"^Jk^m^x W'W 'i^§M^0§jii0W§Mi& F m 53 hJ47 THIS, BOOK I k S THE GIFT OF / Clu5 C^ Digitized by Microsoft® RB 53^4^°™"""'""!!/ Library 'llwlllMiimf 1"3'''a«ve and quantitat 3 1924 000 887 129 DATE DUE ^^I^Sd^ sy^?^^ ^ GAYLORD PRINTED IN U.S.A. Digitized by Microsoft® This book was digitized by Microsoft Corporation in cooperation witli Cornell University Libraries, 2007. You may use and print this copy in limited quantity for your personal purposes, but may not distribute or provide access to it (or modified or partial versions of it) for revenue-generating or other commercial purposes. Digitized by Microsoft® Digitized by Microsoft® Digitized by Microsoft® A GUIDE TO THE QUALITATIYE AND QUANTITATIYE ANALYSIS OF THE URINE DESIGNED FOK PHYSICIANS, CHEMISTS AND PHARMACISTS BY Dr. C. NEUBAUER Professor, Chief of the Agricultural- Chemical Laboratory, and Docent in the Chemical Laboratory in Wiesbaden AND De. J. YOGEL Professor (f Medicine in the Univeraity at EaUe ■WITH A PREFACE BT Pkof. De. E. FEESENIUS TEANSLATBD FROM THE SEVENTH ENLARGED AND REVISED GERMAN EDITION BY ELBRIDGE G. CUTLER, M.D. Physician to Out Patients at the Massachusetts General Hospital, Pathologist at the Boston City Hospital, and Assistant in Pathology in the Medical School of Harvard University , REVISED BY EDWARD S. WOOD, M.D. '' Professor of Chemistry in the Medical School of Harvard University NEW YORK WILLIAM WOOD & COMPANY 1879 Digitized by Mhrosoft® /e^ COPYKIGHT, A/47 By William Wood & Co. New York: J. J. Little Sz Co., Printers, 10 to 20 Astor Place. Digitized by Microsoft© PEEFAOE TO THE FIEST EDITION. Mr. C. Neubaxieb, assistant in my laboratory, having been requested by a number of the physicians of the city, has given them a series of lectures on the analysis of the urine, which has recently undergone complete remodelling, and is constantly assuming a greater importance. These lectures gave the first origin to this book. Since Neubauer has labored with great diligence on the basis of the newest investigations, and has himself tried all of the accepted methods, it will prove very welcome both to physicians and to pharmacists and chemists who aid them, and will prove a reli- able guide to urinary analysis. The publisher has spared neither cost nor pains in preparing the book ; all apparatus is illustrated by fine wood-cuts, and the appearances of the most important normal and abnormal constituents of the urine are depicted in truly excellent plates, so that the work is to be highly recommended in this respect. Pbof. Dk. e. fresbnius. Wiesbaden, April 5, 1854 Digitized by Microsoft® Digitized by Microsoft® PEEFAOE TO THE SEVENTH EDITION. In revising the present seventli edition of my Analysis of the Urine, I have honestly tried my best to take account of the progress of science. In the first three divisions, therefore, I have carefully added all reactions and methods which have been approved by myself or others. Among the new additions are the chapters on brenzcatechin, acetone, and the two patho- logical coloring matters discovered by Baumstark, urorubro- hsematin and urofuscohsematin. The fourth division, which treats of the accidental constitu- ents of the urine, has been considerably enriched. It is evi- dent, at first sight, how important are the physiological and pathological changes which substances undergo in their pas- sage through the system, and, therefore, we gladly see that a considerable activity has been developed in this part of urinary analysis during the last few years. Also the second part, which includes the methods of quanti- tative analysis, has been considerably enlarged. I mention the handy and delicate method of determining the specific gravity by the Mohr-Westphal balance, the Knop-Hiifner method of determining the urea, which is very good and easily performed in many cases, and also Bunge's modification of Bunsen's method for the same purpose, which, according to re- cent experience, is found to be indispensable in many cases where Liebig's method failed. Also, I could not refuse a place to the new method of determining chlorine by Yolhard and Talk, which is not inferior to Mohr's in accuracy. In the op- tical estimation of sugar, I have considered, besides the polari- scope of Ventzke-Soleil, that of Wild, which has decided ad- vantages over the former, and admits of an accuracy which I, V Digitized by Microsoft® Vi PREFACE TO THE SEVENTH EDITION. at least, have been unable to attain with the apparatus of Ventzke-Soleil. Also, the estimation of sugar from the dif- ference in specific gravity before and after fermentation, will not be entirely unwelcome to many physicians who are not conversant with volumetric analysis, and who do not have the expensive optical apparatus at their command. Lastly, I men- tion the new method of determining iodine by Hilger, and the method of Salkowski for estimating uric acid. With regard to the formulas which I use, I have given them both in the old and new nomenclature, and have desig- nated the new atomic weights by large type and crossed capi- tals, to do Justice to the old as well as the new friends of my book. I have received from different sources reprints of articles on the subject of urinary analysis, by which the review of the chemical, medical, and physiological current literature of the scattered material has been rendered essentially easier. I most heartily thank all who have aided me in this labor, and, at the same time, beg that they will be as kindly thoughtful in the future. " May this new edition receive the same friendly acceptance and favorable criticism which has been its lot before. C. NEUBAUER. Wiesbaden, October, 1875. Digitized by Microsoft® EETISEE'S PEEFACE. The want of a practical manual and suitable text-book upon the analysis of the urine in the English language has long been felt. This want has, during the past few years, been partly supplied by Dr. Tyson's excellent little " Guide to the Practical Examination of Urine," which, however, is not, and does not pretend to be, a complete manual upon urinary chemistry. The medical student and practitioner need to know something more than simply the methods which are required to obtain a knowl- edge of the chemical composition of the urine. They should be able to infer from it, to a certain extent, the general condi- tion of the patient whose urine is examined, and it is hoped that the present work may accomplish for the English reader, what the original has for the German student, viz., show him exactly what inferences may be drawn from a knowledge of the chemical composition of the urine, and in what way and to what extent a knowledge of the changes going on within the body may be learned by examining the urine. There is no book in the English language which treats the subject of urinary chemistry in so thorough and scientific a manner, and in none is the material so arranged as to be readily available to both student and practitioner. The separation of the book into two distinct parts, the first by Dr. Neubauer being strictly chemical, and the second by Dr. Vogel being chiefly medical, adds much to its value as a book of reference for both the chemist and physician. vii Digitized by Microsoft® viii REVISER'S PREFACE. Since tlie former translation of Neubauer and Vogel, pub- lished by tlie New Sydenham Society in 1863, such vast pro- gress has been made in the domain of organic and physiological chemistry, that the original work has passed through four edi- tions, and the 1863 translation by no means represents the present standpoint of urinary chemistry. The present (seventh) edition contains the most recent advances culled from the cur- rent literature of the day. Some difficulties have been met with in the translation, which all who have done the same kind of work can appreciate. The translation has been made as literal as possible to be consistent with clearness, and elegance of style has not been aimed at. Boston, 1879. Digitized by Microsoft® TABLE OF OOI^TEl^TS. PART FIRST. BY C. NEUBAUEE. DIVISION FIRST, I. PAGE § 1. Physical and Chemical Properties of Normal Urine 3 II. Normal Constituents of the TJkinb. A. Organie. §3. Urea 11 A. Presence 11 B. Preparation 18 1. Prom Urine 13 3. Prom Cyanate of Ammonium ■ 14 C. Microscopic Properties 14 D. Chemical Properties 14 Nitrate of Urea 17 Oxalate of Urea 17 Phosphate of Urea. 18 E. Detection 18 § 3. Kreatinin 19 A. Presence 19 B. Microscopic Properties 30 C Chemical Properties 30 D. Preparation of the Chloride of Kreatinin from Urine 23 E. Detection 34 § 4. Kreatin .\ . . . 35 A. Presence 35 B. Preparation 36 C. Microscopic Properties 36 D. Chemical Properties 37 E. Detection 38 § 5. Xanthin 38 A. Presence 38 ix Digitized by Microsoft® TABLE OF CONTENTS. PAGE B. Microscopic Properties 29 C. Cliemical Properties 29- D. Detection 81 1. Xanthin 31 3. Kreatinin 33 3. Urea 33 Appendix — Hypoxanthin (Sarkin) 33 §6. Uric Acid 35 A. Presence 35 B. Preparation 36 1. From Human Urine 36 3. From Excrement of Serpents 36 C Microscopic Properties 37 B. Chemical Properties 37 E. Detection 41 § 7. Oxaluric Acid 43 A. Presence 43 B. Preparation 43 C. Microscopic Properties 43 D. Chemical Properties 44 E. Detection 45 § 8. Hippuric Acid 47 A. Presence 47 B. Microscopic Properties 49 C. Preparation 49 D. Chemical Properties 50 E. Detection 51 Succinic Acid 53 § 9. Phenol (CarboUo Acid, Phenylic Acid, Phenylic Alcohol) 55 ' A. Presence 55 B. Chemical Properties 56 1. TaurylicAcid 57 3. Damaluric Acid 57 3. Damolic Acid 57 Detection and Separation of the four Acids 58 1. Collectively 58 3. Individually 58 G. Detection m Human Urine 59 §10. Urinary Coloring Matters 60 I. Urobilin 60 A. Presence 60 B. Separation and Properties 60 C. Occurrence in Normal Urine 63 II. Urochrom 64 A. Preparation 65 B. Properties 66 III. Uroxanthin (Heller)— Indioan (Sohunk) 67 A. Preparation 68 Digitized by Microsoft® TABLE OF GONTMNTS. xi PAGE rV. Uroglauoin and Urrhodin , 68 (Indigo blue and indigo red.) a. Urrhodin (indigo red) 69 6. Uroglauoin (indigo blue) 69 A. Preparation by the Method of Schimk 70 B. Preparation by the Method of Kletzinsky and Keller 70 C. Detection 71 V. Uroerythrin 73 VI. Black Urine 74 § 11. Kryptophanie Acid 74 § 13. B. Inorgcmic. 76 § 13. Chloride of Sodium 76 A. Presence 76 B. Microscopic Properties 77 C. Chemical Properties 77 B. Detection 79 § 14. Chloride of Potassium 79 § 15. Sulphates 80 A. Presence 80 B. Chemical Properties 80 C. Detection 81 § 16. Acid Phosphate of Sodium 81 A. Presence 81 B. Chemical Properties 82 C. Detection ! 83 § 17. Phosphates of Calcium and Magnesium .- 83 Detection 84 §18. Iron 84 A. Presence 84 B. Chemical Properties 85 C. Detection 85 § 19. Ammonium Salts 86 Detection 87 § 20. Silicic Acid 88 § 31. Nitrates and Nitrites., 88 § 22. Hydrogen Peroxide 89 Detection in Urine 90 III. Abnormal Constituents of Ubinb, § 33. Albumen (Serum Albumen) 91 A. Presence 91 B. Preparation of Pure Albumen 91 C. Chemical Properties 93 D. Preparation of Albumen absolutely free from Salts by Diffu- sion ; 94 E. Detection 95 Digitized by Microsoft® Xii TABLE OF CONTENTS. PAGE § 24. Supplement 97 1. Fibrine 97 3. Casein 98 8. Albuminose 98 4. Paralbumen and Paraglobulin 99 Detection of Paraglobulin in Albuminous Urines 99 5. Peptone 100 Detection of Peptone in Albuminous Urines 100 6. Nephrozymose 100 § 25. Urinary Sugar — Grape Sugar 101 A. Presence 101 B. Microscopic Properties 103 C. Preparation of Chemically Pure Grrape Sugar 103 D. Chemical Properties 103 a. Saccharate of Potassium 103 h. Saccharate of Calcium 103 c. Compound of G-rape Sugar with Chloride of Sodium 103 E. Detection 106 § 26. Alkapton 114 § 37. Inosite 114 A. Presence 114 B. Microscopic Properties 115 C. Chemical Properties 115 B. Detection 116 § 38. Biliary Substances 117 Biliary Coloring Matters 118 A. Presence 118 B. Preparation 118 C. Chemical Properties 118 a. Bilirubin (Cholepyrrhin) 118 l. Biliverdin 130 c. Biliprasin 120 d. Bilif uscin 121 B. Detection 121 § 39. Biliary Acids 124 1. Taurocholic Acid 124 3. Glycocholic Acid 125 A. Chemical Properties 126 B. Detection 127 § 30. Lactic Acid 130 A. Presence 130 B. Chemical Properties 131 1. Lactate of Calcium 132 3. Lactate of Zinc 132 O. Detection 132 § 31. Volatile Fatty Acids I34 I. Formic Acid I34 II. Acetic Acid I35 Digitized by Microsoft® TABLE OF CONTENTS. xiii PASS III. Propionic Acid 135 IV. Butyric Acid 136 V. Baldrianic Acid 137 Detection of the Patty Acids 137 § 32. Benzoic Acid 138 A. Presence 138 B. Microscopic Properties 139 C. Chemical Properties 139 D. Detection 140 § 33. Pats 140 A. Presence , 140 B. Microscopic Properties 141 C. Detection , 141 § 34. Sulphuretted Hydrogen .^ 142 §35. AUantoin 144 A. Presence 144 B. Preparation 144 C. Microscopic Properties 145 D. Chemical Properties 145 E. Detection 145 Alloxan 146 §86. Leucin 147 A. Presence 147 B. Microscopic Properties 147 C. Chemical Properties 147 D. Detection and Preparation 148 § 37. Tyrosin 149 A. Presence 149 B. Microscopic Properties 149 C. Chemical Properties 149 D. Preparation 150 E. Detection , 152 § 38. Oxymandel Acid 153 A. Presence 153 B. Detection and Properties 154 § 39. Brenzcatechin (Oxyphenic Acid) 155 § 40. Urorubrohaematin and Urof uscohaematin 156 § 41. Acetone, Alcohol, and Bthyldiacetic Acid 157 Detection 157 Derivation of the Acetone and Alcohol 158 IV. § 43. Ueinaey Sediments. 159 /. Non-Organized, Sediments. 162 § 43. Uric Acid 162 §44, Urates 163 1. Acid Urate of Sodium 164 2. Acid Urate of Potassium 164 Digitized by Microsoft® xiv TABLE OF CONTENTS. PAGE 3. Acid Urate of Ammonium 164 4. Aoid Urate of Calcium 1^5 §45. Oxalate of Calcium. 165 A. Presence 165 B. Microscopic Properties 166 C. Detection 167 § 46. Earthy Phosphates 168 1. Ammonio-Magnesian Phosphate 168 3. Phosphate of Calcium 169 § 47. Cystin 171 A. Presence 171 B. Microscopic Properties 173 C. Chemical Properties 173 D. Detection « 173 § 48. Tyrosin 174 § 49. Xanthin (Hypoxanthin ?) 174 II. § 50. Mucus and Epithelium 175 § 51. Blood 178 A. Microscopic Properties 178 1. Action of Water on Blood Corpuscles 178 3. Action of Saline Solutions on Blood Corpuscles 179 8. Action of Alkalies on Blood Corpuscles 179 B. Detection 180 1. The Urine contains Blood Corpuscles 180 3. The Blood Corpuscles are destroyed ; the Urine contains Methsemoglobin 180 § 52. Pus 183 A. Microscopic Properties 188 1. Action of Water on Pus Corpuscles 183 3. Action of Acetic Acid on Pus Corpuscles ■ 183 3. Action of Alkalies on Pus Corpuscles 184 B. Detection 184 § 53. Casts 185 § 54. Spermatozoa 186 § 55. Fungi. Infusoria 187 V. § 56. AccroBNTAL Constituents of the Ueinb. 190 /. Inorganic Substances. 193 A. Salts of the Heavy Metals 193 Mercury 193 Thallium 195 Cadmium 195 -B. Free Mineral Acids 196 C. Salts of the Alkalies 196 B. Salts of the Alkaline Earths 198 Digitized by Microsoft® TABLE OP CONTENTS. X7 PAOE 11. Organic Substances. 198 A. Free Organic Acids 198 B. Indifferent Substances 200 C. Salts of the Organic Acids 203 D. Organic Bases 204 E. Coloring and Odorous Matters 209 DIVISION SECOND. QUANTITATIVE ESTIMATIONS. § 57. Estimation of the amount of Urine secreted in a given time 210 § 58. Specific Gravity 211 1. By the Araeometer (ITrinometer) 211 2. With the Mohr-Westphal Balance 213 3. With the Picnometer 214 § 59. Estimation of the Water and the Total Solids 216 § 60. Estimation of the Non- Volatile Salts 221 § 61. Estimation of the Coloring Matters 222 A. The Color Table 232 B. Value of the Color Scales 223 C. AppUcation of the Method 234 QUANTITATIVE ESTIMATION OF INDIVIDUAL SUBSTANCES. § 63. Volumetric Analysis 325 § 68. I. Apparatus 226 1. Graduated Pipette 336 2. Mohr's Pipette 237 3. Graduated Burette 229 4. Graduated Cylinder 229 § 64. II. Performance 230 § 65. Estimation of Urea 233 1. By Liebig's Method 233 A. Principle 232 B. Preparation of the Solutions 333 1. Standard Urea Solution 233 3. Standard Mercuric Nitrate Solution 333 3. Baryta Solution 235 C. Performance ■. 235 D. Modification of the Process and Corrections required by differ- ent circumstances 236 1. The Urine contains more than 2 per cent, of Urea 236 2. The Urine contains less than 2 per cent, of Urea 237 3. The Urine contains Chloride of Sodium 237 4. The Urine contains Albumen 239 5. The Urine contains Carbonate of Ammonium 340 Digitized by Microsoft® xvi TABLE OF CONTENTS. PAGE 3. By the Knop-Hiifner Method 342 A. Principle 343 B. Preparation of the Hypobromite of Sodium Solution 343 C. Performance 343 3. Buusen's Method modified by G. Bunge 344 § 66. Estimation of Chlorine (Chloride of Sodium) 345 I. Mohr's Method 345 A. Principle 345 B. Preparation of the Solutions 346 1. Standard Nitrate of Silver Solution 346 3. Potassium Chromate Solution. 347 C. Performance 347 1. Modification in Urine containing Iodine and Bromine 348 II. Method of J. Volhard and A. FaloJs 348 A. Principle 348 B. Preparation of the Solutions 349 1. Standard Nitrate of Silver Solution 349 3. Solution of Iron Oxide 349 3. Standard Sulphooyanide of Potassium Solution 349 C. Performance 250 § 67. Estimation of Phosphoric Acid 350 A. Principle 350 B. Preparation of the Solutions 253 1. Standard Phosphoric Acid Solution 253 3. Acetate of Sodium Solution 353 3. Standard Uranium Solution 253 G. Performance 353 a. Estimation of the Total Phosphoric Acid 353 h. Estimation of the Phosphoric Acid combined with the Alka- line Earths 255 § 68. Estimation of the Degree of Acidity 256 A. Principle 256 B. Preparation of the Solutions 256 1. Standard Oxalic Acid Solution 356 3. Tincture of Litmus 256 3. Standard Sodic Hydrate Solution 356 O. Performance 357 § 69. Estimation of Sulphuric Acid 357 A. Principle 357 B. Preparation of the Solutions 358 1. Standard Chloride of Barium Solution 258 3. Standard Sulphate of Potassium Solution 359 0. Performance 359 § 70. Estimation of Sugar 361 1. By Pehling's Method 361 A. Principle 361 B. Preparation of the Copper Solution 362 C. Performance 363 Digitized by Microsoft® TABLE OF CONTENTS. xvii PAGE 3. By Knapp's Method 365 A. Principle 365 B. Preparation of the Mercuric Cyanide Solution 265 C. Performance 365 3. By Circumpolarization 366 A. With the Ventzke-Soleil Polarizer 366 B. With the Polarizer of Wild 371 4. By Fermentation 276 5. Prom the Difference in Specific Gravity before and after Fer- mentation 377 § 71. Estimation of Iodine 278 1. By Kersting's Method 378 A. Principle 378 B. Preparation of the Solutions 379 1. Standard Iodide of Potassium Solution 379 3. Standard Chloride of Palladium Solution 379 C. Performance 380 3. By Hilger's Method 383 3. Colorimetric Estimation by Struve's Method 383 A. Principle 283 B. Preparation of the Color Scale 383 C. Performance 284 §72. Estimation of Iron 285 A. Principle 385 B. Preparation of the Solutions 385 1. Permanganate of Potassium Solution 285 2. Ferrocyanide of Potassium Solution 386 C. Performance 386 § 73. Estimation of Uric Acid 287 1. By Precipitating with Hydrochloric Acid. 387 3. By Salkowski's Method 390 § 74. Estimation of Kreatinin 391 A. Principle 391 B. Preparation of Chloride of Zinc Solution 391 C. Performance 293 § 75. Estimation of Albumen 393 A. Grravimetrie Method 393 B. By Circumpolarization 396 1. Badeker's Method 397 2. Vogel's Optical Method , 397 3. Methods of Lang, Haebler, and Bernhardt 397 4. Mehu'sMethod 398 5. Liborius's Method 298 6. Girgensohn's Method 299 § 76. Estimation of Calcium and Magnesium 299 I. Estimation of the Calcium 299 A. Principle 399 B. Preparation of the Solutions 399 B Digitized by Microsoft® xviii TABLE OF CONTENTS. PAGE 1. Standard Hydrochloric Acid 399 2. Standard Sodic Hydrate 300 C. Performance 301 II. Estimation of the Magnesium 303 Gravimetric 302 Volumetric 304 III. Indirect Estimation of Calcic and Magnesic Phosphates 304 § 77. Estimation of Ammonia 306 A. Principle 306 B. Preparation of the Solutions 306 1. Standard Sulphuric Acid 306 3. Standard Sodic Hydrate 307 O. Performance 307 § 78. Estimation of Ammonia and Potash with Platinic Chloride 308 § 79. Estimation of Potassium and Sodium 310 A. Direct 310 B. Indirect 311 § 80. Estimation of Carbonic Acid 313 § 81. Estimation of the Total Nitrogen 313 A. Principle 314 B. Preparation of the Solutions 314 C. The Distilling Apparatus 315 D. Performance 315 § 83. Estimation of the Pat 318 § 83. Estimation of Biliary Acids 318 § 84. Estimation of Indican by Jaffe's Method 319 § 85. Estimation of Oxalic Acid 331 DIVISION" THIED, ■ I. ) 86. Qualitative Analysis. 333 ) 87. Systematic Process for Detecting the Soluble Constituents 333 II. j 88. Recognition of Sediments under the Microscope. 329 A. The Urine is Acid 330 1. Amorphous 330 2. Crystalline 331 3. Organized 333 B. The Urine is Alkaline 334 1. Crystalline 334 2. Amorphous 334 3. Organized 334 ! 89. Preservation of Urinary Sediments 334 Digitized by Microsoft® TABLE OF 00NTENT8. xix III. PAGE § 90. Quantitative Analysis. 337 IV. § 91. Approximate Estimations. 844 1. Estimation of the Earthy Phosphates by Beneke's Method. . 344 2. Estimation of Calcic Oxalate by Beneke's Method 346 § 92. Analytical Experiments 347 I. Table for Estimating the Total Solids from the Specific Grravity. 347 II. Chlorine Analyses 348 III. Phosphoric Acid Analyses 349 IV. Sulphuric Acid Analyses 349 V. Sugar Analyses 350 VI. Kreatinin Analyses j 351 VII. Albumen Analyses 351 VIII. Calcium Analyses 35I IX. Ammonia Analyses 353 PART SECOND. BY JULIUS VOaEL. Intkoduotion 356 DIVISION FIRST. I. Changes in the Colob, Appearance, and Odor op the Urine. . 363 §93. Color of the CJrine 363 1. Normal 363 2. Abnormal 365 a. Essential 365 1. Blood Pigment 365 2. Biliary Pigment 366 3. Indioan 366 4. Uroerythrin 868 6. Accidental 368 § 94. Odor of the Urine 369 § 95. Transparency of the Urine 370 II. §96. Chemical Reaction of the Urine. 370 1. Acid 376 2. Neutral or Alkaline 377 Digitized by Microsoft® XX TABLE OF CONTENTS. III. PAGE Unusual (Abnormal) Constituents. 378 § 97. Albumen 379 A. Detection 379 B. Significance 381 1. Globulin or ParaglobuHn 384 3. Alkali Albuminate 384 3. Peptone 384 § 98. Fibrine 388 §99. Bloodinthe Urine 389 A. Detection 389 B. Importance 390 § 100. Dissolved Blood— Dissolved Haematoglobulin 392 Importance 394 §101. Pat 395 A. Detection 395 B. Importance 396 § 103. Biliary Pigments 398 § 103. Biliary Acids 398 § 104. Sugar 400 Importance 403 § 105. Accidental Abnormal Constituents 406 Lead 407 Copper 407 Zinc 408 Nickel and Cobalt 408 Arsenic and Antimony 408 Tannic Acid 408 Alcohol, Carbolic Acid, and Chloroform 408 Quinia 409 IV. § 106. Urinary Sediments. 409 A. Non-Organized. % 107. Uric Acid and Urates 410 § 108. Hippuric Acid 4^4 § 109. Earthy Phosphates 41g § 110. Oxalate of Lime. Calcic Oxalate 418 Causes and Importance 419 §111. Cystin 423 § 113. Xanthin — Hypoxanthin — Tyxosin 434 B. 09-ganized. § 113. Mucus and Epithelium 435 § 114. Pus '.'..'.'.'..'."." .".7. .".".' ! 428 § 115. Cancerous and Tuberculous Masses 43O Digitized by Microsoft® TABLE OF CONTENTS. xxi PAGE § 116. Urinary Cylinders — Renal Casts 434 1. Epithelial Casts 434 2. Granular Casts 434 3. Hyaline Casts 435 Blood Corpuscles 437 § 117. Infusoria — Fungi — Kyesteine 437 § 118. Spermatozoa ; . 440 Entozoa 440 DIVISION SECOND. § 119, QUANTITATIVB CHANGES IN THE UbINE. ■ 443 I. Quantitative Alterations of the Urine which are easily Demonstrated. 444 § 130. Quantity of Urine 444 Variation in Disease 451 § 121. Solid Residue and Specific Gravity 453 § 122. Quantity of Urinary Pigment 461 § 123. II. Quantitative Alterations of the Urine which require a compli- cated Chemical Analysis for their Demonstration 465 § 124. General Rules for the Quantitative Analysis of Urine 467 § 125. Urea 473 § 126. Uric Acid 481 § 127. Free Acids 484 § 128. Ammonia 486 § 129. Chlorine and Chloride of Sodium 489 § 130. Sulphuric Acid 497 § 131. Phosphoric Acid 504 § 133; Earthy Phosphates 511 § 138. Potassium 515 Kreatinin 515 Leucin and Tyrosin 516 AUantoin 517 Lactic and Oxymandel Acids 517 Carbonic Acid 517 § 134. Concluding Observations 518 (Illustrative Cases.) APPENDIX. § 135. Introduction to the Examination of Urinary Calculi and other Urinary Concretions 531 Description of the Plates 540 Digitized by Microsoft® Digitized by Microsoft® INTEODUCTIOK With the rapid development of chemistry in the last few decades, its reaction upon other arts and sciences has been manifest. Where do we find now a rational manufacturer or farmer who does not constantly appeal to chemistry, so much is he impressed with its importance ? Who can question the important services it has rendered medical science, already? Physiology and pathology owe a great part of their rapid growth of late years to the development of this young science. How simple have the processes of respiration and nutrition become, since chemistry with balance and weights has deter- mined the metamorphosis ! Physiologists' and physicians have long recognized the importance of the earnest study of this process, and have turned their attention to the investigation of the rapidity of the transformation of tissue. Zooehemical analysis, through the earnest zeal of so many observers, has naturally flourished and rapidly developed. It soon taught that the urine was the special storehouse for the decomposition products of animal tissues, and that its study would give conclusive information concerning the organic pro- cesses in the diseased as well as in the healthy body. This secretion has, therefore, been investigated with great diligence, since the first origin of zooehemical analysis. Many substances were discovered in it, and many appearances observed which permitted conclusions to be drawn concerning the function of the organism. Unfortunately, until within a short time, the analysis of the urine was a very protracted and laborious undertaking, and could not be performed by practising physicians. How different has this become in modern times ! It is now possible for medi- cal men, furnished with the simplest and most accurate methods, xxiii Digitized by Microsoft® xxiv INTRODUCTION. to test the urine at the bedside in a short time, either for the discovery of a few abnormal constituents, or for determining the quantity of several of the normal contituents. If, in addi- tion, the microscope be used rationally, all the conditions are given for an accurate determination of the changes in the organ- ism from the composition of the urine. In the following pages I shall first give a description of nor- mal urine, and at the same time call attention to the peculiar -changes which it undergoes in the acid and alkaline fermen- tation. The chemical properties of the normal and abnormal, organic and inorganic constituents is added to the first part, in which I shall pay special attention to the appearances of each under the microscope. The second part treats exclusively of the different quantita- tive methods, with a detailed account of the necessp-ry precau- tions, manipulations, and contingent modifications. The third part, on the other hand, contains a practical guide to the qualitative and quantitative examination of the urine and its sediments, in accordance with the present stand- point of chemistry. The following is a summary of the entire contents : I. Division. 1. Physical and chemical properties of normal urine. 2. Normal constituents. a. Organic. 6. Inorganic. 3. Abnormal constituents. 4. Sediments. 5. Accidental constituents. II. Division. Quantitative estimation of the various organic and inorganic constituents. m. Division. 1. Practical guide to qualitative analysis. 2. Eecognition of sediments under the microscope. 3. Practical guide to quantitative analysis. 4. Practical guide to the approximate quantitative esti- mation. Analytical notes. Digitized by Microsoft® PART FIRST. A TREATISE ON THE CHEMICAL AND MICROSCOPICAL CHARACTERISTICS AND PROPERTIES OF THE URINARY CONSTITUENTS ; TOGETHER WITH A GUIDE TO THE QUALITATIVE AND QUANTITATIVE CHEMICAL EXAMINATION OP NOEMAL AS WELL AS ABKOEMAL UEINE. GAEL NEUBAUER. Digitized by Microsoft® Digitized by Microsoft® Analysis of the Ubine. DIVISION FIEST. I. PHYSICAL AND CHEMICAL PROPERTIES OP NORMAL URINE. § 1. It is an established fact tliat the urine, physiologically con- sidered, is a true secretion by organs specially adapted for that purpose, the kidneys. We find in it, in the form of soluble nitrogenous and saline compounds, those elements which by transformation hare become useless to the economy. Generally considered, the constituents of normal urine may be regarded principally as the products of metamorphosis of the animal tissues, etc. Most important are the organic nitroge- nous constituents of the urine : urea, uric acid, hippuric acid, oxaluric acid, kreatinin and xanthin, besides the coloring and extractive matters. Of these in human urine, urea occupies the first place ; it is the most important product of retro- grade metamorphosis of the nitrogenous constituents of the body, from which it is formed by the oxidizing power of the organism in a manner yet unknown, since hitherto it has not been possible, in spite of many attempts, to produce urea arti- ficially by the action of energetic oxidizing agents * on protein substances. Indeed, several facts indicate that, in the oxidation of the * The repeated assertion of Bechamp that urea may be formed by the action of permanganate of sodium on protein bodies has not been confirmed by Stade- ler, Loew, and myself. 3 Digitized by Microsoft® 4 ANALYSIS OF THE URINK different varieties of albumen, in the economy, its nitrogen is not directly converted into the form of urea, but previously a number of intermediate products are formed, which, by further decomposition, furnish urea. Thus, O. Schultzen and Nencki * found that leucin and glycocoU, even when ' rapidly absorbed into the economy in large amounts, were eliminated in the form of urea ; and, according to the experiments of Von Kmeriem,t ammonium chloride, asiparagin, and asparagic acid, which latter was discovered by Badziejewski and E. Salkowski to be the product of the digestion of fibrine by the pancreatic ferment, likewise cause an increase of urea in the urine. In the same way, in those diseases in which oxidation is much impaired, as acute yellow atrophy of the liver, etc., very large quantities of leucin and tyrosin are found in the urine, sub- stances which Kiihne showed were formed in large amount by the action of the pancreatic ferment on albuminates, while, in such cases, urea often wholly disappeared, and at the same time, paralactic acid, which, under normal conditions so readily oxidizes, was largely present. J Besides the above-named bodies, the mineral constituents of the blood, which have become physiologically useless, as well as many other substances entering into the economy, which are unnecessary for the process of metamorphosis, or are even injurious, are discharged with the urine, either unchanged or after chemical transformation. Finally, we must mention water, by the separation of which the kidneys regulate its amount in the blood, which is thus kept at a tolerably constant density. Normal urine, then, appears to be a very complex fluid, whose composition varies according to different classes of animals. Food exercises an undoubted influence on the composition of the urine, which is distinctly proved in the carnivora and herbivora. The urine of the former does not differ essentially from that of human beings. In the fresh state it is clear, light yellow, of unpleasant odor, bitter taste and acid reac- tion. The amount of urea is considerable, while the uric acid often entirely disappears, but soon increases, however, when * Berichte der deutsch. chem. Gesellsctaft, 1869, p. 566. f Zeitschrift fiir Biologie, Band 10, p. 263. % 0. Sctultzen und L. Riess : Uber acute Phosphorvergiftung und Lebera- trophie. Digitized by Microsoft® PROPERTIES OP NORMAL URINE. 5 tlie beasts are deprived of their free exercise, as -when confined in cages. Entirely different from this is the urine of the herbivora, which is characterized by its constant turbidity, alkaline reac- tion, and also by its considerable richness in carbonates of the alkalies and alkaline earths. It often contains a tolerable amount of urea, but is for the most part rich in hippuric acid : uric acid is often wholly absent, and also the phosphates occur in very small amount. Calcic oxalate, together with crystal- lized calcic carbonate, is always found in the sediment of this urine. The influence of food on the composition of the urine appears most distinctly when herbivora are forced to digest only ani- mal food, or when they are made to fast for a long time, so that life is maintained entirely at the expense of the constituents of their own bodies. The urine thereby very soon loses its alka- line reaction, it becomes acid, urea appears in considerable quantity, the sediment of calcic carbonate disappears, and uric acid in appreciable quantity is found. The urine, therefore, assumes the same character as that of the carnivora, a fact which can readily be demonstrated on rabbits.* Exactly the reverse occurs when carnivora are fed on a purely vegetable diet. The urine of birds, reptiles, etc., differs entirely from that of the mammalia, whence it must be inferred that the organiza- tion of these animals has a decided influence on the composition of the urine. Normal human urine shows, in general, more resemblance to that of the carnivora. Freshly passed it appears clear, of a light amber-yellow color, distinctly acid reaction, bitter, salty taste, and peculiar aromatic odor. Stadeler, in his great work, was the first to throw some light on the odorous matters in the urine, which work was chiefly on cow's urine, but included human urine- also. By distillation of large quantities he succeeded in recognizing a series of peculiar volatile acids as the cause of the odor in cow's urine ; among these are to be mentioned car- bolic acid, also taurylic, damoluric, and damolic acids. Human urine contains very much smaller amounts of these acids, and * Annal. der Chemie und Phann., Band 99, p. 106. Digitized by Microsoft® 6 ANALYSIS OF THE URINE. it is only by taking very large quantities for examination that we can succeed in distinctly recognizing carbolic acid by its char- acteristic reactions. But whether these acids, and especially the carbolic acid, either free or combined with an alkali, are really constituents of normal urine, appears, from the more recent investigations of Buliginsky * more than doubtful, since these rather indicate that the carbolic acid is produced by the action of mineral acids on evaporated urine from a substance hitherto entirely unknown. The specific gravity of normal human urine varies according to age and sex, constitution of body, and food, and varies from 1,005 to 1,030. There has been much dispute concerning the cause of the constant acid reaction of normal human urine, which, accord- ing to the investigations of Kliipfeht is considerably increased by strenuous muscular exercise, while Sawicki % could not de- termine that rest or work had any influence on its acidity ; finally Liebig proved that the acidity arose chiefly from the acid phosphates. Since the experiments of Lfehmann, there can be no doubt that in many cases free hippuric and lactic acids are found in the urine, which naturally contribute to the acid re- action. Under all circumstances the quantity as well as the quality of the food ingested has the greatest influence on the acidity of the urine. Since a solution of hyposulphite of sodium is immediately rendered turbid by a trace of free acid from the separated sul- phur, Huppert § made use of this salt with the best result to detect the presence of free acid, together with the acid salts, in a urine which has an acid reaction. Urea, which behaves like an ammonium compound with acids, and also, according to Lehmann's experiments, enters into fixed combinations with phosphoric acid, is, according to Huppert, not able to prevent the destructive action of acids on the hyposulphite of sodium, but only retards it. It is, therefore, to be considered that every urine, which, upon the addition of a solution of hyposulphite of sodium, immediately becomes cloudy, contains free acids free * Hoppe-Seyler, med. chem. Untersucliutigen, Heft 2, p. 334. f Hoppe-Seyler, med. chem. TJntersucliungen, Heft 3, p. 412. X Pflilger's Arcliiv, Band 5, p. 385. § Arcliiv der Heilkunde, Band 8, p. 354. Digitized by Microsoft® PROPERTIES OF NORMAL URINE. 7 acids in the sense that the collective bases in the urine, urea, etc. included, are not sufficient to form with them acid salts. If the separation of sulphur occurs only after a long time, there is, together with the ordinary acid salts, free acid present, which is in combination with urea. If, in urines which have an acid reaction, cloudiness does not occur at all on addition of the reagent, they contain only the ordinary acid salts. According to the investigations of O. Hammarsten * it appears, however, that variations in the amount of the hyposulphite of sodium added can change the results indefinitely, so that its value as a reagent for free acids and acid salts in the urine is somewhat doubtful. Urine can be kept for a long time in a closed vessel, pro- tected from contact with the air, without undergoing true de- composition. If we allow free access of air, however, it under- goes peculiar, not unimportant decompositions, which we 'will now consider more closely. If we leave fresh urine alone in an uncovered vessel, we perceive, in most cases very soon, the formation of light, small clouds of mucus, which gradually sink to the bottom, and in which we find with the aid of the micro- scope a few pavement epithelial cells from the bladder and urethra, as well as a very few mucus corpuscles enclosed in a finely granular coagulum of mucus. "We can also frequently readily see the separation of acid urates. On long standing, however, especially at a moderate temperature, the acid reac- tion frequently becomes stronger and distinct, and usually colored crystals of uric acid are deposited on the walls and bottom of the glass. It remains in this condition of increasing acidity for a few days at least, though it may last for two or even three weeks ; finally we notice that the acidity suddenly diminishes until it at last disappears entirely. The urine loses color, becomes lighter, and covered with a whitish iridescent pellicle, and gradually takes on an alkaline reaction, which is shown by an offensive ammoniacal odor. At this time the crystals of uric acid also disappear, and we see white granules and colorless, highly refractive, prismatic crystals of ammonio- magnesian phosphate. These changes are embraced under the names of the acid and alkaline fermentation of urine. * Jahresbericlit fur Tliierchemie, Band 4, p. 211. Digitized by Microsoft® 8 ANALYSIS OF THE URINE. Scherer has furnished interesting explanations of this decom- position; these are essentially as follows. He considers the primary cause of the acid fermentation of urine to be the Tesi- cal mucus, which he regards as a ferment necessary to the de- ^ composition of the extractive coloring matter ; the latter is de- composed by the mucus with the formation of lactic and acetic acids, so that an increase in the amount of the free acids is brought about. As an indication, and also, probably, as a cause of this act of fermentation, the urine now shows under the microscope considerable numbers of fermentation spores, which in appearance are very similar to those of yeast, only smaller, and which, like the latter, increase by budding, and are grouped together in rows. (Plate II., figs. 1, 2, and 4.) By the formation of these strong acids the readily decomposable urates are broken up with the separation of uric acid, which is then deposited in well-formed crystals. Almost always crys- tals of calcic oxalate are found in this sediment, concerning the formation of which I will speak more fully under sediments. (Plate II., fig. 4) If, after a longer or shorter time, the free acid begins to di- minish, then the second period of urinary fermentation, the alkaline, commences. Urea now suffers a decomposition, and becomes converted into carbonate of ammonium;* gradually the precipitated crystals of uric acid disappear, and whitish granules of urate of ammonium, and prismatic crystals of urate of sodium, which often cover the crystals of uric acid which are commencing to dissolve, appear instead. (Plate II., fig. 5.) As the decomposition increases and the alkaline reaction com- mences, a part of the ammonia combines with the phosphate of magnesium present in the urine, and very beautiful crystals of ammonio-magnesian phosphate, together with phosphate of calcium, separate in large amounts. (Plate II., figs. 3, 5.) This peculiar decomposition has the closest connection with the formation of sediments, and I shall return to it when I speak of them. * Together with carbonate of ammonium small amounts of other volatile bases, so-called substituted ammonias, appear to form also, of which Dessaignes has already observed trimethylamin, characterized by its odor of sea-fish, by the distillation of large amounts of human urine. (Annal. der Chemieund Pharm., Band 100, p. 138.) Digitized by Microsoft® / PB0PEBTIE8 OF NORMAL UBINE. 9 According to Voit and Hofmann* there is no acid fermenta- tion of urine, but only an alkaline one. The gradual separa- tion of amorphous and crystalline uric acid sediments they ex- plain by the decomposing action which the acid phosphate of sodium exerts on the urate of sodium, whereby the acid reac- tion of the urine gradually diminishes, so that at no time can an increase in acid be proved. This in many cases is undoubt- edly correct, but not in all. As soon as yeast spores occur in a urine, and such cases are not rare, the increase of acid can be readily determined, most easily in very weak saccharine as well as in diabetic urines in which sediments of crystallized uric acid frequently and rapidly form, in spite of the fact that in pronounced cases of diabetes the other constituents of the urine, not excepting the acid phosphate of sodium, are very much diluted. As a product of this fermentation, acetic acid appears, which can be readily separated from every old urine, especially from old diabetic urine, in considerable quantity. According to the investigations of Schonbein, there is a fungus in every urine which forms gradually and undergoes fermenta- tion, and which in a short time changes pure urea into carbon- ate of ammonium. According to Pasteur and Tieghem, a torula is present which forms in the interior of the fluid, especially on the bottom of the glass, as a white deposit. Under the mi- croscope this shows rosary-like strings or clumps of small round globules with a diameter of O'OOIS millim., without granula- tions or recognizable sheath, and which seem to increase by a process of budding. Of all the substances which occur in human urine, without doubt urea is by far the most important, and as we have already seen above, is essentially the final product of the retrograde metamorphosis of tissue. Urea forms the middle step by which the nitrogen, which has become useless in the body, is given back to inorganic nature, since, when once removed from the body, it decomposes very easily, in contact with decomposing matter, into ammonia and carbonic acid, to begin the circle anew in this form as food for plants. Next to urea comes uric acid, which is also the result of the metamorphosis of the nitrogen- ous constituents of the body ; it stands a step higher than urea, * Zeitschrift fur analyt. Oiem., Band 7, p. 397. Digitized by Microsoft® 10 ANALYSIS OF THE URINE. and decomposes by continuous oxidation into urea and carbonic acid. Its amount is very much less than that of urea, and it is not in a free state like the urea, but is in combination with bases. Besides uric acid, we meet also in all urine with small amounts of hippuric acid, the origin of which is not yet precise- ly proved, although it is probable that it is formed in a similar manner to urea and uric acid, and is an intermediate product in the process of retrograde metamorphosis. Besides these bodies, every urine contains, in addition, small amounts of xanthin, kreatinin, oxaluric acid, and coloring and extractive matters, about the chemical nature, origin, etc., of which but very little is yet positively known. Liebreich * claims to have found in urine a small amount of an organic base which has a resem- blance to neurin, obtained by him by the destruction of prota- gon by baryta water, and which possibly may be a product of the oxidation of the neurin. We also find of mineral constitu- ents, chlorides, chloride of sodium, chloride of potassium, and small amounts of chloride of ammonium, besides phosphates, especially acid phosphate of sodium and small quantities of magnesium and calcium phosphates and sulphates, traces of iron and silicic acid. Schonbein has also detected small quan- tities of nitrates, which in the alkaline fermentation of the urine are converted into nitrous acid, likewise traces of peroxide of hydrogen. A certain not altogether inconsiderable amount of carbonic acid from the blood, flowing through the urinary or- gans, gets into ^he urine and is eliminated with it. According to Bechamp, all normal urine contains also a pecu- liar ferment, nephrozymose, which, like the ferment of saliva, is capable of changing starch into sugar. Finally, that consti- tuent of the urine, which, under certain conditions, as I first discovered after the addition of a solution of chloride of zinc, shows a beautiful emerald-green fluorescence, has been recently more carefully investigated by Jaffe,t and since he found the same thing in bile, it has been named urobilin. Besides the hitherto mentioned organic and inorganic normal constituents of urine, there are the pathological and so-called accidental ones. The former are : albumen, sugar, biliary mat- * Bericlit der deutschen chem. Gesellschaf t, Band 2, p. 12. Chem. Central- blatt, 1869, p. 13. f Zeitschrift fur analyt. Chem. , Band 3, p. 246, und Band 9, p. 150. Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, 0RG4NIG. \\ ters, fat, mucin, leucin, tyrosin, and several others whicli are met with in the urine in certain disturbances of the health, while the latter, the accidental, may be of very different sorts, according as one or the other body is accidentally or intention- ally introduced into the economy, and is removed with this fluid, either unchanged or after previous chemical decomposition. We will now consider more particularly the different normal constituents, organic and inorganic, as well as the pathological and accidental ones. n. NOEMAL CONSTITUENTS OP URINE. A. Organic. § 2. Ueea. Formula: OH.N^a Carbon 20-00 Hydrogen 6 •6'? Nitrogen 46-67 L Oxygen 26-66 100-00 A. Presemx. Urea is found in the urine of mammalia, birds, and reptiles; it is most abundant in that of the carnivora. But, besides in the urine, we find it constantly in the blood, where it often is very considerably increased, especially in kid- ney diseases (Bright's disease), or after extirpation of the kidneys. This last circumstance indicates that urea is not formed in the kidneys, but in the blood, by an oxidation of nitrogenous matters which have become useless, fragments of tissue or superfluous nitrogenous bodies in the blood. In the muscular juice of men and sucking beasts, urea has hitherto not been detected, though other bodies have been found, as kreatin, xanthin, sarkin, etc., from which urea can be produced artificially. Whether the above bodies, among which also belongs the uric acid normally found in the blood, are the precursors of urea, and after further decomposition are excreted partly as urea, is not yet perfectly proved ; at least it appears from Voit's experiments * that the kreatin of muscle takes no * Zeitsctrift far Biologie, Band 4, p. 77, etc. Digitized by Microsoft® 12 AlfALTSIS OF THE UBINE. part in tlie formation of urea, and also the experiments of Ssubotin, according to whom urea is formed from kreatin under the influence of the renal tissue, have not been confirmed.* On the other hand, it is an established fact that, after the intro- duction of uric acid, guanin, allantoin, thein, gluten, glycocoU, and leucin, also after partaking of food rich in nitrogen, an increase in the urea can readily be determined.t Moreover, the experiments of von Knieriem % showed that chloride of ammonium, asparagin, and asparagic acid increase the urea in urine, a fact which is the more interesting in that asparagic acid has been detected by Eadziejewski and E. Sal- kowski§ among the products of the digestion of fibrine by means of pancreatic ferment. Besides in the urine, urea is found normally in the blood,|| bile, and liver, in the amniotic fluid, in the vitreous and aqueous humors, and finally, Funke and others have found it in the sweat. Wurtz found it in the lymph and chyle of several ani- mals ; Lefort, in the milk of healthy cows. Urea appears to be wanting normally in the muscle of human beings and of most vertebrates. At least it has not been possible, thus far, to detect it in this tissue. It is probable, however, that urea occurs in the muscles and organs of many animals where it has hitherto not been found in mankind. Stadeler and Trerichs found considerable quantities of urea in the muscle and in almost all of the organs of many cartilaginous fishes (plagio- stomes), while they sought in vain for it in corresponding parts of the body of bony fishes. If the separation of urea by the kidneys is more or less im- peded, or even entirely suspended, we see it appear in almost all of the animal fluids. It first seems to be increased in the blood, and readily passes thence into the serous exudations ; under these circumstances urea has been found in the juice of muscle, in saliva, in the vomitus, and even in pus and milk. The sweat is then especially rich in urea, so that after its evap- oration a slight crust of urea remains. * E. Qsclieidleii's Habilitationssclirift, Leipzig, 1871. \ BericM der deutsch. chem. Qesellscliaft, 1869, p. 566. X Zeitschrift fiir Biologie, Band 10, p. 363. § Berliner Berictte, Band 7, p. 1050. 11 Annal. der Cliem, Pharm., Band 156, p. 88. Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, ORGANIC. 13 After the artificial introduction of urea into tlie body under normal circumstances it is not decomposed, but the economy frees itself very quickly from it, so that we may often, within a few minutes, detect a considerable increase of the urea in the urine. Gallois saw a rabbit weighing two kilograms die, after being given twenty grams of urea. First there occurred an in- crease of the respiration, then followed weakness of the limbs, trembling, general convulsions, tonic spasms, and finally death. The urine of a healthy individual contains, on an average, with a mixed diet, 2*5 to 3"2 per cent, of urea, so that within twenty-four hours between 22 and 35 grams are eliminated. The amount of urea excreted, however, is very variable, and depends very much on the weight of the body and on the food. Thus, Lehmann with a purely animal diet saw the twenty-four hours' amount of urea increase to 58 grams ; on a diet poor in nitrogen, on the contrary, it fell to less than fifteen grams, but with entire deprivation of food the urea did not ever wholly disappear. The artificial formation of urea can be brought about in very different ways. For example, cyanate of ammonium, which has the same elementary composition as urea, becomes urea imme- diately upon heating its solution. It can, moreover, be pro- duced from kreatin, guanin, allantoin, alloxan, oxamide, and many other bodies. Uric acid, by the action of strongly oxidiz- ing substances, produces as final products only urea, carbonic acid, and water. Nathansen obtained urea by heating carbonic ether with an excess of ammonia, and also by the action of chloro-carbonic oxide gas on dry ammonia gas. I can confirm both of these methods of formation. According to Basaroff it is also formed by prolonged heating of dry carbamate of ammo- nium, and also ordinary sesquicarbonate of ammonium, in sealed tubes, to 130° or 140° C. B. Preparation. 1. From Urine. Two volumes of urine are treated with one volume of baryta solution, such as is used for the quantitative estimation of urea, the precipitate of phosphate and sulphate of barium is filtered off, and the filtrate evaporated to dryness on a water bath. The residue is extracted with alcohol, after filtering is again evaporated to dryness, and the mass which now remains is treated with absolute alcohol. The solution Digitized by Microsoft® 14 ANALYSIS OF THE UBINE. contains pure urea which after evaporation crystallizes in the form of colorless needles. Should the urea thus obtained not be perfectly colorless, it can be made so by treating it with a little pure animal charcoal. For the isolation at the same time of kreatinin, xanthin, and urea from one and the same specimen of urine, see below under Xanthin, § 5. 2. From Cyanate of Ammonium. 80 grams of dried ferro- cyanide of potassium are melted by gentle heat with 30 of car- bonate of potassium, until a specimen removed solidifies to a milk-white glass. When this point is reached, the crucible is removed from the fire, and 150 grams of red oxide of lead are gradually added in small portions ; it is then heated about ten minutes, with frequent stirring, and the mass is poured on to an iron plate. After cooling, the raw cyanate of potassium is dis- solved in a solution of 80 grams of sulphate of ammonium in 4 or 500 of water, filtered when all is dissolved, and the filtrate evaporated to dryness. The dried mass is extracted with small portions of alcohol (1-200 grams, 90 per cent.), boiled several times, filtered, the alcohol distilled off again, and the mass allowed to crystallize. J. Williams recommends using commercial cyanide of potas- sium instead of the ferrocyanide. He extracts the fused mass oxidized by red oxide of lead with cold water ; after powdering it, frees the filtrate from the carbonates by the addition of nitrate of barium, and thus precipitates from the clear solution pure cyanate of lead by the addition of nitrate of lead, and de- composes the former, after washing and drying it, by digesting while hot with the equivalent amount of sulphate of ammonium, dissolved in the necessary amount of water. C. Microscopic Properties. If pure urea is crystallized Quickly from a concentrated solution, it appears under the microscope in the form of white, silky, lustrous needles. If, however, we allow the crystallization to take place slowly from dilute solu- tions, it forms white, almost transparent, beautifully lustrous, striated, four-sided prisms, whose ends are terminated by one or two oblique surfaces. (Funke, Taf. II., fig. 4; 2'° Aufl. Ill, 1.) These crystals belong to the rhombic system. D. Chemical Properties. Urea has a bitter, cooling taste, simi- lar to that of saltpetre. Its crystals contain no water of crys- Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE. ORGANIC. 15 tallization, are permanent in the air, and readily dissolve in water and alcohol. The solutions are neutral. It is almost insoluble in ether. 1. Urea heated moderately on platinum foil melts with the evolution of ammonia; on beiiig heated somewhat more it solidifies again, becomes brown, and finally burns readily and completely without leaving a residue of carbon. 2. Urea heated with concentrated mineral acids, as sulphuric acid, etc., or with caustic potash or soda, undergoes decomposi- tion. One molecule of water is absorbed, and carbonic anhy- dride and ammonia are produced. (Quantitative estimation by the. method of Eagsky and Heintz.) It undergoes this decom- position also when nitrogenous organic matters capable of decomposition (cause of the alkaline fermentation of urine) are added to its solution ; and second, when heated for a long time in a sealed tube with caustic baryta to a higher tem- perature than 100°. (Quantitative determination by Bunsen's method.) €H4N,0 + H,a = CO, + 2NH3. 3. If nitrous acid or a solution of mercurous nitrite in nitric acid be added to a solution of urea, it decomposes into water, carbonic anhydride, nitrogen, and ammonia. (Liebig, Wuhler, Ludwig, and Krohmeyer.) ©114^,0 + NHa,+NHa3=C02 + 2K" + JSTHjjJSTOs + HjO. 1 gram of urea furnishes, therefore, 1"2 grams of escaping gas. According to the investigations of A. Olaus,* the reaction takes place in the above-mentioned way only when the neces- sary amount of nitrous acid is added to the urea in the cold and then heated ; and second, when at the same time with the nitrous acid an equivalent amount of a stronger acid is added. In the last case it is immaterial whether heat is applied at first or later ; also the addition of an excess of nitrous acid is not im- portant. 4. If a solution of urea is warmed with nitrate of silver, an insoluble precipitate of cyanate of silver is formed, and the solution contains nitrate of ammonium. In this way it can be converted into the same form of combination (cyanic acid and ammonia), from which it can be produced artificially. 5. Mercuric oxide forms several stable compounds with urea, * Zeitsclirift fiir analyt. Cliemie, Band 10, p. 336. Digitized by Microsoft® 16 ANALTSia OF THE UBINE. in which, according to circumstances, two, three, or four equiva- lents of mercuric oxide combine with one equivalent of urea. 6. A solution of mercuric nitrate produces in a solution of urea a white flocculent precipitate, which, according to the con- centration of the fluid, has a variable composition. The pre- cipitate contains to one equivalent of nitrate of urea, two, three, or four equivalents of mercuric oxide. Corrosive sublimate, on the contrary, in a feebly acid solution of urea, gives no precipitate, but it does in an alkaline solution. On this the quantitative estimation of urea and chlorine by Liebig's method depends. 7. Urea treated with a solution of hypobromite or hypo- chlorite of sodium decomposes into nitrogen, carbonic acid, and water. The carbonic acid is rapidly absorbed by the lye, so that the urea can be determined quantitatively by direct meas- urement of the nitrogen.* eH,KO + 3]SraCia = 3NaCl + Ca2 + 2H,a +3]Sr. This method, on account of its rapidity, is to be highly recommended for clinical purposes. 8. Urea in alkaline solution at ordinary temperature resists the oxidizing influence of permanganate of potassium very ener- getically; in a hydrochloric acid solution, however, it decom- poses with great readiness on being heated into carbonic acid and ammonia. By this behavior urea appears to be the last end product of the retrograde metamorphosis, since in alkaline solu- tion, as in normal blood, it cannot be further oxidized by ox- idizing agents, and is thus essentially distinguished from uric acid, kreatin, guanin, etc., which stand on a somewhat higher step. Urea comports itself quite as indifferently with ozone, while uric acid decomposes very energetically with the produc- tion of urea. But in the presence of alkalies urea is decom- posed by ozone into carbonic acid and ammonia.t 9. Urea forms with many salts (corrosive sublimate, chloride of sodium, nitrate of calcium, chloride of calcium, etc.) crys- tallizable compounds; it also forms with many acids, organic (succinic, tartaric, citric, and gallic acids) as well as inorganic, crystallizable salts, of which three, the nitrate, phosphate, and oxalate, are especially important. * Davy, Leconte, Hiifner. Journ. fiir prak. Chemie, 1871, p. 1. t Compare also Chapman and Smith in the Chem. Centralblatt^ 1868, No. 308. Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, OBQANIG. 17 a. Nitrate of Urea. GK,'N,(^,'N'H.Qs-—{G2'SlJ^20„'NO,'RO). If tol- erably concentrated pure nitric acid, free from nitrous acid, is added to a concentrated solution of urea, this compound sepa- rates, after tlie mixture becomes cool, in white shining plates or scales, which are mostly single, but often in superimposed masses. If only a small amount of urea is present, the compound is allowed to form under the microscope, best in the following way : The end of a little piece of thread is laid in the drop of fluid to be tested for urea, a covering glass is placed over the , drop and one-half of the thread, while the other end of the thread is moistened with a drop of pure nitric acid. The two fluids gradually mingle, and the crystals form under the cover- ing glass on both sides of the thread with great regularity. If the crystals are watched during their formation we find, first, together with many complicated forms, rhombic tables or short prisms, whose acute angle measures 82°. The forms are changed by modification of the obtuse angle by faces into hexagonal tables or six-sided prisms. Such a regular development, how- ever, only occurs during slow crystallization, while, when the crystals form rapidly, a large number of six-sided tables overlap each other like tiles on a roof. Frequently, also, obtuse rhom- bic octahedra of little durability form at the first meeting of the two fluids, their acute angle measures 82°, but a greater num- ber of particles always accumulate on these, so that the primi- tive octahedra are changed into the above-named rhombic or hexagonal tables. Finally, very characteristic twin crystals are observed which, with mutually oblique end-surfaces, are formed by the turning of one crystal 180°, corresponding to the well- known forms of gypsum. (Plate II., fig- 6.) This salt, which is permanent in the air, is readily soluble in water, more difficultly soluble in water containing nitric acid, and most difficultly soluble in alcohol containing nitric acid. Heated quickly on platinum foil it deflagrates, but at 140° decomposes into carbonic acid, nitrous oxide, urea, and nitrate of ammonium. On mixing a concentrated solution of nitrate of urea with oxalic acid, the second compound oxalate of urea is precipi- tated. b. Oxalate of Urea. (€H,N,0)„€,HA+HA— [(CAN.O,), 2 Digitized by Microsoft® 1Q ANALYSIS OF Till! URINE. CjHnOa + 3HO.J This compound also forms on mixing oxalic acid with a concentrated solution of urea; it is precipitated in long, thin laminae or in prisms. If the formation is allowed to take place under the microscope, it usually appears similar to that of nitrate of urea in hexagonal tables ; at times, how- ever, also in forms of four-sided prisms. (Funke, Taf. II., fig. 6; 2" Aufl., III., 3.) This compound is readily soluble in water, but is precipitated again from the solution by an excess of oxalic acid. On be- ing heated it decomposes into carbonate of ammonium and cyanuric acid. c. Phosphate of Urea, €H,N,a,PH30 -[0,H4N,0,3HO,POJ, was obtained by Lehmann from the evaporated urine of pigs fed on bran, but it can also be artificially produced in large glisten- ing crystals, belonging to the rhombic system, by phosphoric acid and urea. The crystals are very easily soluble in water, and do not decompose in the air. E. Detection. In order to detect urea in the urine it is suffi- cient, in most cases, to evaporate a small quantity, 15 to 20 grams, to a syrupy consistence on a water bath, and to treat the residue repeatedly with alcohol until a drop evaporated on a watch glass does not leave any residue. The urea is contained in the alcoholic solution, and remains behind more or less colored after the alcohol is expelled by evaporation on a water bath. Dissolved in a little water, and a part treated with pure nitric acid, and a part with a concentrated solution of oxalic acid, it furnishes the two above-named compounds. If very small quantities are allowed to crystallize with nitric acid under the microscope, the crystalline forms mentioned above, under nitrate of urea, will be seen to form. If, however, the urine contains albumen, the above portion is treated with a drop of acetic acid, heated to boiling, so that the albumen is entirely coagulated, filtered, and the filtrate treated as before, first evaporated on the water bath, then the residue extracted with alcohol, etc. Digitized by Microsoft® IfOBMAL G0NSTITUBNT8 OF UBINE, ORGANIC. 