1 0% grain : a quite distinct cloudiness. 
 
 9. Ferrocyanide of Potassium. 
 
 This reagent produces in aqueous solutions of salts of nar- 
 cotine a dirty-white, amorphous precipitate, which is very read- 
 ily soluble in acetic acid, bixt insoluble in large excess of the 
 precipitant. 
 
 1. y^ grain of narcotine, in one grain of water, yields a quite 
 
 copious deposit. 
 
 2. i,Joo grain : a very good precipitate. 
 
 3. 10,0 grain, yields a quite strong turbidity. 
 Ferricyanide of potassium throws down from quite strong 
 
 solutions of narcotine a yellow, amorphous precipitate, which is 
 readily soluble in excess of the precipitant,' and in acetic acid. 
 
CODEINE. 513 
 
 10. Carbasotic Acid. 
 
 An alcoholic solution of carbazotic acid throws down from 
 solutions of salts of narcotine a bright yellow, amorphous pre- 
 cipitate, which is slowly soluble in large excess of the precip- 
 itant, and also in large excess of acetic acid. 
 !• TW grain of narcotine, yields a very copious precipitate, 
 which remains amorphous. 
 
 2. 1,000 grain : a very good deposit. 
 
 3. 10.0 grain, yields a quite obvious precipitate. 
 
 Sichloride of Platinum produces in somewhat strong solu- 
 tions of salts of narcotine, a light-yellow amorphous precipitate, 
 which is sparingly soluble in acetic acid. One grain of a 100th 
 solution of the alkaloid, yields a very copious precipitate, and 
 the same quantity of a 1,000th solution, a quite fair deposit; 
 but a 2,500th solution yields no indication. Chloride of palla- 
 dium produces similar results. Tannic acid and corrosive subli- 
 mate throw down from concentrated solutions of the alkaloid, 
 white amorphous precipitates. 
 
 When somewhat strong solutions of salts of narcotine are 
 treated with a stream of chlorine gas, the liquid quickly assumes 
 a yellow color, which soon changes to reddish-brown ; on now 
 adding a solution of ammonia, the mixture acquires a deep 
 brown color. Ten grains of a 100th solution of the alkaloid, 
 will yield these results. A similar quantity of a 1,000th solution, 
 when treated with the gas, acquires a distinct yellow tint, which 
 is changed to reddish-brown by ammonia. In these reactions, 
 narcotine closely resembles morphine. 
 
 V. Codeine. 
 
 History. — Codeine, or codeia, as it is frequently called, was 
 first discovered, in 1832, by M. Eobiquet. It exists in opium 
 in combination with meconic acid, and usually forms consider- 
 ably less than one per cent, of the crude drug. The formula 
 for codeine, in its anhydrous state, according to Gerhardt, is 
 
 33 
 
514 CODEINE. 
 
 CjjHaiNOe; in its crystalline form, it usually contains two equiv- 
 alents of water of crystallisation. It has a bitter taste, and 
 strong alkaline properties, quickly restoring the blue color of 
 reddened litmus-paper. 
 
 Preparation. — Codeine may be obtained, according to Dr. 
 Gregory, by concentrating the mother-liquor from which mor- 
 phine has been precipitated, when, after a time, a mixture of 
 the chlorides of codeine and morphine, will be deposited. This 
 deposit is dissolved in a little hot water, and the solution treated 
 with excess of potash, which precipitates the codeine, partly in 
 the form of crystals, and partly as a viscid mass, which soon 
 becomes solid and crystalline ; at the same time, most of the 
 morphine present remains in solution in the alkaline liquid. 
 The precipitate is then treated with ether or with water, either 
 of which will dissolve the codeine, while any morphine present 
 will remain undissolved. The ethereal solution, upon spontane- 
 ous evaporation, leaves the alkaloid in the form of beautiful an- 
 hydrous prisms ; while the aqueous solution deposits it in the 
 form of octahedral crystals, containing two equivalents of water 
 of crystallisation. 
 
 Physiological Effects. — The statements in regard to the effects 
 of codeine, when taken into the stomach, have been quite con- 
 tradictory. According to the results of some observers, it has 
 strong narcotic properties, similar to "those of morphine, only 
 that it has to be given in larger quantity, and never induces 
 the unpleasant after-effects so frequently witnessed in the ad- 
 ministration of that alkaloid. Dr. Gregory observed that in 
 some instances it excited a sense of intense itching of the entire 
 skin, and states that probably the itching caused in some per- 
 sons by opium and some of the salts of morphine may be due 
 to the action of codeine, this substance being not unfrequently 
 present in some of the preparations of morphine. On the other 
 hand, other observers were led to conclude that codeine was 
 nearly or entirely destitute of narcotic properties. Dr. Wood 
 is of the opinion, that it is among the principles upon which 
 opium depends for its peculiar properties. 
 
 Chemical Properties. — Codeine is a white, crystallisable, 
 and strongly basic substance, precipitating the oxides of many 
 
CHEMICAL PROPERTIES. 515 
 
 of the metals from solutions of their salts, but in its turn being 
 precipitated by the caustic alkalies. It is readily distinguished 
 from morphine by not striking a blue color with a persalt of 
 iron. When heated, it first parts with its water of crystallisa- 
 tion, and at about 300° F., fuses to a colorless liquid, which at 
 higher temperatures takes fire, burning with the evolution of 
 dense fumes. 
 
 Codeine completely neutralises diluted acids, combining with 
 them to form salts, most 'of which are readily crystallisable. 
 Concentrated sulphuric acid slowly dissolves the pure alkaloid 
 without change of color ; if a solution of this kind be heated 
 on a water-bath, it acquires a beautiful purple color, even when 
 only a minute quantity of the alkaloid is present : this result, 
 however, is somewhat influenced by the amount of acid and 
 heat employed. A small crystal of nitrate of potash stirred in 
 the cold acid solution, yields a faint greenish, then reddish col- 
 oration ; while a crystal of bichromate of potash, yields a green 
 color, due to the formation of sesquioxide of chromium. Con- 
 centrated nitric acid, it is said, produces no change of color 
 with codeine ; but the few samples we have examined became 
 more or less orange-yellow, and dissolved to a yellow solution, 
 when treated with this acid, especially when a not inconsider- 
 able quantity of the alkaloid was employed. Similar results 
 have also been obtained by various other observers. Chloride 
 of tin added to the nitric acid solution, causes it to undergo 
 little or no change. Hydrochloric acid readily dissolves the 
 alkaloid to a colorless solution, which remains unchanged upon 
 the application of heat. 
 
 When excess of finely-powdered codeine is digested with 
 pure water at the ordinary temperature, with frequent agitation, 
 for twenty-four hours, the solution then filtered, and the filtrate 
 evaporated to dryness, it leaves a crystalline residue indicating 
 that one part of the alkaloid had dissolved in 128 parts of the 
 fluid. It is much more freely soluble in hot water, from which, 
 however, much of the excess separates as the solution- cools. 
 Absolute ether, under the foregoing conditions, dissolves one 
 part of the alkaloid in 55 parts of the liquid. Chloroform, un- 
 der similar conditions, takes up one part in 21 -5 parts of fluid. 
 
516 CODEINE. 
 
 The alkaloid is also freely soluble in alcohol, and somewhat sol- 
 uble in solutions of the caustic alkalies, but less so than in pure 
 water. The salts of codeine are, for the most part, readily- 
 soluble in water, and in alcohol; but they are nearly or alto- 
 gether insoluble in ether, and in chloroform. 
 
 Aqueous solutions of codeine, when not too dilute, have a 
 strongly alkaline reaction and a very bitter taste. The alkaloid 
 may be extracted from its aqueous solution by agitation with 
 ether ; but as codeine is not very "much less soluble in water 
 than in ether, repeated agitations with the latter are required 
 for the complete separation of the alkaloid. It is much more 
 readily extracted by chloroform. By either of these liquids, it 
 may be separated from morphine. The alkaloid may, of course, 
 be extracted in a similar manner from aqueous solutions of its 
 salts, by first treating them with slight excess of a free min- 
 eral alkali. 
 
 The codeine employed in the following investigations, was 
 prepared by E. Merck, of Darmstadt ; it was in the form of 
 large, colorless crystals, and apparently perfectly pure. Its so- 
 lutions were prepared in the form of the acetate. The fractions 
 indicate the fractional part of a grain of the pure alkaloid in 
 solution in one grain of water ; and, unless otherwise stated, 
 the results refer to the behavior of one grain of the solution. 
 
 1. Potash and Ammonia. 
 
 The fixed caustic alkalies and ammonia throw down from 
 concentrated aqueous solutions of salts of codeine a white amor- 
 phous precipitate of the pure alkaloid, which is readily soluble 
 in free acids. 
 
 One grain of a 100th solution of the alkaloid, yields a quite 
 good deposit, which remains amorphous. On account of the 
 solubility of codeine in water, solutions but little more dilute 
 than that just mentioned fail to yield a precipitate with either 
 of these reagents. 
 
 Since the alkaloid is less soluble in alkaline solutions than 
 in pure water, it is partly precipitated from its pure aqueous 
 solutions, when not too dilute, by the caustic alkalies. 
 
IODINE AND BROMINE TESTS. 517 
 
 2. Iodine in Iodide of Potassium. 
 
 A solution of iodine in iodide of potassium produces in solu- 
 tions of salts of codeine a reddish-brown precipitate, which is 
 readily soluble to a colorless solution in caustic potash ; it is 
 also soluble in acetic acid. 
 
 !• T5~o grain of codeine, in one grain of water, yields a very 
 copious precipitate, which after a time becomes more 
 or less crystalline, Plate VIII, fig. 4. The precipitate 
 is readily soluble in alcohol, from which after a time it 
 separates in the form of crystalline plates, Plate VIII, 
 fig. 5, which are especially beautiful under polarised hght. 
 Solutions but little more dilute than this, fail to yield 
 crystals. 
 
 2. 1,0 grain, yields a copious deposit. 
 
 3. 10.0 grain: a very good, reddish-yellow precipitate. 
 
 4. 5 0.0 grain : a yellowish deposit. . 
 
 5. 10 0% grain : a quite perceptible precipitate. 
 
 6. 5 0^00 grain, yields a distinct turbidity. 
 
 This reagent also produces crystalline precipitates with some 
 of the other opium principles ; but the deposits produced by the 
 reagent from most other substances remain amorphous. 
 
 3. Bromine in Bromohydric Acid. 
 
 A solution of bromohydric acid saturated with bromine throws 
 down from solutions of salts of codeine a yellow amorphous pre- 
 cipitate, which after a time dissolves, but it is reproduced upon 
 further addition of the reagent. 
 
 !• Too grain of codeine, yields a very copious, bright-yellow 
 deposit. 
 
 2. T,wo grain: a copious precipitate. 
 
 3. 10.0 grain: a fair, yellow deposit. 
 
 4. 2 5,0 grain, yields a quite perceptible cloudiness. 
 
 The reaction of this reagent is common to solutions of most 
 of the alkaloids, and also to other organic principles. 
 
518 CODEINE. 
 
 4. Sulphocyanide of Potassium. 
 
 This reagent occasions in somewhat strong solutions of salts 
 of codeine a white crystalline precipitate of the sulphocyanide 
 of codeine, which, according to Anderson, has the composition 
 GgeHjzNOe, C2NS2, Aq. The precipitate is readily soluble in 
 acetic acid. 
 
 1. Yho grain of codeine: after some minutes, crystalline needles 
 begin to separate, and after a little time, there is a copious 
 crystalline deposit, Plate VIII, fig. 6. If the mixture be 
 stirred, it immediately yields crystals, and very soon the 
 drop becomes a mass of crystalline groups. 
 2- Too grain: by stirring the mixture, crystals soon appear, 
 and after a time, there is a very satisfactory deposit. 
 This reagent also produces crystalline precipitates with solu- 
 tions of several of the other alkaloids. 
 
 5. Bichromate of Potash. 
 
 Bichromate of potash produces in quite strong solutions of 
 salts of codeine a yellow crystalline precipitate, which is readily 
 soluble in acetic acid. Very concentrated solutions of the alka- 
 loid yield beautiful groups of bold, red crystals. 
 
 One grain of a 100th solution yields no immediate precipi- 
 tate, but after standing some time, crystalline tufts separate, 
 and the mixture ultimately becomes a nearly solid mass of crys- 
 tals, Plate IX, fig. 1. The formation of the precipitate is much 
 facilitated by stirring the mixture. 
 
 Protochromate of potash produces with very strong solutions 
 of the alkaloid, a yellow precipitate of crystalline plates and 
 prisms. 
 
 6. Chloride of Gold. 
 
 Terchloride of gold throws down from solutions of salts of 
 codeine a reddish-brown amorphous precipitate, which when 
 treated with caustic potash yields a dark bluish mixture. 
 !• TW grain of codeine, yields a very copious precipitate : after 
 
CARBAZOTIC AND NITRIC ACID TESTS. 519 
 
 standing some time, the supernatant fluid acquires a blu- 
 ish color. 
 
 2. 1,00 grain, yields a very good, yellow deposit. 
 
 3. 5,000 grain, yields a very distinct cloudiness. 
 
 7. Bichloride of Platinum. 
 
 This reagent precipitates from strong solutions of salts of 
 codeine a yellow amorphous deposit, which is readily soluble in 
 acetic acid, but unchanged by caustic potash. 
 
 1. ^-gTj- grain of codeine, yields a copious deposit, which after a 
 
 time becomes more or less granular. 
 -■ sTo grain, yields after several minutes, a partly granular 
 precipitate. 
 
 8. Carhazotic Acid. 
 
 An alcoholic solution of carbazotic acid produces in solu- 
 tions of salts of codeine, a bright yellow, amorphous precipitate. 
 !• TWO grain of codeine, yields a very copious deposit. 
 
 2. 1,0^0 grain: a quite good precipitate. 
 
 3. 2.500 grain, yields, after a little time, a quite distinct 
 
 cloudiness. 
 
 9. Nitric Acid and Potash. 
 
 When a small quantity of codeine, in its solid state, is added 
 to a drop of concentrated nitric acid, it dissolves with the evo- 
 lution of hyponitric acid, yielding an orange-yellow solution, 
 which when evaporated to dryness on a water-bath, leaves a 
 yellow residue. If this residue be treated with a drop of caus- 
 tic potash, it acquires a beautiful orange color, and partially 
 dissolves to a solution of the same hue, which is permanent. 
 
 1. YoT grain of codeine, yields the results just described. 
 
 2. i,Joo grain : the nitric acid solution leaves a slightly yellow 
 
 residue, which with potash yields a good orange-colored 
 mixture. 
 
 3. 10,0 grain : the slightly yellow residue left by the acid, is 
 
 but little changed by the potash ; but if this mixture be 
 
520 NARCEINE. 
 
 evaporated, it leaves a yellowish-orange deposit, mixed 
 with crystals of the nitrate of potash : a drop of water 
 readily dissolves these crystals, and yields a yellow-orange 
 mixture, the color of which is permanent. 
 
 'Iodide of Potassium produces in concentrated solutions of 
 salts of codeine, especially upon stirring the mixture, a crystal- 
 line precipitate of tufts of needles, Plate IX, fig. 2. 
 
 Corrosive sublimate, ferro-, and ferri-cyanide of potassium, 
 sulphate of copper, and nitrate of silver produce no precipitate, 
 at least immediately, in a 100th solution of salts of codeine. 
 
 VI. Naeceine. 
 
 History. — Narceine, which is said to form from six to twelve 
 per cent, of Smyrna opium, was discovered, in 1832, by Pelle- 
 tier. Its formula, according to Dr. Anderson, is C^HagNOig. It 
 seems to be a neutral substance, yet it will unite with acids to 
 form salts, all of which have an acid reaction. The statements 
 of observers in regard to the constitution and properties of nar- 
 ceine have been very conflicting, and it is probable that two or 
 perhaps three different substances have been described under 
 this name. 
 
 Preparation. — This substance may be obtained, according to 
 Dr. Anderson (Quart. Jour. Chem. Soc, vol. v, p. 257), from 
 the mother-liquor of chloride of morphine by diluting it with 
 water, filtering, and then adding ammonia as long as a precip- 
 itate is produced. Narceine and meconin remain in solution, 
 while narcotine, resin, and small quantities of papaverine and 
 thebaine are deposited. The filtered liquid is treated with ex- 
 cess of acetate of lead, the dirty-brown precipitate produced 
 removed by a filter, the excess of lead separated from the fil- 
 trate by sulphuric acid, and the liquid saturated with ammonia, 
 then evaporated at a moderate temperature to a syrup, when it 
 is allowed to stand some days. The precipitate then formed, is 
 collected on a cloth and washed with water, then boiled with a 
 large quantity of water and the hot solution filtered. On cool- 
 ing, the liquid becomes filled with fine silky crystals of narceine, 
 
CHEMICAL PROPERTIES. 521 
 
 which are separated from traces of sulphate of lime by solution 
 in alcohol, and further purified by boiling with animal charcoal 
 and recrystallisation from water. 
 
 Physiological Effects. — Experiments upon inferior animals 
 indicate narceine to be an inert substance. 
 
 Chemical Properties. — Narceine crystallises in beautiful, 
 colorless, delicate needles, which when dry form an exceedingly 
 light, spongy mass. It is unchanged by persalts of iron. At 
 a moderate heat it fuses to a clear liquid, and at higher temper- 
 atures burns like a resin. 
 
 The narceine used in the present investigations was pre- 
 pared by E. Merck ; it was in the form of very delicate, color- 
 less) silky needles. 
 
 Concentrated sulphuric acid causes the alkaloid to assume a 
 reddish-brown color, and dissolves it to a reddish or yellowish- 
 red solution, which upon the application of a moderate heat ac- 
 quires an intense red color, and at higher temperatures darkens. 
 These results, however, are much influenced by the amount of 
 acid and heat employed. In no instance, with the single speci- 
 men examined, did we obtain the green color described by 
 Anderson (Quart. Jour. Chem. Soc, vol. v, p. 259), nor, with 
 the diluted acid, the blue color obtained by other observers. 
 A crystal of nitrate of potash stirred in the cold acid solution, 
 yields a reddish-brown, violet or purple coloration, according to 
 the relative quantities of the different substances present : the 
 color is discharged by heat. Bichromate of potash produces 
 with the acid solution, a dirty-red color, which on the applica- 
 tion of heat is changed to green, due to the production of ses- 
 quioxide of chromium. 
 
 When treated with concentrated nitric acid, narceine assumes 
 an orange-red color and dissolves to a more or less yellow solu- 
 tion, which suffers little or no change by a moderate heat. The 
 solution is unaffected by chloride of tin, even upon the applica- 
 tion of heat. The sample under consideration, when dropped into 
 concentrated hydrochloric acid, became blue, and dissolved to a 
 perfectly colorless solution. Pelletier described this reaction as 
 characteristic of narceine, while Anderson failed to obtain a blue 
 color from samples which he considered pure. 
 
522 NARCEINE. 
 
 When excess of narceine is digested, with frequent agita- 
 tion, for twenty-four hours in water at the ordinary temperature, 
 it requires 1,660 parts of the liquid for solution. It is much 
 more soluble in hot water, from which the excess slowly sepa- 
 rates as the solution cools. One part of the alkaloid dissolves 
 in five hundred parts of water as soon as the mixture is brought 
 to the boiling temperature ; this solution may then be exposed 
 for half an hour or longer to a temperature of 60°, before crys- 
 tals begin to separate. A concentrated aqueous solution of 
 narceine has no action upon reddened litmus. Absolute ether, 
 under the foregoing conditions, dissolved one part of narceine 
 in 4,066 parts of the liquid. Chloroform, under similar circum- 
 stances, dissolved one part in 7,950 parts of liquid. It is much 
 more soluble in alcohol than in water, and is also somewhat sol- 
 uble in dilute solutions of the caustic alkalies. 
 ■■ In the following investigations, the 100th solutions were ob- 
 tained by the aid of hydrochloric acid and a gentle heat ; the 
 more dilute solutions were prepared by dissolving the narceine, 
 when necessary by the aid of heat, directly in distilled water. 
 A 100th solution of narceine in the form of chloride, unless 
 maintained at a gentle temperature, soon becomes filled with a 
 network of long, delicate crystalline needles. 
 
 1. Iodine in Iodide of Potassium, 
 
 A solution of iodine in iodide of potassium produces in solu- 
 tion of narceine a reddish-yellow precipitate, which almost im- 
 mediately becomes crystalline. The precipitate is slowly soluble 
 in large excess of acetic acid. 
 
 !■ Too grain of narceine, in one grain of water, yields a very 
 copious deposit, which very soon becomes a mass of crys- 
 talline needles and tufts ; at the same time, the mixture 
 acquires a blue color. The precipitate is readily soluble 
 in alcohol, from which it soon again separates in the crys- 
 talline form. 
 2. T7oo"o grain, yields a copious precipitate, which soon changes 
 to exceedingly delicate crystalline tufts, Plate IX, fig. 3. 
 After a time, the mixture acquires a more or less blue color. 
 
GOLD AND' PLATINUM TESTS. . 523 
 
 3. 5,000 grain, after a time, yields some few crystalline tufts, 
 of the forms just illustrated. 
 The production of these crystalline tufts is quite peculiar to 
 solutions of narceine. 
 
 2. Bromine in Bromohydric Acid. 
 
 A solution of bromine in bromohydric acid throws down from 
 solutions of narceine, a bright yellow, amorphous precipitate, 
 which after a time dissolves, but is reproduced upon further 
 addition of the reagent. The precipitate is soluble in acetic 
 acid and in alcohol. 
 
 !• Too grain of narceine, in one grain of water, yields a very 
 copious precipitate. 
 
 2. i.Joo grain : a copious deposit. 
 
 3. 1 0.0 grain, yields after a very little time, a quite fair, yel- 
 
 low precipitate. 
 
 3. Chloride of Gold. 
 
 Terchloride of gold occasions in solutions of narceine, a yel- 
 low flocculent precipitate, which remains unchanged in color. 
 The precipitate is soluble in the mixture upon the application 
 of heat, and reproduced unchanged as the solution cools. It is 
 readily soluble to a clear solution in caustic potash. 
 1- Too" grain of narceine, yields a very copious deposit. 
 
 2. i.Joo grain : a very good precipitate. 
 
 3. 10,0 grain, yields after a little time, a perceptible turbid- 
 
 ity, which soon becomes quite well marked. 
 
 4. Bichloride of Platinum. 
 
 This reagent precipitates from solutions of narceine a yellow 
 flocculent deposit, which is readily soluble in acids. After a 
 time, the precipitate yields granules and crystalline needles. 
 
 1. Yoo grain of narceine, yields a very good deposit. 
 
 2. ToT grain : a very fair precipitate. 
 
 3. TTFoo grain : no indication. 
 
524 OPIANYL. 
 
 5. Carbazotic Acid. 
 
 An alcoholic solution of carbazotic acid causes in solutions 
 of narceine, a yellow amorphous precipitate, which is readily 
 soluble in acetic acid. 
 
 1. You grain of narceine, yields a copious deposit. 
 
 2. 1,0^0 grain: a good precipitate. 
 
 3. s7o"oo grain, yields after a little, time, a quite satisfactory 
 
 deposit. 
 
 6. Bichromate of Potash. 
 
 Bichromate of potash produces in strong solutions of nar- 
 ceine a yellow amorphous precipitate, which soon becomes crys- 
 talline. 
 
 1 . j-g-Q grain of narceine, yields a very copious precipitate, which 
 
 almost immediately becomes a mass of crystals. 
 
 2. 5^ grain, yields a very good crystalline deposit, Plate 
 
 IX, fig. 4. 
 Frotochromate of potash produces, in solutions of the alka- 
 loid, much the same results as the bichromate. 
 
 Iodide of potassium, sulphocyanide of potassium, corrosive 
 sublimate, ferro-, and ferri-cyanide of potassium produce no 
 precipitate in even saturated aqueous solutions of narceine. 
 
 VII. Opiantl. 
 
 History. — Opianyl, or Meconine, as it was formerly named, 
 was discovered, in 1826, by M. Dublanc, but first described by 
 M. Couerbe, in 1832. It is a neutral, crystallisable substance, 
 and forms less than one per cent, of opium. Its formula, as 
 first determined by Couerbe, and afterwards confirmed both by 
 Regnault and by Anderson, is CzoHioOs. It, therefore, differs 
 from the alkaloids in not containing nitrogen. 
 
 Preparation. — Opianyl may be obtained from the mother- 
 liquor from which narceine has been prepared, by agitating it 
 with successive portions of ether, as long as this liquid becomes 
 
CHEMICAL PROPERTIES. 525 
 
 colored. The united ethereal solutions are then evaporated, and 
 the brown syrup treated with dilute hydrochloric acid, which 
 dissolves the papaverine, while the opianyl, together with some 
 resin, remains. The opianyl is then crystallised several times 
 from boiling water, with the addition of animal charcoal, when 
 it finally separates in colorless needles. It may also be obtained 
 by acting upon narcotine with nitric acid. 
 
 Physiological Effects. — From the few experiments made with 
 this substance, it would seem to be inert. 
 
 Chemical Peopeeties. — Opianyl readily crystallises in the 
 form of long, colorless, six-sided prisms, or as delicate needles ; 
 it has a somewhat bitter taste. At a moderate heat, it fuses to 
 a colorless liquid, which upon cooling, solidifies to a radiated 
 crystalline mass; at higher temperatures, it is dissipated in the 
 form of white fumes. When cautiously heated in a glass tube, 
 it sublimes in beautiful crystals (Anderson). Although a per- 
 fectly neutral body, it is soluble in acids. 
 
 The following observations are based upon the examination 
 of a single specimen of opianyl, prepared by E. Merck. It 
 was in the form of delicate, snow-white crystals. 
 
 Concentrated sulphuric acid dissolves it to a colorless solu- 
 tion, which when heated acquires either a beautiful blue or 
 purple color, the hue depending upon the relative quantity of 
 acid employed (see post) ; the cooled mixture, upon the addition 
 of water, becomes reddish-brown and yields a brownish precip- 
 itate. Nitric acid also dissolves it to a colorless solution, which 
 on being heated acquires a more or less yellow color, and on 
 evaporation leaves a colorless crystalline residue. It is also sol- 
 uble in concentrated hydrochloric acid without change of color, 
 even upon the application of heat. 
 
 When excess of opianyl is digested in water for several 
 hours, with frequent agitation, at a temperature of about 60° F., 
 one part dissolves in 515 parts of the liquid. According to 
 Couerbe, it dissolves in 265 parts of cold water ; while Ander- 
 son states that at 60°, it requires 700 parts of this liquid for 
 solution. It is much more freely soluble in hot water, but much 
 of the excess separates in its crystalline state as soon as the 
 solution begins to cool. When excess of opianyl is boiled with 
 
526 OPIANYL. 
 
 water, it melts imder the liquid; yet, according to Anderson, 
 when in its dry state, it requires a temperature of 230° F. for 
 its fusion. Absolute ether, when in contact with excess of 
 opianyl for several hours, at the ordinary temperature, dissolves 
 one part in 136 parts of the liquid. Chloroform dissolves it in 
 all proportions. It is also readily soluble in alcohol; but it is 
 not more soluble in solutions of the caustic alkalies than in 
 pure water. 
 
 In the following investigations, the opianyl was dissolved, 
 when necessary by the aid of a very gentle heat, in pure water. 
 
 1. Iodine in Iodide of Potassium. 
 
 A solution of iodine in iodide of potassium produces in aque- 
 ous solutions of opianyl, a yellowish-brown amorphous precip- 
 itate, which quickly becomes quite dark-brown, and then changes 
 to a mass of yellow crystals, which in their dry state resemble 
 spangles of gold-dust. The precipitate, is readily soluble in 
 alcohol. 
 !• ToT grain of opianyl, in one grain of water, yields a very 
 
 copious precipitate, which very soon becomes converted 
 
 into yellow crystals, Plate IX, fig. 5. 
 
 2. i,Joo grain: a good, yellowish-brown deposit, which soon 
 
 darkens. 
 
 3. 2,500 grain, yields after a little time, a slight cloudiness, fol- 
 
 lowed by the precipitation of dark-colored granules. 
 The reaction of this reagent is quite peculiar to solutions of 
 opianyl. 
 
 2. Bromine in Sromohydric Acid. 
 
 This reagent precipitates from solutions of opianyl a deposit 
 of short needles, and groups of hair-like crystals. The precip- 
 itate is insoluble in acetic acid, and but slowly soluble in large 
 excess of alcohol. 
 !• sw grain: after a few moments, crystals begin to form, and 
 
 soon there is a quite copious deposit, Plate IX, fig. 6 ; 
 
 after a time^, the mixture becomes a colorless mass of 
 
 crystals. 
 
SULPHURIC ACID TEST. 527 
 
 2. 1,000 grain : in a very little while, a quite good crystalline 
 
 deposit. 
 3- 2,5 grain, yields after a little time, a very satisfactory 
 
 crystalline precipitate. 
 The production of this crystalline precipitate is quite char- 
 acteristic of opianyl. 
 
 3. Sulphuric Acid and Heat. 
 
 When a small quantity of opianyl in its solid state, is heated 
 with a very minute portion of concentrated sulphuric acid, it 
 yields an intense blue color, which, as the heat is increased, 
 changes to purple ; when a larger quantity of acid is employed, 
 the heated mixture acquires a transient blue color, which passes 
 to purple ; while with a still larger quantity, the mixture, when 
 heated, assumes at once a beautiful purple color. This experi- 
 ment may be performed in a thin, annealed watch-glass. 
 !■ "so~o grain of opianyl, when moistened with a very small 
 quantity of the acid, and heated, yields an intense blue 
 coloration. 
 
 2. TTo^oo grain : much the same as 1 . For the success of this 
 
 reaction it is essential that the least possible quantity of 
 acid be employed. This is best attained by touching the 
 deposit with a glass rod moistened with the acid ; the mix- 
 ture is then heated over the flame of a spirit-lamp, until 
 it begins to assume a blue color — ^which does not usually 
 occur until vapors of the acid are evolved — when the heat 
 is withdrawn. 
 
 3. 10,000 grain, when treated as just described, yields very 
 
 satisfactory results. 
 
 4. 2 5,0 grain: if the deposit be not distributed over a large 
 
 space, it yields a very distinct blue coloration. 
 With a very small quantity of the acid, a blue color may be 
 obtained from a much less quantity of opianyl than will yield a 
 purple color with a larger quantity of the acid. The produc- 
 tion of this blue coloration is quite characteristic of opianyl. 
 Narcotine when heated with a small quantity of sulphuric acid 
 yields a purple mixture, which darkens as the heat is increased. 
 
528 OPIANYL. 
 
 So, also, a sulphuric acid solution of codeine, when heated, 
 acquires a purple color. 
 
 A sulphuric acid solution of opianyl, when stirred with a 
 few crystals of nitrate of potash, yields a yellow mixture, soon 
 changing to a beautiful scarlet-orange color, which but slowly 
 fades. Almost the least visible quantity of the substance when 
 treated in this manner, with a very small quantity of the acid 
 and nitre, yields very satisfactory results. On heating the mix- 
 ture, the orange color is changed to yellow. In these reactions, 
 opianyl somewhat resembles narcotine. 
 
 As opianyl forms no definite combinations with acids nor 
 metallic oxides, it is not precipitated by the ordinary reagents. 
 According to Couerbe, it yields a crystalline precipitate with 
 basic acetate of lead ; but, like Anderson, we failed to obtain 
 a precipitate by this reagent. 
 
NUX VOMICA. 529 
 
 OHAPTEE III. 
 
 NUX VOMICA, STRYCHNINE, BRUCINE. 
 
 I. Nux Vomica. 
 
 History and Composition. — Nux vomica is the seed of the 
 Strychnos nux vomica, a tree found native in the East Indies, 
 and the island of Ceylon. The seeds are flat, nearly round, 
 and something less than an inch in diameter, being slightly 
 concave on one side, and convex on the other, and covered 
 vrith short, silky, greyish or yellbwish hairs, which are attached 
 to an investing membrane, and incline towards the circumfer- 
 ence of the seed. The seeds are very hard, difficult to pul- 
 verise, and when chewed have an intensely bitter taste, but 
 they are destitute of any well-marked odor. In its powdered 
 state, nux vomica has a yellowish-grey color, and a peculiar 
 odor, not very unlike that of liquorice. 
 
 Nux vomica possesses powerful poisonous properties, due to 
 the presence of the alkaloids, strychnine and hrucine, which 
 exist in the seed in combination with a peculiar organic acid, 
 known as strychnic, or igasuric acid. The seeds also contain, 
 according to the analysis of PeUetier and Caventou, yellow 
 coloring matter, gum, a waxy substance, starch, a concrete oil, 
 woody fiber, and earthy salts. A third alkaloid, under the name 
 of igasurine, has more recently been described by M. Desnoix. 
 The powdered seeds yield their active properties to water, but 
 much more freely to alcohol. Poisoning by this substance, has 
 been of quite frequent occurrence. 
 
 Symptoms. — The symptoms produced by poisonous doses of 
 nux vomica, or either of its active alkaloids, are very uniform 
 in their nature, and quite peculiar. There is at first, a sense 
 of numbness in the extremities, with more or less trembling of 
 
 34 
 
530 NUX VOMICA. 
 
 the muscles, and a feeling of great anxiety. These effects are 
 soon succeeded by violent muscular contractions, in which the 
 limbs are extended and perfectly rigid, the head thrown back, 
 the jaws fixed, the face livid, and the respiration apparently 
 suspended. After a little time, varying from a few moments to 
 some minutes, the convulsive paroxysm subsides, and the patient 
 then feels much exhausted, and is usually extremely sensitive to 
 external impressions. This condition, however, is usually of 
 short duration, the convulsions being succeeded by others, which 
 increase in violence, and speedily run to a fatal termination. In 
 some instances, death takes place during a paroxysm, but more 
 generally, from extreme exhaustion. The intellectual faculties 
 usually remain unaffected, even up to the time of death. The 
 time within which the symptoms first manifest themselves, is 
 subject to considerable variation, they occurring in some in- 
 stances almost immediately, and in others being delayed for 
 even more than an hour. 
 
 The following case, reported by Mr. Oilier, and quoted by 
 most toxicological writers, well illustrates the usual effects of 
 nux vomica. A young woman purposely swallowed, in suspen- 
 sion in water, about three drachms of the powder. When seen 
 abovrt half an hour afterwards, she was calm and quite well. 
 But in about ten minutes more, she was seized with a convulsive 
 fit, and in a few minutes afterwards, had another, which was 
 soon succeeded by a third: the duration of these paroxysms 
 was about two minutes each. During the attacks, the whole 
 body was extended and rigid, the legs widely separated, the 
 face and hands livid, and the muscles of the former violently 
 convulsed: no pulse or breathing could be perceived. In the 
 intervals, she was quite sensible; complained of being sick, and 
 made many attempts to vomit; had incessant thirst, a very 
 quick and feeble pulse, and perspired freely. A fourth attack 
 soon followed, in which the whole body was extended to the 
 utmost and rigidly stiff. She now fell into a state of asphyxia, 
 relaxed her grasp, white foam issued from her mouth, the 
 expression of the countenance became most frightful, and death 
 ensued in about an hour after the poison had been taken. 
 (London Med. Repository, vol. xix, p. 448.) 
 
PERIOD WHEN FATAL. 531 
 
 In a non-fatal case, related by Dr. Basedow, of Merseburg, 
 the following symptoms were observed. A young lady took, 
 by mistake, a tablespoonful of th'<b powdered drug. She was 
 almost instantly deprived of the power of walking, and fell 
 down, but still retained her consciousness. When first seen by 
 Dr. Basedow, almost immediately afterwards, her countenance 
 was pale, and exhibited alternately an expression of indifi'erence 
 and anxiety ; the eyes were wide open, and the pupils con- 
 tracted. The respiration was irregular and short ; the pulse 
 irregular and small, and the skin cool. The forearms were 
 constantly in a half bent position, and the hands and fingers 
 afifected with convulsive twitches ; but the legs were motionless, 
 and rigid, all the muscles being hard and tetanically contracted. 
 The patient had not the slightest pain or sickness ; but her 
 breathing became every moment more difficult, and she com- 
 plained of impending suffocation. An emetic was now adminis- 
 tered, and its action followed by the exhibition of small doses 
 of a mixture of oil of turpentine and sulphuric ether. The 
 dyspnoea gradually subsided, and in about six hours after the 
 poison had been taken, the tetanic spasms of the muscles of the 
 legs, as well as the convulsive movements of the hands, had 
 ceased, and the respiration was free ; but the patient complained 
 of a sense of bruising over the whole body, and pain in the 
 limbs, for some days afterwards. (New York Med. and Phys. 
 Journal, No. xxx, p. 448.) 
 
 In some few of the recorded cases of poisoning by this sub- 
 stance, the first symptoms observed were nausea and vomiting ; 
 while in others, the tetanic symptoms were followed by purging, 
 and inflammation of the stomach and bowels. 
 
 Period when Fatal. — In fatal poisoning by nux vomica, 
 death usually takes place within a very few hours after the 
 poison has been taken ; but life has been prolonged for some 
 days. In a case cited by Dr. Christison, in which a man swal- 
 lowed an unknown quantity of the powder, mixed with beer, 
 death occurred in fifteen minutes after the poison had been 
 taken. (On Poisons, p. 686.) Several instances are related in 
 which death took place in from one to two hours. On the other 
 hand, in a case cited by Orfila (Toxicology, vol. ii, p. 605), a 
 
532 NUX VOMICA. 
 
 man swallowed a considerable quantity of the powder, and 
 almost immediately was seized with violent convulsions ; yet 
 death did not occur until th€ fourth day. 
 
 Fatal Quantity. — In a case quoted by Dr. Christison, an old 
 woman, who was using an alcoholic extract of nux vomica for 
 palsy, took an overdose of three grains, which soon produced 
 violent tetanic spasms, followed by an attack of inflammation of 
 the stomach and intestines, and death on the third day. The 
 quantity of the crude powder represented by the extract taken 
 in this case, is quite uncertain. The same writer cites another 
 instance, related by Hoffmann, in which thirty grains of the 
 crude powder, taken in two equally divided doses, caused death. 
 (On Poisons, p. 689.) Dr. Taylor mentions two cases, in each 
 of which fifty grains of the powder proved fatal : in one of 
 these, death took place in an hour. (On Poisons, p. 767.) In 
 another instance, two drachms caused death in about two hours. 
 Recovery has not unfrequently taken place after large quanti- 
 ties of nux vomica had been swallowed ;. and Prof. G. B. Wood 
 states that fifty grains have been given with little or no effect. 
 
 Treatment. — The stomach should be emptied as speedily 
 as possible, either by means of the stomach-pump or the ad- 
 ministration of an emetic. Since the poison, when taken in the 
 form of powder, sometimes adheres tenaciously to the walls of 
 the stomach, the use of the pump, or the action of the emetic, 
 should be continued for some time. Various chemical antidotes 
 have been advised, but none of these are reliable. After the 
 contents of the stomach have been evacuated, vegetable astrin- 
 gents or a solution of iodine in iodide of potassium, might be 
 found useful, for the purpose of neutralising any remaining 'por- 
 tions of the poison. Other methods of treatment will be re- 
 ferred to hereafter, when considering the antidotes for poisoning 
 by strychnine. 
 
 Post-mortem Appearances. — Nux vomica may occasion 
 death without leaving any well-marked morbid change in any 
 part of the body. In Mr. Ollier's case, before cited, in which 
 death took place in an hour, five hours after death, the body 
 was as straight and stiff as a statue, so if one of the hands 
 was moved the whole body moved with it. On dissection, the 
 
CHEMICAL PROPERTIES. 533 
 
 stomach was found nearly natural, the blood-vessels of the brain 
 congested, and the heart of a pale color, empty, and flaccid. 
 In another case, in which about an ounce of the poison had 
 been taken and proved rapidly fatal, large quantities of a san- 
 guinolent fluid were found in the cavities of the brain, and 
 between its membranes ; and the lungs, as well as the heart, 
 were highly gorged with black fluid blood. The stomach was 
 healthy, except a patch of the mucous membrane in the larger 
 curvature of the organ, which was evidently inflamed, and of a 
 deep red color, the intensity diminishing from the circumference 
 to the centre. 
 
 In the case cited from Orfila, in which death did not take 
 place until the fourth day, the following appearances were ob- 
 served forty-eight hours after death. The body was consider- 
 ably rigid, and of a violet hue. The lateral ventricles of the 
 brain, and the cavity of the arachnoid membrane, contained 
 large quantities of serum ; but no appreciable alteration was 
 detected either in the meninges or cerebral substance. The 
 internal surface of the stomach presented at different points, a 
 color which varied from red to deep black ; and the duodenum 
 and upper portions of the small intestines were manifestly in- 
 flamed. The lungs were gorged with blood ; the heart was 
 natural. 
 
 Chemical Peoperties. 
 
 The physical properties of nux vomica, when in its solid 
 state, readily distinguish it from all other substances. If a small 
 portion of the powdered seed be moistened with a drop of water, 
 and examined under a low power of the microscope, the broken 
 fibrous hairs may be readily distinguished, they apparently 
 forming a large portion of the powder. The hairs acquire a 
 yellow color upon the addition of a solution of iodine in iodide 
 of potassium ; when the crude powder is thus treated, it assumes 
 a deep brown color. When touched with a drop of concentrated 
 nitric acid, the powder acquires a deep orange-red color, which 
 is slowly discharged by a solution of protochloride of tin. Con- 
 centrated sulphuric acid causes it, like most vegetable powders, 
 to assume a brownish, then black color. Hydrochloric acid 
 
534 STRYCHNINE. 
 
 produces little or no change. When moderately heated, the 
 powder evolves dense white fumes, having a peculiar odor; at 
 higher temperatures, it becomes ignited. 
 
 When powdered nux vomica is macerated in water or diluted 
 alcohol, the liquid takes up the strychnine and brucine, as salts 
 of their peculiar acid, and more or less coloring matter ; this 
 extraction is much facilitated by a moderate heat. The solu- 
 tion thus obtained, has an intensely bitter taste, strikes a red 
 color with nitric acid, and yields a copious reddish-brown pre- 
 cipitate with a solution of iodine in iodide of potassium. It 
 acquires a greenish hue when treated with a solution of a per- 
 salt of iron ; amraonio-sulphate of copper produces a somewhat 
 similar coloration, and, after a time, a greenish-white precipi- 
 tate. Tannic acid throws down from the solution, a copious, 
 dirty-white precipitate. 
 
 It is obvious that there can be no chemical test by which 
 the presence of nux vomica as a whole, when in a complex or- 
 ganic mixture, can be directly shown ; but this may be inferred 
 by proving the presence of one or more of its peculiar princi- 
 ples. Of these principles, strychnine is usually much the most 
 easy of detection. Since, however, this alkaloid is so frequently 
 met with in its pure state, or that of some of its salts, its mere 
 detection would not, independent of other circumstances, prove 
 the presence of nux vomica. The methods for the separation 
 of strychnine and brucine from organic mixtures of the crude 
 drug, are the same as those for their recovery from organic 
 mixtures in general, as will be pointed out hereafter under the 
 special consideration of these alkaloids. 
 
 II. Strychnine. 
 
 History. — Strychnine, or strychnia, was discovered, in 1818, 
 by Pelletier and Caventou, both in the seed of Strychnos nux 
 vomica and the St. Ignatius' hean, which latter is the seed of 
 the Strychnos Ignatii. Thus far it has only been found in five 
 species of the Strychnos genus of plants, and in most of these 
 it is accompanied by brucine. Several of the species of this 
 genus of plants contain neither strychnine nor brucine. The ' 
 
PREPARATION. 535 
 
 composition of strychnine, in its anhydrous state, according 
 to Regnault, and since confirmed by Nicholson and Abel, is 
 C42H22N2O4. According to most analysts, it forms something 
 less than one-half per cent, by weight of nux vomica ; more 
 recently, however, Mr. Horsley states that he obtained about 
 one per cent, of the alkaloid from that substance. From the 
 St. Ignatius' bean, Pelletier and Caventou obtained from one to 
 two per cent, of the alkaloid. 
 
 Preparation. — Strychnine may be obtained from nux vomica 
 by the following process. The rasped seeds are digested for 
 twenty-four hours in water acidulated with hydrochloric acid, 
 the decoction then strained through linen, the strained liquid 
 concentrated to a small volume, and then precipitated with milk 
 of lime ; the precipitate thus produced is collected on a cloth, 
 washed with cold water, then dried, and the pulverised mass 
 exhausted with successive portions of alcohol, until deprived of 
 its bitterness. The mixed alcoholic liquids are concentrated on 
 a water-bath, and then treated with water containing a little 
 sulphuric acid, by which the strychnine will be dissolved in the 
 form of sulphate. This solution is boiled with animal charcoal, 
 filtered, concentrated to a small volume, and the alkaloidal sul- 
 phate allowed to separate by crystallisation. The crystals may 
 now be dissolved in pure water, and the alkaloid precipitated 
 by slight excess of ammonia, then collected on a filter, washed 
 with cold water, and allowed to dry. As thus obtained, strych- 
 nine usually contains more or less brucine. 
 