19 § 3. Keeatinik. Formula: €4H,N30 [CeH,N30,] r Carbon 42-48 Hj'drogen 6 '19 Nitrogen 37-17 L Oxygen 14-16 100-00 A. Presence. Kreatinin, by all means the strongest base of the animal body, was first discovered by Liebig in the crystalline precipitate which Heintz, and later Pettenkofer, obtained from concentrated urine with a solution of chloride of zinc. Liebig found in this chloride of zinc compound, kreatinin together with kreatin, and therefore arrived at the conclusion that both bodies were originally contained in the urine. But Heintz furnished proof later, by a very thorough investigation, that no kreatin is contained in fresh urine, but that it is formed by the decomposition of the chloride of zinc compound of kreatinin by the absorption of water by the kreatinin, a fact which has now been confirmed by Liebig and Dessaignes. Since kreatin can readily be changed into kreatinin by withdrawing water, the kreatin, which is always to be found in the juice of muscles, be- comes in the blood, or, according to Voit, more probably in the kidneys, kreatinin through loss of water, and is then discharged in this form with the urine. Dessaignes, on the contrary, thinks that the fluid of muscle, like the urine, originally contains only kreatinin which first becomes kreatin by the separation of water caused by the long-continued action of warmth in the neutral fluid. But according to my investigations the matter is just the opposite. By the method described under kreatin this body can be obtained pure in a very short time from the juice of muscles ; and I have also proved with certainty that kreatin, by long heating in a watery solution, gradually be- comes converted into kreatinin. In the juice of muscles there is no kreatinin, but only kreatin, and when the former is found it has been formed from kreatin by the too long action of heat. According to my own determinations there are from 0-6 to 1-3 grams of kreatinin eliminated by a healthy man on good mixed diet in an average amount of 1,500 to 1,600 cubic centimeters Digitized by Microsoft® 20 ANALYSIS OF TEE UBINR of urine in the twenty-four hours. Munk found an increased excretion of kreatinin in acute diseases, especially in pneumo- nia, typhoid fever at the height of the disease, intermittent fever, etc. A diminution occurred during convalescence from acute diseases, especially when the patients were very anaemic. Hofmann* found in his extended observations on himself a daily excretion of kreatinin of from 0-52 to O'Sl grm., the average was 0-681 grm. ; in others, on the contrary, the average was 0-99 grm. The urine of sucklings was found free from kreatinin ; it appeared first after partaking of meat. Boys ten to twelve years old passed a daily average of 0"387 grm. ; a person seventy years old, on the contrary, 0'517 to 0-593 grm. In women somewhat less kreatinin, on an average, was found than in men, the average of seven estimations was 0-65 grm. Physical exercise appeared to be without influence ; meat diet considerably increased the amount of kreatinin in the urine, even in young children. Hofmann found a diminution of the excretion of kreatinin in cases of debility, deficient nutrition, and in diabetes. In advanced degeneration of the kidneys, in spite of an abundant meat diet, the excretion is diminished, which confirms the opinion of Voit t that the transformation of muscle kreatin does not take place in the blood first, but in the kidneys, where the acid urine is separated from the alkaline blood. Besides in human urine Yerdeil and Marcet found it in the blood, Socoloff in the urine of the horse and sucking calves, Dessaignes in the urine of the cow, and Liebig in the urine of the dog. According to Scherer it appears to be found also in the amniotic fluid. Voit obtained kreatin from the blood of calves, oxen, and sheep, but no kreatinin. B. 3ficroscopic Proper-ties. Krfeatinin appears in the form of colorless, very glistening prisms, which belong to the monoclinic system. (Funke, Taf. III., fig. 2 ; 2" Aufl., VI., 5.) C. Chemical Properties. Kreatinin is probably the strongest organic base of the animal kingdom ; it has almost as caustic a taste as ammonia, and is soluble in eleven parts of water at 12° to 20° ; it is more easily soluble in hot water. One hundred *Virchow's Archiv, Baud 48, p. 358. f Zeitsohrift fur Biologie, Band 4, p. 114. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. 21 parts of cold alcohol dissolve about one part of kreatinin ; in hot alcohol it is soluble in such amount, that it separates again on cooling in white crystalline masses ; ether takes up only a very small quantity. The solutions have a strongly alkaline reaction and caustic taste, like dilute ammonia. Kreatinin comports itself like a nitrile base ; it directly com- bines with ethyl iodide, forming kreatinin ethyl iodide, from which ethylkreatinin is separated as a strong base by oxide of silver, and appears in a crystalline form. 1. If a concentrated solution of chloride of zinc is added to a solution of kreatinin, a crystalline precipitate of kreatinin chloride of zinc immediately forms {QJl.^iQ),7in.G\ — [CsHiNjOj, ZnCl]. The crystals are distinctly prismatic when formed very slowly ; on more rapid formation, however, only fine needles are seen under the microscope, which, grouped concentrically, either form complete rosettes or tufts, which cross each other, or of which two are so laid together with a short pedicle that they resemble pencils running into each other. Kreatinin chloride of zinc is difficultly soluble in cold water, more readily in hot water, but insoluble in alcohol. If kreatinin is separated from an aqueous extract of urine by chloride of zinc, the compound is obtained chiefly in the form of dark warty masses, in which, even under the microscope, a crystalline structure can scarcely ~be recognized. At times even here, distinct crystals in the form of a rosette, fine nee- dles, are obtained, which are united into broom and star-shaped masses. Kreatinin chloride of zinc is obtained from an alco- holic extract of urine by precipitating with an alcoholic solu- tion of chloride of zinc, always as a faint yellow powder, which under the microscope shows almost exclusively yellow, trans- parent, sharply defined spheres of different size, in which, with a high power (400), a striation may be distinctly seen. By dissolving this powder in hot water, regular forms can readily be obtained under the microscope. When the solution has completely cooled, a drop is placed on an object glass, and a little solution of chloride of zinc is added with the aid of a small piece of thread, just as was described under nitrate of urea, page 17. Very soon the above-described characteristic rosettes of crystals, often of considerable size, are seen to form on both sides of the thread. Digitized by Microsoft® 22 ANALYSIS OF THE URINE. 2. A not too dilute solution of kreatinin treated with a con- centrated solution of nitrate of silver, solidifies to a network of crystalline needles, which dissolve in boiling water, but sepa- rate again on cooling. 3. Mercuric chloride acts in a similar way. The precipitate is at first caseous, but changes in a few minutes to a mass of fine colorless needles. 4. A solution of mercuric nitrate does not cause a precipi- tate immediately in dilute solutions of kreatinin, but if a solu- tion of carbonate of sodium is added to the mixture drop by drop till the turbidity remains permanent, the compound crys- tallizes in beautiful microscopic crystals. In concentrated solutions the precipitate forms very quickly, and if no free nitric acid is present, without the addition of sodic car- bonate. 5. If an ammonium salt is heated with kreatinin, ammonia is evolved. 6. Kreatinin gives with hydrochloric, nitric, and sulphuric acids, good crystallizable compounds, soluble in water : a. Chloride of kreatinin crystallizes in transparent prisms and broad leaves. With chloride of platinum it gives a com- pound similar to those formed with potassium and ammonium chlorides, which is easily soluble, and crystallizes in aurora- colored prisms. b. Sulphate of kreatinin forms concentrically grouped, trans- parent, quadrilateral tables. It is to be emphatically remarked that kreatinin chloride of zinc, the most important compound of kreatinin, is not precipi- tated from chloride of kreatinin, etc., by the addition of a chloride of zinc solution. The separation follows immediately, however, if before the addition of the chloride of zinc solution, acetate of sodium in sufficient amount is added to the krea- tinin salt. 7. By the action of mercuric oxide, lead peroxide, and sul- phuric acid, or permanganate of potassium, kreatinin, like krea- tin, is decomposed into oxalic acid and oxalate of methyluramin G,H,X30+a + H,a = G.H,N3+e,HA-[C,H,N30, + 40=C,H,N3 + 0A]. 8. Kreatinin is formed from kreatin by the action of the mineral acids, or by the prolonged heating of an aqueous Digitized by Microsoft® irOBMAL GONSTITUBNTS OF UBINE, OBOANIG. 23 solution to 100° C, wMle the latter loses two molecules of water. If a solution of kreatinin is allowed to stand a long time in contact with alkalies, it becomes kreatin again by ab- sorbing water. Warmth favors the transformation. (Liebig, Dessaignes.) 9. On heating with caustic baryta in an aqueous solution, kreatinin furnishes methylhydantoin with disengagement of ammonia. At the same time a syrupy acid is formed which has not been closely examined. (Kreatinin) (Methylhydantoin) [C3H,N30, + H,0,= C,H,N A + NH3] . When similarly treated, kreatin forms methylhydantoin to- gether with sarkosin and urea. (See Kreatin.) « Methylhydantoin is formed artificially by melting together sarkosin and urea. (Huppert.)* 10. Phosphomolybdic acid gives in aqueous solutions of pure kreatinin acidulated with dilute nitric acid a yellow crystalline precipitate, which forms immediately when diluted one thou- sand times, but only after prolonged standing when diluted from five to ten thousand times. In a great excess of hot nitric acid the compound dissolves, but on cooling it separates in beauti- ful very characteristic crystals, whose microscopic appearances are not without value in the detection and recognition of krea- tinin. (Kerner.)' D. Preparation of Chloride of Kreatinin from Urine. Eight to ten liters of urine are evaporated to a third or quarter, and separated after cooling from the precipitated salts. The mother liquor is precipitated with a solution of sugar of lead, the excess of oxide of lead is ren^oved by sulphuretted hydrogen, and a concentrated solution of corrosive sublimate is added to the filtrate, which is nearly neutralized with sodic hydrate. The precipitate, principally a compound of kreatinin with mercuric chloride, is suspended in water and decomposed with sulphu- retted hydrogen, the filtrate decolorized with animal charcoal and evaporated to crystallization. By repeated crystallization *Bericht. der deutschen chem. Gesellschaft, Band 6, p. 1378. Digitized by Microsoft® 24 ANALT8I8 OF THE UBINE. from strong alcohol, white crystalline crusts are finally obtained, or large, hard, shining prisms of chloride of kreatinin. The re- moval of hydrochloric acid is accomplished by plumbic hydrate, as is shown below. (Maly.) E. Detection. Since kreatinin occurs only in small amount in the urine, large quantities are necessary for its certain recogni- tion, yet 2 to 300 cubic centimeters are sufficient for its qualita- tive detection in most cases. The process is as follows : The fresh urine is neutralized with milk of lime and the phosphoric acid precipitated by a solution of chloride of calcium. The precipi- tate is filtered off, and the filtrate evaporated rapidly on a water bath to a thick syrup. The residue thus obtained is extracted with strong alcohol, best with absolute alcohol, allowed to stand a few hours, filtered, and the clear fluid treated with a concen- trated solution of chloride of zinc free from acid. After violent agitaflion a turbidity will soon appear, and after forty-eight hours the separation of the kreatinin chloride of zinc is com- plete. The compound is washed on a filter with alcohol, dried, and, according to C. 1, subjected to a microscopic examination. If we wish to produce pure kreatinin, the compound which has been obtained is dissolved in a little hot water, and oxide of zinc and hydrochloric acid separated by freshly precipitated thoroughly washed plumbic hydrate, with which the fluid is to be boiled at least a quarter of an hour. The fluid obtained by filtration is decolorized by boiling with animal charcoal, and is then evaporated to dryness. The residue, which is always a mixture of kreatinin and kreatin, is treated with cold strong alcohol, by which the kreatinin is removed while the kreatin remains behind. By evaporation of the alcoholic solution kreatinin is obtained in pure crystals, while the kreatin is obtained readily in pure form by re crystallization from a little hot water of the residue insoluble in alcohol. It is to be observed that, when the solution of kreatinin chloride of zinc has been treated for a long time with oxide of lead, often only kreatin and no kreatinin at all is found in the residue. The latter becomes converted into kreatin by the prolonged action of the excess of oxide of lead by absorbing two molecules of water. If the urine contains albumen, it must first be separated by coagulation. In diabetic urine it is best, according to Gaeht- Digitized by Microsoft® > NORMAL CONSTITUENTS OF URINE, ORGANIC. 25 gens,* to first destroy the sugar present by fermentation with yeast. Kreatinin thus obtained is characterized by its strong basic qualities, by its tendency to form double compounds with the metallic salts, and salts with acids, as well as by its characteris- tic behavior with phosphomolybdic acid. It is distinguished from kreatin further by its much greater solubility in strong alcohol, as well as by its form of crystallization. Kreatin is not so well characterized ; there is nothing better for its certain recognition than a comparison with the pure crystalline substance. The alcoholic extract of urine, from which, after acidifying with hydrochloric acid, hippuric acid has been separated by shaking with ether, § 8, E. 2, is best used for the detection of kreatinin. After the ether is removed, the hydrochloric acid is accurately neutralized with sodium hydrate, diluted with thirty to forty cubic centimeters of absolute alcohol, and the kreatinin precipitated by the chloride of zinc solution. According to Kerner, kreatinin may easily be detected by the following method : The urine is precipitated with a concen- centrated solution of mercurous nitrate, filtered, treated with sulphuretted hydrogen which is separated from the filtrate by warming and the addition of a drop of nitric acid, and while it is still warm is treated with phosphomolybdic acid. After cooling and standing a short time the phosphomolybdate of kreatinin separates in characteristic crystals, especially on the walls of the vessel, where they have been rubbed with a glass rod. (See above under 0. 10.) §4. Keeate Formula : €4H9]Sr3a2+H5a [O^H^NaO.+SHO] ' Carbon Hydrogen Nitrogen . Oxygen 36-64 6-87 32-06 34-43 (Anhydrous.) 100-00 A. Presence. Kreatin is found in the juice of striated, and also of smooth muscular fibre, acc6rding to my investigations, * Zeitschrif t fur analyt. Chem., Band 8, p. 100. Digitized by Microsoft® 26 ANALT8IS OF TUB UBINE. on an average of 0*2 per cent. It has, moreover, been found in greater or less quantity in the various transudations, in the blood, the brain, the kidneys, and the amniotic fluid. (See re- marks under kreatinin concerning its presence in the urine.) Not much can be said definitely about the physiological sig- nificance of kreatin. If we regard only its occurrence in the juice of muscle as well as its considerable richness in nitrogen, we would be inclined to regard kreatin as an important nutritive material ; but the ready decomposition of this body into urea, kreatinin, and sarkosin, which are without doubt to be regarded as excretive materials, stamp it rather as an excretive material, which stands on the ladder of retrograde metamorphosis as a middle step between those substances of the most complex (protein substances) and those of the simplest molecular com- position (urea, etc.). At all events, kreatin stands nearer to urea than to the protein substances. B. Preparation. Fresh, finely-chopped beef is thoroughly mixed with an equal amount of water, and the mass heated ten or fifteen minutes on a water bath with constant stirring to 55°-60° C, so that the albumen just commences to coagulate. It should then be strained through cloth, the residue squeezed out, and the fluid thus obtained heated to boiling to completely coagulate the albumen. After cooling it is filtered, and the filtrate treated with basic acetate of lead in slight excess. The lead precipitate is collected on a filter, washed, and the excess of lead precipitated from the entire filtrate by sulphuretted hydrogen. After filtration from the sulphide of lead, a color- less filtrate is obtained, from which, after sufficient concentra- tion on the water bath, colorless kreatin crystallizes out after standing awhile. The crystals are to be collected on a filter, washed with alcohol, and dried in the air. After one recrystal- lization they are obtained absolutely pure. Kreatin may be obtained artificially, by warming an alcoholic solution of sarkosin and freshly prepared cyanamid for several hours to 100° C. on the water bath.* For its preparation from urine, see kreatinin under " Detec- tion." C. Microscopic Properties. Kreatin, when pure, forms colorless, * Volhard, Chem. Centralblatt, 1869, p. 364. Digitized by Microsoft® NOBMAL CONSTITUENTS OF URINE, OBGANIO. 27 perfectly transparent, strongly refractive prisms wliicli belong to the monoclinic system. (Funke, Taf. III., fig. 1 ; 2" Aufl., Taf. IV., fig. 4.) In most cases it forms groups whose appear- ance reminds one of that of sugar of lead. If a dilute solution of kreatin is placed in a concave polished object glass and allowed to evaporate spontaneously, at first on the edge, a collection of long prismatic crystals is observed which are thick at their free ends and gradually become nar- rower. In the middle of the fluid regular crystals gradually form, principally prisms, which are often united by their acute angles in a fan shape. Single crystals have, in the middle, a characteristic bulging like those of lactate of zinc, narrowing toward the ends, and are terminated by two surfaces. Finally also, thick, apparently rectangular, tables, at times single, at times in large numbers, frequently appear. D. Chemical Properties. Kreatin has a bitter, harsh taste, dis- solves in seventy-five parts of cold water, and much more readily in hot water ; the kreatin separates from the solution again on cooling, as crystals, in the form of fine shining needles. It is with difficulty soluble in alcohol, one part requiring nine thou- sand four hundred and ten parts ; while ether does not dissolve any. 1. The aqueous solution is without reaction on vegetable coloring matters, has a bitter taste, and very readily decom- poses. If a dilute solution of kreatin is evaporated slowly on the water bath, it gradually becomes converted into kreatinin. Dessaignes has recently succeeded in producing crystallizable salts of kreatin with sulphuric, hydrochloric, and nitric acids. 2. If kreatin is boiled a long time with caustic baryta it de- composes into urea, sarkosin, and methylhydantoin. [08H,N304 + 3H0 = C^H^N^O, + CeH,]SI OJ (Kreatin) (Urea) (Sarkosin). e^H^NaO,-- ]srH3= e4HsN.o, [C8H,N304-NH3=C8HeN,04] (Kreatin) (Metliylhydantoin). If the action continues too long, the urea splits up into car- bonic acid and ammonia ; the latter escapes while the carbonic acid combines with the barium. Sarkosin can be obtained in Digitized by Microsoft® 28 ANALYSIS OF THE URINE. colorless crystals, though with difficulty ; methylhydantoin crys- tallizes more easily, and can be separated from the sulphate of sarkosin by treating with alcohol. 3. Dilute mineral acids dissolve kreatin without decomposi- tion, but boiled with concentrated acids it changes into kreatinin by giving up water. [CsH,N30,-2HO=C3H,N302] (Kreatin) (Kreatinin). 4. Pure kreatin in dilute solution is not precipitated by chlo- ride of zinc. From a concentrated solution kreatin chloride of zinc crystallizes in hard crystals. Similar compounds are fur- nished by kreatin with chloride of cadmium, chloride of copper, and mercuric nitrate. 5. Peroxide of lead has no action on kreatin; it is, on the contrary, decomposed by permanganate of potassium ; the de- composition products which are formed, with the exception of carbonic acid, are unknown. Perhaps urea is one of them. 6. A solution of kreatin, boiled with an excess of mercuric oxide, causes metallic mercury to be separated with evolution of carbonic anhydride, and the solution contains the oxalate of another powerful base, methyluramin (€2H,]Sr3). (See § 3, 0. 7.) E. Detection. See Kreatinin. § 5. Xanthin. w 'Carbon 39-5 Formula : ©34^" A j Hydrogen 2-6 [CioH4]Sr404] I Nitrogen 36-8 .Oxygen 31-1 100-0 A. Presence. Xanthin was recognized by Scherer and Stadeler as a substance very widely distributed in the animal economy, while, until within a short time, it was known only as a very rare constituent of some vesical calculi. Scherer found xanthin in human urine, in the spleen, pancreas, brain, liver of the ox, in the thymus gland of the calf, and in the muscular tissue of the horse, ox, and fish, also in the spleen in cases of splenic tumor, Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, ORGANIC. 29 as well as in the liver in acute yellow atrophy. Hosier * found xanthin in the blood and urine in leuksemia. Diirr and Stro- meyer found it in the urine after the use of sulphur baths. Bence Jones observed it once in a ten-year-old child as a uri- nary sediment. Xanthin was mostly accompanied by hypoxan- thin; but in the spleen, liver, and brain by uric acid also. Salkowsky t proved the presence together with xanthin of a hypoxanthin-like body in very small amount in normal as well as in leuksemic urine. B. Microscopic Properties. Xanthin is amorphous, and shows under the microscope no crystalline structure. A hot aqueous solution of xanthin deposits it on cooling, mostly in the form of colorless flocculi, at times, also, as a fine powder, which under the microscope appears to consist of round bodies which, when in the flocculent form, are arranged in rows, and in the powdered lie singly. C. Chemical Properties. Xanthin forms hard, white pieces, which on rubbing with the nail assume a waxy lustre. It is difficultly soluble in cold water, and somewhat more soluble in boiling water. It has been produced artificially from guanin. 1. Ammonic and potassic hydrates, hydrochloric, nitric, and sulphuric acids dissolve xanthin. It is precipitated from its alkaline solutions by the addition of an acid, while it gives crys- talline compounds with the acids. 2. The cold saturated aqueous solution gives with corrosive sublimate a white precipitate ; when diluted thirty thousand times an evident cloudiness occurs, but when diluted forty thousand times it is not perceptible ; with cupric acetate yellow- ish-green flocculi separate on boiling. The solution in ammo- nia is precipitated by chloride of cadmium and chloride of zinc, also by plumbic acetate ; the latter precipitate often changes, on standing, into shining scales. 3. Nitrate of silver causes in a nitric acid solution of xanthin a flocculent precipitate, which dissolves on heating and slowly separates again on cooling. Under the microscope the silver com- pound shows after rapid cooling hairlike, crystalline needles, but on slow cooling wavy aggregations of fine crystals are formed. * Hosier declares he found sarkin (hypoxanthin),. but the reactions described by him correspond rather to those of xanthin than sarkin. \ Virchow's Archiv, Band 50. Digitized by Microsoft® 30 ANALYSIS OF TKM URINE. In an ammoniacal solution of xantliin, nitrate of silver gives a gelatinous precipitate insoluble in ammonia. CsHiN^Os + AgjO. -[0,oH,N,0, + 3AgO]. 4. Xantliin dissolves in nitric acid on heating witliout evolu- tion of gas, and a yellow residue remains after evaporating the solution, which residue does not become purple by the action of ammonia, but becomes yellowish red by adding potassic hy- drate, and when heated beautiful violet red. If uric acid is mixed with xanthin, as is the case in certain calculi which contain it, the above reaction is modified by the murexid reaction which takes place at the same time. This is the reason, according to Lebon,* why xanthin has been so sel- dom found in calculi. To separate the two the powdered cal- culus is to be treated with hydrochloric acid and heated. Since uric acid is insoluble in hydrochloric acid, the filtrate contains only chloride of xanthin, which can be obtained by evaporation and used for the above reaction. 5. If xanthin is dissolved in strong hot hydrochloric acid beautiful microscopic crystals of chloride of xanthin separate on slow cooling in the form of six-sixed tables, lying together in groups and rosettes. Very frequently, however, only spherical and oval forms can be seen. The nitric acid salt crystallizes in a similar form though not so characteristic ; here also rosettes are seen to form from rhombic tables and prisms. 6. If calcic hypochlorite is mixed in a watch glass with sodic hydrate, and a little xanthin added, a dark green border first forms around the granule and soon becomes brown and finally disappears. (Hoppe-Seyler.) 7. Phosphomolybdic acid produces, even in very dilute solu- tions of xanthin, a copious yellow precipitate. In hot dilute ni- tric acid this compound is soluble, but it separates, after cooling again, in regular microscopic cubes. (Scherer, Kerner.) 8. Xanthin occupies the middle step between sarkin (hypo- xanthin) and uric acid. Sarkin G.H.N.O [0,oH4lT,OJ Xanthin O.H^N.Oj [C.oH^N^O^] Uric acid O^H^N^Os [C,„H,N,0 J . * Comptes rendus, Bd. 73, p. 47. Digitized by Microsoft® NORMAL OONSTITUENTS OF URINE, OBGANIO. 31 D. Detection. I give below a method whicli not only insures tlie detection of xanthin in urine, but also at the same time en- ables us to obtain kreatinin and considerable amounts of chemi- cally pure urea in one and the same portion of urine. 1. XantJiin. Fresh urine is treated with a mixture of baryta water and nitrate of barium in a decanting jar, till all of the phosphates and sulphates are precipitated. When the precipi- tate has thoroughly settled, the clear fluid is removed with a siphon, and evaporated in a large porcelain dish over a gas stove. The latter not only renders water baths for this sort of work superfluous, but also allows of a much quicker evapo- ration without ever bringing the fluid to boiling. The syrupy mother liquor, from about fifty liters of urine, is poured off from the salts crystallized out after cooling, diluted to four or five liters, treated with about a pound of ammonia, and precipi- tated with an ammoniacal solution of nitrate of silver. As soon as the precipitate is settled, the supernatant fluid is removed with a siphon, the silver compound is collected on a filter and washed with distilled water until the filtrate no longer reacts with chlorine. When this point is reached, the filter is laid on blotting paper and kept there until the moist precipitate can be readily removed, it is then put into a flask and dissolved by boiling in as little nitric acid of a specific gravity of 1"1 as pos- sible. In most cases a complete solution follows, and only a few flocculi of chloride of silver remain behind ; the heat is continued till the fluid, at first very dark colored, has become light yellow. Soon yellow flakes of nitrate of xanthin silver oxide separate from the filtrate. Since, however, the silver compound of xanthin separates from the nitric acid solution much more slowly than the corresponding sarkin compound, the fluid is allowed to stand at least eight to twelve days ; from the first a too great excess of nitric acid should be avoided. The nitrate of xanthin silver oxide is collected on a filter, washed and digested, for the removal of nitric acid, with ammo- nio-nitrate of silver. After washing again, the yellow-colored silver compound is suspended in water, and, after the addition of a little hydrochloric acid, heated to boiling and decomposed by sulphuretted hydrogen. The filtrate which is still colored yellow is decolorized completely by treating it with some well- extracted animal charcoal, and after concentration the chloride Digitized by Microsoft® 32 ANALYSIS OF THB URINE. of xantMn separates in small hard crystals. By repeatedly evaporating the chloride of xanthin with ammonia, and finally washing out the chloride of ammonium with cold water, pure xanthin is obtained. The amount obtained is very small — ^with less than one or two hundred pounds of urine the work should not be undertaken. The nitric acid solution, from which the nitrate of xanthin silver oxide was crystallized, contains the rest of the xanthin compound, and, as I believe, other silver com- pounds also. On the addition of ammonia, a considerable amount of gelatinous, yellow precipitate falls, with which a considerable amount of the silver xanthin compound is always mixed. 2. Kreatinin. The ammoniacal mother liquor, from which the xanthin was precipitated by nitrate of silver, is heated again on the gas stove, when the ammonia escapes, and the excess of sil- ver added separates at the same time. If, the fluid no longer smells of ammonia it is filtered, and the clear fluid evaporated to a syrup. After cooling, about an equal volume of alcohol is added, it is allowed to stand twenty-four hours, decanted from the nearly crystallized salts, and mixed with a concentrated neutral alcoholic solution of chloride of zinc, when, after a short time, very pure, faintly yellow kreatinin chloride of zinc preci- pitates, which is used for obtaining kreatin and kreatinin by the familiar method with freshly precipitated hydrated oxide of lead, etc. 3. Urea. The alcoholic mother liquor, from which kreatinin was precipitated, is mixed with an equal volume of pure nitric acid of specific gravity 1'2, and allowed to stand in the cold twenty-four hours to crystallize out the nitrate of urea. The crystalline mass is placed on porous tiles, allowed to dry, dis- solved in water and boiled with pure animal charcoal. The filtrate remains yellow, and after evaporation deposits large amounts of yellow nitrate of urea. All of the products of crystal- lization are dissolved in water, and the boiling solution treated with small amounts of permanganate of potassium until it has be- come absolutely colorless. After evaporation the nitrate of urea crystallizes out perfectly colorless. To obtain pure urea, the tiitrate is finally decomposed by freshly precipitated carbonate of barium, evaporated, most of the nitrate of barium allowed to crystallize out, the mother liquor brought to complete dry- Digitized by Microsoft® NOBMAL CONSTITUENTS OF URINE, ORGANIC. 33 ness, and the urea extracted, while cold, with five times its amount of alcohol (93 per cent.). After distilling off the alco- hol, the urea separates in masses of pure crystals. APPENDIX. HypoxantMn (SarMn). Hypoxanthin, or sarkin, e5H4]Sr4a [CoH^N.O^], which is of con- stant occurrence in the juice of muscle, has hitherto not been found in the urine with certainty, although Salkowsky succeeded in separating a body from normal as well as leuksemic urine, which corresponded with sarkin in its characteristics, except in a few particulars. Sarkin was certainly detected in the me- dulla of bone from leuksemic persons by Salkowsky, and also in fifteen pounds of normal calves' bones. The method above described by me for separating xanthin, serves for detecting the sarkin, the nitrate of silver compound of which differs from the corresponding xanthin one only by its being very much less soluble in nitric acid. The masses which separate imme- diately on cooling from the boiling nitric acid solution of the silver compound, will have some sarkin present. To separate it with certainty it is recrystallized, after the addition of one cubic centimeter of the nitrate of silver solution, once or twice from hot nitric acid, and that portion which first separates is collected on a filter, washed, and digested for a time with an ammoniacal silver solution to remove the nitric acid, filtered, washed, the precipitate suspended in water, heated to boiling, and decomposed with sulphuretted hydrogen. The colorless filtrate leaves, after evaporation, pure crystallized sarkin. Sarkin is distinguished from xanthin, especially in the fol- lowing particulars : 1. The nitrate of sarkin silver oxide completely separates from hot nitric acid immediately on cooling. The compound shows, under the microscope, long colorless needles, which do not blacken on exposure to light. The corresponding xanthin compound separates, after a long time, in scaly masses.* 2. Pure sarkin, after careful evaporation with nitric acid, * Zeitschrift fiir analyt. Chemie, Band 6, p. 33. 3 Digitized by Microsoft® 34 AWALTSIS OF THE UBI£fB. does not furnish a deep-yellow residue, but an almost colorless, or, at most, a light-yellow one, which, on the addition of hy- drate of sodium, becomes somewat darker, but not, as in the case of xanthin and guanin, red yellow. 3. Sarkin does not give, with hydrate of sodium and calcic hypochlorite, a green color. 4. Sarkin separates from hot water in a crystalline form xanthin, on the other hand, amorphous. (See § 5, B.) "Weidel found a new base in Liebig's meat extract, carnin, OjHsISTiOs + Hga, which yields, on heating with nitric acid, ni- trate of sarkin, together with some oxalic acid. Carnin con- tains, therefore, the elements of sarkin and of acetic acid : Carnin = G,He]SrA Sarkin ^ Q^^^.Q- Difference = OjHiOa = acetic acid ; but on account of its stability when treated with baryta water, it is not to be regarded as acetate of sarkin. If carnin or sarkin is heated with fresh chlorine water and a trace of nitric acid until the slight evolution of gas has ceased, then evaporated to dryness on a water bath, and the white residue exposed under a receiver to ammonia vapor, in a short time a dark rose-red color appears. The formula of carnin differs from that of theobromin only in possessing one atom more of oxygen. F. Baumstark * found first in the urine of a dog fed on benzoic acid, then in icteric, and finally, also in normal human Tirine, a new crystalline body by the following procedure : The urine, carefully concentrated to a syrup on the water bath, or over a gas stove, is, while it is still warm, mixed with large quantities of alcohol, the spirit is distilled off from the filtered alcoholic solution, the hippuric acid removed from the residue after acidifying with hydrochloric acid by shaking with ether, and the fluid thus freed after supersaturation with am- monia, completely precipitated with basic acetate of lead. The fluid filtered from the lead precipitate is freed from surplus lead by sulphuretted hydrogen, and evaporated to a syrup. * Berictt. der deutscli. chem. Gesellschaft, Band 6, p. 883. Ajonal. der Chemie, Band 173, p. 393. 4 Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. 35 The new body, together with urea, separates from this residue after long standing, and remains insoluble on treating the crys- talline mass with alcohol. The new hitherto nameless body crystallizes out of hot water in white prisms, similar to those of hippuric acid, which melt at over 250° C. Heated on plati- num foil, thick white fumes are evolved with dissemination of a peculiar odor. Heated in a small tube, the body yields an inflammable gas, which smells like ethylamin and blues litmus. The crystals dissolve with tolerable readiness in hot water, with difficulty in cold water and alcohol. They are insoluble in absolute alcohol and ether. Analysis gave the formula €3H»N,0 (C'eH^lSr.O,). It forms readily soluble salts with acids, but no compounds with bases. The solution is precipitated by mercuric nitrate. Lactic and paralactic acids form on treating it with nitrous acid ; boiling it with baryta water evolves at first one-half of the nitrogen in the form of ammonia, and afterwards the rest as ethylamin with separation of carbonate of barium. §. 6. Ueic Acid. Formula : -GsH^lSrA [C,„H,N,0,] r Carbon 35-73 Hydrogen 2-38 Nitrogen 33-33 L Oxygen 28-57 100-00 A. Presence. Uric acid is found in the urine of all classes of animals, and occurs even in the very lowest orders. The excre- ment of birds (guano), snails, reptiles, and insects is rich in uric acid. Besides in the urine, it was detected also in normal blood of hens, by Meissner, and after extirpation of the kidneys by Strahl and Lieberkiihn * and recently by Garrod.t Accord- ing to the latter, it appears constantly increased in the blood in gout. It has further been found in the spleen, lung tissue muscular juice of the heart, the pancreas, brain, and liver, and finally in gouty deposits. E. Bender J found on the surfaces * Strahl and Lieberkiihn. Harnsaure im Blute, etc., Berlin, 1848. fPrager Vierteljahresschrift, Band 5, S. 4, Abth. II., p. 13. i Journ, fiir prac. Chemie, 1866, III., p. 254. Digitized by Microsoft® 36 ANALYSIS OF TEE UBINK of the face, stomach, and liver of a body exlmined after two months' burial, small white spots, which consisted of uric acid crystals. The amount of uric acid in human urine is less dependent on the food taken, as is the case with urea, than on special inter- nal conditions of the economy. Under normal conditions, ac- cording to Becquerel, 0495 to 0-557 grams of uric acid are eliminated by a healthy man in twenty-four hours. According to my own experiments, instituted on a powerful healthy young man of twenty-three years of age, there was an average secretion of 364 grams of urea and 0-827 grams of uric acid in 2,000 cc. of urine in tw-enty-four hours. Further observations have shown me, however, that in the normal condition the amount of uric acid may vary considerably, and may fluctuate within twenty- four hours between 0-2 and 1 gram. According to Eanke, the proportion of uric acid to urea varies from 1 : 50 to 1 : 80 in twenty-four hours. An increase of uric acid results, first of all, from disturbed digestion, as well as generally insufficient nutri- tion. Moreover, it is found to be increased in all febrile condi- tions, and especially in affections of the respiratory organs and disturbances of the circulation. In a case of leukaemia Salkowsky * found, during a series of observations extending over thirty days, that the uric acid was permanently increased, not alone in percentage, but also absolutely, especially in rela- tion to the urea. An average of thirty estimations gave a pro- portion of uric acid to urea of 1 : 16-3, which is more than a threefold increase. If uric acid is taken into the body it is decomposed normally into carbonic acid and urea, but yields also oxalic acid, when- ever the process of oxidation has undergone a retardation in any way. B. Preparation. — 1. From Human Urine. Freshly filtered morning urine is treated with hydrochloric acid (20 cc. to 1 liter of urine), and allowed to stand forty-eight hours. The uric acid will be found separated in more or less deeply colored- crystals, which are specially adapted for microscopic study. 2. From Excrement of Serpents. The excreta of serpents are boiled with a solution of one part of potassic hydrate in twenty * Vircliow's Archiv, Band 50. Digitized by Microsoft® NOBMAL CONSTITUENTS OF UMINE, ORGANIC. 37 parts of water until the ammoniacal odor has disappeared. Car- bonic anhydride is conducted into the filtered solution until it is nearly neutral, and the acid urate of potassium, which is thus separated, is collected and washed with water. After washing, the potassium salt is dissolved in potassic hydrate, and the solution filtered into dilute hydrochloric acid, care being taken that the latter is always present in excess ; the precipitate is pure uric acid, which, after washing and drying, is obtained as a delicate light powder. C. Microscopic Properties. Uric acid appears in many different forms under the microscope, chiefly, however, as smooth tables of rhombic form. These are sometimes colored, are always of extraordinary transparency, and vary in size — often being by no means small. The tables are frequently modified, so that spin- dle-shaped crystals are formed by the rounding off of the obtuse angles, with which are mixed short barrel-shaped cylinders. Frequently, however, six-sided plates, rectangular tables, or rectangular four-sided prisms with abrupt terminations ap- pear; these often lie collected together in peculiar rosettes. Besides these, other modifications occur, as saw-shaped, fan- shaped, or tooth-shaped crystals. (Plate I., figs. 2 and 3 ; Plate n., fig. 4; Plate IH., fig. 1.) I succeeded in obtaining very manifold forms of uric acid, whose character could readily be seen by comparison with Fuhke's plates, by treating a normal urine with different amounts of hydrochloric acid. If the nature of any crystal is doubtful, however, it is very easy to bring it into the usual form ; it is dissolved on an object glass in a small amount of potassic hy- drate, and a drop of hydrochloric acid is added, when the usual tabular and spindle forms are seen to occur. D. Chemical Properties. Pure uric acid prepared from the ex- crement of serpents forms white, very light, delicate -feeling crystalline scales, which, seen under the microscope, show the above-described forms. It is without taste and odor, is very difficultly soluble in water (one part of uric acid requires four- teen to fifteen thousand parts of cold water, and eighteen to nineteen parts of hot water), the solutions obtained do not red- den litmus. In dilute hydrochloric acid it is quite as insoluble, and is not at all soluble in alcohol and ether. It is readily soluble in concentrated sulphuric acid without decomposition, Digitized by Microsoft® 38 ANALYSIS OF THE UBINE. but is precipitated from this solution again by diluting with water. 1. It is quite readily soluble in a solution of phosphate of sodium as well as in that of many other salts of the alkalies. It takes from these salts a part of the base, with which it com- bines, and thus gives rise to the formation of acid salts. It is contained in the urine in this form, together with the acid phosphate of sodium, which is the chief source of the acid re- action of urine. It is easy to obtain a fluid similar to urine, with an acid reaction, by dissolving uric acid in a warm solution of phosphate of sodium, and from this fluid crystals, of urate of sodium are deposited on sufficient concentration. (For the separation of the latter from the urine, see Sediments.) If the acid solution, which results from dissolving uric acid in phosphate of sodium, is allowed to stand a long time at a temperature of 20' to 30° C, after a few days bacteria form, the acid reaction diminishes, and the fluid gradually becomes alka- line. After eight to fourteen days all of the uric acid is decom- posed, and the fluid contains urea and carbonate of ammonium. Other products, as allantoin, oxalic acid, etc., do not appear to be formed in this decomposition. (Lex.) 2. If uric acid is heated in a glass tube it is decomposed, without, however, previously melting. It breaks up into urea, cyanuric acid which forms a sublimate, hydrocyanic acid, and a little carbonate of ammonium, which can be recognized by its odor. In addition peculiar oily products are observed, and a porous carbon containing nitrogen is left behind. 3. If uric acid, made into a pulp with water, is boiled with peroxide of lead, it decomposes into four bodies : carbonic an- hydride, allantoin, urea, and oxalic acid. The allantoin which is naturally present in the urine of calves, as well as the urea, can be easily obtained by crystallization and recognized, the oxalic acid remains in combination with the lead, while the carbonic anhydride escapes with efi'ervescence. According to Pelouze a little allanturic acid is formed also. It is not impro- bable that the urea which occurs in this decomposition is a further product of the oxidation of allantoin, and the carbonic acid a product of the oxidation of oxalic acid, so that the sim- plest decomposition of uric acid by peroxide of lead is into allantoin (OjHolSriOs) [OeHsNiOc] and oxalic acid. Digitized by Microsoft® NOBMAL CONSTITUENTS OF UBINB, OB&ANIO. S9 4 If hydriodic or hydroclilorio acid is allowed to act on uric acid in sealed tubes at 160° to 170° C, it decomposes into gly- cocoU, carbonic anhydride, and ammonia. (Strecker.) On pro- longed teating of uric acid witli douTile its weight of concen- trated sulphuric acid, in addition to glycocoU, a body similar to xanthin (pseudoxanthin) and hydurilic acid result. (O. Schult- zen and Filehne.) By this formation of glycocoU from uric acid, a close chemi- cal relationship between uric acid and hippurio acid, the char- acteristic constituents of the urine of carnivora and herbivora, is foreshadowed.* 5. Permanganate of potassium and ozone act very energeti- cally on uric acid ; allantoin, carbonic anhydride, oxalic acid, and urea are formed, or by ozone in an alkaline solution, urea, ammonia, oxalic acid, and carbonic anhydride. 6. If one part of uric acid is gradually added to four parts of concentrated nitric acid (specific gravity — 1'420), it is dissolved with effervescence, and finally the whole fluid solidifies to a crys- talline pulp. The uric acid at the same time decomposes into alloxan (GjHjNjOj) [OsHsNjOs] and urea ; the first separates in. the form of crystals, the latter by the simultaneous formation, of nitrous acid decomposes immediately into carbonic acid and nitrogen, which escape and cause the effervescence of the fluid. 7. If reducing agents, such as, for example, sulphuretted hy- drogen, hydrogen gas, etc., are allowed to act on the solution of alloxan, very soon crystals of a new body, alloxantin, separate (eaHiolSTjOjo) [C,6Hi„N"40,„]. This body is much more difficult to dissolve than alloxan, it crystallizes in oblique four-sided prisms, and becomes red when exposed to ammonia vapor. Alloxan and alloxantin give rise to the most important uric acid reaction. If a solution of alloxan and alloxantin is treated with ammonia, it becomes purple red, and after standing a time crystals of murexid are deposited. These form four-sided prisms, which reflect light of a cantharides-green color ; tritu- rated they form a brown powder, and dissolve in water with a deep purple color. It always serves for the detection of uric acid. * Aunal. der Chemie uud Pharm., Band 146, p. 143. Chem. Centralblatt, 1868, p. 499. Digitized by Microsoft® 40 ANALYSIS OF THE UBINE. 8. Uric acid treated with moderately dilute nitric acid dis- solyes, and alloxantin is found as the chief product of the reac- tion. If we carefully evaporate this solution almost to dryness, alloxan is formed from a part of the alloxantin by the further action of nitric acid. If now ammonia is allowed to act on the mixture, the beautiful color of murexid is produced. This color of murexid is rendered purple blue, by caustic potassa. By means of this reaction the smallest amounts of uric acid are readily detected. If the residue is treated immediately with potassic or sodic hydrate, instead of with ammonia, a magnifi- cent purple- violet solution is obtained, which, however, becomes paler on heating, and finally, before the fluid is entirely evapo- rated, loses its beautiful color completely. (Distinction from xanthin, see Xanthin.) According to Hardy, modified red alloxan forms first on evaporating uric acid with nitric acid, and on the addition of ammonia it is changed into red isoalloxanate of ammonium. 9. Uric acid forms salts with the bases which are more or less readily soluble in water ; the most soluble is the lithium salt. Crystalline uric acid is separated from these solutions on the addition of hydrochloric acid, acetic acid, etc. In concen- trated solutions the separation takes place immediately; in dilute, as for example urine, only after long standing, as twenty- four or thirty-six hours. The crystals are readily recognized under the microscope. For the different salts, see Sediments. 10. An alkaline solution of uric acid reduces nitrate of silver immediately, even in the cold. If a trace of uric acid is dis- solved in a solution of sodic carbonate, and a paper on which a drop of nitrate of silver solution has been allowed to spread is wet with it, a dark spot immediately forms, even when the uric acid is diluted one-thousand-times, but still smaller quantities, even to one five-hundred-thousandth of a gram, after a few seconds show a distinct yellow reaction without its being neces- sary to heat. (Schiff.) 11. If a solution of uric acid in potassic hydrate is added to an alkaline copper solution, a white precipitate of cupreous urate is formed. If the latter is heated to boiling with an excess of the solution of copper, the uric acid oxidizes, and red cupreous oxide separates, while the products of the oxidation of uric acid, allantoin, urea, and oxalic acid, remain in solution. Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, OBGANIO. 41 12. If a bromidized alkaline solution of hypochlorite of so- dium is allowed to act on uric acid, an intense rose-red fluid is formed. The color disappears after a time, especially if more of the bromine solution is added. (Dietrich.)* E. Detection. It is to be noticed here that urine which is undergoing acid fermentation frequently deposits uric acid in more or less deeply colored crystals. In diabetic urine, espe- cially, one finds not infrequently after a short time all of the uric acid as a red, sandy, crystalline powder on the bottom of the glass. 1. 100 to 200 cc. of urine are eyaporated in a porcelain evapo- rating dish on a water bath. If the urine contains albumen, it must first be coagulated by boiling after the addition of a drop of acetic acid, filtered, and the filtrate evaporated to a syrupy consistency. By frequently treating with alcohol the urea is extracted from the residue together with the extractive matters and the salts soluble in alcohol ; the uric acid, on the other hand, remains behind with the insoluble salts and mucus. The salts are removed by pouring over it a small amount of dilute hydrochloric acid, and uric acid is obtained alone with a small amount of mucus. The following tests are to be employed to insure its perfect recognition: a. A few drops of nitric acid are poured over a small portion in a. watch glass. The specimen dissolves more or less com- pletely on warming, and after evaporating on a water bath leaves a reddish residue behind. If this residue is moistened with dilute ammonia (one part to ten of water), the purple-red murexid appears instantly, which, by addition of a drop of potassic hydrate, becomes purple blue. If the amount of uric acid present is very small, an excess of ammonia can very easily hinder the reaction, therefore it is safer to bring a glass rod moistened with ammonia near it, and to allow the ammo- nia vapor to blow over the residue. The test thus performed will react certainly and beautifully with mere traces of uric acid. b. The remainder is dissolved in a few drops of potassic hydrate, in which the mucus will remain undissolved. From this solution of urate of potassium the uric acid is precipitated * Zeitscrift filr analyt. Chem., Band 4, p. 176. Digitized by Microsoft® 42 ANALTSIS OF THE URINE. in a crystalline form by the addition of hydrochloric acid, and is recognized under the microscope. 2. The following method is simpler : About 200 cc. of urine are treated in a beaker with 5 cc. of hydrochloric acid, and allowed to stand twenty-four to forty-eight hours. At the end of this time the uric acid will be found separated in the form of colored crystals, which partly float on the surface, and partly are deposited on the sides and bottom of the. glass. An exami- nation, under the microscope, as well as a test of the filtered crystals, with nitric acid and ammonia, will permit its easy recognition as uric acid. 3. If there is only a small amount of fluid to test for uric acid, it is to be poured on a shallow watch glass, and with from four to eight grams, six to twelve drops of strong acetic acid are to be added, and after a thread about an inch long is laid in the fluid, it is to be allowed to stand eighteen or twenty-four hours, at a temperaturte at most of 16° to 20° 0. At the end of this time the uric acid will have separated in crystals on the thread, which must, therefore, be examined microscopically. This method is particularly fitted to test the blood-serum of gouty patients for uric acid. (Garrod.) § 7. OsALUEic Acid. Formula : G8H4NA Carbon 37 •27 Hydrogen 3-03 Nitrogen 31-21 Oxygen 48-49 100-00 A. Presence. Schunk* first proved the occurrence of oxaluric acid, combined with ammonia, in normal urine. This discovery renders it more than probable that other members also of the large series of uric" acid derivatives occur in normal or pathological urine, whereby additional information in reference to physiology and pathology may be obtained. Oxaluric acid stands in close relation to uric acid, xanthin, * Proceed, of the Royal Society, vol. 16, p. 140. Zeitschrift flir analyt. Chem., Band 6, p. 499, and Band 7, p. 325. Digitized by Microsoft® NOBMAL CONSTITUENTS OF URINE, ORGANIC. 43 and guanin, and also to urea. Uric acid, treated with nitric acid, yields first urea and alloxan ; the latter by further oxida- tion gives, with the development of carbonic acid, parabanic acid, which is also obtained by treating guanin and xanthin with chlorate of potassium and hydrochloric acid. Parabanic acid becomes oxaluric acid by absorbing water, and this, on boiling with water, splits up into urea and oxalic acid. The following equations show the gradual decomposition of uric acid into urea, oxaluric acid, carbonic acid, and water : 1. e^H^N.Os + o + H,a = e,H,K A + GH^N^a [C,„H4N406 + 20 + 2H0= CsH,N,03 + C|H4N,0 J (Uric acid) (Alloxan) (Urea). [CJI.N.Os + 20= 0«H,]Sr,Oe + SCO J (Alloxan) (Parabanic acid). 3. e3HjNA+H,a=e3H4NA [CsH,N,0„ + 3H0 = CeH^N.Os] (Parabanic acid) (Oxaluric acid). 4. 03H4NA+Hsa=:eH4]sr5a+G,HA [C6H4N.O, + 2H0 = 0,H4]Sr,0, + C4H,0e] (Oxaluric acid) (Urea) (Oxalic acid). 5. GJI,Q, + Q=2G0, + 'R,Q [Gja.,0, + 20 =4C0j + 2H0] (Oxalic acid) (Carb. acid) (Water). B. Preparation. A solution of uric acid in warm very dilute nitric acid, when treated with ammonia, immediately after cool- ing, yields, on evaporation, crystals of oxalurate of ammonium. The same salt is obtained by boiling parabanic acid with am- monia, and evaporating the solution. Hydrochloric acid sepa- rates the oxaluric acid from a concentrated solution of oxalurate of ammonium, as a light, white, crystalline powder. 0. Microscopic Properties. If a drop of a solution of pure oxalurate of ammonium is evaporated on an object glass un- der the microscope, long prisms, with pointed ends, are seen, which unite to form beautiful double tufts, or more or less com- plete rosettes. If the salt is not perfectly pure, the tufts of needles remain small, and form spherical aggregations which ' Digitized by Microsoft® 44 ANALYSIS OF THE URINE. are studded on the periphery with fine, prominent, crystalline needles. If a drop of nitric acid is brought in contact with such crystalline aggregations, the rosettes of prismatic crystals change, while still maintaining their opposed position, into a warty clump of oxaluric acid crystals. If a solution of oxalurate of ammonium is treated with nitric acid, a white crystalline powder separates according to the con- centration, either immediately or after long standing, consisting chiefly of indistinctly defined oxaluric acid crystals. After short or long standing in the nitric acid fiuid, sometimes only after several days, the separated oxaluric acid disappears again, and a drop of this solution now allowed to evaporate on an object glass readily shows the characteristic forms of nitrate of urea under the microscope. D. Chemical Properties. Free oxaluric acid is a white, crys- talline powder having an acid taste, very difficultly soluble in water. The oxalurate of the alkalies, like that of ammonium, is soluble in water ; the other salts, on the other hand, are dif- ficultly soluble or insoluble. 1. An aqueous, tolerably dilute solution of oxalurate of am- monium, treated with chloride of calcium and ammonium, does not give rise to a precipitate ; the fluid remains perfectly clear. If the mixture is then warmed, there occurs very soon, far be- fore the boiling point, a cloudiness, and calcic oxalate separates in large quantities. This reaction gives, doubtless, the most delicate test, and with it incredibly small amounts of oxaluric acid can be detected with the aid of the microscope. If the solution was too concentrated, the precipitated calcic oxalate will be amorphous. Dilute solutions, however, especially when the fluid contains coloring matters, etc. (as, for example, a di- lute solution of oxalurate of ammonium in urine), give, when treated in this way, a precipitate of calcic oxalate, insoluble in acetic acid, and showing under the microscope the most beauti- ful quadrilateral octahedra. If the microscopic examination should show no well-formed crystals of calcic oxalate, it is easy to bring the amorphous into the crystalline form. For this pur- pose the precipitate is allowed to settle, the fluid is decanted from it, and it is dissolved in one to two drops of hydrochloric acid. If then the hydrochloric acid solution is tolerably diluted, and carefully covered with a layer of ammonic hydrate, on quiet Digitized by Microsoft® NOBMAL CONSTITUENTS OF URINE, ORGANIC. 45 standing, the two fluids gradually mix, and as soon as the calcic oxalate lias completely separated again, the microscope will show a greater or less number of the most beautiful quadrilat- eral octahedra. With care this reaction never fails, and with the very characteristic form of the calcic oxalate it is most deli- cate and decisive. 2. If a solution of oxalurate of ammonium is boiled with hydrochloric acid, in a few minutes oxalic acid can be detected by adding ammonia and chloride of calcium. 3. An aqueous solution of oxalurate of ammonium, with ni- trate of silver, does not give a precipitate immediately ; after a few minutes, however, fine crystalline needles separate, which on sufficient concentration at last fill the whole fluid, and under the microscope appear as very fine hair-like needles, ar- ranged in stars and rosettes. The silver salt does not blacken on exposure to the light, and readily dissolves in ammonia. The ammoniacal solution does not become reduced by boil- ing. 4. A tolerably concentrated solution of pure oxalurate of am- monium does not give a precipitate immediately when treated with sugar of lead solution. After a few minutes the mixture becomes cloudy, and oxalurate of lead separates as a heavy crystalline powder, which appears under high powers of the microscope, as very well formed four-sided prisms, with six end surfaces. If the oxalurate of ammonium is not quite pure, its aqueous, tolerably concentrated solution is treated with the lead salt, the precipitate which takes place immediately is fil- tered off, and the filtrate is left at rest, when the characteristic crystals will soon separate. According to my experience the lead salt in the crystalline form is more easily obtained from impure material than the silver salt. 5. The addition of chloride of calcium or chloride of zinc to moderately concentrated solutions of oxalurate of ammonium causes crystalline deposits of the salts of these metals to sepa- rate after long standing; these also show very characteristic forms under the microscope. E. Detection. The urine is filtered through animal charcoal to separate the oxalurate of ammonium. This salt is retained by the charcoal, and can be withdrawn by boiling it with alcohol. I use the apparatus shown in the accompanying figure, which, Digitized by Microsoft® 46 ANALTSia OF TEE URINE. Fig. i. in fact, allows several Imndred liters of urine to be used with little oversight. The apparatus (fig. 1) is intelligible without a description ; the pipette, A, of about 400 cc. capaci- ty, is filled with finely gra- nulated animal charcoal, such as is used in sugar manufactories. The screw of the stop-cock, C, is reg- ulated so that the urine runs off in drops, and dur- ing twenty-four hours six- teen or twenty liters pass through the charcoal. If the decolorizing power of the charcoal, covered with a new piece of fine linen from time to time to catch the epithelium, etc., ceases, the pipette is emptied and filled with new charcoal, so that the filtration can be continued fqr weeks. The charcoal saturated with coloring matters, etc., is next washed with dis- tilled water, until the fil- trate no longer reacts for chlorine and phosphoric acid ; it is then dried in the air, and finally is repeatedly boiled with alcohol until the latter is no longer colored yellow. Wash- ing and boiling require some patience, yet may be successfully performed. The greater part of the alcohol is next distilled off from the golden-yellow alcoholic solution, the rest of the fluid is evaporated in a porcelain dish on a water bath, either in the open air or under a hood with a good draught, since a fearful urinous odor, which persistently sticks to the clothing, is evolved by it, such as I do not ever remember to have experienced in so great a degree in all my many labors with urine. On treating the resi- due with lukewarm water, a tenacious fatty mass remains be- Digitized by Microsoft® JTOBMAL C0N8TITUENT8 OF UBINE. ORGANIC. 47 hind, in wliicla Scliunk lias found a crystalline fatty acid. The aqueous brown solution, however, yields after evaporation a syrupy residue, from which, after long standing in the cold, crys- talline oxalurate of ammonium separates. To shorten this pro- cess I have made use of dialysis through parchment with the best results. Even if the separation is not absolutely complete, the sufficiently concentrated diffusate soon solidifies to a crys- talline mass. The rest of the syrupy mother liquor is extracted -with absolute alcohol, the crystalline residue is washed with al- cohol a few times and then dissolved in hot water, the solution -obtained is digested with a very small amount of purified animal charcoal, filtered, and the colorless filtrate evaporated, when on sufficient concentration pure oxalurate of ammonium separates. The yield is only very small, yet I obtained from 100 to 150 liters of urine, according to the method described, a sufficient amount to recognize this interesting body by all of its character- istic qualities, and to compare it with the pure salt prepared Jrom parabanic acid. § 8. HiPPUBio Acid. ' Carbon 60-34 Formula: e5H,Na3 [CANOe] ' Hydrogen Nitrogen _ Oxygen 5-03 7-82 26-81 100-00 A. Presence. Hippurio acid is present chiefly in the urine of herbivora. It is found in human urine in normal as well as in abnormal conditions. Bence Jones found in the twenty-four hours' urine of a small man 0-32 grm. of hippuric acid and 0-5 grm. of uric acid ; in a heavy man, 0-42 grm. of hippuric acid, and 0-82 grm. of uric acid. Before meals the urine of both persons always contained less hippuric acid and also less uric acid in one thousand parts of urine than after meals. Thudi- cum found on the average in the urine of an adult in twenty- four hours 0-169 to 0-315 grm., and even as much as 1-0 of hip- puric acid. After taking plums the twenty-four hours' amount increased to 2-212 grm. Hallwachs obtained from the twenty- Digitized by Microsoft® 48 ANALYSIS OF TSE UBIMK four hours' amount of urine of different persons, even in a pre- ponderance of meat diet, nearly I'O grm. of Mppuric acid. Hippuric acid is found to be increased by a purely vegetable diet, especially after taking plums, red whortleberries, mulber- ries, asparagus, and further, after the internal use of benzoic acid, oil of bitter almonds, toluol, cinnamic acid, kinic acid, etc. Succinic acid, on the contrary, causes no increase of hip- puric acid, according to Hallwachs, but according to Meissner is eliminated with the urine unchanged. In several diseases, especially in high fevers and in diabetes, an increased secretion of hippuric acid appears to occur. Besides in the urine, hip- puric acid has been detected in small amount in the suprarenal capsules of the ox, in diseased human blood, and also in icthy- osis scales. The source of hippuric acid in the urine may be twofold ; first, bodies may be ingested with the food which are converted into hippuric acid in the economy. Hallwachs was unable to find benzoic acid in the ordinary grass fodder of the cow, but Zwenger and Siebert found in bilberry bushes toler- able quantities of kinic acid, as did also Schwarz and Oehren in different sorts of galium ; we know that kinic acid is changed into hippuric acid in the economy. If kinic acid is wide-spread in the vegetable kingdom, which can scarcely be doubted, the great richness of the urine of herbivora in hippuric acid is thereby very simply explained. But in the oxidation of albu- men in alkaline solution with permanganate of potassium, con- siderable amounts of benzoic acid appear, wherefore it is more than probable that at least a part of the hippuric acid discharged with the urine is also formed by the metamorphosis of nitro- genous constituents of the body.* According to the investigations of Meissner and Joly,t the urine of rabbits, after being fed on meadow hay and clover, con- tains much hippuric acid as well as urea. The former almost entirely disappears from the urine, however, after exclusive feeding with carrots {Daucus carota), and is immediately re- placed by succinic acid to such an extent that benzoic acid does not appear. Meissner and Joly arrive at the conclusion * Meissner and Shepard, TJntersuchungen ilber das Entstehen der Hippur- saure, Hannover bei Hahn, 1866. J. Erdmann, Chem. Centralblatt, 1866, p. 397. f Zeitscbrift fur Cbem., Neue Polge, Band I., p. 230. Chem. Centralblatt, 1866, p. 339. Digitized by Microsoft® NOBMAL CONSTITUENTS OF UBINE, OBOANIG. 49 that the formation of hippuric acid, and what appears to be the chief thing, of benzoic acid, is directly dependent on the character of the food, and is not a characteristic of metamor- phosis in the herbivorous organism independent of the charac- ter of the food. According to the investigations of Wildt, feeding on Leontodon taraxacum (dandelion) causes a not incon- siderable increase of hippuric acid in the urine. B. Microscopic Properties. If a hot saturated solution of hip- puric acid is allowed to cool rapidly, the crystals under the microscope appear in the form of fine needles and hairs. It separates in regular, well-formed crystals, however, from a dilute cold saturated solution. It forms in this way, milk-white, semi- transparent, four-sided prisms and pillars, which are terminated by two or four surfaces. The typical form is always a vertical rhomboid prism. (Plate I., fig. 1.) Single crystals at times re- semble those of ammonio-magnesian phosphate, from which, however, hippuric acid is easily distinguishable by its chemical behavior. C. Preparation. Fresh horse or cow urine (5 to 6 liters) is boiled with an excess of milk of lime a few minutes, then filtered, the clear solution of hippurate of calcium is quickly evaporated to an eighth or a tenth of its original volume, and treated with hydrochloric acid. After twenty-four hours the hippuric acid is crystallized out, is dissolved again with milk of lime to purify it, and is allowed to crystallize again from the filtrate after the addition of hydrochloric acid. If it is not colorless even then, it can be treated in aqueous solution with well-burned animal charcoal. After the filtrate cools, it then separates in the form of colorless, transparent, long crystals. The mother liquor yields after evaporation a second crystal- lization. Loewe treats the fresh urine with sulphate of zinc, evaporates it together with the precipitate which takes place to one sixth, filters rapidly, and separates the hippuric acid from the filtrate by hydrochloric acid ; it is then to be recrystallized to purify it. This method gives a very pure preparation. An efficient procedure to purify colored hippuric acid is given by Gossmann. The crystals are dissolved in a sufficient amount of dilute sodic hydrate, and a solution of permanganate of potassium is added, drop by drop, to the fluid heated to boil- 4 Digitized by Microsoft® 50 ANALYSIS OF THE URINE. ing, until a portion filtered off gives a white precipitate with hydrochloric acid. The entire filtrate, while still hot, is treated with a slight excess of hydrochloric acid and allowed to crys- tallize. D. Ghemiccd Properties. — 1. Hippuric acid is odorless and has a slightly bitter taste. It requires six hundred parts of cold water to dissolve it, but much less hot water. Alcohol takes it up readily, ether with more difl&culty but yet completely. The solutions redden litmus strongly. 2. Hippuric acid heated in a small glass tube melts to an oily liquid. If it is allowed to cool it solidifies to a milk-white crystalline mass. On being heated more strongly it decom- poses, benzoic acid and benzoate of ammonium sublime, and at the same time is observed the formation of oily red drops, which diffuse a peculiar odor similar to that of fresh hay ; after cool- ing they harden and are soluble in alcohol and ammonia, but not in water. If the heat is increased to nearly a red heat, an intense odor, like that of hydrocyanic acid, is developed, and a porous charcoal remains behind. This property is very char- acteristic of hippuric acid, whereby we can recognize it readily and distinguish it from uric acid and benzoic acid, with the latter of which it has very much resemblance. If in this dry distillation the heat is not raised above 250" the hippuric acid yields only benzoic acid colored pale red by some foreign sub- stance, traces of hydrocyanic acid and a liquid body, nitro- benzol, which has the greatest resemblance in odor to oil of bitter almonds. 3. If dilute mineral acids are allowed to act on hippuric acid it is not changed, but is, however, on heating with concentrated hydrochloric, sulphuric, or nitric acids. With these it under- goes a peculiar decomposition ; we find that crystalline benzoic acid has separated after cooling, and there remains dissolved in the fiuid, combined with the mineral acid, a body which, when free, has a feebly acid reaction, glycocoU, G^HsNaj [C4H5NO4]. , [C,,H,NO„ + 2H0 = C„He04 + 04H,N04] (Hippuric acid) (Benzoic acid) (Glycocoll). 4 In contact with fermenting or putrefying substances hip- puric acid becomes converted into benzoic acid, therefore it often Digitized by Microsoft® NOBMAL CONSTITUENTS OF UBINE, OBGANIG. 51 happens that it is no longer possible to separate it from old urine ; the benzoic acid formed volatilizes readily with the steam as soon as a little hydrochloric acid is added to the urine in evaporating it. 5. If nitrous acid is allowed to act on hippuric acid, or nitric oxide gas is conducted into a solution of hippuric acid in nitric acid, it becomes, with the evolution of nitrogen, converted into an acid free from nitrogen, benzoglycolic acid, OgHjOi [dsHsOgJ. The same decomposition occurs when hippuric acid is dissolved in an excess of dilute potassic hydrate, and the solution is treated in the cold with chlorine gas until no more nitrogen is evolved. 6. Hippuric acid forms crystaUizable salts with bases, and can be separated from solutions of its salts after sufficient con- centration by hydrochloric acid in the form of long needles. 7. If boiling concentrated nitric acid is allowed to act on hippuric acid, the solution evaporated to dryness, and the resi- due introduced into a small glass tube and heated, an intense odor of nitrobenzol, similar to that of bitter almonds, is de- veloped. Benzoic acid gives the same reaction. With cinna- mic acid the peculiar cinnamon odor conceals every other. Since even mere traces of nitrobenzol diffuse for a tolerably long time a powerful odor, this reaction is applicable to the de- tection of even very small amounts of hippuric acid. (Lticke.) Albumen, gluten, uric acid, grape sugar, salicin, salicyluric acid, choloidic acid, anisic acid, pyrogallic acid, kinic acid, pic- ric acid, naphtalin, phtalic acid, indigo, and isatin do not give this reaction. E. Detection. — 1. 800 to 1,000 cc. of urine are evaporated on a water bath almost to dryness, the residue is rubbed up with powdered baric sulphate, acidulated with hydrochloric acid, and extracted completely with alcohol. After neutralizing the alcoholic extract with sodic hydrate, the greatest part of the alcohol is distilled off, and the syrupy fluid which remains is, after the addition of oxalic acid, evaporated to dryness on the water bath with constant stirring. The dried mass is then suf- ficiently exhausted with large amounts of ether, to which some alcohol has been added, and the ethereal solution is distilled al- most to dryness. The crystalline residue is then treated, while hot, with milk of lime to remove the oxalic acid, filtered, the Digitized by Microsoft® 52 ANALYSIS OF THE UBINE. filtrate evaporated to a very small volume, and then feebly acid- ulated with hydroohloric acid. After some time the hippuric acid crystallizes out. The crystals are to be tested chemically and microscopically. Very small amounts of hippuric acid are detected by the nitrobenzol reaction. (Chemical Properties, 7.) If, however, the urine is rich in hippuric acid, for example after taking benzoic acid, it is possible to obtain crystals of hip- puric acid from it after evaporation to a syrupy consistence, by treating it with a little hydrochloric acid ; these crystals are easily separated from the uric acid, which is deposited at the same time, by means of hot water. 2. The following method of Meissner gives an easy and sure means of finding hippuric acid, and at the same time detecting any succinic acid present. 1,000 to 1,200 ce. of urine are precipi- tated carefully with strong baryta water, the excess of baryta water is removed by a few drops of sulphuric acid, of which an excess is to be avoided, and then filtered. The filtrate, accu- rately neutralized with hydrochloric acid, is then evaporated on a water bath to the consistency of a thick syrup, and the neutral residue, while still hot, is added to 150 or 200 co. of absolute alcohol in a closed glass vessel. Any succinic acid salts are precipitated together with the chloride of sodium, etc., while the hippuric acid salts remain in solution. After repeated agi- tation, as soon as the precipitate has settled well the alcoholic solution is decanted, and the alcohol completely driven off on the water bath, the syrupy residue, which on cooling solidifies to a crystalline mass, is put into a closed vessel while it is still hot, acidulated with hydrochloric acid, and the hippuric acid extracted by shaking with not too small amounts of ether (100 or 150 CO.). After the ether is distilled off, the residue is di- luted with water, and heated to boiling with a little milk of lime. The hippuric acid separates from the concentrated fil- trate, after the addition of hydrochloric acid, in beautiful crys- talline rosettes ; they can be obtained entirely free from color by treating with pure animal charcoal. Succinic Add. Since, according to the investigations of Meiss- ner and Shepard,* succinic acid also occurs in normal urine. * Meissner and Shepard, Untersucliuiigen ilber das Entstehen der Hippursa- ure, etc., Hannover, 1866. Digitized by Microsoft® FORMAL CONSTITUENTS OF URINE, ORGANIC. 53 regard must be paid to it in the qualitative analysis of urine.* Meissner and Shepard found succinic acid normally in the urine and in the blood : they found it in the urine, sweat, and saliva, after taking benzoic acid, and increased in the blood after the absorption of kinic acid. Succinic acid taken internally, how- ever, causes no increased secretion of hippuric acid, but in not too small doses is eliminated unchanged in the urine. Since, according to Pasteur's and my own numerous investi- gations, wine and other fermented drinks contain not inconsid- erable quantities of succinic acid, and the latter, at least in part, goes over into the urine unchanged, we have a really fre- quent source for the occurrence of this acid in normal urine. Meissner and Joly t found considerable succinic acid in the urine, with exclusive meat and fatty diet ; a diminution, and even disappearance of it with vegetable diet, and generally with insufficient nourishment. Succinic acid is formed in the econ- omy also by the reduction of malic acid. It occurs in rabbits after feeding on carrots {Daucus carota), also after the exhibi- tion of malate of calcium. Malate of sodium, however, yields only very little succinate, but becomes, for the most part, con- verted into the carbonate. Hilger and Koch found large amounts of succinic acid, to- gether with ammonia, after taking asparagus. There is no doubt that succinic acid and ammonia are formed from the as- paragin of the asparagus, which does not go over into the urine unchanged, but undergoes the same decomposition in the econ- omy as in the hands of the chemist. The saline mass precipitated from concentrated urine by ab- solute alcohol serves for its detection (see above, 2). After this has been thoroughly washed with alcohol, and finally pressed, it is dissolved in as little hot water as possible, hydro- chloric acid is added, and the succinic acid present is extracted by shaking with ether (100 to 150 cc). After distilling off the ether a brown mass remains, from which succinic acid crystal- lizes out with difficulty. I have found that treatment with nitric acid, by which the succinic acid is not attacked, is sufficient to * Salkowski, from his own numerous investigations, cannot acknowledge the occurrence of succinic acid in human urine as proved. Archiv der Physiolo- gie, Band 4, p. 95. f Loc. cit. Digitized by Microsoft® 54 ANALYSIS OF THE UBINK purify it. For this purpose, the ethereal extract is diluted with water, heated to boiling, and treated, while boiling, with pure nitric acid, drop by drop, until the fluid has a barely percepti- ble yellow color. The succinic acid readily crystallizes from this solution, after concentration. The crystals are placed on blotting-paper, the mother liquor is absorbed, and the slightly yellow acid is used for the following reactions : 1. A portion is sublimed in a small test tube. Succinic acid sublimes at 120° to 130°. 2. The remainder is dissolved in a little water, and the solu- tion obtained divided into two parts. One part is added to a mixture of alcohol, chloride of barium, and ammonia, when a white deposit of succinate of barium results. The second half is heated to boiling with an excess of carbonate of magne- sium, filtered, and treated with a few drops of a neutral solu- tion of ferric chloride, whereupon a voluminous brown precipi- tate of succinate of iron results. If the succinate of iron is decomposed, after washing, by heating with ammonia, the neu- tral filtrate gives, with a solution of nitrate of silver, a precipi- tate of succinate of silver. The silver salt is decomposed by sulphuretted hydrogen, and succinic acid is allowed to crystal- lize from the filtrate. (Funke, 2" Aufl., Taf. II., fig. 5.) 3. Its behavior with the acetate of lead is very characteristic. The precipitate which first takes place dissolves readily and completely in an excess of the reagent, but it separates again on warming and shaking as a heavy crystalline powder. I succeeded by this method in detecting very small quanti- ties of succinic acid, after it had been added to 800 or 1,000 cc. of normal urine. Salkowsky prefers to extract the succinic acid with ether. For this purpose the urine is precipitated with baryta, the excess of baryta is removed by sulphuric acid and evaporated. The concentrated solution is then strongly acidulated with sul- phuric acid and shaken several times with ether. It is puri- fied as above. 4 Schultzen proposed with good result the following proce- dure for detecting hippuric acid in icteric urine. The urine is precipitated with acetate of lead, and the filtrate treated with sulphuretted hydrogen and then evaporated. The residue is extracted with alcohol, the extract evaporated, and the hippuric Digitized by Microsoft® NOEMAL CONSTITUENTS OF UBINE, ORGANIC. 55 acid removed from the residue, after addition of hydrochloric acid, by shaking with ether. After evaporating the ether it is taken up with water, shaken with animal charcoal, and the fil- trate concentrated on the water bath, when quite pure crystals of hippuric acid separate. If this is not the case, the residue is dissolved in water, and a drop of basic acetate of lead solu- tion added, whereby all of the extractive matters and any ben- zoic acid present are removed. The filtrate is freed from lead, evaporated, and after cooling treated with hydrochloric acid which separates the hippuric acid. "Without the previous pre- cipitation with sugar of lead, often only benzoic acid is obtained from icteric urine. § 9. Phenol. (Carbolic acid, Phenylic acid, Phenylic alcohol.) T? 1 nTT--^ r Carbon 76-93 Formula : ejIsO I -rr i a ,r. rn TTr. 1 Hydrogen 640 iyj,,u.,v,\ L Oxygen 16-67 100-00 A. Presemx. Phenol was detected by "Wohler in the castor, and was later found by Stadeler, together with taurylic, damo- lic and damaluric acids as a constant constituent of the urine of the cow, human being, and horse. Only a very small quantity of this acid can be separated from human urine, and it is some- what doubtful whether this poisonous acid exists preformed in the urine, or is first formed during its isolation. According to recent investigations of Buliginsky * carbolic acid is in fact a product of the decomposition of a yet unknown constituent of the urine, which is soluble in alcohol, and is not precipitated by the acetate or basic acetate of lead and ammonia, but yields carbolic acid by the action of dilute mineral acids. After the external as well as internal use of carbolic acid, according to Almen,t E. Salkowski,^ and others, it appears in the urine which frequently assumes an olive-green, deep dark- brown, or even black color, and in the same way, according to * Hoppe-Seyler, Med. Chem. Mittheilung. , Heft 3, p. 334. f Neues Jahrbucli d. Pharm., Band 34, p. 111. :j; Pfiiiger's Archiv, Band 5, p. 335. Digitized by Microsoft® 56 ANALYSIS OF THE URINE. the investigations of Schultzen and Naunyn,* benzole changes into carbolic acid in the economy and appears as such in the urine. B. Chemical Properties. In a completely anhydrous state phenylic acid crystallizes in long colorless needles, which melt at 37'5° C. and boil at 183° C. The acid smells like smoke, acts as a caustic, and is poisonous. It is difficultly soluble in water, easily soluble in alcohol and ether. The solution coagulates albumen, and has a strong antiseptic action. 1. Nitric acid . allowed to act on phenylic acid, forms first nitro-, then binitro-, and at last trinitro-phenylic acid, which is known under the common name of picric acid or Welter's bitter, and can be produced from indigo, salicin, etc., by treating with nitric acid. 2. JPerric salts occasion in a solution of phenylic acid a violet color, playing into blue, which -after a time, changes to a dirty white turbidity. 3. Nitrate of silver, and also mercuric oxide, are reduced by phenylic acid. 4. A pine splinter, soaked in an aqueous solution of phenylic acid, and then dipped for an instant into dilute hydrochloric acid, becomes colored deep blue in a few moments after expo- sure to the rays of the sun. The color obstinately resists the action of chlorine ; it becomes lighter to be sure, but returns again when the splinter is dipped in dilute hydrochloric acid. 5. An aqueous solution of phenylic acid, treated with ammo- nia and calcic hypochlorite, becomes, on heating, a beautiful blue color. (K. Lex.) To the fluid to be tested a quarter of its volume of ammonic hydrate is added, then a few drops of the calcic hypochlorite solution (one part of calcic hypochlorite to twenty parts of water), and the mixture is warmed a little, but not to boiling. If the phenol is in large quantity the blue color appears im- mediately ; if its quantity is small a few minutes to a quarter of an hour are required. Too high a temperature, and also too much calcic hypochlo- rite interferes with the reaction; great care must be taken, therefore, in regard to the latter point. (Salkowski.) * Eeicliert's und Du Bois-Reymond's Archiv, 1867, Heft 3. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. Ql 6. A solution of phenol, heated to boiling with a solution of mercurous nitrate which contains a trace of nitrous acid, gives an intense red mixture, and in concentrated solutions there is a rapid separation of metallic mercury. The reaction is still very distinct when diluted one part in sixty thousand. (Plugge.) 7. A dilute aqueous solution of phenol, treated with an excess of bromine water, gives rise immediately to a yellowish- white flocculent precipitate of tribrom-phenol. On sufficient addition of bromine water the precipitate disappears at first. The washed precipitate, treated in a test tube with a little sodium amalgam and water, and warmed, evolves, if the fluid is treated in a watch glass with dilute sulphuric acid, the characteristic odor of free phenol. This reaction is very delicate. (Landolt.) Together with phenylic acid Stadeler found a series of other acids very similar to it. These are : 1. Taurylic Acid OiHgO LC^HgOs] ? which would be isomeric with anisol. It differs from phenylic acid by its higher boil- ing point, and by giving, with concentrated sulphuric acid, a fixed compound which separates in delicate white tooth-shaped masses, which gradually collect together into spherical ones. 2. Bamcduric Acid CH^O, [OhHi^O,]. This is an oily fluid similar to valerianic acid, heavier than water, but dissolving in it, however, to a slight extent, giving a strong acid reaction. This acid forms, with bases, well-characterized salts. The barium salt crystallizes in prisms, often joined together into tufts, which dissolve in water, giving a turmeric brown solution. The salt is fusible, and leaves behind, after ignition, carbonate of barium in the form of the original salt ; it contains 39 '18 per cent, of barium. The silver salt forms a white powder, which does not change on exposure to light ; it contains 49 "36 per cent, of oxide of silver. Basic acetate of lead also gives, in the solution of damaluric acid, a white precipitate, which appears under the microscope in the form of fine prisms collected into spheres. 8. Damolic Acid. This acid has been least investigated of all ; it is also oily, heavier than water, slightly soluble in it, and forms a crystalline barium salt, fusible on being heated, and which contains 27"50 per cent, baryta. The damolic acid salt crystallizes first out of a solution of damolurate and damolate of barium. Digitized by Microsoft® gg ANALTSIB OF THE URINE. Detection and Separation of these Foub Acids. 1. Separation of the Adds collectively from the Urine. Fresh cow urine (80 lbs.) is mixed witli calcic hydrate, boiled once, drawn off from the excess of lime, and evaporated to one- eighth. The filtrate is treated with hydrochloric acid after being well cooled, and the mother liquid, poured off from the hippuric acid, which has separated after twenty-four hours, is distilled. By repeated rectification of the milky fluid obtained by the first distillation, an oily, faint yellow liquid is finally ob- tained, which, for the most part, sinks to the bottom of the water in the receiver. In this oil phenylic acid can be readily detected by the reaction with ferric chloride, as well as by coloring a splinter of pine blue. The amount in human urine is very small.* 2. Separation of the Acids singly. The oil, with the water obtained, according to 1, is treated with a weighed excess of potassic hydrate, and subjected to distillation. A nitrogenous, strongly smelling oil, which has not been examined closely, is obtained in the distillate. So much sulphuric acid is added to the residue in the retort that five-sixths of the potassic hydrate used is saturated, and it is then distilled so long as a precipitate is produced in the dis- tillate by basic acetate of lead. By repeated distillation of the fiuid obtained over common salt, the greatest part of the acids are finally obtained in an oily form, and only a very small amount of an aqueous solution, with a very strongly acid reac- tion, remains. To separate this body with an acid reaction, the distillate is saturated with carbonate of sodium, frequently shaken, during twelve hours, and the oily layer separated from the sodium salt by extracting with ether. a. Acids which do not form compounds with carbonate of sodium. The ether is distilled off from the ethereal solution obtained according to' 2, and the residue once more subjected to distilla- tion with strong potassic hydrate. The potassium compound ■* Annal. der Chemie u. Phann., Band 97, p. 134. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. 59 which remains behind is decomposed with bicarbonate of potas- sium, and the distillate obtained completely dehydrated with chloride of calcium. By fractional distillation the greatest part, which consists of phenylic and taurylic acid, goes over between 180° and 195° C, and they can only be incompletely separated further by repeated fractional distillation. The chief difference between the two, besides the high boiling point of taurylic acid, lies in their behavior with concentrated sul- phuric acid, with which taurylic acid unites to form a solid compound, and phenylic acid, on the contrary, forms a fluid compound. b. Acids which form compounds with carbonate of sodium. The solution of the sodium salt, which was freed from the phenylic and taurylic acids by ether,, is evaporated, treated with sulphuric acid, and distilled. The distillate, which smells like butyric acid, separates into an oily and an aqueous layer. The whole is boiled with an excess of carbonate of barium, and allowed to crystallize. By fractional crystallization different barium salts, containing varying amounts of barium, are ob- tained (27 to 41 per cent, of barium). That acid is the chief constituent whose barium salt contains something over 39 per cent, (third, fourth, and fifth crystallization). This acid is the damaluric. (See Damaluric Acid.) The second acid, whose barium salt contains 27'4: per cent, (first and second crystalliza- tion), is damolic acid. (See Damolio Acid.) The other barium salts (evaporated mother-liquor) are mix- tures of damoluric acid with another barium salt: whether the acid in this salt is butyric, valerianic, or still a new one, has not yet been proved. In its preparation from human urine, the quantity obtained is very small indeed, and if perfectly fresh urine has not been taken for the examination, a considerable quantity of acetic is always obtained. C. Detection of phenol in human urine. The urine is strongly acidulated with tartaric acid, and about one-half of it is distilled off on a sand bath. The distillate obtained is shaken twice with many times its volume of ether, which extracts the phenol present. The phenol which remains behind after distilling off the ether is dissolved in a few cubic centimeters of water, and this solution is used for the above-mentioned reactions, of ' Digitized by Microsoft® 60 ANALT8I8 OF THE UBINE. wMcli those of Landolt, Lex, and Plugge are to be especially recommended. (Salkowski.) Landolt uses the above reaction, precipitation of the phenol as tribrom-phenol by bromine water, also for proving its pres- ence in normal urine. If human urine (500 cc.) is directly treated with an excess of bromine water, it usually becomes turbid, and after standing several hours a brownish flocculent deposit collects at the bottom of the glass. If this is collected, washed, and treated with sodium amalgam, the unmistakable odor of phenol is apparent. But since bromine water decomposes paraoxybenzoic acid with the formation of tribrom-phenol, and salicylic acid with bromine water yields dibrom-salicylic acid, which is decom- posed by sodium amalgam, and phenol set free, Maly con- siders that the behavior of urine with bromine water is not sufficient proof of the preexistence of phenol in normal urine. According to the above-described procedure of Salkowski, phenol was detected after its internal use (0'3 to 0*9 grams per day) in every 200 cc. of urine during twenty-two days in five patients, and after its external use four times in three patients. § 10. Ueinaex Coloeing Mattees. I. TTROBIIjIN. (m. jaff^.) A. Presence. M. Jaffe* found urobilin in normal as well as in pathological urine, and also in the bile. This pigment is dis- tinguished by characteristic spectroscopic properties, and also by the beautiful fluorescence which it shows under certain cer- cumstances and by which its preexistence in the urine can be readily verified. The high-colored urine of fever patients is especially rich in this pigment, but it was also detected in forty-five different urines of healthy individuals, so that we may well call urobilin a normal constituent of urine. B. Separation and Properties. All high-colored urine of fever patients shows on spectroscopic examination t with great dis- *ArcMvfurpathol. Anatomie, Band 47, p. 405. Zeitscliiift fiiranalyt. Chem., Band 9, p. 150, und Band 3, p. 345. f For the method to be used in suoh examinations, see under the head of Blood. Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, OBGANIO. 61 tinotness, frequently only after diluting with water, an absorp- tion band, y, between the Frauenhofer lines b and F, besides a characteristic change of color on the addition of alkalies. To render the fluorescence apparent, as well as to separate the pigment from such urines, the following procedure is to be adopted. The urine is treated with a not too small excess of ammonia, filtered, and the filtrate completely precipitated with chloride of zinc solution. The voluminous red or red-brown . zinc precipitate is washed first with cold and then with hot water until the chlorine reaction disappears, it is then boiled with alcohol, and finally dried with gentle heat. After pulver- izing the mass, it is dissolved in ammonia, and the solution precipitated with acetate of lead. The precipitate, which is almost always intensely red, is washed with cold water for a short time, dried, and then decomposed by alcohol containing sulphuric acid. The acid solution of the pigment thus ob- tained has the following characteristics : 1. When concentrated it is brown, when dilute it becomes reddish yellow at first, and later rose red. 2. On spectroscopic examination of the concentrated solution the spectrum from the violet end up to about the line b is completely dark ; on dilution the darkest part gradually bright- ens up, and there finally remains an absorption band, y, with indistinct edges between the lines b and F. 3. On the addition of ammonia the red-yellow or red color of the acid solution becomes bright yellow, and finally changes to a greenish tinge. The original specimen of urine shows the same change of color on the addition of ammonia. 4. The ammoniacal solution frequently shows a marked green fluorescence, which is brought out or strengthened by the addi- tion of chloride of zinc. 5. The alkaline solution of the pigment shows a very char- acteristic absorption band, S, between the lines b and F, but nearer to b than the band, y, of the acid solution. This band, S, is feeble when ammonic hydrate is used, but stronger with sodic or potassic hydrate. The ammoniacal solution shows the band immediately with great sharpness after the addition of chloride of zinc. The band, d, of the alkaline solution, is much more sharply defined and darker than y, and remains visible even when extremely dilute. Digitized by Microsoft® 62 ANALYSIS OF THE UBINE. To separate the pigment from tlie acid alcoholic solution it is mixed with about an equal volume of chloroform, and then shaken with a great excess of distilled water. The separated chloroform is washed once or twice with water, and as soon as the wash water begins to be colored the operation is stopped. After distilling off the chloroform, an amorphous resinous resi- due of a red color remains, which dissolves in alcohol, ether, and chloroform, first with a brownish-yellow color, which on dilu- tion becomes yellow and finally pale rose color. The solutions have a neutral reaction and show a considerable fluorescence. They give, examined with the spectroscope, the sharply de- fined band, S, like the alkaline solutions. C. Occurrence of Urobilin in Normal Urine. To detect it 100 to 200 cc. of urine are precipitated with basic acetate of lead, and the washed and dried precipitate is decomposed with alcohol containing oxalic acid. If this solution still shows no absorption bands it is treated with chloroform and shaken with water. The urobilin is thus obtained without the application of heat, which is to be avoided in concentrated solution, and free from those matters which by their absorbing action on the blue and violet part of the spectrum destroy the sharpness of the band. On the addition of ammonia and chloride of zinc the acid alcoholic solution shows exquisite fluorescence, and in the spectroscope gives the band, 6, with great sharpness. For the preparation of the pure pigment from normal urine, the washed and dried lead precipitate from a large amount of urine is boiled with alcohol several times, and then decomposed with absolute alcohol and sulphuric acid. The solution ob- tained is supersaturated with ammonia, the filtrate is diluted with about an equal volume of water, and then treated with chloride of zinc. A copious precipitate of a brownish-red color is produced, while the filtrate remains quite strongly colored, but always contains only a small amount of urobilin, though large amounts of other urinary pigments. The chloride of zinc precipitate is treated as given above, with fever urine. Jaffe further made the interesting observation that freshly passed, very pale urine, which showed no trace of an absorption band, on standing exposed to the air, often becomes darker, and then allows the dark and sharply defined characteristic band of urobilin to be recognized in the spectrum. Such urines show, Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, ORGANIC. 63 when the band, y, appears distinctly, after the addition of fixed alkalies, the band, 6, also, and ammonia and chloride of zinc oc- casion strongly marked fluorescence. Jaffe believes, therefore, that a chromogen of the urobilin is to be assumed to exist in the original urine, and has convinced himself, by direct experi- ments, that this becomes converted into urobilin with its char- acteristic qualities by absorbing oxygen. "We owe to Maly* an essential increase of our knowledge of the normal urinary pigment, urobilin. He succeeded in con- verting the red coloring matter of the bile, bilirubin, into uro- bilin, with all of its characteristic qualities, by the action of sodium amalgam. For this purpose pure bilirubin is suspended in water, and small pieces of solid sodium amalgam are added gradually. If, after a time, the alkaline solution of the bilirubin becomes clearer, an excess of the amalgam is added, and if, after from two to four days, with frequent shaking, and later, after gpntly heating on the water bath, it becomes no clearer, the change is complete. Hydrochloric acid precipitates the color- ing matter in the form of dark reddish-brown flakes from the fluid decanted from the mercury. The coloring matter, purified by repeated solution in alkalies, and precipitation with hydro- chloric acid, possesses all of the qualities of urobilin. Of these, we mention the following : 1. The urobilin, or, according to Maly, hydrobilirubin, pro- duced from bilirubin, does not give Gmelin's reaction for bile pigment. 2. The alkaline solutions vary in color from brown to the yel- low of normal urine. The acid solutions vary, according to the concentration, from garnet red to brownish red and pale rose color. 3. The spectral absorption between b and F in acid solutions, its paling in ammoniacal solutions, and the intense recurrence of a dark band removed somewhat to the left, sharply defined on the left, rather indistinct on the right, after the addition of - a small amount of a zinc salt to the ammoniacal solution. 4. The green fluorescence of the ammoniacal solution con- taining zinc, and its disappearance after the addition of an acid. 5. Its precipitation, by most of the metallic salts, in the form of brown or dark red flocculi. * Annal. der Chemie, Band 163, p. 77. Digitized by Microsoft® 64 ANALYSIS OF TEE URINE. In a similar manner biliverdin (the green pigment of bile) can be changed into urobilin by sodium amalgam. The circulation of these pigments is, therefore, apparent. Bilirubin and biliTerdin poured into the intestine with the bile, change, in their passage to the colon, by absorbing water and hydrogen, into urobilin, and, in fact, the coloring matter found in the contents of the intestine by Vaulair and Masius, sterco- bilin, is, according to the investigations of Jaffe,* identical with urobilin. Urobilin is absorbed from the intestine ; it can also easily be detected on the way from the intestine to the kidneys in the circulation; at all events, the spectroscopic test was com- pletely successful in the blood serum of the ox. When we consider, further, that blood corpuscles in solution injected into the veins always cause an icteric urine contain- ing bilirubin,t then the last link is no longer wanting which places in the clearest light the relations between hsemoglobiij, bilirubin, and urobilin.:]: Finally, Hoppe-Seyler § succeeded in producing a coloring matter by the action of tin and hydrochlo- ric acid on hsematin in alcoholic solution, which in all of its properties, chemical as well as optical, completely accorded with the urobilin of Jaffe as well as with the hydrobiliru- bin which Maly obtained by the action of sodium amalgam on bilirubin. Since now the same coloring matter is also pro- duced from undecomposed haemoglobin in alcoholic solution by tin and hydrochloric acid, there is no more doubt that the coloring matter of normal faeces and of the urine must be re- garded as a product of the decomposition by reduction of the blood pigment, and that the biliary coloring matters, biliru- bin and biliverdin, represent intermediate steps of this change, or at least stand in near relation to the blood pigment. II. TJEOCHBOM. (THTJDICHUM.) According to Thudichum, normal urine contains only one * 'Jahresbericlit d. Thierchemie, Band 1, p. 380. f Kiilme, Lehrbuch d. physiolog. Chemie, p. 89. I Hoppe-Seyler has witMn a short time given the proof that injections of water as well as of a solution of blood pigment into the jugular vein of dogs, resulted in a considerable increase of the amount of bile pigment in the bile. (Archiv d. Physiologie, Band 9, p. 339.) § Bericht d. deutsch. chem. Gesellschaft, Band 7, p. 1065. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. 65 yellow coloring matter, and the resin of Proufc, Scliarling's omichmyloxyd, Heller's urrhodin, Schunk's indigrubin, Sche- rer's urinary coloring matter, also the urohsematin of Harley, and the substance described by Marcet, are mixtures of the products of the decomposition of this yellow pigment, called urochrom by Thudichum. Maly's * investigations have demon- strated, however, that the so-called urochrom, like the coloring matters of Scherer, contain considerable quantities of urobilin. Thudichum t obtained his urochrom according to different methods, of which I give only one here, and in regard to the others refer to the original. Preparation. The urine is treated with baric hydrate till the reaction is alkaline (to one liter of urine about five grams of hydrate of barium), and then with a saturated solution of acetate of barium. After twelve hours the precipitate is filtered off, and the filtrate completely precipitated with acetate of lead and ammonia. The washed lead precipitate is triturated in a porcelain dish with dilute sulphuric acid, the excess of acid in the filtrate saturated with carbonate of barium without the aid of heat, the filtrate is made alkaline with baryta water and treated with carbonic acid. The filtrate is now precipitated with a solution of mercuric acetate, and the precipitate obtained washed with cold and hot water. The compound of mercury thus obtained must have a yellow color; if it is gray or dark colored the treatment with acetate of lead, etc., must be re- peated after decomposing it with sulphuretted hydrogen. The coloring matter is obtained by sulphuretted hydrogen in the form of a yellow solution from the urochrom-mercuric oxide made as pure as possible. This solution always contains in addition some hydrochloric or acetic acid. The hydrochloric acid can be removed by shaking with freshly precipitated oxide of silver, with which, however, a part of the urochrom combines to form a voluminous precipitate, while the fluid contains much acetate of silver. The yellow alkaline solution is finally freed from silver by sulphuretted hydrogen, and the filtrate, after evaporation on the water bath, leaves urochrom as an amor- phous, solid, yellow substance. * Annal. der Chemie, Band 163, p. 90. fBrit. Med. Journ., N. S. 201, p. 509, Nov. 5, 1864. Schmidt's Jahrbucher, 1865, Band 135, p. 154. 5 Digitized by Microsoft® 66 ANALYSIS OF THE URINE. Properties. Urocliroin forms yellow scales, which partially dissolve in water with a pure yellow color. It is difficultly soluble in alcohol, more easily in ether, very dilute mineral acids and alkalies. The aqueous solution becomes darker on standing, finally changing to a red color, becoming turbid and depositing resinous flocculi. Heat favors the decomposition, especially in the presence of acids. Sugar is not formed. Uro- chrom is precipitated from the aqueous solution by nitrate of silver as a gelatinous mass soluble in nitric acid ; acetate of lead gives a white flocculent precipitate. Basic acetate of lead and mercuric acetate produce a yellow precipitate. Mercuric nitrate gives a white precipitate, which on boiling becomes a pale flesh-color, while the supernatant fluid is colored rose red. By oxidation in the air there is first formed from the urochrom a red substance, which corresponds to uroerythrin, and to which- the red urine of disease owes its color. Under the in- fluence of acids, the yellow soluble, as well as the red substance, yields three insoluble products, which are deposited from an acid solution of urochrom after the addition of water, by suffi- ciently long boiling, in brown clumps which collect together in balls. On treating this deposit with alcohol, a brown powder soluble in potassic hydrate, from which it can be precipitated by acetic acid, uromelanin,* remains behind. The beautiful ruby-red alcoholic solution yields by precipitation with water a red resin, which can be decomposed by ether into two bodies. The ethereal solution has a very beautiful red color and con- tains a resinous acid, omicholic acid, corresponding to the omichmyloxide. A yellow substance remains behind insoluble in ether, uropittin, which is obtained in the crystalline form from absolute alcohol, and on analysis gives the formula €3H,„NA (C„H,„]Sr,Oe). Uropittin and uromelanin can also be obtained directly from the urine. Fresh urine is treated, drop by drop, with concen- trated sulphuric acid, and the filtrate evaporated in a retort to one-half. After cooling, a black resin separates, from which, after washing and drying, uropittin is extracted by alcohol, while uromelanin remains behind. According to Thudichum, the odor of decomposed acid or * Journ. f. pr. Chem., Band 104, p. 257. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. 67 alkaline urine comes from omicholic acid and uropittin, or the products of their decomposition; it is rendered stronger by carbonate of ammonium, but is not caused by it. The urine contains, moreover, a volatile ethereal oil, which is colored red by boiling with mercuric nitrate, and also cresyl alcohol. Urochrom, retained in the blood, is one of the characteristics of uraemia ; it is decomposed in the blood to uropittin and omicholic acid, which can be recognized again in the tissues, in the deposit on the teeth, and in the stinking breath. If the coloring matter is retained in the blood, the typhoid symptoms of uraemia predominate. Normal urine contains, according to Thudichum, no indican ; but this body and the products of its decomposition, with all of their characteristic properties, have been so frequently found in the urine by different investigators, that it may well be a question what is normal urine. m. UBOXANTHTN. (HELLBK. )— INDICAN. (SCHrNCK.) Heller calls a substance which occurs in normal urine in small amount, in diseased urine, however, in large amount, uroxan- thin. It imparts to the urine, when abundant, an intense light- yellow color, and possesses the noticeable property of yielding by the action of acids, etc., with the separation of a saccharine substance, two new pigments, uroglaucin and urrhodin. Ac- cording to the investigations of Schunck, Hoppe-Seyler and others, this body is nothing else than indican. Hoppe found it most abundantly in the urine in carcinoma of the liver, but it is also abundant in the urine of dogs. Oscar Wyss* detected considerable quantities of indican in the urine first passed after an attack of cholera. Jaffe t found a considerable increase of indican in the urine after subcutaneous injections of indol, a fact which is the more interesting, since, according to Kiihne's investigations, indol belongs to the products of pancreatic di- gestion in the alimentary canal, and M. Nencki | obtained it directly from blood albumen, in considerable quantity, by the action of pancreatic ferment. The greatest part of the indol, indeed, is passed off with the fasces, and imparts to them their * AtcMv der Heilkunde, Band 9, p. 382. f Centralblatt f. d. med. Wissenschaften, 1873, No. 1. X Bericlit der deutsch. chem. Gesellsohaft, Band 8, p. 336. Digitized by Microsoft® 68 ANALTSIS OF THE UBINE. characteristic odor ; another part is absorbed, and uniting with a saccharine substance, is eliminated with the urine as indican. If the separation with the excrement is impeded, a greater re- sorption may be expected, and, in fact, Jaffe found, in a fatal case of incarceration of the small intestine, enormous amounts of indican in the urine. Eosenstein* found a considerable increase of indican in Ad- dison's disease, and Jaffe t found it in all diseased processes which cause obstruction of the small intestine. This mother substance of indigo is decomposed very readily in contact with sulphuric acid, hydrochloric acid, etc. The coloring matters, indigo blue, indigo red, etc., separate, while a saccharine substance which reduces the oxide of copper, indig- glucin, OsHijOs [OisHnOij], leucin, and volatile fatty acids (acetic acid, formic acid, etc.) remain in solution. The same decom- position is brought about by ferments, especially by the decomposition of the urine ; indigo white is formed, which becomes blue when exposed to the air, hence putrefying urine frequently shows a bluish-red, metallic, shining pellicle on the surface. Indican is precipitated from its solution by an ammoniacal solution of acetate of lead. Preparation. Fresh urine is precipitated with basic acetate of lead, filtered and precipitated with ammonia. The second pre- cipitate is filtered off, washed, suspended in alcohol, and de- composed by sulphuretted hydrogen. The filtrate is then first evaporated at a gentle heat, and finally over sulphuric acid in a vacuum. The indican thus obtained is still rendered some- what impure by sugar. For its further purification it is dis- solved in water, shaken with freshly precipitated hydrated oxide of copper, filtered, the filtrate treated with sulphuretted hydrogen, precipitated with ether, and the fluid filtered off and evaporated best in a vacuum. The indican thus remains behind as a clear brown syrup. (Hoppe-Seyler.) IT. UKOGLAUCIN AND TTKEHODIN. — INDIGO BLUE AND INDIGO RED. These substances sometimes occur in the sediment of patho- * Vircliow's Archiv, Band 56, p. 27. f Centralblatt f. d. med. Wissenschaft. , 1872, No. 31. Digitized by Microsoft® NOBMAL CONSTITUENTS OF URINE, OBGANIC. 69 logical urine. They are, as above remarked, according to Heller, the products of the oxidation of uroxanthin, according to Schunk they are most probably the products of the decom- position of indican. a. Urrhodin (indigo red). The ethereal solution after evapo- ration leaves the pigment behind in a solid form, but non-crys- talline. Indistinct crystals are obtained, however, on very slow evaporation of an alcoholic solution. Urrhodin appears crys- tallized almost black or in very thin layers carmine red. It appears in the form of rose-red granules when amorphous. It dissolves in alcohol and ether with a beautiful red color, but is insoluble in water.* After the ingestion of oxindol and dioxindol, these bodies do not appear again in the urine of men, dogs or rabbits. Yet when the urine was heated with hydrochloric acid and ex- tracted with alcohol and ether, red coloring matters were con- stantly obtained in small quantity, which had a resemblance to those which are obtained by the oxidation of aqueous solutions of oxindol and dioxindol in the air. (M. Nencki and Massow.) After the internal use of isatin, however, a pigment is obtained both from dog and human urine, which corresponded with a pigment, which Nencki t obtained from the urine of a woman suffering from paralysis of the cervical part of the spinal cord, and which appears to be identical with indigo red (urrhodin). b. Uroglaucin (indigo blue). Uroglaucin appears as a blue powder which consists of microscopic needles terminating in a fine point, but which seldom occur isolated, being usually col- lected together in groups of two, three, or several. They fre- quently form star or circular-shaped groups, which are again joined together and present large clumps of radiating bodies. Indigo blue is capable of sublimation, a^jd can be reduced by sulphate of iron, etc. It is often found in the urine in degene- ration of the kidney, and at times, according to Virchow, in the crystalline form. In putrefying urine it occurs as a product of the decomposition of indican. Such a urine frequently becomes blue on shaking with air, and on standing a blue iridescent pellicle forms on the surface, in which, at times, microscopic * Heller's Archiv, 1846, p. 31. f Berichte d. deutsch. ctem. Gcsellscliaft, Band 7, p. 1593. Digitized by Microsoft® 70 ANALYSIS OF THE URINE. needles of indigo can be recognized. (Hoppe-Seyler.) The ad- dition of hydrochloric or nitric acid frequently separates it from the urine mixed with uric acid as a precipitate, which is gradu- ally deposited. These products of the decomposition of indican can be obtained from the urine by different methods. A. Frejjaration by the method of Schunck. The urine is treated with basic acetate of lead as long as a precipitate occurs, filtered, and the filtrate precipitated with an excess of ammonia, by which the indican (uroxanthin) is precipitated in combina- tion with oxide of lead. The precipitate, collected and washed, is decomposed completely by cold dilute hydrochloric or sul- phuric acid, and the solution is filtered. If there is much indigo- forming material present, the filter and precipitate, and also the surface of the brown filtrate, are colored with a blue sub- stance ; if there is but little present, the blue pellicle is formed only after twenty-four or forty-eight hours on the filter, never later. The brown filtrate, after removal of the indigo blue, which gradually separates, deposits on boiling a dark brown powder, which has the same appearance as that which can be obtained directly from the extractive matter of the urine by boiling it with acids, and which partly dissolves in sodic hydrate with a brown color and partly remains undissolved. The undissolved portion is separated iato two bodies by boil- ing alcohol, one of which dissolves in it with a purple-blue color, and appears to be identical with indigo red, the other has the characteristics of indigo blue.* B. Preparation by the method of Kletzinsky and Keller. Urine, which is colored blue by mixing with fuming hydro- chloric acid, is completely precipitated by basic acetate of lead, and the filtrate, freed from the excess of oxide of lead by sul- phuretted hydrogen, is evaporated to one-third. The fluid, while still warm, is allowed to flow into two or three times its volume of fuming hydrochloric acid, and allowed to stand a few days, during which time a thin, coppery-red, iridescent pellicle forms on the surface of the mixture, and the fluid gradually becomes cloudy. It is filtered, the bluish-black mass which is separated is washed completely with water, and treated with ether after * Journ. f. pr. Chem., Band 75, p. 378. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. 71 drying over sulphuric acid; the ether becomes dark red or purple, and contains a red, amorphous, resinous mass, urrhodin (iadigrubin, according to Schunck). The residue left by the ether is then boiled with alcohol, and the deep bottle-blue solution is left to itself in closed flasks. After some months a velvet-black sediment has deposited, which frequently contains rudimentary crystals (the elementary analysis of this precipi- tate corresponds, according to Kletzinsky, with that of indigo blue). In urine which is very rich in indican there is no need, according to my experience, of this detailed manipulation ; such a urine, on mixing an equal volume of hydrochloric acid, very soon deposits the pigments. The amount obtained is always very small, and with less than ten to twenty pounds of urine the work should not be undertaken. C. Detection. — 1. The following very pretty reaction of Heller serves for the detection of even small amounts of indican. Three to four cc. of strong faming hydrochloric acid are mixed in a test tube with thirty or forty drops of the urine to be tested, or the urine, after the addition of a little hydrochloric or nitric acid, is heated to boiling. If indican is present the mixture is colored from a reddish violet to intense blue by the decomposi- tion of this body. If with small amounts of indican the reaction fails, it can be made far more delicate by the addition, of two or three drops of strong nitric acid. There results from this refinement of the test, not immediately but in a few minutes, a beautiful violet color, which first plays rather into blue, but later rather into red, and sooner or later becomes dirty red, and at last yellow again. The color appears almost always with- out the addition of nitric acid, but the latter enables us to de- tect the least traces of indican. Indican suffers in this reaction as in the others a decomposition into indigo blue, indigo red, and sugar. 2. Ten cc. of the urine to be tested for indican are treated with an equal volume of hydrochloric acid, and then a saturated solution of calcic hypochlorite is added drop by drop. The mixture becomes, according to the amount of indican present, red, violet, green, or blue, but after filtering, under all circum- stances, it leaves behind on the filter a distinct blue tinge. (Jaffe'.)* * ArcMv der Physiolog., Band 3, p. 448. Digitized by Microsoft® 72 ANALYSIS OF THE URINE. 3. According to Stockvis the urine to be tested should be warmed with two parts of impure nitric acid to 60° or 70° and shaken with chloroform or ether. Both solutions are then quickly colored violet blue, and show, when placed before the slit of the spectroscope, the characteristic absorption bands of indigo blue between C and D. The solutions of sulphindigotic acid give, on spectroscopic examination, a sharp, dark absorption band between the lines and D, which reaches beyond D when the solution is more concentrated. I have had an opportunity here to observe a urine very rich in indican, for a long period. It was secreted at different times, and for a long period uninterruptedly by a young man eighteen to twenty years of age of apparently healthy constitution. This urine, treated with about an equal amount of hydro- chloric or nitric acid, soon became violet, then darker, and at last a deep, dark blue. After shaking and standing awhile the pigment separated either as a deep blue scum or as a thin, red- dish-blue, iridescent pellicle. The washed coloring matter consisted of a deep blue powder with. a copper-red streak, which dissolved in boiling alcohol, but on cooling separated, for the most part, again, while the supernatant fluid remained colored violet or reddish (urrhodin). The product thus obtained could be sublimed at a moderate heat, when it first gave rise to beautiful red fumes, and then was deposited as a reddish-brown sublimate. Seen under the microscope it shows the above-mentioned groups of needles. This sublimate could not be distinguished from sublimed in- digo, and also its behavior to concentrated sulphuric acid, nitric acid, and especially reducing agents, such as ferrous oxide, sul- phide of ammonium, etc., completely corresponded with that of indigo.* The pigment was entirely destroyed by evaporating the urine, so that it was no longer capable of demonstration in the resi- due. Nitrous acid destroyed it also. It remains for me to call attention to a peculiar behavior of this urine toward concentrated sulphuric acid : if a small amount of it was treated with a sixth or a fourth of its volume of con- * Annal. d. Chem. u. Pharm., Band 90, p. 130. Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, OBOANIG. 73 centrated sulphuric acid, without mixing, there occurred, first, at the point of contact of the two fluids, a red coloration, which always became darker, the color finally spread through the whole mass, and the fluid became a deep, dark red, which changed to a purple violet. This play of colors was perfectly similar to that which jaundiced urine yields on treating with sugar and sulphuric acid ; yet here the color appeared without the addition of sugar, and failed to appear when the pigment was decomposed by evaporation. Although indican occurs very frequently in normal urine, at least in small amount, yet it is not ijnprobable that it can be increased, in certain diseases, so as to form a symptom of the disease, and, therefore, it well deserves the attention of physi- cians. At all events it is of great interest to recognize indican, that is, indigo blue, etc., as a probable product of the decom- position of protein matters, which is rendered more likely by the fact that the products of decomposition of indican include among others, as above remarked, in addition to a saccharine substance, both leucin and volatile fatty acids. Relatively very large amounts of indigo are obtained from the urine of the horse and cow. Creasote and oil of bitter almonds, even taken in small doses, are said to increase the amount of indigo in the urine very much. (Kletzinsky.) It is readily seen that by the combination of urobilin with varying amounts of urrhodin and uroglaucin, very manifold shades of color in the urine (greenish, grass green, violet, red- dish) can result. V. TJEOBRTTHEIN. That coloring matter is called uroerythrin which imparts to sediments of uric acid and urates their brick-red or rose-red color, and which, on contact with the air, increases considerably. Uroi'rythrin is said also to occur in solution in pathological urine, to which it imparts a red color. According to Thudi- chum, it probably is the result of the oxidation of normal urochrom. The red sediments which occur so frequently appear, how- ever, to contain at least two different pigments, since according to Hoppe many sediments yield to chloroform a beautiful pur- Digitized by Microsoft® 74 ANALT8I8 OF THE UMNB. plish-red pigment soluble in alcohol, while according to Heller uroerythrin is insoluble in alcohol. According to Heller, alco- hol only extracts from the sediments urrhodin (indigo red) and uroglaucin (indigo). According to Jaffe, urobilin (see above) is not identical with the pigment of these sediments. Even if in many sediments urobilin undoubtedly occurs, it appears to be completely wanting in others, or to exist in common with one or several other pigments by which its entire demeanor is altered. VI. BLACK UEINE. J. Vogel found a dark-colored urine after breathing arseni- uretted hydrogen. "Waldenstrom, Almen, Salkowski, Bartels,* and others observed after inunctions of tar, but especially after the external as well as internal use of carbolic acid, tarry-look- ing, almost black urine. According to Waldenstrom, Salkowski, and Almen, t carbolic acid can be detected in the urine in the latter case. Maly X did not succeed, however, in such cases in detecting phenol in the distillate. The dark color spoken of does not seem to occur in the bladder, but first appears on exposure to the air. According to the observations of Maly, the brown- ing or blackening first appears as a zone in the upper layer of fluid, which gradually descends from above downward, when the urine remains at rest. § 11. Keyptophanic Acid. According to the investigations of Thudichum,§ kryptophanic acid discovered by him is the normal free acid of the urine. (?) It forms the chief mass of the so-called extractive matter, and is obtained from normal urine in the following manner : The urine is made alkaline with milk of line, filtered, evapo- rated, then acidulated with acetic acid and concentrated until the salts, etc., crystallize out. The syrup decanted from the * Oral communication, f Neues Jahrb. f. Pharm., Band 34, p. 113. :[: Jahresbeiiclit u. d. Fortsohritte der TMerchemie, 1871, p. 184 § Centralbl. f. d. med. Wi,ssenschaft.,1870, p. 195 and 309'. Zeitschr. f. analyt Chemie, Bamd 10, Heft 1 . ' Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, ORGANIC. 75 crystals is shaken in a flask with five times its Yolume of 90 per cent, alcohol, when impure krytophanate of calcium sepa- rates, which is repeatedly washed with alcohol. To purify it, the crude calcium salt is dissolved in water, and precipitated with a large excess of a saturated solution of acetate of lead. It is filtered and five or six times its volume of strong alcohol is added to the filtrate, by which white neutral krytophanate of lead is precipitated. The precipitate is collected on a filter, washed with alcohol, then with a little water, and lastly with ether ; it is dried in a vacuum and finally decomposed with a sufficient amount of sulphuric acid. For its further purifica- tion the acid is saturated with baryta water, the excess of ba- rium is removed by carbonic acid, the krytophanate of barium precipitated with alcohol, again dissolved in water and once more precipitated with acetate of lead in excess. The filtrate which now results yields, after the addition of alcohol, pure, white, neutral krytophanate of lead. To obtain the free acid the lead salt is decomposed with sulphuric acid. The product thus obtained is amorphous, gummy, transpa- rent, soluble in water, less so in alcohol, and least in ether. Thudichum attributes to his new, long-hidden acid a great physiological as well as pathological significance, but further investigations must yet decide whether this is really a pure substance, which from the mode of preparation is somewhat doubtful. J. Pircher* and A. Silversidget could not convince them- selves of the existence of kryptophanic acid. Both investiga- tors arrived at no decisive result. Hlasiwetz and Habermann, J however, suppose that Thudichum's kryptophanic acid is only an impure glutamic acid, which also, like kryptophanic acid, reduces cupric oxide in alkaline solution, and whose formula (^;5Hg]Sra4) corresponds with that of kryptophanic acid (t^ Ji,NO.,) within one atom of oxygen. Further investigations upon this substance are, therefore, very much to be desired ; certainly the occurrence in the urine of glutamic acid, an interesting pro- duct of the decomposition of animal as well as vegetable albu- minoid bodies, would be of great physiological interest. * Centralblatt f. d. med. Wissenschaft.,1871, No. 4. f Joum. of Anat. and Physiol., vol. vi., p. 432. t Annal. d. Chem. u. Pharm., Band 159, p. 150. ' Digitized by Microsoft® 76 ANALYSIS OF THE UBINB. B. Inorganic. §12. The urine contains of tlie inorganic bases especially sodium, potassium, calcium, and magnesium, partly combined, espe- cially the first two, with uric and hippuric acids, but also with sulphuric, phosphoric, hydrochloric, and nitric acids. Besides these, small amounts of iron and silicic acid, finally also am- monium salts, especially in alkaline urine. The urine does not contain free gases except carbonic acid, nitrogen, and traces of oxygen ; pathologically, however, sulphuretted hydrogen some- times occurs. The whole amount of non-Tolatile salts con- tained in the urine differs in different persons and under dif- ferent pathological conditions very much. Thus in men varia- tions of from 9 '06 to 24'50 grams occur, in women from 10"28 to 19 "63 grams. Lehmann found in his own urine daily, while on a mixed diet, 15"245 grams (varying between 9'652 and 17"284: grams).* § 13. Ohlobide op Sodium. A. Presence. We may assume that almost all of the chlorine occurring in urine is in combination with sodium. The amount of chloride of sodium secreted varies in different persons and at different times of the day. Hegar has communicated observations on the variations in the amount of chloride of sodium in eight persons, the results of which are briefly as follows : On an average the chlorine separated in twenty-four hours amounted to 10*46 grams, cor- responding to 17*5 grams of chloride of sodium. The secre- tion of chlorine is the greatest in the afternoon ; at night, how- ever, it diminishes considerably and rises again in the morning. Physical exercise increases, and slight disturbance of the health diminishes the secretion quite rapidly. The amount is rapidly * E. Weidner. Investigations of normal and pathological urine, especially in regard to the proportion of lime, magnesia, potassium, sodium and iron to the other constituents of the urine. Rostock bei Adler's Erben, 1867. E. Salkow- ski, investigations concerning the secretion of the alkaline salts. Virohow's Archiv, Band 53, p. 203. Digitized by Microsoft® JSrOMMAL CONSTITUENTS OF URINE, INORGANIC. 