 Mr. Horsley's method for preparing the alkaloid consists in 
 first exhausting powdered nux vomica by repeated extractions 
 with water strongly acidulated with acetic acid. The united 
 acid liquids are then filtered, and the filtrate evaporated to a 
 syrupy consistency. The cooled residue is diluted with water, 
 slight excess of ammonia added, and the mixture allowed to 
 repose for one or two days. Any crystals thus obtained, are 
 washed, dried, then redissolved in water containing acetic 
 acid, and the solution filtered. The liquid is now treated 
 with a solution of chromate of potash, by which the alkaloid 
 is precipitated as chromate of strychnia. This is collected, 
 washed, then digested in a solution of ammonia, when, the 
 
536 STRYCHNINE. 
 
 chromic acid uniting with the ammonia, the strychnine sepa- 
 rates in its pure state. 
 
 Strychnine is one of the most virulent poisons known. It is 
 found in the shops both in its free state and in the form of some 
 of its salts ; its principal salts are the sulphate, chloride, or mu- 
 riate, and the acetate. The ordinary medicinal dose of strych- 
 nine, or of any of its saline combinations, is about one-sixteenth 
 of a grain. 
 
 Symptoms. — These are the same in kind as those produced 
 by nux vomica, but they usually manifest themselves even more 
 promptly. The first symptoms are usually a sense of oppres- 
 sion and great anxiety, with quivering and spasmodic move- 
 ments of the muscles of the extremities. These effects are 
 sooner or later succeeded by violent muscular convulsions, in 
 which the head is thrown back, the whole body rigidly stiff, 
 the extremities extended, the hands firmly clenched, and the 
 feet arched. In this state, the jaws are usually firmly closed, 
 the face livid, the eyes prominent, the pupils dilated, and often 
 foam issues from the mouth ; the muscles of the chest and dia- 
 phragm are also strongly contracted, and the respiration appar- 
 ently arrested ; the pulse is either very rapid or altogether 
 imperceptible. In a little time, varying from less than a minute 
 to several minutes, this tetanic condition usually entirely disap- 
 pears, and there is a state of calm. During this state the 
 patient feels extremely weak, usually experiences great thirst, 
 and is sometimes inclined to sleep. After a little time, how- 
 ever, the system again becomes excited, the special senses being 
 exceedingly acute, and frequently there is a sense of impending 
 death. A second paroxysm may now be induced by very slight 
 causes, or it may appear without any apparent cause. Not 
 unfrequently the patient is perfectly conscious of the approach 
 of the attack, and desires to be held or rubbed. After a suc- 
 cession of attacks, varying from two to several, death takes 
 place either during a paroxysm from asphyxia, or, more fre- 
 quently, soon after from complete exhaustion. The interval 
 between the paroxysms has varied from a few minutes to more 
 than half an hour. The intellect usually remains clear up to 
 the time of death. 
 
PHYSIOLOGICAL EFFECTS. 537 
 
 In a case reported by Dr. Blumhardt, in which a young 
 man, for the purpose of self-destruction, swallowed forty grains 
 of strychnine, the following symptoms were observed. The pa- 
 tient soon experienced great anxiety and agitation, and after 
 the lapse of fifteen minutes, an emetic having been adminis- 
 tered, but with the effect of producing only slight vomiting, he 
 lay stiff upon his back, with the head somewhat bentJbackwards; 
 the lower extremities were perfectly stiff, but the upper still 
 free ; the countenance was pale and haggard ; the pulse quick 
 and contracted. He still spoke Avith a firm voice and in a col- 
 lected manner, but trismus was evidently commencing. The 
 attacks soon became more violent, and the spasms extended to 
 the muscles of the chest ; the thorax appeared compressed, and 
 the respiration was impeded. The paroxysms were now re- 
 peated, at intervals of about a minute, for a short time, when 
 the whole body became affected, and as stiff as a board. The 
 suffocation was now extreme ; the jaws firmly locked together ; 
 the upper extremities firmly flexed at the elbow-joints and ap- 
 plied across the chest ; the lower extremities extended and stiff, 
 and the soles of the feet concave. By degrees the respiration 
 became more unequal, and finally ceased ; the pulse became 
 imperceptible ; the skin of a dusky blue color ; the face deep 
 purple ; the eyes prominent, and the pupils dilated and insensi- 
 ble. All signs of consciousness soon disappeared, and the patient 
 lay for a few minutes without motion, in a state of universal 
 tetanus. A remission of the convulsions now suddenly mani- 
 fested itself; the limbs became relaxed, and after a long deep- 
 drawn inspiration the pulsations of the heart and arteries were 
 again perceptible ; consciousness and the power of speech were 
 also restored, but the articulation was imperfect. After about 
 fifteen minutes, the patient was again seized with a shivering 
 fit, followed by general tetanus, which soon terminated in a 
 state of asphyxia, and death took place an hour and a half 
 after the poison had been taken. (American Medical Intelli- 
 gencer, vol. ii, p. 28.) 
 
 The time within which the symptoms first manifest them- 
 selves has varied from a few minutes to some hours ; but they 
 do not often appear much before fifteen minutes, nor are they 
 
538 STRYCHNINE. 
 
 often delayed much beyond half an hour. In a recent case, 
 reported by Dr. G. F. Barker, a young, healthy, married woman 
 had administered to her with criminal intent, not exceeding six 
 grains of strychnine, and violent symptoms were present in 
 three minutes afterwards ; these were succeeded by several con- 
 vulsive paroxysms, and death during a paroxysm in thirty min- 
 utes after the poison had been taken. (Amer. Jour. Med. Sci., 
 Oct., 1864, p. 399.) In this instance, the strychnine was taken 
 in its dry state into the mouth, and washed down with water. 
 This is, perhaps, the most rapid case, in regard to the appear- 
 ance of the symptoms, yet recorded. In the case of Dr. 
 Warner, of Vermont, who, by mistake, took, it is believed, 
 something less than half a grain of the poison, well-marked 
 symptoms were present within five minutes, and death occurred 
 in about eighteen minutes. 
 
 On the other hand. Dr. H. G. Thomas, of Alliance, Ohio, 
 has reported a case in which a man swallowed five grains of 
 strychnine, and one hour and three-quarters elapsed before any 
 symptoms manifested themselves ; and, under the use of emetics, 
 the patient recovered. One of the most remarkable cases of 
 this kind yet recorded, is the following, reported by Dr. T. 
 Anderson. A gentleman took by mistake, believing it to be 
 a salt of morphine, three grains and a half of strychnine, and 
 experienced no particular symptoms until two hours and a half 
 afterwards, when he suddenly fell backwards, but on being 
 immediately raised, he was able to walk home, although ex- 
 ceedingly nervous and alarmed. He soon felt better, and in 
 five hours after taking the dose, he again took a similar quan- 
 tity. In less than ten minutes after taking the last dose, 
 he was seized with violent tetanic spasms, which continued, 
 with the usual intermissions, for several hours, after which he 
 entirely recovered. (Amer. Jour. Med. Sci., April, 1848, p. 
 562.) The form in which the poison is taken, and the condi- 
 tion of the stomach, may to some extent determine the time at 
 which the symptoms first appear; but several instances are 
 recorded in which the symptoms were delayed much beyond 
 the ordinary period, even under conditions apparently the most 
 favorable for their development. 
 
EFFECTS OF EXTERNAL APPLICATION. 539 
 
 It need hardly be j-emarked that the effects of strychnine 
 may be much modified by the presence of another poison. A 
 case of this kind, in which three grains of strychnine and one 
 drachm of opium were taken and no serious symptoms appeared 
 for nearly twelve hours, has already been mentioned. (Inteo- 
 DUCTION, p. 40.) The following somewhat similar case, may 
 also be cited. A young druggist, with suicidal intent, swal- 
 lowed, at half-past eight o'clock in the evening, between eight 
 and ten grains of nitrate of strychnia in an ounce of bitter- 
 almond water. A little later, he took an additional dose of 
 twelve grains of strychnia. Feeling nothing peculiar, he took 
 at nine o'clock, ten grains of acetate of morphia dissolved in an 
 ounce of bitter-almond water, and then lay down in bed. Ten 
 minutes later, to hasten his death, he poured some chloroform 
 on his pillow. Partial insensibility now manifested itself, and 
 continued for about an hour and a half, when he was seized 
 with violent cramps and cessation of respiration, but without 
 pain. Loss of consciousness then supervened, but he soon 
 revived, and had another attack of convulsions. Emetics, and 
 tannic acid were now administered; and in two days after- 
 wards, no trace of the poisoning remained. (Amer. Jour. Med. 
 Sci., Jan., 1863, p. 259.) Recovery in this case has been 
 ascribed to the fact that the patient, before taking the poison, 
 had partaken freely of a soup made ■ with flour and a species 
 of cranberries. These latter contain tannin, an agent which is 
 said to neutralise strychnine; and the farinaceous matters, by 
 enveloping the poison, may have prevented its absorption. 
 
 The external application of strychnine may be attended with 
 serious, and even fatal consequences. In a case related by Dr. 
 Schuler, something less than the twelfth of a grain of pure 
 strychnine was introduced into the corner of the eye of a man 
 affected with amaurosis. In less than three or four minutes, the 
 patient's face became livid, and he was seized with spastic 
 yawning§ and vertigo. These symptoms increased, and loss of 
 speech and pulse, with convulsive respiration and violent tetanic 
 shocks ensued. Death seemed inevitable, but, under the action 
 of remedies, all the symptoms passed off in less than half an 
 hour. (Amer. Jour. Med. Sci., Oct., 1861, p. 573.) 
 
540 STRYCHNINE. 
 
 It was formerly believed that strychnine, when given in 
 frequently repeated small doses, never accumulates in the sys- 
 tem; but these results have occasionally been observed. Thus, 
 Dr. Dutgher relates a case in which he administered to a 
 middle-aged woman, affected with partial paralysis of the mus- 
 cles of deglutition, the fifth of a grain- of strychnine daily, in 
 divided doses, for nine days, without any effect other than a 
 gradual improvement of the paralytic condition. But on the 
 morning of the tenth day, the patient was seized with pretty 
 severe tetanic spasms, which continued, at intervals of about 
 twenty minutes, for several hours, when they ceased, and the 
 patient recovered, without any vestige of the paralysis remain- 
 ing. (Med. and Surg. Reporter, Philadelphia, July, 1865, p. 2.) 
 It will be observed, that the entire quantity of strychnine taken 
 in this case, did not exceed two grains. 
 
 A fatal case apparently of this kind was communicated, by 
 Mr. Cooper, to the late Dr. Pereira (Mat. Med., vol. ii, p. 548). 
 A Swede, affected with general paralysis, was given one-eighth 
 of a grain of strychnine three times a day for several weeks. 
 The dose was then increased to one-quarter of a grain, and 
 afterwards to half a grain, with the same frequency for many 
 days, without any marked effect. But one morning, the patient 
 was found insensible, the face and chest of a deep purple color; 
 the respiration had ceased, and the whole body was in a state 
 of tetanic spasm and rigid. These symptoms passed off, and 
 the man became apparently sensible; but another paroxysm 
 soon occurred, and proved rapidly fatal. 
 
 In regard to the diagnosis of strychnine poisoning, the only 
 disease with which its symptoms could be confounded is tetanus 
 arising from ordinary causes. But there is rarely any difficulty 
 in determining the true nature of the case. Thus, in poisoning 
 the symptoms appear suddenly in a violent form; the muscles 
 of the hands are the first, and those of the jaws the last to 
 become affected; there is usually a complete intermission in the 
 symptoms; and they rapidly run their course, rarely lasting 
 over a few hours at most. On the other hand, in the disease 
 the symptoms are slowly developed; the muscles of the jaws 
 are the first, and those of the hands the last to become involved; 
 
PERIOD WHEN FATAL. 541 
 
 there is at most only a remission of the rigid state of the sys- 
 tem; and death rarely occurs within twenty-four hours, the 
 case often being protracted for several days. 
 
 Period when Fatal. — A case is recorded, in which a young 
 man, through the ignorance of a druggist, took one grain and 
 two-thirds of strychnine with the same quantity of nux vomica, 
 and "he very soon afterwards complained of some extraordinary 
 sensations, and almost immediately expired." (Amer. Jour. Med. 
 Sci., April, 1854, p. 537.) In a case privately communicated 
 to Dr. Taylor, ten grains of strychnine, given in mistake for 
 sulphate of quinine, proved fatal in ten minutes. (On Poisons, 
 p. 781.) In the case of Dr. Warner, already mentioned, death 
 occurred in about eighteen minutes after the poison had been 
 taken. Dr. Geoghegan, of Dublin, relates an instance in which 
 five grains proved fatal in from twenty to twenty-five minutes; 
 and in Dr. Barker's case, already cited, six grains caused death 
 in about thirty minutes. In a case described by Dr. Theinhart, 
 in which nearly thirty grains of the poison were taken, violent 
 symptoms appeared in about fifteen minutes, and, after four 
 convulsive paroxysms, death occurred in half an hour. (Amer. 
 Jour. Med. Sci., Jan., 1848, p. 303.) 
 
 On the other hand, in the well-known case of Cook, poisoned 
 by Palmer, the symptoms were delayed for nearly an hour, and 
 death occurred in about an hour and a quarter after the poison 
 had been taken. We have elsewhere recorded a case in which 
 a man, named Freet, took an unknown quantity of the poison, 
 and violent symptoms appeared in about half an hour, but death 
 did not take place until an hour later.* In a case described by 
 Dr. Steiner — that of Dr. Gardiner, of Washington City — death 
 did not occur until after the lapse of three hours and a half, 
 although violent symptoms were present shortly after the poison 
 had been taken. (Report on Strychnia, Philadelphia, 1856.) 
 A still more protracted case has recently been reported by Dr. 
 Paley, in which death did not occur until after the lapse of 
 about five hours. (Brit, and For. Med.-Chir. Rev., Oct., 1860, 
 
 *For the details of this case, as also an elaborate review of the legal bearings 
 of poisoning, by Hon. Judge Wm. Lawrence, see Ohio Medical and Surgical 
 Journal, March and May, 1864, pp. 95, 190. 
 
542 STRYCHNINE. 
 
 p. 382.) And Dr. J. J. Eeese, of Philadelphia, reports the 
 case of a woman, in which death was delayed for from five to 
 six hours. (Amer. Jour. Med. Sci., Oct., 1861, p. 409.) At a 
 subsequent trial of this case, as personally informed by Wra. 
 H. Miller, Esq., who was engaged in the trial, it fully appeared 
 in evidence that the deceased had taken from five to six grains 
 of the poison, and death was delayed something over six hours. 
 
 Fatal Quantity. — There seems to be much difiference in the 
 susceptibility of difi'erent persons to the action of strychnine. 
 Dr. Wood mentions an instance in which a lady was thrown 
 into violent and even alarming Ipasms, almost threatening suffo- 
 cation, by one-twelfth of a grain of strychnine. (Therapeutics, 
 vol. i, p. 834.) In a case related by M. Duriau, one-sixth of 
 a grain, taken by a woman, aged twenty-eight years, produced 
 in ten minutes afterwards violent tetanic convulsions, in which 
 the whole body became rigid; similar attacks ensued, at inter- 
 vals of a few minutes between each, and these were succeeded 
 by a sense of burning in the epigastrium and pharynx, and 
 great irritability of the stomach, which lasted for not less than 
 six weeks. (Amer. Jour. Med. Sci., Oct., 1862, p. 562.) In 
 the case of Dr. Warner, it is believed that not over half a 
 grain of sulphate of strychnia had been taken. This seems to 
 be the smallest quantity that has yet proved fatal to an adult. 
 In a case reported by Dr. Ogston, three-quarters of a grain 
 destroyed the life of a man, in three-quarters of an hour; and 
 Dr. Watson relates an instance in which a similar quantity 
 caused the death of a girl, aged twelve years, in about one 
 hour. Mr. Bennett describes a case in which one grain and a 
 half caused the death of a girl, aged thirteen years, in two 
 hours and a half (Lancet, Aug., 1850, p. 462); and Dr. Pereira 
 (Mat. Med., vol. ii, p. 549) cites the instance of a lady, who 
 died in less than two hours from the effects of between two and 
 three grains. 
 
 Recovery has not unfrequently taken place after compara- 
 tively large quantities of strychnine had been taken. A case 
 of this kind in which five grains, and another in which seven 
 grains, taken in two doses of three and a half grains each at an 
 interval of five hours, have already been cited. Wharton and 
 
ANTIDOTES. 543 
 
 Stille quote three instances of recovery in each of which four 
 grains of the poison had been swallowed (Med. Jur., p. 624); 
 and a fourth case of this kind is reported by Dr. Lescher, of 
 Illinois, and a still more recent case by Dr. Waller (Med. and 
 Surg. Reporter, Philadelphia, Oct., 1865, p. 277). In another 
 instance, related by Dr. Givens, a young man swallowed, with 
 suicidal intent, two large pills containing not less than ten or 
 twelve grains of strychnine. Violent tetanic spasms soon en- 
 sued, and continued for five hours. In seven hours, the spasms 
 entirely subsided, leaving the patient quite prostrated, with 
 much distension and tenderness of the epigastrium, and stricture 
 and soreness of the throat, and of the muscular system in gen- 
 eral. These effects gradually passed off, and in less than a 
 week the patient was nearly well. Soon after the patient had 
 taken the poison, vomiting occurred, but it is not certainly 
 known that the pills were ejected. (Brit, and For. Med.-Chir. 
 Rev., April, 1857, p. 502.) In a case recently reported by Dr. 
 Wilson (Am. Jour. Med. Sci., July, 1864, p. 70), a young man 
 twenty-two years of age, recovered in about fifteen hours, 
 although it is believed that he had taken forty grains of strych- 
 nine. There is, however, in this instance, much uncertainty as 
 to the quantity of poison really taken ; and, moreover, there 
 seems to have been very early vomiting. In a still more recent 
 case, reported by Dr. Clark, a man laboring under delirium 
 tremens, swallowed over ttventy grains of the poison, and eight- 
 een hours afterwards he was convalescent. (Buffalo Med. and 
 Surg. Jour., Nov., 1866, p. 135.) In this case, also, there was 
 early vomiting. After the action of the emetics, the patient 
 was kept under the influence of chloroform for eight consec- 
 utive hours, during which time all attempts to suspend its use 
 were attended with a recurrence of the convulsions. 
 
 Treatment. — This consists in the speedy administration of 
 an emetic or the employment of the stomach-pump. As an 
 . emetic, finely-powdered mustard or sulphate of zinc may be 
 employed. The action of the emetic should be aided by the free 
 use of warm demulcent drinks. On account of the difficulty of 
 swallowing or the rigid state of the jaws, it is sometimes impos- 
 sible to resort to the use of emetics or the stomach-pump. Of 
 
544 STRYCHNINE. 
 
 the various remedies that have been proposed, the internal ad- 
 ministration of chloroform, as first employed by Dr. Dresbach, 
 of Tiffin, Ohio, seems to be much the most efficient. In a case 
 in which a man had by mistake swallowed a solution of three 
 grains of strychnine, and most violent symptoms were present 
 in twenty minutes. Dr. Dresbach administered two drachms of 
 chloroform, and there was complete relief in less than twenty 
 minutes afterwards.' (Amer. Jour. Med. Sci., April, 1850, p. 
 546.) In another instance, related by Dr. J. E. Smith, the 
 inhalation of the vapor of chloroform was attended with similar 
 results. (Ibid., July, 1860, p. 278.) Another case of this kind, 
 in which four grains of strychnine had been taken, is reported 
 by Dr. Bly. (New York Jour, of Med., Nov., 1859, p. 422.) 
 So, also, in a case communicated to Dr. Wood, in which a 
 robust young man had taken four grains of the poison and was 
 seized with the most violent tetanic spasms, complete recovery 
 took place under the use of chloroform, given both internally 
 and by 'inhalation. (U. S. Dispensatory, 1865, p. 1357.) In 
 this case, it is stated that it was necessary to keep the patient 
 under the influence of the chloroform for thirteen consecutive 
 hours, during which two pounds were consumed by inhalation. 
 Two drops were given every five minutes, by the stomach, 
 when the mouth could be opened. 
 
 As a chemical antidote, tannic acid has been strongly ad- 
 vised; and Dr. Kurzak, of Vienna, has recently performed a 
 series of experiments upon inferior animals, from which it would 
 appear that this substance, if administered early, has the prop- 
 erty of suspending the action of the poison. He states that 
 about twenty-five parts of tannin are required for one part of 
 strychnine. In the absence of tannin in its pure form, a strong 
 infusion of powdered gall-nuts or of green tea might be exhib- 
 ited. (North American Med.-Chir. Rev., July, 1860.) The 
 utility of this acid 'is supposed to depend upon its uniting with 
 the poison to form tannate of strychnia, which is insoluble in. 
 water, but readily soluble in acids. M. Bouchardat recommends, 
 as an antidote, a solution of iodine in iodide of potassium. The 
 precipitate produced by this mixture, is somewhat less soluble 
 in diluted acids than that occasioned by tannic acid. It need 
 
ANTIDOTES. 545 
 
 hardly be remarked that neither of these substances should be 
 relied on to the exclusion of emetics, or the stomach-pump. 
 Among the other substances that have been recommended as 
 antidotes, may be mentioned chlorine, bromine, animal charcoal, 
 camphor, and lard, or fat. A case in which four grains of 
 strychnine had been taken and recovery took place under the 
 use of emetics and camphor, is related by Dr. Rochester (Buf- 
 falo Medical Journal, March, 1856). 
 
 Upon physiological grounds. Professor Houghton was led to 
 believe that strychnine and nicotine (the active principle of 
 tobacco) might be mutually antidotal, and he cites a few experi- 
 ments on frogs in support of this view. And Dr. O'Reilly, of 
 St. Louis, has related an instance in which, acting upon this 
 suggestion, he administered, in divided doses, an infusion of an 
 ounce and a quarter of tobacco to a man who had taken six 
 grains of strychnine, and the patient recovered. (Brit, and For. 
 Med.-Chir. Review, Oct., 1859, p. 387.) Since, however, in 
 this instance, previous to the administration of the alleged anti- 
 dote, an emetic had been given and operated, it is not certain 
 that the recovery was in any way due to the effects of the 
 tobacco. Another instance in which an infusion of tobacco was 
 employed, and the patient recovered has very recently been 
 reported by Dr. Chevers, of Calcutta. (Ibid., Jan., 1867, p. 
 243.) But in this instance, also, there seems to have been vom- 
 iting prior to the administration of the tobacco ; and, moreover, 
 it appears that the patient, a girl aged eleven years, had swal- 
 lowed only a comparatively small quantity, perhaps very much 
 less than one grain, of the poison. 
 
 For the purpose of testing the antidotal properties of nicot- 
 ine, we administered to each of thirteen healthy cats, half a 
 grain of pure strychnine, the poison being passed in solution 
 into the stomach by means of a stomach-tube. In some in- 
 stances, as soon as symptoms of the poison appeared, an infusion 
 of twenty grains of tobacco-leaves was administered, in the same 
 manner as the poison; whilst in others, the tobacco-infusion 
 was given along with the strychnine, the two solutions being 
 thoroughly mixed. In some few cases, the dose of tobacco was 
 repeated. As the result of these experiments : one of the 
 
 35 
 
546 STRYCHNINE. 
 
 animals, which had taken the mixed solutions, immediately fell 
 prostrate, bresithed with difficulty, in three minutes voided urine, 
 in eight minutes vomited a frothy mucus, and in ten minutes 
 was able to run, with, however, a stiff gait ; after an hour, the 
 animal appeared perfectly well, excepting a slight stiifness in 
 walking. With this single exception, all the animals died, and 
 in most instances within the usual period ; one of them, how- 
 evA-, that had taken the mixed solutions, manifested no symp- 
 tom whatever for thirty-five minutes. In some instances, the 
 strychnine symptoms appeared to be not in the least affected by 
 the tobacco ; but in others, they were of a compound nature. 
 Several of the animals vomited. Before performing these ex- 
 periments, it was ascertained that an infusion of twenty grains 
 of tobacco, given alone, would produce serious symptoms ; but 
 in no instance, in six experiments, did it cause death.' 
 
 PosT-MOETEM APPEARANCES. — The most constant appear- 
 ances in death from strychnine are, engorgement of the lungs, 
 and fullness of the blood-vessels of the brain and its membranes, 
 with a fluid condition and dark color of the blood. The heart 
 is generally empty and flaccid. In some instances there is 
 more or less redness of the mucous membrane of the stomach. 
 Congestion of the liver, spleen, and kidneys has also been ob- 
 served. The body usually presents a more or less livid appear- 
 ance. One of the most striking chai-acters in death from this 
 substance, is the rigid condition assumed by the body soon after 
 death. In this state, the joints are fixed, the abdomen hard 
 and tense, legs extended, feet arched, fingers firmly closed, and 
 the head thrown back. In a case recently reported by Dr. 
 Paley, of Peterborough, death took place during a paroxysm, 
 and the tetanic rigidity continued for some time afterwards, the 
 arras being crossed and forcibly bent over the chest, the hands 
 rigidly closed, and the legs perfectly stiff; but in twenty-three 
 hours, there was no unusual rigidity about the limbs. (Brit, 
 and For. Med.-Chir. Eev., Oct., 1860, p. 384.) In all the ani- 
 mals we have killed with this poison, the bodies were flaccid at 
 the time of death, but they soon became rigid. 
 
 In the case reported by Dr. Theinhart, in which death took 
 place in half an hour, the tongue, gums, and lips, as also the 
 
PATHOLOGICAL EFFECTS. 547 
 
 fingers and toes, were of a violet color ; the fingers were closed, 
 and the toes drawn in ; and the whole body was as rigid as a 
 stick of wood, and slightly bent upon itself. In Dr. Blumhardt's 
 case, in which forty grains of strychnine had been taken and 
 death occurred in an hour and a half, twenty-four hours after 
 death the skin was found of a dark color, and the body excess- 
 ively rigid. On opening the vertebral canal, a large quantity 
 of thick fluid blood escaped. The plexuses of the spinal veins 
 and the pia mater were highly congested. The upper part of 
 the spinal marrow was exceedingly soft, but the lower portion 
 hard. The substance of the brain was slightly congested, but 
 the membranes were healthy. The stomach was nearly normal, 
 and contained a slimy mucus. 
 
 In the case of Freet, already mentioned, forty hours after 
 death, the skin was livid, the body rigid, the hands clenched, 
 and the toes drawn upwards. The lower extremities were stiff, 
 but the arms relaxed. The pyloric end of the stomach was 
 somewhat reddened ; and the liver and lungs were gorged with 
 dark liquid blood. The blood throughout the body was of a 
 dark color and fluid. The brain was healthy, but its vessels 
 were nearly destitute of blood. The kidneys and bladder were 
 normal. In Dr. Steiner's case, eighteen hours after death, the 
 body was extremely rigid, and the face, neck, and back, livid. 
 The scalp and membranes of the brain were highly congested 
 with dark liquid blood ; but the substance of the brain and spi- 
 nal marrow presented nothing abnormal. The heart was small, 
 contracted, and contained no blood. The liver, spleen, and 
 pancreas were natural, but the kidneys were highly congested. 
 In the case described by Dr. Keese, six weeks after death, the 
 body was found very rigid, and in a good state of preservation ; 
 the heart was healthy, and contained a considerable quantity of 
 blood. In Dr. Paley's case, in which life was prolonged for 
 about five hours, the only abnoi-mal appearances found in the 
 body twenty-three hours after death, were slight traces of inflam- 
 mation of the lining membranes of the stomach and ilium, and 
 a generally congested state of the thoracic and abdominal or- 
 gans ; the heart was nearly empty, and the blood of a dark 
 color and fluid. 
 
548 STRYCHNINE. 
 
 The following recent case, in which a large quantity of the 
 poison had been taken and proved rapidly fatal, is reported by 
 Dr. Buck (Amer. Med. Times, Oct., 1863, p. 205). Four hours 
 after death : the body was still warm, the face livid, eyes open, 
 pupils natural, jaws firmly closed, lips slightly parted, and frothy 
 matter was escaping from the mouth. The muscles of the neck 
 were relaxed, the arms rigid, and the elbows fixed at right an- 
 gles, with the forearms across the chest ; the fingers were semi- 
 flexed, and when forcibly extended, would fly back — the same 
 was true of the elbow. The legs were rigidly extended, the 
 feet arched, and the great toes were drawn in. In twenty-four 
 hours after death : the neck, back, left arm, right shoulder, and 
 hip-joints were relaxed ; but the other parts of the body were 
 in the same condition as before. On opening the cranium, a 
 large quantity of blood escaped from that cavity. The mem- 
 branes of the brain were congested, but the brain and spinal 
 marrow were healthy. The lungs, lining membrane of the tra- 
 chea, and muscles in front of the neck were congested. The 
 heart was firmly contracted, the ventricles empty, and only a 
 very little blood in the auricles. The mucous membrane of the 
 cardiac portion of the stomach was congested ; all the other or- 
 gans of the abdomen were healthy. A chemical examination 
 of the contents of the stomach, by Dr. A. A. Hayes, of Boston, 
 revealed the presence of a large quantity of strychnine. 
 
 Chemical Propeeties. 
 
 G-ENEEAL Chemical Nature. — In its pure state, strychnine 
 crystallises in the form of colorless, transparent octahedra or in 
 lengthened prisms. When precipitated from complex organic 
 solutions, it often appears in the form of minute granules. As 
 found in the shops, it is usually in the form of a white or dull- 
 white amorphous powder, but it is frequently met with in the 
 form of well-defined crystals. Strychnine has a most intensely 
 bitter taste, but it is destitute of odor. It is not decomposed 
 either by the cold concentrated mineral acids or the caustic 
 alkalies. When gradually heated, it fuses to a brownish liquid, 
 then undergoes decomposition with the evolution of dense white 
 
SOLUBILITY. 549 
 
 fumes ; when heated in the flame of a spirit-lamp, it takes fire 
 and burns with a yellowish smoky flame. It can not be vola- 
 tilised unchanged. 
 
 Strychnine has strong basic properties, and readily unites 
 with acids to form salts, most of which are easily crystallisable. 
 The salts of strychnine, except when containing a colored acid, 
 are colorless ; they have the intensely bitter taste of the pure 
 alkaloid, and are equally poisonous. The neutral sulphate of 
 strychnia crystallises in the form of transparent, colorless, four- 
 sided prisms, which contain seven equivalents of water of crys- 
 tallisation ; on exposure to the air, the crystals become opake, 
 from loss of water of crystallisation. The chloride, or hydro- 
 chlorate, forms slender crystalline needles, which, according to 
 Nicholson and Abel, contain three equivalents of water. The 
 nitrate and acetate appear in the form of beautiful silky needles; 
 the latter of these salts, however, crystallises with difficulty. 
 
 Solubility. 1. In Water. — When excess of pure powdered 
 strychnine is digested at the ordinary temperature for twenty- 
 four hours, with frequent agitation, in distilled water, the solu- 
 tion then filtered, and the filtrate evaporated to dryness at a 
 moderate temperature, it leaves a crystalline residue indicating 
 that one part of the alkaloid had dissolved in 8,333 parts of 
 the liquid. It is usually stated that strychnine dissolves in 
 6,667 parts of water at the ordinary temperature, but the above 
 is the mean result of several very closely accordant experi- 
 ments. Its solubility is much increased by a moderate heat, 
 and much of the excess long remains in solution. 
 
 2. In Ether. — Excess of the finely-powdered alkaloid was 
 digested at the ordinary temperature for twenty-four hours in 
 absolute ether, and the mean of several experiments indicated 
 that one part dissolved in about 1,400 parts of the liquid. It 
 is somewhat more soluble in ordinary ether. One part of the 
 pure alkaloid dissolved in 1,050 parts of commercial ether of 
 specific gravity 0"733. 
 
 3. Chloroform readily takes up one part of the pure alkaloid 
 in eight parts of the menstruum. 
 
 4. Absolute alcohol, when kept in contact at the ordinary 
 temperature with excess of the alkaloid, with frequent agitation, 
 
550 STRYCHNINE. 
 
 for four hours, takes up one part in 207 parts of the liquid. 
 Under similar conditions, one part of the alkaloid will dissolve 
 in about 400 parts of common ivliisTcy. 
 
 5. Amylic-alcohol, when agitated for a few minutes with ex- 
 cess of the alkaloid, at the ordinary temperature, dissolves one 
 part in 122 parts of the menstruum. 
 
 From the foregoing facts, it is obvious that, other things be- 
 ing equal, strychnine is much more completely extracted from its 
 aqueous solution or mixture by chloroform than by ether ; how- 
 ever, the latter liquid will usually answer very well for the 
 detection of the poison. The use of chloroform for the, extrac- 
 tion of the alkaloid from complex organic mixtures has been 
 objected to, on the ground that it acts more solvently than 
 ether upon foreign matters ; but we have not found this objec- 
 tion to hold in ordinary practice. The alkaloid is insoluble in 
 the fixed caustic alkalies, and only very sparingly soluble in 
 ammonia. 
 
 Most of the salts of strychnine are readily soluble in water 
 and in alcohol, they being more freely soluble in the latter liquid 
 than the pure alkaloid. They are also soluble to an appreciable 
 extent in ether. Thus, we find that the acetate dissolves in 
 about 10,000 times its weight of this liquid. The insoluble 
 salts of the alkaloid are readily soluble in the presence of a free 
 acid, even, with very few exceptions, of acetic acid. 
 
 Special Chemical Peopeeties. — Concentrated sulphuric 
 acid dissolves strychnine, as well as its colorless salts, to a col- 
 orless solution, which upon the addition of a crystal of bichro- 
 mate of potash, rapidly passes through a highly characteristic 
 series of colors (see post, coloe test). A crystal of nitrate of 
 potash stirred in the sulphuric acid solution, produces no visible 
 change. Concentrated nitric acid dissolves the alkaloid, and its 
 salts, without change of color, even upon the addition of pro- 
 tochloride of tin : if the strychnine be contaminated with bru- 
 cine, as is frequently the case as met with in commerce, it 
 strikes a red or orange-red color with nitric acid. Hydrochloric 
 acid, also, dissolves the pure alkaloid to a colorless solution. 
 When moistened with a solution of bichromate of potash, strych- 
 nine acquires a beautiful golden-yellow color. 
 
SPECIAL CHEMICAL PROPERTIES. 551 
 
 Pure solutions of strychnine, and of its salts, are colorless 
 and odorless, and have the bitter taste of the pure alkaloid. 
 Upon slow evaporation, they leave the poison in its crystalline 
 form. An alcoholic solution of the free alkaloid quickly restores 
 the blue color of reddened litmus-paper. This reaction is also 
 perceptible in a saturated aqueous solution of the" alkaloid. 
 
 The taste of strychnine, under certain conditions, is one of 
 its most characteristic properties, and it may be recognised even 
 in highly diluted solutions. Thus, a single grain of a 50,000th 
 pure aqueous solution of the alkaloid — equal to the 50,000th of 
 a grain of strychnine — has a quite perceptible bitter taste. A 
 similar quantity of a 100,000th solution has a perceptible taste, 
 but this can hardly be said to be bitter. It has been asserted 
 that even much less quantities of the poison than the last- 
 mentioned, may thus be indicated, but in our own personal 
 experience, we have not met with a person whose sense of taste 
 extended beyond the quantities just stated. Moreover, the taste 
 of these minute quantities is readily disguised by the presence 
 of foreign substances. In a drop of a 10,000th solution, the 
 taste is usually very decided and well-marked, even in the 
 presence of a very notable quantity of foreign matter. 
 
 That the taste is equally or even more delicate for the de- 
 tection of strychnine than any of the known chemical methods, 
 as has been asserted by some writers, is certainly erroneous. 
 Nevertheless, this is one of the best corroborative tests yet 
 known, and its application should never be omitted. Should it 
 fail, under ordinary conditions, it would follow that at most 
 there was only a very minute quantity of the alkaloid present. 
 On the other hand, it must be remembered that other substances, 
 such as quinine, quassia, colocynth, picrotoxin, and morphine, 
 possess a somewhat similar bitterness. 
 
 In the following investigations in regard to the action of 
 reagents upon solutions of strychnine, the alkaloid was em- 
 ployed in the form of a salt, but chiefly as the acetate. The 
 fractions employed indicate the fractional part of a grain of the 
 anhydrous alkaloid in solution in one grain of pure water. The 
 results, unless otherwise indicated, refer to the behavior of one 
 grain of the solution. 
 
552 STRYCHNINE. 
 
 1. Potash and Ammonia. 
 
 The fixed caustic alkalies and ammonia throw down from 
 somewhat concentrated solutions of salts of strychnine a white 
 amorphous precipitate of the pure alkaloid, which in a little 
 time assumes the crystalline form. From more dilute solutions, 
 the precipitate does not appear tmtil after a little time, and it 
 then separates in its crystalline state. Solutions still more dilute, 
 may entirely fail to yield a precipitate. The precipitate is 
 insoluble in potash and soda, and only sparingly soluble in am- 
 monia, but it immediately disappears upon the addition of almost 
 any of the diluted acids. When a somewhat strong solution of 
 a salt of the alkaloid is exposed to the vapor of ammonia, it 
 immediately becomes covered with a white film, and in a little 
 time changes to a nearly solid mass of crystals. 
 
 1. Yoo grain of strychnine, in one grain of water, yields, with 
 
 either of the reagents, an immediate, copious precipitate, 
 which very soon becomes converted into a mass of crys- 
 tals of one or more of the forms illustrated in Plate X, 
 fig. 1. If after the addition of the reagent, the mixture 
 be allowed to remain very quiet, it yields very beautiful 
 compound stellate crystalline groups of the form illustrated 
 in the lower part of the figure ; these forms are especially 
 apt to be produced if the alkaloid contains a little brucine. 
 
 2. t:oWo grain : after a few moments, crystalline needles and 
 
 groups begin to appear, and in a very little time, there is 
 a quite good deposit. If upon the addition of the reagent, 
 the mixture be stirred with a glass rod, it almost immedi- 
 ately yields a very good, amorphous precipitate, which 
 very soon changes into short crystalline needles. 
 
 3- 2","5Vo grain : after a few minutes, a very satisfactory crys- 
 talline precipitate has formed. If the mixture be stirred, 
 the formation of the precipitate is much facilitated, and it 
 is more abundant. 
 
 4. 5,0^0 grain, when treated with a very small quantity of 
 reagent, yields, after some minutes, especially if the mix- 
 ture be stirred, a very satisfactory crystalline precipitate. 
 
COLOR TEST. 553 
 
 The alhaline carionates produce, in solutions of salts of 
 strychnine, reactions similar to those of the free alkalies. 
 
 It need hardly be remarked that the production of a white 
 crystalline precipitate by either of the foregoing reagents, is not 
 in itself positive proof of the presence of strychnine. The crys- 
 talline forms of this alkaloid, however, are somewhat peculiar. 
 The true nature of the precipitate, even when present only in 
 the most minute quantity, may be readily established by means 
 of the test just to be mentioned. 
 
 2. Color Test. 
 
 This test, which is the most characteristic, and at the same 
 time, when applied to the pure alkaloid, one of the most deli- 
 cate yet known for the detection of strychnine, is based upon 
 the development of a series of colors when a sulphuric acid 
 solution of the alkaloid is treated with certain oxidising agents. 
 Marchand, in 1843, was the first to point out that when strych- 
 nine was dissolved in sulphuric acid containing a little nitric 
 acid, and the mixture stirred with a small quantity of peroxide 
 of lead, the liquid immediately acquires a deep blue color, which 
 rapidly changes to purple or violet, then gradually to red, which 
 very slowly fades. 
 
 This development of colors is due to the action of the nas- 
 cent oxygen, evolved hy the acids and lead compound, upon 
 the strychnine. Any combination that will eliminate oxygen 
 will produce these results, providing the substance from which 
 it is evolved or some substance evolved along with it from 
 the oxidising agent, does not interfere with the action of the 
 nascent gas. Mack, in 1846, proposed the use of sulphuric 
 acid and binoxide of manganese, and about the same time, 
 Otto suggested this acid and bichromate of potash. More re- 
 cently, it has been proposed to substitute for these metallic 
 combinations various other substances, such as ferricyanide of 
 potassium, chromic acid, the alkaline iodates, and permanga- 
 nate of potash. Most of these substances were advanced un- 
 der the claim, either, that they were more delicate in their 
 reaction, or else less subject to interferences, than those that 
 
554 STRYCHNINE. 
 
 had previously been proposed ; but a careful and impartial 
 comparative examination stows that at most there is but little 
 difference between them in regard to delicacy of reaction, and 
 that they are all about equally affected by the presence of cer- 
 tain foreign substances. Of these different oxidising substances, 
 we prefer, for this purpose, the bichromate of potash ; this salt 
 is readily obtained in its pure crystalline state. For the detec- 
 tion of very minute traces of the alkaloid, it is better to have 
 the color-developing agent in the form of a minute crystal than 
 in the state of powder. Binoxide of manganese and peroxide 
 of lead dissolve in sulphuric acid without change of color, but 
 bichromate of potash and ferricyanide of potassium impart a 
 yellowish, while permanganate of potash gives a greenish color 
 to the acid. These colors, however, at most undergo but slow 
 change, and could not possibly be confounded with the series of 
 colors produced by strychnine. 
 
 To apply this test, a small quantity of the alkaloid, or any 
 of its salts, in the solid state, is placed on a piece of white por- 
 celain or in a watch-glass over white paper, and dissolved in a 
 drop of pure concentrated sulphuric acid, in which, if pure, it 
 dissolves without change of color. A small crystal of bichro- 
 mate of potash, or a small portion of either of the other color- 
 developing agents, is now added to the solution and, when 
 moistened with the acid, slowly moved around in the liquid 
 by means of a pointed glass rod, when either immediately or 
 in a few moments, the peculiar succession of colors, beginning 
 with a beautiful blue, will manifest itself. The blue color 
 quickly passes into purple, this into violet, and this more slowly 
 into red, which very slowly fades. The liquid ultimately ac- 
 quires either a yellow or greenish color, or becomes entirely 
 colorless ; but these results are altogether independent of the 
 action of the strychnine. An important point to be observed, 
 when applying the test to a suspected substance, is the non- 
 coloration by the acid alone. 
 
 As the intensity and duration of the colors thus produced, 
 depend very much upon the amount of strychnine operated upon, 
 as well as the relative quantities of acid and color-developing 
 agent employed, and the physical state of the latter, it is 
 
COLOR TEST: DELICACY. 555 
 
 impossible to give any description that will fully meet every 
 case ; yet whenever developed, they are so peculiar as to be 
 readily recognised, even when only the merest trace of the poison 
 is present. With a very minute quantity of the alkaloid, the 
 blue color may continue only for a moment, or it may even be 
 entirely absent, the mixture developing at first a purple or violet 
 color, quickly passing to red. To obtain the best results from 
 these minute quantities, the acid should be very concentrated 
 and added in only very minute quantity, and only a very small 
 fragment of the oxidising agent employed. 
 
 Another method of applying the test, is to place a small 
 drop of sulphuric acid by the side of the strychnine, and then 
 stir a very small crystal of bichromate of potash in the acid 
 until it imparts a slight yellow color to the liquid, when the 
 moistened crystal is dragged over the strychnine, by means of 
 a pointed glass rod ; or, the colored acid may be allowed to flow 
 over the alkaloid, by gently inclining the dish. For the recog- 
 nition of minute quantities of the poison, this method is even 
 more delicate than that just described. Since, however, as we 
 shall see hereafter, in examining a suspected deposit, it is fre- 
 quently important to know the action of the acid alone, this 
 method is not always applicable. The test may also be applied 
 to solutions of strychnine, by treating a drop of the liquid with 
 a drop or two of concentrated sulphuric acid, and stirring in 
 the cooled mixture a small quantity of the color-developing 
 agent. This method, however, only applies to somewhat strong 
 solutions of the alkaloid, and, even under these circumstances, 
 the results are by no means as uniform as when the poison is 
 in its solid state. 
 
 Delicacy of the test. — In the following examinations in regard 
 to the Emit of the reaction of this test, the quantities of strych- 
 nine were obtained by evaporating one grain of a corresponding 
 solution of a salt of the alkaloid to dryness spontaneously. This 
 method of evaporation is much preferable to that on a water- 
 bath, since it much more frequently leaves the poison in its 
 crystalline state, which is better adapted to the application of 
 the test than the amorphous form. The results refer more 
 especially to those produced by the bichromate of potash as the 
 
556 STRYCHNINE. 
 
 oxidising agent, and are based on yery frequently repeated 
 
 experiments. 
 
 !• To~o grain of strychnine, in the form of acetate, when ob- 
 tained in the manner just described, forms a very fine 
 crystalline deposit, which, when examined by the test, 
 yields a magnificent display of colors. 
 
 2. T7o"oo grain, leaves a quite good crystalline residue, which 
 
 yields, with the test, results very similar to those under 1. 
 The same quantity of the alkaloid in solution in one grain 
 of water, yields very satisfactory results. 
 