77 increased by drinking water, but it diminishes later so mucli the more. After taking beer the ainount of chlorine is unusually small. With regard to the whole amount of chloride of sodium separated in twenty-four hours, the observations of Bischoff* differ somewhat from the statement of Hegar. He found in his own urine, in twenty-four hours, between 8 '64 and 2448 grams, and gives as the average 14'73 grams. The amount of cloride of sodium is extraordinarily diminished in many diseases, indeed, in all in which abundant exudations take place from the blood. Kedtenbacher saw in inflammations of the lungs the amount of chlorine often diminished to a mini- mum, so that in some cases no cloudiness at all could be ob- served after adding nitrate of silver. B. Mici-oscapic Properties. Chloride of sodium crystallizes under the microscope in extraordinarily beautiful, regular, stair-like cubes. It suffers a peculiar modification when it crystallizes from a solution which contains urea at the same time ; the ordinary cubes are thereby changed into octahedral and tetrahedral forms. C. Chemical Properties. — 1. If water is poured over pure, coarsely crushed, crystalline rock-salt, and the fluid, after a thorough shaking, is allowed to stand twenty-four hours at 12° to 50° 0., an invariable amount of salt is dissolved. In 10 cc. of this clear filtered solution Liebig and others found, as an average of many very nearly coinciding estimations, 3-184 grams of common salt. 2. Nitrate of silver produces, in all fluids which contain chlo- ride of sodium, a white caseous precipitate of chloride of silver, insoluble in nitric and hydrochloric acids. If the urine, how- ever after it has been acidulated with nitric acid, is treated with a solution of nitrate of silver, the precipitate which results is never pure chloride of silver, but the pigments, uric acid, etc., are also precipitated by the silver salt, and m the quantitative estimation of chlorine by nitrate of silver this is not to be disregarded. _ . 3 If a concentrated solution of chloride of sodium is mixed with a concentrated solution of mercuric nitrate, the two salts quickly undergo mutual decomposition, nitrate , of sodium is « BiscliofE, Urea, 1853, p. 33. Digitized by Microsoft® 78 ANALYSIS OF TEE URINE. formed, and the fluid solidifies to a crystalline mass of corrosive sublimate. The same decomposition takes place in dilute solu- tions also, only the corrosive sublimate formed does not sepa- rate, but remains in solution in the fluid. We have seen under urea, that in a solution of this sub- stance, which is feebly acid or neutral, mercuric nitrate pro- duces a precipitate of urea with mercuric oxide. Corrosive sublimate, on the contrary, produces no precipitate in acid or neutral solutions of urea. After this premise it will be easy to understand the following reaction, which Liebig has made use of for the quantitative estimation of chloride of sodium in the urine. If the phosphoric and sulphuric acids are removed from specimens of urine by the addition of nitrate and hydrate of barium, and if the alkaline filtrate is made neutral again or feebly acid by nitric acid, the fluid is a weak acid solution of chloride of sodium with urea. If now we treat this with a dilute solution of mercuric nitrate, drop by drop, a white pre- cipitate will occur at the point of contact of the two fluids, which, however, disappears again on stirring the mixture. The precipitate which first takes place is the compound of urea- mercuric oxide. But, since chloride of sodium is in the fluid, the mercuric nitrate is immediately changed to corrosive subli- mate, which, as is known, does not precipitate urea in feebly acid solutions. Therefore, the precipitate which first occurs disappears, and the fluid becomes as clear as before. This play of reactions is repeated in the same way until all of the chlo- ride of sodium present has been used up in changing the mercuric nitrate into corrosive sublimate. At last it ceases, another drop of the mercuric nitrate solution finds no more chloride of sodium by which it can be changed into corrosive sublimate, and a permanent precipitate of urea-mercuric oxide is produced. If the amount of the mercuric nitrate solution which has been added up to this point is known, the amount of chloride of sodium which was present can be readily reck- oned, since one equivalent of mercuric oxide corresponds to just one equivalent of chloride of sodium. 4. If a neutral solution of chloride of sodium, which at the same time contains phosphate of sodium, is treated with a few drops of a neutral solution of chromate of potassium, and a solution of nitrate of silver is allowed to flow into it, drop by drop, from Digitized by Microsoft® NOBMAL CONSTITUENTS OF URINE, INOBGANIG. 79- a pipette, all of the chlorine will be first precipitated as chlo- ride of sUver. When this point has been reached, the next drop of the silver solution gives a permanent red color, due to chromate of silver. The phosphoric acid remains completely in solution up to this point, since the silver salt precipitates these three acids in the following succession : chlorine, chromic acid, phosphoric acid. (Mohr's volumetric method.) D. Detection. The reaction with nitrate of silver already given always serves for the recognition of chloride of sodium in the urine. But the urine contains phosphoric acid, and this also gives, with oxide of silver, a precipitate of phosphate of silver, which, however, is soluble in nitric acid, while chloride of silver is not soluble in this reagent. We must, therefore, in testing urine for chlorine, add to it, either before or after the addition of the silver solution, nitric acid enough to give a strong acid reaction. In the first case the phosphate of silver will not then be precipitated, but in the second it will dissolve again directly, and only the choride of silver remains in caseous flakes. If the urine is evaporated to a syrupy consistence, the chlo- ride of sodium crystallizes out after a time in cubes or octa- hedra, which can easily be recognized. The spectroscopic test, obtaining the yellow sodium flame, serves for the direct recog- nition of the sodium. § 14. Chloeide of Potassium. The urine, together with chloride of sodium, contains chlo- ride of potassium, which has the same crystalline form as chlo- ride of sodium. To detect the potassium in urine it is treated with a little hydrochloric acid, an equal volume of a mixture of alcohol and ether is added, and afterward a solution of chlo- ride of platinum. After a few hours the potassio-platinic chloride, mixed with ammonio-platinic chloride, will have sep- arated in beautiful octahedra, which are readily recognizable under the microscope. Tartaric acid can also be used with advantage. 100 to 150 cc. are evaporated to one-eighth of the original volume, allowed to cool, filtered, and the filtrate treated with a concentrated solution of tartaric acid in excess. After standing ten hours in Digitized by Microsoft® go ANALYSIS OF TEE UBINE. a cool place the separation of acid tartrate of potassium is com- plete. Salkowski * obtained by this method from 500 cc. of urine 2 "7 to 3 grams of cream of tartar. "Weidner t found in his own urine, on an average, 3-91 grams of potassium in twenty-four hours. The maximum amounted to 5-9 grams, the minimum 2 grams. The relative proportion of potassium and sodium was 1 : 1'35. % § 15. Sulphates. A. Presence. Many experiments have been undertaken, under the direction of Vogel, concerning the amount of sulphates in the urine. From these determinations it has been proved that an adult passes, on an average, 2-094 grams of sulphuric acid in twenty-four hours, which coincides with the more recent inves- tigations of "Weidner, who found on the average 2-1 grams. During the time of digestion the amount of sulphuric acid secreted increases, it sinks somewhat in the night, and reaches its minimum in the forenoon hours. The secretion increases for a short time on copious drinking of water, but later decreases all the more. (Gruner.) Sulphates taken into the economy are completely separated again with the urine in from eighteen to twenty-four hours. Pure sulphur also increases the amount of sulphuric acid in the urine. Without doubt the sulphur of the protein substances ingested with the food is gradually oxidized to sulphuric acid in the blood, and is then eliminated with the urine, combined with alkalies. Therefore, after an abundant meat diet, not only the urea, but also the sulphuric acid is found increased in the urine. Disease, also, frequently exercises a decided influence on the excretion of sulphuric acid, so that it is often increased and often diminished. B. Chemical Properties. Some of the sulphates are soluble in water, and some insoluble. The sulphates of the alkalies and alkaline earths are not decomposed by a red heat ; if, however, they are heated with charcoal or organic matters which yield charcoal on being heated, they undergo a reduction to free sul- * Archiv d. Physiologic, Band 2, Heft 351. f Loc. cit. X Investigations of the secretion of alkaline salts by E. Salkowski, Virchow's ArcMv, Band 53. Digitized by Microsoft® NOBMAL CONSTITUENTS OF URINE, INORGANIC. 81 phur, which can be recognized by the odor of sulphuretted hy- drogen, if the red-hot mass is moistened with a little acid. If this test is made on polished silver a black spot is produced. 1. Chloride of barium produces, in solutions of the sulphates, a white, fine pulverulent precipitate of sulphate of barium, in- soluble in nitric and hydrochloric acids. 2. Acetate of lead precipitaites sulphate of lead, 3. If organic matter and sulphates are moistened and exposed to a tolerably high temperature, sulphuretted hydrogen is formed. It is possible that the sulphuretted hydrogen, at times occurring in the urine, is formed in this manner. C. Detection. Sulphuric acid gives, with barium salts, a pre- cipitate insoluble in acids, and apparent, even when very dilute ; in testing a urine for sulphuric acid, therefore, we make it strongly acid with nitric or hydrochloric acids, for the reasons given under chloride of sodium, and then treat it with a solu- tion of chloride or nitrate of barium; any precipitate which takes place (sulphate of barium) points with certainty to the presence of sulphuric acid. § 16. Acid Phosphate op Sodium. A. Presence. This salt, according to Liebig's investigations, without doubt occurs in the urine, and is also in most cases the chief cause of its acid reaction. Many determinations of the amount of phosphoric acid in the urine have been made by Breed.* The average excretion of phosphoric acid in twenty-four hours in a number of per- sons was from 3"765 grams to 5-180 grams. This daily amount of phosphoric acid, however, appears to me to be somewhat too high according to the numerous determinations given in recent times, which is to be attributed to the very defective method of determination with ferric chloride, which has hither- to been used. According to the volumetric method with oxide of uranium solution, first proposed by me for the determination of the phosphoric acid in the urine, I have seldom found more than two grams of phosphoric acid in twenty-four hours under normal conditions. Weidner found the maximum was 3 "8, the *Ann. d. Chem. u. Pharm., Band 78, p. 150. 6 Digitized by Microsoft® 82 ANALYSIS OF THE URINE. minimum 2-25, and the average 2-76 grams. Increased drink- ing augments the secretion a little, yet, according to Winter, only during the first three or four hours. Winter also found that at night considerably more phosphoric acid is secreted than in the morning, but most of all at midday, and both Winter and Breed observed that the amount of phosphoric acid very considerably increased after taking food. The variations in disease are tolerably great, as is readily understood ; accord- ing to Heller, it should keep tolerable pace with the sulphates.* B. Chemical Properties. — 1. The acid phosphate of sodium is readily soluble in water and gives to it an acid reaction. On heating it to a red heat alone it is not decomposed, but if it is at first very intimately mixed with charcoal, or ignited with organic matters, a part of the phosphoric acid is reduced, and phosphorus is formed which is immediately volatilized. 2. Chloride and nitrate of barium give in solutions of phos- phate of sodium a precipitate of phosphate of barium, which is readily soluble in acids. 3. Phosphoric acid forms compounds with calcium and mag- nesium which are insoluble in water, but are soluble even in acetic acid without decomposition. In the urine we find phosphate of calcium and phosphate of magnesium, which are held in solution by the free acids or acid salts. If we neutralize the urine with ammonia, the phosphate of calcium is precipi- tated unchanged, the phosphate of magnesium, however, takes Tip ammonium and appears as ammonio-magnesian phosphate in the precipitate. The formation of these compounds, which occur in alkaline urine as a sediment, depends on this. The alkaline reaction of a urine comes mostly from carbonate of ammonium produced by the decomposition of urea ; but as soon as this has formed the free acid of the urine disappears, and the earthy phosphates can no longer be held in solution. The phosphate of calcium then separates usually in the amorphous form, but the phosphate of magnesium separates in beautiful crystals as ammonio-magne- sian phosphate. 4. Ferric chloride gives, in solutions of the phosphates which are acidulated with free acetic acid, a yellowish-white, gela- * See Weidner, loc. cit. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE. INORGANIC. 83 tinous precipitate of phosphate of iron. This compound is soluble in all acids except acetic, therefore a solution from which we wish to pecipitate the phosphoric acid by ferric chloride must contain no other free acid. If, however, any other free acid is present, acetate of sodium and free acetic acid are added to the fluid before the precipitation with ferric chlo- ride ; in this way the solution is rendered acid with acetic acid, in which the phosphate of iron is insoluble. 5. If a phosphate is dissolved in water or acetic acid and treated with acetate or nitrate of uranium, a yellow precipitate of phosphate of uranium immediately takes place. The pre- cipitate does not dissolve in water and acetic acid, but does in the mineral acids, from which it may again be completely pre- cipitated by a sufficient excess of alkaline acetates and heat. We make use of this reaction for the volumetric estimation of phosphoric acid. C. Detection. (See § 17.) § 17. Phosphates of Calcium: and Magnesium. As above remarked, these two earthy phosphates are in solu- tion in acid urine, but they are separated from it as soon as it is rendered alkaline. A long series of observations, which I commenced on the secretion of the earthy phosphates in four healthy young men, gave the following results : 1. In the normal condition there was passed by an adult male from twenty to twenty-five years of age, on a mixed diet, in twenty-four hours, as a mean of fifty-two observations, 0.9441 to 1*012 grams of earthy phosphates. The maximum amounted on the average to from 1'138 to 1"263 grams ; only once was 1-554 grams passed in twenty-four hours. The minimum amounted to an average of 0"8 gram, and once only 0-328 gram was passed. 2. The phosphate of calcium amounted on an average of fifty- two estimates to from 0-31 to 0-37 gram. The maximum aver- aged 0-39 to 0-52 gram ; only once was 0-616 gram passed. The minimum was tolerably' constant at 0-25 gram ; once only it amounted to 0-15 gram. 8. The phosphate of magnesium amounted on an average Digitized by Microsoft® 84 ANALYSIS OF TEE UHmj. of fifty-two observations to 0*64 gram. The maximum aver- aged 0'77 ; only once 0-938 gram was passed. The minimum amounted in the average to 0'5, but sank once to 0"178 gram. , 4. In the normal condition on the average about one equiva- lent of 3CaO,P05 to three equivalents of 2MgO,P05 is passed. In one hundred parts of earthy phosphates 67 per cent, consist of phosphate of magnesium, and 33 per cent, of phosphate of calcium. 5. Calcium salts ingested do not pass out in the urine, or only in very small amount ; the whole amount of phosphates secreted normally does not thereby suffer any very great in- crease. 6. In disease the absolute amount of earthy phosphates, as well as the relative proportion between calcic and magnesia phosphates, departs much from the normal secretion. Detection. The recognition of phosphoric acid in acid urine presents no difficulties ; the precipitate which takes place im- mediately upon the addition of ammonia, and consists of earthy phosphates, leaves no doubt of its presence. " It can readily be determined if the urine contains any more phosphoric acid than was precipitated with the calcium and magnesium, by filtering off the ammonia precipitate, and testing the filtrate acidified with acetic acid with uranium solution ; the formation of a yellowish-white precipitate will show the amount of the phosphoric acid which remains. In an alkaline urine we find the earthy phosphates in the sediment, and will refer to them under that head. If we wish to separate the calcium from the magnesium in the precipitate which takes place on the addition of ammonia, and which consists of the phosphate of calcium and ammonio-magnesian phosphate, we dissolve the precipitate in acetic acid, add a little chloride of ammonium, and then a solu- tion of oxalate of ammonium, by which the calcium is precipi- tated as oxalate, while the magnesium remains in solution, and can be precipitated from the filtrate by the addition of ammonia again as ammonio-magnesian phosphate. § 18. Ikon. A. Presence. Iron for the most part is found only in very minute quantity in the residue of urine after ignition. If a Digitized by Microsoft® NORMAL CONSTITUENTS OF UBINE, INOSGANIG. 85 urine contains blood, iron is more easily detected in the ash. According to the inYestigations of Magnier * the amount of iron in a healthy man of medium weight varies between 0-003 and 0-011 gram in a liter. A mean of fourteen examinations gave 0-007 gram of iron to the liter of urine. B. Chemical Properties. ■ 1. Sulphide of ammonium yields in ferrous and ferric solu- tions a black precipitate of sulphide of iron, which is readily soluble in hydrochloric and nitric acids. 2. Ferrocyanide of potassium yields in ferric solutions a deep blue precipitate of ferrocyanide of iron (Prussian blue). In ferrous solutions the precipitate is bluish white, and consists of ferricyanide of potassium and iron. 3. Sulphocyanide of potassium does not change ferrous solu- tions, but it produces the intensely red sulphocyanide of iron in ferric solutions. 4. If a solution of permanganate of potassium is added to an acid solution of a ferrous salt, the ferrous oxide becomes con- verted into ferric oxide, and when this point is reached, the next drop of the permanganate of potassium solution causes a beautiful red coloration of the fluid. 0. Detection. The ash of the residue of urine is always chosen for the isolation and detection of iron. It is dissolved in a little hydrochloric acid, and the solution divided into two parts. The first half is boiled with a drop of nitric acid and treated with sulphocyanide of potassium ; if there is the least amount of ferric oxide present, the fluid will assume a reddish color, which becomes a deep dark red when it is in greater amount. With mere traces of ferric oxide, the color is seen most distinctly when the test tube is placed on a white surface and examined from above. If, instead of sulphocyanide of potassium, ferrocyanide of potassium is added to the second portion after boiling with nitric acid and diluting, flocculi of Prussian blue separate after standing a time. If the amount of iron is more considerable the Prussian blue is immediately precipitated. *Berichte d. deutsch. chem. Gesellschaft, Band 7, p. 1796. Digitized by. Microsoft® 86 analysis of the umine. § 19. Ammonium Salts. It is a well-known fact that the detection and estimation of the ammonium salts in normal urine is attended with many difficulties. The readiness with which the coloring and extrac- tive matters decompose, and the urea becomes converted into carbonate of ammonium, especially if the above matters are present, is well known. This is the reason that we continually find different statements concerning the occurrence and amount of the ammonium salts in normal urine. If normal acid urine is concentrated in a retort at as low a temperature as possible, ammonia will always be found in the distillate, while the con- centrated urine which remains behind often reddens litmus stronger than before. This surprising appearance is explica- ble in the following manner : The acid phosphate of sodium present in the urine decomposes the urea on the application of heat, and ammonio-sodic phosphate is formed. But this sp-lt has the property of giving up its ammonia at a temperature of 100", and changing again to acid phosphate of sodium ; the acid phosphate of sodium, therefore, acts destructively on the urea as long as the evaporation lasts, and the urine can, there- fore, always retain its acid reaction while a large amount of ammonia is in the distillate. With some care, however, it is possible to detect with the greatest certainty small amounts of ammonium salts in normal urine, and the labors of Heintz, Boussingault, and myself re- move all doubt on this point. O. Schultzen and L. Eiess found trimethylamin also in the urine in acute atrophy of the liver. C. M. Tidy and W. B. Woodmann* have carried out thorough investigations with regard to the amount of ammonia in the urine in health and disease. These authors give as the normal average 0162 gram of NHs in twenty-four hours. They ob- served a diminution to one-half in acute articular rheumatism, in albuminuria, phthisis, and nervous diseases. The normal amount of ammonia sank to one-quarter in erysipelas, variola, typhus and typhoid fevers. It was in normal amount in cancer, heart diseases, and chronic alcoholism, and was increased ia *Proc. of Royal Soc. XX., p. 362. Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, INORGANIC. 87 diabetes and gout. It is said to almost wholly disappear from tlie urine shortly before death. In two hundred cases examined it was only twice wanting in the urine. Hilger found * a very considerable increase of ammonia after taking asparagus for a long time ; here it is evidently produced by the decomposition of the asparagin. Detection. To detect ammonium salts in acid urine, freshly- passed normal urine is precipitated with a mixture of acetate and subacetate of lead, filtered, and the filtrate, while cold, treated with milk of lime in a fiask. The flask is closed with a stopper on which a piece of moistened turmeric paper is fastened, when the brown color can be very quickly perceived. Now where does the ammonia, set free by milk of lime in the cold, come from ? Urea is not decomposed by milk of lime in the cold, and the coloring and extractive matters are removed by oxide of lead. As no substance is discovered in normal urine tohich is precipitated by the acetate and subacetate of lead, and is decomposed by milk of lime in the cold in a feio seconds with the development of ammonia, we must consider the presence of ammonium salts in nor- mal freshly -passed urine as established. For my quantitative estimations I used a method given by SchlossiDg, which depends on the fact that an aqueous solution containing free ammonia, when exposed to tha air at ordinary temperatures, allows its ammonia to evaporate in a relatively short time, when it is contained in as flat a vessel as possible in not too deep a layer. The ammonia which escapes is made to combine with a standard sulphuric-acid solution and is de- termined volumetrically. (See Part Second for description of the process.) After I had convinced myself of the usefulness and reliability of the method,t I commenced the determination of the amount of ammonia which is passed by a healthy man in twenty-four hours. My experiments showed that in twenty-four hours, on an average, 0-7243 gram of ammonia were secreted by a man frora twenty to thirty-six years of age, which corresponds to 2-2783 grams of chloride of ammonium. The amount varied in twenty-four experiments between 0-3125 and 1-2096 gram of * Erlanger Sitzungsbericlite, 1873. f Journ. f . pract. Cfiemie, Band 64, p. 177. Digitized by Microsoft® 88 ANALYSIS OF THE UBINE. ammonia, corresponding to 14272 and 3-8038 grams of chloride of ammonium. I started my experiments with two healthy men of twenty and thirty-six years respectively, and found that a somewhat greater amount of ammonia was passed in twenty- four hours by the latter on the average. The following sum- mary wUl serve to show the difference : Man of 30 years. Man of 36 years. Difference. NH3 NH4CI. NH3 NH4CI. NH3 NH.Cl. In twenty-four hours, 0-6137 1-9305 0-8351 2-6861 0-3314 0-7065 In 1,000 cc. of urine, 0-3939 1-2390 0-5245 1-6560 0-1306 04170 Chloride of ammonium, taken into the economy, passes out in part unchanged by the urine. § 20. Silicic Aero. Silicic acid occurs only in very small amount in the urine. To obtain it the following method is adopted : An amount of urine, not too small, is evaporated in a platinum or silver evapo- rating dish and ignited. The ash obtained is mixed with an ex- cess of a mixture of chemically pure carbonate of sodium and potassium, and fused for a time in a platinum crucible. The mass is dissolved in water, rendered acid with hydrochloric acid, and evaporated to dryness in a platinum dish on the water bath. The dry residue is extracted with hydrochloric acid and water, and pure silicic acid remains behind. The silicic acid thus obtained is white, pulverulent, without taste or odor, and grits between the teeth. It is soluble neither in water nor in acids, but boiled with a solution of carbonate of sodium it is taken up entirely without leaving any residue. (Tests of purity.) § 21. NiTBATES AND NiTBITES. According to the investigations of Schonbein, every normal urine contains small amounts of nitrates, which without doubt come from the food taken, since all spring and river water, as well as many vegetables, cabbage, spinach, salad, etc., contain small amounts of nitrates. The nitrates are gradually reduced to nitrites by the urinary fermentation which soon takes place Digitized by Microsoft® NORMAL CONSTITUENTS OF URINE, INORGANIC. 89 on standing, and they appear to suffer a further decomposition in the later stages of fermentation. The following are to be mentioned as delicate reagents for nitrous acid : 1. A deep blue color is produced by the slightest amount of nitrites with a paste of starch and iodide of potassium feebly acidified with dilute sulphuric acid. 2. An acidulated solution of pyrogallic acid is colored deep blue by nitrites with the evolution of nitric oxide gas. If the test is performed in a flask, the nitric oxide gas on contact with the air becomes nitric peroxide, which turns a strip of paper moistened with starch and iodide of potassium paste, and hung in the flask, blue, and decolorizes indigo paper. As long as the urine is completely clear, it never shows the re- actions given for nitrous acid ; if, however, a cloudiness appears, due to commencing fermentation, the formation of nitrous acid immediately takes place, and the urine now shows an evident re- action with sulphuric acid and iodide of potassium, and starch paste. Also an indigo solution acidulated with hydrochloric acid and then completely decolorized by adding a few drops of potassic pentasulphide (Mehrfachschwefelkalium) is made blue again directly by such a urine. (Preparation of this reagent, see § 22, 2.) After long standing (eight to ten days) it shows these reactions in a greater degree, and finally gradually loses this power again wholly. If the urine is in that condition in which it blues the acidified iodide of potassium and starch paste most powerfully, it also gives the above-mentioned reac- tion with pyrogallic acid, etc. It is easy to determine that fresh urine contains nitrates, according to Schonbein, if it is treated with potassium hydrate, and evaporated. Sulphuric acid sets free from the residue fumes which deeply blue the iodide of potassium and starch paste, and bleach indigo paper. The sulphuric acid here in the presence of alkaline chlorides sets free from the nitrates chlorine and hyponitric acid, which give rise to the reactions cited, § 22. Hydeogen Peeoxide. This curious body was also first detected in the urine by Schonbein. The following reactions serve for its recognition : 1. Hydrogen peroxide bleaches a dilute tincture of indigo Digitized by Microsoft® 90 ANALYSIS OF TEE URINE. only very slowly, but if only a few drops of a dilute solution of ferrous sulphate are added, the mixture becomes completely freed from its color in a short time. 2. If water is colored blue with tincture of indigo, so as to be non-transparent, treated with a little hydrochloric acid and then a few drops of a solution of potassic pentasulphide (Mehr- fachschwefelkalium) added with stirring, the mixture becomes completely free from its blue color. If in the preparation of this reagent no more sulphuret of potassium was added than was just enough to decolorize the indigo tincture, the colorless and clear filtrate will be distinctly and immediately blued by water, which contains only traces of hydrogen peroxide, when a few drops of a dilute solution of ferrous sulphate are added to the mixture. By an excess of hydrogen peroxide, however, the blue color is made to disappear again. (Reaction 1.) 3. Hydrogen peroxide in the presence of ferrous sulphate immediately blues iodide of potassium and starch paste. This extraordinarily delicate reaction cannot be used, however, in urine, since every urine is able to form compounds with con- siderable quantities of free iodine, and consequently the blue coin cannot occur. Detection in Urine. To about 200 cc. of freshly passed urine a solution of indigo is added, drop by drop, until the mixture shows a distinct green color, it is then divided into two equal parts. If fifteen or twenty drops of a dilute solution of ferrous sulphate are added to one half, the' color will soon appear to be of a lighter green or brownish yellow, a change of color which evidently comes from a partial or total destruction of the indigo tincture, while, on the contrary, the half free from iron con- tinues to show its original green color. If, further, eight or ten drops of indigo tincture decolorized exactly by sulphuretted hydrogen (reagent 2) are allowed to drop into thirty or forty cc. of fresh urine, the mixture will not become colored blue at first, but only after adding a few drops of solution of ferrous sulphate. Sulphurous acid, which quickly reduces hydrogen peroxide, added to the urine in correspondingly small amount, hinders both reactions. Digitized by Microsoft® ABNOBMAL CONSTITUENTS OF UBINE. 91 III. ABNORMAL CONSTITUENTS OF URINE. § 23. Albumen. {Serum Albumen.) Scherer. Mulder. ' Carbon 54-883 63-5 Hydrogen 7-036 7-0 Formula unknown. ^itrogen 15-675 15-5 Oxygen \ 33 -q Sulphur V 32-365 1-6 _ Phosphorus j 0-4 99-958 100-0 A. Presence. It is well known that albumen is the most im- portant substance which the animal body requires for its preser- vation; it furnishes the material for its nourishment, as well as for the renewal of wornout organs. Its diffusion, therefore, in the whole body is large ; it forms the chief constituent of the blood, the lymph, the chyle, all the serous fluids, and the liquids of the cellular tissue. In the normal condition, albu- men does not occur in the urine, but it occurs so frequently under pathological conditions, that it is necessary to test for it in every specimen whose composition we wish to ascertain. It occurs most frequently in all affections of the kidneys which are embraced under the name of Bright's disease. W. Leube* found albumen in the sweat at different times. Waldenstrom t repeatedly observed urine containing albumen, both after the external and internal use of carbolic acid. B. Preparation of Pure Albumen. Blood serum is treated with very dilute acetic acid, drop by drop, till a flocculent pre- cipitate just forms, it is filtered, the filtrate evaporated in a vacuum, or on a water bath, at 40° C, to a small volume, nearly saturated with carbonate of sodium, and the residue subjected to dialysis. If, after frequent renewal of the external water, no more salts pass through the dialyser, the contents of the cell is evaporated in a vacuum again, or on a water bath at 40°, to dry- * Vircliow's Archiv, Band 48, p. 181. f Neues Jahrbucli d. Pharm., Baud 34, p. 111. Digitized by Microsoft® 92 ANALT8IS OF THE URINE. ness. Albumen, tlius prepared, is not yet wholly free from salts. (Hoppe-Seyler.) 0. Chemical Properties. Purified serum albumen is, in the dry state, a yellow, Titreous, translucent mass, which dissolves in water to form a viscid fluid. 1. A solution of serum albumen, with which the albumen oc- curring in urine is identical, has, in neutral aqueous solu- tion, a specific rotation of the plane of polarization of —56° for the line D of the solar spectrum. 2. Alcohol causes a precipitate in solutions of albumen, which, partly at least, dissolves in water again, if the alcohol is re- moved immediately. By the prolonged action of alcohol all of the serum albumen appears to be coagulated. 3. If a solution of albumen is treated with acetic acid until it has a strong acid reaction, and then a few drops of ferro- cyanide of potassium solution are added, a white, flocculent precipitate is produced. (Quantitative volumetric estimation by the method of Bodeker.) 4. If albumen is heated with concentrated hydrochloric acid, or better, after the addition of a little sulphuric acid, a violet fluid results. 5. Concentrated nitric acid colors a fluid containing albumen yellow, after the application of heat (xanthoproteic acid). After the addition of sodic hydrate, the yellow color of the solution becomes orange red. 6. If a solution of albumen is warmed in a test tube over a spirit lamp, it commences to become turbid soon after the tem- perature has reached 60° or 65° ; it is observed that the cloudi- ness commences to be visible first at the surface of the fluid, and gradually spreads through the whole. Soon a flocculent, white, or, under certain circumstances, more or less colored coagulum occurs, since albumen at 72° or 73° C changes to the insoluble form. There are, however, several things to be ob- served in this simple reaction : if the albumen is very dilute, the cloudiness often occurs only after boiling the fluid, from which, at times, distinct flakes separate, especially after pro- longed boiling or standing. If the reaction of the fluid is feebly acid, a complete coagulation results in most cases, if the acid is not in excess ; if the solution has a neutral or alka- line reaction, only a slight cloudiness follows on heating, even Digitized by Microsoft® ABNOBMAL CONSTITUENTS OF URINE. 93 when the amount of albumen is considerable ; it remains in solution combined with potassium. If, however, before heat- ing, as much acetic acid is added as is necessary to saturate the alkali, the separation takes place completely in the form of coarse flakes. An excess of acid, however, is to be carefully avoided, since otherwise the albumen remains more or less dis- solved by the acetic acid, even on boiling. Chloride of sodium and other neutral salts of the alkalies lower the temperature at which a solution of albumen coagu- lates, therefore this takes place in acid urine usually below 70° 0. 7. If a solution of albumen is treated with acetic acid until it has a strong acid reaction, and an equal volume of a saturated solution of sulphate of sodium is added to the fluid, and then heated to boiling, complete coagulation results. 8. A solution of mercury prepared by dissolving the metal, first in the cold and then with moderate heat, in its own weight of strong nitric acid, of specific gravity 1"41 (boiling point 115° to 120° C), diluting with two volumes of water, and after stand- ing a while decanting from the crystalline precipitate, forms the most delicate reagent for albumen, as well as for all protein bodies, whether dissolved or undissolved. If we heat a fluid containing albumen with this mercury solution to from 60° to 100° C, an intense red color is obtained, which disappears neither in the air nor on prolonged boiling. Millon's reagent can, according to Vintschgau and Gintl,* be prepared as follows : a little nitrite of potassium is added to a solution of mercuric nitrate and the necessary amount of nitric acid added only when the reaction is performed. 9. Dilute nitric acid added in not too small amount gives in solutions of albumen a white precipitate of nitrate of albumen which is soluble in an excess of nitric acid and an excess of water. (Important reaction.) Other mineral acids behave in the same manner. 10. Most metallic salts, as alum, cause precipitates of varying composition. The precipitate produced by mercuric chloride (corrosive sublimate) is especially important. *Chem. Centralbl,, 1869, p. 860. Digitized by Microsoft® 94 ANALYSIS OF THE UBINE. 11. Sugar and concentrated sulphuric acid produce a beauti- ful red color with all protein bodies, just as with the biliary acids. (See Biliary Acids.) (Schultze.) 12. Albuminoid bodies treated with a solution of sulphate of copper and then warmed after the addition of hydrate of potas- sium or sodium, gire the solution a beautiful violet color. This reaction does not appear or only incompletely when the alkali is added before the copper salt. 13. Solid albumen on being treated with sulphuric acid con- taining molybdic acid becomes colored a beautiful dark blue. (Fr5hde.)* Albumen reacts to most of the above tests in common with the other protein substances. 14 All albuminates, the peptones and unformed ferments not excepted, when dissolved in excess of glacial acetic acid, give after the addition of concentrated sulphuric acid beautiful violet - colored solutions, which have a feeble fluorescence. When properly concentrated these fluids produce in the spec- trum an absorption band which, like that of urobilin and chole- telin, lies between the lines b and F. (A. Adamkiewicz.) D. Preparation of Albumen Absolutely Free, from Salts by Biffur sion. B. Aronstein t obtained by the dialysis of an alkaline or neutral solution of albumen, by making use of the finest Eng- lish parchment paper, and continuing the process three or four days at a temperature of +10° to 12° C, during which the external water was changed two to three times, an albumen which on being ignited left no trace of ash behind. The chief properties of this pure preparation are as follows : 1. Albumen is a body completely soluble in water, and neither the soluble nor the insoluble salts in the animal fluids aid in retaining it in solution. 2. Pure albumen is coagulated neither by a boiling tempera- ture nor by alcohol ; the coagulation which is thus produced is caused only by the salts in its natural solutions. 3. There is no compound of albumen with the insoluble salts of the animal fluids, to which these salts owe their solubility in the latter ; they are kept in solution rather by means of an * Zeitschrift f. analyt. Chem., Band 7, p. 366. f Arcliiv fiir Pliysiologie, Band 8, p. 75. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. gg organic substance contained in blood serum, as well as in the albumen of eggs, and whicli does not belong to the class of albuminoid bodies. 4. Blood serum, like egg albumen, contains, besides the albu- men, another albuminoid body, paraglobulin, dissolved by the crystalloid constituents. E. Detection. The recognition of albumen in urine depends on very simple tests, which, carried out with care, allow of an accurate conclusion. In the first place the reaction of the clear or previously filtered urine is determined, a small test tube is then about half filled and heated over the spirit lamp. If the urine has an acid reaction and albumen is present, as soon as the temperature has reached 50^ or 60° C. a cloudiness will make its appearance at the surface of the fluid, which is soon fol- lowed by a coagulation of the albumen. If, however, the urine is neutral or alkaline, for the reason given above, the precipi- tation does not take place, but for the most part only a milky turbidity. But if in this ease the boiled urine is treated with nitric acid until it has a strong acid reaction, a permanent pre- cipitate takes place, when albumen is present. But it is to be remarked that the nitric acid must be added in considerable excess, since albuminoid bddies may remain in solution when too little is added. Nitric acid has many advantages here over acetic acid, which has been heretofore used for rendering urine acid, since, in the first place, the addition of acetic acid must be made with great care, for an excess completely stops the separation of albumen, and, in the second place, acetic acid, according to the investigations of Beissner, causes, in a urine which contains dis- solved mucus (mucin), a similar turbidity insoluble in an excess of acetic acid, which may readily be mistaken for a separation of albumen. For further confirmation of the presence of albumen the re- actions 3 and 7 are of especial service. Cases may occur, however, where a precipitate forms on boil- ing the urine, especially when it is only feebly acid or neutral, even when no trace of albumen is present. This precipitate consists of the earthy phosphates which are held in solution in feebly acid urines mostly only by free carbonic acid, after the •expulsion of which by heat they are precipitated in flocculi, and Digitized by Microsoft® gg ANALYSIS OF TEE URINE. in this form can scarcely Ise distingmshed from coagulated albu- men by tbe naked eye. Tbe doubt is readily removed if, after cooling, nitric acid is added to tlie fluid in whicb the precipitate is suspended, and tbe mixture shaken ; if the precipitate con- sists of phosphates they will dissolve and the fluid become clear; if, however, it is albumen, it will not disappear. This frequently happens, so that the subsequent test with nitric acid, especially when the cloudiness which occurred on heating was but small, must never be omitted. If, moreover, the urine contains resinous matters, as, accord- ing to Maly's investigations, may be the case after the internal use of turpentine, balsam copaiba, etc., a whitish-yellow cloudi- ness, not unlike precipitated albumen, occurs after the addi- tion of hydrochloric or nitric acid, which immediately disap- pears, however, after the addition of alcohol, and thus may be easily distinguished from albumen. The test with nitric acid can also be performed in the follow- ing very neat manner, according to Heller. A test tube is filled about half an inch high with pure concentrated nitric acid, and a layer of the clear urine to be tested is poured carefully down the side of the tube by means of a pipette, so as to cover the acid. If the manipulation is well performed the urine floats on the nitric acid, and the mixture of the two takes place gradu- ally. At the point of contact there is formed almost always an intense red, violet or blue ring, the indican reaction. Care must be taken not to confound this play of colors with the re- action of the biliary coloring matters, unless a green color can be distinctly recognized under the blue. If the urine contains albumen, a cloudy zone, sharply bordered above and below, forms on applying this test at the point of contact of the two fluids, which zone can be recognized with great distinctness even when only traces of albumen are present. The reaction lasts quite a while, but after a long time the coagulated albumen gradually sinks to the bottom. A turbidity, similar at first sight, may also occur when the urine contains an abundance of urates ; a cloudy zone also forms in this case, but it stands at a higher level than the albumen zone. The lower edge, also sharply defined, stands above the point of contact of the two fluids, usually higher even than the upper border of the albumen zone ; it is, moreover, not sharply bordered above, but diffused and Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 97 rising toward the surface of the urine. If the urine contains albumen, and at the same time a large amount of urates, two zones may form, a lower one of albumen, which is separated from the upper one of urates by a clear layer. It is better, however, in such a case to dilute the urine with two or three parts of water before testing it, in order to prevent the urate reaction, or at least to reduce it to a minimum. Turbidity from urates, moreover, disappears on the application of gentle heat, and all doubt can thus be removed readily. A precipitate of nitrate of urea may also take place in very concentrated urines, but this is crystalline and disappears immediately on the addi- tion of water. Mehu * uses for testing for albumen, qualitatively, a mixture of equal parts of crystallized carbolic acid and commercial acetic acid, with two parts of 90 per cent, alcohol. Two or three per cent, of nitric acid and about ten per cent, of this carbolic acid solution are added to the urine, the mixture is shaken, and al- lowed to settle. The deposit takes place more quickly if, instead of nitric acid, one-half of its volume of a saturated solution of sulphate of sodium is used. This is a delicate reaction and very minute traces of albumen may be detected with certainty. SUPPLEMENT. § 24. FiBEiNE, Casein, Aibtotinosb, Paealbumen, Pabaglobulin', Peptone, Nephkozymose. 1. Fibrine. Of the above protein substances, fibrine sometimes occurs in the urine. It separates in somewhat large masses, especially in cases of severe inflammation of the kidneys and urinary passages. Such a urine always contains blood also, and, as a result of this, albumen. Ackermann found fibrine in the urine in galacturia. I shall speak under the head of sedi- ments of the peculiar tube-like urinary casts, which Ererichs regards as flattened coagula of fibrine. Isolated cases have been observed, also, in which fibrine separated from the urine partly as a gelatinous mass, and partly as granular or fibrillated clumps. * Zeitschrift f. analyt. Chem., Band 8, p. 522. Digitized by Microsoft® 98 ANALYSIS OF TEE URINE. 2. Casein. Casein lias not yet been detected with certainty in the urine. There are, moreover, at times protein substances, which ap- pear in urine, which do not correspond in their characteristics to the ordinary ones. Thus Bence Jones describes a case * in which he found in the urine of a man suffering from "softening of the bones," together with casts a peculiar albuminous sub- stance which was characterized by being soluble in boiling water, precipitated by nitric acid, and dissolved on heating, but again separated on cooling. By its behavior with the reagents spoken of above under albumen, as acetic acid, ferrocyanide of potas- sium, etc., it was proved to be, without doubt, a protein sub- stance ; but we cannot regard it as albumen or casein on account of its anomalous behavior with water and nitric acid, at least not until we have succeeded in converting albumen or casein artificially into these peculiar modifications. 3. Albuminose. Baylon describes an albuminoid substance un- der the name of albuminose, which is said to occur also in nor- mal urine. According to Mialhe this substance has the same relation to albumen that glucose has to starch (?). Albuminose is not precipited by heat, acids, or alkalies, it is precipitated by tannin and many metallic salts. It is said, as already remarked, to occur in every normal urine as well as in pathological cases. In a urine of Bright's disease, however, where there was much albumen, no albuminose could be found. Baylon designated cupric tartrate as a very delicate reagent for albuminose. After the addition of a few drops of potassie hydrate the urine is boiled, filtered, and then a solution of cupric tartrate added, until the mixture has a faint blue color. After one or two hours tartrate of albuminose (?) precipitates, which dissolves on heating, but separates again on cooling.f C. Gerhardt X states that different varieties of albumen occur in the urine of patients suffering from kidney disease. In sev- eral cases the urine was precipitated neither by boiling nor by the addition of nitric acid, but alcohol separated substances which gave decided reactions for albumen. * Annal. d. Chem. u. Pharm., Band 67, p. 97 to 105. f Canstatt's Jahresbericht, 1860, p. 270. t Oentralblatt f. d, med. Wissenacliaft.,1869, p. 174. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 99 4. ParaJhumen and ParaghbuUn. E. Masing * also describes a case of Bright's disease in wliicli the urine, together with serum albumen, contained much paralbum'en. This urine gave im- mediately, after the addition of water, a milky cloudiness, which disappeared on being treated with acids, alkalies, and also with a solution of common salt. Edelfsent made the same observation in thirty-one cases of albuminuria. The cloudiness of the urine, on dilution with water, first occurred after a few minutes, and was for the most part increased by the introduction of carbonic acid. Edelfsen considers this albuminoid body, as well as the paralbumen found by Masing, to be paraglobulin, although he did not suc- ceed in causing the coagulation of fluid containing fibrinoge- nous substance by means of it when precipitated. Detection of Paraglobulin in Albuminous Uritie. The urine, after filtration, is diluted with water till its specific gravity sinks to 1,003 or 1,002, so that its amount of solid constituents is excessiveily small. Under certain circumstances, the dilution alone may give rise to the separation of paraglobulin, at least Edelfsen observed:]: a cloudiness frequently as soon as he had diluted the albuminous urine with water, in the proportion of 1 : 20. If now carbonic acid is conducted through the dilute fluid, for from two to four hours, almost all albuminous urines give turbidities of paraglobulin, which often, after from twenty- four to forty-eight hours, settle as distinct precipitates. (H. Senator.) § The precipitate thus obtained is milk white, of a fine, floccu- lent character, and dissolves completely on the addition of a one per cent, hydrochloric acid solution, also of a few drops of a solution of common salt, and likewise in concentrated acetic acid. It separates so completely from the solution of salt, on heating, that no trace of an albuminous body is any longer de- monstrable in the filtrate. The flakes separated on heating do not dissolve again in acetic acid, at least if added in mode- rate amount. If the precipitate is dissolved- in a trace of sodic hydrate, filtered, and treated with clear pericardial or perito- * Beitrage zu Albuminometrie, Dorpat, 1867, bei H. Laakmann, f Centralblatt f. h. med. Wissenschaft, 1870, p. 367. X Deutscli. ArcMv. f. klin. Med., Band 7, p. 69. § Virchow's Arohiv, Band 60, p. 476. Digitized by Microsoft® 100 ANALYSIS OF THE URINE. neal fluid, a turbidity occurs on shaking, which, after prolonged standing, is followed by a copious flocculent precipitate. According to Senator, paraglobulin can be detected in every urine which contains coagulable albumen. Of the chronic kid- ney diseases, amyloid degeneration appears to yield the urine which is relatively richest in paraglobulin. Alkali albumi- nate, or a body which is obtained from the blood serum after precipitation of the paraglobulin by acetic acid, does not ap- pear to occur in the urine at all, or only in slight traces. 5. Peptone. Peptone-like bodies were found by O. Schultzen and L. Eiess * in the urine, after phosphorus poisoning. These, by precipitating from the strongly concentrated urine by alco- hol, redissolving in water, and reprecipitating with alcohol, were obtained free from all coloring matters. The identity of this peptone-like substance with the true albumen peptones is still doubtful. Detection of Peptone in Albuminoiis Urines. The albumen is removed from albuminous urines by heat, with or without the addition of acetic acid, by the familiar method, and the fil- trate mixed with three times its volume of alcohol by shaking. The precipitate which takes place, dissolved in water after , washing with alcohol, is colored yellow on heating with nitric acid, and, in short, shows all the reactions of an albuminous body. Gerhardt t observed peptone frequently in urine which was free from albumen ; he found it sometimes as a forerunner, and sometimes as a follower of ordinary albuminuria. Senator X was able to detect peptone in every albuminous urine in small amount. 6. Nephrozymose. Finally, according to Bechamp, a pro- tein substance can be precipitated from every normal urine by three times its amount of 88 to 90 per cent, alcohol, which, after washing, is soluble in water; it is capable of changing starch into sugar at 60° to 70° C, and Bechamp has given it the name of nephrozymose. * Annalen des Charite Krankenhauses zu Berlin, Band 15, p. 9, etc. f Wiener med. Presse, 1871, p. 1. fLoc. cit., p. 488. Digitized by Microsoft® abnormal constituents of urine. 101 § 25. Ubinabt Sugab. Gbape Sugae. Anhydrous : Carbon 40-00 Crystallized : 36-36 Hydrogen 6-66 7-07 Oxygen 53-34 56-57 100-00 100-00 Formula: GeH.A [C,,H,,0,J OeH^O.+H^a [C,sH,,0,,+2aq.J. A. Presence. Grape sugar, whicli is perfectly identical with urinary sugar, is found, as is well known, Tery wide-spread in the vegetable kingdom. But it also occurs in the animal king- dom, partly normally, partly in disease in various fluids. Grape sugar always exists in the contents of the small intes- tine, and in the chyle, after taking food containing sugar or starch ; it is found in the hen's egg — both in those in the pro- cess of hatching and in those not being hatched, in the yolk as well as in the white — in the amniotic and allantois fluids of cows, sheep, and swine, and in the liver. Bernard also flnds it constantly in the blood, especially in the hepatic vein; the blood of the portal vein, on the contrary, contains no sugar, so that its formation must occur in the parenchyma of the liver. According to the most recent and comprehensive investiga- tions of Seegen,* there appears to be no doubt whatever that the excretion of sugar by the urine is not a physiological func- tion, and that normal urine, contrary to the assertions of Briicke and Bence Jones, contains no sugar. Sugar occurs in large amount only in diabetes mellitus, but it is then increased in the blood, the vomitus, the saliva, the sweat, etc. Sugar has also been found in the urine, at times, in other diseases ; it appears to occur especially in disturbances of the abdominal circulation. By wounding certain points of the medulla oblongata in ani- mals sugar may be made to appear temporarily in the urine. According to Lehmann sugar appears in the urine of women from twenty-four to forty-eight hours after weaning an infant. These observations of Lehmann correspond to the assertions of De Sinety,t according to whom, whenever there is an obstruc- * Seegen, Der Diabetes Mellitus, 2 Aufl., p. 196. f Gazette med. de Paris, 1873, p. 573. Digitized by Microsoft® 102 ANALYSIS OF THE URINE. tion to the flow from the lacteal gland, sugar appears in the urine. If, on the contrary, the production and discharge of milk retains its equilibrium, sugar disappears from the urine, and the latter becomes normal. WoUert and Almen * observed the occurrence of sugar in the urine after the internal use of oil of turpentine. According to the investigations of A. Ewald,t subcutaneous injections of nitrobenzol and nitrotuluol give rise to saccharine urine in rabbits. In dogs, however, it was seen only when nitrobenzol was given in large doses internally (0'8 to 3 grams). F. A. Hoffmann % also observed a large amount of sugar in the urine in rabbits after the injection of 0'2 to 0*6 gram of nitrite of amyl. B. Microscopic Properties. Diabetic sugar crystallizes in irregular masses, which appear as warty conglomerations, and consist of cauliflower-like groups of laminae. These laminae have a rhombic shape. If the crystallization takes place rapidly it does not appear in laminae even when seen under the micro- scope, but in irregular, striated roundish masses. C. Preparation of Chemically Pure Grape Sugar. — 1. If pure cane sugar is dissolved in 80 per cent, alcohol, to which a little hydrochloric acid has been added, with frequent shaking until it is saturated, after long standing chemically pure grape sugar separates in white crystalline crusts. (H. Schwarz.) After a long time, when no further separation follows, the crystals are collected, thoroughly washed with alcohol, dried in a dessicator, and finally recrystallized from boiling absolute alcohol. 2. The best starch sugar is dissolved on the water bath in about half its weight of water, and then filtered into a glass fun- nel whose orifice is closed with a stopper. When the funnel is nearly filled it is covered with a glass plate and put on a stand in a cool place for several months, when the grape sugar crys- tallizes out as hydrate. The mother liquor is allowed to flow away, the sugar is covered with a layer of 80 per cent, alcohol, and treated with it until the sugar is dazzlingly white. Then it is dried, first in the open air, and finally in a dessicator over chloride of calcium. * Neues Jahrb. d. Pharm,, Band 34, p. 163. f Centralblatt f. d. med. WisseDschaft.,1873, No. 53. i ArcMv fur Anatom. u. Physiologie. 1873, p. 746. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 103 Heat is to be applied only when most of the moisture is re- moved, because otherwise the sugar is softened by the moisture and cakes together. (Mohr.) D. Chemical Properties. Pure grape sugar is white, odorless, by no means as sweet as cane sugar, and is also less soluble in water. Its solution has no reaction on vegetable colors, and turns polarized light to the right. It is quite soluble in alcohol, not at all so in ether. If crystallized grape sugar is exposed for a long time to a temperature of 100° C, it loses its water of crystallization. 2. The specific rotation of an aqueous solution of grape sugar, if the solution has been heated or has stood a long time, is + 56"4 for yellow light. A freshly prepared cold solution causes a greater rotation to the right of the plane of polarization when tested immediately after dissolving it, but on long standing, and more quickly if heated, it sinks to + 56'4* 3. In contact with bodies containing nitrogen, especially casein, it undergoes lactic acid and, later, butyric acid fermen- tation. In diabetic urine it changes into an acid even at medium temperatures, more quickly at a temperature of from 25° to 40° C, which, according to circumstances, may be acetic, butyric, or even lactic acid. 4 Grape sugar forms with several bases peculiar compounds called saccharates. a. Saccharate of Potassium, KoO + OgHisOg [3KO + C,sH,20,sJ, is readily obtained if an alcoholic solution of sugar is mixed with a solution of caustic potash in alcohol. The compound precipi- tates immediately in white flakes, which stick toigether when exposed to the air, deliquesce, and attract carbonic acid. b. Saccharate of Calcium.. If a solution of sugar is treated with an excess of quicklime, the solution filtered and the filtrate treated with alcohol, this compound separates as a white mass. c. Compound of Grape Sugar tvith Chloride of Sodium, NaCl, 2(e,H,,,a,) + H,a []SraCl,2C,,ri„0,, + 3H0]. if a solution of grape sugar is mixed with a solution of chloride of sodium, and the mixture left to spontaneous evaporation in the air, the com- pound crystallizes in large, colorless, six-sided double pyramids or rhombohedra. The crystals are hard, readily pulverizable, * Zeitschrift f. analyt. Cheni., Band 14, Heft 3 u. 4. Digitized by Microsoft® 104 ANALYSIS OF THE URINE. easily soluble in water, and difficultly so in alcohol. They con- tain 13 "52 per cent, of chloride of sodium. 5. If a solution of grape sugar is warmed with potassic or sodic hydrate, it becomes a beautiful brown-red color ; if nitric acid is then added, a piercing, sweetish odor is evolved, which reminds one partly of caramel and partly of formic acid. 6. If a solution of indigo carmine, made alkaline with carbo- nate of sodium, is heated with a little grape sugar to boiling, it becomes colored, if only a small amount of sugar is added, first green then purple, and, with more sugar, red, and finally yel- low. If the hot yellow solution is shaken, so that the oxygen of the air can act upon it, the play of colors is reversed., The mixture becomes colored purple red, then green, and finally blue again ; yet on standing quietly the yellow color soon reap- pears. (Mulder.) This reaction is very brilliant, and allows very small amounts of sugar to be detected. With mere traces of sugar only a very weak blue indigo solution should be used. 7. If a solution of sugar is treated with a little caustic potash and a few drops of a solution of sulphate of copper, either no precipitate occurs, or that which takes place dissolves again to a beautiful blue fluid. If this mixture is heated, the fluid is first colored orange yellow, soon becomes cloudy, and finally a beautiful red precipitate of cupreous oxide separates. This reduction takes place after long standing in the cold without the application of heat. According to the investigations of Salkowski this reaction has two phases. First a bluish-green precipitate occurs, a compound of hydrated cupric oxide with sugar, which dissolves in an excess of sodic hydrate which soon decomposes it. An excess of sodic hydrate is absolutely neces- sary in the employment of the reaction. Uric acid, hypoxan- thin, mucus, etc., likewise cause a reduction of cupric oxide when heated, while red cupreous oxide is separated. It is well, moreover, to bear in mind that many substances by their presence may hinder the separation of cupreous oxide, as, for example, albuminous matters, especially peptone, kreatin, kreatinin, pepsin, urinary coloring matter, etc. 8. If a solution of sugar is placed in a small flask with a little yeast, fermentation will soon occur, especially at a tem- perature of 15° to 20° 0. Its progress can be very well ob- served in the following apparatus, fig. 2. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 105 A is a small glass flask, in wliicli tlie solution of sugar is brought in contact witli the yeast ; p^^ 3 this flask is connected with a small flask, B, which is half filled with lime or baryta water by means of the glass tube, c. The tube, a, is closed at the top by a piece of wax, h. If the mixture. A, is heated to the above temperature, the solution of sugar will become cloudy after a short time ; it commences to foam consid- erably, and bubbles of gas develop very regularly. This gas consists of carbonic anhydride, and, on going through the baryta or lime water, will render it cloudy by the separation of carbonate of barium or calcium, which will be precipitated. When the evolution of gas finally ceases, the fluid in A becomes clear, has lost its sweet taste, and instead has assumed a vinous one. The sugar is decomposed into alcohol and carbonic anhydride, during which decomposition, however, a few alcohols homologous to ethylalcohol are always formed in small amount, as well as traces of glycerine and succinic acid. If the amount of sugar is small, a test tube is filled with mercury and inverted in a small mercury bath. By means of a pipette with a curved point, a little neutral or faintly acid solu- tion of sugar treated with active well-washed yeast is allowed to rise in the tube, and is left at rest at a temperature best of 25° or 30° C. If, after one or two days, the development of gas is ended, a little concentrated potassic hydrate is allowed to rise up into the fluid by means of the pipette, and this wiU completely absorb the disengaged gas. 9. If a solution of grape sugar is treated with a weak ammo- niacal solution of nitrate of silver, and is heated to boiling and kept for a time at this temperature, it deposits metallic silver in the form of a beautiful polished metallic mirror. This re- duction can be of service under certain circumstances, since it is not prevented by the presence of ammonia. It is not to be forgotten, however, that many other matters, as, for example, tartaric acid, etc., reduce nitrate of silver in a similar manner. Digitized by Microsoft® 206 ANALYSIS OF TEE UBINE. 10. If a solution of sugar is treated with' an equal volume of carbonate of sodium solution (three parts of water and one of crystallized salt), a little subnitrate of bismuth added, and boiled awhile, the oxide of bismuth is reduced with a black color. The slightest blackening, or a gray coloration of the snow-white bismuth salt, shows the presence of urinary sugar in the most decided manner, since, according to Bottger, no other constituent of urine has a reducing action on that salt of bismuth. The urine must, however, be absolutely free from albumen, since otherwise black sulphide of bismuth is readily formed, which may give rise to erroneous conclusions. The reaction is quite successful also with an alkaline solu- tion of bismuth oxide, which is obtained by precipitating a solution of bismuth with a large excess of sodic hydrate, and adding drop by drop, with gentle heat, a solution of tartaric acid, until the precipitate which takes place is just dissolved again. According to Almtn, four grams of Eochelle salt are dis- solved in one hundred of potassic hydrate of specific gravity 1"33, gently warmed, and subnitrate of bismuth added as long as it dissolves ; about two grams will be necessary. 11. If a solution of sugar containing hydrate of potassium is treated with a few drops of molybdate or tungstate of am- monium, heated to boiling, and then acidulated carefully with hydrochloric acid, there results a blue color of molybdate of molybdenum, or tungstate of tungsten. In hydrochloric acid solutions sugar reduces at the boiling temperature only the molybdic acid, with the formation of a blue color; yet this reaction is not nearly as delicate as in an alkaline solution. (Huizinga.)* E. Detection. The methods of detecting sugar in the urine are different, according to the amount supposed to be present. If the twenty-four hours' amount of urine is large (four to six liters), if the color is greenish yellow, and, at the same time, the specific gravity is high, at least above 1*020, it is probable that the urine to be tested is diabetic. In this case the detec- tion of the sugar is simple, since diabetic urine, decolorized by animal charcoal, behaves very nearly like a pure solution of sugar with almost all reagents. If the urine in question is also *Archiv d. Physiologie, Band 3, p. 496. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 107 free from albumen, which mast be ascertained according to § 23, the different tests for grape sugar can be directly em- ployed; in other cases, however, it must be first freed from albumen, observing the precautions given in § 23. To prove the presence of sugar, we proceed as follows : 1. Fifteen or twenty drops of the urine to be tested, decol- orized with animal charcoal, and diluted with 4 or 5 cc. of water, are treated with half a cc. of sodic or potassic hydrate, and then a very dilute solution of sulphate of copper is added drop by drop. If sugar is present, the precipitate first formed after shaking dissolves to a clear blue fiuid. Too large an amount of the copper solution is to be avoided, especially if only small amounts of sugar are supposed to be present, since otherwise a . black oxide of copper also separates on boiling, which conceals the red cupreous oxide which is formed at the same time. The clear blue solution is then heated nearly to boiling, without shaking, when a yellow cloud forms on the surface, and soon a precipitate of yellow or red cupreous oxide will follow without being heated further. The mixture of urine and potassic hy- drate must not be heated before the addition of the solution of copper, since the sugar, especially if only a small amount is present, may be so changed that it no longer has a reducing action on the cupric oxide. A second mixture, prepared in the same way, is allowed to stand quietly, without previous heating, from six to twenty-four hours. If sugar is present, there will be a precipitate of cu- preous oxide in this case also. This control experiment is of great importance, and ought never to be omitted, since most of the substances which reduce the copper solution, like sugar, do so only when heated, or after prolonged boiling, and not like diabetic sugar in the cold. If the amount of sugar is small, it is advisable to filter the urine beforehand through animal charcoal (four or five times) to completely decolorize it. The filtrate, which is clear as water, gives much better reactions than the original urine. (Maly, Seegen.) Seegen * has found, further, that pure animal charcoal retains considerable amounts of sugar. If, therefore, after complete * Archiv d. Physiologie, Band 5, p. 375. Digitized by Microsoft® 108 ANALYSIS OF THE UBINE. decolorization, the charcoal on the filter is washed with a little distilled water, it gives a very pure reaction. If the urine has a high specific gravity and a deep color, the reaction of the first washing from the charcoal is usually not so sensitive ; but Seegen found that, in these cases, the second and third wash- ings gave a much more characteristic reaction. 2. A second specimen of urine filtered, decolorized, and freed from albumen, is diluted with an equal volume of a solution of carbonate of sodium, a small amount of subnitrate of bismuth is added, and the mixture is heated to boiling for a long time. According to the amount of sugar present, a partial or com- plete reduction of the oxide of bismuth will follow, and, there- fore, a gray or black color will occur. With small amounts of sugar, as little of the salt of bismuth as possible is to be taken, , in order that a slight reduction shall not be concealed by a considerable excess of the white salt. If the specimen is then allowed to stand quietly, the undecomposed oxide of bismuth first settles, and then the reduced bismuth follows beautifully and distinctly in the form of a velvet-black ring. The reaction also succeeds very well with the alkaline solution of bismuth. (See Eeaction 10.) 3. Another portion of the decolorized urine is placed in a tolerably long but narrow test tube, a little potassic hydrate is added, and the upper part of the column of fiuid is heated to boiling. If sugar is present, this part will be colored yellow or brownish red, while the lower part retains its original color. In this manner the slightest changes of color may be distinctly perceived. This reaction is to be highly recommended as a confirmatory test. The Reactions Nos. 6 and 9 give further confirmation, but especially the fermentation test, which may be undertaken in diabetic urine with the apparatus pictured in fig. 2. Sugar may readily be obtained from diabetic urine, pure and in crystalline form. The following methods serve for this purpose : I. A portion of urine is evaporated on the water bath to a syrupy consistence ; the residue is allowed to stand, and, after a long time, the sugar will crystallize out in yellow warty masses. It is freed from urea and extractive matters by treat- ing with absolute alcohol ; the sugar is then .extracted from the Digitized by Microsoft® ABNOBMAL OONBTITUENTS OF URINE. 109 residue by boiKng spirit, and the solution allowed to evapo- rate. The sugar will remain behind tolerably pure, and can be readily freed from the alcohol which adheres to it by repeated recrystallization from water. II. Lehmann's Method. An alcoholic solution is first prepared, by evaporating the urine and extracting with alcohol. This is evaporated to dryness, the residue dissolved in water, and the solution saturated with chloride of sodium. After evaporation, the chloride of sodium compound with sugar will crystallize, and may be obtained in pure crystals by repeated crystalliza- tion. They are dissolved in water, and precipitated carefully by sulphate of silver. The precipitate of chloride of silver is filtered off, and the filtrate evaporated to dryness; by extrac- tion with alcohol the sugar is obtained chemically pure. Without regard to the fact that these methods only succeed when the urine contains somewhat considerable quantities of sugar, yet cases occur in which the sugar is completely uncrys- tallizable, and differs from grape sugar by its power of turning polarized light to the left. In such cases, the residue of urine always remains syrupy and shows no trace of crystallization. HI. If the urine does not have the above characteristics, but still reduces the copper solution on being heated, without, how- ever, separating cupreous oxide, but at most producing a yel- low coloration of the mixture, it is necessary, in order to be able to prove the presence of sugar with certainty, to separate it in the purest possible form before the above reactions can be undertaken with a positive result. Eor example, a slight reduction of the copper solution can be caused by uric acid, etc., even when sugar is entirely absent. Even if a reduction should in fact be caused by sugar present, cupreous oxide may be held in solution by kreatinin, etc., wherefore this reaction loses all certainty. In this case there occurs at most a yellow coloration of the mixture without the characteristic precipita- tion of cupreous oxide. Such a solution on standing exposed to the air becomes colored blue again on the surface by oxida- tion. To avoid all of these uncertainties, any albumen present is first removed from a large amount of urine (500 to 800 cc.) according to § 23, the filtrate, or if no albumen is present, the original urine previously filtered, is evaporated on the water bath to a thick syrup, and allowed to stand in the cold from Digitized by Microsoft® 110 AN-ALYSIS OF THE UBINE. four to six hours. Then after the residue has been divided as much as possible with powdered pumice-stone, it is extracted with ninety per cent, alcohol, with which, in not tod small amount, the extract is allowed to remain in contact for at least some hours with frequent shaking. The clear filtered liquid is then treated with an alcoholic solution of pure potassic hy- drate, until precipitation ceases, without, however, making use of too great an excess. If sugar is present, saccharate of po- tassium precipitates as a pitchy, sticky mass, always together with other compounds of potassium in a crystalline or floccu- lent form. When the potassium saccharate has settled, the spirit is quickly poured off from the precipitate, the latter is washed repeatedly with absolute alcohol, whether it is flocculent, crys- talline, or pitchy, it is then dissolved in water, and the potassi- um quickly saturated with carbonic acid, in order to prevent a decomposition of the sugar. In most cases this solution gives the reactions already given, but since, under certain circum- stances, substances are precipitated with the potassium com- pound which have a reducing action on cupric oxide, the presence of sugar is not yet placed beyond all doubt. Accord- ing to Lehmann, therefore, the aqueous solution of the potas- sium precipitate, accurately neutralized with acetic acid, is pre- cipitated with acetate of lead solution in moderate excess, filtered, the excess of oxide of lead removed by sulphuretted hydrogen, again filtered, and the fluid, usually clear as water, is evaporated on the water bath almost to dryness, so that at all events all of the sulphuretted hydrogen is removed. The residue is dissolved in water, and the tests given in I. are per- formed. If they are successful, the presence of sugar may be considered as proved, since it is difficult for any other sub- stance to be contained in this fluid last obtained, which, like sugar, gives the reactions mentioned. In the copper test, if the mixture is allowed to stand in the cold, cupreous oxide will separate if sugar is present without the application of heat ; moreover, only small amounts of the cupric oxide solution are to be taken, so that the mixture shows only a slight blue color. Finally the fermentation test yields the final decisive proof ; this test can be carried out with great accuracy, even with very small amounts of sugar, in the apparatus described under Chemical Properties, No. 8. Fermentation occurs quickly in Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. m the presence of sugar, and to prove that the gas is not de- rived from the decomposition of the yeast, it is expedient to perform a control experiment with yeast and pure water. The alcohol formed by the fermentation can also be readily detected. For this purpose a few cc. of the fermented fluid are distilled, the distillate is treated with a few drops of a solu- tion of iodine in iodide of potassium, potassic hydrate is added, drop by drop, until it is just decolorized, and the mixture is allowed to stand for a time. If alcohol is present, there soon, or after standing awhile, occurs a yellowish cloudiness of iodo- form, which after complete settling is subjected to microscopic examination. Iodoform forms either regular six-sided tables very similar to cystin crystals or six-sided stars of great beauty. (Lieben.)* It must be remarked, however, that normal urine also, as Lieben has found, contains a volatile substance, which passes over on distillation and yields iodoform with iodine and hydrate of potassium. If we wish to subject the urine directly to fer- mentation with yeast, and to use the distillate for the iodo- form reaction, the urine must first be evaporated to one-half its volume before adding the yeast, so as to remove this volatile substance. In many cases where the original urine showed only very doubtful reactions for sugar, I have succeeded by this method in proving its presence with great distinctness by all of its re- actions. Leconte treated the potassium precipitate in the following manner : Tartaric acid in slight excess is added to its solution in as small an amount of water as possible, it is shaken, the tartrate of potassium is filtered off', and the cold filtrate treated with excess of carbonate of calcium till it has a perfectly neutral reaction. The filtrate is evaporated on the water bath, and the residue exhausted with absolute alcohol. This solution, after spontaneous evaporation, leaves behind, when sugar is present, a syrup, which after quite a long time, often only after months, deposits crystals which frequently fill the entire mass. If, however, one is content with the fermentation of the sugar instead of its extraction, according to Leconte the aqueous solu- * Annal. d. Chem. u. Pharm., Supplementbd. 7, p. 318. Digitized by Microsoft® 112 ANALYSIS OF TEE URINE. tion of the potassium precipitate is treated with dilute sul- phuric acid to saturation, the sulphate of potassium which separates after standing awhile is filtered off, a little water with yeast is added, and the mixture is put in the fermentation apparatus described. To find sugar in normal urine Briicke uses the following methods, which are best mentioned here : a. The urine (1,000 to 5,000 cc.) is first precipitated by a con- centrated solution of sugar of lead, filtered, the filtrate treated with subacetate of lead till precipitation ceases, again filtered, and finally precipitated with ammonia. The last precipitate is collected on a filter, washed with water, and finally allowed to dry between thick layers of blotting paper which are renewed from time to time. The crumbled cake is first rubbed rather coarsely in a mortar with distilled water, and then a concen- trated solution of oxalic acid is added with constant trituration, as long as a specimen filtered off continues to be rendered cloudy by further addition of oxalic acid. The filtrate is satu- rated with finely divided carbonate of calcium, again filtered, rendered feebly acid with acetic acid, evaporated to dryness, and the residue dissolved in a little water. Briicke performed the usual reactions with this solution as well as the fermenta- tion test. Bence Jones does not decompose the lead precipi- tate by oxalic acid, as Briicke does, but in a simple way, after it has been suspended in water, by means of sulphuretted hydrogen. Bence Jones found in several normal urines (1,000 to 5,000 cc.) by this method small amounts of sugar (2 to 3 grains in 1,000 cc. of urine). b. The urine is treated with strong alcohol till the mixture contains about four-fifths of absolute alcohol. It is well to take 200 cc. of urine, and mix it with 800 to 1,000 cc. of 94 per cent, alcohol. After it is mixed, a short time is allowed to elapse for the precipitate which has formed to settle, and then it is filtered into a beaker. An alcoholic solution of hydrate of potassium is then added, drop by drop, to the filtrate, with con- stant stirring, till a feeble though distinct alkaline reaction can be detected by litmus paper. The beaker is then allowed to stand twenty-four hours in a cool place, well covered up. The next day the fluid is carefully poured off, the beaker turned over on filter paper, so that the rest of the fluid may be ab- Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 113 sorbed, and then it is allowed to stand exposed to tlie air till the decided odor of alcohol can be no longer perceiyed. The bottom and, to a certain extent, the sides of the glass are coTered with a crystalline coating, which is to be dissolved in as little water as possible, and this solution employed for the reactions given. But since under certain circumstances uric acid may exist in this crystalline deposit, it is well in any case to acidify the concentrated aqueous solution with hydrochloric acid,, and leave it at rest for twenty-four hours, so that any uric acid present may separate. The neutral filtrate is then employed for the bismuth, copper, and potassium hydrate reactions, as well as for the fermentation test also when possible. The alcohol formed by fermentation is detected by the iodoform reaction, as given above, page 111, under III. Bodecker first precipitates the potassium with tartaric acid from the concentrated aqueous solution of the crystalline de- posit, removes the excess of the acid from the filtrate by car- bonate of calcium, with which he allows the fluid to be in contact for a time, filters from the excess of tartrate and car- bonate of calcium added, and uses the solution thus obtained for the copper, bismuth, and potassium hydrate reactions. But Seegen,* from his own investigations, considers that all the proofs of the occurrence of sugar in normal urine which Brucke and others advance are not sufficient, because the ap- pearances which they give as sugar reactions can be produced in the same intensity by other substances also, which are not excluded by the processes employed. The excretion of sugar by the urine is, according to Seegen, not a physiological function ; according to him, normal urine contains no sugar. The method recently given by Huizinga t for the detection of sugar in normal urine has not yielded me, on repeated trials, results which remove all doubt. * Seegen, Der Diabetes, 2 Aufl., p. 324. f Archiv d. Physiolog., Band 3, p. 496. Digitized by Microsoft® 114 ANALYSIS OF TEE URINE. APPENDIX. § 26. Alkapton. Bodecker * found in the urine of a man forty-four years old, who suffered repeatedly from severe cough and expectoration after typhoid fever, a peculiar substance which had the pro- perty of absorbing large quantities of oxygen and becoming brown in the presence of an alkali. Bodecker calls this body alkapton. The patient at that time suffered great pain, which began from the sacrum, extended to the lower vertebrsB, and thence radiated as lumbo-abdominal neuralgia. The amount of urine in twenty-four hours amounted to about 1,500 cc. (sp. gr. = 1-020 to 1-025), and contained not over one per cent, of sugar. On the addition of potassic hydrate the reddish-yel- low color of the urine became a dark brown from above down- ward, and a large amount of oxygen was absorbed, as Bo- decker proved by a special experiment. A solution of copper was strongly reduced by the urine. Recently Fiirbringer t de- tected alkapton by all of the tests given by Bodecker in the urine of a man twenty-nine years old, who suffered from lung disease. This urine contained no sugar. Carbon 40-00 § 37. Inositb. Formula : £^i^<^^ Crystallized: €.H,A+2H,a [C,,H„0,, + 4H0]. lo^ygg^''" 53.34 [C„H„0,,J j Hydrogen 6-66 100-00 A. Presence. Inosite, until recently, was found only in the muscular tissue, but Cloetta recently found this remarkable carbo-hydrate in the lungs (together with uric acid, taurin, and leucin), very abundantly in the kidneys (together with cystin and hypoxanthin), in the spleen (with uric acid, hypoxanthin, and leucin), and in the liver (with uric acid). Cloetta and Neukomm were able to prove the presence of inosite with certainty in the urine of Bright's disease ; on the other hand, it was not found in * Annal. d. Cliem. u. Pharm., Band 117, p. 98. f Berliner klinische Wocliensclirift, 1875, No. 34. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. US normal urine. W. Miiller and Neukomm found inosite in the brain. Neukomm * found it sometimes in considerable quan- tity in the kidneys as well as in diabetic urine, together with large amounts of sugar, while Vohl saw it occur gradually in a diabetic urine ia the place of sugar. Valentiner was able to separate inosite in considerable quantity from the voluntary muscles of drunkards. Inosite is, however, a not unusual con- stituent of plants also ; Vohl found it in unripe beans {Phaseo- lus vulgaris), W. Gintl t found it in the leaves of the ash, and Marme states that he has found it in the juices of various plants. I found it myself in considerable quantity in the grape juice, in the leaf of the vine, in the must, and in wine. B. Microscopic Properties. Inosite forms for the most part cauliflower-like groups of crystals, but at times it occurs in single crystals which are three or four lines in length. The crystals belong to the klinorhombic system. (Funke, Taf. VI., fig. 6 ; 2« Aufl., Taf. V., fig. 3.) C. Chemical Properties. Inosite loses its water of- crystalliza- tion in the air, and melts at 210° C. Its taste is distinctly sweet ; it is easily soluble in water, and insoluble in ether and alcohol. 1. Melted inosite solidifies when rapidly cooled to pointed crystals ; on slow cooling, on the other hand, it becomes a horny mass. 2. Inosite does not yield alcohol when treated with yeast, but in contact with putrefying cheese it yields lactic and buty- ric acids. The variety of lactic acid which is formed here is paralactic, which yields, on oxidation with chromate of potas- sium and sulphuric acid, malonic acid. (Hilger.)J 3. If a solution of inosite is evaporated with nitric acid on platinum almost to dryness, and the residue is moistened with a little ammonia and solution of chloride of calcium, and the mixture is again evaporated carefully to dryness, a vivid rose- red color arises which is apparent with even one milligram of inosite. (Scherer.) The real sugars do not give this reaction. 4. If inosite is heated with a solution of cupric tartrate in potassic hydrate no reduction takes place^ as in the case of *Canstatt's Jahresber. 1859, II. Abth., p. 91 u. 98. \ Chem. Centralbl. 1869, p. 230. JAnnal. d. Chem., Band 160, p. 338. Digitized by Microsoft® -j^-j^g ANALYSIS OF THE URINE. grape sugar, but a green solution results, from which, after a time, a light greenish precipitate falls, while the fluid above be- comes blue again. If this is filtered off, and the filtrate boiled again, the same change of color is observed. (Cloetta.) 5. Neutral acetate of lead does not precipitate a solution of inosite, but on the addition of subacetate of lead, on the con- trary, especially on heating, a transparent gelatinous precipi- tate occurs, which becomes white in a few moments, and exactly resembles paste. (Excellent means of separating inosite from animal and vegetable fluids.) 6. If a fluid containing inosite is evaporated to a few drops in a porcelain dish, and a small drop of a solution of mercuric nitrate is then added, a yellow precipitate is soon formed. _ If this is spread out as much as possible on the edge of the dish, and again warmed with great care, there remains, as soon as the fluid is all evaporated, if too much of the reagent has not been added, first a whitish-yellow residue, which soon becomes more or less dark red, according to the amount of inosite present. The color disappears on cooling, but reappears again on gently heating. Uric acid, urea, starch, sugar of milk, mannite, glyco- coU, taurin, cystin, and glycogen do not give this reaction. Albumen is colored red, and sugar is colored black, therefore neither of these substances should be present. (Gallois.)* I have frequently made use of this reaction with the best result. To prepare the mercuric solution, one part of mercury is dis- solved in two parts of ordinary nitric acid, it is evaporated to one-half and treated with one and a half parts of water. After twenty-four hours the clear fluid is poured off from the basic salt. D. Detection. As mentioned above, inosite was found in the urine of Bright' s disease as well as in that of diabetes. The urine to be tested for inosite, after any albumen present is first separated, is completely precipitated with sugar of lead solu- tion, filtered, and the warmed filtrate treated with subacetate of lead as long as any precipitate occurs. It is well to concentrate the urine to one-quarter of its bulk on the water bath before precipitation. The subacetate of lead precipitate, which con- tains the inosite combined with lead oxide, is collected after *Zeitschfift f. analyt. Chem., Band 4, p. 264. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. II7 twelve hours, and, after washing, is suspended in water and de- composed with sulphuretted hydrogen. After standing awhile a little uric acid first separates from the filtrate ; the fluid is filtered from it, then concentrated as much as possible, and while boiling treated with three or four times its Yolume of alcohol. If a heavy precipitate results which adheres to the bottom of the glass, the hot alcoholic solution is simply poured off, but if a flocculent non-adhesive precipitate occurs, the hot solution is filtered through a heated funnel and allowed to cool. If after twenty-four hours groups of inosite crystals have de- posited, they are filtered and washed with a little cold alcohol. In this case it is advisable to dissolve the precipitate obtained by the addition of the hot alcohol once more in as little boiling water as possible, and precipitate it a second time with three or four times its volume of alcohol, etc., in order to avoid any loss of inosite. If, however, no crystals of inosite have sepa- rated, ether is gradually added to the clear cold alcoholic filtrate, until a milky cloudiness results on shaking thoroughly, and it is then allowed to stand in the cold twenty-four hours. If too small an amount of ether has not been taken (an excess does no harm), almost all of the inosite present is separated in shining pearly leaflets. (Cooper, Lane.)* Inosite, however, appears to occur only very rarely in urine. Gallois investigated the urine of one hundred and two patients, but found inosite only seven times ; it was found five times in thirty cases of diabetes together with sugar in very variable amounts, and twice in twenty-five cases of albuminuria. § 28. BnJABY Substances. Of the constituents of the bile, the biliary coloring matters as well as the biliary acids occur pathologically in the urine, especially in icterus, phosphorus poisoning, etc. The biliary acids have also been found at times in the urine in pneumonia without the biliary pigments having been discovered at the same time. In fatty degeneration of the kidneys cholesterin appears also to have been found in the urine. *Aiinal. d. Chem. u. Pharm., Band 117, p. 118. Digitized by Microsoft® 1]^3 ANALYSIS OF THE UBINE. Tt n.TAE Y COLORING MATTEES.* A. Presence. The biliary coloring matters occur in the bile and biliary calculi in different modifications ; we meet with them also in the contents of the intestine and in the excrement. Pathologically, especially in the severer forms of icterus, they appear in all of the fluids of the body and may even pass over into the tissues. B. Preparation. Powdered gall-stones are freed from choles- terin and fat by treating them with ether ; the residue is then boiled with water and treated with dilute hydrochloric acid. After washing and drying, the dark brownish green mass is boiled with chloroform as long as it continues to take up any pigment. After the chloroform is distilled off, the residue which remains is treated with absolute alcohol, by which a brown pigment, bilifuscin, is removed, while the red pigment (bilirubin — cholepyrrhin) remains behind. To purify the bilirubin it is repeatedly washed with ether and alcohol, then dissolved in chloroform, the solution allowed to evapo- rate until the pigment begins to separate, when it is precipi- tated by the addition of alcohol. A green coloring matter, bUiprasin, is then withdrawn by alcohol from the residue of the gall-stones which has been left by the chloroform ; this, after evaporation of the alcohol, remains behind, and may be purified by washing with ether and chloroform, and dissolving again in a very little cold alcohol. Finally, after this treatment of the gall-stones there remains a brown body, bilihumin, insoluble in water, alcohol, ether, chloroform and dilute acids. C. Chemical Properties. a. Bilirubin (Cholepyrrhin), CieHigNjOs [CsjHisNsObJ. Bilirubin, besides in the bile, is found in the urine in icterus, etc. It is without doubt identical with the hsematoidin crystals oc- curring in old extravasations of blood. (Hoppe-Seyler.)t If faintly acidified bile is directly shaken with chloroform, bili- rubin remains behind after the evaporation of the chloroform in microscopic red tables and prisms, belonging to the rhombic * Annal. d. Cliem. und Pharin., Band 132, p. 333. Journal f. pr. Chem., Band 104, p. 28, 193, and 401. f Handbuch d. physiol. Analyse, 3'° Aufl., p. 208. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 119 system. It is obtained from gall-stones according to the above method, as an amorphous orange-colored powder. Bilirubin is insoluble in water, very diflScultly soluble in ether and alco- hol, but readily soluble in hot chloroform, benzole, and bisul- phide of carbon. The solutions even on considerable dilution still have a yellow color. 1. An ammoniacal solution of bilirubin gives with chloride of calcium, chloride of barium, acetate and subacetate of lead, and nitrate of silver precipitates which are insoluble in chloro- form. 2. An alkaline solution of bilirubin, treated with an equal volume of alcohol and then with a little concentrated commer- cial nitric acid, gives rise to a magnificent play of colors. The yellow color first changes to a green, then blue, violet, ruby red, , and at last dirty yellow. If shaking is avoided in the perform- ance of this test, all of these colors appear in layers, one above the other. The play of colors also appears without the addi- tion of alcohol, but then a few drops of red fuming acid must be added to the nitric acid. The limit of the reaction first begins at a dilution of from seventy to eighty thousand. This reaction is very elegant and positive if a dilute solu- tion of bromine in alcohol or simple bromine water is added drop by drop to a solution of bilirubin in chloroform. (Maly.) Maly has prepared the final yellow end-product of this re- action, and named it choletelin. Choletelin, however, is not identical with urobilin or hydrobilirubin, as has been affirmed by some. (Maly.)* Characteristic changes of the spectrum correspond to this color-reaction. If the color of the solution approaches the blue modification, a dark absorption band appears between the lines C and D, beginning somewhat nearer D and reaching to about midway between D and E. On dilution the band resolves into two rather indistinct bands, « and /?, which are separated by a narrow clear space situated nearer to D. In the further prog- ress of the reaction these lines gradually diminish in intensity^ but remain apparent up to the beginning of the red modifica- tion. Almost at the same time with a and /?, but usually a little later, a third band, y, appears between b and E almost * Zeitschrift f. analyt. Cliemie, Band 11, p. 353 ; ibid., Band 13, p. 336. Digitized by Microsoft® 120 ANALYSIS OF THE URINE. exactly bounded by this last line, increasing in distinctness in proportion as tlie former bands become paler, and attaining its greatest intensity toward the end of the reaction, but finally it also disappears as the action of the nitric acid progresses. It is interesting that this band, y, corresponds to the absorption band, y, of urobilin. (See Urobilin.) (Jaffe * and Fudakowski.)t 3. A solution of bilirubin in an excess of sodic hydrate be- comes green when exposed to the air. Bilirubin, by taking up oxygen, becomes converted into biliverdin. (Maly.):); b. Biliverdin, £n,Ti,^^,S^, [Os^H.sNjOg]. Biliverdin occurs pro- bably in icteric urine, which has become green after long stand- ing. It dissolves in alcohol with a beautiful green color ; in water, ether, and chloroform it is insoluble. 1. In alkalies biliverdin dissolves with a green color in con- tradistinction to biliprasin, which produces with alkalies a brown. On long standing of the alkaline solution biliverdin finally becomes converted into biliprasin. 2. An alkaline solution of biliverdin reacts with nitric acid the same as bilirubin. The color first becomes blue, then vio- let, red, and lastly dirty yellow. Bilirubin and also biliverdin can be changed to urobilin (hydrobilirubin) on treatment with sodium amalgam. (Maly.) c. Biliprasin, ^^B.^^'SJ^i [CajHjjNjOu]. Biliprasin occurs in small quantity in gall-stones. It also probably occurs in -the bile of the ox and in icteric urine. 1. Biliprasin is insoluble in water, ether, and chloroform. Alcohol dissolves it with a beautiful green color, which becomes brown on the addition of ammonia. (Distinction from biliver- din.) 2. Biliprasin readily dissolves in alkalies. Dilute solutions have the same color as strongly pigmented icteric urine. (On the addition of an acid the brown color becomes green again. Distinction from bilifuscin.) When brown icteric urine on spontaneous acidification, as well as after the addition of an acid, shows the same change of color, it must be concluded that biliprasin is present in preponderant amount. (Stadeler.) * JoTirn. f. pr. Chem., Band 104, p. 401. ■)■ Zeitsctrift f . analyt. Cliem. , Band 8, p. 516. I Journ. f. pr. Cliem., Band 104, p. 34. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 121 3. An alcoholic solution of biliprasin shows the same reac- tion with nitric acid as bilirubin and biliverdin, only the blue is very faint and indistinct. d. Bilifusdn, OieHjoNjOi [CasHjoNjOs]. This brown pigment has been thus far found only in small amount in human gall- stones. It dissolves in alcohol and potassic hydrate with a brown color ; it is precipitated from alkaline solutions in brown flocculi by hydrochloric acid. Bilifuscin behaves the same with nitric acid as the other pigments. D. Detection. A urine which contains biliary pigments in large amount is always strongly tinged deep brown, reddish brown, greenish brown, dark green, or grass green. It foams strongly on being shaken, and colors a piece of filter paper dipped into it yellow or greenish. 1. The reaction for the biliary coloring matters, even when present in very small amount, is most easily obtained by pour- ing into a conical test glass about an inch of concentrated nitric acid, which has been somewhat decomposed by standing in the light, and then carefully covering it with a layer of the urine to be examined by means of a pipette. If biliary pigment is pres- ent, the play of colors begins at the point of contact of the two fluids with a beautiful green ring which gradually rises, and on its lower border a blue, violet, red, and finally yellow ring grad- ually appears. (Kiihne.) It is to be observed here, however, that aU of these colors do not always occur ; violet and green, for the most part, are the most permanent, and the green which first occurs, is alone demonstrative of biliary pigment, since red and violet rings also occur with uroxanthin (indican) and its products of decomposition. (See Uroxanthin.) The presence of albumen by no means disturbs the reaction, since the albumen coagulated by nitric acid, usually carries down at the same time a portion of the pigment, and thus shows the reaction in the most beautiful manner. But at all events the nitric acid ought not to contain too much nitrous acid, since in this case the re- action runs a very rapid course, and the colors are rapidly de- stroyed. In order to avoid a possible confusion between bilirubin and indican, Yitali* performed the test for the biliary pigments * Jahrestericht il. d. Fortschritte der Thierchemie, 1873, p. 149. Digitized by Microsoft® 122 ANALY8I8 OF THE USIJSTB. with nitrate of potassium and dilute sulphuric acid. A single drop of a solution of nitrate of potassium and a few drops of sulphuric acid suffice to produce a beautiful green color in a urine containing only mere traces of bile. After a time the color disappears and becomes yellow at once, without having previously passed through red and blue. 2. The slightest traces of bilirubin can finally be detected in urine, even when the above reaction fails, if large amounts of urine are successively shaken with chloroform, the urine ex- tracted being frequently poured off. The smallest amounts of bilirubin are taken up by the chloroform, and sink with it to the bottom, giving it a yellow color. The supernatant urine is then removed and the chloroform solution covered with a layer of nitric acid which contains nitrous acid. The reaction now takes place from above downward, and shows very brilliantly even with the smallest traces of bilirubin. Another part of the chloroform solution is allowed to evaporate in the air, and the residue is examined microscopically. If bilirubin is present, single reddish-yellow crystals will be readily discovered, which show the color reaction with nitric acid very beautifully under the microscope. The crystals readily dissolve in alkalies ; the solution becomes green on standing exposed to the air.. If in this reaction the chloroform should not readily and quickly settle, the urine is evaporated to dryness on the water bath, the residue is extracted with water, filtered, washed, dried, and the filter cut into small pieces, and repeatedly ex- tracted with chloroform while warm. The golden-yellow solu- tion which is obtained is directly tested for bilirubin with nitric acid or bromine water. Frequently traces of bilifuscin cto still be obtained by boiling alcohol from the residue, which has been exhausted with chloroform. (Schwanda.)* It is not advisable to test an alcoholic solution for biliary pigments with nitric acid, since alcohol also, in the absence of biliary pigments, readily gives a similar play of colors, owing to the formation of hyponitric acid. Finally, if a urine to- gether with biliary coloring matter contains haemoglobin also, the former is precipitated with subacetate of lead, the washed precipitate is decomposed with carbonate of sodium, and the filtrate used for testing with nitric acid. * Zeitschrift f. analyt. Chem., Band 6, p. 501. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF UBINE. 123 3. Cases not rarely occur, however, where the specified re- actions for biliary coloring matters remain absent, even when quite large quantities of pigment are present. According to the investigations of Prussak,* continued fever has an influ- ence on the failure of the reaction; and Huppertf believes that he has found that in such cases the urine contains no bili- rubin but only biliprasin. To detect the latter, according to Huppert, the following method is used : The urine is precipi- tated with milk of lime ; the precipitate is collected, and while still moist is put into a reagent glass, which is then half filled with absolute alcohol, and dilute sulphuric acid is added until the fluid, after shaking, has a distinct acid reaction. It i^ heated, the precipitate filtered off, and the filtrate heated to boiling. The greenish-yellow or yellowish-green color of the fluid then changes quickly to a beautiful dark green, jf an ex- cess of sulphuric acid is present, this change taking place the sooner the more free acid there is. Under certain circum- stances not thoroughly investigated, however, the fluid at times, on continued boiling, becomes dark blue. But this method is not sufficient in all cases, since, according to Fudakowski,:}: products of the oxidation of bilirubin, which form compounds with lime only with difficulty, occur not in- frequently in icteric urines. In that case it is more accurate to precipitate with subacetate of lead or sugar of lead and ammo- nia, and decompose the washed precipitate with oxalic or sul- phuric acid. The aqueous oxalic acid solution is evaporated to dryness, the pigment is extracted from the residue with chloro- form, and the acid solution thus obtained is tested with the spectroscope. The absorption band, y, between b and T, de- scribed above under Bilirubin, will be perceived more or less dark and sharply deflned, according to the concentration. Fre- quently this absorption band can be detected if the urine, after sufficient dilution, is examined directly with the spectroscope in a layer two cm. thick. Investigations by A. Heinsius and P. Campbell § have proved that the icteric urine in these cases contained only cholete- *Centralbl. f. d. med. Wissenschaft.,1867, p. 97. fZeitschrift f. analyt, Chem., Band 6, p. 291 u. 498. izeitschrift f. analyt. Cliem., Band 8, p. 516. § Archly der Physlologie, Band 4, p. 497. Digitized by Microsoft® 134 ANALYSIS OF THE UBINE. lin, the final yellow product of oxidation, whicli is formed in Gmelin's test, and consequently cannot give the well-known change of colors on the addition of nitric acid. The familiar spectral appearance which characterizes the end of Gmelin's reaction can be readily obtained, however, with such urine, especially after acidifying with hydrochloric acid. § 29. BiLIAEY ACBDS. The basis of all of the acids occurring in bile is the non- nitrogenous cholic acid, CjiHjoOs [C48H39O9 + HO]. When pure it crystallizes in colorless shining tetrahedra, rarely in quadri- lateral octahedra. It is not contained in the bile as such, but is united with taurin as taurocholic acid and with glycocoU as glycocholic acid. If cholic acid is heated to 190° or 200° C, or boiled for a long time with acids, it decomposes into dyslysin, Cj^HgeOa [CigHjjOe], and water. Dyslysin is insoluble in water and alcohol ; very slightly soluble in ether. On being boiled with an alcoholic solution of hydrate of potassium it becomes cholic acid again. The barium salt of cholic acid dissolves with much difficulty in cold water, more easily in hot water, and very readily in alcohol. 1. Taurocholic add, Q-^^^t^'SW^, {G-,^~S.i^'SB.fi,i]. This acid, oc- curring in the bile in combination with sodium, has not yet been obtained in a crystalline form. When not absolutely pure it forms a white, amorphous, very hygroscopic powder having an intensely bitter taste, readily soluble in alcohol and water, and insoluble in ether. The barium salt of taurocholic acid is readily soluble in water. If taurocholic acid is treated a long time with potassic hydrate at a boiling temperature, it decomposes into cholic acid, which combines with potassium, while taurin is set free ; if hydrochloric acid is used instead of hydrate of potassium, it splits up in the same manner; the cholic acid, however, is not separated as such, but is changed partially into dyslysin by the action of the hot hydrochloric acid. The separated taurin, e^HjSNO, [CjHjS^lSrOJ. crystallizes in colorless, regular, six-sided prisms with four- and six-sided ter- minations. (Funke, Taf. III., fig. 4 ; 2 = Aufl., Taf. V., fig. 1.) This body contains nitrogen, and is characterized by containing Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. igg twenty-five per cent, of sulpliur. Taurin is readily soluble in water, less readily in alcohol ; the solutions have a perfectly indifferent behavior toward vegetable colors. Taurin is most readily obtained by evaporating fresh ox-bile free from mucus with strong hydrochloric acid, when the dys- lysin, etc., separates. The chloride of sodium is allowed to crystallize from the strongly concentrated fluid, the mother liquor is evaporated somewhat further, and the taurin is preci- pitated by admixture with double its volume of strong alcohol. It is obtained pure in the form of beautiful large crystals by re crystallization from water. 2. Glycocholic acid, &,eHj3N"a6 [CsjHjjNOn+HO]. This occurs also in normal bile in combination with sodium. Glycocholic acid crystallizes in the form of very fine needles (Funke, Taf. rV., fig. 6 ; 2'« Aufl., Taf. VIIL, fig. 5), wherein it essentially differs from taurocholic acid. It is quite readily soluble in hot water and alcohol, but on the contrary is very slightly soluble in ether. It does not crystallize from the alcoholic solution, but separates as a resinous mass on evaporation ; if, however, the solution is mixed with water, it gradually separates in the crys- talline form on evaporation. The barium salt of glycocholic acid is readily soluble in water. By boiling with potassic hy- drate, baryta water, or hydrochloric acid, it suffers a similar decomposition as taurocholic acid, cholic acid or dyslysin being set free and glycocoll separated. Glycocoll, G2H5NO2 [C4H5NO4], is formed by treating gluten with mineral acids, from monochloracetic acid by the action of ammonia, and finally from hippuric and uric acids by heating with hydrochloric acid ; from uric acid at a temperature of 160° to 170° C. Glycocoll forms colorless rhombic prisms (Funke, Taf. in., fig. 5 ; 2'= Aufl., Taf. IV., fig. 1), which are hard and permanent in the air, and taste almost as sweet as cane sugar. This body contains nitrogen but no sulphur. A. Emmerling * has discovered a new method for the synthe- sis of glycocoll. If cyanogen gas is treated with concentrated hydriodic acid, glycocoll is formed according to the following reaction : 2(GN) + 5IH + 2H5O =e,H5NO, + NH4I + 1,. *Ber. d. d. chem. Gesellscli., Band 6, p. 1351. Digitized by Microsoft® 126 ANALYSIS OF THE UBINE. Chemical Properties.—!. All of the biliary acids when com- bined, as well as free cholic acid also, react in a peculiar char- acteristic manner with sulphuric acid and sugar, which distin- guishes them from the coloring matters, as well as from taurin and glycocoU. If the aqueous solution of any one of the biliary acids is treated with a few drops of a solution of sugar and then with concentrated sulphuric acid until the mixture has a tem- perature of 50° to 70° 0., the fluid becomes colored a beautiful purple violet. (Pettenkofer.) Oleic acid and albumen give a similar reaction. To distinguish this from similar reactions which are obtained with albuminous bodies, oleic acid and amyl alcohol, the spec- tral appearances of the biliary acid reaction can be used. If the fluid is diluted, so that only the violet is absorbed, an absorption band on the line F and a second between D and E, nearer E, appear. In concentrated solutions only the second band can be seen. (L. Schenk.)* Even the smallest traces of biliary acids can be detected by means of this reaction in the following manner : A few drops of the fluid to be tested are evaporated to dryness on the water bath in a porcelain dish ; a small drop of a solution of sugar (one gram of sugar in half a liter of water) and an equally small drop of concentrated sulphuric acid are added to it. It is then heated a few minutes on the water bath, and the violet-red color soon forms on the edge. At this moment the dish is removed from the water bath and allowed to stand quietly, when the reaction will increase considerably in intensity. In this manner I have succeeded in detecting with absolute certainty, by the most beautiful reaction, one four-hundredth to one six-hundredth of a milligram of the sodium salt of the biliary acids. On heating on the water bath, the reaction occurs much more positively than by evaporating over a free flame, as recommended by Neukomm. 2. A second very delicate reaction is the following: The biliary acid or salt is covered with a small amount of concen- trated sulphuric acid, moderately warmed, and then water is added. The resinous flakes which deposit are separated from the acid, washed a few times with water without completely removing the sulphuric acid, and gently heated in a porcelain * Jaliresbericlit u. d. Fortschritte d. TMeroliemie, Band 3, p. 333. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 127 dish until they become colored. Then the residue is taken up with a very little alcohol, and the green solution is evaporated with constant turning, so that the inner surface of the dish be- comes covered with a deep indigo-colored coating, even when only a very little acid has been used. If the biliary acids are mixed with foreign matters, or if the sulphuric acid is allowed to act a long time, or at too high a temperature, the coating of pigment appears green. According to my experience, however, this reaction, even with the modification proposed by Von Bogomoloff,* is far less delicate and accurate than Pettenkofer's. Detection. — 1. A portion of urine (300 to 500 cc.) is evaporated on the water bath almost to dryness, and the residue is ex- tracted with ordinary alcohol ; the alcoholic solution is evapo- rated again, and the residue extracted with absolute alcohol. The solution thus obtained, now tolerably poor in salts, is freed from alcohol, the residue is taken up with a little water, the so- lution treated with subacetate of lead, of which an excess is to be carefully avoided, and the precipitate, after standing about twelve hours, is collected, washed, and gently dried between blot- ting paper. In order to remove as much as possible of other substances mixed with the lead precipitate, the lead compound with the biliary acid is extracted with boiling alcohol, the solu- tion is evaporated to dryness after the addition of carbonate of sodium, and the residue is treated with absolute alcohol in order to obtain the sodium compound with the biliary acid. The sodium salt thus obtained always contains, in addition to the biliary acids, small amounts of a resinous constituent of the urine, which is colored brownish red by sulphuric acid, at times also pale blue or violet, and on heating, after the addition of sugar, reddish or yellowish brown. This color is seldom so deep as to conceal the biliary reaction ; but if this is found to be the case, after a preliminary trial, the biliary acid is once more precipitated from the aqueous solution by subacetate of lead, the precipitate is collected after standing awhile and decomposed, as above, with carbonate of sodium. Then two or three drops of a solution of sugar (one part of sugar to four parts of water) are added to the aqueous solution of the *Zeitsolir. f. analyt. Chem., Band 9, p. 148. Digitized by Microsoft® 128 ANALYSIS OF THE URINE. sodium compound made as concentrated as possible, and after- ward pure concentrated sulphuric acid, free from nitric and sulphurous acid, is added. Care is to be taken here that the temperature does not rise much above 70° C. If biliary acids are present the fluid first becomes cloudy, then clear, and at the same time yellow, but shortly afterward it changes to a pale cherry-red, dark carmine-red, and at last beautiful purple violet. The test becomes considerably more delicate, if it is per- formed with the modification given above ; one four-hundredth of a milligram of the sodium salt of the biliary acid can be detected with absolute certainty by this procedure. The pres- ence of biliary acids can be considered as proved only when the fluid becomes colored not only red, but also distinctly purple violet. The biliary acids may frequently be successfully detected by the following very simple method : A piece of filter paper is dipped into the urine to be tested after a little cane sugar has been previously added, and then the paper is allowed to dry. If a drop of pure concentrated sulphuric acid is then placed on the paper by means of a glass rod, there appears in about a quarter of a minute a beautiful violet color which is quite distinct, especially with transmitted light. This method is, in fact, very delicate, so that three one-hundred-thousandths (O'OOOOS) of a gram of biliary acid gives the reaction in a most beautiful manner. Normal urine does not give this reaction. If a large amount of cane sugar is present, a reddish or brown color, which, however, cannot be confounded with Pettenkofer's reaction, appears. (G. Strassburg.)* 2. According to Hoppe the urine is directly precipitated with subacetate of lead and a little ammonia, the precipitate washed with a little water, and then boiled with alcohol and filtered while hot. The alcoholic filtrate is treated with a few drops of sodic hydrate solution, evaporated to dryness, and the so- dium salt of the biliary acids extracted from the residue by boiling with absolute alcohol. The alcoholic solution is evapo- rated to a small volume, and treated in a closed flask with ether, by which the biliary salts are precipitated and often * ArcMv der Physiologie, Band 4, p. 461. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF UBINE. 129 crystallize out after long standing. In the employment of the test with sugar and sulphuric acid it is not necessary to wait, however, until the precipitate caused by ether has become crystalline, but the resinous precipitate dissolved in a little water can be immediately used for this purpose. If, however, we wish to determine whether cholic acid is present in addition to glycocholic and taurocholic acids, the resinous precipitate is allowed to crystallize under ether, the ether is then poured off, the crystals dissolved in a little water and treated with a drop of chloride of barium solution. If a precipitate takes place, the presence of cholic acid, whose barium salt is very difficultly soluble in water, is demonstrated. (Hoppe-Seyler.) 3. According to Dragendorff, the biliary acids can be with- drawn from the urine by shaking with chloroform. 120 to 150 grams of urine are acidulated with a few drops of hydrochloric acid, and shaken with 30 grams of chloroform for at least an hour. The urine is separated by decanting, and the chloroform, which is colored brown by the precipitation of the extractive and coloring matters, is treated with six to eight cc. of absolute alcohol, which takes up the cloudy flakes while the chloro- form becomes perfectly clear again. It is then filtered, when a thick jelly frequently forms on the filter which contains the chloroform, and allows nothing more to flow through. If this jelly is detached from the filter, however, by stirring with a glass rod, the chloroform and alcohol pass through rapidly. The chloroform separated from the alcohol is then allowed to evaporate on watch glasses, and the residue is used for the test with sugar and sulphuric acid. By this method Yogel* found biliary acids in the urine of eight different healthy per- sons. To decide the question whether biliary acids really belong to the normal constituents of urine, Dragendorff then examined 1,000 cc. of the urine of each of ten healthy persons, varying in age from eight to fifty-five years, by the method given above under Detection. The sodium salt of the biliary acid which remained after the evaporation of the alcoholic solu- tion was dissolved in acidulated water, and the free biliary acid transferred to chloroform by shaking with it. The residue which remains after evaporation of the chloroform serves for * Zeitschrift f. analyt. Cliem., Band 11, p. 467. 9 Digitized by Microsoft® 230 ANALYSIS OF THE UBINE. Pettenkofer's test. By working witli one hundred liters of nor- mal urine, according to the method given, Dragendorff suc- ceeded in preparing the biliary acids in pure form ; a part separated as the sodium salt of the biliary acids in microscopic crystals, and the elementary analysis gave corresponding re- sults. Dragendorff obtained from one hundred liters of normal urine O'T to 0-8 gram of biliary acids. It is always advisable to take large quantities of urine for working, since always only very small amounts of the biliary acids go over into the urine, even when the icterus is very- intense. Cholesterin has sometimes been found in the urine in fatty degeneration of the kidneys, mixed with other fats. The sedi- ment, consisting chiefly of fat globules, was collected, dried on a water bath, and digested with a mixture of alcohol and ether. The filtered and concentrated extract deposited crystallized cholesterin, which, on account of its microscopic form, is not readily confounded with any other substance. (Funke, Taf. VI., % 1-) If a little cholesterin is dissolved in about two cc. of chloro- form, and then about an equal volume of concentrated sul- phuric acid is added and the fluid shaken, the chloroform solution becomes rapidly colored blood red, and then beautiful cherry red or purple, a color which remains unchanged for days. The sulphuric acid, standing under the chloroform at the same time, has a strong green fluorescence. If some of the chloroform solution is poured into a saucer, it rapidly becomes blue, then green, and finally yellow, due to the absorption of water. (Salkowski.) The reaction is elegant and delicate. § 30. Lactic Acid. Formula : €,H„0, Carbon 40-00 rOTTm ) Hydrogen 6-67 LUe±±eUeJ ( Qxygen 53-33 100-00 A. Presence. Ordinary lactic acid from fermentation occurs partly free, partly in combination, in the juices of the stomach and contents of the intestine, and in fermenting diabetic urine Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 131 as well as in sour milk. Paralactic acid occurs in the muscular juice of man and animals, in tlie bile, as well as very abundantly in the urine after phosphorus poisoning.* It has also been found in the urine in acute atrophy of the liYer,t trichinosis,^ and osteomalacia.§ Whether the lactic acid contained in dif- ferent glandular fluids and transudations is ordinary or para- lactic acid, requires still more accurate investigations. Lehmann has found that when the excretion of oxalate of calcium and uric acid is increased, lactic acid is always found in the urine. Hoppe-Seyler obtained lactic acid, together with brenzcate- chin, by the action of alkalies on sugar. According to the investigations of Wislicenus,! the lactic acid of flesh is a mixture of two different acids, the principal one of which turns the plane of polarized light toward the right, and forms well-crystallizable salts, while the second acid occurs in less amount and possesses only a slight power of crystallization. Wislicenus found this second acid in ordinary meat in greater amount than in Liebig's meat extract, and in stiU greater relative amount in various pathological fluids of the animal and human body, such as urine, ascitic fluid, bile, etc. The optically active lactic acid of meat yields on oxidation with chromic acid no malonic acid; it is not, therefore, ethylen- lactic acid, with which the second is probably identical, which does yield malonic acid together with carbonic and oxalic acids on being oxidized with chromic acid. B. Okemical Properties. In the pure concentrated condition lactic acid is a colorless and odorless syrupy fluid, which hith- erto has never been crystallized, and has a strongly acid taste. It is soluble in water, alcohol, and ether, and attracts water from the air. At 140° it becomes free from water; but at a higher temperature it splits up into lactid, carbonic acid, and other compounds. There are no characteristic tests for lactic acid, but the * 0. Schultzen u. L. Eiess : Ueber acute Phosphorvergiftung und acute Leberatrophie. ■f Ibid. X Berichte d. deutsch. chem. Gesellsch., 1871, Heft 3. § Moers u. Muck : Deutscbes Archiv f . klin. Med. , Band 5, p. 485. 1 Annal. d. Chem. und Pbarm. 167, p. 346. Tagblatt der 46 Versammlung deutsch. Naturf orscher u. Aerzte, Wiesbaden. Digitized by Microsoft® 133 ANALYSIS OF THE URINE. microscopic appearance of some of its salts is distinctive and very important for its recognition. 1. Lactate of Calcium. This is formed by dissolving carbo- nate of calcium in lactic acid. It crystallizes under the micro- scope in fine needles collected in tufts. Of these tufts two are always so placed with their pedicles toward each other that they resemble pencils which run into each other. (Punke, Taf. II., fig. 1; 2'^ Aufl., Taf. I., fig. 4.) Ordinary lactate of calcium contains 29 '22 per cent, of water of crystallization, while paralactate of calcium contains 24'83 per cent. 2. Lactate of Zitic. This is formed by boiling pure oxide of zinc with lactic acid. The crystals, when separated rapidly under the microscope, appear in the form of spherical groups of needles, and may be readily obtained in great beauty. If, however, we allow a drop of a solution of lactate of zinc to eva- porate gradually, the crystals first appear club-shaped, trim- cated at both ends. These crystals gradually increase, the ends become smaller, while the middle becomes bellied. This peculiar bellied, barreled, or clubbed shape is very distinctive and characteristic of lactate of zinc. (Funke, Taf. 11. ; 2" Aufl., Taf. I., fig. 5.) Ordinary lactate of zinc contains 18-18 per cent, of water of crystallization; paralactate, however, contains 12-90 per cent. 0. Detection. The urine, which must be fresh, is evaporated almost to dryness on- the water bath, and the residue treated with an alcoholic solution of oxalic acid. The oxalates which are thus formed, as well as the oxalate of urea, remain undis- solved, while the lactic acid, together with the phosphoric and hydrochloric acids, are in solution. The fluid is digested with hydrate of lead, evaporated to dryness, and the residue extracted with absolute alcohol which will dissolve the lactate of lead. The flltrate is treated with sulphuretted hydrogen, after filter- ing evaporated on the water bath to a syrup, and shaken with ether, which, after evaporation, leaves the lactic acid more or less pure. This is dissolved in a little water, boiled with zinc- oxide, filtered, and allowed to crystallize gradually on an object glass. The lactate of zinc is readily recognized by its barrel and club-shaped crystals, especially those which increase in size. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF UBINE. 133 Scherer uses the following method for detecting lactic acid, whicli yields excellent results in every way : The extract which is to be tested for lactic acid is dissolved in water, precipitated with baryta water, and filtered. Any volatile acids present are removed from the filtrate by distillation with a little sulphuric acid, and the residue is allowed to stand several days with strong alcohol. The acid fluid is evaporated with a little milk of lime to dryness, the residue is dissolved in hot water, and while still warm is filtered from the excess of lime and sulphate of calcium, a stream of carbonic anhydride is conducted into the filtrate, it is heated again to boiling, filtered from the pre- cipitated carbonate of calcium, the fluid evaporated to dryness, the residue warmed with strong alcohol, filtered if necessary, and the neutral filtrate set aside for a few days for the lactate of calcium to separate. If so little lactic acid is present that no crystals separate, it is evaporated to a syrup, mixed with strong alcohol and allowed to stand, when a usually dark deposit of extractive matter and lime is formed. The fluid is then poured into a closed vessel, and a small amount of ether is gradually added. Even traces of lactate of calcium, which can be readily recognized under the microscope, separate. Large amounts of lactic acid, such as occur in the urine after phosphorus poisoning, are separated in the following manner : The urine is strongly concentrated on the water bath, and then completely precipitated while warm with 95 per cent, alcohol. After twenty-four hours the clear alcoholic solution is decanted from the sediment, evaporated to a syrup, acidified with dilute sulphuric acid, and shaken with renewed quantities of ether as long as it takes up anything. After distilling off the ether the residue is dissolved in water, filtered, precipitated with sugar of lead solution, filtered, the filtrate treated with sulphuretted hydrogen, filtered again, and the acetic acid expelled by repeated evaporation on the water bath. The colorless fluid thus obtained is saturated with carbonate of barium, filtered, evaporated to a syrup, and the lactate of barium precipitated with absolute alcohol. The mass, which is at first doughy, is changed into a granular crystalline powder by continued digestion with abso- lute alcohol, and its aqueous solution is accurately precipitated with sulphate of zinc, so as to form lactate of zinc. The zinc salt after evaporation separates from the filtrate in crystals Digitized by Microsoft® 134 ANALYSIS OF THE URINE. with 12-9 per cent, of water of crystallization, and 26-74 per cent, of zinc* § 31. Volatile Fatty Acids. Of the volatile fatty acids there have thus far been found in the urine formic, acetic, propionic, butyric, and valerianic acids. I. Formic Add, QTL,Q, [O2H4O,] . Formic acid, besides in ants, occurs also in the poison-organs and stings of certain insects. It was, moreover, found in the sweat, in the fluid of the spleen, pancreas, thymus gland, muscles, and brain. Finally it occurs in the blood as well as in the urine, according to Buliginskyt and Thudichum.| It is formed by the decomposition of the coloring matter of the blood by acids ; also, according to Thudi- chum, by the decomposition of urochrom. Somewhat larger amounts of formic acid appear to occur in the urine of leukae- mia. (E. Salkowski.) GJwmical Properties. Pure formic acid is a colorless fluid of intense piercing odor, which freezes at 0°, boils at 100° 0., and mixes with water and ailcohol in every proportion. 