 3. 10,000 grain: the residue consists of a number of well-defined 
 
 crystals, which when treated with the test, yield a per- 
 fectly satisfactory succession of colors. The results ob- 
 tained from this quantity of the alkaloid, when free from 
 foreign matter and manipulated with care, are just as sat- 
 isfactory, so far as the evidence of the presence of the 
 alkaloid is concerned, as those obtained from any larger 
 quantity, the only difference being in the duration of the 
 difi'erent colors. 
 
 4. 5 0,0 grain : the residue usually contains a number of dis- 
 
 tinct microscopic crystals ; when the deposit is moistened 
 with a trace of the acid, and treated with a mere frag- 
 ment of the potash salt, it yields very satisfactory evidence 
 of the presence of the poison. 
 5- 10 0% grain : if the residue is not much distributed, it usu- 
 ally contains some few minute crystals, and when treated 
 as under 4, yields a very distinct coloration. For the 
 success of this reaction, it is essential that the residue be 
 deposited within a narrow compass, and that the merest 
 trace of the acid and color-developing agent be employed. 
 Under these circumstances, it will yield quite satisfactory 
 results. The acid is best applied, by moistening the end 
 of a small glass rod with the liquid and then drawing it 
 over the deposit. 
 When collected at one point, and perfectly free from foreign 
 matter, even a much smaller quantity of the alkaloid than the 
 last-mentioned, will yield, under the action of the test, a very 
 distinct purplish or violet coloration, especially if the fragment 
 
COLOR TEST: DELICACY. 557 
 
 of bichromate of potash be first moistened with the acid, and 
 then brought in contact with the poison. The residues obtained 
 from solutions of the poison may be collected within a small 
 space, by allowing the liquid to evaporate in a very concave 
 watch-glass ; or, better still, as first advised by Messrs. Rodgers 
 and Girdwood, by collecting the solution in a pipette provided 
 with a small capillary point, and from this applying a minute 
 drop of the liquid to a warmed surface, and repeating the 
 operation, as the fluid evaporates, until a sufficient deposit is 
 obtained. 
 
 The limit of this test, particularly when bichromate of pot- 
 ash is used as the color-developing agent, has been the subject 
 of much misapprehension. Thus, under these circumstances, 
 in the hands of some experimentalists, the test failed with quan- 
 tities of the alkaloid only a little less than the 2,000th or 
 3,000th part of a grain. But that these failures were not due 
 to any want of delicacy on the part of the method itself, is 
 quite apparent from the foregoing experiments. So, also, it 
 has been claimed, that some of the other oxidising agents are 
 more delicate in this respect than the bichromate of potash. 
 Since, however, this salt, when properly applied, will produce a 
 distinct coloration with the least quantity of the alkaloid visible 
 to the naked eye, and under the microscope, with about the 
 least crystal visible by this instrument, it is obvious that it 
 reaches the possible practical limit of any of the color-devel- 
 oping agents. 
 
 It is not thus intended to imply that in regard to delicacy, 
 this method is superior to any yet proposed, but only that it is 
 not inferior : similar results may be obtained at least from the 
 employment of ferricyanide of potassium, as first proposed by 
 Dr. E. Davy, and the permanganate of potash, as advised by 
 Dr. Guy, and also from the binoxide of manganese. It has 
 been stated by some observers, that the colors produced by 
 powdered binoxide of manganese and of peroxide of lead, are 
 much more intense than those produced by the bichromate 
 of potash ; but this is only true of given quantities of the 
 alkaloid, and depends upon the physical state of these me- 
 tallic compounds, similar results being equally produced by 
 
558 STRYCHNINE. 
 
 finely-powdered bichromate of potash or of ferricyanide of potas- 
 sium, as also by powdered permanganate of potash. 
 
 Interferences. — Although this test will serve to reveal the 
 nature of the least visible quantity of strychnine when in its 
 pure state ; yet, the presence of certain foreign substances may 
 cause it to entirely fail, even when comparatively large quanti- 
 ties of the poison are present. In this respect, the action of 
 the different color-developing agents is about equally affected. 
 Brieger, in 1850, first announced that the reaction was more 
 or less interfered with by the presence of morphine and its salts, 
 quinine, and sugar (Chem. Graz., vol. viii, p. 408) ; and since 
 then, it has been asserted that tartar emetic, nitric acid and 
 nitrates, common salt, corrosive sublimate, and various other 
 substances, had a similar property. Many of these substances, 
 however, even when present in relatively large quantity, exer- 
 cise but little influence over the test ; but others of them may 
 entirely prevent its ordinary reaction. 
 
 Morphine belongs to the latter class of these substances. 
 The influence of this substance is determined, both by the rela- 
 tive and absolute quantity present. Thus, when 100th part of 
 a grain each of strychnine and morphine, or of their salts, are 
 thoroughly mixed, by evaporating their mixed solutions to dry- 
 ness, they yield, under the action of the test, little or no indi- 
 cation of the presence of the strychnine ; whilst, if a mixture 
 of 1,000th of a grain each be examined, it yields very satis- 
 factory evidence of the presence of that alkaloid. In other 
 words, a very minute quantity of a mixture of equal parts of 
 the alkaloids, will yield much better results than will be fur- 
 nished by a larger quantity of the mixture. When, however, 
 the relative quantity of morphine exceeds several times that of 
 the strychnine, the reaction of the test may be entirely masked, 
 even with very small quantities of the mixture. 
 
 When these alkaloids exist in the same solution, they may 
 be separated by rendering the mixture alkaline and agitating it 
 with pure chloroform, in which the strychnine is very freely 
 soluble, whilst the morphine is almost absolutely insoluble, espe- 
 cially in the presence of a free alkali. It is therefore obvious, 
 that when strychnine has been extracted from organic mixtures 
 
COLOR TEST: INTERFERENCES. 559 
 
 by means of chloroform, in the manner to be pointed out here- 
 after, this interference on the part of morphine, to the color- 
 test, does not exist. Experiments show that this is even true 
 of the extract obtained from a strongly alkaline 100th solution 
 of morphine containing only the 10,000th of its weight of 
 strychnine, and even when several volumes of chloroform are 
 employed for the extraction. These facts are equally appli- 
 cable when pure ether is employed as the extracting agent, 
 especially if after the addition of the mineral alkali, the mix- 
 ture be allowed to stand some few minutes, before being agi- 
 tated with the liquid. 
 
 For the separation of these alkaloids, it has been proposed 
 to precipitate the strychnine by a solution of bichromate of pot- 
 ash. But, as this reagent also produces precipitates in strong 
 solutions of salts of morphine, especially after standing some 
 time, and, also, as the chromate of strychnia is but little less 
 soluble in water than the pure alkaloid, it is obvious that we 
 might have a mixture of these substances from which the pre- 
 cipitate would consist largely, or even entirely, of chromate of 
 morphia ; and, moreover, that even under the most favorable 
 circumstances, a given quantity of the strychnine would remain 
 in solution, and thus entirely escape detection. In the presence 
 of a free alkali, the bichromate of potash is converted, in part 
 at least, into the protochromate, which is a more delicate pre- 
 cipitant of morphine than of strychnine. 
 
 Nitrates, such as the nitrate of potash, interfere with the 
 normal reaction of the test to nearly or about the same extent 
 as morphine. This interference, like that of morphine, applies 
 equally to the different color-developing agents. In regard to 
 the influence of tartar emetic, our own observations fully confirm 
 those of Mr. Hagen (Chem. Gaz., 1857, p. 397), namely, that 
 this substance may be present even in very large excess without 
 exerting any very marked influence ; yet, when the mixture 
 contains twenty or thirty parts of the compound, it may entirely 
 disguise the ordinary reaction of the test. These observations 
 are equally applicable in regard to the modifying influence of 
 sugar. Since the nitrates, tartar emetic, and sugar are insolu- 
 ble in chloroform, neither of these substances could be present 
 
560 STRYCHNINE. 
 
 with strychnine when the alkaloid is extracted from organic 
 mixtures by that liquid. 
 
 A much more serious interference, than any yet mentioned, 
 to this test, is the presence of certain undefined organic sub- 
 stances frequently extracted from complex mixtures by chloro- 
 form and by ether. It is no unusual occurrence to thus obtain 
 extracts, which fail to reveal the presence of strychnine, even 
 when comparatively large quantities of the alkaloid are pur- 
 posely added. In fact, this is so frequently the case when only 
 a very minute trace of the poison is present, that should a sus- 
 pected extract fail to indicate the presence of the poison, before 
 concluding that the latter is entirely absent, it is always best 
 to add, to a separate portion of the extract, a very minute 
 quantity of the pure alkaloid and determine whether the failure 
 might not be due to this cause. The best method for separating 
 substances of this kind, is to dissolve the chloroform residue in 
 a small quantity of acidulated water, treat the solution with 
 slight excess of an alkali, and again extract with chloroform ; 
 sometimes it may be necessary to repeat all these operations. 
 
 Fallacies. — It has been objected to this test, that under its 
 action various other substances, as aniline, curarine, cod-liver 
 oil, pyroxanthine, papaverine, narceine, veratrine, and solanine, 
 yield colors somewhat similar or even identical with those pro- 
 duced from strychnine. When, however, the test is properly 
 applied and observed, these objections have little or no practical 
 force. Thus, all these substances, except aniline, unlike strych- 
 nine, yield their colors or at least are colored, by sulphuric acid 
 alone; and, furthermore, none of them, except curarine and 
 cod-liver oil, even by the conjoined action of the acid and 
 color-developing agent, yields, like strychnine, a series or quick 
 succession of colors. Although these objections may be thus 
 summarily answered ; yet it is only proper that the chemical 
 nature of some at least of these fallacious substances be consid- 
 ered somewhat in detail. 
 
 Aniline, in its pure state, is a colorless liquid, having a 
 rather pleasant odor, and a sharp acrid taste : it is obtained 
 from coal-tar, and by the action of potash upon indigo; it may 
 also be obtained by various other methods. When treated with 
 
COLOR TEST: FALLACIES. 561 
 
 concentrated sulphuric acid, it undergoes no change of color, 
 but it throws down, if present in notable quantity, a white pre- 
 cipitate of the sulphate of aniline. The salts of this base are 
 colorless, nearly tasteless, and, for the most part, readily crys- 
 tallisable. The sulphate has recently been employed as a ther- 
 apeutic agent. Pure aniline is readily soluble in chloroform, 
 but its salts are almost wholly insoluble in that liquid. 
 
 When the salts of aniline are treated with concentrated sul- 
 phuric acid, they, like the salts of strychnine, yield no colora- 
 tion ; but, when a crystal of bichromate of potash, or a small 
 portion of any of the other oxidising agents, is stirred in the 
 acid mixture, the latter slowly acquires a yellowish or greenish 
 tint, then presents bluish streaks, and after a little time, assumes 
 a beautiful deep blue color, which undergoes but little change 
 for half an hour or even much longer, but it finally becomes 
 nearly or entirely black. From this description, it is obvious 
 that the reaction of this substance bears but little similarity to 
 that of strychnine, about the only resemblance being in the 
 production of a deep blue color. But in the case of strychnine, 
 as remarked by Dr. Guy, this color is the first produced, and 
 is developed either immediately or at most within a few mo- 
 ments, and is quickly followed by other characteristic colors, it 
 being itself exceedingly transient ; whereas, in the case of ani- 
 line, this color is but slowly developed, is preceded by other 
 colors, and when once established is exceedingly persistent, and 
 ultimately becomes black. In this connection, it may be stated 
 that Dr. Letheby reports (Chem. News, vol. v, p. 71) two cases 
 of accidental poisoning by nitro-benzole, in which he found that 
 it was changed in the animal body into aniline. 
 
 Curarine is the name applied to the active principle, or /LL^-^ 'ff 
 alkaloid, found in Woorara, or Curara, the substance employed, ^:^u•'l <^./i 
 by the Indians of South America for poisoning their arrows. fH^'^t-Tx!^, 
 Much doubt exists as to the true nature of woorara. According Oic^^f 
 to Water ton, it is prepared from several different plants, two / 
 species of poisonous ants, and the fangs of certain snakes; 
 while Schomburgk states that it consists alone of vegetable mat- 
 ter, and chiefly of an extract of the bark of the stryclmos tox- 
 ifera, a tree found native in Guiana. Various other statements 
 
 36 
 
562 STRYCHNINE. 
 
 have been made in regard to its composition. That there are 
 at least several varieties of this substance current among the 
 different tribes of Indians, seems to be fully established by the 
 recent investigations of Drs. Hammond and Mitchell (Amer. 
 Jour. Med. Sci., July, 1859, pp. 13—61); and it is even proba- 
 ble that each tribe has its own method for preparing the poison. 
 It was formerly believed that the poisonous properties of woo- 
 rara were due to the presence of strychnine, but this alkaloid 
 has not been found in any of the specimens yet examined. In 
 fact, the physiological effects of this substance are the very 
 opposite to those of strychnine, and it has even been advised 
 as an antidote in poisoning by that alkaloid. 
 
 Woorara is usually described as a hard, black or nearly 
 black, brittle, resin-like solid, of an intensely bitter taste ; in 
 the state of powder, it has a dark brown color. It is, for the 
 most part, readily soluble in water and in alcohol, but only very 
 slightly acted upon by ether and chloroform, even in the pres- 
 ence of a free alkali. The statements in regard to the chemical 
 properties of this substance have been somewhat conflicting. 
 The active principle, or curarine, as obtained by MM. Roulin 
 and Boussingault, who were the first to isolate the alkaloid, was 
 in the form of a transparent solid, having a pale-yellow color, 
 and an exceedingly bitter taste. It, as well as all its salts, was 
 uncrystallisable. According to Bernard, curarine dissolves in 
 concentrated sulphuric acid with the production of a beautiful 
 carmine color; and Pelikan states that under the combined 
 action of this acid and a color-developing agent, as bichromate 
 of potash or a current of electricity, it yields a brilliant red 
 color. It would appear that quite recently M. Preyer obtained 
 curarine, as well as its soluble salts, in the crystalline form. 
 (Chem. News, London, July, 1865, p. 10.) According to this 
 observer, the pure alkaloid yields with concentrated sulphuric 
 acid a magnificent and lasting blue color ; while with this acid 
 and bichromate of potash, it yields much the same series of 
 colors as strychnine. With strong nitric acid, it yields a pur- 
 ple coloration. 
 
 A specimen of ordinary woorara, kindly furnished us in lib- 
 eral quantity by Dr. S. Wier Mitchell, of Philadelphia, has the 
 
COLOR TEST: FALLACIES. 563 
 
 following properties. Its physical properties are the same as 
 those just described. When treated, in its crude state, with 
 concentrated sulphuric acid, it slowly yields, without entirely 
 dissolving, a reddish-brown solution, which when stirred with a 
 small portion of bichromate of potash, or any other oxidising 
 agent, gives a series of colors very similar to that produced 
 from a very impure mixture of strychnine. Concentrated nitric 
 acid dissolves it, with evolution of binoxide of nitrogen, to a 
 deep reddish-brown solution. It is for the most part readily 
 soluble in water, especially upon the application of heat ; the 
 insoluble portion consists apparently of vegetable fragments. 
 The filtered aqueous solution has a deep brownish color, an 
 intensely bitter taste, and a just perceptible acid reaction. It 
 is about equally soluble in strong alcohol. The concentrated 
 aqueous solution yields with a solution of bichromate of potash 
 a yellow amorphous precipitate, which when washed and treated 
 with a small quantity of concentrated sulphuric acid, yields a 
 series of colors not to be distinguished from that produced 
 under similar circumstances from the chromate of strychnia. 
 This precipitate, however, differs from the strychnia compound, 
 in being uncrystallisable, and readily soluble in water. 
 
 When a strong aqueous solution of several grains of an alco- 
 holic extract of the crude poison, is rendered strongly alkaline 
 with potash and agitated with chloroform, this liquid remaias 
 colorless, and leaves upon spontaneous evaporation, a slight, 
 yellowish, gum-like residue, having an intensely bitter taste. 
 When a minute portion of this residue is touched with a drop 
 of sulphuric acid, it acquires a red color and very soon dis- 
 solves to a solution of the same hue ; if a small crystal of 
 bichromate of potash be now stirred in the solution, it produces 
 a series of colors the perfect counterpart of that from strych- 
 nine, with perhaps the exception that the blue and purple colors 
 are somewhat more persistent than those from an equal quantity 
 of the latter substance. Under the action of nitric acid, the 
 chloroform residue assumes a red color, and dissolves to a red- 
 dish solution ; this color is discharged by heat, and the cooled 
 liquid remains unchanged on the addition of protochloride of 
 tin. The alkaline solution from which the chloroform extract 
 
564 STRYCHNINE. 
 
 was obtained, has an intensely bitter taste, and yields with a 
 solution of bichromate of potash a rather copious amorphous 
 precipitate, having the same properties as the precipitate from 
 an aqueous solution of the crude poison. When a small quan- 
 tity of the alkaline solution is treated with sulphuric acid, it 
 acquires a beautiful purple color, which on the addition of a 
 crystal of bichromate of potash is changed to a deep blue, fol- 
 lowed by purple and the other peculiar colors. The alkaline 
 solution also yields other reactions indicating that but little of 
 the active principle had been removed by the chloroform. 
 Various efforts were made to obtain this principle, and some 
 of its compounds, in the crystalline state, but in all cases with- 
 out success. 
 
 It thus appears that this sample of woorara contains a prin- 
 ciple having certain chemical properties in common with strych- 
 nine. Thus, like strychnine, it has an intensely bitter taste ; 
 yields under the combined action of sulphuric acid and an oxid- 
 ising agent a particular series of colors ; and its bichromate of 
 potash precipitate yields, with this acid alone, similar results. 
 But these are about the only respects in which it resembles that 
 alkaloid. Among the differences existing between this principle, 
 at least in the sample under consideration, and strychnine, may 
 be mentioned the following : it and all its compounds are un- 
 crystallisable ; it is colored by sulphuric acid alone ; its bichro- 
 mate of potash precipitate is rather readily soluble in water and 
 is amorphous ; it is almost wholly insoluble in chloroform, and 
 readily soluble in potash ; and its solutions are not precipitated 
 by the caustic alkalies. In addition to these facts, the extreme 
 rarity of this substance in civilized communities, would deprive 
 it of any practical force as a source of fallacy in medico-legal 
 investigations for strychnine. 
 
 It may here be added, that three grains of the above woo- 
 rara were administered in solution to a young cat without pro- 
 ducing any appreciable effect whatever; although the animal 
 was closely watched for twelve hours. But, a very small quan- 
 tity of the paste introduced under the skin of the inside of 
 the thigh of a similar animal, produced almost immediate stu- 
 por, and in eight minutes complete prostration ; this condition 
 
COLOR TEST: FALLACIES. 565 
 
 continued, with occasional convulsive movements, for some 
 hours, after which the animal completely recovered. 
 
 Cod-liver oil has also been mentioned as a source of fallacy. 
 This substance when treated with sulphuric acid alone, yields a 
 series of colors which might be confounded with that produced 
 from strychnine by the combined action of this acid and an 
 oxidising agent. But as strychnine yields no coloration with 
 sulphuric acid alone, it is obvious that when the acid is applied 
 first and its action observed, all grounds for objection, so far as 
 this oil is concerned, are at once removed. Moreover, the 
 physical state of cod-liver oil would at once distinguish it from 
 strychnine, or any of its salts, in the solid state. 
 
 The' objections in regard to the other substances heretofore 
 mentioned, have already been answered, namely, that they are 
 colored by sulphuric acid alone, and under no circumstance do 
 they yield a quick succession of colors. Thus, pyroxanthine, 
 which has a bright red color, yields with the acid, a blue solu- 
 tion ; papaverine, a purple ; narceine, a reddish-yellow or brown- 
 ish color ; veratrine, a yellow, slowly becoming crimson ; and 
 solanine, an orange-brown mixture. It may be remarked, that 
 the exact tint of color produced by the acid with at least some 
 of these substances, is more or less modified by the quantity of 
 material employed. 
 
 In addition to the substances now considered, there are a 
 number of alkaloids and other organic proximate principles, 
 which when treated either with sulphuric acid alone or with 
 this acid and an oxidising agent, give rise to more or less col- 
 oration. The action of this test with a number of these sub- 
 stances, was first examined by M. Eboli (Chem. Gazette, 1856, 
 p. 251); then by Dr. T. E. Jenkins, of Louisville, Ky., who 
 extended the investigation to about fifty of these principles 
 (Semi-Monthly Med. News, April, 1859, p. 214); and still more 
 recently, by Dr. Guy, of London (Chemical News, Aug., 1861, 
 p. 113), who added some sixteen substances to those examined 
 by Dr. Jenkins. But of aU the substances thus examined, ex- 
 clusive of some already mentioned, none gave results resembling 
 the reactions of strychnine, even to the extent of those already 
 considered. 
 
566 STRYCHNINE. 
 
 Galvanic Test. — This in principle is the same as the pre- 
 ceding method, only that the oxygen is rendered nascent by a 
 current of voltaic electricity, instead of being evolved from a 
 metallic oxide, by means of sulphuric acid. It may be applied, 
 according to Dr. Letheby, who, we believe, first advised the 
 process (London Lancet, June 28, 1856, p. 708), by placing a 
 drop of the strychnine solution in a cup-shaped depression made 
 in a piece of platinum-foil, evaporating the liquid at a low tem- 
 perature, and moistening the residue with a small drop of con- 
 centrated sulphuric acid. The foil is then connected with the 
 platinum pole of a single cell of Grove's or Smee's battery, and 
 the acid liquid touched with the platinum terminal of the nega- 
 tive pole. In a moment the violet coloration manifests itself in 
 great intensity. 
 
 In regard to the delicacy of this method, it is much the 
 same as that of the test as ordinarily applied. Thus, according 
 to our own experiments, the 10,000th part of a grain of strych- 
 nine, yields a fine display of colors; and the 100,000th of a 
 grain, a distinct reaction. Since, however, this process is not 
 so readily applied as the ordinary method and, according to the 
 observations of Dr. J. J. Reese (Amer. Jour. Med. Sci., Oct., 
 1861, p. 417), as well as our own, is about equally open to the 
 interferences and so-called fallacies that hold against the ordi- 
 nary method, it seems to possess no advantage over the latter. 
 In fact, as observed by Dr. Reese, it is less satisfactory, than 
 the usual method, for the recognition of very minute traces 
 of the poison. 
 
 3. Sulphocyanide of Potassium. 
 
 This reagent throws down from solutions of salts of strych- 
 nine, when not too dilute, a white crystalline precipitate of the 
 sulphocyanide of strychnine, which, according to Nicholson and 
 Abel, has the constitution C42H23N2O4, CyS2. The precipitate is 
 insoluble in excess of the precipitant, and but sparingly soluble 
 in diluted acetic and hydrochloric acids. 
 
 1. xo'o' grain of strychnine, in one grain of water, yields an 
 immediate crystalline deposit, and in a few moments the 
 
BICHROMATE OF POTASH TEST. 567 
 
 mixture becomes a nearly solid mass of crystals, of the 
 forms shown in Plate X, fig. 2. 
 
 2- Tro"oo grain : by stirring the mixture, in a very little time it 
 throws down crystals, and soon, there is a very satisfac- 
 tory deposit. 
 
 3. 57io"oo grain, yields, especially if the mixture be stirred, after 
 
 some minutes, a satisfactory deposit of crystalline needles. 
 
 Sulphocyanide of potassium also produces white crystalline 
 
 precipitates in solutions of several of the other alkaloids. 
 
 4. Iodide of Potassium. 
 
 Somewhat strong solutions of salts of strychnine, yield with 
 iodide of potassium, a white crystalline precipitate, which is 
 insoluble in excess of the precipitant and in the free alkalies, 
 and only slowly soluble in large excess of acetic, nitric, and 
 hydrochloric acids. The formation of the precipitate is much 
 facilitated by stirring the mixture with a glass rod. 
 1 • Too" grain of strychnine : in a few moments, the mixture be- 
 comes a nearly solid mass of crystals, of the same forms as 
 those produced by the preceding reagent (Plate X, fig. 2). 
 
 2. 1,000 grain : after a few minutes, especially if the mixture be 
 
 stirred, a quite good deposit of stellate groups of crystals. 
 
 3. sTo^-g grain : after several minutes, there is a quite satisfac- 
 
 tory crystalline deposit. 
 The precipitates produced by this and the preceding reagent, 
 can not readily be confirmed by the color test. 
 
 5. JBichromate of Potash. 
 
 This reagent produces in solutions of salts of strychnine a 
 bright-yellow precipitate of the chromate of strychnia, which 
 almost immediately becomes crystalline. The precipitate is 
 insoluble in excess of the precipitant, and in acetic acid, and 
 only very sparingly soluble in diluted nitric acid, but readily 
 soluble in the concentrated acid ; its color is changed to pale 
 yellow by potash, and, if from dilute solutions, the deposit is 
 slowly dissolved. From dilute solutions of the alkaloid, the 
 
568 STRYCHNINE. 
 
 precipitate does not appear until after a little time, and it then 
 separates in the crystalline form ; under these circumstances, 
 its formation is much facilitated by stirring the mixture with a 
 glass rod. 
 
 1. Yoo^ grain of strychnine, yields a very copious precipitate, 
 
 which in a very Kttle time becomes a dense mass of bush- 
 like crystals. 
 
 2. "Too^ grain : an immediate deposit, and very soon, a copi- 
 
 ous, crystalline precipitate. If after the addition of the 
 reagent, the mixture be allowed to remain quiet, the pre- 
 cipitate, after a little time, forms rfiost beautiful dendroidal 
 groups of crystals, Plate X, fig. 3. 
 
 3. 1,000 grain, yields no immediate precipitate, but very soon 
 
 crystals appear, and in a few minutes, there is a quite 
 
 good deposit. If the mixture be stirred, it yields almost 
 
 immediately, a very good crystalline precipitate. 
 
 ^' STsS'o grain : on stirring the mixture, in a few moments, it 
 
 yields streaks of granules along the path of the glass rod, 
 
 and soon a quite good deposit of octahedral and bush-like 
 
 crystals, Plate X, fig. 4. 
 
 5. 5",'Wo grain : if the mixture be stirred, it yields, after some 
 
 minutes, a very satisfactory deposit of small octahedral 
 
 crystals and plates. 
 
 6- 10,0 'Q grain : when treated with a small quantity of reagent 
 
 and the mixture stirred, it yields, after several minutes, 
 
 small granules ; after about twenty minutes, there is a very 
 
 satisfactory microscopic crystalline deposit of long plates, 
 
 granules, and small octahedral crystals. 
 
 If the supernatant liquid of any of the above deposits be 
 
 decanted, the crystals dried, and then touched with a small 
 
 drop of concentrated sulphuric acid, they immediately assume 
 
 a magnificent blue color, quickly changing to purple or violet, 
 
 and dissolve to a purple or violet solution, which, passing 
 
 through various shades of color, becomes red, then slowly fades. 
 
 In other words, these crystals may be confirmed by the color 
 
 test by the simple addition of sulphuric acid. The precipitate 
 
 obtained from the 10,000th of a grain of strychnine, in solution 
 
 in one grain of water, will, in this manner, yield a magnificent 
 
BICHROMATE OF POTASH TEST. 569 
 
 display of colors ; and even the least microscopic crystal of the 
 compound, when touched under this instrument with a very 
 small drop of the acid, will yield a very distinct coloration. It 
 must, however, be borne in mind, that a solution of strychnine 
 may be too dilute to yield any precipitate whatever with this 
 reagent, and yet it may have a distinctly bitter taste, and leave 
 upon spontaneous evaporation, even of a single drop of the solu- 
 tion, a residue, which when examined by the color test in the 
 ordinary manner, wiU yield very satisfactory results. State- 
 ments have been made in regard to the delicacy of the reac- 
 tion of this test, which are well calculated to lead to erroneous 
 conclusions. 
 
 For the separation of the precipitate, for the application of 
 this confirmatory reaction, from dilute solutions of the alkaloid, 
 it is best to stir the mixture, by means of a glass rod, in a 
 watch-glass, and then allow it to repose for about half an hour, 
 when the crystallised deposit will be found strongly adherent to 
 the glass, and thus permit of the ready separation of the super- 
 natant liquid by decantation. Or, the mixture may be allowed 
 to evaporate spontaneously to dryness, and the residue touched 
 with a drop of pure water, which will readily dissolve any ex- 
 cess of the reagent present, while the attached crystals of the 
 strychnia compound will remain. 
 
 As bichromate of potash also produces yeUow crystalline 
 precipitates with brucine, narceine, codeine, and some few other 
 principles, and amorphous deposits with morphine, narcotine, 
 and a number of other substances, it is obvious, that the mere 
 production of even a crystalline precipitate by this reagent, is 
 not in itself positive evidence of the presence of strychnine. 
 However, the crystalline form of the strychnine compound, as 
 usually produced, is somewhat peculiar ) and when the crystals 
 yield a positive reaction with sulphuric acid, the results are 
 perfectly unequivocal. Even a positive reaction by this acid 
 from an amorphous deposit, would exclude every other known 
 substance, except the active principle of certain kinds of the 
 woorara poison. By this method, therefore, the two most char- 
 acteristic tests yet known for the recognition of strychnine, may 
 be applied to the same quantity of the poison. 
 
570 STRYCHNINE. 
 
 Protochromate of Potash occasions no precipitate in neutral 
 solutions of salts of strychnine, unless they be very concen- 
 trated. But with acidulated solutions — providing they do not 
 contain very large excess of a mineral acid — it produces results 
 similar to those by the bichromate, due to the fact that the free 
 acid converts the reagent, in part at least, into the latter salt. 
 One grain of a 100th neutral solution of the alkaloid, yields, 
 especially after a little time, a quite good crystalline deposit, 
 very similar to that produced by sulphocyanide of potassium 
 (Plate X, fig. 2). This, however, is very nearly the limit of 
 the reaction of the reagent under these conditions. 
 
 6. Chloride of Gold. 
 
 Terchloride of gold produces in solutions of salts of strych- 
 nine, even when highly dilute, a yellowish amorphous precipi- 
 tate, which after a time becomes more or less crystalline. The 
 precipitate is insoluble in acetic acid, and only sparingly soluble 
 in diluted nitric acid ; when treated with caustic potash, it 
 slowly assumes a dark color. 
 
 !• Toir grain of strychnine, in one grain of water, yields a very 
 copious deposit, which at first has an orange-yellow color, 
 but soon becomes yellow and more or less crystalline, form- 
 ing groups of bush-like crystals, and granules. If the 
 precipitate contains even but little foreign matter, it may 
 remain amorphous. 
 
 2. Trro"o grain : a copious, yellow precipitate, which in a little 
 
 time, becomes converted into groups of crystals, Plate 
 X, fig. 5. _ 
 
 3. r o.ooo grain, yields a very satisfactory, yellowish deposit, 
 
 which soon furnishes small crystalline groups, 
 ■i' 2b \ grain : a very satisfactory turbidity. 
 • 5. 5 0,000 grain, yields a very distinct cloudiness. 
 
 When the precipitate from ten grains of a 5,000th or more 
 dilute solution of the alkaloid, is boiled in the mixture, the de- 
 posit dissolves to a clear yellow solution, and it is re-deposited 
 with little or no change as the liquid cools ; the precipitates 
 from stronger solutions, when treated in this manner, do not 
 
BICHLORIDE OF PLATINUM TEST. 571 
 
 entirely dissolve, but undergo more or less decomposition, with 
 the deposition of metallic gold upon the sides of the tube. 
 Caustic potash dissolves the precipitate from a 5, 000th solution 
 to a clear liquid ; but the deposit from stronger solutions, is not 
 readily soluble in this mineral alkali. Upon the application of 
 heat, the potash solution acquires a purplish color, and throws 
 down a precipitate. 
 
 Chloride of gold also produces yellow precipitates with many 
 other substances, but the crystalline form of the strychnine de- 
 posit is somewhat peculiar. The formation of these crystals, 
 however, as already intimated, is readily interfered with by the 
 presence of foreign matter. 
 
 7. Bichloride of Platinum. 
 
 This reagent produces in solutions of salts of strychnine, a 
 pale-yellow amorphous precipitate, which soon becomes crys- 
 talline. The precipitate, especially when it has assumed the 
 crystalline form, is insoluble in acetic and diluted nitric acids ; 
 it is unchanged in color and only sparingly soluble in caustic 
 potash. 
 1. Yo^Q- grain of strychnine, yields a very copious precipitate, 
 
 which soon becomes a mass of crystals. 
 2- 1,0 grain : a very good deposit, which is soon converted 
 
 into beautiful crystals, Plate X, fig. 6. 
 
 3. 5,0 grain : by stirring the mixture, it yields, after a few 
 
 moments, a granular deposit, and after a few minutes, a 
 quite good crystalline precipitate. 
 
 4. 10,000 grain, yields after a little time, if the mixture has 
 
 been stirred, a quite satisfactory deposit of stellate groups 
 
 of crystals, and granules. 
 This reagent also produces yellow crystalline precipitates 
 with nicotine, potash, and ammonia, a granular deposit with 
 morphine, and amorphous precipitates with a number of sub- 
 stances ; but the strychnine precipitate is usually readily dis- 
 tinguished from these by its crystalline form. In mixtures 
 containing much foreign organic matter, however, the strych- 
 nine compound may not assume the crystalline state. 
 
572 STRYCHNINE. 
 
 Chloride of Falladium throws down from solutions of salts of 
 strychnine a yellow precipitate, which assumes the same crys- 
 talline form as that produced by the platinum reagent ; the limit 
 of the reaction is also the same. 
 
 8. Carbasotic Acid. 
 
 An alcoholic solution of carbazotic acid occasions in solu- 
 tions of salts of strychnine a yellow precipitate of the carbazo- 
 tate of strychnia, which is only sparingly soluble in large excess 
 of acetic acid, and in alcohol. The precipitate is readily solu- 
 ble, to a colorless solution, in sulphuric acid, and the mixture, 
 when treated with a color-developing agent, yields the peculiar 
 strychnine-series of colors ; not, however, in the same intensity 
 as many of the other salts of the alkaloid. 
 !• TW grain of strychnine, yields a very copious, amorphous 
 
 precipitate, which slowly becomes converted into a mass 
 
 of irregular crystalline tufts. 
 
 2. r:^"o grain : a very good precipitate, which soon becomes 
 
 changed into crystals, having the very singular forms illus- 
 trated in Plate XI, fig. 1. 
 
 3. 10,000 grain: on stirring the mixj;ure, it yields, after a little 
 
 time, a very satisfactory, granular deposit. 
 
 4. 2 5,0 -0 grain, yields after a little time, if the mixture has 
 
 been stirred, a quite perceptible, granular precipitate. 
 Carbazotic acid also produces crystalline precipitates with 
 various other substances. The crystalline form, however, of 
 the strychnia compound is somewhat peculiar. 
 
 9. Corrosive Sublimate. 
 
 Chloride of mercury throws down from concentrated neutral 
 solutions of salts of strychnine a white amorphous precipitate 
 of the double chloride of strychnine and mercury, which is 
 readily soluble in acids, even acetic acid. After a time, the 
 precipitate becomes crystalline, 
 
 1. Yoo^ grain of strychnine, yields a very copious precipitate, 
 which in a little time becomes somewhat granular, then 
 
lODOHYDRARGYRATE OF POTASSIUM TEST. 573 
 
 changes into groups of radiating crystals, usually attached 
 to a granular nucleus, and aggregations of large granules, 
 Plate XI, fig. 2. The general form of these crystals, is 
 readily modified by slight circumstances. 
 
 2. Too" grain : after some minutes, the mixture yields a quite 
 satisfactory precipitate of stellate crystals. 
 In solutions but little more dilute than the last-mentioned, 
 
 the reagent fails to produce a precipitate, even after long repose. 
 
 10. lodohydrar gyrate of Potassium. 
 
 This reagent may be prepared by dissolving one part of 
 pure corrosive sublimate in one hundred parts of water and 
 then adding just sufficient iodide of potassium to redissolve the 
 scarlet precipitate first produced, which will require very nearly 
 four parts of the iodine compound. A small quantity of this 
 mixture throws down from solutions of salts of strychnine a dull 
 white precipitate of the double iodide of strychnine and mer- 
 cury, which is insoluble in excess of the precipitant and in the 
 caustic alkalies, as well as in acetic and hydrochloric acids. 
 The precipitate is also insoluble in alcohol ; concentrated sul- 
 phuric acid readily decomposes it with the production of a 
 reddish-brown or purplish color. 
 
 !• To^o" grain of strychnine, in one grain of water, yields a very 
 copious curdy precipitate, which after a little time becomes 
 partly converted into granules and short crystalline nee- 
 dles. If the reagent contain an excess of iodide of potas- 
 sium, the precipitate assumes the same crystalline form as 
 when this salt alone is employed as the precipitant. 
 
 2. 1 J u grain, yields a rather copious precipitate. 
 
 3. 10,000 grain: a quite good precipitate, which in a little time 
 
 becomes converted into opake granules and short irregular 
 needles. On the addition of a few drops of acetic or 
 hydrochloric acid, the precipitate is soon changed into 
 irregular groups of rather long needles. 
 
 4. 5 0,0 grain, yields a quite distinct precipitate, and in a 
 
 little time, a very satisfactory deposit. This deposit is 
 very similar in appearance to that produced from dilute 
 
574 STRYCHNINE. 
 
 solutions of atropine by bromohydric acid, as illustrated 
 
 in Plate XII, fig. 6. 
 5. 10 0% grain : no immediate change, but in a very little 
 
 time, the mixture becomes cloudy, and soon yields a very 
 
 satisfactory deposit of opake granules and short irregular 
 
 needles. 
 The production of a white precipitate by this reagent is 
 common to solutions of most, if not all, of the alkaloids. 
 
 11. Ferricyanide of Fotassium, 
 
 Red Prussiate of potash produces in quite strong neutral 
 solutions of salts of strychnine a yellowish amorphous precipi- 
 tate, which in a little time becomes crystalline. The precipitate 
 is only slowly soluble in acetic acid, but readily soluble in the 
 stronger acids, and is, therefore, not produced in their presence. 
 1. YoTT grain of strychnine, yields a quite cofious precipitate, 
 which in a few moments becomes converted into a mass of 
 beautiful groups of crystals, Plafe XI, fig. 3. 
 2- To"o^ grain, yields a very good crystalline precipitate. 
 3. iTF^oT) grain, yields little or no indication of the presence of 
 the poison, even after the mixture has stood half an hour 
 or longer. 
 
 When a small portion of the precipitate, occasioned by this 
 reagent, is treated with a drop of concentrated sulphuric acid, 
 it, like that produced by the bichromate of potash, dissolves 
 with the production of the same series of colors as obtained by 
 the color test as ordinarily applied. The least visible crystal 
 of the deposit wiU respond to this reaction. It will be observed, 
 however, that as a precipitant for strychnine, ferricyanide of 
 potassium in point of delicacy, is far inferior to bichromate 
 of potash. 
 
 Nitro-prusside of Sodium throws down from neutral solutions 
 of salts of strychnine a white or dirty-white precipitate, which 
 assumes the same crystalline form as that produced by ferri- 
 cyanide of potassium, and the limit of the reaction is about 
 the same. But, notwithstanding the contrary has been as- 
 serted, this precipitate, unlike that occasioned by ferricyanide 
 
IODINE TEST. 575 
 
 of potassium, dissolves without change of color in concentrated 
 sulphuric acid. 
 
 Ferrocyanide of Potassium, fails to precipitate solutions of 
 salts of strychnine, unless very concentrated and perfectly neu- 
 tral. One grain of a 100th solution of the alkaloid will yield 
 a quite good crystalline deposit; but this is very nearly the 
 limit of the reaction. 
 
 12. Iodine in Iodide of Potassium. 
 
 An aqueous solution of iodine in iodide of potassium pro- 
 duces in solutions of salts of strychnine, even when highly 
 diluted, a reddish-brown amorphous precipitate, which is read- 
 ily soluble in alcohol, but only very sparingly soluble in acetic 
 acid. The precipitate is readily soluble in caustic potash, but 
 it is soon replaced by a white deposit. Dr. W. B. Herapath 
 has shown (Chem. Gaz., 1855, p. JJ20), that an alcoholic solu- 
 tion of strychnine yields with iodine, crystalline compounds, 
 having very peculiar optical properties. 
 
 1. xoi7 grain of strychnine, yields a very copious deposit, which 
 
 after a time becomes more or less crystalline. 
 
 2. 1,000 grain : a copious precipitate, which after a time be- 
 
 comes, in part at least, converted into crystals, Plate XI, 
 fig. 4. These crystals are most readily obtained when 
 large excess of the reagent is avoided. 
 
 3. 10.000 grain, yields a very good precipitate, which readily 
 
 dissolves to a colorless solution in caustic potash, but after 
 a little time the mixture becomes turbid. The precipitate 
 is slowly converted into crystalline nodules. 
 
 4. 5 0,0 grain, yields a very satisfactory deposit. 
 
 5. 10 0% grain, furnishes a very distinct turbidity. 
 
 This reagent also produces precipitates with a variety of 
 organic substances, and with certain inorganic compounds, but 
 the character of the strychnine crystals is quite peculiar; their 
 formation, however, is readily interfered with by the presence 
 of foreign matter. 
 
 The strychnine may be recovered from the washed precipi- 
 tate, by dissolving the latter in strong alcohol, and treating the 
 
576 STRYCHNINE. 
 
 \ 
 
 solution with slight excess of nitrate of silver, which will pre- 
 cipitate the iodine as iodide of silver ; this is removed by a 
 filter, and the excess of the silver reagent precipitated from the 
 filtrate by the cautious addition of diluted hydrochloric acid; 
 the chloride of silver thus produced is then separated by a filter, 
 and the filtrate evaporated to dryness on a water-bath, when 
 the strychnine will be left in its pure state. This method will 
 serve for the recovery of even extremely minute quantities of 
 the alkaloid. 
 
 13. Bromine in BromoJiydric Acid. 
 
 A strong aqueous solution of bromohydric acid saturated 
 with bromine, occasions in solutions of salts of strychnine, even 
 when very dilute, a yellow amorphous precipitate, which is 
 readily soluble in alcohol, and in acetic acid. The precipitate 
 remains amorphous. 
 
 1. yoir grain of strychnine, yields a very copious, bright-yellow 
 
 deposit, which after a time disappears, but it is reproduced 
 upon further addition of the reagent. 
 
 2. 1,000 grain, yields a copious precipitate. 
 
 3. 10,0 grain : a very good deposit. 
 
 4. Tu7o"o"o grain, yields a very satisfactory, yellow precipitate. 
 
 5. 10 0% grain, yields a distinct turbidity, which after a time 
 
 disappears, and is not reproduced upon further addition of 
 the reagent. 
 The reaction of this reagent is common to a large class of 
 organic substances. 
 
 14. Physiological Test. 
 
 Dr. Marshall Hall proposed to take advantage of the extreme 
 sensibility of frogs to the efiects of strychnine, as a means of 
 detecting its presence. He advised to immerse the frog to be 
 experimented upon, in a solution of the poison ; when sooner or 
 later, according to the strength of the solution, the animal is 
 seized with violent tetanic convulsions, in which the extremi- 
 ties become extended to their uttermost and the whole body 
 
PHYSIOLOGICAL TEST. 577 
 
 perfectly rigid. By this method Dr. Hall states that he was 
 enabled to detect the 5,000th part of a grain of strychnine. 
 More recently Dr. Harley proposed to inject the strychnine 
 solution into the thoracic or abdominal cavity of the animal ; 
 and he states that the 16,000th part of a grain of the acetate 
 of strychnia introduced into the lungs of a very small frog, will 
 render it violently tetanic in about ten minutes. 
 
 In the following examinations of this test, about two grains 
 of the strychnine solution were taken up by a pipette, the filled 
 end of which was then introduced into the stomach of the frog, 
 and the liquid discharged by blowing through the tube. The 
 animals were then placed under an open glass receiver. The 
 frogs were fresh, and varied in weight from fifteen to fifty 
 grains. The results for each quantity of the poison are based 
 upon numerous experiments, and chiefly upon the species of 
 animal known as JRana Halecina. 
 
 1. 100th solution — equal to about the 50th of a grain of strych- 
 
 nine — usuaUy produces immediate and violent spasms, and 
 death in about eight minutes. 
 
 2. 1,000th solution : the symptoms generally manifest them- 
 
 selves in three or four minutes, and death usually takes 
 place in from fifteen to thirty minutes. 
 
 3. 10,000th solution: in some instances the symptoms appeared 
 
 within ten minutes, while in others they were delayed as 
 long as half an hour. 
 
 4. 20,000th solution, generally produces characteristic symp- 
 
 toms in from thirty to forty-five minutes ; but in some 
 few instances the results were not well marked, even after 
 long periods. 
 
 5. 30,000th solution, or the 15,000th of a grain of strychnine : 
 
 in most instances, especially when very small animals were 
 
 employed, the symptoms appeared within fifty minutes ; 
 
 but in some cases there were no marked effects, even after 
 
 some hours. 
 