1. Ferric chloride causes a blood-red color in neutral solu- tions of formiates. 2. Nitrate of silver does not precipitate free formic acid; it precipitates formiates only when in concentrated solutions. For- , miate of silver becomes black in the cold ; on heating complete reduction immediately takes place. This reduction, in which the fluid is colored black, takes place even when the solution is so dilute that no precipitate occurs, or when free formic acid is present. 3. If a solution of formic acid or one of an alkaline formiate is treated with mercuric chloride, and heated to 60° or 70° C, mercurous chloride (calomel) separates, and after more pro- longed boiling the metal also. Free hydrochloric acid prevents this reaction. 4. On heating with concentrated sulphuric acid formic acid decomposes into carbonic oxide and water. * 0. Schultzen and L. Riess, loo. cit. f Hoppe-Seyler, Med. chem. Mittheilungen , Heft 3, p. 340. if The Journ. of the Chemical Society, vol. 8, p. 400. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 135 n. Acetic Add, GoH^Oj [O4H4O4]. Acetic acid appears in tlie nrine as soon as it has commenced to ferment. It also occurs in quite an amount during the fermentation of diabetic urine. It has been found also in muscular juice and in the fluid of the spleen, in leukaemic blood, in the contents of the stomach and vomitus together with free lactic acid in cases of disturbed digestion, in the sweat, and in the bile. According to Thudi- chum, acetic acid is also a product of the decomposition of urochrom. Chemical Proj)erties. In the concentrated state acetic acid is a colorless fluid with an intensely acid smell and a sharp caus- tic taste, whose boiling point is 119" C. At 5° C. it crystallizes ; above 16° C, however, it is fluid. Acetate of sodium crystal- lizes readily. 1. Ferric chloride gives in solutions of an acetate a blood-red color of acetate of iron. 2. Nitrate of silver gives in neutral solutions of an acetate a white crystalline precipitate of acetate of silver, which dissolves in hot water without reduction, and on cooling crystallizes out again. 3. On heating an acetate with alcohol and sulphuric acid the characteristic odor of acetic ether is evolved ; with sulphu- ric acid alone the piercing odor of acetic acid is obtained. Crystallized acetate of sodium contains 22 '9 per cent, of so- dium, the barium salt 53 "8 per cent, of barium, the silver salt 64"67 per cent, of silver. m. Propionic Acid, G^B.^O, [CbHsOj]. Propionic acid is said to occur in the fluids of certain glands, in the sweat, in the gas- tric juice, 'in the vomitus in cholera, and in fermenting diabetic urine as well as in the bile. Salkowski* mentions that he has found it also in normal urine. Chemical Properties. The concentrated acid is a colorless oily fluid, which boils at 138° C, has a peculiar odor and is readily soluble in water. The addition of a large amount of chloride of calcium separates it from its aqueous solution as an oily fluid. 1. Nitrate of silver gives in concentrated solutions of propio- nates a whitish precipitate, which is soluble with partial reduc- * Aichiv d. Physiolog., Band 3, p. 361. Digitized by Microsoft® 136 ANALYSm OF THE URINE. tion in boiling water. "When the solution cools the propionate of silver crystallizes in -white, shining, microscdpic'rosettes of needles. 2. The propionate of barium is readily soluble in water, and crystallizes in octahedral prisms with oblique terminal surfaces. Propionate of silTsr contains 59'67 per cent, of silver, and the barium salt 4841 per cent, of barium. IV. Butyric Acid, OJ^sOj [CsHs04]. Butyric acid occurs in the sweat, in the contents of the stomach and in the vomitus in disturbances of the digestion, in the contents of the large intes- tine, in the solid excrement, and in the urine. It has also been found in the blood, juice of the spleen, contents of ovarian cysts and in the muscular juice. Lehmann found it at times in the urine of pregnant women, but also in that of women not preg- nant ; he has also frequently found butyric acid in the urine of men. If diabetic urine is treated with powdered chalk, and the mixture is allowed to ferment at a temperature of 35° to 40° C, a considerable amount of butyric acid forms (Scherer, written communication), while at a lower temperature, without the addition of chalk, it often contains only acetic acid. Chemical Properties. The pure acid is an oily, colorless fluid, which smells very disagreeably like rancid butter, and which boils at 157° C. It is soluble in all proportions in water, alco- hol, and ether. Chloride of calcium separates it from the con- centrated aqueous solution as an oily layer of fluid. Most of the salts of butyric acid are soluble in alcohol and water, and on the addition of mineral acids develop the disa- greeable odor. 1. Butyric acid forms compounds with the alkalies, alkaline earths, and the true metallic oxides. The compounds with the alkalies are deliquescent and uncrystallizable, while the other salts can be readily obtained in a crystalline form. a. Butyrate of Barium. This can be .produced by saturating butyric acid with baryta water. If the compound is crystallized rapidly from such a solution it separates in the form of a pellicle shining like fat on the surface of the fluid, and appears under the microscope mostly in the form of close heaps of crystalline plates not accurately distinguishable. If, however, the solution of butyrate of barium is allowed to evaporate spontaneously, long, Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 137 flattened, completely transparent prisms form, wMcli lie together for tlie most part in stellate rosettes. This salt dissolves readily in water; the solution blues reddened litmus paper. (Funke, Taf. I., fig. 8 ; 2'° Aufl., Taf. II., fig. 2.) Butyrate of barium con- tains 44'05 per cent, of barium. b. BletaUic Butyrates are formed by precipitating a concen- trated solution of the butyrate of an alkali with the solutions of the various metallic oxides. Thus the nitrate of silver produces a yellowish-white crystalline precipitate of butyrate of silver, which is almost insoluble in cold water and contains 55 '38 per cent, of metallic silver. V. BaMrianic Acid, GsHjoOj [OioHjoOi], Baldrianic acid has been found in the urine in typhoid fever, variola, and acute atrophy of the liver. It is formed very abundantly by the putrefaction of impure leucin in contact with ammonia. Chemical Projoerties. The pure acid is a colorless, oily fluid of penetrating odor, which boils at 175° C, and is readily soluble in alcohol and ether. It requires thirty parts of water, how- ever, to dissolve it. 1. The baldrianates of the alkalies are easily soluble and not crystallizable, the other salts crystallize in shining crystalline scales. a. Baldrianate of barium crystallizes either in transparent prisms which disappear at 20° to 25° 0., or more frequently in plates similar to those of cholesterin, which are readily soluble in water, but difficultly soluble in alcohol. This salt contains 40'4:1 per cent, of barium. b. Baldrianate of silver crystallizes in fine plates which shine like silver, and are difficultly soluble. It contains 51-67 per cent, of silver. Detection of the Fatty Acids. To separate the volatile fatty acids, as large an amount of urine as possible must be used. It is strongly acidulated with phosphoric acid, and then distilled as long as the distillate shows any traces of an acid reaction. If the residue in the retort becomes too concentrated, it is allowed to cool, water is added, and the distillation commenced anew. The different distillates are then united, saturated with carbonate of sodium, and evaporated to dryness. The residue is extracted with absolute alcohol, filtered, the filtrate evapo- rated to dryness, and the saline residue now obtained after the Digitized by Microsoft® 138 ANALT8I8 OF THE UBINE. addition of phosplioric acid, is subjected to distillation as long as tlie fluid wliich passes over has an acid reaction. The dis- tillate is first tested with nitrate of silver or mercuric chloride for formic acid. If this is present, it is destroyed by boiling with mercuric oxide, the fluid is saturated with carbonate of sodium, filtered, evaporated, and allowed to stand for a time to crystallize. If acetic acid is present, the acetate of sodium soon crystallizes, as, for example, in old diabetic urine, from which it separates abundantly, and is easy to recognize as such. If the acetate of sodium has separated, the mother liquor is acidulated again with phosphoric acid and subjected anew to distillation. The distillate which is now obtained is treated with baryta water in excess, carbonic acid is conducted into it until it has a neutral reaction, it is heated to boiling, filtered, and evaporated to a small volume for crystallization. The propionate of barium is the most soluble of the barium salts, the butyrate is the least soluble. Analysis of the barium salt obtained will give information of the nature of the acid if only one of the higher members is present, but if several are present at the same time, several barium salts must be obtained by fractional crystallization, and the amount of barium con- tained in each must be determined, since the material at hand would probably never suffice for producing the different acids in a state of purity. In using large amounts of urine benzoic acid also is almost al- ways obtained in the distillate, due to the decomposition of the hippuric acid. It separates especially during the second distil- lation in crystalline plates, which remain partly adhering to the condenser and partly floating on the surface of the distillate, and can readily be recognized as such. § 32. Benzoic Acid. Formula: G,HA f Carbon 68-85 O.^HeO. i Hydrogen 4-92 L Oxygen 26-23 100-00 A. Presence. Benzoic acid occurs in the urine of herbivora probably after hard work or after wretched fodder. It is formed Digitized by Microsoft® ABNOBMAL CONSTITUENTS OF UBINE. 139 constantly in the putrefying urine of these animals, as well as in that of human beings, where it is formed by the decomposi- tion of hippuric acid. Benzoic acid is the non-nitrogenous component of hippuric acid, for, as we have seen above, benzoic acid in the economy takes up the elements of glycocoU and ap- pears again in the urine as hippuric acid. Conversely hippuric acid in contact with putrefying matters is decomposed imme- diately into benzoic acid and glycocoU again. Moreover, benzoic acid occurs as a product of the decomposition of many animal substances, especially protein bodies, gluten, etc. Hilger found in the urine passed after partaking largely of asparagus, benzoic acid together with hippuric acid, succinic acid, and an increased amount of ammonium salts. B. Microscopic Properties. Sublimed benzoic acid appears in the form of colorless, fine, shining needles and leaflets, while that obtained from its solutions is in scales, small prisms, or six-sided needles, whose primitive form is a right rhombic prism. On cooling aqueous solutions, the crystals appear un- der the microscope always connected together, sometimes also in tables of exactly 90° overlapping each other ; in rare cases, one angle becomes truncated, but in such a way that the two angles are 135°. (Funke, Taf. I., fig. 6; 2'° Aufl., Taf. II;, fig. 6.) C. Chemical Properties. At 240° C. benzoic acid sublimes un- decomposed, its vapors irritate the throat and excite cough- ing. It is difficultly soluble in cold water, more easily in hot water; alcohol and ether take it up with toleralale easp. Its solutions redden litmus. Benzoic acid volatilizes with aqueous vapor ; therefore, only neutral solutions can be concentrated by evaporation. 1. The benzoates are mostly soluble in water, only those of the heavy metals are difficultly soluble. The alkaline ben- zoates dissolve in alcohol. 2. Strong acids decompose benzoates when in solution with the separation of benzoic acid in white shining scales. 3. Chloride of iron gives in a solution of alkaline benzoates a brownish-yellow precipitate of benzoate of iron, which is de- composed by ammonia with the separation of ferric hydrate and formation of benzoate of ammonium. Benzoate of iron treated with a little hydrochloric acid dissolves with the sepa- ration of benzoic acid. Digitized by Microsoft® 140 ANALYSIS OF THE URINE. 4 Free benzoic acid in a mixture of alcohol, ammonia, and chloride of barium solution, causes as little precipitation as the alkaline benzoates. (Distinction from succinic acid.) 5. If benzoic acid is evaporated with a little nitric acid by boiling in a small porcelain dish, an odor of bitter almonds or nitrobenzol is evolved when the residue is strongly heated. D. Detection. The neutralized urine is evaporated to the consistence of an extract, and this is extracted with alcohol; after evaporation of the alcohol, benzoic acid separates in crys- talline form on the addition of a stronger acid. If its amount is very small, so that no crystals are obtained in this manner, the mass is extracted with ether which is then left to sponta- neous evaporation ; benzoic acid is separated from the ethereal extract in a crystalline form by water. The crystals are exam- ined chemically and microscopically. If succinic acid should be present at the same time, the acids are converted into their barium salts, and these are treated with boiling alcohol. Succinate of barium thus remains behind undissolved, while benzoate and any hippurate of barium present are dissolved, Benzoate of barium remains after evaporating the hot filtered alcoholic solution, and the benzoic acid is readily separated from this by hydrochloric acid. If hippuric acid is present, it can be easily separated by treating with ether, which dissolves the benzoic acid very readily. If, moreover, decomposed urine is treated as given under the head of Detection of the Volatile Fatty Acids, § 31, at the end of the second distillation, especially when it is pushed a little further, white scales and leaflets will be observed, which for the most part remain in the condensing tube, and are readily recognized as benzoic acid. § 33. Fats. A. Presence. Urine containing fat is hot a very frequent ap- pearance. The peculiar milky urine which sometimes occurs {urina chylosa), frequently owes its cloudiness and color not to fat which is in suspension, but, as Lehmann declares, to a large number of pus corpuscles ; but Beale records a case of milky urine abounding in fat which was passed for months in the morning by a woman fifty years old. This urine became per- Digitized by Microsoft® ABNORMAL CONSTITUENTS OF UBINE. 141 fectly clear after shaking witli ether. Quantitative estima- tion showed in 1,000 parts 13-9 grams of fat. Beale believes that the chylous character arose from a separation of chyle by the kidneys. Beale found cholesterin also in the fatty cells passed with the urine in fatty degeneration of the kidneys, which, dissolved in other fats, could be obtained by first ex- tracting with alcohol and subsequent crystallization. Galac- turia appears to occur with special frequency in certain tropical regions. A series of cases is recorded in Schmidt's Jahrbuch, 1863, 12, p. 274 Eggel* records a similar case of chyluria. 390 cc. of this urine resembling milk yielded to ether 2-68 grams of fatty substance, in which the fatty acids, that is, neutral fats, choles- terin (?) and lecithin or the products of their decomposition, neurin and phosphoric acid, were detected. B. Microscopic Properties. Free fat is readily recognized un- der the microscope. With regard to the fat drops, they appear as flat disks, which possess a very great refractive power ; they have dark, tolerably irregular contours. The single drops are frequently seen under the microscope to flow together, where- by they may be distinguished from fat cells which are per- fectly spherical. Fat cells have a round, smooth, sometimes polyhedral form from mutual pressure. The surface also has a strong refractive power; with transmitted light the contours are sharp and dark, but when examined by reflected light the borders appear shining like silver and the centre of the cells is whitish. It is easy to burst such cells by pressure, their contents then flow out, and the surface assumes a more or less wrinkled appearance. (Funke, Taf. VII., fig. 3 und 4 ; 2'° Aufl., Taf. XIY., fig. 3 und 4) C. Detection. Since fat occurs in urine only rarely, and also only in very small amount, we naturally do not think of a separation and individual recognition of the different com- pounds, and must content ourselves with finding and recogniz- ing it as such. The microscopic appearance is so characteristic and significant that every one who has once seen a fat drop will recognize it again at the first glance. Our first attempt, therefore, is always to recognize under the microscope the *Centralblattf. d. med. Wissenschaf t., 1870, p. 121. Digitized by Microsoft® 142 ANALYSIS OF THE UBmB. above-mentioned qualities. If this does not succeed, a portion of the urine is evaporated to dryness on the water bath, the residue is exposed for a time to a temperature of 110° C, and is treated with successive small portions of ether as long as this takes up anything. This ethereal solution will now contain all the fat, and will leave it behind on evaporation, which is beat performed in a small cylindrical glass. The residue can then be tested first microscopically and then chemically, as far as the material suffices. The production of greasy spots on fine paper, as well as the behavior on being heated (development of acro- lein), does not admit of a confusion with any other body. Chylous urine for the most part contains, in addition to greater or less amounts of fat, which is held in the form of an emulsion byHhe albumen present at the same time, lymph and blood corpuscles. A creamy layer frequently collects on the surface, and after a shorter or longer time fermentation occurs, when fibrinous coagula soluble in a solution of nitre separate. These fibrinous coagula are either delicate white, and fill the whole fluid, or they form clumps of a light or dark red color, some- times dense, sometimes delicate and mucus -like, which are also soluble in nitre.* § 34. Sulphuretted HroEOGEN. Sulphuretted hydrogen sometimes occurs in the urine, but only in rare cases. Its presence is readily recognized by the fact that a piece of paper moistened with a sugar of lead solution is 'blackened. The experiment is best performed in the following manner : A small beaker is half filled with the urine to be tested for sulphuretted hydrogen, and it is then covered with a watch glass, on the lower surface of which a small piece of lead paper has been fastened by moistening with a drop of water. According to the amount of sulphuretted hy- drogen present, the paper will soon become brown or black, especially if the urine is slightly warmed. Sulphuretted hydro- gen is also easily recognized by its stinking odor like that of rotten eggs. I have had the opportunity here of observing a specimen of urine which contained sulphuretted hydrogen for * Sctmidt's Jahrbiicher, 1863, 13, p. 378. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF TTBINE. 143 a long time, and which was passed periodically by a man whose lower extremities were paralyzed by gout ; the urine, when it con- tained sulphuretted hydrogen, was feebly acid, of bright yellow color, usually deposited a sediment, and immediately blackened very intensely a lead paper held over it. Betz assumes that under certain circumstances sulphide of ammonium from the intestine may get into the blood and then cause symptoms of poisoning, which are similar to those caused by the inhalation of sewer gas. Betz calls the sickness thus caused hydrothion-ammonsemia ; in the cases described by him the freshly passed urine gave for a long time the reactions of ammonia and sulphuretted hydrogen.* It has been intimated above, under the head of Sulphuric Acid (§ 15, B, 3), that sulphates in contact with organic matters at a moderately elevated temperature may easily give rise to the formation of sulphuretted hydrogen, which is one source of this body in the urine. But sulphuretted hydrogen may be generated also without the presence of sulphates, by the simple putrefaction of animal matters containing sulphur, and thus it may happen that sulphuretted hydrogen can frequently be re- cognized by its odor in a urine which contains albumen after standing a short time, as I have had frequent opportunity of observing. E. Sertoli,t moreover, gives an account of a body preeipita- ble by sugar of lead, soluble in ammonia, alcohol, and ether, decomposing with the evolution of sulphuretted hydrogen on beiog heated with dilute acids to 100° C, and which was found by him in the urine of horses, dogs, and human beings. It is easy to become assured of the presence of a body in the urine which contains sulphur, since the urine of men, horses, and dogs develops, on being treated with zinc and hydrochloric acid, sulphuretted hydrogen, which can be detected by the blackening of a strip of paper moistened with sugar of lead so- lution. For the quantitative estimation of the sulphur in the urine, which is not present in the form of sulphates, but in the form of this body which furnishes sulphuretted hydro- gen, the following method may be adopted : The uric acid is * Betz Memorabilien, 1864, p. 146. t Ball' Istituto fisiolog. di Pavia, 1869. Digitized by Microsoft® 144 ANALYSIS OF TEE UBINE. precipitated from the urine of healthy persons and the fil- trate divided into two equal parts. In one half the sulphuric acid is directly estimated, in the other after it has been heated ■with hydrochloric acid and chlorate of potassium till chlorine is developed. From the difference in the amounts of sulphuric acid of the two estimations the amount of sulphur which was originally present not as sulphate is obtained. A twenty-four hours' amount of urine which was 1,500 cc. gave 0-156 gram of sulphuric acid as the product of oxidation of the sulphur con- tained in the sulphur compound. ("W. Lobisch.)* Finally it is to be remarked that Schmiedebergt and MeissnerJ have de- tected hyposulphurous acid as an almost constant constituent of the urine of cats and a very frequent constituent of the urine of dogs. § 35. All Formula : €4H6]Sr403 [OsHeN.Oe] " ANTOISr. ' Carbon Hydrogen Nitrogen . Oxygen 30-38 3-80 35-44 30-38 100-00 A. Presence. AUantoin is found in the allantois fluid of the cow and in the urine of young calves a-s long as they are suckled or fed with milk. It is further found in the amniotic fluid, and in the urine of newborn children within the first eight days after birth. Stadeler found it in the urine of the dog when there was disturbance of the respiration ; Meissner and Joly also found it in dogs, together with succinate of sodium, after a continuous diet abounding in fat ; Kohler found it in the urine of the rabbit after the injection of oil into the lung. Sehottin found it finally in human urine after large amounts of tannic acid had been taken. AUantoin is formed from uric acid by treating it with lead peroxide, ferrocyanide of potassium, or permanganate of potassium. B. Preparation. Uric acid is mixed to a thin paste with * Sitzungsbericht d. wien. Acad., Band 63, II. t ArcMv d. Heilk. 1867, p. 433. % Zeitschrift flir rat. Med. 1868, Band 31, p. 333. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 145 water, heated to boiling, and lead peroxide is added in small portions until the brown color of the latter no longer disap- pears. AUantoin separates from the filtrate on cooling in beau- tiful crystals, while urea remains dissolved in the mother liquor. 0. Microscopic Properties. AUantoin appears under the micro- scope in perfectly clear, shining, colorless, prismatic crystals of a rhombic form, which, when obtained from concentrated so- lutions, unite into star-shaped rosettes. (Funte, Taf. V., fig. 4; 2'^ Aufl., Taf. in., fig. 4.) D. Chemical Properties. AUantoin has no taste and does not act on vegetable coloring matters ; it is soluble in 160 parts of cold water, more readily soluble in hot water. Hot alcohol also takes it up, but it separates again for the most part on cooling. It is insoluble in ether. 1. Concentrated alkalies decompose allantoin with absorp- tion of water into oxalic acid and ammonia. 2. Boiling nitric acid splits it up into urea and allantoic acid. 3. If nitrate of silver and ammonia are added to a saturated solution of allantoin, allantoin silver oxide precipitates in white flakes which, when examined microscopically, are seen to con- sist of clear perfectly spherical globes. The dry compound contains 40 "75 per cent, of silver. 4. Corrosive sublimate does not precipitate a solution of al- lantoin, but it is precipitated like urea by a solution of mercuric nitrate. 5. Allantoin in contact with yeast at a temperature of 30° C. is decomposed into urea and oxalate and carbonate of ammonium. At the same time a new syrupy acid is formed, which is, perr haps, identical with one which I observed together with allan- toin and urea after treating uric acid with permanganate of potassium. E. Detection. To find allantoin the urine is precipitated with basic acetate of lead, filtered, and the excess of lead removed from the filtrate by sulphuretted hydrogen. The filtered so- lution is evaporated to dryness on the water bath, and the residue extracted with boUing dilute alcohol. After the cool- ing of the filtrate, concentrated by evaporation if necessary, if allantoin is present, crystals shoot forth which, after recrystal- lization from hot water, are to be further examined. Besides 10 Digitized by Microsoft® 146 ANALYSIS OF TEE URINE. the microscopic forms of pure allantoin, allantoin silver oxide (D, 3) is e'specially characterized under the microscope by its peculiar globular form. According to Meissner the following method is to be pursued : The urine is precipitated with baryta water, the excess of baryta is carefully removed with sulphuric acid avoiding an excess of the latter, and the alkaline filtrate treated with concentrated corrosive sublimate solution as long as a precipitate results. The mixture, which has now become acid, is neutralized with potassic hydrate, aud further treated with corrosive sublimate solution. The collected precipitates are suspended in water and decomposed by sulphuretted hydro- gen. Allantoin separates from the concentrated filtrate in crys- tals. The allantoin which is obtained is best crystallized once more from hot water, before the microscopic examination and production of the characteristic silver compound. The urine of young calves is evaporated to a syrup on the water bath and placed at rest for several days. The separated crystals are washed and then heated to boiling with a little water. The solution is decolorized by animal charcoal, filtered -while hot, treated with a few drops of hydrochloric acid to pre- vent the separation of phosphate of magnesium, and allowed to «ool, when allantoin will separate in thin bundles of coalescing crystals. The urine of calves, unlike that of full-grown creatures which no longer live on milk, is strongly acid ; it contains as much urea and uric acid as human urine, but no hippuric acid, while, on the other hand, cow's urine, which abounds in hippuric acid, contains no allantoin. APPENDIX. AUoxan. This interesting product of oxidation of uric acid (§ 6, D, 6 and 7) has thus far been found only once by Liebig* in a catarrhal intestinal mucus, and again probably by G. Langt in the urine of a patient with heart disease. *Annaleii d. Chem. u. Phamiacie, Band 121, p. 80. t Centralblatt f. med. Wissenschaft., 1867, p. 63. Zeitschrift f. analyt. Chem., Band 6, p. 394. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF UBINE. I47 36. Leucin. Formula: €„H,3Naj [0„H,3N0,] f Carbon 54-96 Hydrogen 9-93 Nitrogen 10-68 Oxygen 24-44 100-00 A. Presence. Leucin was first obtained as a product of the decomposition of animal matters abounding in nitrogen as well by their putrefaction as by the action of strong acids and alkalies upon them, but very recently it has been recognized as a normal and pathological constituent of various organs and fluids of men and animals, in which it often occurs jointly with tyrosin. According to the recentinvestigations of Kadziejewsky * leucin occurs normally in the pancreas, in the spleen, the lymph glands, salivary glands, in the thyroid and thymus glands and in the liver ; in the kidneys it is doubtful. It does not occur in the testicles, lungs, heart and other muscles, in the brain, blood, urine, saliva or bile. Leucin occurs pathologically in the urine in several diseases, typhoid fever, small-pox, hepatic diseases, and is especially abundant together with tyrosin in acute atro- phy of the liver. V. Gorup-Besanez found leucin with asparagin in the juice of the embryo of the common vetch ( Vicia sativa). B. Microscopic Properties. Impure leucin, as it is first obtained by separation from animal fluids, crystallizes in granular masses, which appear as round spheres, mostly yellow, in part concen- trically striped, here and there also covered with fine points, yet under the microscope showing no definite crystalline form, but frequently rather reminding one of spherical fat-cells. In the pure state it crystallizes in rosettes of leaflets or scales, whose contour is often difficult to distinguish. More frequently the edges are seen as sharp dark lines, so that at the first sight several crystals appear only as needles fine as hairs which terminate in two points. (Funke, Taf. IIL, fig. 6; 2'° Aufl., Taf. IV., fig. 2.) 0. Chemical Properties. — 1. Pure leucin forms white crystalline *Arcliiv f. patholog. Anat., Band 36, p. 1, aucli Zeitschrift f. analyt. Chem., Band 5, p. 466. Digitized by Microsoft® 148 ANALYSIS OF THE URINE. scales, has a greasy feel, and has neither taste nor odor. Water moistens it with difficulty, but dissolves it with tolerable readi- ness ; in alcohol it is more difficultly soluble ; it is not at all soluble in ether. Acids and alkalies take it up with ease. 2. Cautiously heated in a glass tube, open at both ends, to about 170° C, leucin sublimes without previously melting in woolly flocculent masses, which fly about in the air like oxide of zinc partially borne along by the current of air. This inter- esting sublimation is very characteristic of leucin. On being strongly heated, 180° C, it melts and is decomposed into car- bonic acid and amylamin. 3. If a boiling mixture of leucin and sugar of lead solution is carefully treated with ammonia, leucin lead oxide separates in beautiful iridescent leaflets. 4 A solution of mercuric nitrate does not precipitate a solu- tion of absolutely pure leucin. If a precipitate is thus produced, it indicates, especially if the supernatant fluid is colored reddish or rose red, an admixture with tyrosin. 5. Leucin in contact with putrefying animal matters or on being fused with potassic hydrate decomposes, with the forma- tion of carbonic acid, ammonia and hydrogen, into baldrianic acid. I 6. If pure leucin is carefully evaporated with nitric acid on platinum foil, a colorless, scarcely perceptible residue remains. If a few drops of sodic hydrate are added to this residue and heated, the leucin thus treated dissolves according to its purity to a perfectly colorless or more or less colored fluid. If this is carefully concentrated on the platinum foil over the lamp, in a short time it collects into an oily drop, which does not wet the platinum foil but rolls about without adhering to it. This appearance is very characteristic even for leucin not wholly, pure. (Scherer.) 7. Leucin in alkaline solution is decomposed by permanga- nate of potassium into ammonia, carbonic acid, oxalic acid, and baldrianic acid. 8. If leucin is heated in a test tube with manganese dioxide and dilute sulphuric acid, the characteristic odor of valeronitrile is developed ; and if the oxidation is carried farther, especially if concentrated sulphuric acid is used, that of valerianic acid. D. Preparation and Detection. (See under Tyrosin.) Digitized by Microsoft® , ABNORMAL CONSTITUENTS OF URINE. 149 § 37. TiEosm. Formula : esHiiNOs Carbon 59-67 Hydrogen 6-08 Nitrogen 7-73 Oxygen 26-53 100-00 A. Presence. Tyrosin is formed in just tlie same manner as leucin, only a little later, but for the most part together with it during the decomposition of animal matters abounding in nitrogen. Tyrosin never occurs normally in the organism, according to the thorough investigations of Kadziejewsky,* but it does occur in the liver, in the blood of the hepatic and portal veins in diseases of the liver, in the bile of typhoid-fever patients, in the expectoration in croupous bronchial affections, etc. Leyden found it in the expectoration of a girl who had suffered ten years from a cough. It has been found in the urine in typhoid fever and small-pox, and in large quantity together with leucin in acute atrophy of the liver. (Frerichs, O. Schultzen, and L. Eiess.) B. Microscopic Properties. Tyrosin forms a cohesive, snow- white mass which has a silky lustre and consists of long shining needles lying together, which again are themselves formed of very fine needles arranged in star-shaped groups. It crystal- lizes from an ammoniacal solution often in globules, which con- sist of a number of fine needles radiating from the centre, and appear toothed on the entire periphery by the projection of small pointed crystals over the edge of the sphere. Such a tyrosin sphere on being crushed under the covering-glass crum- bles into fragments which consist of very fine white needles. (Scherer.) (Funke, 2'= Aufl., Taf. IV., fig. 3.) 0. Chemical Properties. Tyrosin is without taste and odor, very difficultly soluble in cold water, easily in hot, still more easily in acids and alkalies, but insoluble in alcohol and ether. *Loc. cit. Digitized by Microsoft® 150 ANALYSIS OF TEB UBINE. 1. It evolres ttie odor of phenol and nitrobenzol on being heated. (Kiiline.) It is not capable of sublimation. 2. Nitric acid evaporated carefully witb tyrosin yields besides oxalic acid a yellow body -which is the nitrate of nitrotyrosin; this residue becomes colored a deep red-brown by potassic hydrate and ammonia. If tyrosin is evaporated with nitric acid (sp. gr. 1'2) on platinum foil, the rapidly soluble tyrosia becomes colored bright orange-yellow when first touched by the hot nitric acid. On evaporation it leaves a shining, trans- parent, deep yellow residue, and if a few drops of sodic hydrate are added to it, the fluid immediately becomes colored deep reddish yellow and on evaporation leaves an intense blackish- brown residue. Scherer prefers this reaction even to Piria's (4), because of its easy performance. 3. If a boiling solution of tyrosin is treated with a solution of neutral mercuric nitrate, obtained by treating an excess of mercuric oxide with nitric acid, a yellowish- white voluminous precipitate results. If then a few drops of fuming nitric acid mixed with a large amount of water are added drop by drop to the fluid to be examined, which is allowed to boil anew after the addition of each drop, the whitish precipitate immediately becomes dark red. If the amount of tyrosin is very small, the fluid, which was before only turbid, like milk, becomes pale red, and after a time dark-red flocculi are deposited, while the fluid becomes colorless. (L. Meyer.) 4. If a few drops of concentrated sulphuric acid are poured over tyrosin in a porcelain dish, it dissolves, on being gently heated, with a transitory red color. If then, after diluting with water, the acid is neutralized with a milk of carbonate of barium, boiled to destroy the bicarbonate of barium, and a dilute neutral solution of ferric chloride carefully added to the filtrate, a beautiful violet color is produced. No great amount of leucin should be mixed with the tyrosin. This reaction is very deli- cate ; the color appears bright rose-red in an ordinary test tube at a dilution of 6,000, in a layer two inches thick a distinct rose- red color is observed at a dilution of 25,000, and in one eight inches thick at a dilution of 45,000. (Piria, Stadeler.) D. Preparation. Two pounds of horn shavings are treated with a mixture of five pounds of English sulphuric acid and thirteen pounds of water, and boiled twenty-four hours consec- Digitized by Microsoft® ABNORMAL GONSTITUMNTS OF URINE. 15X Titively, the water evaporated being renewed. The sulphuric acid is then removed by milk of lime, the mixture filtered, washed with hot water, and the filtrate, after the solution has been concentrated to about twelve pounds, is freed from dis- solved lime by the careful addition of oxalic acid. The filtrate is evaporated until a crystalline pellicle forms. The rosettes of crystals obtained consist of leucin with varying amounts of tyrosin, which is seldom absent. The different solubility of the two substances in water is utilized to separate them ; for this purpose they are dissolved in so much boiling water that on cooling only a small part of the crystals separate, which consist of white needles of the difficultly soluble tyrosin. Leucin is obtained from the mother liquor after previous decolorization with animal charcoal and further evaporation in white masses of crystals.* The following method of W. Kiihne t is an excellent one : The pancreas of a well-nourished animal which has been abun- dantly fed five or six hours before death, is weighed while fresh, cut into pieces, triturated with water and sand to a fine mush, ten times its amount of raw blood fibrine is added, and the whole treated with twelve or fifteen parts of water, which should be previously warmed with the fibrine to 45' C. The mass is kept at this temperature with frequent stirring for four or five hours, then a little acetic acid is added, and it is heated to boiling. It is then strained through linen, the fluid is evapo- rated to a thin syrupy consistency, and while still hot is treated with strong alcohol and shaken in a flask until a distinct floccu- lent precipitate results. After cooling, this is filtered, and the filtrate is concentrated by evaporation until it forms a thick pulp when hot. After the mass has stood a day in the cold, it is freed as much as possible from the mother liquor on a filter, washed with a little cold water and then suspended in con- siderable water at about 50° C, when all of the leucin is dis- solved while the tyrosin remains behind nearly white. It is first recrystallized from hot water to purify it, and then from hydrochloric acid or ammonia to obtain large crystals. * Schwanert uber Leucin ; Dissertation, GSttingen, 1857. Stadeler. Anna!, der Chemie und Pharm., Band 116, p. 61. fArcMv f. patt. Anat., Band 39, p. 130. Zeitschrift f. analyt. Oiemie, Band 6, p. 382. Digitized by Microsoft® 152 ANALYSIS OF THE URINE. E. Detection. In acute atrophy of tlie liver under certain cir- cumstances only traces of those substances occurring normally as the final product of metamorphosis, especially urea, are found, while leucin and tyrosin occur as the principal constitu- ents. Such a urine often deposits a greenish-yellow sediment spontaneously, consisting of spherical rosettes of tyrosin nee- dles, and leaves a residue of numerous crystals of both sub- stances when it is evaporated on an object glass. To obtain larger amounts of both bodies Frerichs freed such a urine from the coloring and extractive matters, as it also gave distinct reactions for biliary pigments, by precipitating it with basic acetate of lead, immediately after obtaining it, with a catheter ; he then filtered, precipitated the excess of lead from the fil- trate by sulphuretted hydrogen, and concentrated the clear fluid. After twenty-four hours a sufficiently large amount of tyrosin had separated to suffice for several elementary analyses.* The tyrosin obtained is recrystallized from hot water and the chemical and microscopic tests are applied to it. To find leucin the evaporated residue is next treated with cold absolute alco- hol, as long as it takes up anything, and it is then extracted with boiling alcohol of ordinary strength, when a substance re- mains behind for the most part viscid, dark brown, soluble in water, and containing the remainder of the tyrosin. The alco- holic solution last obtained is evaporated and the syrupy resi- due allowed to stand a long time, when any leucin present separates in the globular form described above, § 36, B, and is to be subjected to microscopic and chemical examination. It is better, having first as much as possible freed the leucin ob- tained from its mother liquor by pressing between paper, to further purify it ; for which purpose its compound with lead oxide may be utilized. The aqueous solution of the leucin, which has been purified as much as possible by pressure, is made strongly alkaline with ammonia for this purpose and then precipitated with acetate or basic acetate of lead solution as long as a precipitate results. The precipitated leucin lead oxide is collected on a filter, washed a little, then suspended in water and decomposed with sulphuretted hydrogen. The fil- * Together with tyrosin still another body crystallizing in a similar form ■was found, which contained more nitrogen (8 '83 percent.). Frerichs, Deutsche Klinik, 1855, Nr. 31, p. 343. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF URINE. 153 trate after evaporation will separate the leucin in pure crystal- line form. (Lehmann.) If the urine should contain albumen, it is first coagulated by heat, and the filtrate used for testing for leucin and tyrosin. It is to be remarked further that such a urine is to examined while fresh, since leucin in contact with decomposing animal matters is very readily decomposed with the formation of bal- drianic acid. The urine from the case of acute atrophy of the liver, described by Frerichs, contained 4-9 per cent, of solid residue and 0-14 per cent, of ash. The residue was strongly acid, and urea was sought for in it in vain. He obtained, besides leucin and tyro- sin, a viscid substance, similar to that which is formed with leucin and tyrosin by the artificial decomposition of protein substances by acids. The ash consisted chiefly of chlorine com- pounds and sulphates ; it was remarkable that the alkaline and earthy phosphates were wholly wanting. These statements were partially confirmed by O. Schultzen and L. Eiess.* § 38. OXYMANDEL AciD. , n TT n r Carbon L^.eJlMJ. j^ Q^^^^^ 38.10 -ni 1 n-vr f\ f Carbon 5'J'"14 Formula : G^KJ^i J tt j a na rn WOT 1 Hydrogen 4-76 100-00 Presence. Oxymandel acid was found by O. Schultzen and L. Eriess t in the urine in several cases of acute atrophy of the liver, together with leucin, tyrosin and paralactic acid. The urine, moreover, contained biliary pigments, biliary acids, small amounts of albumen, and that peptone-like substance which often occurs in the urine after phosphorus poisoning in con- siderable amount (page 100). The urea was either wholly want- ing or was reduced to a minimum. Leucin and tyrosin were never absent, so that these bodies may be regarded as almost as pathognomonic of acute atrophy of the liver, as albumen is of nephritis and sugar of diabetes mellitus. * Loc. cit. f Ueber acut. Phosphorvergiftung und Leberatrophie, Berlin, 1869, p. 69. Digitized by Microsoft® 154 ANALYSIS OF THE URINE. B. Detection and Properties. The urine was freed from its tyro- sin and leucin by evaporation, the mother liquor was precipi- tated with absolute alcohol, the alcoholic solution evaporated, and the syrupy residue after the addition of dilute sulphuric acid completely exhausted with ether. The united ethereal ex- tracts on evaporation left a brown, thin, fluid residue, from which long, thin colorless needles, together with brown oily drops, separated. On treating with water the latter dissolved. Sugar of lead solution caused only a slight flocculent precipitate in the slightly yellow fluid, by which means it was decolorized. Basic acetate of lead gave with the clear, watery filtrate an abundant flocculent precipitate, which, after standing a short time, condensed to a heavy, granular, crystalline powder. The compound was suspended in water and decomposed with sul- phuretted hydrogen. The filtrate yielded, after evaporation, colorless, very flexible silky needles of the new acid. In a pure state oxymandel acid melts at 162° 0. ; it contains water of crystallization which escapes when exposed to the air at 130°. It is quite soluble in warm water, less so in cold water, and readily soluble in alcohol and ether. On heating in a glass tube with calcic hydrate brown oily drops appeared which had the odor of phenol, and in an aqueous solution gave a dark violet color with ferric chloride. The simultaneous occurrence of tyrosin and of oxyman(^l acid in the urine, from the chemical relationship of the two sub- stances, allows us to suppose that the latter springs from the former. This change may be expressed in the following for- mula: GgHnNOa + a3=GO,+NH3 +G„HA [C,8H„NO„ + 0„-OA + NH3 + C„HA]. By a similar method 0. Schultzen and Biess* obtained from the ethereal extract of urine in acute phosphorus poisoning warty groups of delicate, colorless, rhombic leaflets of a new aromatic acid. On fusing with potassium it yielded cyanogen, and on distillation with lime anilin. It melted constantly at 184° to 185° C. ; the silver salt contained 33'92 per cent, of silver. Unfortunately the material did not suffice for an accurate in- vestigation. * Loo, cit. , p. 37. Digitized by Microsoft® ABNORMAL CONSTITUENTS OF UBINE. igg § 39. Brenzcatechin. (Oxyphenic Acid.) W. Ebstein and J. MiiUer* found a substance in the urine of a boy four months old, which corresponded with brenzcateehin in all of its properties. The urine, colorless when passed, re- tained its original color, but if in contact with air, it became first reddish, then gradually darker up to the color of burgundy. On the addition of potassic hydrate the urine became brownish, but later blackish brown, especially on shaking. Detection. Two hundred cc. of the urine in question were evaporated on the water bath, and the residue repeatedly shaken with absolute alcohol. The residue did not become brown as mentioned above; the substance in question had, therefore, been removed by the alcohol completely. The alco- holic filtrate was once more evaporated on the water bath, and the residue repeatedly shaken with ether. After evaporating the ether there remainded a yellow syrupy mass, which was treated with small amounts of water in the cold to separate the hippuric acid. This solution gave all of the reactions of brenz- cateehin. 1. Evaporated over sulphuric acid on an object glass, white, rectangular, prismatic crystals separated. 2. Alkalies produced a green color in the solution. This became gradually greenish brown, brown, and at last almost black. 3. Silver, gold, and platinum solutions were reduced even in the cold. 4. An alkaline solution of copper was reduced on heating. 5. A solution of ferric chloride immediately produced a color which was first dark green, then black. If, further, tartaric acid was added to a fluid which contained only traces of ferric chlo- ride, the mixture rendered ammoniacal, and then treated with some of the aqueous solution of the body in question, the char- acteristic violet color was produced, which changed on the ad- dition of acetic acid to a faint green, becoming violet again after the addition of ammonia. * Viroliow's Axchiv, Band 63, p. 554. Digitized by Microsoft® Igg ANALTSia OF TEE UBINE. 6. Acetate of lead gave a white precipitate soluble in acetic acid. Althougli, on account of dearth of material, the sublimation test and the elementary analysis could not be performed, yet the reactions given correspond so completely with those of brenzcatechin, that scarcely any doubt exists as to the presence of this remarkable substance in the urine in question. In many respects also the urine corresponded with that in which Bodecker found alkapton (p. 114), which was possibly brenzca- techin also. Finally it must be mentioned that V. Gorup-Besanez found brenzcatechin in the leaves of the wild vine (AmjoebpsisJwd^ racea), and Hoppe-Seyler recognized it as a product of the de- composition of starch, cane sugar, sugar of milk, and cellulose, after heating these substances from four to six hours with water in sealed tubes to from 200° to 280° 0. § 40. UbOEUBROH^MATIN AOT) IlEOPUSCOHaiMATIN. These two well-characterized pathological coloring matters, which appear to stand in close connection to hsematin, were found by F. Baumstark* in the urine of a patient suffering with leprosy. The color of the urine was at first a deep dark red) like Bordeaux wine, and gradually became brown red and toward death a pure dark brown, almost black. Preparation. The urine was subjected to dialysis, when a yellow-colored fluid like normal urine passed through the membrane with the salts, while a brown slimy substance re- mained behind. This readily dissolved in sodic hydrate from which the addition of an acid precipitated the urofuscohsema- tin, while a beautiful magenta-red coloring matter, urorubrohse- matin, remained in solution. The latter separated when the red solution was subjected to dialysis. The quantity of the two pigments amounted in twelve days to about two grams. Urorubrohcematin {GesH-sJ^^ii^^s) was obtained as a bluish- black light mass, which is insoluble in water, alcohol, ether, and chloroform ; but is soluble in the fixed alkalies, their car- bonates and phosphates, and also in alcohol containing acid. * Berliner Bericlite, Band 7, p. 1170. Pfliiger's ArcMv, Band 9, p. 568. Digitized by Microsoft® ABNOBMAL CONSTITUENTS OF UBINE. 157 None of these solutions are dichroic, even after the addition of a zinc salt. The acid solution shows a narrow absorption band in front of D and a broad one behind D, so that it appears as if the oxyhsemoglobin spectrum were displaced toward the left, yet the bands stand nearer each other than in the oxyhsemoglobin spectrum. On dilution the narrow band disappears first. The alkaline solution shows a band on the right of D, one at E, a broad one right of F, and one to the right of G, without the blue being absorbed between the two last ; all four bands di- minish uniformly on dilution. Urofuscolicematin (GesHiceNjOje) is a black, pitchy, shining mass with a similar behavior with solvents as the red coloring matter. The solutions are not dichroic. In the spectrum a shadow appears between D and E, and a second one in front of F, which can only be recognized with difficulty. In both coloring matters the proportion of carbon to nitrogen is as 8 to 68, as in hsematin ; both yield on dry distillation a distillate, which like the hsematin derivatives investigated by Hoppe-Seyler show the pyrrol reactions very beautifully. Hsemin crystals cannot be produced from the coloring matters. § 41. Acetone, Alcohol, and Ethyldiacetic Acid. F. Eupstein* found acetone and alcohol in the urine of a woman forty years old suffering from severe diabetes. The breath of this woman had an odor of chloroform, which was not noticed in the freshly passed urine, but which became very striking after a few hours. Detection. During six weeks the urine which was passed was daily subjected to distillation, and the distillate after the addi- tion of sulphuric acid was repeatedly subjected to fractional distillation. The product obtained on the fourth distillation had a repugnant urinous odor only slightly resembling that of acetone, but it was inflammable, did not mix with sodic hydrate, by which it was blackened just as by sulphuric acid, and gave a crystalline precipitate with a drop of a concentrated solution of acid sodium sulphite (characteristic reaction for aldehyd and acetone). The first fraction of this fluid distilled at 67° * Centralblatt f. d. med. Wissenschaft, 1874, Nr. 55. Digitized by Microsoft® 158 ANALYSIS OF THE URINE. C. The distillate was treated witli fused chloride of caleiuni, then distilled on the water bath, and the distillate once more subjected to similar treatment. That which now volatilized at 60° 0. (40 cc), which had an odor of acetone, was once more distilled in small portions over the water bath, and the portion which passed over at 58° C. was employed for the elementary analysis. Further heating of the chloride of calcium residue over a free flame yielded a fluid consisting essentially of ethyl alcohol. The alcohol was converted into acetic ether, and this after re- peated rectification submitted to analysis. Derivation of Acetone and Alcohol. Gerhardt first laid stress on the fact that a diabetic urine in which acetone is contained or is formed is at the same time characterized by a remarkable reaction, namely, treated with ferric chloride, a deep red-brown color is produced. This reaction corresponds with the de- meanor of ethyldiacetic acid discovered by Geuther, which decomposes with great readiness into acetone, alcohol, and car- bonic acid. Since now the freshly passed urine gave the above reaction with ferric chloride, but did not have the odor of acetone, and since the iron reaction disappeared on boiling as well as after long standing, and instead of it the acetone odor appeared, Eupstein supposes that this diabetic urine originally contained ethyldiacetic acid, and that by its decomposition acetone and alcohol were formed. This supposition gains probability from the fact that normal urine treated with ethyldiacetic acid be- haves exactly like the above specimen of diabetic urine. Fi- nally Eupstein succeeded in isolating a body from alarge amount of this diabetic urine after acidulating it with acetic acid and shaking with ether, which after the addition of an ethereal solution of ferric chloride immediately showed a deep brown color. Since now alcohol could be detected at the same time in the urine, Eupstein considers that the presence of ethyldiacetic acid in diabetic urine is proved, and by its decomposition ac- cording to the formula ^eHsNaa^ + 2H,a=€3Hea + €,H«a + ]SraH€a3 (Ethyldiacetic (Acetone) (Alcohol) (Bicaxbo- acid) nate of sodium), Digitized by Microsoft® UBINART SEDIMENTS. 159 acetone and alcohol are first formed with the separation of car- bonic acid. IV. URINABY SEDIMENTS. §42. The various deposits which occur more or less in every urine, and which are in part passed with it and in part are first sepa- rated after a shorter or longer time, are termed urinary sedi- ments. The microscope shows that they consist of organized and non-organized forms, and that the latter are sometimes amorphous and sometimes occur in well-formed crystals. We divide sediments, therefore, into organized and non-organized, and must distinguish the normal which occur in every urine from the pathological sediments. If we leave normal, freshly passed urine a short time at rest in a closed glass, light clouds of mucus are soon observed to sink, which mucus comes from the mucous membrane lining the urinary passages and the blad- der, and in which the microscope shows, besides the different forms of epithelium from the urinary passages, etc., isolated mucous corpuscles. Very frequently, often on very slight dis- turbance of the health, the urine soon after cooling deposits a sediment consisting of fine or coarse molecules, which are easily dissolved again by the application of gentle heat. These consist of a mixture of acid urates, in which, according to the investigations of Bence Jones, urate of potassium, sodium, and ammonium, in feeble combination with an excess of uric acid are never wanting, but with which urate of calcium and mag- nesium may also be admixed. (Plate II., fig. 1.) In perfectly normal urine so small an amount of urates occurs that they remain in solution a long time after cooling ; if, however, the urine is very concentrated, or if an abnormal amount of urates is separated by the kidneys, they are deposited as a sediment very soon after cooling. In most febrile conditions, and under all circumstances in which oxidation in the blood is impeded, the urates appear most frequently as the long-familiar " sedi- mentum lateritium." We mentioned above, in § 1, that urine on standing very frequently underwent an acid fermentation, which after a shorter or longer time was always followed by Digitized by Microsoft® 160 ANALTSIB OF THE URINE. an alkaline one. The urine in the first stage of this decom- position frequently assumes a somewhat darker color, which commences on the surface and gradually and slowly proceeds downward. According to the investigations of Pasteur oxygen is absorbed during this stage, so that this first act of the de- composition of urine must be designated as a process of oxida- tion. In the alkaline fermentation, on the contrary, the color of 'the urine becomes gradually paler. This act of fermentation stands in the nearest relation to the formation and separation of many sediments. If we examine the sediment of urates just spoken of under the microscope, after the acid fermentation of the urine has commenced, we shall find first isolated fermentation spores and in addition mucous coagula in broad or narrow curved bands. (Plate IT., fig. 2.) On increasing acidification the appearance becomes changed. The stronger acids are formed, among which may be especially mentioned acetic acid, which is never wanting in old urine, and decompose the urates ; the latter decrease, but ia their place beautiful rhombic crystals of uric acid appear, which are usually colored yellow, and which are not rarely accom- panied by single crystals of calcic oxalate. (Plate II., fig. 4) The separation of uric acid, however, is not always preceded by a sediment of urates, but very frequently takes place immedi- ately during the stage of acid fermentation in crystals recogniz- able by the naked eye as a granular sand with a golden lustre. According to the investigations of Voit and Hofman* sedi- ments of uric acid may separate without previous fermentation, since the acid phosphate of sodium decomposes the alkaline urates dissolved in the urine with the formation of a basic salt. In fact, if equivalent amounts of the solutions of the two salts are brought together, after a time crystalline uric acid pre- cipitates and the fluid has an alkaline reaction. These facts, according to Voit, completely explain the origin of uric acid sediments. The action of the acid phosphate of sodium on the alkaline urates commences immediately after the forma- tion of acid urine ; the urates and then the uric acid are pre- cipitated more rapidly when the urine contains a large amount of acid phosphate. It is self-evident that this precipitation * Zeitsohrift f . analyt. Chemie, Band 7, p. 397. Digitized by Microsoft® UBINABT SEDIMENTS. 161 may take place even within tlie urinary passages and bladder, and may thus give rise to the formation of gravel or calculi. This change of the two salts is made more rapid either by a more abundant secretion of acid phosphate of sodium or by a greater concentration of the urine. When the action of the acid phosphate of sodium is rapid, the precipitate is amorphous, and when slow the uric acid separates in the crystalline form. Through this transposition the acid reaction of the urine is gradually diminished, so that an alkaline reaction may easily occur even before the decomposition of the urea, if only just enough acid phosphate of sodium is present to form a basic salt with the sodium in combination with uric acid. After a shorter or longer time, often only after some weeks, the second act of the decomposition of urine, alkaline fermenta- tion, commences. The urea is then decomposed into carbonate of ammonium, according to Tieghem, by the action of a small torula, which consists of a chain or heap of small spheres with- out an integument, of about 0"0015 millimeter in diameter, and without nuclei. This vegetable ferment appears to increase by budding, and never develops on the surface of the fluid, but either in its interior or at the bottom of the vessel, where it finally forms a white deposit mixed with the separated salta As soon as this torula occurs in the urine the decomposition of the urea commences. If infusoria appear at the same time, as is usual, the urea is decomposed more slowly, but if other vegetable productions appear on the surface, by which the de- velopment of the torula is hindered, the urine may remain acid for months, according to Tieghem.* If the alkaline fermenta- tion has commenced, and if the urine has still only a feebly acid or neutral reaction, the sediment has another appearance. The crystals of uric acid gradually dissolve and their rudiments are frequently beset with prismatic crystals of urate of sodium, and here and there with dark spheres of urate of ammonium. When the reaction finally becomes alkaline, uric acid has dis- appeared, shining crystals of ammonio-magnesian phosphate, and dark, often prickly spheres of urate of ammonium, appear in the sediment, besides a very large amount of amorphous * Concerning the decomposition of urine see also Hallier, " Gahrungserscltein- ungen, etc., etc.," Leipzig, bei W. Engelmann, 1867, and § 53, "Spores and Infusoria." 11 Digitized by Microsoft® 163 ANALYSIS OF THE UBINE. phosphate of calcium, while the surface of the urine is often thickly covered with mould. (Plate II., fig. 5.) Under pathological conditions both stages of urinary fermen- tation may occur in the bladder. If the acid fermentation occurs, uric acid will be separated and will be passed with the urine in the form of coarse or. fine gravel. In the alkaline fermentation the sediments mentioned are frequently mingled with large amounts of pus. (Plate II., fig. 3.) We must not leave the fact unmentioned here, that by the use of foul cathe- ters, elastic as well as silver, germs of spores, etc., have been introduced into the bladder, and thus given rise to the alkaline fermentation within the bladder with all of its evil consequences. {Niemeyer and Teuflfel, Traube and Fisher.) Frequently under pathological conditions large amounts of calcic oxalate occur in th« sediment ; on the other hand, sedi- ments of cystin, tyrosin, xanthin, sulphate of calcium,* and crystallized phosphate of calcium are rare. Of the organized substances, in addition to the different forms of epithelium, blood and pus corpuscles, renal casts, spermatozoa, and sarcinse are frequent found pathologically, and under certain circum- .stances, masses of cancer and tubercle. We will now consider the individual constituents. 1. Non-Oeganized Sediments. § 43. Uric Acid. Uric acid occurs as a sediment only in strongly acid urine, and is frequently accompanied by one of the urates. As a sediment it is never colorless, though at times it is pale yellow, but is usually of a deep-yellow, orange-red, or brown color. Its crystalline character is readily recognized even with the un- aided eye, and if we examine it under the microscope, it ap- pears in the forms mentioned above under uric acid, § 6. Four-sided tables or six-sided prisms of rhombic shape, from which often by the rounding of the obtuse angle spindle or barrel-shaped crystals are formed, are characteristic. If, how- ever, there is any doubt about any crystal, it is only necessary * Valentiner, med. Centralblatt, 1863, p. 913. Digitized by Microsoft® URTNABY SEDIMENTS. 163 to dissolve the sediment on an object glass in a drop of potassic hydrate, and to add a little hydrochloric acid, when the usual forms will soon appear. It is separated from the urates mixed with it by heating and filtering; the urates are in solution, whUe free uric acid will remain behind on the filter. Finally it can be tested chemically, especially by the murexid test, for which very minute quantities of uric acid will suffice. (Plate I., figs. 2 and 3 ; Plate n., fig. 4; Plate III., fig. 1.) § 44. Urates. If urates are present in the sediment together with free uric acid, they may be separated by heating, as has been indicated, and after the filtrate has become cool, they separate. The color is very variable grayish white, white, rose red, brown red, or purple red ; they often look very much like organized bodies, as blood, pus, etc., and can be distinguished from them only by the microscope ; they are, however, readily recognized chemi- cally by their behavior with nitric acid and ammonia (formation of murexid) as well as by their solubility on heating. Sediments of urates occur most frequently in febrile condi- tions, and under all circumstances in which the respiration, or rather oxidation in the blood, is interfered with. Bence Jones has examined the sediments consisting of urates very carefully, and has found that they contain in 100 parts 91 '06 to 94"36 per cent, of iiric acid, 3"15 to 5 per cent, of potas- sium, 1*11 to 1'87 per cent, of sodium, and 1"36 to 3'36 per cent, of ammonium. If these precipitates are washed with water on the filter, they frequently show crystals of uric acid under the microscope, and on boiling with water they leave uric acid be- hind undissolved. From these experiments it is evident that the sediment of amorphous urates often contains far more uric acid than is requisite to form acid salts, and that this excess is held in such feeble combination by the acid salts that cold water sets free crystals of uric acid. Bence Jones succeeded in producing artificially a urate of potassium of similar be- havior, which was found, on analysis, to be a fourfold acid salt. It follows from this that the sediment of amorphous urates has no constant composition. It is a mixture of different acid urates, which are modified in their crystalline form by other Digitized by Microsoft® 164 ANALYSIS OF THE UBINE. ' substances in the urine. The potassium salt was found for the most part in greater amount than the urate of ammonium or sodium ; there is also usually an excess of uric acid in combina- tion with these acid salts, so that by washing with water readily decomposable quadruple urates are formed, by which the sedi- ment is made more susceptible of variation in its composition. 1. AcMj Urate of Sodium in most cases appears in the form of amorphous, irregular granules of very small size. Produced artificially by dissolving uric acid in a warm solution of ordinary phosphate of sodium, it is obtained in microscopic prismatic crystals which ordinarily unite to form masses grouped in a stel- late form. It is found at times in the urine in a similar form after acid fermentation is complete and when alkaline fermentation is just commencing. Microscopic examination of the sediment in this transition stage often shows very complicated forms. The crystals of uric acid separated during acid fermentation and now more or less dissolved are covered with beautiful groups of prismatic crystals of urate of sodium, while at the same time concentrically striped spheres are observed which here and there adhere to the prismatic crystals and probably consist of urate of ammonium. Such a urine still feebly reddens lit- mus as fermentation progresses, and when a neutral reaction has already resulted, groups of prismatic acid urate of sodium crystals are sometimes seen, but now accompanied by beautiful large crystals of ammonio-magnesian phosphate. Acid urate of sodium dissolves in water with difficulty ; one part requires 124 parts of boiling water, and 1,150 parts of cold water. On the addition of hydrochloric acid crystals of uric acid are separated. 2. Acid Urate of Potassium is also frequently found in the sediment of urates, and is similar to the sodium salt in every respect. 3. Acid Urate of Ammonium. This sediment occurs chiefly in alkaline urine mixed with the earthy phosphates. Under the microscope it appears in spherical, opaque masses, which are studded with peculiar, fine, prominent points. If a drop of hydrochloric acid is added to it on a glass slide the familiar crystals of uric acid very soon appear. It dissolves in hot water but separates again on cooling. If it is treated with a very little potassio hydrate, ammonia is evolved ; with nitric Digitized by Microsoft® UBmABY SEDIMENTS. 165 acid and ammonia it gives the well-known murexid reaction, like pure uric acid or other urates. (Pl&te II., fig. 5.) 4. Acid Urate of Gakium occurs only rarely and in small quantity. It forms a white amorphous powder, difficultly solu- ble in water, and on ignition leaves a residue of carbonate of calcium. A specimen of the acid urine, in which the more or less col- ored amorphous sediment is suspended, is moderately warmed in a test tube. If complete solution takes place only urates are present, and the microscope with a two hundred to three hundred magnifying power will show the forms represented in Plate n., figs. 1 and 2. If a crystalline residue remains be- hind after heating, it may consist of uric acid with which a few crystals of calcic oxalate are frequently mingled. (Plate II., fig. 4) In order to test more particularly for any bases pres- ent, the sediment is filtered off, washed with dilute alcohol, then dissolved in hot water, treated with hydrochloric acid, the uric acid which separates after twelve hours filtered off, the filtrate evaporated to dryness on the water bath, and the residue tested for potassium, sodium, calcium, magnesium, and ammo- nium, according to the common methods. If the urine has an alkaline reaction, the uric acid in the sediment is present mostly as urate of ammonium, which can be readily recognized under the microscope from its sea-urchin- like spheres. (Plate II., fig. 5.) All the urates, like pure uric acid, give the well-known murexid reaction with nitric acid and ammonia. (§ 6, D, 8.) The distinction of urate of sodium and potassium from the urate of ammonium under the microscope is easy, if the washed sediment is treated with hydrochloric acid and allowed to evap- orate slowly on an object glass. The microscopic examination shows now in addition to the crystals of uric acid, cubes of chloride of sodium and chloride of potassium when the urates of sodium and potassium are present, and the leafy crystals of chloride of ammonium when urate of ammonium is present. § 45. Oxalate of Calcium. A. Presence. Though oxalic acid is very widely distributed throughout the vegetable kingdom, it occurs only in very slight Digitized by Microsoft® 166 ANALYSIS OF THE UBINE. amount in the animal organism, and then always in combina- tion with calcium. In the urine calcic oxalate occurs both normally and pathologically as a sediment in the form of con- spicuous crystals, especially in cases of disturbed respiration, emphysema of the lungs, rachitis, after epileptic convulsions, and during convalescence from severe diseases, especially ty- phoid fever. Calcic oxalate, however, occurs in solution also in urine which does not deposit a sediment, and may remain in solution a long time, since, besides other constituents of the urine, the acid phosphate of sodium especially possesses the power of dissolving calcic oxalate. Calcic oxalate frequently accompanies the sediments of uric acid and urates. (Plate I., fig. 3 ; Plate II., fig. 4.) Vegetable food, sparkling wines and beers, also the internal use of alkaline bicarbonates and salts with the organic acids, and of free uric acid and urates, often increase the amount of cal- cic oxalate in the urine. The statements of Schunk,* according to whom the oxalic acid of the urine takes its origin from the decomposition of the oxalurate of ammonium which is never wanting in normal urine, were not verified by me. In progressing decomposition of the urine oxalurate of ammonium is not, as Schunk believes, decomposed into oxalic acid and urea, but is transformed directly into carbonate of ammonium.t B. Microscopic Properties. Oxalate of calcium, artificially pre- pared by precipitating a calcium salt with oxalate of ammonium, etc., appears under the microscope in perfectly amorphous masses, in which no trace of crystallization can be perceived. If it separates from the urine as a sediment, however, it shows very characteristic forms which are readily recognizable. The crystals of calcic oxalate appear in the form of small, elegant, shining, perfectly transparent, sharp-edged quadrilateral octa- hedra, which are highly refractive, and have a great resem- blance to envelopes, but with these there are also sometimes a few very pointed ones. Beneke describes also peculiar hour- glass shaped crystals, and others which appear like quadrila- teral prisms with pyramidal ends. (Plate I., fig. 3.) * Proceedings of the Royal Society, vol. 16, p. 140. f Zeitschrift f . analyt. Chemie, Band 7, p. 230. Digitized by Microsoft® UBINART SEDIMENTS. 167 Very beautiful calcic oxalate crystals can be easily separated from a urine whicli does not deposit a sediment, if it is covered with a layer of a dilute solution of oxala^te of ammonium with- out stirring : I have artificially prepared in this manner a large number of the most beautiful forms. The behavior of calcic oxalate toward acid phosphate of sodium is interesting. If a solution of ordinary phosphate of sodium is treated with officinal phosphoric acid, until a drop of the mixture is no longer ren- dered turbid by a solution of chloride of barium, a proof that the fluid still contains only acid phosphate of sodium, dilute solutions of chloride of calcium and oxalate of ammonium can be added drop by drop without producing any cloudiness and separation of calcic oxalate. If then very dilute sodic hydrate is carefully added, drop by drop, to this mixture, which even after long standing remains perfectly clear, the calcic oxalate in solution separates after a time in very beautiful regular crys- tals. The acid solution, which is obtained by boiling uric acid with phosphate of sodium, can also hold calcic oxalate in solu- tion, and after evaporation yields in addition to urate of sodium often very beautiful quadrilateral octahedra of calcic oxalate. The crystals are insoluble in water and are scarcely affected by acetic and oxalic acids, but are readily dissolved by the strong mineral acids. C. Detection. Since oxalic acid in the urine always occurs only in combination with calcium, it can very readily be recog- nized in all cases by its characteristic crystalline forms. The peculiar envelope form is especially important, since it ren- ders confusion with other sediments impossible. The only possibility, perhaps, would be in confounding it with chloride of sodium, yet aside from the fact that the latter never occurs as a sediment, it is also sufficiently distinguishable from calcic oxalate by its solubility in water. Moreover, at times larger forms of calcic oxalate occur which have some resemblance to the crystals of ammonio-magnesian phosphate to be described presently, but the solubility of this double salt in acetic acid, in which, as we know, calcic oxalate is insoluble, as well as an accurate microscopic examination, does not allow of a mistake. If, moreover, the urine is very acid, the crystals of calcic ox- alate separate more readily if the free acid is nearly saturated and the urine is allowed to stand at rest for a time ; for we Digitized by Microsoft® 168 ANALTaia OF THE URINE. mentioned above that the crystals were quite soluble in a solu- tion of acid phosphate of sodium. For this purpose the urine is placed in a small conical glass, and when the sediment has collected in the point, the supernatant fluid is poured off and a drop containing the sediment is put on a glass slide. Calcic oxalate in solution may be detected with absolute certainty in the following manner : The urine to be tested (400 to 600 cc.) is treated with a solution of chloride of calcium, su- persaturated with ammonia, and the precipitate which occurs dissolyed in acetic acid, of which an excess is to be carefully avoided. After twenty-four hours the precipitate, in which uric acid is rarely absent, is collected on a small filter, washed with water, and a few drops of hydrochloric acid poured over it. Any calcic oxalate present is dissolved and the liric acid remains be- hind on the filter. The filtrate is diluted in a test tube with 15 cc. of water, and by means of a pipette is very carefully just covered with a sufficient amount of very dilute ammonia. The fluids gradually mix if left at rest, and after twenty-four hours all of the calcic oxalate present will have collected on the bot- tom, and under the microscope will appear in the form of the most beautiful octahedra. I have frequently been able to prove the presence of tolerable amounts of calcic oxalate in solution in the urine by using this method, when no trace of it was to be discovered in the sedi- ment ; but I have also quite frequently tested normal urine for calcic oxalate with a negative result, so that I am still doubtful whether oxalic acid is to be reckoned among the normal or abnormal constituents of human urine. § 46. Eaethy Phosphates. These sediments consist of calcic phosphate and ammonio- magnesian phosphate. It is very rare that only one of these compounds is met with ; in most cases the two occur at the same time. On account of their ready solubility in very dilute acids, they cannot form in a strongly acid urine, but appear always only when the urine is but very feebly acid, neutral, or alkaline, so that the alkaline fermentation has already com- menced either in the bladder or outside of it. 1. Ammonio-Magnesian PJiosphate, Mg]SrH4P©„6H2a [2MgOjE"H4 Digitized by Microsoft® UBINABT SEDIMENTS. 169 0, PO5 + 12H0] . This sediment is not met with in normal urine, but always appears in very beautiful crystals when the urine becomes very feebly acid or alkaline. In some diseases, in severe affections of the bladder and spinal cord, often the whole sediment consists of these crystals. Lehmann found a shining white sediment in a diabetic urine, which consisted only of the ammonio-magnesian phosphate without any traces of calcium. The crystals of this double compound (triple phosphate) are always very easy to recognize from their conspicuous forms. The forms which occur most frequently are combinations of the rhombic vertical prism, which have a great resemblance to the lid of a coffin. (Plate II., fig. 3, fig. 5.) The crystals are insolu- ble in hot water, but acetic acid readily causes them to disap- pear, by which they are distinguished from similar forms of calcic oxalate. They are not attacked by alkalies. 2. Phosphate of Calcium, £2i,2 (PO,) [30aO,PO5] andGaHPO^ [2Ca 0,H0,P05]. This is an amorphous, and frequently also a crys- talline powder. Phosphate of calcium is insoluble in water though soluble in acids, even acetic acid, and is precipitated from these solutions in an amorphous form by alkalies. It oc- curs also only in feebly acid, neutral, or alkaline urine. Frequently, especially in urine with a feebly acid reaction, the phosphate of calcium is only held in solution by carbonic acid, and immediately separates in white flakes, very like a coagulum of albumen, as soon as the carbonic acid is driven off by heat. Not very rarely also sediments of crystallized phosphate of calcium are found which frequently occur alone, but at times mixed with triple phosphate. The size, form, and grouping of the crystals of phosphate of calcium in the sediment varies very considerably, yet they always present sufficiently marked pecu- liarities to be immediately recognized under the microscope. The crystals are sometimes isolated, sometimes collected to- gether; the latter is more frequent, in which case they form clumps and rosettes. Sometimes they are thin and needle- shaped, and then often form spherical rosettes of crystals by crossing each other at right angles and lying together ; at times they are narrow and smooth and have sharp-pointed ends. But very frequently the crystals are thick, and more or less wedge- shaped, and are joined together by their pointed ends, so that Digitized by Microsoft® 170 ANALYSIS OF THE VBINE. they describe more or less complete parts of a circle. The broad free end is usually somewhat oblique, and the more per- fect crystals appear to be formed of six surfaces. Urine which separates crystallized phosphate of calcium in large amount is usually pale, considerable in quantity, and has a feebly acid reaction, but readily becomes alkaline in consequence of an ad- mixture of mucus. Bence Jones says that this sediment may be produced at pleasure by taking lime-water or acetate of calcium. According to him, the crystallized phosphate of cal- cium is €!aHP04 [SOaOjHOjPOjJ, while the amorphous is Ga- 2(P0,) [30aO,PO,]. The two conditions on which the appearance of crystallized phosphate of calcium depends, but which need not exist to- gether, are an excess of phosphate of calcium and a feebly acid reaction of the urine. If, therefore, normal urine is treated with a little chloride of calcium and nearly neutralized with sodic hydrate, it is often possible to obtain numerous crystals perfectly similar to those described. Detection. The recognition of the earthy phosphates pre- sents no difficulties, especially the first-mentioned, since its presence, as well as its microscopic and chemical properties, characterize it sufficiently. If they should occur mixed with other sediments, the following points will serve as distinguish- ing characteristics : Urates dissolve readily on heating the urine, phosphates remain undissolved even at a boiling temper- ature. Calcic oxalate, which in some forms may well be con- founded with the ammonio-magnesian phosphate, is insoluble in acetic acid, whereas the latter is readily taken up. Free uric acid probably never occurs with the earthy phosphates, yet uric acid is readily recognizable both by its crystalline form and its solubility in alkalies. The murexid reaction finally would remove all doubt. The familiar reactions serve to detect calcium, magnesium, and phosphoric acid. A small portion of the acetic acid solu- tion is tested for phosphoric acid with uranium solution. The calcium is precipitated from a second specimen by an excess of oxalate of ammonium, and the phosphate of magnesium is pre- cipitated from the filtrate by ammonia. Digitized by Microsoft® UBINABY SEDIMENTS Yi\ §47. Oystin. Formula : OsHjNSO, [CoH,NS,0,] Carbon 39-75 Hydrogen 5 -78 Nitrogen 11-57 Sulphur 26-45 Oxygen 26-45 100-00 A. Presence. Cystin was first discoyered in a urinary calculus, but later it lias been found tliat, besides in such concretions, cystin often occurs also dissolved in the urine and may be pre- cipitated by acetic acid. It also occurs as a sediment mixed with urate of sodium. The occurrence of cystin as a calculus is rare, for of one hundred and twenty-nine obtained only two contained -cystin. (Taylor.) Eecently Cloetta found cystin in the fluids of the kidney together with inosite and hypoxanthin. Scherer discovered it once in the liver recently. J. Dewar and A. Gamgee state that they found cystin in the sweat in a few cases. Julius Miiller * describes a calculus containing cystin which was removed by operation from the bladder of a boy six and a half years old. This boy's urine, obtained before the operation only in small amount, was alkaline, and deposited a sediment which was free from uric acid and earthy phosphates, and abounded in mucous corpuscles ; there was only a little urate of sodium in solution, but much chloride of sodium. The calcu- lus weighed 268|- grains and contained 55-55 per cent, of cystin. Directly after the operation the urine had an acid reaction, a mucous sediment, and contained less uric acid and earthy phos- phates than normal urine. Eight weeks later, however, the alkaline reaction recurred again, and it contained much chlo- ride of sodium and urea, but only traces of uric acid. On quiet standing it deposited a sediment of ammonio-magnesian phos- phate and cystin, which, after removing the magnesium salt with acetic acid, was easily recognizable under the microscope by its cystalline form. The filtered urine also gave within * Archiv d. Phann., Marz, 1853, p. 338. Digitized by Microsoft® 173 ANALYSIS OF THE UBINE. twenty-four hours after the addition of acetic acid a precipitate soluble in ammonia, on the evaporation of which most excellent microscopic tables of cystin were obtained. From this it fol- lows that the production of cystin in the organism of the boy continued also after the operation. Toel * made interesting observations upon the formation of cystin on two girls in Bremen, by whom this remarkable body was constantly passed with the urine, as the result of a kidney trouble (nephritis calculosa), partly in solution, and partly as a sediment. The amount of cystin secreted amounted on the average to 1"4 grm. in twenty-four hours in each. Another very interesting case, in which cystinuria lasted for years, is described by Bartels.t Not infrequently large concretions of almost chemically pure cystin are passed with urines containing cystin as a sediment. The little stones of yellow color and crystalline structure vary from the size of the head of a pin to that of a pea, and are so characteristic even in their exterior that they cannot readily be confounded with any other urinary concretion. Whoever has once seen them will always recognize them again at the first glance. B. Microscopic Properties. Cystin crystallizes under the mi- croscope in colorless, transparent, six-sided plates or prisms. Since, however, uric acid at times crystallizes also in six-sided tables, we must not rely on microscopic examination alone, but must carefully examine such a sediment chemically also. (Plate III., fig. 4.) C. Chemical Properties. — 1. Cystin is neutral without odor or taste, insoluble in water, yet soluble in mineral acids and oxalic acid, with which it forms saline, easily decomposable com- pounds. Acetic and tartaric acids do not dissolve it. 2. If cystin is heated with nitric acid, it dissolves with de- composition, and on evaporation leaves a reddish-brown mass which does not give the murexid reaction with ammonia. 3. Cystin does not fuse on being heated on platinum foil, but it inflames and burns with a bluish-green flame, while a sharp, acid, characteristic odor, like that of hydrocyanic acid, * Annal. d. Cliem. u. Pharm., Band 96, p. 34 et seg. f Virclaow's Archiv, Band 26, p. 419. Digitized by Microsoft® • URINABT SEDIMENTS. 173 is evolved. On dry distillation it yields ammonia and a stink- ing oil, leaving a residue of porous charcoal. 4. Alkaline hydrates and carbonates, as well as ammonia, dissolve cystin with ease, but carbonate of ammonium does not. It is, therefore, always precipitated from its acid solution by carbonate of ammonium, and from its alkaline solution by acetic acid. 5. If cystin is boiled with potassic hydrate in which oxide of lead has been previously dissolved, a large amount of lead sul- phide separates. (Liebig.) 6. If cystin is boiled with alkaline hydrates, ammonia and a gas which burns with a blue flame are evolved. 7. If a little cystin with a few drops of sodic hydrate are heated to boiling on a silver foil, there results a brown or black spot of sulphide of silver which cannot be washed away. 8. If cystin is dissolved by heating with potassic hydrate, diluted and treated with a solution of nitroprussiate of potas- sium, the well-known, beautiful, violet sulphur reaction occurs with great magnificence. (J. MiiUer.) This reaction is particu- larly beautiful. D. Detection. Cystin is characterized especially by its crys- talline form, its solubility in the mineral acids and alkalies, and by its behavior with nitric acid and with heat. Liebig has given besides for its recognition the reaction with caustic pot- ash and lead oxide, which produce when boiled with cystin a very abundant precipitate of sulphide of lead. But in employ- ing this reaction we must bear in mind that other bodies con- taining sulphur, such as albumen, fibrine, etc., exhibit a like behavior, so that we must first be convinced of the absence of these substances, and remove them if present. Cystin is easily separated from the earthy phosphates and the urates by boiling and treating with acetic acid, since it is soluble neither in boiling water nor in acetic acid, while the latter are readily dissolved thereby. Uric acid which, as has been mentioned, at times also crystallizes in six-sided tables, is sufficiently characterized by its murexid reaction, since cystin treated in the same way leaves only a reddish-brown residue. Digitized by Microsoft® 174 ANALYSIS OF TEE URINE §48. Tyeosin. (COMPAKE §37.) Stadeler and Frerichs observed in the urine of a woman suf- fering from acute atrophy of the liver, after standing awhile, a sediment of greenish-yellow spherical crystals, which consider- ably increased after slight evaporation of the urine. It was extracted with dilute ammonia, and the first crystals which formed from the solution were recognized as tyrosin. Another more soluble body, probably homologous with tyrosin, whose quantity of nitrogen amounted, not as in tyrosin to 7"73 per cent., but to 8'83 per cent., remained in the mother liquor. O. Schultzen and L. Riess* found the same sediment in acute atrophy of the liver. The clear urine, removed from the bladder with the catheter, on cooling deposited delicate almost colorless needles aggregated into sheaf-like bundles, which were recog- nized by all of the reactions as tyrosin. §49. Xanthin (Hypoxanthin?). (COMPAEB § 5. ) Bence Jones t found in the urine of a boy nine and a half years old, who three years before had had the symptoms of renal colic, whetstone-shaped microscopic crystals (fig. 3, a), Pia, 3, which, as the figure shows, might at n A^^ first sight be considered as uric acid, Oi^O^ /1^ 0^ ^"* °^ heating the cloudy urine the J>Oc^(y^(|lO^J sediment quickly dissolved. This sed- ^"^ " " iment collected on a filter and washed with alcohol gave the following reac- tions: The crystals were soluble ia water and hydrochloric acid, solution took place in nitric acid without effer- vescence, and after evaporation a yel- low residue remained. The hydrochloric acid solution on evaporation separated crystals of the form h, which were solu- ble in water. The sediment also readily dissolved in alkalies. * Loc. cit., p. 70. t Chem. Centralblatt, 1868, p. 847. Digitized by Microsoft® URINARY SEDIMENTS. 175 The urine always had a tolerably high specific gravity, and at times contained traces of albumen, but the sediment, according to Bence Jones consisting of xanthin, did not appear again later. G. Lebon* describes an interesting calculus containing xan- thin. It consisted first of all of a layer of phosphate of calcium and ammonio-magnesian phosphate one millimeter thick, then followed a second layer of calcic oxalate of equal thickness, and finally the chief mass consisting of xanthin and a small amount of urate of calcium. This inner stratum formed an amorphous cinnamon-brown mass which assumed a waxy lustre on being rubbed. The solution in hydrochloric acid on slow evaporation left a residue of beautiful hexagonal lamellae of chloride of xanthin. II. OeGANIZBD SBDrMENTS. § 50. Mucus AND Epithelium. It is well known that animal mucus is separated from the mucous membranes and contains the epithelial cells in their different forms suspended in it. Every urine contains such mucus which comes from the urinary passages and bladder, and very soon separates when at rest as a light cloud. If such urine is filtered, the mucus for the most part remains on the filter in isolated transparent colorless clumps, which shrink and form a shining varnish-like coating. The characteristic constituent of mucus is mucin, a derivative of the protein bodies, which when dissolved in a fiuid, even in small amount, imparts to it a viscid stringy quality. A solution of mucin does not coagulate on boiling (distinction from albu- men), but it does on the addition of alcohol, by which the mucus is precipitated as a fibrinous coa^lum. Acetic acid and a solu- tion of alum separate mucus in thick flakes ; the stringy mass precipitated by acetic acid has a certain resemblance to coagu- lated blood fibrine. (Funke, Taf. XL, fig. 6; 2"= Aufl., Taf. XV., fig. 6.) Mineral acids also precipitate a solution of mucin ; yet the precipitates which take place are readily soluble in a slight excess of the acid. Mucin is chiefiy distinguished from *Compt. rend., Band 73, p. 47. Digitized by Microsoft® 176 ANALYSIS OF THE UBINE. pyin, which occurs in pus, in that it is not precipitated either by a solution of corrosive sublimate or one of sugar of lead, though it is by the basic acetate of lead. In the mucous sediment of a normal urine there appear un- der the microscope, besides the distinctly nuclea,ted, variously shaped epithelial cells of the urinary passages, etc., isolated mucous corpuscles in the form of round, very granular cells, containing one or several nuclei, which do not differ from the colorless corpuscles of the blood, lymph, chyle, and pus in any essential parficular. (Plate I., fig. 4, 5, and 6; Plate II., fig. 1, 2, and 3; Plate IH., fig. 3.) If the secretion of mucus is increased by disease, the little cloud described above as occurring in normal urine is often enormously augmented, and shows large amounts of mostly well-preserved epithelial flakes and mucous clumps. If the mucous sediment which settles on standing is free from pus and consists only of mucus, the filtered urine is free from albu- men, while if pus is present at the same time the urine always contains an amount of albumen corresponding to the pus serum. (Compare Pus, § 52, B.) In gonorrhoeas the mucous corpuscles coming from the urethra differ from uric acid, etc., by their size and their clear, slightly granular appearance. In affections of the prostate the amylaceous bodies of this gland appear, and frequently, as at times after gonorrhoea, long mucous plugs, which under the microscope appear to be composed of mucous corpuscles closely adherent to each other. 1. Normal urine always contains only traces of mucin in so- lution. An increase, according to Reissner,* occurs in various acute febrile affections, as pneumonia, pleuritis, typhoid fever, intermittent fever, pulmonary and intestinal catarrhs, menin- gitis, acute delirium, and epileptic attacks with irritation of the vascular system, etc. Often the mucin alone appeared at the commencement of the fever, a few days later albumen was also found, which disappeared again after a longer or shorter time, while the mucin continued a few days longer. Cases in which there was a large amount of mucin which lasted a long time without albumen were rare. The microscope showed for the most part a large number of epithelial cells of very different * ArcWv f. path. Anat., Band 24, p. 191. Digitized by Microsoft® URINABT SEDIMENTS. 177 . sorts ; niTicous coagula were often very abundant, but at times were only sparingly present. Sometimes mucous and pus cells were entirely wanting. Acetic acid is especially valuable fortlie detection of dissolved mucin ; it causes in every urine contain- ing mucia a uniform cloudiness insoluble in an excess of the acid. Only in rare cases does a flocculent deposit occur after long standing, but if the urine before the addition of acetic acid was diluted with water to several times its volume, there results from the cloudiness, when there is not too small an amount of mucin, a tolerably coarse flocculent precipitate which settles after some hours' standing, and under the microscope appears as a uniform finely granular mass with a few uric acid crystals imbedded in it. Tartaric acid acts like acetic acid. Miaeral acids when very dilute, and added drop by drop to the urine, give a precipitate which is soluble in the slightest excess of acid. A few drops of hydrochloric acid will also dissolve the cloudiness caused by acetic acid immediately and com- pletely, when added soon after the latter. Many urines in very febrile conditions also give a cloudiness with acetic acid insoluble in an excess, but which disappears on heating and does not recur again, if the urine is sufficiently diluted with water before the addition of the acid. This cloudi- ness, which is probably caused by urates, is, therefore, easy to distinguish from a precipitation of mucin. The dissolved mucus is frequently precipitated in the form of mucous coagula at the beginning of acid fermentation, pro- bably by the free acids formed. They appear in narrow and broad curved bands containing very fine points and granules arranged in rows, and very frequently sediments of acid urates accompany them. These mucous coagula (Plate II., fig. 2) have at times a certain resemblance to granular casts from the kidney (Plate I., fig. 6), and may, therefore, give rise to mis- takes. With a little experience, however, they are both easily distinguished. 2. Epithelial cells are found in three different forms : a. Round cells from the urinary tubules of the kidney, and from the deeper layers of the mucous membrane of the pelvis of the kidney. They are for the most part swollen by the salts con- tained in the urine, and appear as complete spheres with dis- tinctly formed nuclei. 12 Digitized by Microsoft® 178 ANALTSm OF THE URINE. The epithelium of the male urethra is very similar to renal epithelium, so that the two can scarcely be distinguished by the microscope. When renal epithelium is present, the urine usually contains albumen at the same time. b. Conical and tailed cells in most cases have their origin from the pelvis of the kidney. These cells are usually twice as long as they are broad, and are broader at one end than at the other. The spindle-shaped prolongation occurs either at one end or at both. c. The flat cells come either from the vagina or bladder. In most cases they form irregular polygonal lamellae with distinct nuclei situated nearly in the centre. § 51. Blood. The occurrence of blood in the urine is not a very rare ap- pearance and its recognition presents no special difficulties. For our purpose the blood corpuscles, and especially their mi- croscopic properties, are of special importance. A. Microscopic Properties. Normal blood corpuscles are small, round, solid structures, which seen under the microscope pre- sent a shape not to be confounded with any other substance ; they appear as thick, circular, slightly biconcave, yellow disks, with rounded edges. Their size in human beings amounts to about 0-00752 mm. (Plate I., fig. 6; Plate III., fig. 1 and 2.) The normal forms, however, suffer peculiar modifications and changes due to the presence of many alkaline salts and other substances. These changes are of special importance for our purpose. 1. Action of Water on Blood Goiyusdes. According to the amount of water added and the time during which it acts, the blood corpuscles undergo various changes, which are figured in Plate III., fig. 2, proceeding from left to right. The first result of the action of water is, that the single cells swell up, at the same time assume a more lenticular shape, and finally become spherical; this takes place because their central de- pression disappears and gradually arches out, which necessa- rily causes a diminution of the diameter of the disks. The corpuscles now appear smaller, the central shadow disappears gradually, and in its place a circular one appears on the edge. Digitized by Microsoft® URINABr SEDIMENTS. 179 If the action of the water lasts for a long time, the cells be- come constantly fainter and paler, and finally appear only as hyaline bladders, which soon become entirely imperceptible and disappear. 2. Action of ScHine Solutions on Blood Corpuscles. If normal blood corpuscles are covered with a concentrated solution of a neutral salt, for example sodic sulphate, they undergo quite rapidly a strong contraction, which under the microscope is chiefly indicated by an increase of the central depression; the shadow which indicates this reaches nearer to the edge of the disk than in normal blood corpuscles. The edges are usually no longer circular, but are mostly more or less dis- torted, oblong, angular, and also not smooth, but notched or toothed. If, further, blood corpuscles, which have become in- visible by the action of water, are treated with a concentrated solution of sulphate of sodium, they become visible again, but now appear in the distorted, angular, and toothed forms Just described. (Plate HI., fig. 2, lower right side.) 3. Caustic alkalies, as well as several organic acids, as, for example, acetic acid, cause the blood corpuscles to become very much swollen and distorted, and destroy them more or less rapidly. The important constituent of the red blood corpuscles is the haemoglobin (blood-coloring matter, hsematocrystallin), which may be obtained more or less easily in a crystalline form. (Funke, Taf. X., fig. 1-6 ; 2'^ Aufl., Taf. IX. u. X.) The beautiful blood-red solution shows on great dilution (ttW)' when it is examined by the spectroscope in a layer of fluid one ctm. thick^ two absorption bands between the Frauenhofer lines D and E in the yellow and green of the spectrum. (Plate IV.) The band situated nearer D is more sharply defined, and also dis- appears later than the other on dilution. If, however, such a solution of oxyhsemoglobin is allowed to remain in a closed vessel for a time, or if the oxygen is removed from it by a few drops of sulphide of ammonium, the arterial color gradually disappears. In the spectrum the two absorption bands are now absent, and instead, about in the middle between the spectral lines D and E, there is a broad, poorly defined band. On shaking with air this disappears, and the absortion bands characteristic of oxyhsemoglobin appear again. If a solution of Digitized by Microsoft® 180 ANALTSia OF TEE UBINE. haemoglobin is heated a few minutes to 70° or 80° C, it de- composes into hsematin and coagulated albumen with change of color. Basic acetate of lead does not precipitate a solution of pure hssmoglobin. After standing a long time, especially at blood heat, a darker color and acid reaction occur, the hae- moglobin becomes converted into methsemoglobin, which is an intermediate product formed during the change of haemoglo- bin into hsematin and albuminoid matter, and which is found in old extravasations of blood and also in the urine after de- struction of the blood corpuscles. Examined with the spectro- scope an acid solution of methsemoglobin sufficiently dilute shows almost the same spectrum as an acid solution of pure hsematin. Both give only one absorption band between the lines and D, which lies rather nearer C. (Plate IV.) If the solution is rendered alkaline the bandg" draw nearer to D, and become feebler and less sharply defined. Basic acetate of lead precipitates a solution of methsemoglobin. We are indebted to Hoppe-Seyler and Stokes for these excellent reactions. B. Detection. 1. The Urine contains Blood Corpuscles. If the urine is acid, the blood corpuscles remain unimpaired a tolerably long time, or at most become somewhat crenated, but they are usually swollen and approach the spherical form. Their color is paler than in the normal condition, but they are always at the same time sharply defined, and are no longer arranged in rows. All of these changes indeed are to be attributed to the water and salts contained in the urine according to the modifications de- scribed above. (Plate I., fig. 6 ; Plate III., fig. 1 and 2.) When the amount of blood is small, the urine is allowed to stand quietly in a conical glass for a long time. The blood cor- puscles then settle to the bottom as a beautiful red sediment, and may generally be recognized as blood with the unaided eye. The clear filtered urine, when blood is present, always contains a corresponding amount of albumen also, which may be recognized according to § 23, D. If such a urine sufficiently diluted is examined with the spec- troscope, it shows the absortion bands between the lines D and E, which were described above as characteristic of hsemoglo- bin. (Manipulation : see below, 2, a.) (Plate PV.) 2. T'h£ Blood Corpusdes are destroyed; the Urine contains Me- Digitized by Microsoft® UBINABT BEDIMENTS. 181 thcemoghbin. The urine may be colored reddish brown, or even black, by methsemoglobin. It is tested as follows : a. Some of the clear filtered urine is poured into a vessel, a, fig. 4, of plate glass, with two parallel walls ; this is placed close to the slit of the spectroscope, lighted with sunlight or a bright gas or oU lamp, and the spectrum observed through the telescope, b. If the amount of methsemoglobin is not too great, and the urine consequently not too strongly tinged, the char- acteristic bands between the lines and D will appear imme- FiG. 4 diately somewhat nearer than D. (Plate IV.) On the other hand, when there is very considerable methsemoglobin, a greater or less part of the whole spectrum will be absorbed and will only become clear on dilutiag the urine under examination with water, until the absorption bands characteristic of methsemo- globin are seen. b. A second specimen of the filtered urine is heated to boil- ing. If methsemoglobin is present, a brownish-red coagulum is formed, which consists of hsematin and an albuminoid body : after drying the color becomes almost black. If we treat such Digitized by Microsoft® 182 ANALYSIS OF THE UBmS. a coagulum, preyiously washed, with alcohol containing sul- phuric acid, and heat gently, it will assume a more or less red or reddish-brown color, and after sufficient concentration will show in the spectrum the absorption bands described under a, as characteristic of hsematin and methsemoglobin. (Plate FV.) c. A third specimen of the urine under examination is treated with a little sodic hydrate, heated to boiling and allowed to stand for a time. 'The earthy phosphates which separate carry down the haamatin formed by the decomposition of the hae- moglobin or methaemoglobin, and appear sometimes as a brownish-red and sometimes as a beautiful blood-red precipi- tate, which is often dichroitic, playing into green by reflected light. This reaction does not allow of a discrimination be- tween haemoglobin, methsemoglobin, and hsematin. If the phosphate precipitate is colored by rhubarb, senna, or santonin, and not by hsematin, it is recognized by the fact that it does not, like the hsematin precipitate, become dichroitic by the action of potassic hydrate, but in time becomes violet, es- pecially when exposed to the air. d. Tannin is a very valuable reagent for precipitating small traces of blood. The fluid in question is treated with a little ammonic or sodic hydrate, then with a solution of tannin, and lastly with acetic acid until it has a distinctly acid reaction. If blood is present a distinctly colored precipitate forms, which quickly settles to the bottom of the fluid. This precipitate is tannate of hsematin. After washing and drying, it is specially fitted for the production of hsemin crystals. For this purpose a portion of the dry precipitate is placed on a glass slide, a trace of chloride of sodium is added, and then glacial acetic acid. So- lution takes place at a gentle heat, and after cooling, the well- known characteristic hsemin crystals will be found under the microscope in large numbers. (Struve.)* The reaction is ex- tremely delicate. By performing it in the manner described, Bergt succeeded in proving by the most beautiful hsemin crystals, the presence of a drop of blood in 450 cc. of urine. e. Another method for detecting blood in the urine has been given by Almen.:]: A few cc. of tincture of guiacum are mixed * Zeitschrift f , analyt. Chemie, Band 11, p. 39. f Hyiea, Band 34, 3, Stockholm, 1873. t Zeitsclirift f. analyt. Chem., Band 13, p. 104. Digitized by Microsoft® UBINABT SEDIMENTS. 183 with an equal volume of oil of turpentine, it is shaken till an emulsion is formed, and then the urine to be tested is carefully added. When the emulsion comes in contact with the urine, the guiac resin is quickly precipitated as a white, later dirty yeUow or green precipitate. If the urine contains blood, even traces merely, the resin is colored more or less intensely blue, often almost indigo blue. In normal urine or in urine con- taining albumen from pus, this blue coloration does not occur. § 52. Pus. When urine contains pus it can only be detected with cer- tainty by the microscope. A. Microscopic Froperties. Normal pus corpuscles appear under the microscope as round, pale, faintly granular bodies of variable size. It is of especial importance that a distinct nu- cleus may usually be perceived in them, which in many cor- puscles is single, but in others appears divided and multiple. (Plate I., fig. 6 ; Plate III., fig. 3.) All pus corpuscles do not have a sharp contour, but in many cases only a faint an(J indis- tinct one. 1. Action of Water on Pus Corpuscles. If fresh pus is consider- ably diluted with distilled water, the corpuscles are seen to swell up very much, and become extremely pale and delicately bordered ; at the same time their granular surface usually dis- appears, whereas the nuclei become more distinct and small dark punctiform granules are seen. (Funke, Taf. XI., fig. 4; 2"' Aufl., Taf. Xy., fig. 4.) 2. Action of Acetic Acid on Pus Corpusdes. If dilute acetic or any other organic acid, or even very dilute mineral acids are allowed to act on pus, the corpuscles swell up, so that some- times they assume double their usual size ; their surface then loses its granular appearance, the coverings become very hya- line, and not unfrequently burst, so that here and there, with a good light, their jagged and broken remnants may be distin- guished. The nuclei already mentioned beconie very distinct, of different shapes and numbers, appearing partly as simple, round, oblong, spindle and horseshoe-shaped bodies, and partly as double, triple, and quadruple ones, variously grouped accord- Digitized by Microsoft® 184 ANALYSIS OF THE URINE. ing as they are formed by division of the single nucleus. (Plate III., fig. 3, upper half.) 3. Caustic Alkalies quickly destroy pus corpuscles, but com- plete solution does not take place. The corpuscles frequently remain visible for a short time, but disappear after the addition of water, and leave only a gelatinous residue in which isolated bright or dark points may be recognized. B. Detection. Pus settles very quickly in acid urine when at rest, and when the supernatant urine has been drawn off with a siphon, it may be easily subjected to microscopic examination, (Plate L, fig. 6 ; Plate II., fig. 3 ; Plate III., fig. 3.) Purulent sediments are not very rarely accompanied by blood corpuscles, which may be recognized by their reddish color, but more surely by the microscope. In both cases the clear filtered urine con- tains corresponding amounts of albumen. (§ 28, 0.) Pus suffers an essential change in alkaline urine, which is the more impor- tant, since frequently in catarrh of the bladder, etc., alkaline urine is passed with considerable amounts of pus. Alkalies change pus into a gelatinous mucous mass, which adheres tenaciously to the wall of the vessel, and under the micro- scope pus corpuscles no longer appear, so that it may readily be mistaken for mucus. But in most cases it is possible to find in addition to this viscid gelatinous mass a tolerable number of pus cells suspended in the urine if it is examined under the microscope as soon as possible after being passed. The behavior of pus with alkalies just cited may serve for distin- guishing it from mucus. The sediment under examination, obtained by settling, is treated with concentrated potassic hy- drate ; pus is coagulated by it into the gelatinous mass spoken of, while mucus dissolves to a thin fluid with flakes. (Donne's pus test.) Since, as observed above, when pus is present, the urine always contains albumen also from the pus serum, an ap- proximate estimation of the quantity of pus may be made from, the amount of the albumen in the urine previously filtered, provided there is sufficient ground for excluding a simultaneous real albuminuria. Moreover, when blood is present at the same time, this is also to be taken into account as the source of a part of the albumen. Digitized by Microsoft® URINABY 8EBIMENTS. 185 § 53. Casts. In many diseases, but especially in Bright's disease of the kidneys, peculiar tubular or cylindrical bodies, whicli have for a long time been the subject of investigatioil, are observed in the sediment of the urine. They vary in texture more or less, for which reason Lehmann distinguishes three different kinds : 1. Tubes which appear to consist of the epithelial lining of the tubules of Belbni ; these appear in almost every inflamma- tory irritation of the kidneys, and form regular tubes in which the small cells and cell nuclei appear to be grouped almost like a honeycomb. (Plate I., fig. 4.) 2. Cylinders which appear to consist of fresh exudation, which was formed in the tubes of Bellini and has retained their form. These cylinders form granular masses which are frequently covered with blood and pus corpuscles. They appear to con- sist of fibrine, at least their ready solubility in alkalies indicates this, while the blood and pus corpuscles attached are partly destroyed and partly remain suspended in the fluid. They are always found in Bright's disease.* (Plate I., fig. 6.) 3. Finally, casts are sometimes observed, which consist of hollow cylinders with hyaline walls, and can be distinguished from the surrounding fluid under the microscope only with care. Frequently they lie together, form folds and appear as if twisted on their axis. They usually occur only isolated in the chronic form of Bright's disease. (Lehmann.) (Plate I., fig. 5.) Detection. For the certain detection of these very important structures, the urine, which in most cases contains considerable albumen, is allowed to stand several hours in a conical glass. The collected sediment, mostly white and flaky, or, when other matters are present also, forming thick masses, is first exam- ined with a power of one hundred and eighty or two hun- dred diameters, and if these structures are present they can readily be seen. At most the very hyaline cylinders mentioned under 3 may remain unobserved, but immediately become ap- parent when the object is colored yellow by the addition of a solution of iodine in iodide of potassium, or red by the addition * Frerichs, Bright's disease. Digitized by Microsoft® 186 ANALYSIS OF THE UBINE. of a not too concentrated solution of fuchsin. Since frequently only a small number of these casts occur, a number of prepara- tions must be made and each one carefuUy examined in order to be sure of their absence. These sediments are frequently accompanied by fat drops, pus, epithelium, blood, etc. Care is to be taken not to mistake for granular renal casts those mucous casts described in § 50, under mucus, which are frequently found in acid urine together with urates. (Plate II., fig. 2.) (Compare Mucus, § 50.)* Concerning cancerous and tuberculous masses, see in the second part. § 54. Spermatozoa. Spermatozoa appear under the microscope as spherical or nearly spherical elements, with a distinctly recognizable tail, which is usually pointed. They appear to have a spontaneous movement. We find them in the urine after masturbation or coitus, but they have been not unfrequently observed in the urine of typhoid-fever patients. It is very easy to find spermatozoa on account of their char- acteristic shape, which does not admit of their being confounded with anything else. At the same time spermatozoa are very indestructible, so that the diagnosis of semen in the uriae is rendered still more easy. In order to find them it is necessary to place the urine at rest for a few hours at least in a conical glass (champagne glass), since the spermatozoa then sink to the bottom with the flakes of mucus. By carefully decanting, the greater part of the supernatant fluid is removed and a drop of the sediment in the apex of the glass is placed under the microscope. If spermatozoa are present they appear in the above-mentioned tadpole - shaped form. To detect them a magnifying power of from three to five hundred diameters is necessary. They soon lose their power of motion in pure water, and in urine also, especially when strongly acid or alka- line ; the spermatozoa at the same time undergo a peculiar * C. L. Rovida, Ueber das Wesen der Harncylinder. Jahresberielit u. d. Fortschritte d. Thierchemie von R. Maly, 1872, p. 184 und 187. H. Senator, Ueber die im Harn vorkommenden EiweisskSrper und die Be- dingungen ihres Auftretens bei den verscMedenen Nierenkrankheiten, fiber Harncylinder und Fibrinausschwitzung. Virchow's ArcMv, Band 60, p. 476. Digitized by Microsoft® URTNART SEDIMENTS. 187 change of shape: they form hooks (Oesen) by the posterior part of the organism being bent forward like a loop, or coiled around the forward part. Moreoyer, the observation of Leh- mann is worthy of mention, Tiz., that urine containing semen very readily becomes alkaline, and shows in the mucous sedi- ment, even when few spermatozoa are found, peculiar, fine, laminated, very transparent flakes. Clemens has several times observed the passage of immature semen with the urine ; this consists of those seminal cells, in which the spermatozoa still lie in the envelope with head and tail attached to it ; these spermatozoa seldom showed any movement, such as is familiar in mature semen. Together with these sperm-cells Clemens often saw in the urine of patients suffering from spermatorrhoea spherical cells of 0-0033 to 0-005'" diameter filled with fine granules, which were mostly located on one side of the cell. These cells are nothing more than the mother cells of the spermatozoa. These elements are found chiefly in the last drops of urine passed by patients badly afflicted with spermatorrhoea, and also in those suffering from typhoid fever.* § 55. Fungi. Iottjsoria. Fungi and infusoria are observed under the microscope in all urine which has stood for a long time ; they are found also in fresh urine which has already begun to decompose in the blad- der, as is quite frequently the case in catarrh of the bladder. The infusoria are usually very small. Most frequently punc- tiform monads or vibriones arranged like strings of pearls and often branched are found,- and are especially abundant in urine containing mucus or albumen after standing awhile. Accord- ing to the investigations of L. Daille,t living vibriones very frequently occur in pathological freshly passed urine, in which, according to the form, size, and sort of movement, six different varieties may be distinguished. The smallest of these vibriones are -y^-h, the largest -^-^ mm. in size. They do not occur in the urine of all sick persons. Daille, however, claims to have * Canstatt's Jahresbericht, 1860, p. 385. f Journ. d. Pharm. et de Chim., 1865, 11., 450 ; also Wittstein's Vierteljahres- schrift, Band 16, p. 67. Digitized by Microsoft® 188 ANALYSia OF THE UMINE. found tliat tlie urine of patients affected witli lung diseases constantly shows such infusoria either directly or a short time after passing. I must also remark, that according to HaUier,* very different forms of fungus, such as vibriones and lepto- thrix-formations, have been frequently described as bacterise and monas crepusculum, especially by Pasteur. Hassall ob- served a second sort of infusoria occurring in the urine, the Bodo urinarius. The living moving individuals are oval or round, y^Vu" long, and ^tmtf" broad, granular and similar to mucous cells. Some times they are broader at one end and furnished at different points with one, two, or three threads or cilise. They increase by division. Among those described, they have, according to Hassall, most resemblance to the Bodo intestinalis. (Ehrenb.) They are said to pccur very frequently in albuminous urine together with vibriones. Of spores, the urinary fermentation spore is very frequently found in the form of round or oval nucleated cells, which spring especially from the decomposed mucus. These fermentation spores lie at times isolated and at times aggregated together forming rows and groups. (Plate II., fig. 2 and 4.) In the advanced stage of fermentation they frequently accompany the sediments of urates, free uric acid, and calcic oxalate. According to von Tieghem the alkaline fermentation of urine depends on the development of a Torulacea, which consists of spherical non-granular cells arranged in rows like a rosary, and showing no positively recognizable distinction between envelope and contents; they are 0"0015 mm. in diameter. This ferment appears to increase by budding, and never develops on the surface of the fluid, but either within it or on the bottom of the vessel, where it finally forms a white deposit mixed with the separated salts. According to HaUier t in the ammoniaoal fermentation only the so-called nucleated cells are active, for when he sprinkled boiled healthy human urine with the spores of penicilium, there developed from the swarms only so-called nucleolar cells in incredible numbers. The oval transparent yeast spores which form during the fer- mentation of diabetic urine, are considerably larger than the * Hauler's Gahrungserscheinungen, Leipzig, bei W. Engelman, 1867, p. 5, 66, etc. f Loc. cit., p. 64. Digitized by Microsoft® UBINABT SEDIMENTS. 189 Fig. above, and in form and development correspond to the ordinary yeast cells. Their form is usually somewhat oblong, sometimes also round, their size is variable ; all have a distinct round nu- cleus which often appears like a hole. According to Hallier spores also form in the bladder, especially leptothrix chains, from which the yeast fungus may form even within the bladder in diabetic urine. On the surface of old diabetic urine forked, branched, con- fervas threads containing spores fre- quently form, which after the urine has stood a long time often make such a thick maze that they cover the entire field. (Fig. 5.) It is asserted by Hallier and others that these more highly or- ganized fungi may under favorable con- ditions spriag from the yeast cells, but this is positively denied by De Bary and Eeess.* Besides those mentioned, Hassall has found other forms of fungi in alkaline albuminous urine. Finally, the discovery of Letzerich is worthy of notice t that more or less considerable masses of fungi, spores, and mycelium occur in the urine ia diphtheritis. The mycelium was bedded in finely granular, somewhat yellow-colored masses of exuda- tion, which floated in the urine and made it faintly cloudy. Urinary Sardnoe. have been found again by Ph. Munk in the urine of a man forty-three years old. The freshly passed urine Pig. 6. had a constantly alkaline reaction, it was cloudy, and contained a little albu- men. Under the microscope, in ad- dition to the epithelium, a few blood and pus corpuscles, vibriones, and triple phosphate, and a large number of clear white cubes of sarcinse, rounded a little on the corners, were found. (Fig. 6.) If the urine stood for a while, a very abundant whitish deposit soon formed, which consisted chiefly of sarcinse and the other bodies men- * M. Eeess, " Die Alkoholgahmngspilze," Leipzig, 1870, bei Arthur Felix, t Virchow's Archiv, Band 53, p. 333. Digitized by Microsoft® IQQ ANALYSIS OF THE URINE. tioned, and especially in the months of May and June occupied a fifteenth or a twentieth part of the whole height of the daily amount of urine when emptied into a glass. In the autumn months the sarcinse decreased, and at the end of October were almost gone. Munk found single sarcinse elements and cubes formed of eight, sixty-four, and five hundred and twelve elements. Frag- ments of larger cubes were found, especially from those con- sisting of five hundred and twelve elements, in addition to the above forms. The single elements had a magnitude of 0-0008 to 0-0016 mm.; the cubes consisting of eight elements had a breath of from 0-0016 to 0-0034 mm.; those consisting of sixty- four element, a diameter of 0-0032 to 0-006 mm.; while those consisting of five hundred and twelve elements had a diameter of from 0-008 to 0-012 mm. The sarcinse from the urine were considerably smaller than the sarcinse from the stomach. The only form of sarcinse which can be indubitably recognized is that of the cube described by Virchow, which is especially well seen when the preparation is made to roll under the microscope. No tables or plates were to be seen. The reaction of the urine appears to have no influence on the development of sarcinse ; iu this case it was constantly alkaline, in the one observed by Welker it was acid, in others occasionally neutral.* V. ACCIDENTAL CONSTITUENTS. § 56. This section embraces the changes which substances undergo on their passage into the urine. The importance of the study of these changes is at once apparent, since it gives us an in- sight into the complexity of the metamorphosis in the animal organism. Yet to obtain uniformly good results in this respect naturally a very great series of investigations are necessary, which must be accurately carried out even to the most minute detail, and indeed best by the assimilation of organic bodies ' whose chemical composition is perfectly known, and whose pro- ducts of decomposition have been accurately investigated in all * AicMv f. path. Anat. u. Physiol., Band 22, p. 570. Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OF URINE. 191 directions, because from the changes which such compounds suffer in the economy conclusions may be drawn concerning the chemical processes which are at work in the organism, and especially in the blood, in the metamorphosis of tissue. Before passing to the individual substances the following facts are to be mentioned : In general it is self-erident that only those substances can pass into the urine which, in the first place, do not serve as food, and secondly, are soluble in water and have no tendency to form insoluble compounds with the organic or inorganic constituents of the body. For these reasons, therefore, it is quite easy to find most of the soluble alkaline salts again un- changed in the urine. But if we introduce into the body a non-oxidized material which has a tendency to take up oxygen, we find it in the urine again oxidized ; such a body, for ex- ample, is sulphide of sodium, which always appears in the urine in the form of sulphate of sodium. But all substances which form insoluble or difl&cultly soluble compounds with the constituents of the body, as for example, most metals which unite with the protein matters as Orfila has found, only appear in the urine again when they have been supplied to the econo- my in very large amount. Many organic bodies, moreover, suffer in the organism simi- lar or the same changes which we are able to bring about ar- tificially by the action of permanganate of potassium or ozone, in neutral or alkaline solution. Others again become so com- pletely oxidized that it is not possible to detect either them or the products of their decomposition in the urine, while many give off oxygen and appear in the urine as lower stages of oxidation. Lastly, the length of time is to be observed which is required for the elimination of a substance with the urine. It may be assumed as a rule, that readily soluble substances will be quickly removed again from the body with the urine, yet indi- viduality appears to exercise some influence in this respect ; thus, Lehmann has observed that after a dose of ten grains of iodide of potassium no trace of iodine can be found in the urine in many persons twenty-four hours afterward, while in others it will be found often three days afterward. We will now consider the behavior of different substances in the economy. Digitized by Microsoft® 192 ANALT8ia OF TEE UBINE. I. Inoegaotc Substances. A. 8aUs of the Heavy Metals. Since tlie salts of the heavy metals form difficultly Soluble compounds with many animal matters, especially the protein bodies, they only appear in the urine again when they have been taken into the economy in large doses. Orfila found antimony, arsenic, zinc, gold, silver, tin, lead, and bismuth in the urine after large doses, while they can at other times only be found in the liver and its secretions and the solid excrements, when they are given in relatively small and frequently repeated doses. Iron, after its internal administration, can frequently be de- tected immediately in the fresh urine by the ordinary reagents. (Lehmann.) Arsenic, according to Boussin, is said to exist in the urine as ammonio-magnesian arseniate. Lead was directly detected by Moos in the urine, by means of sulphuretted hydrogen, on the third day after a daily dose of from eight to nine grains. To detect the heavy metals in the urine the same methods are to be followed which are adopted in legal cases to discover them in presence of organic matters. I therefore content myself with referring to Fresenius's guide to qualitative analysis. Mercury. Recently, electrolysis has frequently been success- fully employed to detect mercury in the urine, and on account of the importance of this subject the method made use of by Schneider for this purpose may be mentioned here. Five grams of chlorate of potassium are dissolved in one liter of the urine to be examined, hydrochloric acid is added until the reaction is strongly acid, and then it is heated on the water bath. If the color becomes dark during the evaporation, a fresh amount of the oxidizing medium is to be added, but the heat is to be continued until a specimen after the addition of hydrochloric acid has no bleaching action on coloring matters. On the con- trary, it is no advantage to continue the evaporation of the urine until the salts crystallize out, since the fluid becomes colored dark when concentration is pushed to this point. Be- sides, such highly concentrated solutions are not well fitted for electrolysis, as Schneider has convinced himself by many experi- Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OE URINE. 