 In applying this test, the frogs should always be fresh from 
 
 the pond. Occasional agitation of the animal hastens the action 
 
 of the smaller quantities of the poison ; and frequently a violent 
 
 paroxysm may be induced by a sudden noise, such as clapping 
 
 37 
 
578 STRYCHNINE. 
 
 of the hands. From experiments made at different times, we 
 are strongly inclined to believe that the sensibility of this animal 
 to the effects of strychnine, differs somewhat with the seasons 
 of the year. The Spring and early part of the Summer seem 
 to be the most favorable for the application of the test. It may 
 be remarked, that in regard to weight, the 20,000th of a grain 
 of strychnine bears about the same relation to a frog weighing 
 twenty-five grains, that two grains do to a man weighing one 
 hundred and forty pounds. When, therefore, the foregoing 
 experiments are taken in connection with the known effects of 
 this poison upon the human subject, it would appear, that, if 
 any difference, the frog was relatively somewhat less sensitive 
 than man to its action. 
 
 This physiological test certainly affords a very valuable 
 means of corroborating the chemical evidence of the presence 
 of strychnine, and at the same time, as we have just seen, it is 
 extremely delicate ; yet it should never be employed to the ex- 
 clusion of at least some of the chemical tests. In regard to 
 delicacy, for the pure alkaloid, it is much inferior to the color 
 test, the latter yielding satisfactory results with a quantity of 
 the poison that would produce no appreciable effect upon a frog, 
 even of the smallest size. 
 
 Other Reagents. — Chlorine gas passed into somewhat strong 
 solutions of salts of strychnine produces a white amorphous pre- 
 cipitate. Ten grains of a 1,000th solution of the alkaloid yields 
 a quite good deposit, which is unchanged upon the addition of 
 ammonia ; a similar quantity of a 10,000th solution yields a 
 distinct milkiness, which quickly disappears on the addition of 
 ammonia. 
 
 Tannic acid, phosphomolybdic acid, a solution of perchloride 
 of antimony in phosphoric acid, and Nessler's test for ammonia, 
 also precipitate strychnine from solutions of its salts, even in 
 some instances when highly diluted. But as the reactions of 
 these reagents "are common to a large class of organic com- 
 pounds, the results have little or no positive value. Gallic acid 
 fails to produce a precipitate, even in highly concentrated solu- 
 tions of salts of the alkaloid. 
 
SEPARATION FROM ORGANIC MIXTURES. 579 
 
 Separation from Organic Mixtures. 
 
 From Nux Vomica. — Strychnine may be separated from 
 powdered nux vomica, by digesting the powder, for some time, 
 at a moderate heat with a small quantity of water slightly acid- 
 ulated with acetic acid ; when the decoction has cooled, it is 
 filtered, and the filtrate concentrated over a water-bath to a 
 small volume. The concentrated solution, which will have the 
 intensely bitter taste of the alkaloid, is now treated with slight 
 excess of caustic potash or soda, and violently agitated with its 
 own volume or more of chloroform. After the liquids have 
 completely separated, the chloroform is carefully withdrawn, 
 and allowed to evaporate spontaneously in a watch-glass, when 
 the alkaloid will be left, usually in its amorphous state, together 
 with more or less foreign matter. 
 
 The residue thus obtained may either be examined at once 
 by the chemical tests or be further purified, by dissolving it in 
 a very small quantity of acidulated water, rendering the solu- 
 tion alkaline, and again extracting with chloroform. After 
 examining a portion of the residue by the color test, any re- 
 maining portion may be dissolved in a small quantity of water 
 containing a trace of acetic acid, and the solution examined by 
 the bichromate of potash, or any of the other liquid tests for 
 the alkaloid. A single grain of powdered nux vomica, in its 
 free state, when treated after the above method, will yield very 
 satisfactory evidence of the presence of strychnine. 
 
 Suspected Solutions and Contents of the Stomach. — 
 Any organic solids present in the mixture presented for ex- 
 amination, are cut into small pieces and the mass, after the 
 addition of water if necessary, treated with about half its vol- 
 ume of strong alcohol and sufficient acetic acid to give it a dis- 
 tinctly acid reaction. The acidulated mixture is now digested 
 at a moderate heat on a water-bath, with frequent stirring, for 
 about half an hour or longer. It is then, after cooling, thrown 
 upon a wet linen strainer, and the solid residue well washed 
 with diluted alcohol, and strongly pressed. The mixed strained 
 fluids are concentrated at a moderate temperature to a small 
 
580 STRYCHNINE. 
 
 volume, again strained, and if practicable filtered, then evap- 
 orated on a water-bath to about dryness. Any strychnine 
 present, wiU now be in the residue, in the form of acetate of 
 strychnia, mixed with more or less foreign matter. 
 
 The residue, obtained by this operation, is thoroughly stirred 
 with a small quantity of water containing a drop of acetic acid, 
 the mixture filtered, the filter washed with a little water, and 
 the mixed filtrates, after concentration if necessary, transferred 
 to a stout test-tube or small bottle, and treated with slight ex- 
 cess of caustic potash or soda, by which the strychnine wiU be 
 set free from its saline combination. Should the mixture con- 
 tain a comparatively large quantity of the alkaloid, the latter 
 may after a time assume the crystalline form. The alkaline 
 mixture is now violently agitated for about a minute with some- 
 thing more than its own volume of pure chloroform. When the 
 liquids have completely separated, the supernatant aqueous fluid 
 is carefully transferred, by means of a pipette, to another test- 
 tube, and the chloroform decanted into a watch-glass, great care 
 being taken that no remaining drops of the aqueous liquid pass 
 over with the chloroform ; the alkaline aqueous mixture is then 
 washed with a fresh portion of chloroform, and this collected 
 with that first employed. A very good method for separating 
 the last drops of the aqueous liquid from the decanted chloro- 
 form, is to collect the latter liquid in a dry test-tube and decant 
 it from this into the watch-glass : the last traces of the former 
 fluid will now usuaUy remain attached to the sides of the tube. 
 If, however, the chloroform has stiU a milky appearance, the 
 liquid may be passed through a small paper-filter, previously 
 moistened with pure chloroform. 
 
 The decanted chloroform, which contains any strychnine that 
 was present in the alkaline mixture, is now allowed to evaporate 
 spontaneously to dryness. If the liquid contained a very nota- 
 ble quantity of the alkaloid, the latter may remain in its crys- 
 taUine form : this result, however, is rarely obtained from the 
 first chloroform extract, when operating on the contents of a 
 stomach containing the poison. A portion of the residue may 
 be examined by the color test, as also by the taste ; and 
 any -remaining portion dissolved in an appropriate quantity of 
 
SEPARATION FROM ORGANIC MIXTURES. 581 
 
 distilled water containing a trace of acetic acid, and the solution, 
 after filtration if necessary, examined by some of the liquid 
 tests for strychnine, beginning with the bichromate of potash. 
 If, however, the examination of a small portion of the dry resi- 
 due indicate the presence of much foreign matter, the acidu- 
 lated a"queous solution is rendered alkaline, again extracted by 
 chloroform, and this liquid separated and evaporated as before, 
 when the alkaloid, even if present only in very minute quan- 
 tity, will usually be left in its crystalline state, or at least 
 sufficiently pure for the application of the most important tests. 
 When the mixture presented for examination is extremely 
 complex, as is frequently the case with the contents of the 
 stomach, it sometimes happens that on agitating the prepared 
 alkaline solution with chloroform, the whole becomes a white 
 frothy emulsion, from which the chloroform will not separate, 
 ' even after several hours. When this occurs, the mixture may 
 be moderately agitated with about half its volume of piire water, 
 and the whole allowed to repose, if necessary, for some hours, 
 when more or less of the water will separate as a highly colored 
 fluid ; this is decanted, and the operation repeated with fresh 
 portions of water as long as the liquid becomes colored. By 
 this means, much of the foreign matter will be separated, while 
 any strychnine present will remain in solution in the chloroform 
 mixture, at most only the merest trace of it being taken up by 
 the decanted water. The mixture is now slightly acidulated by 
 a drop or two of acetic acid. It may then be transferred to a 
 small dish and evaporated to dryness on a water-bath, and the 
 residue stirred with a very small quantity of pure water, the 
 solution, after filtration if necessary, rendered slightly alkaline, 
 and again agitated with fresh chloroform, which will now usually 
 readily separate. Instead of treating the acidulated chloroform 
 mixture in the manner just described, it may be agitated with 
 consecutive portions of pure water as long as this liquid acquires 
 a bitter taste, when the alkaloid will be extracted as acetate of 
 strychnia, and be left as such on evaporating the solution to 
 dryness over a water-bath. t 
 
 On applying the general method now described, to the ex- 
 amination of the contents of the stomach of several different 
 
582 STRYCHNINE. 
 
 cats, each of which had been killed by half a grain of strych- 
 nine, we in no instance failed to recover the poison in quanti- 
 ties several times more than sufficient to fully establish its true 
 nature in the most satisfactory manner. The only instance 
 among these in which a quantitative analysis was performed, 
 was in the case of a young cat, to which th,e poison had been 
 administered in solution, upon a very full stomach, and death 
 ensued in ten minutes ; the third chloroform extract furnished 
 yV-Q-ths of a grain of the pure crystallised alkaloid. During the 
 purification of the alkaloid in this case, there was, of course, a 
 very notable quantity of the poison, which would have been 
 available for qualitative purposes, lost. 
 
 On following the same method in a recent case, for the 
 examination of the contents of the stomach of a man, who had 
 died from the efi'ects of strychnine, administered, there is every 
 reason for believing, in comparatively small quantity, iVoths of 
 a grain of the pure alkaloid, chiefly in its crystalline state, were 
 recovered. And in another case, in which an unknown quan- 
 tity of the poison had been administered and death took place 
 in about an hour, the final residue furnished -j^oVths of a grain 
 of the pure alkaloid. 
 
 Method by Dialysis. — To apply this process, the details of 
 which have heretofore been pointed out (ante, p. 420), the 
 organic mixture, acidulated with acetic or hydrochloric acid, is 
 prepared in the manner already described for the examination 
 of the contents of the stomach, and the concentrated solution 
 placed in the dialyser, which is then floated in a dish contain- 
 ing four or five times as much pure water as the volume of 
 fluid to be dialysed ; after twenty-four or thirty-six hours, the 
 diffusate is transferred to a porcelain dish, evaporated to dry- 
 ness on a water-bath, and the residue examined. 
 
 In regard to the relative merits of this method, even with 
 mixtures containing comparatively large quantities of strych- 
 nine, experiments indicate that the difinsate usually becomes 
 contaminated to such an extent with foreign matter, that to 
 separate the alkaloid from this, requires just the same opera- 
 tions as required to recover it directly, by the ordinary methods, 
 from the original mixture ; moreover, the relative quantity of 
 
RECOVERY BY DIALYSIS. 583 
 
 the alkaloid that passes into the difFusate, even after twenty- 
 four or thirty-six hours, never exceeds the proportion existing 
 between the volume of liquid in the difFusate and that in the 
 dialyser. Of many experiments, in support of the statements 
 just made, that might be mentioned, the two following may 
 be cited : — 
 
 1st. Three-quarters of a grain of strychnine, in solution, 
 were administered to a cat, which had recently been fed ; in 
 about four minutes, the animal was seized with violent tetanic 
 convulsions and died during the paroxysm. The contents of 
 the stomach, together with the cut-up tissue of the organ, were 
 mixed with six ounces of distilled water containing about half 
 its volume of alcohol, the whole acidulated with acetic acid, and 
 digested on a water-bath for twenty minutes ; then strained and 
 the solution concentrated to twelve fluid drachms. This solu- 
 tion was then dialysed, with five volumes of pure water as the 
 diffusate, for forty hours. 
 
 a. The diffusate was now concentrated on a water-bath to 
 one fluid drachm, when it formed a highly turbid, reddish-brown 
 mixture, having a decidedly acid reaction and intensely bitter 
 taste ; the liquid was then filtered, rendered alkaline by potash, 
 and agitated with little more than its own volume of pure chlo- 
 roform. This liquid, after some difSculty, was separated, the 
 aqueous fluid washed with a fresh portion of chloroform, and 
 the mixed chloroforms allowed to evaporate spontaneously. The 
 residue, obtained by this operation, was amorphous, and evi- 
 dently contained a large proportion of foreign matter, although 
 the least portion of it, when examined by the color test, very 
 plainly indicated the presence of strychnine. On stirring the 
 deposit with a small quantity of acidulated water, it furnished a 
 quite turbid mixture. This was filtered, and the filtrate, after 
 the addition of a drop of potash, again extracted by chloroform, 
 which upon spontaneous evaporation, left the alkaloid in its pure 
 state, and chiefly in the crystalline form. The residue, when 
 perfectly dried, weighed x^o'ths of a grain. 
 
 h. The contents of the dialyser were evaporated to dryness, 
 the residue stirred with about a drachm of acidulated water, 
 the solution passed repeatedly through a plug of raw cotton, 
 
584 STRYCHNINE. 
 
 then rendered alkaline, and agitated with about its own volume 
 of chloroform. This fluid, which readily separated, was then, 
 together with a fresh portion of the liquid used for washing the 
 aqueous mixture, exposed to spontaneous evaporation, when it 
 left a small residue, which contained some few crystals of pure 
 strychnine ; but it was quite evident that the amorphous part of 
 the deposit contained a large proportion of foreign matter. On 
 now dissolving the residue in acidulated water, and again ex- 
 tracting the solution in the ordinary manner by chloroform, this 
 liquid, on spontaneous evaporation, left the alkaloid in its pure 
 state, and principally in the crystalline form .; this residue, when 
 dried, weighed y^ths of a grain. 
 
 It will be observed, in the case now detailed, that although 
 the conditions, both in regard to the time the dialysation was 
 continued and the quantity of fluid employed for the difFusate, 
 were most favorable for the diffusion ; yet, nearly one half as 
 much strychnine was obtained from the mixture dialysed as 
 from the difiiasate, and with about the very same operations as 
 employed in the examination of the latter. The labor consumed 
 by the two operations was, therefore, apparently fully twice 
 that which would have been required to separate the poison at 
 once from the original mixture ; and, at the same time, there is 
 little doubt but more of the alkaloid would have been recovered 
 in this manner than by the two separate operations. It is, 
 however, but proper to add, that perhaps more difficulty would 
 have been experienced in the purification of the original mix- 
 ture before subjecting it to the process of dialysis, than there 
 was after this operation. 
 
 2d. The finely-divided liver of a cat, which had been killed 
 by a blow upon the head, was gently boiled with several ounces 
 of water acidulated with hydrochloric acid, until the organic 
 matter was well broken up ; the mixture was then strained, and 
 the solution concentrated to twelve fluid drachms. Half a grain 
 of pure strychnine was now added to the concentrated liquid, 
 and the mixture dialysed, with five volumes of pure water, for 
 thirty-seven hours. 
 
 The dijfusate was then evaporated to dryness, the gummy 
 residue dissolved in a small quantity of water, the solution 
 
RECOVERY BY DIALYSIS. 585 
 
 filtered, then rendered alkaline, and agitated with chloroform. 
 This fluid separated readily, and when evaporated spontane- 
 ously, left a comparatively large residue, consisting principally 
 of crystals of pure strychnine. The deposit was again dissolved 
 in a small quantity of liquid, and the solution extracted a sec- 
 ond time by chloroform. On spontaneous evaporation, the chlo- 
 roform now left a residue of pure crystallised strychnine, which, 
 when thoroughly dried, weighed -j^oTfths of a grain. 
 
 The mixture in the dialyser was concentrated on a water- 
 bath to six fluid drachms, then strained through cotton, and the 
 turbid solution evaporated to dryness, when it left a quite large, 
 gummy residue. This was stirred with a little water, and many 
 attempts made to clear the mixture by filtration, but the liquid 
 still remained turbid. It was then rendered alkaline, and agi- 
 tated with chloroform, with which it formed a white saponaceous 
 mass from which the chloroform would not separate. This was 
 now washed several times with pure water, then acidulated with 
 acetic acid, and evaporated to dryness, the residue dissolved in 
 water, the solution filtered, then rendered alkaline and again 
 agitated with chloroform. About three-fourths of this liquid 
 readily separated, but the remaining portion did not, even after 
 some hours. The clear chloroform was now removed, and the 
 frothy mixture again evaporated to dryness, and the residue, 
 after solution and filtration, extracted with fresh chloroform, 
 which now readily separated. The mixed chloroforms were 
 then allowed to evaporate spontaneously, when they left a 
 residue of pure strychnine, chiefly in the form of large col- 
 orless stellate crystals, which, when dried, weighed xToths of 
 a grain. 
 
 It will be observed that in this instance the purification of 
 the dialysed mixture was attended with much more difficulty 
 than in the preceding experiment ; and that the reverse, to a 
 certain extent, was true in regard to the diff^usate. It also ap- 
 pears, that the alkaloid, in this case, distributed itself between 
 the difiiisate and fluid in the dialyser, very nearly in the pro- 
 portions of the volumes of these liquids ; and that only eight 
 per cent, of the strychnine was lost in the experiment. The 
 two instances now cited represent about the extremes, in 
 
586 STRYCHNINE. 
 
 regard to restilts, of several experiments of this kind that might 
 be adduced. 
 
 From the Tissues. — The soft organ, such as a portion of 
 the liver, is placed in a porcelain evaporating dish, and cut into 
 very small pieces, taking care that none of the fluid present is 
 lost; the mass is rendered suiSciently liquid by water, some 
 strong alcohol added, and the whole well stirred, and acidulated 
 with sulphuric acid, in the proportion of about eight drops of 
 the concentrated acid for each fluid ounce of the mixture. It 
 is then digested at a temperature of about 180° F., with fre- 
 quent stirring, for half an hour or longer, and, after cooling, 
 strained through a fine linen cloth, the residue washed with 
 acidulated water and strongly pressed. 
 
 The strained liquid, including the washings, thus obtained, 
 is concentrated on a water-bath, and, when much solid matter 
 has separated, again strained, these operations being repeated 
 until the fluid is reduced to a small volume. This is nearly 
 neutralised with caustic potash, taking care however that the 
 mixture still retains a very decided acid reaction'; then filtered, 
 and the filtrate evaporated, on a water-bath, until only a few 
 drops of liquid remain. When this residue has cooled, it is well 
 stirred with about half an ounce of concentrated alcohol, which 
 will dissolve, in the form of sulphate, any strychnine present, 
 while the sulphate of potash, formed from the sulphuric acid 
 and potash added, together with more or less of the foreign 
 organic matter, will remain undissolved. The alcoholic solution, 
 after filtration, is evaporated on a water-bath to almost dryness, 
 the residue stirred with a small quantity of pure water, and the 
 filtered solution rendered slightly alkaline by caustic potash or 
 soda. It is then agitated with pure chloroform in the usual 
 manner, and this fluid, after careful separation, allowed to evap- 
 orate spontaneously. 
 
 If on stirring the above nearly dry residue with concen- 
 trated alcohol, for the separation of the poison from the sulphate 
 of potash, it should form a tenacious gummy mass that will not 
 mix with the liquid — as is sometimes the case, especially when 
 the subject under examination is the liver — the fluid is expelled 
 by evaporation, the residue stirred with water, the filtered 
 
RECOVERY FROM THE BLOOD. 587 
 
 solution evaporated to nearly dryness, and the residue again 
 treated with alcohol, with which the deposit will now usually 
 readily mix. Again, should the final alkaline solution when 
 agitated with chloroform, form a white emulsion from which the 
 chloroform will not separate, the mixture is treated after one or 
 other of the methods before described for mixtures of this kind. 
 
 The sixth of a grain of strychnine, in solution, was given to 
 a healthy cat, which had just been fed. Twelve minutes after- 
 wards, the animal was seized with violent tetanic symptoms, 
 and died three minutes later. The liver, together with the con- 
 tained blood, was then treated after the preceding method. The 
 first chloroform solution thus obtained, left on spontaneous evap- 
 oration, a very small gummy residue, which when examined in 
 three separate portions by the color test, gave, in each instance, 
 perfectly satisfactory evidence 'of the presence of strychnine. 
 Although the quantity of the poison thus recovered, was even 
 more than sufficient to fully establish its presence by this test ; 
 yet it was, probably, too minute to have permitted the reaction 
 of this test being confirmed by any of the other tests, except 
 by the taste. Whether the strychnine recovered in this instance 
 was simply present in the blood contained in the liver, or whether 
 a portion of it had been deposited in the tissue of this organ, is 
 difficult to decide. None of the other tissues of this animal were 
 examined. An analysis of the gall-bladder and its contents, of 
 a similar animal, killed in fifteen minutes by the sixth of a 
 grain of strychnine, failed to reveal the presence of a trace of 
 the poison. 
 
 The Blood. — This fluid may be examined for absorbed 
 strychnine in much the same manner as just described for the 
 analysis of the tissues. About four fluid ounces of the sus- 
 pected blood, placed in a wide-mouthed bottle, are mixed with 
 an equal volume of water and about half a volume of strong 
 alcohol, and about eight minims of concentrated sulphuric acid 
 added for each ounce of blood, and the whole thoroughly agi- 
 tated, until the mixture becomes perfectly homogeneous. It is 
 then heated in a dish, on a water-bath, to near the boiling tem- 
 perature, with constant stirring, for about fifteen minutes, and 
 while still warm, the liquid portion squeezed through a fine 
 
588 STRYCHNINE. 
 
 linen cloth, and the black viscid residue washed with alcohol 
 and pressed. Should the whole of the mixture pass through 
 the strainer, as will be the case if too much acid has been 
 added, it is returned to the dish, treated with a few drops of 
 caustic potash, and again heated for a few minutes, then 
 strained. If, on the other hand, the solid matter separated by 
 the strainer, when pressed, is dry and pulverisable, it is re- 
 turned to the strained liquid, the mixture heated with -a few 
 drops more of sulphuric acid, and again returned to the strainer. 
 
 The highly colored, turbid liquid, thus obtained, is treated 
 with a few drops of caustic potash, so as to somewhat diminish 
 its acidity, then concentrated somewhat, and again strained. 
 The solution is now nearly neutralised by the cautious addition 
 of a caustic alkali, and again heated, when most of the albu- 
 minous matter will separate in the form of little brownish flakes. 
 These are separated, from the cooled mixture, by means of a 
 linen strainer, washed with diluted alcohol, and strongly pressed. 
 If the flocculent matter is not entirely separated by the first 
 straining, in this operation, the fluid is returned to the cloth 
 until it passes through perfectly clear. The liquid will now 
 usually have only a light brownish color, while the separated 
 solids will be dry and pulverisable. 
 
 The clear liquid, thus obtained, is concentrated on a water- 
 bath to a small volume, passed through a small filter, previously 
 moistened with water, the filter washed, and the mixed filtrates 
 evaporated to about dryness. The residue, thus left, is well 
 stirred, by means of a glass rod or the clean finger, with about 
 an ounce of nearly absolute alcohol, the solution filtered, the 
 filter washed with similar alcohol, and the clear liquids evap- 
 orated at a very moderate temperature to almost dryness. This 
 residue is thoroughly stirred with about a drachm of pure water, 
 and the solution filtered. The filtrate may now be examined 
 by the taste. It is then rendered slightly alkaline by caustic 
 soda or potash, and agitated in the ordinary manner with chlo- 
 roform. This liquid, after separation, is allowed to evaporate 
 spontaneously, and the residue examined in the usual manner. 
 In the examination of this residue, the operator should bear in 
 mind, that at most there is only a very minute quantity of 
 
RECOVERY PROM THE BLOOD. 589 
 
 strychnine present, and unless great care be exercised, it may 
 entirely escape detection. 
 
 Absorbed strychnine seems to adhere more tenaciously to 
 the solids of the blood than any other poison, with, perhaps, 
 the single exception of morphine. For its recovery from this 
 fluid, it is essential that the liquid, after the addition of water 
 and alcohol, be at first acidulated as strongly as possible com- 
 patible with the separation of at least a small portion of the 
 solid matter. The exact quantity of acid necessary for this 
 purpose will vary somewhat with difi^erent samples of blood ; it 
 also appears, that sulphuric acid is better adapted than any 
 other acid for this purpose. If the poisoned bloo,d be acidu- 
 lated only moderately, as for the recovery of most of the other 
 alkaloids, the whole of the strychnine wiU usually be separated 
 along with the solid albuminous matter. Before resorting to the 
 method just described, we had followed various methods advised 
 by others, and these variously modified, with the blood of not 
 less than fifteen separate animals, killed by strychnine, without 
 in any instance obtaining distinct evidence of the presence of 
 the poison. In fact, it was only by applying the process under 
 consideration to the solids separated by some of these methods, 
 and thus clearly recovering the poison, that we were led to 
 apply it directly to the blood. 
 
 On following this method for the examination of the blood 
 of six different cats, and of two dogs, poisoned by compara- 
 tively small doses of strychnine, we in every instance obtained 
 perfectly satisfactory and unequivocal evidence of the presence 
 of the poison. In two of these cases, in each of which half a 
 grain of strychnine had been administered to young cats and 
 death took place in three and six minutes respectively, six fluid 
 drachms of blood from each — the whole that was obtained — 
 furnished residues, about the fifth part of each of which, when 
 examined by the color test, gave unquestionable evidence of the 
 presence of the alkaloid. These instances show the extreme 
 rapidity with which a quite notable quantity of the poison may 
 be absorbed. In fact, in these two cases, there was apparently 
 as much strychnine recovered as in those in which life was 
 prolonged for about half an hour. 
 
590 STRYCHNINE. 
 
 In none of these cases did the chloroform leave the strych- 
 nine in a distinctly crystalline form. But in one of them, after 
 the presence of the poison had been shown in a portion of the 
 residue by the color test, the remaining portion, when stirred 
 with a drop of a very dilute solution of bichromate of potash, 
 and the fluid allowed to evaporate spontaneously, furnished a 
 number of octahedral crystals of the chromate of strychnia: 
 this was the only instance in which the residue was thus treated. 
 In every instance, the whole of the blood that could be obtained 
 from the animal, was examined at one operation. It does not, 
 of course, follow, that a given quantity of blood taken from the 
 human subject, poisoned by strychnine, would contain the same 
 amount of the poison as would be present, under like conditions, 
 in a similar quantity of blood from a cat. Indeed, the differ- 
 ence between the smallest fatal dose for the former and that for 
 the latter, seems to be very much less than that between the 
 absolute quantities of blood found in each. 
 
 On following the method of Dialysis, in three different cases, 
 for the examination of the blood of animals poisoned by strych- 
 nine, we in no instance detected a trace of the poison in the 
 diffusate. Previously to introducing the blood into the dialyser, 
 the strongly acidulated fluid was heated for some time with 
 diluted alcohol, then strained and concentrated. On examining 
 the dialysed blood, in one case, by the method heretofore de- 
 scribed, it furnished very distinct evidence of the presence of 
 the poison. 
 
 From the Urine. — Strychnine may be separated from the 
 urine, by acidulating the liquid with a few drops of acetic acid, 
 and evaporating it on a water-bath to a thick syrup. When 
 this has cooled, it is well stirred with about a fluid ounce of 
 nearly absolute alcohol, the solution filtered, and the residue on 
 the filter washed with similar alcohol, and then strongly j)ressed. 
 The yellowish filtrate thus obtained, is concentrated to a thick 
 syrup, and the residue dissolved in a small quantity of pure 
 water. This solution, after filtration if necessary, is rendered 
 slightly alkaline, by either of the fixed caustic alkalies, and 
 agitated in the ordinary manner with pure chloroform, which, 
 after separation, is allowed to evaporate spontaneously, when 
 
FAILURE TO DETECT. 591 
 
 the alkaloid, if present in very notable quantity, will be left in 
 its crystalline state. 
 
 By following this method for the examination of a fluid 
 ounce of normal urine, to which the 100th part of a grain of 
 strychnine has been purposelyi added — the dilution being one 
 part of the poison in about 50,000 parts of the liquid — the 
 alkaloid may be recovered, in the pure crystalline form, with 
 scarcely any appreciable loss. 
 
 One-fourth of a grain of strychnine, in solution, was given 
 to a very large dog, weighing about eighty-five pounds. Slight 
 tetanic symptoms manifested themselves in about fifteen minutes. 
 These continued for about a quarter of an hour, when a second 
 dose, containing a similar quantity of the poison, was adminis- 
 tered. The animal was now soon seized with violent symptoms, 
 but survived the efi'ects of the poison, one hour and three- 
 quarters after the administration of the first dose. Five ounces 
 of urine were recovered from the bladder, and treated after the 
 foregoing method; but the examination failed to reveal any 
 distinct evidence of the presence of strychnine. A second dog, 
 weighing about sixty pounds, was given a quarter of a grain 
 of the acetate of strychnia. Symptoms appeared in twenty 
 minutes, and after twenty minutes more, the animal was found 
 dead. An examination of five and a half ounces of urine 
 obtained from this animal, also failed to indicate the presence 
 of the poison. In this case, the urine was strongly acidulated 
 with sulphuric acid, instead of acetic acid, as in the preceding 
 examinations. In another instance, however, in which the above 
 method was employed, for the examination of two ounces of 
 bloody urine obtained from the bladder of a man, who had died 
 in one hour and three-quarters, from the effects of an unknown 
 quantity of strychnine, the second chloroform residue, when 
 examined by the color test, gave satisfactory evidence of the 
 presence of the poison. 
 
 Failure to Detect the Poison. — It has not unfrequently 
 happened, in fatal poisoning by strychnine, that there was a 
 failure to detect a trace of the poison, even in the contents of 
 the stomach and under circumstances apparently very favorable 
 for its recovery. There is little doubt, but some of these failures 
 
592 STRYCHNINE. 
 
 may be justly attributed to the imperfect methods of analyses 
 employed; yet they have occurred in the hands of the most 
 experienced manipulators. The whole of the poison may be 
 rapidly removed from the stomach by the process of absorption 
 or the act of vomiting, or by these combined ; and, in protracted 
 cases, even that which has been absorbed may l^e entirely elim- 
 inated from the body previous to death. 
 
 In the case reported by Dr. J. J. Reese, already cited, in 
 which about six grains of the poison had been taken and life 
 was prolonged for six hours, separate analyses, made eight 
 weeks afte;r death, of the contents of the stomach, of the con- 
 tents of the small intestines, and of the tissues of the stomach 
 and intestines, failed to reveal the presence of a trace of strych- 
 nine, either by the taste of the final extract or by the color 
 test. From the quantity of strychnine taken in this instance, 
 and the fact that there seems to have been no vomiting, it was 
 one apparently favorable for the recovery of the poison. Since 
 the tissues were in a good state of preservation at the time of 
 the examination, it can not reasonably be supposed that the 
 poison had undergone decomposition in the dead body. Dr. 
 Reese attributed the failure to the fact, that just before death 
 the deceased had taken a quarter of a grain of morphine, 
 which, as we have already seen, has the property of disguising 
 the ordinary reaction of the color test. But, as the final ex- 
 tracts were obtained through the agency of ether, in which 
 morphine is almost wholly insoluble, especially in the presence 
 of a free alkali, this explanation can hardly be admitted; more- 
 over, morphine has not the property of concealing the intensely 
 bitter taste of strychnine. 
 
 In regard to the efi^ects of decomposition, experiments indi- 
 cate that strychnine may be kept in contact with decomposing 
 animal matter, for at least several months, without itself under- 
 going any change. It would, however, be an error to suppose 
 that the alkaloid could be recovered, under these conditions, 
 after as long periods as some of the mineral poisons. In a case 
 of fatal poisoning by strychnine reported by Dr. A. A. Hayes, 
 of Boston, he recovered over half a grain of the pure crystal- 
 lised alkaloid, from the fourth part of the contents of the 
 
BRUCINE. 593 
 
 stomach, two weeks after death. (Boston Med. and Surg. Jour., 
 March, 1861, p. 133.) At the trial of Mary Freet, charged 
 with the murder of her husband by strychnine, it was alleged, 
 that a few weeks prior to the administration of the fatal dose, 
 the defendant prepared a bowl of mush and milk for the de- 
 ceased, and that he complained of its having a bitter taste and 
 threw the contents of the bowl into the yard; and that after- 
 wards a cat having eaten the mush very suddenly died. A 
 chemical examination of the contents of the stomach of the 
 animal two months after death, the body having part of the 
 time been exposed in a common alley, clearly revealed the 
 presence of strychnine. 
 
 Quantitative Analysis. — The quantity of strychnine pres- 
 ent in a pure aqueous solution of any of its salts, may be 
 estimated, with sufficient accuracy for ordinary purposes, by 
 treating the somewhat concentrated solution with slight excess 
 of caustic potash, and allowing the mixture to stand in a cool 
 place for from twelve to twenty-four hours, when the deposit 
 will have assumed the crystalline form. The precipitate is 
 then collected on a small equipoised filter, washed with a small 
 quantity of cold water, dried on a water-bath, and weighed. 
 Since strychnine is not wholly insoluble in water, even in the 
 presence of a free alkali, a minute portion of the alkaloid will 
 remain in the alkaline liquid. The quantity, however, that 
 may thus escape precipitation, will rarely exceed the 10,000th 
 part by weight of the fluid present. If on extracting the alka- 
 loid from its aqueous solution by means of chloroform or ether, 
 it is left, on evaporation of the liquid, in its pure state, it may, 
 of course, be at once weighed. One hundred parts by weight 
 of the alkaloid correspond to about 133 parts of the pure crys- 
 tallised sulphate, 118 of the acetate, or about 120 parts of 
 crystallised chloride of strychnine. 
 
 III. Beucine. 
 
 History. — Brucine, or brucia, occurs in most if not all the 
 Strychnos plants in which strychnine is found. It was first 
 
 38 
 
594 BRUCINE. 
 
 discovered, in 1819, by Pelletier and Caventou, in what was 
 formerly known as false Angustura bark, but which has since 
 been shown to be nothing else than the bark of the nux vomica 
 tree. It occurs both in the bark and seed of this tree; in the 
 bark — which contains less strychnine and more brucine than 
 the seed — it is said to be in combination with gallic acid, while 
 in the seed it is believed to be combined with strychnic acid. 
 The composition of the anhydrous alkaloid, according to Reg- 
 nault, is C^HjeNjOg. 
 
 Preparation. — Brucine may be obtained from the bark of 
 nux vomica, in a manner similar to that by which strychnine 
 is obtained from the seed, except that the alcoholic extract 
 obtained from the precipitate produced by lime, is treated with 
 oxalic acid, and subsequently with a mi&ture of alcohol and 
 ether, which dissolves the coloring matter, while the oxalate 
 of brucia remains undissolved. This salt is then decomposed 
 by magnesia, and the liberated brucine dissolved in alcohol, 
 which on spontaneous evaporation leaves the alkaloid in its 
 crystalline state. (U. S. Dispensatory, 1865, p. 563.) 
 
 Physiological Effects. — The effects of brucine on the animal 
 economy are precisely the same in kind as those of strychnine; 
 but it is less energetic in its action than the latter alkaloid, 
 having only about one-twelfth the power of that substance. 
 Dr. Christison cites two instances of poisoning by this sub- 
 stance; and Professor Casper relates three cases in which death 
 resulted from the taking of a mixture of arsenic and brucine 
 (Forensic Medicine, vol. ii, p. 102). The ordinary medicinal 
 dose of brucine is from half a grain to one grain, repeated two 
 or three times a day. 
 
 General Chemical Nature. — Brucine is a white, odorless 
 solid, having an intensely bitter taste, very similar to that of 
 strychnine. In its pure state, it is readily crystallisable, form- 
 ing beautiful groups of very delicate, transparent needles ; when 
 the crystals are only slowly produced, they usually appear in 
 the form of bold, colorless, four-sided prisms: the crystals con- 
 tain eight equivalents, or about 15*45 per cent, of their weight, 
 of water of crystallisation. When moderately heated, the crys- 
 tals fuse and become anhydrous; and at a higher temperature. 
 
SPECIAL CHEMICAL PROPERTIES. 595 
 
 the residue takes fire and burns with a dense smoky flame. 
 Brucine is unacted upon by the fixed caustic alkalies, but it is 
 readily decomposed by concentrated nitric acid. 
 
 The salts of brucine are colorless, except when they contain 
 a colored acid, and are, for the most part, easily crystallisable. 
 They have the bitter taste of the pure alkaloid, and are readily 
 decomposed by the caustic alkalies, with the elimination of the 
 brucine. In regard to its basic properties, brucine is somewhat 
 inferior to strychnine, it being displaced from its saline combi- 
 nations by that base. 
 
 Solubility. — When excess of pure powdered brucine is fre- 
 quently agitated with pure water, at the ordinary temperature 
 for twenty-four hours, one part of the crystallised alkaloid dis- 
 solves in 900 parts of the liquid : this corresponds to one part 
 of the anhydrous alkaloid in about 1,050 parts of the menstruum. 
 It is much more soluble in hot water, from which, however, the 
 greater part of the excess separates as the solution cools. Its 
 solubility in this liquid is somewhat increased by the presence 
 of foreign organic matter. 
 
 Absolute ether, when frequently agitated for several hours 
 at the ordinary te.mperature with excess of the powdered alka- 
 loid, dissolves one part of the anhydrous base in 440 parts of 
 the liquid. Chloroform readily dissolves the alkaloid in nearly 
 every proportion. It is thus obvious that this liquid is better 
 adapted than ether for the separation of the alkaloid from alka- 
 line aqueous mixtures. The alkaloid is also readily soluble in 
 nearly every proportion in absolute alcohol. But it is insoluble 
 in the fixed caustic alkalies ; and only sparingly soluble in large 
 excess of ammonia. Most of the salts of brucine are freely sol- 
 uble in water and in alcohol. 
 
 Special Chemical Peoperties. — Concentrated sulphuric 
 acid dissolves brucine and its salts with the production of a 
 faint rose-red color. If the acid contains nitric acid — as is fre- 
 quently the case — the alkaloid dissolves to a deep red solution. 
 If a small crystal of bichromale of potash be stirred in the sul- 
 phuric acid solution, the liquid acquires an orange or brownish- 
 orange color, which slowly changes to a greenish hue, due to 
 the separation of oxide of chromium. This reaction at once 
 
596 BRUCINE. 
 
 distinguislies brucine from strychnine. Concentrated nitric acid 
 dissolves the alkaloid, as well as its salts, to a deep red solu- 
 tion, the color of which slowly fades to yellow. The alkaloid 
 is readily soluble in concentrated hydrochloric acid, without 
 change of color. 
 
 In the following examination of the reactions of solutions of 
 brucine, the pure crystallised alkaloid was dissolved, by the aid 
 of just sufficient acetic or sulphuric acid, in pure water. The 
 fractions employed, indicate the fractional part of a grain of the 
 crystallised alkaloid in solution in one grain of water; and the 
 results, unless otherwise indicated, refer to the behavior of one 
 grain of the solution. One grain of pure crystallised brucine 
 corresponds to 0-845 of a grain of the anhydrous alkaloid. 
 
 1. Fotash and Ammonia. 
 
 The caustic alkalies produce in concentrated solutions of 
 salts of brucine a white amorphous precipitate of the pure an- 
 hydrous alkaloid, which after a little time, by the assimilation 
 of water, assumes the crystalline form. The precipitate is 
 readily soluble in free acids, even in acetic acid ; but it is insol- 
 uble in large excess of either potash or soda. In its amorphous 
 state, the precipitate is rather freely soluble in large excess of 
 ammonia; but when it has assumed the crystalline form, it is 
 only very sparingly soluble in that liquid. 
 
 1. ro^ grain of brucine, in one grain of water, yields with 
 
 either of the fixed alkalies an immediate amorphous pre- 
 cipitate, which in a very little time gives rise to very 
 beautiful groups of exceedingly delicate crystalline needles, 
 Plate XI, fig. 5 ; and soon the mixture becomes converted 
 into a nearly soKd mass of crystals. Ammonia produces 
 a similar precipitate, but it does not usually appear until 
 after some little time ; it then separates in the crystalline 
 form. If large excess of ammonia be added, the precipi- 
 tate may fail to appear, even after several hours. 
 
 2. iw grain, yields with a fixed alkali, an immediate cloudi- 
 
 ness, and soon a very good crystalline precipitate. The 
 formation of the precipitate is much facilitated by stirring 
 
NITRIC ACID AND CHLORIDE OF TIN TEST. 597 
 
 the mixture. Very similar results may be obtained by 
 ammonia, providing it be added in very minute quantity. 
 Solutions of salts of brucine but little more dilute than the 
 last mentioned, fail to yield a precipitate by either of the fore- 
 going reagents. 
 
 The alkaline carbonates behave with solutions of salts of 
 brucine, much in the same manner as the free alkalies. The 
 true nature of the precipitate produced by either of the rea- 
 gents now mentioned, may be confirmed by either of the two 
 next-mentioned tests. 
 
 2. Nitric Acid and Chloride of Tin. 
 
 If a few crystals of brucine or of any of its colorless salts, 
 in the dry state, be treated with a drop of concentrated nitric 
 acid, they immediately assume a deep blood-red color, and 
 quickly dissolve to a solution of the same hue ; on heating this 
 solution, its color is changed to orange-yellow or yellow. If, 
 when the solution has cooled, a drop of a solution of protochlo- 
 ride of tin be then added, the mixture immediately acquires a 
 beautiful purple color, which is discharged by large excess of 
 either nitric acid or of the tin compound, as also by sulphurous 
 acid gas. The red color of nitric acid solutions of brucine con- 
 taining a quite notable quantity of the alkaloid, is changed to 
 a faint purple on the addition of the tin solution alone, without 
 the application of heat : but the intensity of the color, as thus 
 obtained, is much inferior to that obtained from the brucine 
 solution after it has been heated ; and if only a minute quantity 
 of the alkaloid be present, without the application of heat, the 
 purple color entirely fails to appear. 
 
 The following quantities of brucine were obtained by evap- 
 orating one grain of the corresponding solution of the acetate to 
 dryness on a water-bath. 
 
 1. Yoo" grain of brucine, dissolves in a drop of the acid to a 
 
 deep red solution, which, when heated and allowed to cool, 
 acquires an intense purple color, on the addition of the tin 
 compound, , 
 
 2. rxo? grain : the drop of acid acquires a very satisfactory 
 
598 BRUCINE. 
 
 red color, which upon the addition of the tin salt, after the 
 solution has been heated, is changed to a beautiful lilac. 
 
 3. 10.000 grain : on the addition of a very small drop of the 
 
 acid, the deposit assumes a very decided red color, and 
 dissolves to a faint red solution; the tin salt produces a 
 quite distinct lilac coloration. To obtain the latter color, 
 the acid and tin compound must be well apportioned, 
 otherwise the reaction may entirely fail to manifest itself. 
 This is about the limit of the tin reaction. 
 
 4. 5 ,0 o "o grain, when moistened with a minute trace of the 
 
 acid, assumes a quite perceptible red color; if this mix- 
 ture be evaporated to dryness, on a water-bath, it leaves 
 a very satisfactory red deposit. 
 5- roo%oo grain, when treated as under 4, leaves a quite dis- 
 tinct red residue. 
 These reactions of nitric acid and chloride of tin, when 
 taken in connection, are quite characteristic of brucine; and at 
 the same time, as we have just seen, they are exceedingly 
 delicate. In these respects, this test bears much the same 
 relation to brucine that the color test does to strychnine. Nitric 
 acid also produces a red color with morphine and with several 
 other substances, besides brucine; but the subsequent addition 
 of chloride of tin, fails to produce, with any of these fallacious 
 solutions, a purple coloration. The red color of the acid solu- 
 tion of morphine, is but little affected by the tin compound, at 
 most being changed to yellow; when the acid solution has been 
 heated and allowed to cool, the tin salt produces no visible 
 change. 
 
 3. Sulphuric Acid and Nitrate of Potash. 
 
 Brucine and its salts, as already pointed out, dissolve in 
 concentrated sulphuric acid with the production of a rose-red 
 color. If a crystal of nitrate of potash be stirred in a solution 
 of this kind, the mixture acquires a deep orange-red color, due 
 to the action of the nitric acid of the nitre. This test, there- 
 fore, is very similar in its action to the one just considered. 
 1. Y^u grain of brucine, when treated with a small drop of the 
 concentrated acid, dissolves to a solution having a faint 
 
SULPHOCYANIDE OF POTASSIUM TEST. 599 
 
 rose color, which on the addition of a small crystal of 
 nitre, is changed to deep orange-red. 
 2. 1,000 grain: on the addition of the acid, the deposit assumes 
 a quite perceptible rose-red color, and dissolves to a color- 
 less solution, which on the addition of the nitre acquires a 
 beautiful orange color. 
 3' 10,000 grain: the acid dissolves the deposit with little or no 
 change of color; but the solution, when treated with the 
 potash salt, acquires an orange color, which soon changes 
 to yellow. 
 4. 2 5.oo 'o grain: when the acid solution is treated with the 
 nitre, it yields only a faintly yellow coloration. But if a 
 small crystal of nitre be moistened with the acid and then 
 stirred over the dry brucine deposit, the crystal acquires 
 a distinct orange color. 
 The production of these colors is quite peculiar to brucine. 
 Sulphuric acid solutions of narcotine, opianyl, and morphine, 
 when treated with nitrate of potash, yield colors somewhat 
 similar to that produced from brucine; but neither of these 
 substances dissolves in the acid with the production of a rose- 
 red color. 
 
 4. Sulphocyanide of Potassium. 
 
 This reagent throws down from quite concentrated solutions' 
 of salts of brucine a white precipitate of the sulphocyanide of 
 brucine, which is insoluble in acetic acid. As produced from 
 very concentrated solutions, the precipitate is in the amorphous 
 form, but it soon becomes more or less crystalline. From some- 
 what more dilute solutions, the precipitate does not appear until 
 after some time, and it then separates in the form of small 
 granules. The formation of the precipitate from solutions of 
 this kind, is much facilitated by stirring the mixture with a 
 glass rod. 
 
 One grain of a 100th solution of the alkaloid, yields no 
 immediate precipitate, but in a few moments, comparatively 
 large groups of minute granules appear, and after a few min- 
 utes there is a quite good deposit of these groups, with occa- 
 sionally, small transparent crystalline plates, Plate XI, fig. 6. 
 
600 BRUCINE. 
 
 A similar quantity of a 500th solution, fails to yield a precip- 
 itate, even when the mixture is allowed to stand for some hours. 
 
 5. Bichromate of Potash. 
 
 Bichromate of potash throws down from solutions of salts of 
 brucine, even when highly diluted, a yellow precipitate of chro- 
 mate of hrucia, which is insoluble in acetic acid. The precip- 
 itate is readily soluble, with the production of a deep red color, 
 in concentrated nitric acid, and in sulphuric acid, with the 
 production of a reddish-brown color. 
 
 !• TS~o grain of brucine, in one grain of water, yields a quite 
 copious amorphous precipitate, which in a few moments 
 becomes converted into crystalline groups of the forms 
 illustrated in Plate XII, fig. 1. 
 
 2. i.Joo grain: if the mixture be stirred, it immediately yields 
 
 streaks of granules and small crystals, along the path of 
 the rod, and in a little time, there is a quite copious crys- 
 talline deposit. 
 
 3. 5",wo grain, yields after a little time, especially if the mix- 
 
 ture has been stirred, a quite satisfactory crystalline , pre- 
 cipitate. 
 
 4. 10,0 grain: after several minutes, a quite distinct precip- 
 
 itate, and after about half an hour, a very satisfactory 
 deposit of crystalline needles. 
 
 The crystalline form of the precipitate, as produced from 
 somewhat strong solutions of the alkaloid, together with the 
 subsequent reaction of nitric acid, serve to distinguish the 
 chromate of brucia from all other precipitates produced by 
 this reagent. 
 
 Protochromate of potash produces in solutions of the alkaloid, 
 results very similar to those occasioned by the bichromate, only 
 that the reaction is not quite so delicate. 
 
 6. Bichloride of Platinum. 
 
 Solutions of salts of brucine yield with bichloride of plati- 
 num, a yellow precipitate of the double chloride of platinum 
 
CHLORIDE OF GOLD TEST. 601 
 
 and brucine, which is unchanged by acetic acid, but readily 
 
 decomposed by the caustic alkalies. 
 
 !• Too" grain of brucine, yields a very copious deposit, which 
 almost immediately becomes a mass of irregular crystalline 
 needles. The precipitate is slowly soluble in nitric acid, 
 yielding an orange-red solution. 
 
 2. 1,0 grain: an immediate, light-yellow, crystalline precipi- 
 
 tate, which in a Kttle time, becomes converted into irregu- 
 lar needles, Plate XII, fig. 2. 
 
 3. s.doo grain: very soon crystals appear, and after a little 
 
 time, there is a quite good crystalline deposit. 
 
 4. 10,0 grain: if the mixture be stirred, it immediately yields 
 
 crystalline streaks, and very soon a quite fair deposit. 
 
 grain: after a few minutes, if the mixture has been 
 
 stirred, crystalline needles appear, and after a little time, 
 
 there is a quite satisfactory deposit. 
 This reagent also produces yellow crystalline precipitates 
 with various other substances, but the form of the brucine 
 deposit is somewhat peculiar. 
 
 7. TercMoride of Gold. 
 
 This reagent produces in solutions of salts of brucine a 
 yellow amorphous precipitate, which in a little time acquires- 
 a flesh color. The precipitate is but sparingly soluble in 
 acetic acid; the caustic alkalies cause it to quickly assume 
 a dark color. 
 
 1. Yo^ grain of brucine, in one grain of water, yields a very 
 
 copious deposit. 
 
 2. 1,00 grain, yields a greenish-yellow precipitate, which soon 
 
 becomes yellow; the deposit is readily soluble to a clear 
 solution in caustic potash. 
 
 3. 10,0 grain: a quite good, yellowish deposit. 
 
 4. 2 5.000 grain, yields, in a very little time, a distinct turbidity, 
 
 and after a few minutes, a quite satisfactory precipitate. 
 
 5. 5 ,0 o TJ grain: after some minutes, a quite distinct deposit. 
 All these precipitates remain amorphous. The reactions of 
 
 this reagent are common to a large class of substances. 
 
602 BRUCINE. 
 
 8. Carhazotic Acid. 
 
 An alcoholic solution of cai'bazotic acid throws down from 
 aqueous solutions of salts of brucine a yellow precipitate, of the 
 carbazotate of brucia, which is but sparingly soluble in large 
 excess of acetic acid. 
 
 1. xoo" grain of brucine, yields a very copious precipitate, 
 
 which after a time becomes, in part at least, crystalline. 
 The formation of these crystals is readily prevented by 
 the presence of foreign organic matter. 
 
 2. r.'ToT) grain, yields a very good precipitate, which after a 
 
 time is converted into groups of aggregated granules, 
 similar to those produced by sulphocyanide of potassium 
 (Plate XI, fig. 6). 
 
 3. lu.ouo grain, yields, after several minutes, especially if the 
 
 mixture has been stirred, a quite distinct precipitate. 
 The reaction of this reagent is valuable only in so far as it 
 confirms the reactions of the other tests for brucine. 
 
 9. Ferricyanide of Foiassium, 
 
 Concentrated neutral solutions of salts of brucine, when 
 treated with this reagent, yield a light-yellow crystalline pre- 
 cipitate, which is readily soluble in the mineral acids. The 
 formation of the precipitate is readily prevented by the pres- 
 ence of a free acid, even of acetic acid, but after the crystals 
 have formed they are only very sparingly soluble in large 
 excess of acetic acid. 
 
 !• TTo grain of brucine, yields an immediate precipitate, and 
 in a few moments, there is a very copious deposit of crys- 
 tals, grouped in various and most beautiful forms, Plate 
 XII, fig. 3. These crystalline groups are, perhaps, the 
 most brilliant polariscope objects yet known. The produc- 
 tion of these crystals is quite characteristic of brucine. 
 
 2. woT grain: after stirring the mixture, it yields, in. a very 
 
 little time, a copious granular deposit. 
 
 3. Troon grain: after some time, a slight turbidity. 
 
IODINE AND BROMINE TESTS. 603 
 
 Ferrocyanide of potassium produces no precipitate with a 
 100th solution of brucine, even if the mixture be allowed to 
 stand for some time. 
 
 10. Iodine in Iodide of Potassium. 
 
 A solution of iodine in iodide of potassium produces in 
 normal solutions of salts of brucine, even when very highly 
 diluted, an orange-brown, amorphous precipitate, which is insol- 
 uble in acetic acid. 
 
 !• Too' grain of brucine, yields a very copious deposit, which 
 is decomposed by large excess of potash, with the produc- 
 tion of a dirty-white precipitate. 
 
 2. i,Joo grain: much the same results as 1. 
 
 3. 10,0 grain, yields a quite good, brownish precipitate, which 
 
 is soluble to a clear solution in potash. 
 
 4. 5 0,0 grain, yields a yellowish deposit. 
 
 5. 10 0% grain: a very distinct, dirty-yellowish turbidity. 
 
 6. 5 0^00 grain, yields a perceptible cloudiness. 
 
 It need hardly be remarked that, this reagent produces 
 similar precipitates in solutions of most of the alkaloids and of 
 various other organic substances. 
 
 11. Bromine in Bromohydric Acid. 
 
 A strong aqueous solution of bromohydric acid saturated 
 with bromine produces in solutions of salts of brucine, when 
 not too dilute, a deep-brown amorphous precipitate, which after 
 a time dissolves, but is reproduced upon further addition of the 
 reagent. The precipitate is soluble in acids, even acetic acid, 
 and in potash. 
 
 1. xtTo grain of brucine, yields a very copious, deep-brown 
 
 deposit, which soon acquires a yellow color, then a bright 
 yellow, and after some minutes dissolves. 
 
 2. 1,000 grain: much the same results as 1. 
 
 3. 10,000 grain, yields a yellowish precipitate, which after a 
 
 time disappears, and is not reproduced upon further addi- 
 tion of the reagent. 
 
604 BRUCINE. 
 
 4. 2 ,0 00 grain, yields a greenish-yellow deposit, whicli soon 
 dissolves. 
 The brown color of the brucine deposit distinguishes it from 
 the precipitates produced by this reagent with other ' alkaloids. 
 
 Other Reactions. — Corrosive sublimate throws down from a 
 100th solution of salts of brucine a quite good, white, amorph- 
 ous precipitate, which soon becomes granular; with solutions 
 but little more dilute than this, the reagent fails to produce a 
 precipitate. Iodide of potassium produces in a 100th solution 
 of the alkaloid no immediate precipitate, but after a time there 
 is a quite good deposit of rough needles and crystalline plates. 
 Tannic acid throws down from even highly diluted solutions of 
 the alkaloid a dirty-white, amorphous precipitate, which is solu- 
 ble in acetic acid. 
 
 Chlorine gas passed into concentrated solutions of salts of 
 brucine produces at first a yellow, then a red color, which is 
 discharged by excess of the gas. Upon the subsequent addition 
 of ammonia, the liquid acquires a light brown color. These 
 reactions manifest themselves only in very strong solutions of 
 salts of the alkaloid. 
 
 Administered to frogs, brucine produces violent tetanic con- 
 vulsions, similar to those occasioned by strychnine, but their 
 production requires relatively a much larger quantity of the 
 former than of the latter alkaloid. 
 
 Separation from Organic Mixtures. 
 
 Brucine may be separated from organic mixtures in the 
 same manner as heretofore directed for the recovery of strych- 
 nine. When the analysis furnishes only a small residue for the 
 application of the chemical tests, a portion of it should first be 
 examined by the nitric acid and chloride of tin test. If this 
 yields a positive reaction, it fully establishes the presence of 
 the alkaloid. When, however, sufficient material is at hand, the . 
 reaction of this test should be confirmed by some of the other 
 tests. Should the nitric acid and tin test fail, it is quite certain 
 that, under similar conditions, the other tests would also fail. 
 
RECOVERY FROM ORGANIC MIXTURES. 605 
 
 One grain of brucine in solution was given to a recently 
 fed cat; thirty minutes afterwards, the animal was seized with 
 violent tetanic convulsions and died during the paroxysm. On 
 now applying the method directed for the recovery of strych- 
 nine, to the examination of the contents of the stomach of the 
 animal, a very notable quantity of pure crystallised brucine was 
 recovered. And six fluid drachms of blood, taken from the 
 same animal and treated after the strychnine method, gave, 
 when the first chloroform residue was examined by the tin test, 
 perfectly unequivocal evidence of the presence of brucine. 
 
606 ACONITINE. 
 
 OHAPTEE IT. 
 
 ACONITINE, ATROPINE, DATURINE. 
 
 Section I. — Aconitine. (Aconite.) 
 
 History. — Aconitine is the name applied to the active prin- 
 ciple, or alkaloid, of Aconite, , Monkshood, or Wolfsbane, the 
 Aconitum napellus of botanists. It exists in all parts of the 
 plant, but in the greatest proportion in the root, and is said to 
 be combined with a peculiar organic acid, the aconitic. The 
 dried root is usually estimated to contain from O'l to 0'2 per 
 cent, of the alkaloid. It is also found in several other species 
 of this genus of plants ; the Aconitum ferox is generally con- 
 sidered to be the most poisonous of the species. Aconitine 
 was first obtained, although in an impure state, by Greiger 
 and Hesse, in 1832. Its composition, according to Planta, is 
 C60H47NOH. (Chemical Gazette, 1850, p. 352.) In its pure 
 state, this substance is perhaps the most powerful poison yet 
 known. According to Hubschmann, aconite contains another 
 alkaloidal principle, which he has described under the name 
 of napellina. 
 
 Preparation. — Various methods have been proposed for the 
 preparation of aconitine. The following process has recently 
 been advised by MM. Liegeois and Hottot. The bruised root 
 of the plant is digested for eight days with rectified spirit, 
 slightly acidulated with sulphuric acid ; the alcoholic liquid is 
 then pressed out, and the alcohol removed by distillation. The 
 residue is allowed to cool, and any solid resinous matter that 
 separates removed. The liquid is now concentrated to the con- 
 sistency of a syrup, then treated with two or three volumes of 
 pure water, and the mixture allowed to repose, as long as any 
 green oil collects upon its surface ; this is then removed, the 
 
PREPARATION. 607 
 
 last traces being separated by a filter previously moistened with 
 water. The liquid is next treated with slight excess of hydrate 
 of magnesia, and repeatedly agitated with pure ether, which 
 will extract the alkaloid. The united ethereal extracts are 
 evaporated to dryness, and the residue dissolved in water by 
 the aid of slight excess of sulphuric acid. The alkaloid is then 
 precipitated from the filtered solution by slight excess of am- 
 monia, and further purified by repeated solution in water acidu- 
 lated with sulphuric acid and re-precipitation by ammonia. The 
 final precipitate is washed with cold water, as long as any odor 
 of ammonia is present, then dried at a low temperature. 
 
 Another method, for the preparation of the alkaloid, has still 
 more recently been proposed by Mr. T. B. Groves. Five parts 
 of the coarsely-powdered root are' macerated for about seven 
 days with one part of methylated spirit, strongly acidulated 
 with hydrochloric acid. The liquid portion is then expressed 
 from the solid matters, treated with a little water, and the spirit 
 separated by distillation. When the residue has cooled, any 
 oily matters that have separated are removed by a filter. The 
 clear filtrate is treated with slight excess of a strong solution of 
 iodohydrargyrate of potassium, and the mixture moderately 
 heated, with constant stirring, until the precipitate has com- 
 pletely separated. This is collected, washed, and dissolved in 
 hot methylated spirit, and the iodine precipitated from the warm 
 liquid by slight excess of a hot aqueous solution of nitrate of 
 silver. The iodide of silver thus produced, is separated by a 
 filter, and the filtrate treated with sulphuretted hydrogen gas, 
 for the purpose of removing any nitrate of mercury present. 
 The liquid is again filtered, then treated with slight excess of 
 carbonate of potash, which will precipitate the alkaloid. This 
 is extracted by repeatedly agitating the mixture with ether, and 
 the united ethereal extracts are evaporated to dryness. The 
 residue, which consists of nearly pure aconitine, is dissolved in 
 water acidulated with nitric acid, the solution filtered, and set 
 aside to crystallise. The author of this method states that by 
 it, the alkaloid may readily be obtained in its crystalline state, 
 in the form of nitrate. (Amer. Jour. Pharmacy, Nov., 1866, 
 p. 518.) 
 
608 ACONITINE. 
 
 Poisoning by aconitine in its pure state, has been of very- 
 rare occurrence ; but there have been numerous instances of 
 poisoning by the root, leaves, and some of the preparations of 
 aconite, chiefly, however, as the result of accident. The root 
 has not unfrequently been mistaken for horseradish. The prin- 
 cipal pharmaceutical preparations of aconite are the tinctures 
 of the root and of the leaves, and the alcoholic extract. Each 
 of these preparations is subject to considerable variation in 
 strength, depending both on the formula followed for its prepa- 
 ration and the quality of the material employed. The medicinal 
 dose of the pure alkaloid is said to be about the l-130th part of 
 a grain ; it is rarely prescribed in this form, and requires great 
 caution in its administration. 
 
 Symptoms. — The eflfects of poisonous doses of aconite are 
 in some respects quite peculiar. At first there is a sense of 
 tingling and numbness in the lips, mouth, and throat, with a 
 feeling of warmth or burning in the stomach. These effects 
 are succeeded by tingling in various parts of the body, pain in 
 the abdomen, headache, vertigo, and nausea, frequently attended 
 by vomiting, and sometimes purging; there is also, diminished 
 sensibility of the skin, constriction in the throat, frothing at the 
 mouth, partial or entire loss of voice, impaired vision, ringing 
 in the ears, a feeling of tightness in various parts of the body, 
 cold perspirations, muscular tremors, and great prostration of 
 strength. The pulse becomes small and feeble, or altogether 
 imperceptible ; the countenance pale and sunken ; the extremi- 
 ties cold and clammy : the pupils are usually dilated, but not 
 unfrequently contracted. Death usually takes place by syncope. 
 In some instances, death is preceded by delirium and convul- 
 sions. In fifty-three cases of aconite poisoning collected by 
 Dr. Tucker, of New York, and cited by Wharton and Stille, 
 general convulsions occurred only in seven. 
 
 The symptoms usually manifest themselves within a few 
 minutes after the poison has been taken ; but they have been 
 delayed for more than an hour. In a case quoted by Dr. Beck 
 (Med. Jur., vol. ii, p. 890), in which a man had eaten some 
 salad containing, by mistake, a quantity of aconite, the patient 
 immediately experienced a burning heat in the tongue and gums. 
 
PHYSIOLOGICAL EFFECTS. 609 
 
 and. irritation in the cheeks. This tingling sensation extended 
 over the whole body, and was accompanied by muscular twitch- 
 ings. The eyes and teeth became fixed ; the extremities cold 
 and bathed with perspiration ; the pulse imperceptible, and the 
 breathing so short as scarcely to be distinguishable. Under the 
 active use of remedies, the patient gradually recovered. 
 
 In a case reported by Dr. Gray, in which a healthy boy 
 fourteen years of age, was given by mistake a tablespoonful of 
 the tincture of aconite, the following symptoms were observed. 
 In about five minutes the patient began to experience the effects 
 of the poison, and in twenty minutes the pupils were slightly 
 dilated and nearly insensible to light ; the countenance was pale, 
 and he moved with difficulty ; his head felt heavy, and there 
 was frequent retching, with the discharge of small quantities of 
 mucus. An emetic of sulphate of zinc was immediately admin- 
 istered, and quickly produced copious vomiting. The patient 
 now experienced a sense of intense burning in the stomach and 
 oesophagus, and was greatly prostrated; the pulse became slow, 
 the extremities cold, the pupils widely dilated, and he com- 
 plained of great numbness of his head, but not of any other 
 part of the body, and lost the power of sight. Under the use 
 of a laxative enema, and external and internal stimulants, there 
 was a slight amelioration of the symptoms for about half an 
 hour ; but the collapse again returned, the respiration became 
 slow and difficult, the muscles of the head and trunk rigid, the 
 surface cold, deglutition impossible, and death supervened sud- 
 denly, under full consciousness, two hours after the poison had 
 been taken. (New York Jour, of Med., Nov., 1848, p. 336.) 
 
 In another case, a healthy man ate some greens consisting 
 for the most part of the root of aconite. Almost immediately 
 afterwards he complained of a feeling as if he could not draw 
 in his tongue, and various hallucinations of sight. These symp- 
 toms were soon succeeded by vomiting, involuntary stools and 
 passage of urine, a peculiar sensation in the extremities, a feel- 
 ing of pricking in the whole body, and fainting, followed by 
 death. (Reil's Monograph upon Aconite, p. 46.) 
 
 The following case of recovery occurred in the practice of 
 Dr. McCready, of New York. A healthy Irish woman, about 
 
 39 
 
610 ACONITINE. 
 
 twenty-five years of age, swallowed a tablespoonful of a satu- 
 rated tincture of aconite, mistaking it for brandy. When seen 
 an hour afterwards her countenance was flushed, the pupils 
 dilated, though sensible to light ; the pulse frequent, soft and 
 weak, the beat being sometimes so feeble as to be almost imper- 
 ceptible. She complained of a feeling of fullness about her 
 limbs, as if they were about to burst, accompanied by a sensa- 
 tion of numbness and pricking over the whole surface ; and 
 there were numbness and tingling of the tongue, and a strange 
 sensation about the throat. There was no sickness at the stom- 
 ach, and the head was perfectly clear. An emetic of sulphate 
 of zinc and ipecacuanha was administered arid produced' copious 
 vomiting. Half an hour afterwards, the pulse was. still frequent 
 and feeble, the beats continuing irregular in force. She com- 
 plained of feeling weak, but in other respects was about the 
 same as when first seen. Three hours later, the dilatation of 
 the pupils had passed away, but the numbness and. tingling 
 remained. The next day she was almost in her usual health. 
 (Amer. Jour. Med. Sci., Jan., 1852, p. 268.) 
 
 Period when Fatal. — In fatal poisoning by aconite or any of 
 its preparations, death usually occurs in from two to six hours 
 after the poison has been taken ; but considerable variation has 
 been observed in this respect. A case is reported in which 
 one drachm of the tincture, taken by an adult, proved fatal in 
 one hour and a half, the patient being strongly convulsed just 
 before death. In another instance, a child aged two years and 
 seven months, having eaten an unknown quantity of the fresh 
 leaves of aconite, was soon seized with violent symptoms, but 
 death did not occur until after the lapse of about twenty hours. 
 (Lancet, London, June, 1856,_ p. 715.) In this case, shortly 
 after the symptoms manifested themselves there was violent 
 vomiting, which brought away pieces of the leaves : no vege- 
 table matter was found in the stomach after death. 
 
 Fatal Quantity. — Since the preparations of aconite are sub- 
 ject to great variation in strength, similar quantities of the same 
 form of preparation have given rise to very different results. 
 Thus Dr. Fleming mentions an instance where two grains of 
 the alcoholic extract occasioned alarming effects, and another in 
 
FATAL QUANTITY. 611 
 
 which four grains proved fatal ; whilst Dr. Christison relates an 
 instance in which he gave six grains of a carefully prepared 
 alcoholic extract, to a woman suffering from rheumatism, with- 
 out being able to observe any effect whatever. (On Poisons, 
 p. 667.) In a case reported by Dr. Easton, twenty-five minims 
 of a tincture of the root of aconite, with twenty minims of tinc- 
 ture of belladonna, caused the death of a* healthy young man, 
 within three hours ; and in another instance, twenty-five drops 
 of the tincture, prescribed through ignorance, proved fatal to a 
 man, in about four hours. (American Medical Monthly, March, 
 1854, p. 223.) Several instances are reported in which about 
 a drachm of the tincture destroyed life. 
 
 In a case communicated to Dr. Pereira, two doses of six 
 drops each of the tincture, taken at an interval of two hours, 
 by a young man aged twenty-one years, produced most alarming 
 symptoms. (Mat. Med., vol. ii, p. 1091.) We are acquainted 
 with an instance in which a very intelligent physician adminis- 
 tered to his wife a dose of five drops of Thayer's fluid extract 
 of the root of aconite. In from ten to fifteen minutes after- 
 wards she experienced a burning sensation in the throat and 
 great numbness in the arms ; these effects were soon followed 
 by tingling in the surface of the whole body, difficulty of breath- 
 ing, impending suffocation, dimness of vision, and alarming pros- 
 tration, which continued for about two hours : she then rapidly 
 recovered. 
 
 Eecovery has not • unfrequently taken place after compara- 
 tively large quantities of some of the preparations of aconite 
 were taken. In a case recently reported by Mr. Kay, a lady 
 took by mistake two' teaspoonfuls of the tincture, and entirely 
 recovered in eight hours afterwards. In this case the symp- 
 toms did not manifest themselves until an hour after the poison 
 had been taken. An emetic was then given, which quickly 
 operated. The patient then lost the use of her lower extremi- 
 ties ; the face had an anxious expression ; the forehead was 
 wrinkled and corrugated ; the pupils slightly dilated ; pulse 
 slow, feeble, and intermitting; the extremities cold, but the 
 intellect quite unaffected. She complained of a burning sensa- 
 tion in the throat, and a constriction at the chest ; and lost the 
 
612 ACONITINE. 
 
 sense of feeling in her legs, arms, and face. (Lancet, Reprint, 
 Oct., 1861, p. 273.) In another case, related by M. Devay, a 
 porter in a druggist's shop, swallowed by mistake nearly one 
 ounce and a half of an alcoholic solution of aconite, and although 
 he immediately experienced a sense of heat and constriction in 
 the throat and was soon seized with the most violent symptoms, 
 yet he was quite well three days afterwards. (Chemical Ga- 
 zette, vol. ii, p. 220.) 
 
 Aconitine in its pure state, as already mentioned, is one of 
 the most virulent poisons known. Dr. Headland considers that 
 one-tenth of a grain of the pure alkaloid would be sufficient to 
 destroy the life of a healthy adult man. And Dr. Pereira 
 mentions an instance in which one-fiftieth of a grain nearly 
 proved fatal to an elderly lady. (Mat. Med., ii, p. 1093.) A 
 most remarkable instance of recovery, in which a gentleman 
 had taken two grains and a half of aconitine, is related by Dr. 
 Golding Bird. It seems that almost immediately after taking 
 the poison the patient fell, and was seized with violent vomiting, 
 by which it is believed that most of the poison was ejected. 
 Some time after the occurrence, the patient was in a most fear- 
 ful state of collapse ; the surface cold and perspiring ; the action 
 of the heart scarcely perceptible, but the intellect was unim- 
 paired. The most prominent symptom, which continued for 
 some hours, was repeated and most violent convulsive vomiting. 
 On attempting to swallow any fluid the patient was seized with 
 violent spasms of the throat, somewhat similar to those observed 
 in hydrophobia. This latter symptom continued for several 
 hours, and it was not until about thirty hours after the poison 
 had been taken that the patient was considered convalescent. 
 (New York Journal of Medicine, March, 1848, p. 285.) 
 
 Treatment. — The first indication is to thoroughly evacuate 
 the contents of the stomach, either by an emetic or the use of 
 the stomach-pump. As an emetic sulphate of zinc is usually 
 preferred. Stimulants, such as ammonia and brandy, may often 
 be employed with great advantage ; and the use of stimulating 
 injections have been attended with good results. As an anti- 
 dote, the free administration of finely-powdered animal char- 
 coal, mixed with water, has been strongly recommended by Dr. 
 
PATHOLOGICAL EFFECTS. 613 
 
 Headland, and others. It is claimed that this substance will 
 unite with the poisonous alkaloid, and thus prevent its absorp- 
 tion into the system. The charcoal is then removed from the 
 stomach by an emetic. Vegetable infusions containing tannic 
 acid, and a solution of iodine in iodide of potassium, have also 
 been strongly advised, on the grounds that they form insoluble 
 compounds with the alkaloid. 
 
 From the apparent antagonism existing between the physio- 
 logical effects of aconite and those of nux vomica, these sub- 
 stances have been recommended as mutual antidotes. The fol- 
 lowing case, in which this remedy was employed, is reported 
 by Dr. Hanson. A boy, aged five years, swallowed a mixture 
 of tincture of aconite and simple syrup. When first seen by 
 Dr. Hanson, the patient was laboring under the usual symptoms 
 of aconite poisoning, in an, aggravated degree. Emetics and 
 tickling the fauces with a feather were resorted to, but without 
 producing vomiting, and the patient continued to sink. Half 
 an hour after the first dose of tartar emetic had been given, 
 three drops of the tincture of nux vomica were administered. 
 In a few minutes the action of the heart was increased in force, 
 and the respiration much improved. At the end of twenty 
 minutes, the dose of nux vomica was repeated. Vigorous vom- 
 iting now soon ensued, after which the patient rapidly recovered. 
 (Amer. Jour. Med. Sci., Jan., 1862, p. 285.) 
 
 Post-mortem Appearances. — The most common morbid ap- 
 pearances, in death from aconite, are an injected condition of 
 the blood-vessels of the brain and of its membranes, and con- 
 gestion of the lungs and liver, with more or less redness of the 
 mucous membrane of the stomach and intestines. The stomach 
 and small intestines are frequently found empty. The right 
 cavities of the heart usually contain more or less blood ; the 
 blood throughout the body is generally fluid and of a dark color. 
 It need hardly be remarked that none of these appearances are 
 peculiar to death from this substance. In two cases of fatal 
 poisoning by a tincture of the root of aconite, quoted by Dr. 
 Beck, the only morbid appearances observed on dissection were 
 gi-eat redness of the lining membrane of the stomach and small 
 intestines. 
 
614 ACONITINE. 
 
 In an instance quoted by Orfila (Toxicologie, ii, 443), in 
 which five persons swallowed each a glass of brandy in which 
 the root of aconite had been macerated, and three of them died, 
 death taking place in about two hours, the following appear- 
 ances were observed. The oesophagus, stomach, and intestines 
 were found much inflamed, and the blood-vessels, especially the 
 veins, of the digestive tube much injected. The mesentery was 
 also inflamed. The cavity of the peritoneum contained a large 
 quantity of yellowish serum. The lungs were dense, of a bluish 
 and violet hue, slightly crepitant, and gorged with blood. The 
 pericardium contained a large quantity of serum ; the heart and 
 large vessels presented nothing remarkable. The brain was 
 healthy, but its blood-vessels somewhat injected. 
 
 In the case of the child, already cited, in which the leaves 
 of aconite had been eaten and life was prolonged for about 
 twenty hours, the body presented the following appearances 
 sixty hours after death. The abdomen externally was much 
 discolored ; and patchy discolorations were visible on the thighs 
 and legs, but the spots were not so apparent as during life. 
 The stomach was highly inflamed throughout its whole extent ; 
 it contained a little fluid of a lightish-brown color, but no food, 
 nor any traces of leaves or other vegetable matter. Various 
 parts of the small intestines presented patches of intense inflam- 
 mation, in some places approaching to gangrene. The large 
 intestines presented nothing particular. The bladder was full 
 of urine ; the spleen somewhat congested. The pericardium 
 contained about half an ounce of bloody serum. The heart was 
 full of uncoagulated blood, and the blood throughout the body 
 was thin and fluid. The other parts of the body were nearly 
 or altogether normal'. 
 
 Chemical Propeeties. 
 
 In the Solid State. — Aconitine, in its pure state, is a white, 
 transparent, odorless solid, which until recently seems not to 
 have been obtained in the crystalline form. It has an acrid 
 taste, followed by a sense of tingling and numbness of the 
 tongue ; applied in the form of solution to the skin, "it causes a 
 
CHEMICAL PROPERTIES. 615 
 
 persistent feeling of heat and numbness. These effects are 
 produced by even extremely minute quantities of the alkaloid. 
 Applied in the form of ointment to the eye, it causes much the 
 same effects, with, according to Dr. Pereira, contraction of the 
 pupil. Aconitine is unchanged by exposure to the air. When 
 moderately heated in a tube, it fuses to a transparent liquid, 
 which, as the heat is increased, becomes brown, then black, and 
 is finally reduced to a solid carbonaceous mass. Heated in the 
 air on a piece of porcelain, it undergoes a similar change, and 
 leaves a black cinder, which is but slowly consumed : it can not 
 be volatilised unchanged. 
 
 Aconitine, other than that prepared by Mr. Morson, of Lon- 
 don, as found in the shops, is usually more or less colored, and 
 very variable in strength, many of the samples being almost 
 wholly inert. Dr. Pereira states that he met with a French 
 preparation of which he took one grain without perceiving the 
 least effect either on the tongue or otherwise. And of three 
 samples prepared by different German manufacturers that we 
 have examined, one of them contained only a mere trace of 
 the alkaloid, and the other two appeared to consist entirely 
 of foreign matter. The aconitine prepared by Mr. Morson, is 
 usually in the form of a dull-white powder, consisting chiefly of 
 small granules and thin transparent plates. This manufacturer, 
 as well as Mr. Grroves, has recently obtained the alkaloid in the 
 form of large well-defined crystals. 
 
 Aconitine has strongly basic properties, completely neutral- 
 ising acids to form salts, several of which have been obtained 
 in the crystalline form. When touched in the dry state with 
 concentrated sulphuric acid, pure aconitine acquires a faint yel- 
 low color, and dissolves to a colorless solution; a small crystal 
 of nitrate of potash stirred in the solution, produces no visible 
 change, even on the application of a moderate heat ; if a crys- 
 tal of bichromate of potash be stirred in the solution, the mix- 
 ture slowly acquires a green color. Concentrated nitric acid 
 also dissolves the alkaloid to a colorless solution, which is un- 
 changed by a moderate heat, and by a solution of protochloride 
 of tin. The alkaloid is also dissolved to a colorless solution, by 
 hydrochloric acid. 
 
616 ACONITINE. 
 
 Solubility. — When excess of Morson's aconitine is kept in 
 contact with pure water at a temperature of about 60° F. for 
 ten hours, one part dissolves in 1,783 parts of the fluid. On 
 evaporating the solution tp dryness, the alkaloid is left in the 
 form of a hard, transparent, colorless pellicle, which when 
 broken up, presents the appearance of crystalline plates. Abso- 
 lute ether kept in contact with excess of the alkaloid for several 
 hours, at the ordinary temperature, takes up one part in 777 
 parts of the menstruum. On allowing the solution to evaporate 
 spontaneously, the alkaloid is left as a transparent glacial mass. 
 Chloroform readily dissolves it in nearly every proportion, and 
 leaves it on spontaneous evaporation in the form of a vitreous 
 mass. It is also freely soluble in alcohol. The salts of aconi- 
 tine are, with few exceptions, readily soluble in water. Thej' 
 are also soluble in alcohol, but insoluble in ether. 
 
 Of solutions of Aconitine. — In the following investiga- 
 tions in regard to the behavior of solutions of aconitine, pure 
 aqueous solutions of the chloride were employed. The frac- 
 tions indicate the fractional part of a grain of the pure alka- 
 loid present in one grain of liquid ; and, unless otherwise stated, 
 the results refer to the behavior of one grain of the solution. 
 
 1. Potash and Ammonia. 
 
 The caustic alkalies throw down from somewhat concentrated 
 solutions of salts of aconitine a dirty-white flocculent precipitate 
 of the hydrate of the alkaloid, which is nearly wholly insoluble 
 in excess of the precipitant, but readily soluble in free acids, 
 even acetic acid. 
 1. xoo" grain of aconitine, in one grain of water, yields a rather 
 
 copious precipitate, which is insoluble in large excess of 
 
 the reagent. 
 '^- 5^0^ grain, yields a quite good precipitate, which dissolves, 
 
 not however without difficulty, in several drops of the 
 
 precipitant. 
 3. r,wo grain : no satisfactory indication. 
 
 The alkaline carbonates fail to produce a precipitate with 
 a 100th solution of the alkaloid. 
 
CARBAZOTIC ACID AND IODINE TESTS. 617 
 
 2. Chloride of Gold. 
 
 Terchloride of gold produces in solutions of salts of aconitine, 
 even when highly diluted, a yellow amorphous precipitate of the 
 double chloride of aconitine and gold, which is but very spar- 
 ingly soluble in hydrochloric acid. According to Planta, the 
 precipitate has the composition, CeoH^^NOu, HCl, AuClg, 2 HO. 
 
 1- ToT grain of aconitine, yields a very copious precipitate. 
 
 2- 1 , J grain, yields a quite good deposit, which is readily sol- 
 
 uble to a clear solution in caustic potash. 
 
 3- 57oo"o grain : in a very little time, a quite fair precipitate. 
 
 4. ]- o,ooo grain, yields, after a little time, a quite perceptible 
 
 deposit. 
 5- T o.ooo grain : after some time, a just perceptible turbidity. 
 
 3. Carbazotic Acid. 
 
 An alcoholic solution of carbazotic acid occasions in solutions 
 of salts of aconitine a yellow amorphous precipitate, which is 
 insoluble in ammonia. 
 
 !• Too" grain of aconitine, in one grain of water, yields a very 
 copious precipitate. 
 
 2. TT^oo grain, yields a quite fair, greenish-yeUow deposit. 
 
 3. 5,Joo grain: after a little time, a quite perceptible precipitate. 
 
 4. Iodine in Iodide of Potassium. 
 
 An aqueous solution of iodine in iodide of potassium throws 
 down from solutions of aconitine and of its salts, even when 
 highly diluted, a reddish-brown or yellowish, amorphous precip- 
 itate, which is readily decomposed by the caustic alkalies. 
 
 1. Yoo" grain of aconitine, yields a very copious precipitate, 
 
 which on the addition of caustic potash is changed to a 
 white deposit. 
 
 2. 1000 grain : a copious, yellowish precipitate, which is soluble 
 
 in the caustic alkalies, but immediately replaced by a 
 white deposit. 
 
618 ACONITINE. 
 
 3. roTo"5"o grain : a quite good precipitate. 
 
 4. 5-0.000 grain, yields a quite distinct deposit. 
 
 5- ro"o!o"oo grain: the mixture becomes distinctly turbid. 
 
 5. Bromine in Bromohydric Acid. 
 
 A strong aqueous solution of bromohydric acid saturated 
 with bromine produces in solutions of salts of aconitine, and of 
 the free alkaloid, a yeUow flocculent precipitate. 
 1. YoF grain of aconitine, in one grain of water, yields a copi- 
 ous precipitate. 
 2- T7s-o"o grain : a quite good deposit. 
 
 3. ro.o Qo grain: a quite fair precipitate. 
 
 4. 2 5 ,0 o 'o grain, yields a distinct cloudiness. 
 
 Other Reagents. — Corrosive siiblimate produces in one grain 
 of a 100th solution of salts of aconitine a quite good, dirty- 
 white, caseous precipitate, which is readily soluble in hydro- 
 chloric acid. A similar quantity of a 500th solution of the alka- 
 loid fails to yield a precipitate. SulpJiocyanide of potassium and 
 tannic acid produce a perceptible cloudiness in a 100th solution 
 of salts of the alkaloid. With stronger solutions, these reagents 
 produce distinct precipitates. 
 
 Bichloride of platinum, the chromates of potash, iodide of 
 potassium, and ferro- and ferri-cyanide .of potassium fail to 
 produce a precipitate with a, 100th solution of the chloride of 
 the alkaloid. 
 
 Fallacies. — None of the reactions now described are in them- 
 selves characteristic of aconitine, they being common to many 
 of the alkaloids and certain other organic principles ; nor is 
 there at present any chemical reaction known that in itself is 
 peculiar to this substance. By, however, the concurrent reac- 
 tion of several of these reagents, taken in connection with the 
 peculiar effects of the alkaloid upon the tongue, its nature may 
 be fully established, even when present only in very minute 
 quantity. In fact, the symptoms produced by this substance 
 are usually so peculiar that they alone, when fuUy known, may 
 enable the medical jurist to determine the cause of death, even 
 
SEPARATION FROM ORGANIC MIXTURES. 619 
 
 when the chemical evidence has entirely failed. A case of this 
 kind, in which the root of aconite had been criminally admin- 
 istered and no trace of the poison was discovered in the body, 
 is related by D^. Geoghegan. (Dublin Medical Journal, July, 
 1841, p. 403.) 
 
 Physiological Test. — Much the most characteristic test yet 
 known for the recognition of aconitine, is its peculiar physiolog- 
 ical action when applied to the tongue or in the form of solution 
 to the skin. A drop of water holding in solution, in the form 
 of a salt, only the 1,000th part of a grain of the alkaloid, when 
 placed upon the end of the tongue, causes, as first observed by 
 Dr. Headland, a very decided tingling and numbness of that 
 organ, which continue for nearly an hour. According to Dr. 
 Headland (Action of Medicines, p. 448), the 100th of a grain 
 dissolved in alcohol and rubbed into the skin, produces loss of 
 feeling, lasting for some time ; and the 50th of a grain will kill 
 a small bird almost instantly. 
 
 Sepaeation feom Organic Mixtures. 
 
 Suspected Solutions and Contents of the Stomach. — In sus- 
 pected poisoning by aconite in its crude state, before proceeding 
 to a chemical examination of the mixture presented for examin- 
 ation, the analyst should carefully examine it for any solid por- 
 tions of the plant, which, if found, may be identified by their 
 botanical characters. All parts of the plant have a bitter taste, 
 which is soon followed by a persistent sense of numbness and 
 tingling in the lips and. tongue. 
 
 Aconitine may be separated from the contents of the stom- 
 ach, and like mixtures, in the same manner as heretofore de- 
 scribed for the recovery of nicotine {ante, p. 438), or by the 
 method of Stas. The alkaloid is more readily extracted from 
 aqueous mixtures by chloroform than by ether, it being much 
 more soluble in the former than in the latter liquid. The resi- 
 due obtfiined on evaporating the chloroform or ether extract, 
 should at first be stirred with a few drops of water containing 
 a trace of acetic acid, and a small portion of the mixture ap- 
 plied to the end of the tongue. If this experiment indicates 
 
620 ACONITINE. 
 
 the presence of a very notable quantity of the poison, the 
 remaining portion of the mixture may be dissolved in an appro- 
 priate quantity of acidulated water and the solution examined 
 by some of the chemical tests. Should, however, the portion 
 applied to the tongue fail to indicate the presence of the alka- 
 loid, another and larger portion should be examined in the same 
 manner, even if the whole of the mixture be thus consumed, 
 since without the corroboration of this physiological test, the 
 chemical tests, at present known, would be of no avail. 
 
 On applying the method heretofore pointed out for the de- 
 tection of nicotine, to the examination of the contents of the 
 stomach of a dog, killed in fourteen minutes by a drachm of 
 ordinary tincture of the root of aconite, the presence of acon- 
 itine was very fully established. 
 
 From the Blood. — Absorbed aconitine may be recovered from 
 the blood, by slightly acidulating the fluid with sulphuric acid 
 and agitating it in a wide-mouthed bottle with something more 
 than its own volume of diluted alcohol, until the mixture be- 
 comes homogeneous. It is then placed in an evaporating dish 
 and exposed for some time, with frequent stirring, to a moder- 
 ate heat ; the cooled mass is transferred to a moistened linen 
 strainer, and the solids retained by the strainer well washed 
 with diluted alcohol and strongly f)ressed. The liquid is now 
 concentrated at a moderate heat, again strained, then evapo- 
 rated to a small bulk, filtered through paper, and evaporated 
 on a water-bath to about dryness. The residue thus obtained 
 is well stirred with about half a drachm of pure water, the so- 
 lution filtered, then rendered alkaline by caustic potash, and 
 thoroughly agitated with about two volumes of chloroform, 
 which, after separation and decantation, is allowed to evaporate 
 spontaneously, when the alkaloid will usually be left sufficiently 
 pure for testing. 
 
 About forty minims of the tincture of aconite root were ad- 
 ministered to a small dog. The animal immediately indicated 
 an uneasy sensation in the mouth and throat, and soon vomited 
 a white frothy mucus, then lost the use of his legs, made re- 
 peated attempts to vomit, had spasmodic convulsions with slow 
 breathing, and died in sixty-four minutes after the dose had 
 
ATROPINE. 621 
 
 been given. Twelve fluid drachms of blood, taken immediately 
 from the animal, were submitted to the foregoing method of 
 analysis, and the chloroform residue stirred with two drops of 
 water containing the merest trace of acetic acid. A drop of this 
 mixture placed upon the tongue, gave, in a little time, perfectly 
 unequivocal evidence of the presence of aconitine. The remain- 
 ing drop of the mixture was diluted with two drops of pure 
 water, and examined in three separate portions by carbazotic 
 acid, chloride of gold, and a solution of bromine, all of which 
 produced precipitates very similar in quantity with those pro- 
 duced from a 1,500th solution of the alkaloid. The entire quan- 
 tity of the poison recovered, could hardly have exceeded the 
 300th part of a grain, and may have been even much less than 
 this, since it is by no means certain that the precipitates pro- 
 duced by the reagents were perfectly pure : in fact, the con- 
 trary is much the more probable. 
 
 Twenty-five minims of the same tincture of aconite were 
 given to a healthy cat. The animal was soon seized with 
 violent vomiting, lost the power of walking, frothed at the 
 mouth and nose, and died under violent symptoms within thirty 
 minutes. The chloroform residue obtained from one ounce of 
 blood from this animal, when stirred with a few drops of acid- 
 ulated water and examined by chloride of gold and a solution 
 of bromine, gave reactions similar to those produced from a 
 quite dilute solution of aconitine; yet, about one-half of the 
 residue, when applied to the tongue, failed to produce any 
 decided efi'ect upon that organ. It can not, of course, under 
 these circumstances be claimed that the gold and bromine reac- 
 tions were really due to the presence of aconitine. 
 
 Section IL — Atropine. (Belladonna.) 
 
 History. — Atropine is the active principle, or alkaloid, of 
 Atropa Belladonna, or Deadly Nightshade. It exists in the root, 
 leaves, and berries of the plant. The existence of this prin- 
 ciple was first announced, in 1819, by Brandos; but it was first 
 obtained in its pure state by Mein, a German pharmaceutist, 
 
622 ATROPINE. 
 
 in 1833. Its composition, according to the analyses of Planta, 
 is C34H23NO6. It is a white crystallisable solid, and a most 
 virulent poison. 
 
 Preparation. — Atropine may be obtained, according to M. 
 Rabourdin (Comptus Rendus, Oct. 14, 1850), in the following 
 manner. The fresh leaves of the plant are well bruised and 
 submitted to pressure to extract the juice; this is then heated 
 to about 185° F. in order to coagulate the albumen, and filtered, 
 after which it is rendered alkahne by caustic potash and thor- 
 oughly agitated for a few minutes with chloroform. In about 
 half an hour, the latter fluid, holding in solution the atropine 
 and having the appearance of a greenish oil, wiU have subsided 
 to the bottom of the mixture. The supernatant liquid is then 
 decanted, and the chloroform solution washed with successive 
 portions of water, as long as this liquid becomes colored. The 
 chloroform solution is then transferred to a tubulated retort, 
 and distilled in a water-bath, until all the chloroform has passed 
 into the receiver, when the residue is treated with a little water 
 acidulated with sulphuric acid, which will dissolve the atropine, 
 leaving a green resiaous matter. The solution thus obtained is 
 filtered, the filtrate treated with slight excess of carbonate of 
 potash, and the precipitated atropine collected on a filter, 
 washed, and dissolved in rectified alcohol, which upon spon- 
 taneous evaporation will leave the alkaloid in beautiful groups 
 of acicular crystals. 
 
 In the absence of the fresh plant, M. Rabourdin recom- 
 mends to employ the extract of belladonna. Thirty parts of 
 the extract are dissolved in one hundred parts of water, and 
 the filtered solution agitated, for about a minute, with two parts 
 of caustic potash and fifteen parts of chloroform. The subse- 
 quent steps of the process are the same as directed above, 
 except that the washed chloroform solution, instead of being 
 distilled, is allowed to evaporate spontaneously. The product 
 obtained by either of these methods, if not perfectly colorless, 
 may be further purified, as first advised by Professor Procter, 
 of Philadelphia, by redissolving it in water acidulated with 
 sulphuric acid, and extracting the foreign organic matter by 
 chloroform; the aqueous solution is then rendered alkaline 
 
PHYSIOLOGICAL EFFECTS. 623 
 
 by potash, and the liberated alkaloid extracted with fresh 
 chloroform, which on spontaneous evaporation will leave it in 
 its pure state. 
 
 Mein, in his experiments, obtained twenty grains of atropine 
 from twelve ounces of the fresh root of belladonna ; and Luxton, 
 between five and six grains from one thousand grains of the 
 fresh leaves. (U. S. Dispensatory, 1865, p. 1018.) On an 
 average, perhaps, the green root and leaves do not contain 
 over about one-third of one per cent, of the alkaloid. The 
 ordinary medicinal dose of atropine, and its salts, is about one- 
 thirtieth of a grain. The pharmaceutical extracts and tincture 
 of belladonna, are each subject to great variation in strength. 
 The dose of the former, for an adult, is at first from one-fourth 
 to one-half a grain ; that of the latter, from fifteen to twenty- 
 five minims. 
 
 Poisoning by atropine in its pure state, has been of rather 
 rare occurrence; but numerous instances of poisoning by the 
 berries and some of the preparations of belladonna, are recorded. 
 With few exceptions, however, all these cases have been the 
 result of accident, most of them having been occasioned by 
 the berries being eaten through ignorance of their properties. 
 The berries have considerable resemblance to cherries, and a 
 sweet, but mawkish taste. 
 
 Symptoms. — The most constant symptoms occasioned by 
 poisonous doses of belladonna are, dryness of the mouth and 
 throat, difiiculty of deglutition, dilatation of the pupils, impaired 
 vision, and delirium, succeeded by drowsiness and stupor. The 
 delirium is generally of a pleasing character, but sometimes of 
 a furious nature. These efi^cts are usually attended with a 
 sense of burning* and constriction of the throat, impaired articu- 
 lation, great thirst, giddiness, numbness of the limbs, a stagger- 
 ing gait, nausea and sometimes vomiting, spectral illusions, 
 and great mental excitement. The pulse becomes quick and 
 small, and sometimes the face red and turgid, and the eyes 
 wholly insensible to light. The secretions are usually increased; 
 and irritation of the urinary organs has sometimes occurred; 
 and in some instances, a scarlet eruption has appeared on the 
 skin. In fatal cases, death is usually preceded by coldness of 
 
624 ATROPINE. 
 
 the extremities, a rapid and intermittent pulse, deep coma, and 
 sometimes, though rarely, convulsions. 
 
 The following symptoms were observed in one hundred and 
 fifty French soldiers, who had eaten the berries of the plant: 
 Dilatation and immobility of the pupil, with total insensibility 
 of the eye to the presence of external objects, or at least con- 
 confused vision; bluish injectiqn of the conjunctiva; great prom- 
 inence of the eye; dryness of the lips, tongue, and throat; 
 difficult,-, and in some cases impossible deglutition; nausea, but 
 no vomiting; great weakness, with difficulty or impossibility of 
 standing; continual movement of the hands and fingers; lively 
 delirium, accompanied with a siUy laugh ; aphonia, or confused 
 sounds uttered with difficulty ; and ineifectual attempts to empty 
 the bowels. These effects were followed by very gradual return 
 to health and reason, without any recollection of the preceding 
 state. (Orfila's Toxicologie, 1852, ii, 478.) 
 
 The symptoms produced by belladonna, as usually developed, 
 could not readily be confounded with those of any other sub- 
 stance, except stramonium and hyoscyamus (Pereira). The 
 symptoms usually manifest themselves within an hour after the 
 poison has been taken; but they have frequently been delayed 
 for several hours, especially in poisoning by the berries. Of 
 the numerous recorded cases of poisoning by this substance, 
 but comparatively few proved fatal, and in these the time of 
 death varied from a few hours to some days. The eifects in 
 non-fatal cases are frequently very slow in disappearing, some- 
 times lasting for several days or even weeks. 
 
 A healthy man ate of a pie made with the berries of bella- 
 donna and apples. A few minutes after taking his dinner, he 
 complained of feeling drowsy; the lethargy soon increased, his 
 countenance changed color, the pupils became dilated, and he 
 experienced a strange coppery taste in his mouth. On going 
 up stairs, he staggered, and upon entering his room, fell, and 
 became insensible. He subsequently became delirious and con- 
 vulsed, and died the following morning. A child to whom a 
 portion of the pie had been given, died on the same day. 
 (New York Jour, of Med., vol. viii, p. 284.) In four recent 
 cases in which some boys had eaten a quantity of the extract 
 
PHYSIOLOGICAL EFFECTS. 625 
 
 of belladonna, in one instance as much as a drachm, the follow- 
 ing symptoms were observed in one of the cases. When first 
 seen by a physician the patient was quite delirious, the delirium 
 being of a fantastic character; he could neither hear nor speak 
 plainly, and labored under hallucinations, but was otherwise 
 unconscious. The pupils were widely dilated, and the eyes had 
 a staring look. At first he complained of some pain in the 
 throat and of his imperfect sight, objects appearing white to 
 him. The pulse was very feeble, and almost countless; and 
 there was great difficulty of swallowing. Under active treat- 
 ment, including the use of an emetic, the delirium having lasted 
 eighteen hours gradually passed away; but it was not until the 
 lapse of forty hours that he was perfectly rational. Much the 
 same symptoms were present in the three other cases. All the 
 patients finally recovered. (Lancet, 1860, vol. i, p. 133.) 
 
 The following instance of recovery is related by Dr. H. M. 
 Gray (New York Jour, of Med., Sept., 1845, p. 182). A child, 
 between two and three years of age, swallowed from eight to 
 twelve grains of the extract of belladonna. Something over 
 half an hour after taking the poison, the expression of the 
 patient was that of terror; the pupils were widely dilated and 
 immovable, the conjunctiva highly injected, and the whole eye 
 prominent and very brilliant. The face, upper extremities, and 
 trunk of the body exhibited a diff^use scarlet efflorescence studded 
 with innumerable papillae, very closely resembling the rash of 
 scarlatina. The skin was hot and dry ; the pulse much increased 
 in force and frequency; the respiration anxious, and attended 
 with the stridulous sound of croup. There was also a constant 
 but unsuccessful effort at deglutition, with spasmodic action of 
 the muscles of the throat and pharynx; and paroxysms of 
 violent motion and rapid automatic movements, attended with 
 convulsive laughter. Under the action of an emetic, the alarm- 
 ing symptoms passed off in about three hours, and the child 
 soon recovered, with the exception of a moderate diarrhoea and 
 a slight enlargement of the pupil. 
 
 The external application of belladonna, and its administration 
 in the form of an enema, has in several instances given rise to 
 serious and even fatal results. A case is related in which an 
 
 40 
 
626 ATROPINE. 
 
 injection of a decoction of the root caused the death of an adult 
 in five hours; and another, in which only two grains of the 
 extract, administered in the same manner, gave rise to alarming 
 symptoms. Dr. Lyman relates an instance in which the appli- 
 cation of a small belladonna plaster, to the chest of a nervous 
 woman, produced all the usual symptoms of poisoning by that 
 substance, from which the patient did not entirely recover until 
 after four or five days. Two very recent cases of this kind, 
 in which a lotion of belladonna had been applied, are mentioned 
 in the ''Chemical News" (London, Nov., 1866, p. 216). 
 
 Atropine. — The symptoms produced by atropine in its pure 
 state, are the same in kind as those occasioned by belladonna, 
 but they are usually much more prompt in appearing. In a 
 case related by Dr. Schmid, a stout healthy man swallowed 
 from one-sixth to one-fourth of a grain of the alkaloid in solu- 
 tion. An hour afterwards, the patient was in a state of fearful 
 excitement; the tongue was swollen and projected between the 
 teeth, and he incessantly moved it and his lips in a stammering 
 manner, but without emitting a single intelligible word. The 
 eyes were staring; the head hot, and the countenance livid; 
 the pupils dilated to their utmost, and insensible to light; the 
 pulse was rapid, full, and strong, and there was a constant 
 desire, but without the power, to make water. During the 
 following hoar the excitement continually increased, when the 
 subcutaneous injection of a fifth of a grain of acetate of morphia 
 into the right temple was soon succeeded by a state of calm. 
 After two hours more, the excitement had again attained almost 
 its former hight, but it was again subdued by a repetition of 
 the morphine injection. The patient now gradually recovered, 
 the only symptoms remaining about twenty-four hours after the 
 occurrence being extreme weakness, dryness of the throat, 
 slight twitchings of the limbs, and a dilated state of the pupils. 
 (Amer. Jour. Med. Sci., July, 1866, p. 269.) 
 
 In a case recorded by Dr. Taylor, two grains of the alkaloid 
 caused the death of a young man. The young man took the 
 dose on going to bed, and he was found dead the next morning : 
 no trace of the poison was detected in the stomach or its con- 
 tents. (On Poisons, p. 830.) Dr. Andrew, of Edinburgh, 
 
EXTERNAL APPLICATION. 627 
 
 relates an instance in which two-thirds of a grain, taken in 
 mistake by a female, produced most violent symptoms from 
 which the patient did not entirely recover for more than a week. 
 (Wharton and Still^'s Med. Jur., p. 639.) The internal admin- 
 istration of even only one-tenth of a grain has been followed 
 by alarming symptoms. On the other hand, Dr. Roux has re- 
 cently reported an instance in which a lady, in a fit of despair, 
 swallowed a solution containing nearly two grains of atropine, 
 and entirely recovered, not however without sufifering the most 
 severe symptoms. The treatment employed in this case, con- 
 sisted of emetics, followed by a strong decoction of cofi'ee, and 
 M. Bouchardat's solution of iodine in iodide of potassium. 
 
 The employment of atropine in the form of subcutaneous in- 
 jection has in several instances been followed by very serious 
 symptoms, even when injected in very ininute quantity. Thus, 
 Dr. Eulenberg relates an instance in which he employed in this 
 manner, in the case of a lady affected with facial neuralgia, 
 l-48th of a grain of the alkaloid, and alarming symptoms of 
 poisoning soon appeared. The patient threw herself about the 
 bed entirely unconscious, and from time to time broke out in 
 furious delirium ; the limbs, and also the head, were shaken 
 with convulsive jerkings. The pupils were moderately dilated, 
 the pulse small, and somewhat increased in frequency. An im- 
 mediate injection of one-third of a grain of morphine into the 
 temporal region, in close proximity to the former place of injec- 
 tion, was followed within about three minutes by a cessation of 
 the twitchings, and in ten minutes the patient fell into a heavy 
 peaceful sleep, from which she awoke in eight hours without 
 any symptom of the poison being present. (Amer. Jour. Med. 
 Sci., April, 1866, p. 434.) In another case, related by Dr. 
 Lorent, less than the 1-lOOth of a grain of the alkaloid, em- 
 ployed in this manner, produced very alarming results. 
 
 The external application of atropine may speedily produce 
 death. In an instance reported by Dr. Ploss, of Leipsic, an 
 ointment composed of fifteen parts of sulphate of atropia to 
 seven hundred parts of lard, applied as a dressing to a blistered 
 surface on the neck of a man, caused death, under the most 
 violent symptoms of belladonna poisoning, within two hours 
 
628 ATROPINE. 
 
 after the application had been made. (Ibid., April, 1865, p. 
 541.) A few drops of an aqueous solution containing two-thirds 
 of a grain of the alkaloid to the ounce of fluid,' applied to the 
 eye of a man affected with cataract, produced violent constitu- 
 tional effects, with constant hallucinations, and inabilitj to pass 
 urine ; the violent delirium continued during the ensuing night, 
 and it was some days before the patient entirely recovered. 
 
 Treatment. — This consists, in case the poison has been 
 swallowed, in the speedy administration of an emetic or the 
 employment of the stomach-pump. Of the various chemical 
 antidotes that have been proposed, may be mentioned tannic 
 acid, a solution of iodine in iodide of potassium, hydrate of 
 magnesia, and animal charcoal. If either of these substances 
 be employed, it should only be in connection with emetics or 
 the use of the stomach-pump. As a physiological antidote, 
 morphine administered either by the mouth or by subcutaneous 
 injection, has been strongly advised ; and instances are reported, 
 as in some of those already mentioned, in which this treatment 
 was followed by rapid recovery. (See Treatment of poisoning 
 by opium, ante, p. 464.) 
 
 Post-mortem Appearances. — These, as in death from most 
 of the vegetable poisons, are subject to considerable variation. 
 The more constant appearances are, a dilated state of the pu- 
 pils, more or less redness of the mucous membrane of the stom- 
 ach and small intestines, fullness of the cerebral vessels, and 
 congestion of the lungs. The blood is usually dark colored and 
 liquid. Instances are related, however, in which this poison 
 produced death without leaving any notable morbid change in 
 the body. 
 
 Chemical Properties. 
 
 In the Solid State. — Atropine, in its pure state, is a white, 
 odorless solid, which crystallises in the form of transparent 
 prisms, usually aggregated into beautiful tufts or stellated 
 groups. It has a bitter, acrid taste. When heated in a tube, 
 it readily fuses to a colorless, transparent liquid, which ascends 
 the sides of the tube; upon cooling, the liquid becomes a clear 
 gummy mass, and ultimately concretes to a vitreous solid. When 
 
CHEMICAL PROPERTIES. 629 
 
 gradually heated on porcelain, it fuses and is slowly dissipated, 
 giving rise to dense white, fumes. According to Planta, the fus- 
 ing point of atropine is 194° F., and at 284°, it is volatilised, 
 partially unchanged, the greater part undergoing decomposition. 
 (Chem. Gazette, .1850, p. 349.) When rapidly heated, it melts, 
 puffs up, then evolves dense white fumes, and takes fire, burning 
 with a bright flame, and leaving a shining black cinder, which 
 may be entirely consumed. Heated in contact with a fixed 
 caustic alkali, it readily undergoes decomposition with the evo- 
 lution of ammonia. 
 
 Atropine has strongly basic properties, and completely neu- 
 tralises even the most powerful acids forming salts, several of 
 which are readily crystaUisable. Concentrated nitric acid dis- 
 solves the pure alkaloid without change of color, even upon the 
 application of heat : the subsequent addition of chloride of tin 
 produces no visible change. So, also, concentrated sulphuric 
 acid dissolves it to a colorless solution, which is unchanged by 
 a crystal of nitrate of potash ; on the addition of a crystal of 
 bichromate of potash, the acid solution slowly acquires a green 
 color, due to the formation of sesquioxide of chromium. 
 
 Solubility. — A sample of atropine examined by Planta, was 
 soluble in 299 parts of water at the ordinary temperature ; but 
 a single experiment in our own hands, indicated that the alka- 
 loid requires 414 parts of that liquid for solution, even after 
 several hours digestion. It is readily soluble in nearly every 
 proportion in alcohol and in chloroform, and freely soluble in 
 absolute ether. Upon spontaneous evaporation, it separates 
 from either of these liquids, in the crystalline form. A satu- 
 rated aqueous solution of the alkaloid, has a well-marked alka- 
 line reaction. Most of the salts of atropine are freely soluble 
 in water and in alcohol ; but they are almost wholly insoluble 
 in ether and chloroform, at least this is the case with the sul- 
 phate and chloride. 
 
 Of Solutions of Atropine. — The following results, in re- 
 gard to the behavior of solutions of atropine, are based upon 
 the examination of two apparently perfectly pure specimens of 
 the alkaloid, prepared by different well-known European man- 
 ufacturers, one of the samples being employed in the form of 
 
630 ATROPINE. 
 
 sulphate, and the other as chloride. The fractions employed 
 indicate the fractional part of a grain of the pure alkaloid 
 present in one grain of water ; and the results, unless otherwise 
 indicated, refer to the behavior of one grain of the solution. 
 
 1. The Alkalies and Alkaline Carbonates. 
 
 Caustic potash and soda throw down from concentrated 
 aqueous solutions of salts of atropine a white, amorphous pre- 
 cipitate of the pure alkaloid, which is readily soluble in free 
 acids, and also in large excess of the precipitant. After a 
 time, especially if the mixture has been stirred, the precipitate 
 assumes the crystalline form. The presence of foreign organic 
 matter readily prevents the formation of crystals. 
 
 One grain of a 100th solution of the alkaloid yields a quite 
 copious precipitate, which on being stirred with a glass rod, in 
 a little time, becomes a mass of crystals, of the forms illustrated 
 in Plate XII, fig. 4. Solutions but little more dilute than this, 
 fail to yield a precipitate. 
 
 Ammonia produces in solutions of salts of the alkaloid the 
 same precipitate as occasioned by the fixed caustic alkalies; 
 but the deposit is much more readily soluble in excess of the 
 precipitant. 
 
 Carbonate of potash produces in a 100th solution of the 
 alkaloid a distinct turbidity; but the carbonates of soda and 
 ammonia fail to produce, in a similar solution, any visible 
 reaction. 
 
 2. Bromine in Bromoliydric Acid. 
 
 An aqueous solution of bromohydric acid saturated with 
 free bromine produces in solutions of salts of atropine and of 
 the free alkaloid, even when highly diluted, a yellow amorphous 
 precipitate, which in a little time becomes crystalline. The 
 precipitate from somewhat strong solutions of the alkaloid, after 
 a time disappears; but it is immediately reproduced upon 
 further addition of the reagent. The precipitate is insoluble 
 in acetic acid, and only very sparingly soluble in large excess 
 of hydrochloric, nitric, and sulphuric acids, and in the fixed 
 
CARBAZOTIC ACID TEST. 631 
 
 caustic alkalies : it is even produced from solutions of the alka- 
 loid in concentrated sulphuric acid. 
 
 !• T^o' grain of atropine, in one grain of water, yields a very 
 copious, bright-yellow, amorphous precipitate, which very 
 soon, beginning along the margin, becomes a mass of 
 crystals, Plate XII, fig. 5. After several minutes, most 
 of the crystals dissolve, but they may be reproduced, 
 even several times, by further addition of the reagent. 
 
 2. rr^oo grain, yields a copious, yellow deposit, which soon 
 
 furnishes crystals, having the forms illustrated above. 
 
 3. 10,0 grain: a quite good, yellowish precipitate, which in 
 
 a few moments becomes granular and crystalline, and 
 presents the appearance figured in Plate XII, fig. 6. 
 
 4. 2 5,000 grain: in a very little time, a quite satisfactory 
 
 deposit of short crystalline needles, and granules. 
 5- 5 0,000 grain: after some minutes, some few granules appear, 
 
 but the result is not satisfactory. 
 The production of the above crystals is quite characteristic 
 of this alkaloid. Although the reagent produces yeUow precip- 
 itates with most, if not all, the other alkaloids, and with certain 
 other organic substances; yet all these deposits, with the excep- 
 tion of that from opianyl, unlike the atropine precipitate, remain 
 amorphous. The crystallised atropine deposit is readily distin- 
 guished from the opianyl compound, by its form. It may here 
 be remarked that the reagent produces a similar crystalline 
 precipitate with daturine, but, as will be pointed out hereafter, 
 this alkaloid is identical with atropine. We have found the 
 precipitate become crystalline in the presence of even compara- 
 tively large quantities of foreign organic matter. In the absence 
 of a solution of bromohydric acid, an alcoholic solution of 
 bromine may be employed as the reagent. 
 
 3. Carhazotic Acid. 
 
 An alcoholic solution of carbazotic acid occasions in some- 
 what strong solutions of salts of atropine a yellow, amorphous 
 precipitate, which is readily soluble in acids, even in acetic acid. 
 After a time, the precipitate becomes more or less crystalline. 
 
632 ATROPINE. 
 
 !• ToTT grain of atropine, yields a copious, light yellow deposit. 
 If the mixture be stirred with a glass rod, it soon yields 
 streaks of granules along the path of the rod, and in a 
 little time the deposit becomes entirely crystalline, the 
 crystals being principally in the form of transparent plates, 
 and these more or less aggregated into very beautiful 
 groups, Plate XIII, fig. 1. 
 
 2. r,"^o"o grain: within a few moments, a slight, greenish-yellow 
 
 precipitate appears, and in a little time, there is a quite 
 good deposit. If the mixture be stirred, it soon yields a 
 fine crystalline deposit. 
 •^- sTFTo grain: upon stirring the mixture, it yields, after a little 
 time, caseous streaks over the bottom of the watch-glass 
 containing the mixture; but the ^reaction is not very 
 satisfactory. 
 This reagent also produces crystalline precipitates with vari- 
 ous other substances, but the forms illustrated above are quite 
 peculiar to atropine. 
 
 4. Terehloride of Gold. 
 
 This reagent produces in solutions of salts of atropine, when 
 not too dilute, a light yellow, amorphous precipitate of the 
 double chloride of atropine and gold, which after a time be- 
 comes converted into crystals. The precipitate is insoluble in 
 potash, and but sparingly soluble in acetic and hydrochloric 
 acids. 
 1 . Yo^ grain of atropine, yields a copious precipitate, which 
 
 soon becomes a mass of crystals, having the peculiar forms 
 
 shown in Plate XIII, fig. 2. 
 ^- T^'o'o grain, yields a good deposit, which soon, especially if 
 
 the mixturp be stirred, assumes the crystalline form. 
 
 3. sToo^ grain, yields no indication, even after the mixture has 
 
 stood some time. 
 The crystalline form of the double atropine salt, as figured 
 above, readily distinguishes it from other substances. The 
 formation of these crystals, however, is readily prevented by 
 the presence of foreign organic matter. 
 
PHYSIOLOGICAL TEST. 633 
 
 5. Iodine in Iodide of Potassium. 
 
 A solution of iodine in iodide of potassium throws down 
 from solutions of salts of atropine, and of the free alkaloid, a 
 reddish-brown, amorphous precipitate, which is insoluble in 
 acetic acid, and only sparingly soluble in potash. 
 !• ToT grain of atropine, yields a very copious precipitate, 
 
 which dissolves, to a clear solution, in about three drops 
 
 of a saturated solution of caustic potash. 
 2- 1,000 grain: a quite copious precipitate. 
 
 3. 10,0 grain, yields a very good deposit. 
 
 4. 5 0.0 grain, yields at first a yellowish turbidity, and after 
 
 a little time, a distinct, reddish-brown precipitate. 
 5- 10 0% grain, yields a very distinct turbidity. 
 
 The reaction of this reagent is common to a large class of 
 substances. 
 
 Other Reagents. — Tannic acid produces in solutions of salts 
 of atropine, a dirty-white, amorphous precipitate, which is 
 readily soluble in the caustic alkalies and in free acids. One 
 grain of a 100th solution of the alkaloid yields a copious 
 deposit; and a similar quantity of a 1,000th solution, a quite 
 distinct reaction. Bichloride of platinum, and chloride of palla- 
 dium, throw down from concentrated solutions of salts of the 
 alkaloid, dirty-brown, amorphous precipitates. Strong solutions 
 of salts of atropine, when treated with a stream of chlorine gas, 
 become slightly turbid, and yield on the subsequent addition of 
 ammonia, a white precipitate. 
 
 Iodide of potassium, sulphocyanide of potassium, the chro- 
 mates of potash, chloride of mercury, nitrate of mercury, ferro- 
 and ferri-cyanide of potassium, and gallic acid .fail to precipitate 
 even concentrated solutions of salts of atropine. 
 
 Physiological Test. — The property possessed by atropine of 
 dilating the pupil of the eye, has been proposed as a means of 
 detecting its presence. Dr. Headland states (Action of Medi- 
 cine, p. 294), that the 3,000th part of a grain of the alkaloid, 
 dropped, in the form of solution, into the eye of an adult, will 
 
634 ATROPINE. 
 
 answer this purpose; and that one-tenth of a grain taken into 
 the stomach, will cause dilatation of both pupils. It must be 
 borne in mind, however, that this property is also possessed by 
 daturine and hyoscyamine, the former being 'the active principle 
 of stramonium, and the latter of henbane. 
 
 Separation from Organic Mixtures. 
 
 Suspected Solutions and Contents of the Stomach. — These 
 should first be carefully examined for the presence of any solid 
 portions of the plant or the seeds, which, if found, may be 
 identified by their physical and botanical characters. On ac- 
 count of the indigestible nature of the seeds and berries, they 
 may remain in the alimentary canal for some days without 
 undergoing any change. Dr. Christison cites several instances 
 (Op. Cit., p. 644) in which the seeds and fragments of the fruit 
 were discharged from the bowels and by vomiting, even several 
 days after they had been taken. 
 
 Atropine is separated with considerable difiiculty from com- 
 plex organic mixtures, especially when it exists in the form of 
 portions of the plant. The suspected mixture, after comminu- 
 tion of any solids present and dilution if necessary, is treated 
 with about an equal volume of strong alcohol, slightly acidulated 
 with sulphuric acid, and exposed for about half an hour to a 
 gentle heat ; when cool, the liquid portion is strained through 
 muslin, the residue washed with alcohol, and the strained liquid 
 and washings concentrated to a small bulk, at a moderate tem- 
 perature on a water-bath. If during the evaporation, much 
 insoluble matter separates, it is removed by a strainer. The 
 cooled concentrated liquid is passed through a moistened filter, 
 then transferred to a test-tube and washed by agitating it with 
 about twice its volume of pure ether, which, after repose, is 
 carefully decanted and reserved for future examination, if nec- 
 essary ; the aqueous solution may again be washed with a fresh 
 portion of ether, and this removed as before. The aqueous 
 liquid is now rendered slightly alkaline by potash, and thor- 
 oughly agitated with about twice its volume of pure chloroform, 
 which will dissolve the liberated alkaloid, if present ; after the 
 
SEPARATION FROM ORGANIC MIXTURES. 635 
 
 liquids have completely separated, the chloroform is carefully 
 removed to a large watch-glass, and allowed to evaporate spon- 
 taneously. 
 
 The residue, thus obtained in the watch-glass, is stirred 
 with a few grains of water, containing a trace of sulphuric acid, 
 and the solution, after filtration if necessary, examined by some 
 of the liquid tests for atropine. As the bromine test is much 
 the most characteristic yet known for the identification of this 
 alkaloid, it should first be applied to a single drop of the solu- 
 tion. If it should fail to produce a crystalline precipitate, it is 
 quite certain that neither of the other reagents would produce 
 crystals, without which the results are of little value, since 
 otherwise they are common to a large class of organic sub- 
 stances. It must not, however, be expected that the bromine 
 reagent wiU always produce a crystalline deposit containing all 
 the forms obtained from a perfectly pure solution of atropine ; 
 most frequently, under the present conditions, the precipitate 
 consists of short, opake, irregular needles, and granules, but 
 these are characteristic of the alkaloid. 
 
 In case the bromine reagent produces a precipitate which 
 will not crystallise, the remaining portion of the solution is 
 diluted with a small quantity of water, then rendered alkaline 
 by potash, and the alkaloid again extracted by chloroform. 
 This fluid may now, upon spontaneous evaporation, leave the 
 alkaloid, if present in very notable quantity, in the crystalline 
 state. The chloroform residue is dissolved in a few grains of 
 acidulated water, and examined as before directed. A small por- 
 tion of the solution may be submitted to the physiological test. 
 
 On applying the method now considered, to the examination 
 of the contents of the stomachs of inferior animals to which 
 comparatively small quantities of a fluid extract of belladonna 
 had been purposely added, we, in every instance, obtained per- 
 fectly satisfactory evidence of the presence of atropine. In 
 most of these cases, however, the results were quite doubtful, 
 until the second chloroform extract was examined, when the 
 bromine precipitate readily crystallised. 
 
 Atropine may also be recovered from organic mixtures by 
 the use of ether, the steps of the pr9cess being precisely the 
 
636 DATURINE. 
 
 same as when chloroform is employed. The alkaloid, however, 
 is much less readily extracted from organic liquids by ether 
 than by chloroform. 
 
 From the Blood. — Absorbed atropine may be recovered from 
 the blood, by acidulating the latter with sulphuric acid, in the 
 proportion of about one drop of the acid to each ounce of liquid, 
 and agitating it with something more than its own volume of 
 alcohol. The mixture is then gently heated for about fifteen 
 minutes, and the liquid, after cooling, strained through muslin, 
 and the residue washed with alcohol and strongly pressed. The 
 strained liquid is concentrated, at a moderate temperature on a 
 water-bath, again strained, then evaporated to a small volume, 
 filtered, rendered alkaline by potash, and the liberated alkaloid 
 extracted by chloroform. If the chloroform residue is not suffi- 
 ciently pure for testing, it is extracted, in the usual manner, a 
 second time by that liquid. 
 
 Three ounces of blood, taken from a dog that had been 
 given five drachms of Tilden's fluid extract of belladonna and 
 killed by a blow on the head one hour and a half afterwards, 
 when examined by the foregoing method, furnished very satis- 
 factory evidence of the presence of atropine. A similar quan- 
 tity of the extract being administered to a cat, a portion passed 
 into the lungs of the animal, and caused death in less than three 
 minutes. Five drachms of blood taken from this animal, also 
 furnished satisfactory and unequivocal evidence of the presence 
 of the alkaloid. 
 
 Section III. — Daturine. (Stramonium.) 
 
 History. — Daturine is the name applied to the active prin- 
 ciple, or alkaloid, of Thornapple, Jamestown weed, or Batura 
 stramonium. The existence of this principle was announced in 
 1819 by Brandes; but it was first obtained in 1833 by Geiger 
 and Hesse. It is found in all parts of the plant, but most 
 abundantly, it is said, in the seeds and fruit. Its elementary 
 composition, according to the analyses of Planta, is C34H23NO6, 
 it being identical with that of atropine. 
 
PHYSIOLOGICAL EFFECTS. 637 
 
 Preparation. — Daturine may be obtained from the bruised 
 seeds of stramonium, and other parts of the plant, in the same 
 manner as atropine is prepared from belladonna and its extract, 
 as heretofore described [ante, p. 622.) The proportion of the 
 alkaloid present in the plant, is, perhaps, about the same as 
 that found in belladonna. 
 
 Numerous instances of poisoning by stramonium more par- 
 ticularly by the seeds, have occurred, but, with few exceptions, 
 they have been the result of accident. As yet, there seems to 
 be no instance in which daturine in its pure state, has been 
 taken as a poison. 
 
 Symptoms. — The symptoms produced by stramonium are 
 very similar, if not identical in kind, with those occasioned by 
 belladonna. Thus, they are, dryness of the throat, difficulty of 
 deglutition, dilatation and insensibility of the pupil, headache, 
 nausea, vomiting, great thirst, obscurity of vision, or total 
 blindness, ringing in the ears, great anxiety, hot skin, flushed 
 countenance, vertigo, and wild delirium, with spectral illusions, 
 and tremors of the extremities, followed by stupor and coma. 
 Occasionally convulsions and paralysis have occurred, as also, 
 a scarlet eruption over the skin. 
 
 In a case reported by Dr. J. G. Johnson, of Brooklyn, 
 N. Y., a boy seven years of age, ate a quantity of the green 
 seeds of stramonium, picking them from the burs. The first 
 symptoms observed, were impaired speech, flushed face, twitch- 
 ings of the fingers, and a staggering gait. About two hours and 
 a half after taking the- poison, the child was in a state of violent 
 agitation, and had spasmodic twitchings of the hands, as if 
 affected with chorea; the pupils were enormously dilated, and 
 insensible to light, and there was total blindness; the face, 
 especially around the mouth, was much swollen, the action of 
 the heart feeble, and the pulse could not be counted; the lower 
 extremities were cold, and perfectly powerless. The action of 
 an emetic, now brought away a quantity of the seeds. Two 
 hours later, the child was violently maniacal, constantly catching 
 at imaginary objects in the air, was also deaf, and unable to 
 articulate. These symptoms gradually abated, but it was sev- 
 eral days before the patient entirely recovered, the insensibility 
 
638 DATURINE. 
 
 of the pupils continuing until the fourth day. (American Med. 
 Times, 1860, vol. i, p. 22.) 
 
 Dr. H. Y. Evans, of Philadelphia, has very recently re- 
 ported an instance in which seven children, aged from six to 
 nine years, had each swallowed, it is said, only ten of the seeds. 
 Four hours afterwards, the pupils in all seven cases were dilated 
 to their utmost. In three of the children, who had swallowed 
 the seeds without chewing them, dilatation of the pupils, and 
 slight perversion of vision, were the only effects observed. But 
 in the four remaining cases, in which the seeds had been 
 chewed, in addition to the dilated state of the pupils and per- 
 verted vision, there was confusion of intellect, deafness, intoxi- 
 cation, full pulse, slow respiration, and entire loss of power to 
 direct the motions of the limbs; these symptoms were succeeded 
 in a few hours by stupor, and in one case by violent delirium, 
 resembling delirium tremens. Emetics having failed to act, 
 except in the three slight cases, the stomach was emptied by 
 means of the stomach-pump, and on the third day every vestige 
 of the poisoning had disappeared, the pupils being the last to 
 yield. (Amer. Jour. Med. Sci., July, 1866, p. 278.) 
 
 A somewhat similar instance, to that just cited, has been 
 reported by Dr. A. P. Turner (Ibid., April, 1864, p. 552). Of 
 seven children who had eaten a quantity of the seeds, in five 
 of them vomiting was early produced, and they were but 
 slightly affected. In the other two, the most violent symptoms 
 with wild delirium manifested themselves; but iinder the use of 
 emetics, and laudanum, the patients were quite well on the 
 third day. In a case related by Dr. Calkins, a child four years 
 of age, entirely recovered after having swallowed over a table- 
 spoonful of the seeds, although they remained undisturbed in 
 the body for upwards of seven hours, when they were partly 
 ejected by vomiting, and afterwards partly by purging. (Ameri- 
 can Medical Monthly, Sept., 1856, p. 220.) 
 
 Dr. C. C. Lee has related an instance (Amer. Jour. Med. 
 Sci., Jan., 1862, p. 54) in which three adults were poisoned by 
 an alcoholic decoction of the seeds of stramonium. Soon after 
 taking the poison, two of the patients were speechless, unable 
 to walk, and in a comatose condition; their faces flushed to an 
 
PHYSIOLOGICAL EFFECTS. 639 
 
 almost violet hue, the conjunctivse injected, the pupils enor- 
 mously dilated and insensible, the face and upper extremities 
 burning hot, the tongue and throat dry, the respiration slow 
 and labored, and the pulse rapid, very tense and full. In the 
 other case, in which a smaller quantity of the decoction had 
 been taken, the skin was of a scarlet hue and hot, the pupils 
 dilated, the tongue parched, the respiration huri-ied, the pulse 
 very rapid, and fluttering, and there was intense thirst, with 
 violent delirium, the patient constantly pursuing, with her hands, 
 imaginary objects in the air, or picking at the bedclothes. 
 About an hour and a half after the poison had been taken, 
 active treatment, including the use of the stomach-pump, was 
 resorted to, under which all the patients rapidly recovered. 
 
 In a fatal case, quoted by Dr. Christison (On Poisons, p. 
 646), in which a child, aged two years, had swallowed, without 
 chewing, about one hundred of the seeds, the following symp- 
 toms were observed. The child soon became fretful and like a 
 person intoxicated; in the course of an hour efforts to vomit 
 ensued, together with flushed face, dilated pupils, incoherent 
 talking, and afterwards wild spectral illusions and furious delir- 
 ium. In two hours and a half, there was loss of voice and the 
 power of swallowing ; then croupy breathing and complete coma 
 set in, with violent spasmodic agitation of the limbs, occasional 
 tetanic convulsions, warm perspiration, and an imperceptible 
 pulse. Subsequently the pulse became extremely rapid, the 
 abdomen tympanitic, and the bladder paralysed, but there were 
 frequent involuntary stools; and death took place twenty-four 
 hours after the poison had been taken. At an early period in 
 the case, twenty of the seeds were discharged by an emetic; 
 and afterwards eighty by purging: none were found in the 
 alimentary canal after death. In another case, a decoction of 
 about one hundred and twenty-five of the seeds, proved fatal 
 to an elderly woman, in seven hours. In a case related by 
 Dr. Allan, an unknown quantity of the seeds caused the death 
 of a healthy man, in about seven hours and a half. (Lancet, 
 London, Sept. 18, 1847, p. 298.) 
 
 The external application of stramonium to a blistered sur- 
 face, has, in several instances, given rise to alarming symptoms. 
 
640 DATURINE. 
 
 In one instance, the extract employed as a suppository, induced 
 many of the symptoms of delirium tremens. Even bruising the 
 leaves in a mortar has caused dilated pupil and irritation of the 
 skin. (Beck's Med. Jur., vol. ii, p. 877.) 
 
 Treatment. — This is the same as in poisoning by bella- 
 donna (ante, p. 628). In a case of stramonium poisoning quoted 
 by Dr. A. StiUe (Mat. Med., vol. i, p. 754), one grain of chloride 
 of morphine was administered every hour, and eight grains were 
 taken before any result was perceived. After the eighth dose, 
 slight signs of awakening consciousness were visible, but the 
 pupil still remained widely dilated. Subsequently, as the symp- 
 toms abated, the intervals between the doses were lengthened, 
 but in the course of eighteen hours, fifteen grains of the mor- 
 phine salt were taken. 
 
 PoST-MOETEM ApPEAEANCES. — In the case of the child, here- 
 tofore cited, in which death occurred in twenty-four hours, the 
 brain was found natural, the stomach and intestines healthy, 
 the bladder distended, the larynx and oesophagus slightly red- 
 dened, the rima-glottidis thickened and very turgid, and the 
 blood throughout the body semi-fluid. In Dr. Allan's case, 
 nineteen hours after death, there was found great turgescence 
 of the membranes of the brain; the brain itself was firm and 
 highly injected, the choroid plexus turgid, and the ventricles 
 contained a little bloody serum. The lungs were very vascular, 
 and the heart flaccid. The stomach contained about four ounces 
 of ingesta, in which were found eighty-nine entire seeds of 
 stramonium, together with many fragments. The raucous mem- 
 brane of the stomach throughout was slightly congested, and 
 presented two patches of ex'travasation, the one being in the 
 greater curvature of the organ, and the otlier near the pyloric 
 orifice. Many of the poisonous seeds, as weU as fragments, 
 were also found throughout the entire length of the small 
 intestines. The liver, spleen, pancreas, bladder, and kidneys 
 were normal. 
 
 Chemical Peopeeties. 
 
 Daturine is not only identical with atropine in regard to its 
 elementary composition, but is also possessed, as first announced 
 
CHEMICAL PROPERTIES. 641 
 
 by Planta (See Chem. Graz., 1850, p. 350), of the same physical 
 and chemical properties. The chemical reactions of atropine 
 and the methods of separating it from organic mixtures, as 
 already described, are, therefore, equally applicable for the 
 detection of daturine. 
 
 On comparing the various reactions of two samples of datu- 
 rine — one prepared by Merck, and the other from a fluid ex- 
 tract of stramonium — with those of different samples of atropine, 
 we in no instance discovered any difference whatever. Thus, 
 solutions of daturine yielded with bromine, carbazotic acid, 
 chloride of gold, and with potash, precipitates, which assumed 
 the same crystalline forms as those, obtained from solutions of 
 atropine ; and the limits of the reactions, as also of the other 
 reagents for atropine heretofore described, were precisely the 
 same for both alkaloids. Moreover, the two bases appeared to 
 have the same degree of solubility in water, as also in chloro- 
 form, and in ether. 
 
 Taking these facts in connection with the similarity of the 
 physiological eflfects of atropine and daturine, there seems to be 
 no longer any doubt whatever of the entire identity of these 
 alkaloids ; or, in other words, that belladonna and stramonium 
 owe their activity to the presence of the same alkaloidal prin- 
 ciple. It is therefore obvious, that — unless some compound is 
 discovered to exist in the one that is not present in the other — 
 there can be no chemical means of distinguishing between pois- 
 oning by these plants ; and that this can only be done when 
 portions of the plant are found and identified by their physical 
 and botanical characters^ or by a knowledge of the attending 
 circumstances. 
 
 When one grain of daturine was dissolved, by the aid of a 
 •gentle heat, in four hundred grains of pure water, and the solu- 
 tion agitated with four volumes of chloroform, this liquid left 
 upon spontaneous evaporation 0'88 of a grain of the pure alka- 
 loid. When a similar aqueous solution was agitated with four 
 volumes of absolute ether, this fluid extracted 0'80 of a grain 
 of the alkaloid. On extracting alkaline complex organic mix- 
 tures containing small quantities of a fluid extract of stramo- 
 nium, by chloroform, we obtained about the same results as 
 
 41 
 
642 DATURINE. 
 
 already described from similar mixtures containing the extract 
 of belladonna. 
 
 One ounce of blood, taken from a cat killed by half an 
 ounce of Tilden's fluid extract of stramonium, when subjected 
 to the same treatment as described for the recovery of atropine 
 under similar circumstances, and the chloroform residue dis- 
 solved in two grains of water, gave, with the bromine test, per- 
 fectly unequivocal evidence of the presence of the alkaloid. 
 
VERATRINE. 643 
 
 CHAPTER Y. 
 
 VERATRINE, SOLANINE. 
 
 Section I. — Veratrine. (White Hellebore.) 
 
 History. — Veratrine is a powerfully poisonous alkaloid, found 
 in Veratrum album, or White hellebore, Veratrum viride, or 
 American hellebore, Veratrum sdbadilla, and in Sabadilla, the 
 seeds and fruit of Asagrcea officinalis. It was obtained from 
 sabadilla by Meissner, of Germany, in 1819, and about the 
 same time, from the same source, by Pelletier and Caventou, of 
 France; in 1820, the latter chemists obtained it from the rhi- 
 zoma of white hellebore, and in 1838, Mr. Worthington, of 
 Philadelphia, announced its existence in the root of Veratrum 
 viride. The identity of the alkaloidal principle of the latter 
 plant with that " of white hellebore, has been doubted ; but the 
 recent investigations of Mr. J. Gr. Richardson, and of Prof. S. 
 R. Percy, as well as of Mr. G. J. Scattergood, seem to leave no 
 doubt of the identity of these principles. The composition of 
 veratrine, in its pure crystalline state, according to G. Merck, 
 is C64H52N2O16. 
 
 Preparation. — For commercial purposes, veratrine is usually 
 obtained from the seeds of sabadilla, or cevadilla, as it is fre- 
 quently called. The bruised seeds, deprived of their capsules, 
 are exhausted by repeated portions of hot alcohol, the mixed 
 alcoholic solutions concentrated to a small volume, then treated 
 with slight excess of ammonia, and the impure precipitated 
 alkaloid washed with cold water ; it is then boiled for some little 
 time with water acidulated with hydrochloric acid and contain- 
 ing animal charcoal, the cooled solution filtered, the concen- 
 trated filtrate rendered slightly alkaline by ammonia, the pre- 
 cipitate thus produced washed with water, and then dried on a 
 
644 VERATRINE. 
 
 water-bath. The product thus obtained may be further purified 
 by dissolving it in water acidulated with hydrochloric acid, and 
 extracting the foreign organic matter by ether ; after decanting 
 this liquid, the aqueous solution is treated with slight excess of 
 ammonia, and the liberated alkaloid extracted by fresh ether, 
 which is allowed to evaporate" spontaneously, when the veratrine 
 will be left in its very nearly pure, but amorphous or, at most, 
 granular state. 
 
 Instead of the use of alcohol for the extraction of the alka- 
 loid from the bruised seeds, Dr. Thomson, of Edinburgh, has 
 proposed to treat them with boiling water acidulated with hydro- 
 chloric acid, and allow the whole to stand twenty-four hours. 
 The liquid is then expressed, filtered, concentrated to a small 
 volume, and treated with slight excess of ammonia. The pre- 
 cipitate thus produced is collected on a filter, washed, and dried, 
 then pulverised and extracted with hot alcohol. The alcoholic 
 solution is distilled, until the spirit is entirely expelled, the res- 
 idue heated with acidulated water and animal charcoal, and the 
 filtered solution rendered slightly alkaline by ammonia, when 
 the veratrine will be precipitated in the form of a nearly pure- 
 white powder. (Chemical News, June 1, 1861, p. 334.) By 
 this method, Dr. Thomson obtained at the rate of twenty grains 
 of the alkaloid from one avoirdupois pound of the seeds. From 
 one pound, avoirdupois, of the dried root of Veratrum viride, 
 Mr. Gr. J. Scattergood, of Philadelphia, states that he obtained 
 about thirty grains of the nearly pure alkaloid. 
 
 Gr. Merck obtained veratrine in the crystalline state by mak- 
 ing a dilute solution of the commercial alkaloid in alcohol con- 
 taining as much water as possible, without precipitating the 
 alkaloid, and evaporating the solution on a water-bath at a 
 gentle heat, during which a portion of the veratrine separated 
 in the form of a white crystalline powder mixed with brown 
 resinous matter. The latter was separated by washing the mix- 
 ture with cold alcohol. On dissolving the crystalline residue in 
 highly-rectified alcohol, and allowing the liquid to evaporate 
 spontaneously, the alkaloid was left in the form of rhombic 
 prisms, of about half an inch in length. (Chemical Gazette, 
 1855, p. 426.) 
 
PHYSIOLOGICAL EFFECTS. 645 
 
 Poisoning by veratrine, in its pure state, has been of ex- 
 tremely rare occurrence, and as yet in no instance, so far as 
 we know, has it been taken in fatal quantity by the human 
 subject. But poisoning by portions of some of the different 
 plants which owe their activity to the presence of this alkaloid, 
 has not unfrequently happened, as the result of accident. There 
 seems to be no instance on record of criminal poisoning by this 
 substance. The ordinary medicinal dose of the commercial 
 alkaloid is about one-tenth of a grain. 
 
 Symptoms. — White hellebore root has long been known as a 
 poison. When taken in poisonous quantity, the more usual 
 effects are, a sense of burning heat in the stomach, with a feel- 
 ing of constriction and heat in the mouth and throat, great 
 anxiety, nausea, violent vomiting, purging, tenesmus, pain in 
 the bowels, trembling of the limbs, great prostration, cold sweats, 
 small and feeble pulse, vertigo, dilated pupils, loss of sight, im- 
 paired speech, coldness of the extremities, convulsions, and 
 insensibility. These symptoms are never, perhaps, all present 
 in the same case. Thus instances are recorded in which purg- 
 ing was absent, and others in which there was no vomiting. 
 This substance has not unfrequently occasioned death. In 
 non-fatal cases, the symptoms are sometimes very slow in dis- 
 appearing. 
 
 In an instance cited by Dr. Christison, in which three per- 
 sons had taken a quantity of the root, and finally recovered, 
 the following symptoms were observed. In the course of an 
 hour all the patients experienced a sense of burning in the 
 throat, guUet, and stomach, followed by nausea, dysuria, and 
 vomiting ; weakness and stiffness of the limbs ; giddiness, blind- 
 ness, and dilated pupil ; great faintness, convulsive breathing, 
 and small pulse. One of them, an elderly woman, who had 
 taken the largest quantity, had an imperceptible pulse, stertor- 
 ous breathing, and total insensibility ; on the following day, an 
 eruption appeared over the body. (On Poisons, p. 673.) Two 
 children, aged three and a half and one and a half years 
 respectively, drank of a decoction of white hellebore. The 
 principal symptoms were violent vomiting, insensibility, a pale 
 and sunken countenance, small sharp pulse, heat of head and 
 
646 VERATRINE. 
 
 coolness elsewhere, slight spasmodic movements of the face and 
 limbs, neck somewhat swollen, deglutition impossible, pupils di- 
 lated, and the eyes staring. Both children recovered. (Still^'s 
 Mat. Med., vol. ii, p. 314.) 
 
 In a fatal case, in which a man had taken only a small 
 quantity of the powdered root, the patient was soon seized with 
 violent and incessant vomiting, and died within twelve hours. 
 In an instance quoted by Dr. Taylor (On Poisons, p. 575), 
 twenty grains of the powder caused convulsions, and death in 
 three hours. The external application of hellebore to the epi- 
 gastrium has caused violent vomiting. So, also, its employment 
 in the form of enema, has given rise to violent symptoms. 
 
 American hellebore, familiarly known as Indian poke, has 
 not unfrequently produced alarming, and even, at least in one 
 instance, fatal results. AU parts of the plant have a nauseous, 
 bitter taste, followed by a persistent acrid sensation in the mouth 
 and throat. The symptoms occasioned by an overdose of this 
 substance are very similar to those produced by white hellebore. 
 In a case reported by Dr. J. C. Harris, of West Cambridge, 
 a feeble child one and a half years old, was ignorantly given 
 four drops of the tincture of veratrum viride mixed with water, 
 every half hour, until four or five doses had been taken, when 
 by mistake a dose containing about sixteen drops was adminis- 
 tered. Eepeated efforts to vomit ensued after the administration 
 of the second dose, but without success, except once, when a 
 small quantity of matter was ejected from the mouth. Seven 
 hours after taking the first dose, the child was apparently un- 
 conscious, very^ pale, and breathing stertorously ; the pulse, was 
 very slow, the extremities cold, and a profuse perspiration cov- 
 ered the whole body. Treatment was now resorted to, but 
 without any attempt to remove the contents of the stomach. 
 The symptoms increased in violence, and death ensued in about 
 thirteen hours after the first dose had been given. ' (Amer. 
 Jour. Med. Sci., July, 1865, p. 284.) 
 
 Dr. T. M. Johnson, of Buffalo, has very recently related an 
 instance in which he made a post-mortem examination of the 
 body of a woman whose death was claimed to have been pro- 
 duced by two doses of Tilden's fluid extract of veratrum viride. 
 
PHYSIOLOGICAL EFFECTS. 647 
 
 It seems that the woman, who was fifty years old and quite 
 infirm, had taken at first a dose of about thirty drops of the 
 extract, and in about two hours was seized with considerable 
 pain in the stomach, nausea, and vomiting. From four to six 
 hours after taking the first dose she took another, and larger 
 one, probably about forty-five drops. This was followed within 
 two hours by severe pain in the epigastrium, retching, vomit- 
 ing, weak and rapid pulse, and marked prostration ; and within 
 twelve hours, she had two or three bloody stools with consider- 
 able tenesmus. Diarrhoea continued a few hours after the sub- 
 sidence of the dysenteric discharges ; but the retching and 
 vomiting continued at intervals for about four weeks, when she 
 died. No abnormal appearance was detected in the body, ex- 
 cepting that the stomach was much less in size than usual. 
 (Buffalo Med. and Surg. Jour., Nov., 1866, p. 133.) 
 
 In an instance related by Dr. J. B. Buckingham, two gen- 
 tlemen, through mistake, swallowed each about a teaspoonful of 
 a fluid extract of the American hellebore. In about half an 
 hour one of the patients was found almost speechless, retching 
 and vomiting incessantly,^ bathed in profuse cold perspiration, 
 and with a scarcely perceptible pulse. On the administration 
 of a teaspoonful of laudanum, the vomiting ceased, and the 
 patient rapidly recovered. In the other case, in which the 
 laudanum was not administered, the vomiting continued for 
 some hours, with total loss of speech and of locomotion for 
 some time. (Amer. Jour. Med. Sci., Oct., 1865, p. 563.) A 
 case is reported in which an ointment of veratrum viride applied 
 to an ulcer on the leg, produced vomiting. 
 
 Veratrine, as found in the shops, is subject to great variation 
 in strength. In a case communicated to Dr. Taylor, one six- 
 teenth of a grain of the alkaloid nearly proved fatal to a lady. 
 Not long after the dose had been taken, the patient was found 
 insensible, the surface cold, the pulse failing, and there was 
 every symptom of approaching dissolution. (On Poisons, p. 
 576.) In a case mentioned by Dr. S. R. Percy, a physician 
 took, by mistake, thirty grains of the crude alkaloid prepared 
 from veratrum viride. It caused copious vomiting, followed by 
 prostration and loss of pulse at the wrist; but under the free 
 
648 VERATRINE. 
 
 use of stimulating remedies, the patient entirely recovered on 
 the third day. (Prize Essay, 1864, p. 76.) 
 
 Two grains of nearly colorless commercial veratrine being 
 administered in solution to a healthy cat, the animal was imme- 
 diately rendered prostrate, frothed at the mouth, and died in 
 less than one minute after taking the dose. A similar quantity 
 given to a second cat, produced similar symptoms, and death 
 in one minute and three-quarters. Three grains of the same 
 preparation given to a young dog, caused immediate vomiting, 
 which was frequently repeated, with pui-ging, involuntary urina- 
 tion, and great prostration, followed by death in two hours after 
 the administration of the dose. Of another sample of the com- 
 mercial alkaloid, two grains each were given to two small dogs, 
 without producing any appreciable symptom other than slight 
 prostration, from which the animals soon recovered. 
 
 Teeatment. — This consists in the speedy removal of the 
 poison from the stomach, and the subsequent exhibition of 
 stimulants. Opium has in several instances been found highly 
 beneficial. No chemical antidote is as yet known. Vegetable 
 infusions containing tannic acid have been strongly advised. 
 Although this vegetable acid forms with veratrine a compound 
 that is only very sparingly soluble in water, yet it is very 
 readily soluble in the presence of a free acid. In some instances 
 purgatives may be found highly useful. 
 
 PoST-MOETEM AppEAEANCES. — In the few cases that have 
 been examined, in death from this substance, the alimentary 
 canal was more or less inflamed; but nothing has been observed 
 characteristic of the action of the poison. In animals killed by 
 commercial veratrine, Esche found the throat and oesophagus 
 pale; the stomach and bowels more or less contracted, and the 
 latter somewhat reddened ; and the lungs, liver, and heart gorged 
 with blood. The brain presented nothing abnormal. (Stille's 
 Mat. Med., yol. ii, p. 312.) 
 
 Chemical Peopeeties. 
 
 In the Solid State. — Veratrine, when perfectly pure, is a 
 colorless, odorless solid, which may be obtained, not however 
 
CHEMICAL PROPERTIES. 649 
 
 without considerable difficulty, in the form of transparent crys- 
 talline prisms. It has an exceedingly acrid, but not bitter 
 taste, followed by a persistent sense of dryness and acridity 
 in the fauces. When snuifed into the nostrils, even in only 
 very minute quantity, it occasions most violent and prolonged 
 sneezing. As found in the shops, veratrine is usually in the 
 form of a dull-white or yellowish-white amorphous powder, 
 having an intensely acrid, with a more or less bitter taste. 
 The impure alkaloid is much more apt, on handling, to become 
 diffused in the air and excite sneezing than the pure base. 
 
 When applied, in the form of an alcoholic solution, to the 
 sound skin, veratrine occasions a sense of heat, redness, and 
 pricking in the part. Heated on porcelain or in a glass tube, 
 the pure alkaloid fuses to a brownish transparent liquid, swells 
 up, and is slowly dissipated, under decomposition, without any 
 residue; heated in a direct flame, it takes fire and burns with 
 dense smoke. Its fusing point, according to Couerbe, is 239? F. 
 
 If a small quantity of pure veratrine be touched with a 
 drop or two of cold concentrated sulphuric acid, it assumes a 
 yellow color, then a reddish tint, and slowly dissolves to a 
 pinkish solution, which after several minutes acquires a deep 
 crimson-red color. These changes are brought about almost 
 immediately by the application of heat. This is one of the 
 most characteristic reactions of veratrine yet known (see post). 
 
 Concentrated hydrochloric acid dissolves the pure alkaloid 
 without change of color; but if the solution be heated to the 
 boiling temperature, as first observed by Merck and recently 
 more minutely by Trapp of St. Petersburg, it quickly acquires 
 a red color, which ultimately becomes very intense and resem- 
 bles that of a solution of permanganate of potash. Under this 
 reaction, if only a drop of the acid be employed, almost the 
 least visible quantity of the alkaloid will manifest itself. With 
 minute quantities, the coloration is best observed b,y performing 
 the experiment in a white porcelain dish. 
 
 The pure alkaloid is also soluble without change of color in 
 concentrated nitric acid. But, under the action of this acid, 
 the alkaloid as found in the shops, usually acquires a yellow or 
 reddish color and dissolves to a more or less yellowish solution. 
 
650 VERATRINE. 
 
 Veratrine has strong basic properties completely neutralising 
 even the most powerful aeids to form salts, but few of which 
 have as yet been obtained in the crystalline state. The sul- 
 phate, chloride, tartrate, and oxalate are said to have been 
 thus obtained. Merck, however, failed to obtain the sulphate 
 and chloride in the crystalline form; but he obtained the crys- 
 tallised double salts of the alkaloid and perchloride of mercury, 
 and of terchloride of gold. We, also, have obtained these 
 double salts, as well as the simple bromide, in this state. The 
 uncrystallisable salts form colorless gum-like masses. All the 
 salts of veratrine have the intensely acrid taste of the pure 
 alkaloid. 
 
 Solubility. — When large excess of pure veratrine was di- 
 gested for several hours, with frequent agitation, in pure water 
 at the ordinary temperature, one part of the alkaloid dissolved 
 in about 7,860 parts of the liquid. Absolute ether, under the 
 foregoing conditions, dissolved the pure alkaloid in the propor- 
 tion of one part in 108 parts of the fluid. It is very freely 
 soluble in chloroform, and also in alcohol. The solubility of 
 commercial veratrine in these different liquids, is subject to 
 great variation. The alkaloid is readily soluble in water con- 
 taining a free acid; but it is only very sparingly soluble in the 
 caustic alkalies. 
 
 One grain of pure veratrine was dissolved by the aid of 
 just sufficient hydrochloric acid, in one hundred grains of water, 
 the solution rendered slightly alkaline by potash, and the gelat- 
 inous mixture violently' agitated with an equal volume of pure 
 ether; this liquid was then separated and allowed to evaporate 
 spontaneously, when it left a transparent vitreous residue of 
 0'89 of a grain of the pure alkaloid. Chloroform, under sim- 
 ilar conditions extracted 0'98 of a grain of the alkaloid, which 
 it left on spontaneous evaporation, in the form of a transparent 
 glacial mass, easily pulverisable to a highly electrical powder. 
 
 The salts of veratrine are, for the most part, freely soluble 
 in water, but insoluble, or very nearly so, in ether; they are 
 somewhat soluble in chloroform. When one grain of the alka- 
 loid in the form of chloride, is dissolved in one hundred grains 
 of water, and the solution agitated with an equal volume of 
 
POTASH AND AMMONIA TESTS. 651 
 
 pure ether, this fluid extracts 0'03 of a grain of the salt. 
 Under similar conditions, chloroform extracts 0'31 of a grain of 
 the salt, which it leaves, on spontaneous evaporation, in the 
 form of a colorless, vitreous mass. 
 
 Of Solutions of Veeatrine. — In the following examina- 
 tion of the behavior of solutions of veratrine, as well as in the 
 preceding investigations, a perfectly colorless and partly crys- 
 talline sample of the alkaloid was employed. It was obtained 
 by dissolving colorless amorphous veratrine in water by the aid 
 of hydrochloric acid, treating the solution with slight excess 
 of caustic potash, extracting the precipitated alkaloid with chlo- 
 roform, allowing this liquid to evaporate spontaneously, dis- 
 solving the residue in alcohol, and exposing the solution to slow 
 evaporation. The solutions, employed in the following experi- 
 ments, were prepared by dissolving the purified alkaloid in pure 
 water, by the aid of the least possible quantity of hydrochloric 
 acid. The fractions employed, indicate the fractional part of a 
 grain of the anhydrous alkaloid present in one grain of the 
 liquid; the results, unless otherwise indicated, refer to the 
 behavior of one grain of the solution. 
 
 1. Potash and Ammonia. 
 
 The caustic alkalies, as well as their protocarbonates, throw 
 down from solutions of salts of veratrine, when not too dilute, 
 a white amorphous precipitate of the free alkaloid, which is 
 only sparingly soluble in excess of the precipitant, but readily 
 soluble in diluted acetic acid. After a time, especially if the 
 mixture be stirred, the precipitate becomes more or less granular. 
 1- Too' grain of veratrine, in one grain of water, yields a very 
 
 copious precipitate, which, after a little time, becomes 
 
 converted into small granules. 
 
 2. 1,0 grain, yields a very good precipitate, which is readily 
 
 soluble, to a clear solution, in excess of the precipitant. 
 
 3. 5 /000 grain: if only a mere trace of the reagent be added, 
 
 the mixture becomes distinctly turbid; if a larger quan- 
 tity of the precipitant be employed, the alkaloidal solution 
 remains clear. 
 
652 VERATRINE. 
 
 The true nature of the precipitate produced by these re- 
 agents may be established by the following test. 
 
 2. Sulphuric Acid. 
 
 The colorless salts of veratrine, as well as the free alkaloid, 
 when treated in the dry state with concentrated sulphui'ic acid, 
 slowly dissolve to a reddish-yellow or pinkish solution, which 
 after some minutes acquires a deep crimson-red color. If the 
 mixture be gently heated, this color manifests itself within a 
 few moments, and remains unchanged for some hours. The 
 color is slowly destroyed by the prolonged action of heat, and, 
 also, by stirring in the mixture a small crystal of bichromate 
 of potash. 
 
 The following quantities of the alkaloid were obtained by 
 evaporating one grain of a corresponding solution of the chloride 
 to dryness on a water-bath. 
 
 1. y^ grain of veratrine, when gently warmed with a drop of the 
 
 acid, quickly dissolves to a magnificent crimson solution. 
 
 2. 1,000 grain, yields much the same results as 1. 
 
 3. 10.0 grain : if the veratrine deposit be first gently warmed, 
 
 and then a small drop of the, acid be allowed to flow over 
 it, the heat being continued, it almost immediately assumes 
 a deep red color, and quickly dissolves to a solution hav- 
 ing a quite distinct red hue. 
 
 4. 5 0,0 grain : when treated as under 3, the deposit assumes 
 
 a faint reddish tint, and dissolves to a colorless solution. 
 
 Even a much less quantity of the alkaloid than the last- 
 mentioned, if collected at one point and touched with a minute 
 drop of the warmed acid, will yield a very distinct coloration. 
 
 Fallacies. — It has been objected to this test, that several 
 other organic substances also strike a red color with sulphuric 
 acid. But, unless the mixture be heated immediately after the 
 application of the acid, these objections have no force, since all 
 these substances, unlike veratrine, are immediately colored by 
 the cold acid. Moreover, the colors thus produced differ in tint 
 from that occasioned, even after some minutes, by veratrine. 
 And, furthermore, under the continued action of the acid and 
 
CHLORIDE OF GOLD TEST. 653 
 
 heat, they differ greatly from the alkaloid under consideration. 
 The exact behavior of the more prominent of these fallacious 
 substances may be briefly mentioned. 
 
 Narceine, when touched with the cold acid, immediately as- 
 sumes a brown color, which quickly changes to brownish-yellow, 
 then slowly to greenish-yellow ; if the mixture be gently heated, 
 the narceine quickly dissolves to a bright, brownish-red solution, 
 which, upon continuation of the heat, darkens in color and finally 
 becomes dark purple red. Solanine, under the action of the 
 cold acid, immediately assumes an orange-brown color, and very 
 slowly dissolves to an orange solution, which, after some hours, 
 acquires a purplish-brown color and yields a brownish precipi- 
 tate ; if the orange colored solution be heated, it soon darkens, 
 becoming almost black. Piperine acquires with the acid an 
 immediate orange-red color, which soon becomes brown ; if the 
 mixture be heated, it immediately assumes a very dark brown 
 color. Salacine imparts to the acid an immediate crimson-pink 
 hue, which, on the application of a gentle heat, is increased 
 in intensity, then darkens, and finally becomes almost black. 
 Papaverine dissolves in the acid to an immediate purple solu- 
 tion, the color of which soon fades ; on heating the mixture, 
 the color is quickly discharged. 
 
 It must be remembered that the intensity of the color pro- 
 duced by veratrine and sulphuric acid, may be more or less 
 modified by the presence of foreign matter; and that this is, 
 perhaps, never wholly absent when the alkaloid is extracted in 
 the ordinary manner from complex organic mixtures. 
 
 3. Chloride of Gold. 
 
 Terchloride of gold produces in solutions bf salts of veratrine 
 a canary-yellow amorphous precipitate, which is very sparingly 
 soluble, without darkening, in caustic potash ; it is also only 
 sparingly soluble in acetic and hydrochloric acids. Upon 
 boiling the mixture containing the precipitate, the latter dis- 
 solves, but is redeposited unchanged, as the liquid cools. The 
 precipitate is readily soluble in alcohol, from which on slow 
 evaporation, it separates in the form of beautiful groups of 
 
654 VERATRINE. 
 
 yellow, silky crystals, having, according to Gr. Merck, the for- 
 mula C64H52N2O,; HCl, AUCI3. 
 
 !• Too" grain of veratrine, in one grain of water, yields a very 
 copious precipitate. If the precipitate from a few grains 
 of the alkaloidal solution be dissolved in a few drops of 
 alcohol, and the alcoholic solution be allowed to slowly 
 evaporate, it soon deposits very delicate crystalline tufts, 
 and granules, Plate XIII, fig. 3. The formation of these 
 crystals, however, is readily prevented by the presence of 
 foreign matter. 
 
 2. rrroo grain, yields a quite good deposit, which is readily solu- 
 
 ble, to a colorless solution, in a few drops of caustic potash, 
 but only slowly soluble in large excess of hydrochloric acid. 
 
 3. 10,0 grain, yields a very distinct precipitate, which is 
 
 readily soluble by heat, but reproduced as the mixture 
 cools. 
 
 4. s'0,000 grain: the mixture becomes distinctly turbid. 
 
 4. Bromine in JBromohydric Acid. 
 
 An aqueous solution of bromohydric acid saturated with 
 bromine, occasions in solutions of salts of veratrine, and aqueous 
 solutions of the free alkaloid, even when highly diluted, a per- 
 manent, yellow, amorphous precipitate, which is only sparingly 
 soluble in diluted acetic and hydrochloric acids. The precip- 
 itate is readily decomposed by caustic potash. Alcohol dissolves 
 it readily, and on spontaneous evaporation leaves it in the form 
 of groups of bold prismatic crystals. 
 
 1. YoTT grain of veratrine, in one grain of water, yields a very 
 
 copious, bright-yellow precipitate, the color of which, on 
 the addition of potash, becomes white. The precipitate, 
 when dissolved in alcohol and the liquid allowed to evap- 
 orate spontaneously, yields a very good crystalline deposit, 
 Plate XIII, fig. 4. 
 
 2. 1,000 grain, yields a dirty-yellow precipitate, which is readily 
 
 soluble, to a clear solution, in potash. If the precipitate 
 be dissolved in alcohol and the liquid evaporated sponta- 
 neously, the deposit is left in the crystalline form. 
 
IODINE IN IODIDE OF POTASSIUM TEST. 655 
 
 3. 10,0 grain, yields a greenish-yellow precipitate. 
 
 ^' 5o,oo "o grain : a quite distinct^ deposit. 
 
 5. 1 o!o o 'o grain, yields a very perceptible turbidity. 
 
 5. Iodine in Iodide of Potassium. 
 
 An aqueous solution of iodide of potassium containing free 
 iodine, throws down from solutions of veratrine, and of its salts, 
 a permanent, amorphous precipitate, which is soluble in alcohol, 
 but only sparingly soluble in acetic and hydrochloric acids. 
 The exact color of the precipitate is determined by the quan- 
 tity of the alkaloid present. 
 
 1. YFo grain of veratrine, yields a very copious, reddish-brown 
 
 precipitate, which, upon the addition of potash, assumes a 
 white color. 
 
 2. i.o'oo grain : a copious deposit, which is readily soluble, to a 
 
 clear solution, in caustic potash. 
 
 3. lo ' .ooo grain, yields a good, reddish-yellow precipitate. 
 
 4. 5 0,0 grain: a distinct, greenish-yellow deposit. 
 
 5- ioo%o "o grain, yields a quite perceptible cloudiness. 
 
 6. Carbazotic Acid. 
 
 An alcoholic solution of carbazotic acid produces in solutions 
 of salts of veratrine, when not too dilute, a yellow amorphous 
 precipitate, which is soluble in alcohol and in free acids, even 
 acetic acid. 
 !• TTo grain of veratrine, in one grain of water, yields a very 
 
 copious deposit. 
 2- i7^"o grain: a quite good, greenish-yellow precipitate. 
 3. 5,000 grain, yields a quite distinct turbidity. 
 
 7. Bichromate of Potash. 
 
 This reagent throws down from concentrated solutions of salts 
 of veratrine a yellow amorphous precipitate, which is insoluble 
 in excess of the precipitant, and only sparingly soluble in di- 
 luted acids. The precipitate is readily soluble in strong alcohol. 
 
656 VERATRINE. 
 
 !• To~o^ grain of veratrine, yields a quite good precipitate, which 
 
 after a time becomes more or less granular. 
 2. ToT grain, yields a very distinct reaction. 
 3- r.W5 grain: no indication. 
 
 Ghromate of potash produces a precipitate similar to that 
 occasioned by the bichromate, but the reaction is somewhat less 
 delicate. 
 
 Other Reagents. — Sulphocyanide of potassium, and iodide of 
 potassium throw down from concentrate solutions of salts of the 
 alkaloid white amorphous precipitates, which are readily soluble 
 in acetic acid. Bichloride of platinum, and ferricyanide of po- 
 tassium occasion in similar solutions, dirty-yellow precipitates. 
 Ferrocyanide of potassium fails to produce a precipitate. Cor- 
 rosive sublimate throws down from very concentrated solutions, 
 a white amorphous deposit, which is readily soluble in water, 
 and left, on slow evaporation of the liquid, in the crystalline 
 state. Tannic acid occasions a white flocculent precipitate, even 
 in highly diluted solutions of the alkaloid. 
 
 Separation from Organic Mixtures. 
 
 Veratrine may be separated from complex organic mixtures, 
 as the contents of the stomach, and from the blood, in pre- 
 cisely the same manner as already pointed out for the recovery 
 of atropine from similar mixtures (see ante, p. 634). A portion 
 of the residue thus obtained from the chloroform extract, is 
 examined by the sulphuric acid test, in the manner already 
 indicated. Another portion may be heated with concentrated 
 hydrochloric acid. Any remaining portion may then be dis- 
 solved in a small quantity of water, containing a trace of acetic 
 acid, and the solution, after filtration if necessary, examined by 
 some of the liquid tests. Should the chloroform residue contain 
 much foreign matter, it may be purified by dissolving it in acid- 
 ulated water, rendering the filtered solution alkaline with potash, 
 and again extracting the liberated alkaloid by chloroform. 
 
 On examining, after the method just recommended, the 
 contents of the stomach of the first cat, heretofore mentioned. 
 
SOLANINE. 657 
 
 which had been killed in less than one minute by two grains 
 of veratrine, and, also, of the young dog, killed in two hours 
 by three grains of the alkaloid, we, in both instances, recovered 
 very notable quantities of the poison. 
 
 One fluid ounce of hlood, taken from the cat just alluded to, 
 gave, when the chloroform residue was treated with sulphuric 
 acid, very satisfactory evidence of the presence of the alkaloid. 
 This case shows the great rapidity with which the poison may 
 enter the circulation. No part of the second cat, before re- 
 ferred to, was chemically examined. The residue from six fluid 
 drachms of blood from the young dog, when examined by sul- 
 phuric acid, gave perfectly unequivocal evidence of the presence 
 of the poison, the coloration being about as well-marked as 
 from any quantity of the pure alkaloid. 
 
 Section II. — Solanine. (Nightshade.) 
 
 History. — Solanine, or solania, is the name given to a poi- 
 sonous alkaloid found in Solanum dulcamara, or Woody-night- 
 shade, Solanum nigrum, or Grarden-nightshade, and in several 
 other species of the solanum genus of plants. It was first 
 discovered, in 1821, by M. Desfosses, in the solanum nigrum. 
 Blanchet assigned to it the formula CgiHsgNOas; but according 
 to the more recent analysis of M. Moitessier, it consists of 
 C42H35NO14. Still more recently. Otto Grmelin has stated that 
 the alkaloid is destitute of nitrogen, its composition being, 
 perhaps, CssHyjOso. (Chemical Q-azette, vol. xvii, p. 385.) 
 
 Preparation. — Solanine is most readily obtained, according 
 to M. Wackenroder, from the apples of the common potato, 
 Solunum tuberosum. The slightly crushed apples are covered 
 in a suitable vessel for about fifteen hours with water containing 
 sufficient sulphuric acid to give the mixture a strongly acid 
 reaction. They are then expressed and removed, and the 
 turbid acid liquid, with fresh portions of sulphuric acid, added 
 to two successive quantities of fresh apples, and these macerated 
 and removed as before. The liquid is now allowed to stand 
 some days, then strained through linen, and treated with slight 
 
 42 
 
658 SOLANINE. 
 
 excess of powdered hydrate of lime. After about twenty-four 
 hours, the lime precipitate, containing the solanine, is collected 
 on a linen strainer, dried in warm air, and boiled several times 
 with successive portions of strong alcohol, which will extract 
 the alkaloid. The united alcoholic extracts are then heated 
 and, M'hile hot, filtered; on cooling, the liquid will deposit most 
 of the alkaloid, partly in the form of crystalline laminae and 
 scales. (Ibid., vol. i, p. 325.) 
 
 By dissolving ordinaiy solanine in water by the aid of 
 hydrochloric acid, precipitating by ammonia, and frequent re- 
 crystallisation from nearly absolute alcohol, Otto Gmelin ob- 
 tained the alkaloid in the form of beautiful, colorless, silky 
 needles of considerable length. 
 
 Some of the plants which owe their activity, principally, if 
 not entirely, to the presence of this alkaloid, have in several 
 instances occasioned death; but we are not aware of any 
 instance of poisoning, in the human subject, by the prepared 
 alkaloid. 
 
 Symptoms. — Solatium dulcamara, or Bittersweet, when taken 
 in an overdose, may give rise to dryness of the mouth and 
 throat, thirst, nausea, headache, vertigo, vomiting, purging, and 
 convulsions, followed in some instances by death. A little boy, 
 aged four years, who had eaten at least two of the berries of 
 this plant, was seized about fifteen hours afterwards, with purg- 
 ing and vomiting, and subsequently with convulsions, which 
 continued during the day, leaving the child comatose and insen- 
 sible during the intervals. Vomiting of bilious matters, having 
 a dark-greenish color, continued, and during the evening the 
 convulsions became permanent, and death ensued in about thirty- 
 two hours after the poison had been taken. A sister of the 
 deceased, aged six years, who had eaten only a single beiTy, 
 was seized with sickness and purging, from which, however, 
 she recovered without more serious efi^ects. Another sister, 
 still two years older, who had eaten two of the berries, escaped 
 without any marked symptom. (Lancet, London, June 28, 
 1856, p. 715.) In two other cases, an unknown number of the 
 berries proved fatal to two children. In an instance cited by 
 Dr. Beck (Med. Jur., vol. ii, p. 825), several children who had 
 
PHYSIOLOGICAL EFFECTS. 659 
 
 eaten some of the berries, were seized with violent pain in the 
 intestines, vomiting and purging, and in one instance, a profuse 
 secretion of saliva. Under active treatment they all recovered. 
 
 So, also, the Solanum nigrum has in several instances de- 
 stroyed life. Two little girls, between three and four years of 
 age, ate a quantity of the leaves of this plant. Between two 
 and three hours afterwards they were both seized with pain in 
 the bowels, vomiting, great uneasiness, picking at the bed- 
 clothes, and delirium. On the succeeding day, one of the chil- 
 dren, which had suffered for several days from relaxed bowels, 
 presented the following symptoms : the abdomen was much 
 swollen, the pulse very frequent and scarcely perceptible; the 
 respiration was quiet, the face pale, the pupils strongly dilated, 
 and there was great uneasiness of the body, picking at the 
 bedclothes, and entire loss of consciousness. Notwithstanding 
 active treatment, the child died, under extreme exhaustion, 
 during the evening of the same day. The other child entirely 
 recovered on the second day. (Med.-Chir. Rev., Am. ed., Oct., 
 1860, p. 380.) 
 
 In an instance quoted by Orfila (Toxicologic, 1852, i, 313), 
 three children who had eaten the berries of the Garden-night- 
 shade, were seized with severe headache, nausea, vertigo, colic, 
 tenesmus, and copious vomiting. In one of the children, these 
 symptoms were succeeded by extreme dilatation of the pupils, 
 impaired vision, flushed facej profuse sweating, intense thirst, 
 loss of voice, stertorous breathing, and tetanic convulsions, 
 followed by death in about twelve hours after the berries had 
 been eaten. The two other children, after suffering much the 
 same symptoms, almost entirely recovered; but they had a 
 relapse, under which they finally sunk. 
 
 Mr. Morris, of Merford, has related an instance in which a 
 young lady, aged fourteen years, died from the effects of eating 
 the berries of the Solanum tuberosum, or common potato plant. 
 The symptoms described were, great jactitation, lividity of the 
 skin, cold and clammy perspiration, hurried respiration, and 
 exceedingly quick and feeble pulse; the teeth for the most part 
 were closed, and the patient was constantly spitting through 
 the closed teeth a viscid frothy phlegm. There was also loss 
 
660 SOLANINE. 
 
 of speech; the tongue was covered with a dark brown moist 
 fur; the expression was anxious, and the patient was extremely 
 restless. Death took place on the second day. (Med.-Chir. 
 Rev., Oct., 1859, p. 389.) Dr. Christison quotes an instance 
 in which four persons were seized with , vomiting, insensibility 
 and convulsions after eating potatoes which had begun to germ- 
 inate and shrivel. 
 
 Solanine, in its pure state, seems to be much less potent in 
 its effects than most of the alkaloids heretofore considered. In 
 a series of experiments instituted by M. Schroflf, and cited by 
 Dr. Stille (Mat. Med., i, 763), with this substance, administered 
 to healthy individuals in doses varying from one-thirtieth of 
 a grain to three grains, he observed increased cutaneous sensi- 
 bility, itching of the skin, gaping, general numbness, sleepiness, 
 slight tonic cramps in the legs, and increased frequency of the 
 pulse, which at the same time grew feeble and thready; there 
 was also some dyspnoea and oppression in breathing, with nausea 
 and unsuccessful efforts to' vomit ; the head was hot, heavy, and 
 dizzy, with drowsiness, yet with inability to sleep; the extrem- 
 ities were cold, the skin dry and itching, and there was marked 
 general debility: the pupil remained unchanged. 
 
 Treatment. — The treatment in poisoning by solanine or any 
 of the plants that owe their activity to its presence, would con- 
 sist in the speedy removal of the poison from the stomach by 
 an emetic or the use of the stomach-pump. Vegetable infusions 
 containing tannic acid, and stimulants, might be found useful. 
 
 Post-mortem Appearances. — In regard to the morbid 
 changes produced by this substance, we are not acqua,inted 
 with any instance in which they have been observed, in the 
 human subject. 
 
 Chemical Properties. 
 
 In the Solid State. — Solanine, when perfectly pure, may 
 be obtained in the form of beautiful, tufts of colorless, delicate, 
 crystalline needles. As usually met with in the shops, it has 
 a more or less yellow color, and is either in the form of an 
 amorphous powder or as crystalline scales and granules. The 
 pure alkaloid is destitute of odor, and has a bitter taste, followed 
 
CHEMICAL PROPERTIES. 661 
 
 by an acrid sensation in the throat. When gradually heated 
 on porcelain, it fuses, then turns black, gives off dense white 
 fumes, and leaves a solid carbonaceous residue ; when heated in 
 a direct flame, it readily takes fire, and is quickly consumed. 
 
 Although having only a feeble alkaline reaction, solanine 
 readily combines with acids forming salts, several of which have 
 been obtained in the crystalline state. The uncrystallisable 
 salts usually appear in the form of transparent, colorless, gum- 
 like masses. The salts of solanine are odorless, and have the 
 bitter, acrid taste of the pure alkaloid. 
 
 Cold concentrated sulphuric acid, when brought in contact 
 with pure solanine, immediately causes it to assume an orange- 
 brown color, and slowly dissolves it to an orange-yellow solution; 
 if the solution be heated, its color is quickly changed to deep 
 dark-brown. Concentrated nitric acid readily dissolves the alka- 
 loid to a colorless solution, which after a time acquires a rose-red 
 tint. This color is developed in considerable intensity, if only a 
 drop of the acid be employed, from the 100th part of a grain of 
 the alkaloid ; but with the 500th of a grain, the color is only just 
 perceptible. If the nitric acid solution be heated, it acquires a 
 faint yellow color. So, also, hydrochloric acid dissolves it with- 
 out change of color; under the action of heat, the solution 
 throws down a white flocculent precipitate. 
 
 If solanine be heated for some time with diluted sulphuric 
 or hydrochloric acid, as first observed by MM. Zwenger and 
 Kind, it is resolved into grape-sugar and a new, strongly basic 
 alkaloid, which these observers named solanidine, and which, 
 especially as the mixture cools, is deposited in combination with 
 the acid employed, in the crystalline form. (Chem. Gazette, 
 1859, p. 308.) According to O. Gmelin, this decomposition 
 takes place with diluted sulphuric acid at a temperature of 
 122° F. He assigned to solanidine the formula C52H42O4. 
 
 Solubility. — When excess of finely-powdered solanine is di- 
 gested in pure water, at the ordinary temperature, with frequent 
 agitation, for several hours, one part dissolves in 1,750 parts of 
 the menstruum. The alkaloid is freely soluble in alcohol, which 
 on slow evaporation leaves it principally in the form of delicate, 
 silky, crystalline needles, Plate XIII, fig. 5. It is only very 
 
662 SOLANINE. 
 
 sparingly soluble in absolute ether, and almost wholly insoluble 
 in chloroform, requiring about 9,000 parts of the former, and 
 not less than 50,000 parts of the latter liquid for solution. 
 Amylic-alcohol, when frequently agitated with excess of the 
 powdered alkaloid, for several hours, dissolves one part in 1,060 
 parts of the liquid. 
 
 From the facts just stated, it is obvious that solanine can 
 not be extracted in very notable quantity from aqueous mix- 
 tures, either by ether or chloroform. From mixtures of this 
 kind, however, the alkaloid may be separated by hot amylic- 
 alcohol, or, better still, by a mixture of ether and alcohol, in 
 which mixture it is rather freely soluble. Thus, when ten- 
 hundredths of a grain of the alkaloid, in the form of sulphate, 
 was dissolved in thirty grains of water, and the solution, after 
 the addition of slight excess of caustic potash, agitated with 
 five volumes of a mixture of two parts of absolute ether and 
 one part of pure alcohol, this mixture extracted nine-hundredths 
 of a grain of the pure alkaloid, which on spontaneous evapora- 
 tion it left in the crystalline form. 
 
 The salts of solanine are, for the most part, readily soluble 
 in water; but they are insoluble in chloroform and in ether. 
 Either of the latter liquids, therefore, may be employed to sep- 
 arate foreign organic matter from aqueous solutions of salts of 
 the alkaloid. 
 
 Of solutions of Solanine. — In the following investigations, 
 in regard to the behavior of solutions of solanine, a sample of 
 colorless crystallised solapine prepared by E. Merck of Darm- 
 stadt, and a purified specimen of the commercial alkaloid were 
 employed, the former being dissolved in the form of sulphate, 
 and the latter as chloride. Merck's preparation was in the 
 form of delicate crystalline needles and thin transparent laminse. 
 The fractions employed in'dicate the fractional part of a grain 
 of the anhydrous alkaloid present in one grain of water ; and 
 the results, unless otherwise indicated, refer to the behavior of 
 one grain of the solution. One grain of a 100th aqueous solu- 
 tion of solanine in the form of sulphate, when allowed to evap- 
 orate spontaneously, deposits the alkaloidal salt chiefly in the 
 form of groups of delicate acicular crystals, Plate XIII, fig. 6. 
 
SULPHURIC ACID TEST. 6'63 
 
 1. The Alkalies and Alkaline Carbonates. 
 
 The caustic alkalies and their protocarbonates throw down 
 from concentrated solutions of salts of solanine a colorless, trans- 
 parent, gelatinous precipitate of the free alkaloid, which is read- 
 ily soluble in excess of the fixed caustic alkalies, but only 
 sparingly soluble in ammonia, and nearly wholly insoluble in 
 the alkaline carbonates. The precipitate is readily soluble in 
 free diluted acids. 
 
 !• ToT grain of solanine, in one grain of water, when treated 
 with a small quantity of either of the above reagents, the 
 mixture becomes converted into a nearly solid gelatinous 
 mass. 
 
 2. Too" grain, when treated with a small quantity of ammonia, 
 
 yields a very good flocculent precipitate. On account of 
 the ready solubility of solanine in caustic potash and soda, 
 it is difiicult to obtain a precipitate by either of these 
 reagents from a single drop of a 500th solution of the 
 alkaloid. 
 
 3. 1,000 grain, under the action of a trace of ammonia, the 
 
 mixture becomes very distinctly turbid, and after a time 
 yields a distinct precipitate. 
 The true nature of the precipitate produced by either of 
 these reagents, may be established by the following reaction. 
 
 2. Sulphuric Acid. 
 
 If a small quantity of solanine or of any of its colorless salts, 
 in the dry state, be treated with a few drops of cold concen- 
 trated sulphuric acid, the deposit immediately assumes an orange- 
 brown color, and slowly dissolves to a yellow or orange-yellow 
 solution, which after about an hour acquires a purplish-brown 
 color and throws down a brownish precipitate ; after several 
 hours, the solution becomes colorless and the precipitate assumes 
 a yellowish or dirty-white color. The intensity of the colors 
 thus produced and the time of their development, depend some- 
 what upon the quantity of the alkaloid present. Results similar 
 
664 SOLANINE. 
 
 to those just stated, are obtained when a drop of a somewhat 
 concentrated solution of a salt of the alkaloid is treated with 
 several drops of the acid. 
 
 These results are principally due, according to Zwenger and 
 Kind, to the solanidine produced from the solanine by the action 
 of the acid. On treating different samples of solanine with 
 concentrated sulphuric acid, we have frequently observed the 
 peculiar nauseous odor, first noticed by Wackenroder. When 
 a solution of the sulphate of solanine is evaporated to dry- 
 ness on a water-bath, the salt is left in the form of a hard, 
 transparent, vitreous mass, destitute of any distinct crystalline 
 structure. 
 
 1. YoTT grain of solanine, in the form of a salt, in the dry state, 
 
 when treated with a few drops of the concentrated acid, 
 soon dissolves, with an orange color, to a yellow solution, 
 from which a precipitate soon begins to separate ; this 
 increases in quantity, and after a time the liquid acquires 
 a deep-orange, then a bright-red, and finally a violet-pink 
 color, which slowly fades and after about ten hours en- 
 tirely disappears. 
 
 When one drop of a solution containing the 100th part 
 of a grain of the alkaloid is treated with several drops of 
 the acid, the mixture immediately assumes a yellow color, 
 and then passes through the changes just described. 
 
 2. i^ooo grain, both in the solid state and when in solution, 
 
 yields much the same results as the preceding quantity of 
 the alkaloid, only that the colors are less intense and per- 
 sistent. 
 
 3. lo.ouu grain: when the dry deposit is touched with a small 
 
 drop of the acid, it assumes a brownish color and dissolves 
 to a solution having a decided yellow tint, which after a 
 time changes to a very faint reddish hue. 
 
 4. su^uuo grain, under the conditions just stated, dissolves with 
 
 a just perceptible brownish tint, to a colorless solution. 
 The production of this series of colors, in connection with 
 the formation of the precipitate, is quite characteristic of sola- 
 nine. Even the 1,000th part of a grain of the alkaloid, as just 
 pointed out, will yield very satisfactory results. 
 
CHROMATE OF POTASH TEST. 665 
 
 3. Iodine in Iodide of Potassium. 
 
 An aqueous solution of free iodine in iodide of potassium 
 causes somewhat concentrated solutions of salts of solanine to 
 assume a deep orange-red color, and throws down an orange- 
 brown precipitate, which is unaffected by diluted acids. 
 1- Tffo" grain of solanine, in solution in one grain of water, 
 yields the results just stated. The precipitate is readily 
 soluble in caustic potash to a colorless solution, from which, 
 after a time, a dirty-white precipitate separates. 
 2. TTF^oo grain: an orange-brown solution, and a slight precipitate. 
 3- 5,0*0 grain : the mixture assumes a yellowish-brown color, 
 but fails to yield a precipitate. 
 The reactions of the first-two mentioned solutions are pecul- 
 iar to solanine ; but with more dilute solutions the results are 
 uncertain, since the reagent itself imparts a more or less yel- 
 lowish-brown color, even to pure water. It must also be borne 
 in mind that the reagent produces reddish-brown precipitates 
 with most of the other alkaloids and with certain other organic 
 substances. 
 
 4. Chromate of Potash. 
 
 Protochromate of potash produces in solutions of salts of 
 solanine, when not too dilute, a yellow amorphous precipitate, 
 which is insoluble in excess of the precipitant, but readily solu- 
 ble in acetic acid. If the mixture, containing the deposit, be 
 treated with several drops of concentrated sulphuric acid, the 
 precipitate quickly dissolves, and the solution slowly acquires a 
 bluish or bluish-green color, which remains unchanged for sev- 
 eral hours. The production of this color is peculiar to the pre- 
 cipitate produced from solutions of solanine. 
 
 1. xwo grain of solanine, in one grain of water, yields a very 
 
 copious precipitate, which, when treated with sulphuric 
 acid, undergoes the changes just described. 
 
 2. Tr5^"o grain: the mixture immediately becomes turbid, and 
 
 after a little time yields a quite fair, yellow, flocculent 
 precipitate. If the precipitate be dissolved in a few drops 
 
 43 
 
666 SOLANINE. 
 
 of sulphuric acid, the solution soon acquires a quite dis- 
 tinct bluish-green color. 
 
 3. s.Joo grain: after a time, a slight deposit of yellowish flakes. 
 Bichromate of potash produces much the same reactions as 
 
 the protochromate, but the precipitate does not appear in quite 
 as dilute solutions, since it is somewhat soluble in the chromic 
 acid eliminated by the reaction, when this reagent is employed. 
 
 5. Bromine in Bromohydrie Acid. 
 
 An aqueous solution of bromohydrie acid saturated with free 
 bromine throws down from solutions of salts of the alkaloid an 
 orange-yellow or yellow amorphous precipitate, which is spar- 
 ingly soluble in diluted acetic acid. After a time, the precip- 
 itate acquires a dirty-white color, and slowly disappears. 
 1. j-^o- grain of solanine, in one grain of water, yields a very 
 copious orange-yellow precipitate. 
 
 4. 1,0 grain : a quite good, yellow deposit. 
 
 3. 5,Joo grain, yields only a just perceptible turbidity. 
 
 The reaction of this reagent is common to solutions of vari- 
 ous other organic substances, besides solanine. 
 
 Other Reagents. — Carha^otic acid produces in concentrated 
 solutions of salts of solanine, a copious, yellow, gelatinous pre- 
 cipitate, which is readily soluble in excess of the precipitant. 
 Tannic acid occasions a white, flocculent precipitate. Oxalate 
 of ammonia, and phosphate of soda produce, in similar solutions, 
 white, gelatinous precipitates. 
 
 Neither of the following reagents produce a precipitate, even 
 in concentrated solutions of salts of the alkaloid : sulphocyanide 
 of potassium, ferro- nor ferri-cyanide of potassium, the chlorides 
 of gold, platinum, and palladium, iodide of potassium, sesqui- 
 chloride of iron, nor free chromic acid. 
 
 Separation from Organic Mixtures. 
 
 Although there is no difficulty in identifying even a minute 
 trace of solanine when in its pure state, yet when present only 
 
SEPARATION FROM ORGANIC MIXTURES. 667 
 
 in minute quantity in complex organic mixtures, its separation 
 in a state sufficiently pure for testing is attended with consid- 
 erable difficulty, and is sometimes impossible, at least by any 
 method with which we are acquainted. As the alkaloid is nearly 
 wholly insoluble both in ether and chloroform, it is obvious, as 
 heretofore stated, that neither of these liquids wiU serve to sep- 
 arate it from organic mixtures. 
 
 The suspected mixture, as the contents of the stomach, 
 after being carefully examined for the presence of any solid 
 portions of the poisonous plant, is very slightly acidulated with 
 a drop or two of sulphuric acid, and gently heated with half 
 its volume of alcohol, for about half an hour. The mass is 
 then allowed to cool, transferred to a linen strainer, and the 
 strained liquid concentrated on a water-bath to a small volume, 
 after which it is filtered. The filtrate is evaporated, at a tem- 
 perature not exceeding 120° F., to almost dryness, the residue 
 well stirred with a small quantity of pure water, and the solu- 
 tion filtered. Any solanine present will now exist in the filtrate 
 in the form of sulphate, and may, if not in too minute quantity, 
 be separated by either of the following methods, the first of 
 which is based upon the principles first applied by Wackenroder 
 for the preparation of the alkaloid, and the second upon those 
 first announced by Uslar and Erdmann. 
 
 According to the first of these methods, the clear filtrate is 
 treated with slight excess of powdered hydrate of lime, and 
 the mixture allowed to repose in a cool place for from twelve 
 to twenty-four hours, in order that the eliminated solanine may 
 completely subside. The precipitate is then collected on a 
 filter, and allowed to drain, then washed with a small quantity 
 of cold water containing a trace of carbonate of ammonia, and, 
 while still moist, gently warmed with about half an ounce of 
 strong alcohol, which wiU dissolve the alkaloid, whilst the sul- 
 phate of lime and any excess of caustic lime employed will 
 remain, being insoluble in this liquid. The alcoholic solution, 
 after filtration, is gently evaporated to dryness, the residue 
 treated with a small quantity of water very slightly acidulated 
 with acetic acid, and the solution filtered. A drop of the filtrate 
 may now be treated with several drops of cold concentrated 
 
668 SOLANINE. 
 
 sulphuric acid, and if, after a time, it yields satisfactory evi- 
 dence of the presence of solanine, other portions of the solution 
 may be examined by some of the other tests for the alkaloid. 
 Should, however, the sulphuric acid test fail, the filtrate is 
 concentrated and another drop examined in the same manner, 
 before applying any of the other tests. 
 
 Or, secondly, the filtrate, supposed to contain the sulphate 
 of solanine, may be agitated with an equal volume of warm 
 amylic-alcohol, which, after the liquids have completely sepa- 
 rated, is decanted, and the operation repeated with a fresh 
 portion of the alcohol. By this treatment, much of the coloring 
 matter will be removed, while the alkaloidal salt will remain in 
 the aqueous solution. This solution is then treated with slight 
 excess of carbonate of ammonia, and agitated with hot amylic- 
 alcohol, which will now dissolve the liberated alkaloid. The 
 alcoholic solution is decanted, the aqueous liquid washed with a 
 fresh portion of the hot alcohol, and the mixed alcohols evap- 
 orated to dryness on a water-bath. The residue is stirred with 
 strong, ordinary alcohol, the solution filtered and evaporated to 
 dryness. The residue thus obtained is treated with a small 
 quantity of water containing a trace of acetic acid, and the 
 filtered solution examined in the manner described in the pre- 
 ceding paragraph. 
 
 On following the methods now considered, for the examina- 
 tion of complex organic mixtures containing two drachms of 
 Thayer's Fluid extract of Dulcamara — the medicinal dose of 
 which is from half a drachm to one drachm — we recovered by 
 each a very notable quantity of solanine, in its very nearly 
 pure state, especially when precipitated from the final aqueous 
 solution by an alkali. The first-mentioned method furnished 
 somewhat the best results; however, the quantity of the alka- 
 loid recovered by either process was several times more than 
 sufficient to fully establish the presence of the poison. 
 
PLATE I. 
 
Pig. 1. j^ grain Potash, in the form of nitrate or chloride, + Bichloride of 
 Platinum, X 225 diameters. 
 
 " 2. Yhs grain Potash, as nitrate, + Tartaric Acid, X 100 diameters. 
 
 " 3. j^ grain Potash, as chloride, + TaHrate of Soda, X 80 diameters. 
 
 " 4. -^ grain Potash, as nitrate, + Carbazotic Acid, X 40 diameters. 
 
 " 5- lis grain Ammonia, as chloride, + Carbazotic Acid, X 40 diameters. 
 
 " 6. y5 grain Soda, + Carbazotic Acid, X 40 diameters. 
 
I-'l,Ll(-l 
 
 //>/ / 
 
 J'". 
 
 F„r 
 
 J-'/Kf O 
 
PLATE 11. 
 
Pig. 1. 5V — Tiff grain Soda, + Antimoniate of Potash, X 100 diameters. 
 " 2. -jij grain Soda, + Tartaric Acid, X 40 diameters. 
 " 3. YffVr grain Soda, as chloride, + Bichloride of Platinum, X 40 diameters. 
 " 4. Yvn grain StTLPHURic Acid, + Chloride of Barium, X 100 diameters. 
 " 5. Htdrofluosilicic Acid, + Chloride of Barium, X 100 diameters. 
 " 6. xhi grain Sulphuric Acid, + Nitrate of Strontia, X 75 diameters. 
 
I'l.lh 
 
 /■;,/ / 
 
 /;■,/ 
 
 })V. 
 
 /■;,,.-!,. 
 
 /"/ 
 
 /■),,o 
 
PLATE IIL 
 
Pig. 1. XTO grain Hydrochloric Acid, + Acetate of Lead, X 40 diameters. 
 
 " 2. xAt grain Oxalic Acid, on spontaneous evaporation, X 80 diameters. 
 
 " 3. xiAnr grain Oxalic Acid, + Ohloride of Calcium, X 225 diameters. 
 " 4. j^ grain Oxalic Acid, + Chloride of Barium, X 80 diameters. 
 " 5- Tfftr grain Oxalic Acid, + Nitrate of Strontia, X 125 diameters. 
 " 6. y^TT grain Oxalic Acid, + Acetate of Lead, X 80 diameters. 
 
I III,,' III 
 
 //// ■ ■> 
 
 /■',, 
 
PLATE IT. 
 
Fig. 1. Tsi^T! grain Hydrocyanic Acid vapor, + Nitrate of Silver, X 225 
 diameters. 
 
 " 2. xwffinr grain Hydrocyanic Acid vapor, + Nitrate of Silver, X 125 
 diameters. 
 
 " 3. ^Vii grain Phosphoric Acid, + Ammonio- Sulphate of Magnesia, 
 X 80 diameters. 
 
 " 4. Tartar Emetic, from hot supersaturated solution, X 40 diameters. 
 
 " 5. Arsenious Acid, sublimed, X 125 diameters. 
 
 " 6. XS7 grain Arsenious Acid, + Ammonio- Nitrate of Silver, X T5 di- 
 ameters. 
 
PLllrl\- 
 
PLATE V. 
 
Fig. 1. yjj- grain Arsenic Acid, + Ammonio-Sulphaie of Magnesia, X T5 
 diameters. 
 
 '' 2. Corrosive Sublimate, sublimed, X 40 diameters. 
 
 " 3. t-Jtj- grain Lead, + diluted Sulphuric Acid, X 80 diameters. 
 " 4. xrzr grain Lead, + diluted Hydrochloric Acid, X 80 diameters. 
 
 " 5. yjVTT grain Lead, + Iodide of Potassium, X 80 diameters. 
 
 " 6. xwiT grain Zinc, + Oxalic Acid, X 80 diameters. 
 
I'lii.'V 
 
 7/// / 
 
 /vv ..^ 
 
 /■'", 
 
 />,/ ; 
 
PLATE YI. 
 
^IG 
 
 . 1. 
 
 
 2. 
 
 
 3. 
 
 
 4. 
 
 
 5. 
 
 
 6. 
 
 xffT grain Nicotine, + Bichloride of Platinum^ X 40 diameters. 
 
 X5Ty grain Nicotine, + Corrosioe Sublimate, X 40 diameters. 
 nrVir grain Nicotine, + Oarbazotic Add, X 40 diameters. 
 CoNiifE, pure, + vapor of MydrocMorie Acid, X 40 diameters. 
 
 x^^ grain Conine, + Oarbazotic Add, X 40 diameters. 
 
 T^u grain Morphine, + Potash or Ammonia, X 40 diameters. 
 
'L'ikAI 
 
 //// / 
 
 /;,/...-'' 
 
 ////.. v. 
 
 ri„-'r 
 
 J-'/J/./'. 
 
PLATE YII. 
 
-lal.Al 
 
 /;,/, 
 
 /■■„r-:'- 
 
 n„ 
 
 ri„.j-r. 
 
 '-„,.. 
 
 FI,,.fK 
 
PLATE YIII. 
 
Fia. 
 
 1. 
 
 (( 
 
 2. 
 
 C( 
 
 3. 
 
 (1 
 
 4. 
 
 a 
 
 5. 
 
 (( 
 
 6. 
 
 ^ grain Mecoitic Acid, + Chloride of Calcium^ X '?5 diameters. 
 TtjVff grain Narcotine, + Potash or Ammonia, X 40 diameters. 
 T^ grain Naecotine, + Acetate of Potash, X 80 diameters. 
 xhv grain Codeine, + Iodine in Iodide of Potassium, X 40 diameters. 
 Xffxr grain Iodide of Codeine, from alcoliolic solution, X 75 diameters. 
 Yhs grain Codeine, + Sulphocyanide of Potassium, X 40 diameters. 
 
,ll(' 
 
 /;./ / 
 
 J'),, V 
 
 /■-M-'r 
 
 /'■>,,-' 
 
 Fill o. 
 
PLATE IX. 
 
Fig. 1. xJj grain Codeine, + Bichromate of Potash, X 40 diameters. 
 
 " 2. j^ grain Codeine, + Iodide of Potassium, X 40 diameters. 
 
 " 3. TiArTr grain Narceine, + Iodine in Iodide of Potassium, X 40 diameters. 
 
 " 4. ^ grain Narceine, + Bichromate of Potash, X 40 diameters. 
 
 " 5- shi grain Opianyl, + Iodine in Iodide of Potassium, X 40 diameters. 
 
 " 6. ^-a grain Opianyl, + Bromine in Bromohydric Add, X 40 diameters. 
 
l-'],iirlX 
 
 f,;,. /. 
 
 /; 
 
 "/-■ 
 
 /■/„.:, 
 
 //If '/-. 
 
 'vy. . > 
 
 I'll/ o 
 
PLATE X. 
 
Fig. 
 
 1. 
 
 (( 
 
 2. 
 
 it 
 
 3. 
 
 u 
 
 4. 
 
 u 
 
 5. 
 
 xhs grain Strychnine, + Potash or Ammonia, X 40 diameters. 
 TW grain Strychnine, + SulpJiocyanide of Potassium, X 40 diameters, 
 •j^ grain Strychnine, + Bichromate of Potash, X 40 diameters. 
 Tstns grain Strychnine, + Bichromate of Potash, X 80 diameters. 
 Y^jrs grain Strychnine, + Chloride of Gold, X 40 diameters. 
 6. xxnnr grain Strychnine, + Bichloride of Platinum, X 40 diameters. 
 
11,-ii.> x 
 
 /;;/y. 
 
 /;>, 
 
 /;>/.,- 
 
 Fiif.J-r. 
 
 /'/If ■ > 
 
 />//,/', 
 
PLATE XI. 
 
Fig. 1. ^^^ grain Strychnine, + Oarbazotic Acid, X 80 diameters. 
 
 " 2. ^hs grain Strychnine, + Corrosive Sublimate, X 40 diameters. 
 
 " 3. x^j- grain Strychnine, + Ferricyanide of Potassium, X 40 diameters. 
 
 " 4. xTRTiT grain Strychnine, + Iodine in Iodide of Potassium, X 80 di- 
 ameters. 
 
 " 5. xsTT grain Bruoine, + Potash or Ammonia, X 40 diameters. 
 
 " 6, xitr grain Brucine, + SulpTiocyanide of Potassium, X 40 diameters. 
 
ihu-Jl. 
 
 //./.?. 
 
 /;>/,.'. 
 
PLATE XII. 
 
Pig. 
 
 1. 
 
 K 
 
 2. 
 
 U 
 
 3. 
 
 U 
 
 4. 
 
 " 
 
 5. 
 
 Y^ grain Brucine, + Bichromate of Potash, X 80 diameters. 
 XTTinr grain Brucike, + Bichloride of Platinum, X 40 diameters. 
 Y^ grain Bbucine, + Ferricyanide of Potassium, X 40 diameters. 
 TOT grain Atropine, + Potash or Ammonia, X 75 diameters. 
 Twn grain Atropine, + Bromine in Bromohydric Acid, 'x f 5 di- 
 ameters. 
 6. TtrJtnr grain Atropinb, + Bromine in Bromohydric Acid, X 125 di- 
 ameters. 
 
Clii.-XII 
 
 /;-./ / 
 
 j//f.^/ 
 
 l^li/.-r. 
 
PLATE XIII. 
 
Pi6. 1. xJt grain Atropine, + Carhazotic Acid, X 80 diameters. 
 
 " 2. -fffTf grain Atropine, + Ohhride of Gold, X 80 diameters. 
 
 " 3- lis grain Veratrine, + Chloride of Gold, X 40 diameters. 
 
 " 4. x¥ir grain Veratrine, + Bromine in Bromohydric Acid, X 80 diameters. 
 
 " 5. SoLANiNE, from alcoholic solution, X 80 diameters. 
 
 " 6. xJtt grain Solaninb, as sulphate, on spontaneous evaporation, X 80 
 diameters. 
 
'laic 
 
 //// / 
 
 /;v 
 
 /; 
 
 I If-' 
 
 //,/-'/- 
 
 / 'ill. o. 
 
INDEX 
 
 FAQE, 
 
 Absorption, effects of, 57 
 
 Acetate of lead, fatal quantity, . . 357 
 General chemical nature, . . . 358 
 
 Period when fatal, 356 
 
 Poisoning by, 355 
 
 Post-mortem appearances, . . . 357 
 Quantitative analysis, .... 372 
 Recovery from organic mixtures, 369 
 
 Solubility, 358 
 
 Special chemical properties, 359-369 
 Symptoms produced by, ... 355 
 Treatment of poisoning by, . . 357 
 
 Acid, arsenic, 310 
 
 Arsenious, 240 
 
 Comenic, 485 
 
 Hydrochloric, poisoning by, . . 138 
 Hydrocyanic, poisoning by, . . 167 
 
 Igasuric, 529 
 
 Meconic, 483 
 
 Nitric, poisoning by, 120 
 
 Oxalic, poisoning by, .... 150 
 
 Phosphoric 206 
 
 Pyromeconic, 485 
 
 Strychnic, 529 
 
 Sulphuric, poisoning by, ... 98 
 Acids, mineral, nature and effects of, 97 
 Aconite, fatal quantity, .... 610 
 
 Period when fatal, 610 
 
 Poisoning by, 608 
 
 Post-mortem appearances, . . . 613 
 Symptoms produced by, . . . 608 
 Treatment of poisoning by, . . 612 
 Aconitine, chemical properties of, . 614 
 Fallacies of tests for, . . . .618 
 
 History 606 
 
 Physiological test for, . . . .619 
 
 Poisoning by, 612 
 
 Preparation, 606 
 
 Aconitine, recovery from the blood, 620 
 
 Solubility, 616 
 
 Separation from organic mixtures, 619 
 
 Aconitum napellus, 606 
 
 Alkalies, distinguishing properties, 71 
 
 Fatal quantity, 68 
 
 General chemical nature of, . . 65 
 Pathological effects of, ...''. 69 
 
 Period when fatal, 67 
 
 Symptoms produced by, . . . 66 
 Treatment of poisoning by, . . 69 
 
 Vegetable, 409 
 
 Alkaloids, fixed, general nature of, . 409 
 Graham and Hofmann's method 
 
 for recovering, 419 
 
 Liquid, 409 
 
 Recovery by Dialysis, .... 420 
 By method of Stas, . . . .411 
 Alkaloids, Rodgers and Girdwood's 
 
 method, 416 
 
 TTslar and Erdmann's method, . 417 
 
 Ammonia, carbonate of, .... 67 
 
 Density of solutions of, . ... 88 
 
 Effects of vapor, 67 
 
 General chemical nature, ... 88 
 
 Period when fatal, 68 
 
 Quantitative analysis, .... 96 
 
 Separation from organic mixtures, 95 
 
 Special chemical properties, . 89-95 
 
 Symptoms produced by, ... 66 
 
 Analyses, precautions in regard to, 50 
 
 Analysis, substances requiring, . 49 
 
 Analyst, qualifications requisite, . 60 
 
 Aniline, source of fallacy, .... 560 
 
 Antimonuretted hydrogen, . . . 227 
 
 Antimony, history of, 216 
 
 Recovery from the tissues, . . . 236 
 Separation from complex mixtures, 233 
 
696 
 
 ANT— BRU 
 
 ^ PAOE. 
 
 Antimony, quantitative analysis, . 237 
 
 Apparatus, chemical, 60 
 
 Appearances, post-mprtem, ... 46 
 Aqua ammonia, chemical proper- 
 ties of, 88 
 
 Poisoning by 66 
 
 Aqua fortis, 120 
 
 Arsenic acid, general chemical na- 
 ture 310 
 
 Physiological effects of, . . . .311 
 Quantitative analysis, .... 317 
 
 Eeinsch's test for, 315 
 
 Special chemical properties, 311-317 
 Sulphuretted hydrogen test, . . 312 
 
 Arsenic, compounds of, 240 
 
 Eating of, 36 
 
 . Metallic, history, 238 
 
 Physiological effects, .... 239 
 Special chemical properties, . 239 
 
 White, 240 
 
 Arsenious acid, 240 
 
 Antidotes for, 246 
 
 Antiseptic properties of, . ,. . 248 
 Chromate of potash test, . . . 295 
 Danger and Flandin's method, . 305 
 Detection after long periods, . . 308 
 Detection in the stomach, . . . 297 
 In vomited matters, .... 297 
 Distinguished from arsenic acid, 295 
 Duflos and Hirsch's method, . . 306 
 External application of, ... 243 
 
 Failure to detect, 307 
 
 Fallacies of Reinsch's test, . . 273 
 
 Of sulphur test, 267 
 
 Fatal quantity, 244 
 
 Fresenius and Baho's method, . 300 
 General chemical nature, . . . 250 
 Iodide of potassium test, . . . 295 
 
 Lime-water test, 294 
 
 Marsh's test, 278 
 
 Bloxam's modification, . . . 292 
 Delicacy of, . . . 282, 286, 290 
 Fallacies of, . . . 284, 287, 291 
 . 259 
 . 258 
 , 244 
 248 
 309 
 307 
 
 Nitrate of silver test, 
 Of solutions of, ... 
 Period when fatal, . . 
 Post-mortem appearances, 
 Quantitative analysis, . 
 Recovery from the urine, 
 
 FAGE. 
 
 Arsenious acid, reduction test, , . 255 
 
 Reinsch's test, 269 
 
 Interferences of, 276 
 
 Separation from organic mixtures, 296 
 
 From the tissues, 299 
 
 Solubility in water, 250 
 
 In alcohol, 253 
 
 In chloroform, 253 
 
 Sublimation test for, 254 
 
 Sulphate of copper test,' . . . 261 
 Sulphuretted hydrogen test, . . 263 
 Symptoms produced by, . . . 241 
 
 Taste of, 241 
 
 Time of symptoms, 242 
 
 Treatment for, 245 
 
 Vaporisation of, 253 
 
 Varieties of, 241 
 
 Asagrffia ofScinalis, 643 
 
 Atropa belladonna, 621 
 
 Atropia 621 
 
 Atropine, chemical properties of, . 628 
 External application of, ... 627 
 
 History, 621 
 
 Physiological test, 633 
 
 Poisoning by, 626 
 
 Postmortem appearances, . . . 628 
 
 Preparation, 622 
 
 Recovery from the blood, . . . 636 
 Separation from complex mix- 
 tures, 634 
 
 Solubility, 629 
 
 Subcutaneous injection of, . . .627 
 Treatment for poisoning by, . . 628 
 
 Bbiladonna, poisoning by, . . . 623 
 
 Post-mortem appearances, . . . 628 
 
 Symptoms produced by, .... 623 
 
 Treatment of poisoning by, . . 628 
 
 Binoxalate of potash, poisoning by, 71 
 
 Bittersweet, 658 
 
 Blue vitriol, 374 
 
 Bloxam's method for detecting ar- 
 senic, 292 
 
 Brucia, 593 
 
 Brucine, general chemical nature, . 594 
 
 History, 593 
 
 Nitric acid and tin test, .... 597 
 
 Physiological effects, 594 
 
 Preparation, 594 
 
BRU— DUF 
 
 697 
 
 PAGE. 
 
 Brucine, recovery from the blood, . 605 
 
 From the stomach, 605 
 
 Separation from organic mixtures, 604 
 
 Solubility 595 
 
 Special chemical properties, . . 595 
 Sulphuric acid and nitre test, . 598 
 Test for nitric acid, 131 
 
 Burnett's disinfecting fluid, . . . 394 
 
 C^siA, 65 
 
 Causes modifying effects of poisons, 35 
 Chemical analysis, importance of, . 48 
 
 Failure of, 56 
 
 Decomposition of poisons, ... 58 
 
 Reagents, 59 
 
 Tests, value of, 52 
 
 Chloride of zinc, poisoning by, . . 895 
 Classification of poisons, .... 37 
 
 Codeia, 513 
 
 Codeine, general chemical nature, . 514 
 
 History, 513 
 
 Preparation, 514 
 
 Physiological effects, 514 
 
 Salts of, 516 
 
 Solubility, 515 
 
 Tests for, 516-520 
 
 Comenic acid, 485 
 
 Compound poisoning, 40 
 
 Conia, 443 
 
 Conicine, 443 
 
 Conine, distinguished from nicotine, 455 
 Fallacies of tests for, .... 454 
 General chemical nature, . . . 447 
 
 History, 443 
 
 Physiological effects of, ... . 445 
 
 Preparation, 444 
 
 Solubility, 448 
 
 Special chemical properties, 448-454 
 Recovery from the blood, . . . 456 
 
 Salts of, 450 
 
 Separation from organic mixtures, 455 
 
 Conium maculatum, 443 
 
 Copper, chemical properties of 
 
 salts of, 378 
 
 Combinations, 374 
 
 Fatal quantity, 377 
 
 History and chemical nature, . . 373 
 
 Of solutions of, 379 
 
 Period when fatal, . . . . 376 
 
 PAGE, 
 
 Copper, physiological effects, . . . 375 
 Post-mortem appearances, . . . 378 
 Quantitative analysis, .... 391 
 Recovery from organic mixtures, 388 
 
 From the tissues, 390 
 
 From the urine, 391 
 
 Sulphate, 374 
 
 Special chemical properties, 379-388 
 
 Subacetate, 374 
 
 Symptoms produced by, . . . 375 
 Treatment of poisoning by, . . 377 
 
 Corrosive sublimate, chemical prop- 
 erties, 328 
 
 Chloride of tin test for, . . 329, 336 
 Chronic poisoning by, . . . 322 
 
 Composition, 320 
 
 Copper test for, 337 
 
 External application 323 
 
 Failure to detect, 351 
 
 Fatal quantity, . .... 324 
 General chemical nature, . . . 327 
 
 Period when fatal, 323 
 
 Poisoning by, 320 
 
 Post-mortem appearances, . . . 325 
 Quantitative analysis, .... 352 
 Recovery from organic mixtures, 344 
 
 From the urine, 351 
 
 Reduction test, 330 
 
 Solubility, 327 
 
 Sulphuretted hydrogen test, . . 334 
 Symptoms produced by, . . . 320 
 Treatment of poisoning by, . . 324 
 
 Curara, properties of, 561 
 
 Curarine, 561 
 
 Danger and Flandin's method for . 
 
 detecting arsenic, 305 
 
 Datura stramonium, 636 
 
 Daturia, 636 
 
 Daturine, chemical properties, . . 640 
 
 History, 636 
 
 Preparation, . . ... 637 
 Recovery from the blood, . . . 642 
 Separation from organic mixtures, 641 
 Dialysis, method of application, . 420 
 Disease, modifying influence of, . . 37 
 Diseases simulating poisoning, . . 43 
 Duflos and Hirsch's method for de- 
 tecting arsenic, 306 
 
698 
 
 ELI— MER 
 
 PA81:. 
 
 Elimination of poisons 58 
 
 Evidences of poisoning, .... 39 
 
 Evidence from chemical analysis, . 48 
 
 From post-mortem appearances, . 44 
 
 Failure to detect poison, .... 56 
 Fresenius and Babo's method of 
 
 analysis, 300 
 
 Galvanised iron, poisoning hy, . . 396 
 Graham and Hofmann's method for 
 recovering strychnine, .... 419 
 
 Habit, modifying influence of, . . 36 
 
 Hellebore, American, poisoning by, 646 
 
 White, poisoning by, 645 
 
 Post-mortem appearances, . . 648 
 
 Symptoms, 645 
 
 Treatment, 648 
 
 Hemlock, detection in organic mix- 
 tures, 455 
 
 Poisoning by, 444 
 
 Post-mortem appearances, . . . 446 
 Symptoms produced by, . . . 444 
 Treatment of poisoning by, . . 446 
 
 Hydrochloric acid, density of solu- 
 tions of, 142 
 
 Fatal quantity, ... ... 140 
 
 General chemical nature, . . . 141 
 
 Period when fatal, 189 
 
 Poisoning by, .138 
 
 PosUmortem appearances, . . . 141 
 Quantitative analysis, . . . 149 
 Recovery from organic mixtures, 146 
 From organic fabrics, .... 148 
 Special chemical properties, 143-146 
 Symptoms produced by, . . 139 
 
 Test for meconic acid, .... 490 
 Treatment of poisoning by, . . 141 
 
 Hydrocyanic acid, failure to detect, 191 
 
 Fatal quantity, 172 
 
 General chemical nature, . . . 175 
 History and composition, . . . 167 
 
 Period when fatal, 171 
 
 Poisoning by, 167 
 
 Post-mortem appearances, . . . 174 
 Quantitative analysis, .... 192 
 Becovery from the blood, . . . 190 
 Separation from organic mixtures, 187 
 
 Hydrocyanic acid, special chemical 
 
 properties, 176-187 
 
 Symptoms produced by, . . . 169 
 Treatment of poisoning by, . .178 
 
 Hydrofluosilicic acid, as a reagent, 80 
 
 Idiostnckasy, effects of, .... 35 
 
 Igasuric acid, 629 
 
 Indian poke, 646 
 
 Intestines, perforation of, .... 47 
 Irritant poisons, effects of, . . 37, 45 
 Irritant poisoning, morbid appear- 
 ances in, 45 
 
 Jamestown weed, poisoning by, . 637 
 
 Laudanum, 457 
 
 Lead, acetate, fatal quantity, . . 357 
 Acetate, general chemical nature, 858 
 
 Period when fatal, 356 
 
 Post-mortem appearances, . . 357 
 
 Solubility, 358 
 
 Special chemical properties, 359-369 
 Symptoms produced by, . . . 355 
 Treatment of poisoning by, . . 357 
 Detection in the urine, .... 872 
 External application of, . . 356 
 History and chemical nature, . . 854 
 Physiological effects of, ... . 855 
 Quantitative analysis, .... 372 
 Separation from organic mixtures, 369 
 
 From the tissues, 871 
 
 Sulphuretted hydrogen test for, . 361 
 Lithia, chemical properties of, . . 65 
 
 Maksh's test for arsenic, . . . • . 278 
 
 Meconic acid, failure to detect, . . 503 
 
 General chemical nature, . . . 484 
 
 History 483 
 
 Iron test for, 486 
 
 Physiological effects of, ... . 484 
 
 Preparation, 483 
 
 Recovery from the blood, . . . 500 
 
 From the tissues, 500 
 
 Separation from organic mixtures, 492 
 Solubility, ........ 484 
 
 Special chemical properties, 485-492 
 
 Meconine, 524 
 
 Mercury, compounds of, .... 819 
 
MER— OPI 
 
 699 
 
 PAGE. 
 
 Mercury, detection in the urine, . 351 
 Metallic, properties of, ... . 319 
 Physiological effects, .... 319 
 
 Protochlorlde of, 320 
 
 Micro-chemistry of poisons, definition, 33 
 Microscope, application of, ... 34 
 Mineral acids, nature and effects of, 97 
 
 Monkshood, 606 
 
 Morphia, , . . 466 
 
 Morphine, external application of, 469 
 
 Failure to detect, 503 
 
 Fatal quantity, . .... 468 
 
 General chemical nature, . . . 470 
 History and preparation, . . .466 
 Nitric acid test for, ... . 475 
 Period when fatal, ... . 468 
 Post-mortem appearances, . . . 470 
 Quantitatiye analysis, .... 504 
 RecoTery from the blood, . . . 500 
 From organic mixtures, . . . 499 
 
 From the tissues, "500 
 
 From the urine, . . . . 503 
 
 Separation from organic mixtures, 492 
 
 Solubility, 471 
 
 Special chemical properties, 473-483 
 
 Symptoms produced by, . . .467 
 
 Treatment of poisoning by, 470 
 
 Muriatic acid, .138 
 
 Napbluna, 606 
 
 Narceine, chemical tests for, 522-524 
 
 General chemical nature, . . . 521 
 
 History, . 520 
 
 Physiological effects, 521 
 
 Preparation, 520 
 
 Solubility, 522 
 
 Narcotic poisons, symptoms of, . . 38 
 
 Narcotic poisoning, morbid effects of, 45 
 Narcotico-irritant poisoning, . . 38, 45 
 
 Narcotine, general chemical nature, 505 
 
 History, 504 
 
 Physiological effects of, ... . 505 
 
 Preparation, 505 
 
 Solubility, 506 
 
 Special chemical properties, 506-513 
 
 Test for nitric acid, 132 
 
 Nesler's test for ammonia, .... 92 
 
 Nicotia, 423 
 
 Nicotiana tabacum, 423 
 
 Nicotine, general chemical nature, 
 
 History, 
 
 Period when fatal, . . 
 
 Post-mortem appearances. 
 
 Preparation, .... 
 
 Recovery from the blood, 
 From organic mixtures. 
 From the tissues, . . 
 
 Salts of, 
 
 Solubility, . . . . 
 
 Special chemical properties, 
 
 Symptoms produced by, 
 
 Treatment of poisoning by. 
 Nightshade, deadly, ... 
 
 Garden, symptoms of. 
 
 Woody, 
 
 Nitrate of potash, poisoning by, 
 Nitric acid, anhydrous. 
 
 Antidotes for, . . . 
 
 Density of solutions of, 
 
 Fatal quantity, . . . 
 
 Fumes of fatal, . . , 
 
 General chemical nature. 
 
 Pathological effects, . 
 
 Period when fatal, 
 
 Poisoning by, . . . 
 
 Quantitative analysis, 
 
 Recovery from organic mix 
 From organic fabrics. 
 
 Special chemical properties. 
 
 Symptoms produced by, 
 Nux vomica, chemical propert; 
 
 Fatal quantity, .... 
 
 History and composition, 
 
 Period when fatal, . . 
 
 Physical properties, . . 
 
 Post-mortem appearances. 
 
 Symptoms produced by, . 
 
 Treatment of poisoning by. 
 
 PAGE. 
 
 . 428 
 
 . 423 
 
 . 426 
 
 . 427 
 
 . 423 
 
 , 440 
 
 . 437 
 
 , 440 
 
 . 430 
 
 . 428 
 
 429-437 
 
 424 
 
 427 
 
 621 
 
 659 
 
 657 
 
 70 
 
 124 
 
 122 
 
 125 
 
 122 
 
 121 
 
 124 
 
 122 
 
 122 
 
 120 
 
 137 
 
 134 
 
 137 
 
 125-134 
 
 120 
 
 583 
 
 532 
 
 529 
 
 531 
 
 533 
 
 532 
 
 529 
 
 532 
 
 OSsopHAGUS, perforation of. 
 Oil of vitriol, poisoning by, 
 Opianyl, chemical tests for, 
 
 General chemical nature. 
 
 History, 
 
 Physiological effects of, . 
 
 Preparation, .... 
 
 Solubility, 
 
 Opium, effects of enema of, 
 
 tures. 
 
 529, 
 
 . 47 
 . 98 
 525-528 
 . 525 
 . 524 
 . 525 
 . 524 
 . 525 
 . 460 
 
700 
 
 OPI— SOL 
 
 PAGE. 
 
 Opium, external application, . . . 459 
 
 Failure to detect, 503 
 
 Fatal quantity, 461 
 
 History and chemical nature, . . 457 
 
 Period when fatal, 460 
 
 Physical and chemical properties, 465 
 Posfc-mortem appearances, . . . 465 
 Recovery after large doses of, . 462 
 From organic mixtures, . . . 492 
 Symptoms produced by, ... 458 
 
 Time of symptoms, 459 
 
 Treatment of poisoning by, . . 463 
 
 Orpiment, 240, 263 
 
 Oxalic acid, fatal quantity, . . . 152 
 General chemical nature, . . .155 
 
 History, 150 
 
 Period when fatal, 152 
 
 Poisoning by, 150 
 
 Post-mortem appearances, . . . 154 
 Quantitative analysis, .... 167 
 Recovery from organic mixtures, 163 
 
 From the urine, 166 
 
 Solubility, 155 
 
 Special chemical properties, 156-163 
 Symptoms produced by, ... 150 
 Treatment of poisoning by, . . 153 
 
 Papavek somniferum, 457 
 
 Phosphoric acid, general chemical 
 
 nature, 206 
 
 Special chemical properties, 206-210 
 Phosphorus, failure to detect, . . 214 
 
 Fatal quantity, 194 
 
 General chemical nature, . . . 197 
 
 History, 192 
 
 Hydrogen test, 203, 213 
 
 Lipowitz test, .... 205, 212 
 Mitscherlich's test, . . . 200, 211 
 
 Period when fatal, 193 
 
 Poisoning by, 192 
 
 Post-mortem appearances, . . . 196 
 Quantitative analysis, . . . 214 
 
 Recovery as oxide, 213 
 
 From organic mixtures, . . .210 
 
 Solubility, 197 
 
 Special chemical properties, 198-206 
 Symptoms produced by, . . . 192 
 Treatment of poisoning by, . .195 
 Varieties of, 198 
 
 PAGE. 
 
 Poison, definition of, 34 
 
 Failure to detect, 49 
 
 Poisons, classification of, .... 37 
 
 Polarised light, test for soda, ... 85 
 
 Porphyroxin, 498 
 
 Post-mortem appearances, as evi- 
 dence of poisoning, 44 
 
 Postr-mortem examinations, ... 47 
 
 Potash, binoxalate, poisoning by, . 71 
 
 Carbazotic acid test for, ... 79 
 
 Density of solutions of, .... 73 
 
 Fatal quantity, 68 
 
 General chemical nature, ... 72 
 
 Nitrate of, 70 
 
 Period when fatal, 67 
 
 Platinum test for, 74 
 
 Post-mortem appearances, ... 69 
 
 Quantitative analysis, .... 82 
 
 Recovery from organic mixtures, 81 
 Special chemical properties, . 73-81 
 
 Sulphate, poisoning by, .... 71 
 
 Symptoms produced by, .... 66 
 
 Tartaric acid test for, .... 76 
 
 Tartrate, poisoning by, ... 71 
 
 Treatment of poisoning by, . . 69 
 
 Prussic acid 167 
 
 Pyromeconic acid, 485 
 
 Rats-bane, 240 
 
 Reagents, chemical, 59 
 
 Realgar, 240 
 
 Reinsch's test for arsenic, .... 269 
 Rodgers and Girdwood's method for 
 
 recovering alkaloids, 416 
 
 Rubidia, 65 
 
 Sabadilla, 643 
 
 Soda, density of solutions of, . . 83 
 General chemical nature, ... 83 
 
 Poisoning by, 66 
 
 Recovery from organic mixtures, 88 
 Special chemical properties, . 84-88 
 
 Solania, 657 
 
 Solanine, chemical properties of, . 660 
 
 History, 657 
 
 Preparation, 657 
 
 Post-mortem appearances, . . . 660 
 Recovery from organic mixtures, 667 
 Solubility, 661 
 
SOL— TOB 
 
 701 
 
 PAGE. 
 
 Solauine, symptoms produced by, 1 . 660 
 
 Treatment of poisoning by, . . 660 
 
 Solanum dulcamara, symptoms of, 658 
 
 Nigrum, symptoms of, ... - 659 
 
 Tuberosum, poisoning by, . . . 659 
 
 Sonnenschein's test for ammonia, . 94 
 
 Sources of evidence of poisoning, . 39 
 
 Spectrum analysis 80 
 
 Spirit of salt, 138 
 
 Stas' method for recovering alka- 
 loids, 411 
 
 Stramonium, external application, 639 
 
 Poisoning by, 637 
 
 Post-mortem appearances, . . . 640 
 Symptoms produced by, . . . 637 
 Treatment for poisoning by, . . 640 
 
 St. Ignatius' bean, 534 
 
 Stomach, redness of, 46 
 
 Softening of, 46 
 
 Ulceration and perforation, . . 47 
 
 Strychnia, 534 
 
 Strychnic acid, 529 
 
 Strychnine, accumulative effects of, 540 
 
 Color test for, 553 
 
 Delicacy of, 555 
 
 Fallacies of, 560 
 
 Interferences with, .... 558 
 External application of, ... 539 
 Failure to detect, . .... 591 
 
 Fatal quantity, 542 
 
 Frog test for, 576 
 
 Galvanic test, 566 
 
 General chemical nature, . . . 548 
 
 History, 534 
 
 Period when fatal, 541 
 
 Physiological test for, .... 676 
 Poisoning, diagnosis of, . . . 540 
 Post-mortem appearances, . . . 546 
 
 Preparation, 535 
 
 Quantitative analysis, .... 593 
 
 Recovery from the blood, . . 587 
 
 From nux vomica, . ... 579 
 
 From organic mixtures, . . . 579 
 
 From the tissues, 586 
 
 From the urine, 590 
 
 By Dialysis, 582 
 
 Salts of, 550 
 
 Solubility, 549 
 
 Special chemical properties, . . 550 
 
 PAGE. 
 
 Strychnine, symptoms produced by, 536 
 
 Taste of, 551 
 
 Time of symptoms, 537 
 
 Treatment of poisoning by, . . 543 
 
 Strychnos Ignatii, 534 
 
 Sugar of lead, poisoning by, . . . 355 
 
 Sulphate of potash, 71 
 
 Sulphuric acid, density of solutions of, 105 
 
 Fatal quantity, 101 
 
 General chemical nature, . . . 104 
 
 Period when fatal, 99 
 
 Poisoning by, 98 
 
 Post-mortem appearances, . . .102 
 Quantitative analysis, . . . 119 
 
 Recovery from organic mixtures, 113 
 Separation from organic fabrics, 119 
 Special chemical properties, 106-113 
 Symptoms produced by, ... 98 
 
 Treatment of poisoning by, . . 101 
 
 Suspected poisoning, 41 
 
 Symptoms, as evidence of poisoning, 39 
 
 Tartar emetic, composition, . . . 216 
 
 Fatal quantity, 219 
 
 General chemical nature, . . . 221 
 
 Period when fatal, 218 
 
 Post-mortem appearances, . . . 220 
 
 Quantitative analysis, .... 237 
 
 Recovery from organic mixtures, 233 
 
 From the tissues, 236 
 
 Solubility, 221 
 
 Special chemical properties, 222-233 
 
 Symptoms produced by, . . . 216 
 
 Treatment 220 
 
 Tartrate of potash, poisoning by, . 71 
 Tetanus, distinguished from poison- 
 ing, 540 
 
 Thornapple, . . . . 636 
 
 Tincture of opium, poisoning by, 458 
 
 Tobacco, chemical properties of, . 428 
 
 Detection in organic mixtures, . 437 
 
 External application of, ... 425 
 
 Fatal quantity, 427 
 
 Period when fatal, ... . 426 
 
 Poisoning by, 423 
 
 Post-mortem appearances, . . . 427 
 
 Smoking of, 425 
 
 Symptoms produced by, ... 424 
 
 Treatment of poisoning by, . 427 
 
702 
 
 USL— ZIN 
 
 \ PAGE. 
 
 UsLAR and Erdmann's method for 
 recovering alkaloids, 417 
 
 Valser's method for the recovery of 
 morphine, 498 
 
 Vegetable alkaloids, 409 
 
 Poisons, general considerations, 409 
 
 Veratria, 643 
 
 Veratrine, chemical properties, . . 648 
 
 History, 643 
 
 Poisoning by, 645 
 
 Preparation, 643 
 
 Recovery from organic mixtures, 656 
 
 From the Wood, 657 
 
 Salts of, 650 
 
 Solubility, 650 
 
 Test for sulphuric acid, . . . 112 
 
 Veratrum album, 643 
 
 Postmortem appearances, . . . 646 
 
 Sabadilla 648 
 
 Treatment, 648 
 
 Viride, poisoning by, .... 646 
 
 PAOE, 
 
 Verdigris, 374 
 
 Vomiting, effects of, 57 
 
 White hellebore, poisoning by, . . 645 
 
 White vitriol, 393 
 
 Wolfsbane, 606 
 
 Woorara, properties of, 561 
 
 ZiNO, chloride of, 394 
 
 History and chemical nature, . . 392 
 
 Of solutions of, 398 
 
 Post-mortem appearances, . . . 396 
 Properties of salts of, .... 397 
 Quantitative analysis, .... 405 
 Recovery from organic mixtures, 404 
 
 Salts of, 393 
 
 Special chemical properties, 398-403 
 
 Sulphate of, 393 
 
 Symptoms produced by, . . . 394 
 Treatment of poisoning by, . . 396 
 Use of for culinary purposes, . 396 
 
 THE END. 
 
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