193 ments. In most cases very large amounts of urine are neces- sary. Schneider took the entire quantity of urine passed during from three to six days (seven to fifteen liters) for his experi- ments. After the addition of chlorate of potassium and hydro- chloric acid it was concentrated on the water bath to one-seventh or one-eighth of its volume. Schneider used for the electrolysis of the fluid thus prepared a Smee's battery of six elements (other constant chains are naturally quite as efficient), whose anode consisted of a platinum plate four centimeters broad, and whose cathode was a gold wire one millimeter thick, which terminated in a club-shaped thickened end two millimeters in diameter. For the purpose of confining the division of the mercury to the smallest surface possible the electrolysis was performed in a vessel whose breadth was greater than its height. The electrolysis was continued eighteen to twenty-four hours. The gold thread, which at the end of the experiment appears to be amalgamated when mercury is present, is tested as fol- lows: It is put into a carefully cleaned glass tube which is drawn out to a capillary point at one end, and the tube is then closed at the other. The broad portion of the tube which con- taias the metal is heated to a red heat throughout its entire length. If a sublimate is deposited on the cool part of the tube after about five minutes, it is driven by heating into the capil- lary portion, and then the metal is once more heated in order to ascertain if a new sublimate appears. Now that part of the tube which contains the metal is melted from the capillary end, so that a short piece of the wide portion remains behind as a flask-like dilatation. After cooling the dilated end is opened by nipping off the capillary end, then a little iodine is intro- duced into it by means of a glass thread, and it is again closed by heat. The iodine vapor is thus driven into the capillary part of the tube which contains the mercury and disappears ; in its place brown, red, or yellow rings appear, according to the amount of iodine introduced. If the brown rings are very carefully heated, the iodine evaporates from them, and red rings of mercuric iodide remain. The red as well as the yellow rings volatilize on being strongly heated, but immediately de- posit again on the cold portions as a red sublimate, but which under certain circumstances may be yellow. The yellow rings consist of mercurous iodide ; they occur when the amount of 13 Digitized by Microsoft® 194 ANALYSIS OF THE URINE. iodine which was added was insufficient to form mercuric iodide; if another small crystal of iodine is put into the capillary end, and heated, the yellow rings readily become red. Under the microscope the red crystals appear as four-sided octahedra, which are often so placed with their surfaces toward each other that they produce feathery crystals resembling those of am- nionic chloride. No mercury could be detected by electrolysis in three cases in which the urine abounded in iodide of potassium, and which after the addition of -chlorate of potassium and hydrochloric acid was concentrated to one-tenth. After these urines, how- ever, were treated with sulphuric acid, which contained nitrous acid and were evaporated on the water bath until the iodine was completely removed, the cathode on repeating the electro- lysis showed distinct traces of amalgamation, and the subse- quent heat tests showed the most distinct reaction for mercury. It appears advisable, therefore, in urine which contains iodides to first free it from its iodine. This is easily done by heating on the water bath and gradually adding sulphuric acid which is saturated with nitrous acid. MayenQon and Bergeret * use the following simple method to detect mercury, which, however, is not in every case certain: An iron nail is suspended in the urine which is to be examined by means of a platinum wire, then pure sulphuric acid is added until oxygen is slowly evolved. The mercury now forms a metallic deposit on the platinum wire. After about half an hour the wire is removed, washed, and then exposed to the vapors of chlorine to convert the mercury into corrosive subli- mate. If the platinum wire is then gently drawn over a piece of filter paper which has been moistened with a one per cent, solution of iodide of potassium, a red streak of mercuric iodide is obtained, which dissolves in an excess of iodide of potassium. Kletzinsky evaporates the urine which has been treated with chlorate of potassium and hydrochloric acid to dryness, and extracts the residue with ether to remove tlie corrosive subh- mate. This procedure, according to Schneider, is very uncer- tain, since some mercuric chloride combined with the alkaline * Chem. Centralblatt, 1873, p, 678. Zeitschr. f. analyt. Chem., Band 13, p. 108. Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OF UBINE. igg chlorides in tte form of double chloride is retained in the resi- due. These compounds are nearly insoluble in ether, and there- fore no sublimate can be dissolyed out by ether from the eya- porated residue of the urine when completely dried. On ac- count of the importance of this subject I give here the results obtained by Schneider : 1. In the urine of syphilitic patients who had never been sub- jected to treatment by mercury, no mercury could be detected by electrolysis. 2. The same negative result was obtained on testing the urine of individuals who had pursued a mercurial treatment a long time before. The investigations were cornmenced on different persons, fourteen days, five months, and half a year after the mercurial treatment. 3. The urine constantly contains mercury during the internal use of mercurial preparations. 4. The experiments of Schneider are by no means favorable to the views now quite generally entertained of the action of iodide of potassium on metals which are retained within the organism. In three cases where iodide of potassium was given immediately after treatment by corrosive sublimate this remedy distinctly did not increase the separation of mercury with the urine. 5. In a case of hydrargyrosis which ended fatally the urine abounded in mercury, though only 1,400 cc. could be obtained for examination. Also the brain and especially the liver con- tained it.* Thallium. According to W. Marme thallium is readily de- tected by electrolysis in the urine after the latter has been treated with chlorate of potassium and hydrochloric acid and afterward concentrated. The metal fixed in this way on a platinum wire and carefully cleansed with distilled water is brought directly into the flame of the spectral apparatus, but in this case the anode as well as the cathode is to be tested, t Cadmium is detected also by electrolysis of the urine after being treated with chlorate of potassium and hydrochloric acid. J * Schneider, iiber das chemisclie und electrolytisclie Verhalten des Quecksilbers in thierischen Substanzen. Wien in Commission bei K. Gerold's Sohn, 1860. t Zeitschrift f. analyt. Ctem., Band 6, p. 503. jzeitsclirift f. analyt. Ctem., Band 6, p. 298. Digitized by Microsoft® 196 ANALT8I8 OF THE URINE. B. Free Mineral Adds. According to the investigations of C. Gaethgens* dilute sul- plLuric acid after long use goes over into the urine partly in an uncombined state. C. Salts of the Alkalies. 1. Carbonates of the alkalies always appear again as such in the urine, although a portion is necessarily neutralized by the free acid of the gastric juice. They render the urine either neutral or alkaline. Free carbonic acid, sparkling wines, beer, and acid alkaline carbonates cause an increased excretion of calcic oxalate, and at the same time increase the amount of free carbonic acid in the urine. 2. Lithium salts, after their internal use, very readily go over into the urine. To detect the lithium a sufficient amount of the urine to be examined is evaporated to dryness and the residue heated at a moderate temperature to complete ignition. After cooling, the carbon is extracted with dilute hydrochloric acid, filtered, the colorless filtrate evaporated to dryness, treated with strong alco- hol, filtered, the alcoholic solution evaporated to dryness, and the residue now left is tested with the spectroscope. I have always succeeded in detecting lithium, after its internal use, with absolute certainty according to the above method. 3. Ammonium salts pass into the urine in part unchanged. I have made experiments on this point with a young man twenty years of age, who passed on an average of twelve deter- minations 0-6137 grams of ammonia in twenty-four hours, cor- responding to 1'9305 grams of ammonic chloride. Of a solu- tion, which in ten cc. contained exactly two grams of ammonic chloride, ten cc. were taken in the evening in a glass of water, the urine was collected for exactly twenty-four hours and sub- mitted to analysis. The experiments were continued for five days, and during this time, if we deduct the above-mentioned normal amount, 9"957 grams of ammonic chloride were elimi- nated again instead of the ten taken. 4. Ferrocyanide of potassium appears in the urine reduced to the ferricyanide. 5. Sulphocyanide of potassium appears quickly in the uriae even after taking small amounts. * Centralblatt f. d. med. Wissensohaf t. , 1873, No. 53. Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OF URINE. 197 6. Alkaline silicates, ctlorates, and borates are found again in the urine. 7. Perchlorate of potassium, according to Eabuteau, readily appears in tlie urine. To detect it the urine is completely precipitated with nitrate of silver, the excess of silver is removed from the filtrate by sodic hydrate, filtered again, evaporated to dryness, and the residue ignited. The perchlorate of potassium present thus be- comes converted into the chloride of potassium, whose amount can easily be determined in the usual way.* 8. Iodide of potassium also passes into the urine and is readily detected by the familiar starch reaction. Pierre Scivoletto moistens strips of filter paper with starch paste, sprinkles them after drying with the urine to be tested for iodine, and then suspends them in the upper part of a flask, at the bottom of which there is a little fuming nitric acid. If iodine is present, the sprinkled spots become colored blue. The following method used by Castain might be more accurate when very small amounts of iodine were present : About one liter of the urine is treated with two grams of caustic potash, evaporated to dryness, and all of the organic matter ignited. The residue is dissolved in water and tested for iodine with starch and chlorine water or fuming nitric acid. A concentrated solution of hyponitric acid in sulphuric acid is suitable to free the iodine. Or it may be set free by the care- ful addition of bromine water, and removed by shaking with bisulphide of carbon. I prefer the last reaction to all others. 9. Bromide of potassium passes into the urine readily. To detect it the residue of the urine is carefully but com- pletely carbonized. The carbon is extracted with water, the bromine present in the colorless filtrate is freed by a drop of chlorine water, and the mixture shaken with ether or bisul- phide of carbon in the usual manner. For the quantitative es- timation Caigniet uses a standard solution of hypochlorite of sodium. The colorless filtrate is acidulated with citric acid and the standard solution carefully added from a burette. The freed bromine is taken up with bisulphide of carbon which is renewed from time to time. A colorless fluid always results, *Zeitschrift f. analyt. Chem., Band 8, p. 333. Digitized by Microsoft® 198 ANALYSIS OF THE UBmE. and it is easy to hit the point at which another drop of the hypochlorite of sodium solution causes no more coloration of the fluid and of the bisulphide of carbon, by which the end of the experiment is indicated.* 10. Sulphide of potassium escapes again partly as sulphate, and partly unchanged. D. Salts- of the Alkaline Earths. 1. Soluble barium salts can be detected in the urine when they have been taken in pretty large doses. 2. Lime salts do not pass into the urine at all, or at most only in very small amount. On the contrary, S. Soborow t observed a considerable' increase in the amount of lime in the urine after large doses of the carbonate (8 to 10 grams in a day). After taking eight grams of carbonate of calcium the amount of lime in the urine increased from 0-216 to 0-73 grams, and after the internal use of ten grams of the carbonate there was an in- crease of 0'27 to 0-87 grams. An increase of lime in the urine was also obtained in a dog after the subcutaneous injection of one gram of the acetate of calcium. 3. Magnesium salts are partly eliminated with the uriae. (Kerner.) n. Oegaitic Substances. A. Free Organic Adds. 1. Organic acids, such as oxalic, citric, malic, tartaric, and gallic acids, according to Wohler, pass into the urine unchanged when they are presented to the economy in a free state. 2. Acids of the Aromatic Series. a. Benzoic acid becomes converted into hippuric acid in the economy by combining with a molecule of glycocoll and elimi- nating a molecule of water. [C„H,04 + aH,NO,= CsH^NOe + 2H0] (Benzoic acid) (Glycocoll) (Hippuric acid). Benzoic ether, oil of bitter almonds, cinnamic, quinic, and mandelic acids are also transformed into hippuric acid, and * Zeitschrif t f . analyt. Ctem., Band 9, p. 437. fCentralblatt f. d. med. Wissenscliaf t. , 1873, Nr. 39. Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OF URINE. 199 appear as such in the urine. (Frerichs andWohler; Erdmann and Marchand; Lautemann; O. Schultzen, and 0. Grabe.) Nitrobenzoic acid yields nitrohippuric acid. (Bertagnini) Chlorobenzoic acid yields chlorohippuric acid. (O. Schultzen and C. Grabe.) b. Toluic acid (/S) appears in the urine as toluric acid (Kraut) ; salicylic acid in part as salicyluric acid (Bertagnini); anisic acid as anisuric acid (O. Schultzen and C. Grabe). These acids stand in the same relation to the original that hippuric acid does to benzoic. Also, after the internal use of mandelic acid, a hippuric acid, corresponding to mandelic acid, appears in the urine. (O. Schultzen and Grabe.) c. Experiments with phtalic, amidobenzoic,'cumimc, and cu- marinic acids led to no decided results. d. Oxybenzoic and paraoxybenzoic acids, the known isomers of salicylic acid, according to the investigations of Maly * do not take up simple glycocoll in the organism, but methyl- or ethyl- glycocoU, and then appear in the urine as methylated or ethyl- ated hippuric acid. e. Salicylic acid, as already mentioned above, goes over only in part as salicyluric acid, another part passes from the economy unchanged. After the internal use of 0'3 gram of salicylic acid it could be detected in the urine in two hours, but was still present after twenty hours. (Kolbe.) To test urine for unchanged salicylic acid it is treated with a solution of ferric chloride drop by drop. The first drop of an iron solution always causes an abundant separation of white phosphate of iron, but as soon as this is precipitated the in- tense violet reaction with salicylic acid appears on further ad- dition of the iron salt. O. Schultzen and C. Grabe t from their investigations of this subject draw the conclusion that all aromatic acids in which the group €H(?2 directly replaces one atom of hydrogen in ben- zol, are transformed in the economy to the corresponding hip- puric acid, while in those acids which contain a complicated side chain, as cinnamic and mandelic acids, this side chain becomes oxidized, so that the hippuric acid corresponding to * Jahresbericht lib. d. Fortscliritte der THerchemie, 1873, p. 137. t Annalen d. Chemie u. Pharm., Band 142, p. 345. Eeichert's und Du Bois- Reymond's Archiv, 1867, Heft 3. Digitized by Microsoft® 300 ANALYSIS OF THE UBINE. the one ingested does not appear in the urine, but that corre- sponding to the product of its oxidation; consequently all aromatic acids yield in the economy so-called hippuric acid, that is, glycocoU substitution products. 3. Pyrogallic acid, which, according to G. Jiidell,* in large doses has an intensely poisonous action, goes over into the uriae undecomposed. 4 Tannic acid is changed to gallic acid and appears as such in the urine. 5. Camphoric acid is eliminated unchanged with the urine. 6. Succinic acid was found again in the urine. (Meissner and Shepard.) Considerable amounts of succinic acid occurred after par- taking largely of asparagus. Here it was evidently formed by the decomposition of the asparagin (amidosuccinaminic acid) in contact with ammonia. 7. Uric acid undergoes the same decompositions in the econo- my which we are able to produce artificially by the action of peroxide of lead, or better still, of permanganate of potas- sium. In the perfectly normal organism, when the respiration is unimpeded, uric acid is decomposed by the absorption of water and oxygen for the most part into urea and carbonic acid. When the respiration is more or less disturbed, oxalic acid accompanies the above products of decomposition, and under certain circumstances allantoin also, which Stadeler and Fre- richs saw really occur in artificially disturbed respiration. (See Uric Acid, § 6, D, 3 and 5.) 8. After taking abietic acid or other resins, such as turpen- tine, balsam copaiba, etc., according to Maly, abietate of sodium is eliminated with the urine. In such a urine a white cloudi- ness, not unlike a precipitation of albumen, is produced by nitric acid, which, however, immediately disappears on the addition of alcohol. B. Inidifferent Substances. 1. Alcohol. According to the investigations of Lieben,t al- cohol is constantly eliminated in the urine after partaking of spirituous drinks, and can be separated by fractional distilla- * Hoppe-Seyler, Med. ctem. Untersuchungen, Heft 3, p. 423. tAnnal. d. Cliem. u Pharrn., 7, Supplementbd. , p. 336. Digitized by Microsoft® AGOIDENTAL CONSTITUENTS OF URINE. 201 tion, yet the amount of alcohol which appears in the urine is always relatively small, both after small and large doses. 2. Phenol (carbolic acid) appears in the urine after both its external and internal use, and, according to Waldenstrom and Almen, Salkowski, and others, may be readily detected in the distillate of the urine acidulated with sulphuric acid by means of the usual reactions* It is well to shake the distillate ob- tained with ether, evaporate the ether, and test the residue for phenol. (§ 9, 0.) 3. Chloroform is eliminated with the urine, and such a urine reduces Fehling's copper solution on heating. ' To detect and estimate it quantitatively, according to Marechal, a stream of air is forced through the urine to be examined, and, saturated with chloroform, is conducted through a red-hot porcelain tube. The chlorine, which by this process is set free from the chloro- form, will precipitate chloride of silver on being passed through a Liebig's bulb tube filled with nitrate of silver solution, and from the weight of the chloride the amount of chloroform which was present may be calculated, t 4. Chloral, according to the investigations of von Mering and Musculus,:t is eliminated unchanged in the urine to a very small extent, but by far the greatest part combines with constituents of the economy, and appears in the urine as urochloralic acid (G;H„Cl„Oe.) After taking chloral (five to six grams) the urine has a strong acid reaction and reduces an alkaline solution of copper. The detection of chloroform or formic acid in the urine did not suc- ceed, but on the other hand small quantities of chloral were detected by means of Hofmann's isocyanphenyl reaction. Sugar was not present, but a not inconsiderable amount of an organic acid which turned a ray of polarized light to the left, and to which Von Mering and Musculus have given the name urochlo- ralic acid, was detected. Urochloralic acid is separated by the following treatment: The urine containing chloral is evaporated on the water bath, treated with sulphuric acid, and shaken with a mixture of two volumes of ether and one volume of alcohol. The ether is dis- * Zeitschrif t f . analyt. Chem. , Band 10, p. 125. t Zeitschrift f. analyt. Chem., Band 7, p. 393 und Band 8, p. 99. % Berichte d. deutsch. chem. Gesellschaf t, Band 8, p. 663. Digitized by Microsoft® 203 ANALYSIS OF THE URINE. tilled off, tlie residue neutralized with potassic hydrate, evapo- rated, taken up with 90 per cent, alcohol, filtered, the filtrate precipitated with ether, the precipitate dissolved in water, decolorized with animal charcoal, and evaporated to a small volume. On cooling a crystalline mass separates, which for the most part consists of the potassium salt of urochloralic acid. By washing the salt, which has been dried over sulphuric acid, with absolute alcohol, it is freed from the urea and hippurate of potassium which are mixed with it. The pure potassium salt is then dissolved in as little water as possible, acidified with hydrochloric acid, this solution shaken with the mixture of ether and alcohol above mentioned, and filtered. Most of the chloride of potassium remains on the filter, and the rest sepa- rates if the filtrate is treated with a great excess of ether, and is allowed to stand forty-eight hours. The filtrate is evaporated and the residue freed from chlorine by moistened oxide of silver. The excess of silver oxide which has gone into solution is quickly precipitated by sulphuretted hydrogen, and the filtrate evaporated to a syrupy consistence. The acid crystallizes after twelve hours. The potassium salt gave 12 '56 per cent, of potas- sium ; the barium salt 19"57 per cent, of barium. Urochloralic acid crystallizes in colorless silky needles, which have a starlike arrangement like tyrosin, and readily dissolve in water, alcohol, and a mixture of alcohol and ether, but are insoluble in ether. On boiling it reduces an alkaline solution of copper, silver, and bismuth, and colors yellow a solution of indigo made feebly alkaline with carbonate of sodium. Its so- lution turns the plane of polarization toward the left, and in- deed the specific power of rotation of the potassium salt for yellow light was found to approximate («) = —60". The urine, after the introduction of five to six grams of chloral hydrate into the organism, turned polarized light about 5° to the left; it contained, therefore, about ten grams of this acid in the liter. Urochloralic acid on heating with anilin and an alcoholic solu- tion of potassic hydrate evolved no isocyanphenyl. 5. Hydrocarbons of the Benzol Series.* a. Benzol is oxidized in the system and appears in the urine again as phenol (carbolic acid). * O. Schultzen u. B. Naunyn, Reichert's u. Du Bois-Reymond's ArcMv, Jatrg. 1867, Heft 3. Digitized by Microsoft© ACOIBENTAL CONSTITUENTS OF UBINE. 203 b. Toluol is oxidized to benzoic acid in tlie economy, and appears in the urine as hippuric acid. c. Xylol in tlie system is first oxidized to toluylic acid, and appears in tlie urine as toluric acid. d. Camphorcymol (OioHi^) after its internal administration is converted into cuminic acid (propylbenzoic acid) according to tlie investigations of Nencki and Ziegler.* To separate these acids the urine is treated with an amount of subacetate of lead which is insufficient to completely precipi- tate it, it is filtered, the filtrate concentrated to a syrup, pre- cipitated with alcohol, the alcoholic solution evaporated, acidu- lated with dilute sulphuric acid, and shaken with ether. The ether leaves an acid oil behind, which solidifies after long stand- ing. It is saturated with carbonate of barium, treated with animal charcoal, and the concentrated filtrate treated with hy- drochloric acid, which separates the acid in crystals which are purified by re crystallization. e. Mesitylen (trimethylbenzol), according to Nencki,t readily becomes converted into mesitylenio acid in the economy, and is eliminated in part as such, and in part united with glycocoU as mesitylenuric acid. Both can be separated by distillation with aqueous vapor, during which the volatile non-nitrogenous acid passes over and deposits in the receiver. f. Mtrotoluol has an excessively poisonous action. Parani- trotoluol, which in dogs, at least, manifests no poisonous action, becomes paranitrobenzoic acid to a very slight extent, and is found in the urine as such. The largest part of the paranitro- tolnol, on the other hand, is transformed into paranitrohippuric acid and appears in the urine as paranitrohippurate of urea. (Jaffe.):]: 0. Salts of the Organic Acids. 1. Neutral salts of the alkalies with the vegetable acids are oxidized in the economy just as if they were consumed in oxy- gen gas. They appear in the urine as carbonates, therefore, render it alkaline, cause an efi'ervescence with acids and a sepa- ration of the earthy phosphates. If the salts at the same time * Berichte der deutsch. chem. Gesellschaft, 1873, p. 749. t Archiv f. experim. Pathol, u. Pharmakol., 1873, p, 430. X Berliner Bericite, Band 7, p. 1673. Digitized by Microsoft® 204 ANALYSIS OF THE UBINE. haTe a purgative action, or if they are taken witli much animal food, the urine in the former case is often not at all, and in the latter only slightly alkaline. Moreover, other circumstances, especially certain diseases, exercise an influence on these ordi- nary appearances. 2. The ethereal sulphates of sodium, according to the investi- gations of E. Salkowski,* pass over into the urine unchanged. Para- and meta-sulphophenate of sodium likewise leave the economy unchanged. After the internal use of these salts the urine is colored deep blue after the addition of a trace of ferric chloride, as happens with phenolsulphuric acid. Benzol sulphate of sodium provoked much diarrhoea in dogs, and could not be detected in the urine. The urine contained benzolsulphuric acid unchanged after the injection of two grams under the skin. D. Organic Bases, etc. 1. Quinine can be easily found in the urine after the admin- istration of not too small doses. a. According to the interesting investigations of Kerner,t quinine can be most easily and surely detected in the urine, even when diluted two million times, by means of its fluorescent properties. Since, however, the chloride of sodium which is present prevents the fluorescence, the chlorine must be re- moved first, which is done most efficiently by means of a con- centrated solution of mercurous nitrate. Twenty-five to fifty cc. of urine are treated with the reagent until a precipitate no longer takes place and there is a slight excess of the reagent present, it is filtered and the precipitate washed. Of the origi- nal color of the urine only a pale yellow is left, and when not too small amounts of quinine are present, the fluorescence can be perceived by daylight during the filtration. If the fluid is placed in the fluorescope constructed by Kerner and repre- sented in fig. 7, the fluorescence will be seen most beautifully, even at a dilution of two million times, as soon as the induction current passes through the Geissler fluorescence-tube, and the cover is closed, if the observation is made through the pyramidal tunnel. For the sake of comparison it is well to fill only one * Pflilger's Archiv, Band 4, p. 91. f Archiv f. Physiologie, Band 3, p. 300. Zeitschrift f. analyt. Chem., Band 0, p. 134 im Auszug. Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OF URINE. 205 arm of the U-shaped tube with the urinary fluid, and the other with water. The reaction is still more delicate if the urinary Pig. 7. fluid is completely decolorized before testing ; this is done most simply by conducting a few bubbles of sulphuretted hydrogen into it, when the sulphide of mercury takes up the rest of the coloring matter. Herapath gives the following method for the same purpose : The urine is rendered alkaline with a little potassic hydrate ; it is shaken with ether, which takes up the quinine, after which the ether is evaporated. Then a test fluid is prepared of three drachms of acetic acid, one drachm of rectified spirit, and six drops of dilute sulphuric acid. One drop of this mixture is put on a glass slide, a little of the ether residue is added to it, and then a very small drop of an alcoholic solution of iodine is brought in contact with it by means of a glass hair. If quinine is present, a cinnamon color appears immediately, caused by the iodide of quinine, and later sulphate of iodo-quinine is ob- tained, which is remarkable for its polarizing properties, and which is recognized under the microscope. Sulphate of iodo- quinine crystallizes in extremely thin plates, whose power of polarization is so strong that they can be used instead of tour- maline plates. Two plates as thin as gold leaf, when they cross each other at a right angle, allow no light to pass through.* * Journ. f. pract. Chem., Band 96, p. 87. Digitized by Microsoft® 206 ANALYSIS OF THE UBINE. According to Binz, quinine can be detected in urine, when present in the proportion of one part to 40,000 or 50,000 parts of urine, by means of a solution of two parts of iodine and one part of iodide of potassium in forty parts of water.* b. By the method of Vitali and E. Salkowski, the urine is made alkaline with ammonia and shaken with ether. After the addition of a drop of hydrochloric acid the ether is evaporated, the residue is dissolved in water, rendered ammoniacal again, and this solution shaken with ether a second time. The resi- due which now remains, after the evaporation of the ether, is used for the familiar reaction with chlorine water, and am- monia. 2. Thein and theobromin cannot be detected again in the urine. 3. Anilin was not found again by "Wohler. 4 AUoxantin, according to Wohler, appears to break up into urea and other substances. 5. AUantoin does not pass into the urine ; it also causes no increase of the calcic oxalate, but is probably decomposed into carbonic acid and urea. 6. Urea passes off with the urine again unchanged. 7. Guanin causes a considerably increase of the urea, but ia very large doses it passes off partly with the fsBce'S. 8. GlycocoU and leucin, even when taken into the economy in large doses, are eliminated again in the form of urea.t 9. Sarkosin changes in the economy partly to methylhydantoic acid, and partly takes up the sulphamic acid group and appears in the urine as a body containing sulphur. Two well-charac- terized bodies appear in the urine after taking a sufficient amount of sarkosin, which, on heating with hydrate of barium, decompose into carbonic acid, ammonia, and sarkosin, or sul- phuric acid, ammonia, and sarkosin. (Schultzen.)| Schultzen obtained these compounds from the urine by the following procedure : The urine passed within the next two hours after their ingestion was completely precipitated by basic acetate of lead, the filtrate was shaken with oxide of sil- * Zeitsclirif t f. analyt. Chem., Band 9, p. 538. f 0. Schultzen und Nencki. Bericlit d. deutschen chem. Qesellsohaft, 1869, p. 566. :|; Berliner BericMe, Band 5, p. 578. Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OF UBINE. 207 ver, it was filtered off from the excess of oxide and chloride of silver, and treated with sulphuretted hydrogen. The filtrate from the metallic sulphides was evaporated to a syrup, treated with dilute sulphuric acid in excess, and frequently shaken with large amounts of ether. The ether left a colorless syrup which contained both bodies. By boiling with carbonate of barium and precipitating the concentrated solution with abso- lute alcohol, the barium salt of the compound of sarkosin with sulphamic acid separates, while the alcoholic solution after evaporation leaves as a residue the carbamic acid derivative in magnificent tabular crystals as clear as glass. According to recent investigations by Baumann, von Mering,* and Salkowskijt sarkosin for the most part leaves the economy unchanged and appears as such in the lirine again. But since methylhydantoic acid readily becomes methylhydantoin by the separation of water, Salkowski considers that the occurrence of this body in the urine is possible after taking sarkosin. Lastly, a part of the sarkosin (methylglycocoU) may be changed into methylurea, just as glycocoU changes into simple urea. Moreover, it must be mentioned that, accordiiag to the inves- tigations of Hoppe-Seyler and Baumann, methylhydantoic acid is readily formed, if sarkosin is warmed a long time with urea and an excess of baryta. Sarkosin can be detected in urine which has been first treated with basic acetate of lead, then freed from the excess of lead, evaporated, and fractional precipitation made with alcohol or rather a mixture of alcohol and ether. By treating with hydrate of copper, well-crystallized sarkosin-copper is produced. If this is dissolved in water to which has been added a drop of hydrochloric acid, the copper precipitated with sulphuret- ted hydrogen, and the hydrochloric acid with oxide of silver, the filtrate yields crystals of sarkosin after evaporation. (Sal- kowski.) 10. Taurin behaves in a similar manner in the economy. A small portion goes over into the urine unchanged, the largest portion takes up the carbamic acid group and appears in the urine as taurocarbamic acid, which crystallizes in shining quad- * Berichte d. deutsch. chem. Gesellschaft, Band 8, p. 584. f Berichte d. deutsch. chem. Gesellsohaft, Band 8, p. 638. Digitized by Microsoft® 208 ANALT8I8 OF THE URINE. rilafceral leaflets, and on being treated with baryta water at 130° or 140° C. decomposes into carbonic acid, ammonia, and taurin. This acid can be produced artificially from taurin and cyanate of potassium at a gentle heat. (Salkowski.)* To detect taurin in the urine it is precipitated with basic ace- tate of lead, filtered after standing several hours, the filtrate freed from lead with sulphuretted hydrogen, evaporated and precipitated with absolute alcohol. The alcohol is quickly poured off from the precipitate which has taken place, and left at rest, when after twelve to twenty-four hours the taurin will separate in a crystalline form.f 11. Acetamid leaves the body rapidly and unchanged.^ 12. Amygdalin cannot be found again with certainty, but the urine, according to Lehmann and Eanke, contains considerable quantities of formic acid. 13. Salicin is decomposed as if by oxidizing agents. The urine contains salicylic hydride, salicylic acid, and saligenin, but no sugar and no phenylic acid. 14. Santonin. After using santonin the urine resembles one containing biliary coloring matter. A characteristic is that the yellow or greenish color of the urine becomes a cherry red or purple red after the addition of potassic hydrate. The color does not disappear on boiling, but it does on the addition of acids, and is restored again by alkalies. According to Mialhe this coloring matter appears to be a product of oxidation, since santonin on boiling with nitric acid gives a solution which ex- hibits a green color after dilution with water, and which changes to an orange red after the addition of potassic hydrate. § 15. Strychnia, according to O. Schultzen, and morphia, ac- cording to the experiments of Bouchardat and Dragendorff,! even in large amounts, pass into the urine. 16. Veratria, according to Masing,! passes into the urine in considerable amount. * Berichte der deutsoh. chem. Gesellschaft, Band 6, p. 1191. f Salkowski, Virchow's ArcMv, Band 58, p. 460-509. X 0. Schultzen and Nencki, loc. cit. § Natta und Smith. Zeitschrif t f . analyt. Chem. , Band 4, p. 494, und Band 10, p. 254. II Pharm. Zeitschrift f. Russland, 1868, Heft 4. 1 Zeitschrif t f. analyt. Chem., Band 8, p. 240. Digitized by Microsoft® ACCIDENTAL CONSTITUENTS OF URINE. 209 17. Asparagin (amidosuccmamic acid) does not pass into the urine unchanged. It decomposes in the economy into succinic acid and ammonia, both of which appear in the urine. (Hilger.) At the same time, after taking asparagin, as well as asparagic acid, the amount of urea is increased in the urine. (Von Knie- riem.) 18. Indol after its subcutaneous injection becomes converted iato indican, and appears as such in the urine. (Jaffe, Nencki, and Masson.) Oxindol and dioxindol become changed into red coloring matters, which resemble those obtained by the oxidation of aqueous solutions of oxindol and dioxindol in the air. (Nencki and Masson.) See page 69. 19. After taking isatin the urine contains a coloring matter which in all of its properties corresponds with indigo red (urrho- din). (E. Niggeler.) To detect alkaloids in the urine the same methods are to be used which are employed in legal cases to separate these sub- stances.* E. Coloring and Odorous Matters. Most coloring and odor- ous matters pass into the urine unchanged or but slightly modified. Wohler found in the urine the pigments of indigo, madder, gamboge, rhubarb, logwood, turnips, and bilberries, besides the odorous matters of the valerian, garlic, assafoetida, castor, saffron, and turpentine. On the contrary, he did not find camphor, resins, empyreumatic oils, musk, ether, cochineal, litmus, sap-green, and alkanet coloring matter. On the other hand, according to investigations of E. Nigge- ler,t indigo blue passed through the intestinal canal unchanged and caused no increase of the indican in the urine. * Fresenius, Qualitative Analyse, 13'® Aufl. , p. 458. f Jahresbericht f . TMerchemie, Band 4, p. 330. u Digitized by Microsoft® DIVISION SECOND. quantitative estimations. § 57. Estimation op the Amount of Ueine Secketed in a Given Time. It must be remembered tliat the determination of the amount of urine passed in a given time is the basis of all other quanti- tative estimations, and should not be neglected in any case. Therefore, the amount of the urine, and the time during which it was passed, must be annexed to every analysis of urine. These determinations can be made either with the balance or by measuring, yet only the latter method is now in general use. For this purpose the cubic centimeter, one thousand of which are equal to one liter (1 liter = 2 pounds, or 1,000 grams of water), always serves as the unit of measure. If at the same time we know the specific gravity of the urine, the amount of which has been determined by measurement, it can be readily ■expressed by weight, since it is only necessary to multiply the uumber of cubic centimeters found by the specific gravity of the urine ; 1,000 cc. of urine of 1-030 sp. gr., therefore, weigh 1,030 grams. The measurement of the amount of urine should always be made in graduated glass cylinders, several of which, small and large, should be at hand. 1. To determine the amount of urine of twenty-four hours a measuring vessel which holds at least 2,000 cc. (2 liters), and is graduated into 100 cc. divisions, is needed. Such a one may be easUy prepared by accurately weighing into a preserve jar of the proper size 100 grams of water, and carefuUy markiQg the position of the fluid with a file or diamond; then 100 grams of water are again weighed into it and the point marked 210 Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 211 again ; this process is continued until the whole glass is grad- uated up to 2,000 or 3,000. This vessel can be used directly for collecting the urine in twenty-four hours ; it must be care- fully covered with a glass plate, however, on which a thin layer of tallow, or, better still, wax, has been spread, and kept in a cool place, so that there shall be no evaporation of water in the first place, and in the second, that the decomposition of the urine shall not be hastened by heat. With these vessels it is necessary to judge of the amount between each 100 cc, so that an error of 10 to 20 cc. may occur ; if we wish to avoid this, the urine must be collected in another vessel, and then the measur- ing glass filled exactly to a file-mark, and the rest measured off in a smaller graduated cylinder. 2. To determine the amount of urine secreted ^jg g. during a short but definite time, finely gradu- ated cylinders with a foot are better; such a one holds 200 to 300 cc, and must be divided into single cubic centimeters. (Fig. 8.) They serve for determining the amount of urine for each hour very accurately. According to the object of the examination, sometimes the first, and sometimes the second ^ determination is made ; and it is to be remarked that the collection of twenty-four hours is better suited to ob- serve large, long-continued differences in the secretion of urine, and is, therefore, used in most investigations of disease. The determination of the amount of urine passed in a short time, however, allows transient differences in the secretion to be ob- served, and is, therefore, better adapted for studying the action of transient influences on the urinary secretion. Lastly, we must mention that the urine must be collected and analyzed several days in succession in all examinations in which it is desirable to obtain an average value, and the mean of the results thus obtained must be taken. § 58. SpEcmc Gbavity. 1. By the Arceometer (Urinometer). Although only approxi- mate results can be obtained for the true specific gravity of a urine by means of an araeometer, yet its use is perfectly legiti- Digitized by Microsoft® 212 ANALYSIS OF THE XJBINE. Fig. 9. tm ums mate for a physician's purposes. Such an araeometer should al- low the specific gravity of the urine to be accurately determined between I'OOO — the sp. gr. of water — and at least 1"040 — about the highest sp. gr. which human urine reaches — even to half a degree ; then it ought not to be too large, so that it may serve for small amounts of urine also. To obtain the greatest possi- ble accuracy with these instruments, it is well to divide the specific gravities of I'OOO to 1'040 on two araeometers, so that one shall run from I'OOO to 1*020, and the other from 1"020 to 1"040; the possibility will then be attained of being able to de- termine halves and quarters of a degree. All instruments of this sort, however, only give correct re- sults at a stated temperature for which they are constructed; if, therefore, we wish to be very accurate, it is first necessary before testing to bring the urine to this tem- perature. According to some experiments by Siemon, the specific gravity of a urine which at + 12° C. was 1-021, at +15° C. sank to 1-020, and at +18° C. to 1-019, so that a difference of temperature of 3° C. cor- responds to about a degree of the urinometer. Beneke arrived at the same results. At my request, Mr. Niemann, of Alfeld (Germany), now constructs urinometers which are furnished with a small thermometer in the float, on which the normal temperature at which the apparatus is constructed is designated by a red line. The scale on these uri- nometers is considerably longer than those made by Greiner of Berlin (Germany). The single degrees are large, distinct, and marked with black marks, while the half degrees are marked quite distinctly with red lines, so that an accurate reading is very much facili- tated. I have had for some time two such urinome- ters in use and am pleased in every respect with them, and therefore recommend them to those who are en- gaged in urinary analysis. (Fig. 9.) To determine the specific gravity with an arseometer, a suitable upright cylinder is four-fifths filled with the clear filtered urine, all bubbles of air are removed with a glass rod, or better with blotting paper, and the clean instrument is then slowly introduced into it. The cylinder Digitized by Microsoft® Q UAWTITA TIVE E8TIMA TI0N8. 213 must necessarily be of such a width that the urinometer can freely float in the fluid and not touch the sides of the glass at any point. The reading is accomplished most accurately when the eye is brought to a level with the lower part of the surface of the fluid, and this is accomplished when the pos- terior edge of the surface of the fluid can no longer be seen ; the point at which the plane of the fluid cuts the urinometer scale is the one which should be read ofl". When it is not rightly held before the eye, either too low or too high, the sur- face of the fluid appears to be in the form of an ellipse. The araeometer is then pressed a few degrees deeper into the urine, allowed to come to rest, and then read off a second time as a correction. Carried out in this way, the results with a good araeometer, such as Niemann furnishes, are very accurate. The araeometers of Greiner, of Berlin, have too short scales. 2. With the MoTir- Westphal Balance. This ingenious and ac- curate instrument for determining the specific gravity depends on the principle that the loss of weight which the same body suffers in different fluids is proportional to the specific gravity of the fluid. On one arm of the balance, fig. 10, the glass sinker A, which has the form of a small thermometer, hangs by means of a fine platinum wire, and is exactly equipoised by the other arm of the balance. The arm of the balance, on which the glass sinker A hangs, is divided into ten equal parts. B, C, D, and E represent the forms of the weigths, made of brass and aluminium, which belong to it. The weights B and C each weigh exactly as much as the loss of weight v, which the glass sinker A suffers in water, while D is exactly one-tenth of this Fia. 10. Digitized by Microsoft® 214 ANALYSIS OF TEE UBINE. loss of weiglit, and the weigltt E made of aluminium weighs ex- actly one one-thousandth of v. If the specific gravity of the urine is to be determined with this balance, the glass cylinder G, in which the sinker hangs, is filled with it. The weights are then so placed that the lever stands perfectly horizontal, when the sinker is wholly immersed ; this is readily determined by the two points at F. For example, if the weight B must be hung on the division 10 of the lever, the weight D, which is ten times lighter on the division 2, and the aluminium weight E, which is one hundred times lighter on the division 5 in order to restore the equipoise, the specific gravity of the urine is 1"025. The mechanician Westphal in Celle (Hanover, Germany) fur- nishes these balances of most excellent workmanship at very moderate prices. 3. With the Ficnometer\ This method is grounded on the fact that the specific gravity of a fluid is obtained by dividing the absolute weight of a given volume of the fluid examined by the absolute weight of an exactly equal volume of distilled water. For this purpose a glass with as thin walls as possible, closed with a ground-glass stopper, carefully cleaned and dried, and holding 40 or 50 cc, is weighed on a fine chemical balance, first while empty, and its weight noted. It is then filled perfectly full with distilled water and all of the air bubbles are carefully removed, the stopper is put in air-tight, and if no bubbles are seen, the flask is carefully dried on the outside, first with a linen cloth and then with blotting paper, and it is again weighed. If the weight of the empty glass already known is subtracted from this weight, the exact absolute weight of the volume of distilled water which the glass can contain is obtained. The weight of this amount of water as well as the temperature at which it was obtained is noted once for all. If it is desired to ascertain the specific gravity of a urine, the empty glass is repeatedly rinsed out with it and then filled with the urine, observing the above precautions, closed, carefully dried as mentioned above, and the weight determined; from this gross weight that of the empty flask is subtracted, and the absolute weight of the urine is thus obtained, which corre- sponds exactly to the volume of distilled water found in the first experiment. From these data the specific gravity of the urine Digitized by Microsoft® Q UANTITA TIVE E8TIMA TI0N8. 215 is readily reckoned, since it is only necessary to divide its ab- solute weight by that of the distilled water already known, in order to obtain as a quotient the specific gravity of the urine in question. An example may serve to explain this : The flask with distilled water weighs 80 grams. The flask alone " 30 " It therefore holds The flask with urine weighs The flask alone " 50 " of water. 81-3 " 30-0 " It contains, therefore, 51-2 " of urine. The specific gravity of the water = l-OOO. We then have the proportion : 50 : 51 -a =1-000 (sp. gr. of water) : x (sp. gr; of the urine). 51-3 X 1-000 50 a -034. Instead of an ordinary flask it is better to use the picnometers made for this pur- pose (fig. 11), which have many advantages. These glasses are easy to weigh, they hold a tolerably large amount of fluid, and obviate the shutting in of air bubbles, since the latter can escape through the fine capillary tube in the ground tube-stopper a. Per- fectly complete picnometers have a small thermometer in this tube, by means of which the temperature may be determined at the same time. The calculation is just the same as above ; the weight of the dis- tilled water which the picnometer can hold is determined once for all. Pig. 11. Digitized by Microsoft® 216 ANALYSIS OF THE UBINE. § 59. Estimation of the Water and op the Total Solids IN Solution. In the estimation of the solid residue of urine many difficul- ties stand in the way, which are caused in the first place by the readiness with which the urine decomposes, and secondly by the very hygroscopic character of the residue. According as greater or less accuracy is required, sometimes the first and sometimes the second method is chosen. 1. Ten to fifteen grams or cc. of urine are weighed or mea- sured into a rather small accurately- weighed porcelain crucible (fig. 12), which can be Fro. 13. closed with a cover, and eva- porated to dry- ness over the water bath. Instead of a crucible a small glass cup with a ground edge which can be hermetically sealed by means of a ground-glass plate (fig. 13) may be used. Naturally the residue cannot be ignited in this vessel. (§ 60.) A water bath adapted to all of these purposes is shown in figure 14. It is made of strong sheet copper, and when in use Pig. 14. is lialf filled with water, which is kept at the boiling point by means of a small spirit lamp. It is furnished with rings of difi'er- ent sizes for evaporating dishes and cruci- bles of various diameters ; these rings are simply laid on the top. The diameter from a to & is from four to six inches. The residue thus obtained is not yet entirely freed from water, and must, therefore, be dried a still longer time at 100° 0. The air bath, figured in the adjoining cut (fig. 15), will serve for this purpose. The crucible containing the evaporated residue is placed in the wire frame e, and the apparatus heated with a small spirit lamp placed underneath. By means of a ther- mometer d, fastened in with a stopper at the hole c, the Digitized by Microsoft® QUANTITATIVE ESTIMATIONa. 217 temperature is determined, and can easily be kept constant with very slight variations. After the urinary residue has been dried in this man- ner one or two hours, the crucible is covered and al- lowed to cool in a desiccator over concentrated sulphuric acid, since its contents would attract water again from the air with great eagerness; fig. 16 represents such an apparatus, in which 6 is a holder made of lead wire on which the crucible is placed. The vessel is hermetically sealed by a glass plate smear- ed with tallow. The crucible Pia. 15. Pig. 16. is carried to the scales in this apparatus and weighed quickly. It is now for a second time exposed for a while to a temperature of 100° C. and weighed again; if it has not considerably decreased in weight, the operation is finished, and after subtracting the weight of the crucible the amount of residue is obtained, and is reck- i'^^^'wB^ii oned for the whole quantity of urine. i ^ ' 'IwHI^V -'-^' further, the weight of the residue is ^-Cr ■ JjjaH^"^ subtracted from that of the quantity of urine taken, the remainder is the amount of water evaporated. Example : I. Amount of urine in twenty-four hours = 1,000 cc. of a sp. gr. 1 ■035. Ten cc. were evaporated to dryness and the residue dried at 100° C. Crucible with the residue = 24-891 grams. Crucible alone = 34-350 " Eesidue = 0-541 0-541 grams of residue is contained in 10 cc. of urine, so that in 1,000 cc. of urine there are 54-1 grams. Digitized by Microsoft® 218 ANALY8ia OF THE URINE. II. 1,000 ec. of urine of 1-034 sp. gr. = 1024-0 grams. Of this the residue = 54-1 " Evaporated water = 969-9 " 2. Even when carried out with the greatest care, this method described under 1 gives inaccurate results, since during the evaporation and drying the acid phosphate of sodium has a destructive action on the urea and decomposes it partially into carbonic acid and ammonia. The latter combines with the acid phosphate of sodium to form ammonio-sodic phosphate, a com- pound which is again decomposed at 100° C. with the evolution of ammonia. As long as the evaporation and drying is con- tinued, therefore, an uninterrupted evolution of ammonia is observed, which proceeds from the decomposed urea, while the residue always retains its acid reaction. If the evaporation and drying is carried on in an apparatus in which the ammonia Fig. 17. which is set free can be collected and estimated, a satisfactory result is at once obtained, if the ammonia is reckoned as urea, from the decomposition of which it has without doubt arisen, and this amount is added to the residue found on weigh- Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 219 ing. Very satisfactory results may be obtained with the ap- paratus (fig. 17) constructed by me, which allows of the collec- tion and estimation of the disengaged ammonia. A is a water bath twelve centimeters high and eleven centi- meters broad, with a tin tube of two and a half or three centi- meters in diameter passing through its centre. A glass tube, BB, of the shape represented in the figure, can be readily pushed through this tin tube, and the porcelain dish seven or eight centimeters long and one and y^ broad, for holding the urine, is placed inside. The glass tube, BB, is connected at one end with the chloride of calcium tube, F, by means of a cork, while the portion drawn out and bent is connected by means of a doubly perforated cork with the little flask D, in which stan- dard sulphurii3 acid is placed. The drawn-out arm of the tube BB reaches nearly to the bottom of the flask. The flask D is connected with the aspirator E through the second perforation of the cork. The estimation is now readily made. The porcelain dish is first about three-quarters filled with not too small glass splin- ters, it is dried at 100" C, and then accurately weighed in a glass tube which can be closed with a cork covered with tin foil. Then exactly two cc. of urine are allowed to run from a pipette, which best holds just this amount, on to the pieces of glass in the porcelain dish, and it is carefully pushed into the tube BB, which is already connected with the little flask D, in which there are ten cc. of standard sulphuric acid, and the lat- ter is connected with the aspirator. Then the glass tube is carefully pushed through the tin tube of the water bath, and the second opening is closed with the chloride of calcium tube F, by holding the glass tube firmly with the left hand and tightly securing the cork in with the right. When the water in A is heated to boiling, the cock of the aspirator is opened, having first found that the apparatus is air-tight, and the water allowed to flow out in such quantity that the air dried in F shall pass through the sulphuric acid in D in bubbles which follow each other every second. The urine is evaporated in this manner at 100° C. in a stream of dry air. In three-quarters of an hour this operation is finished, but the residue of the urine persis- tently retains the water, and must, therefore, be kept at the same temperature for some time longer. If illuminating gas is at the \ Digitized by Microsoft® 220 ANALYSIS OF TEE UBINE. disposal of the experimenter, a stream of dry gas many suitably replace the stream of air, and may finally be conducted to the lamp under A and burned. The aspirator is thus rendered su- perfluous. The pieces of glass facilitate exsiccation very much, so that in about three hours the entire operation may be re- garded as completed. The gas or air stream is now inter- rupted, the chloride of calcium tube removed, the tube re- moved from the water bath, and the little porcelain dish introduced into the tube in which it was weighed before the evaporation, which tube is then immediately tightly closed with the cork. After complete cooling in the desiccator the tube is weighed ; the increase of weight gives the amount of urinary residue found in two cc. of urine. Next the ammonia evolved must be estimated. First the carbonate of ammonium which is usually found sublimed in the evaporating tube is Washed into the flask, then the cork is removed, and the bent arm is also washed with water from a wash bottle, one or two drops of tincture of litmus or cyanine solution are added, the fluid is heated to boiling to drive out all carbonic acid, and the unsatu- rated acid titrated with sodic hydrate. It is well to calculate the sodic hydrate immediately as urea ; the number of cc. now used, less than the number required to saturate the original acid, directly gives the amount of urea decomposed, which added to the weighed residue yields the whole amount of solid constituents of the urine. The standard sulphuric acid used in this estimation should contain 2 "667 grams of sulphuric acid in the liter, so that 1 cc. of it shall be saturated by 0'0011335 grams of ammonia, cor- responding to 0-002 gram of urea. If, then, to such sulphuric acid sodic hydrate is added of such a strength that 1 cc. of the former requires just 2 cc. of the latter for its exact saturation, each cc. of the sodic hydrate, less than 20, required to saturate the 10 cc. of sulphuric acid, exactly corresponds to 1 milligram of urea. Example : Two cc. of urine yielded 0-10 grams of solid residue in the little dish. The ten cc. of sulphuric acid required sixteen cc. of sodic hydrate after the experiment was ended ; there were, therefore, four cc. neutralized by the ammonia evolved, and these correspond to Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 221 0-004 grams of urea. Two cc. of urine then contained 0"104 grams of residue, and one thousand parts 52 -0 grams. 3. The whole amount of the solid constituents of the urine can be approximately reckoned from the specific gravity when determined with accuracy and with exact observation of the temperature. This is a fact which I have convinced myself of by a series of determinations. (See Analytical Experiments.) If the three last figures of the specific gravity carried out to four decimals is multiplied by the number "233, the product gives approximately the amount of solid matters in 1,000 cc. of urine. Example : The amount of urine in twenty-four hours =1 "500 cc. The specific gravity " " =1-0134: The amount of solid matters in 1,000 cc. =(0-233 x 134) =31 -32 grams. The amount in 1,500 cc. therefore = 46-83 grams, while by weighing, according to method 3, 46 -59 were found. The table given in the analytical appendix shows how large the error may be in this method. § 60. Estimation op the Non- Volatile Salts. To determine the total non-volatile salts contained in the urine, a measured quantity of urine is evaporated to dryness and ignited until all of the carbon is consumed. Yet this sim- ple method is subject to several sources of error, for at too high a temperature some of the chlorides present volatilize, and at a red heat the separated carbon may reduce the sulphates and phosphates, changing the former into sulphides and de- veloping phosphorus fumes from the latter. Besides, complete ignition of the charcoal requires a long time, since enclosed by the large amount of chlorides which are readily fusible, it is protected from contact with the air. All of the above sources of error may be reduced to a minimum by the following method when carried out with care. Ten cc. of urine first filtered are placed in a small weighed platinum dish with a well-fitting cover and evaporated to dry- ness on the water bath. The dish is then placed on a platinum Digitized by Microsoft® 222 ANALYSIS OF THE URINE. triangle and carefully heated witli as little fire as possible until the organic matters are carbonized, and no more gas is evolved from the swollen mass. After cooling, the contents of the dish are covered with boiling water, it is allowed to stand a short time, and the colorless feebly alkaline fluid is filtered through the smallest possible filter, the weight of whose ash is known. The carbonized residue is freed from all soluble salts by re- peatedly washing it with hot water, the filter is then washed and finally dried in the same platinum dish on a water bath. The platinum dish and its contents are then heated to a low red heat, and the carbonized residue and the filter are thus easily and completely consumed. The platinum dish, when the residue is free from all carbon, is put back on the water bath, the fluid obtained by extracting the first carbon residue is added and evaporated to dryness. The salts obtained are last of all heated to a low red heat before weighing, but the saline residue must first be dried a long time, since otherwise a loss may readily occur by decrepitation. For the same reason the dish must be kept well covered during the ignition and the temperature only raised to a dull red in order that no chlorides shall volatilize. If the dish is finally cooled over sulphuric acid, weighed, and the weight of the dish and filter ash subtracted from the gross weight, the remainder is the total amount of the non-volatile salts contained in ten cc. of urine. Example : The amount of urine = 1,500 cc. The platinum dish with cover and ash of 10 cc. = 14*343 grams. The platinum dish alone = 14*120 " 0*123 " Filter ash = 0*001 Non-volatile salts in 10 cc. of urine = 0*122 10 : 0*122 = 1,500 :x. x = 18*3 grams. § 61. Estimation of the Coloeing Mattees. A. The Color Table. (See Plate IV.) Vogel has succeeded by a large number of observations in establishing the color scales, given below, for the different Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 223 shades of healthy and pathological urine. These he has imi- tated artificially by mixing different amounts of gamboge, car- mine lake, and Prussian blue. He distinguishes three groups or shades. /. Oroup. Yellow Urines. The color is a yellow (gamboge) more or less diluted with water. The group has three shades of color whose starting point is the rarely occurring colorless urine. 1. Pale yellow (gamboge with much water). 2. Light yellow (gamboge with little water). 3. Tellow (gamboge with very little water). II. Orowp. Reddish Urines. Bed is more or less mingled with yellow (gamboge with car- mine lake). The urines of this group are designated by the adjective "high-colored." Three shades of color belong here also : 4. Reddish yellow. A little red is mingled with the yellow, but the latter is more prominent. (Gamboge with a little car- mine lake.) 5. Yellowish red. The red color together with the yellow is more distinct. (Gamboge with a little more carmine lake.) 6. Red. The red predominates, yet there is still some yellow mixed with it. (Carmine lake with a little gamboge.) III. Group. Brown (dark) Urines. The red color passes through brown almost into black. (Gamboge and carmine lake with more or less Prussian blue.) 7. Brown red. A little brown is mingled with the red. 8. Bed brown. More brown than the above. 9. Brownish black. Almost black, yet with a tinge of brown- ish red. The practised eye can still distinguish intermediate shades between these, when it can be said : the color is between light yellow and yellow ; it approaches nearer to the reddish yellow than the yellowish red, etc., but according to Vogel these nine shades suffice. B. Value of these Color Scales. The shades of color correspond to certain relative amounts of coloring matter. It has been Digitized by Microsoft® 224 ANALYSIS OF TEE URINE. found that by diluting a higher number with water all the lower numbers can be produced. All nine shades of color are in the same series, so that the color of urines may be regarded as dif- ferent dilutions of one and the same coloring matter. But we must naturally leave out of question the accidental colors, which rarely occur, due to the presence of bile, medicinal or food pigments, etc. These experiments carried out quantitatively prove that a urine diluted with an equal volume of water pro- duces nearly the next lower shade : 200 cc. of urine of a yellow- ish-red color diluted with 200 cc. of water becomes reddish yellow, and so forth. These relations are about the same for all parts of the scale, from which it follows that they may serve to determine the relative amount of coloring matter in different urines. The following table serves for such quantitative estimations : I. I II. I III. I IV. I V. I VI. I vn.|vin.|ix. | 2 4 8 16 32 64 128 256 1 2 4 8 16 32 64 128 1 2 4 8 16 32 64 1 2 4 8 16 32 1 2 4 8 16 1 2 1 4 2 1 8 4 2 1 pale yellow light yellow yellow reddish yellow yellowish red red brownish red reddish brown = 1. = 11. = 111. = IV. = V. = VI. = VII. = VIII. brownish black = IX. 0. Application of tJie Method. This table which has been drawn up serves us for the quantitative comparison of the amounts of urinary coloring matter eliminated ; it shows how much coloring matter equal parts of urine of different colors contain relatively. If a certain volume of pale-yellow urine contains one part of coloring matter, the same volume of yel- lowish red contains sixteen parts, of red thirty-two parts, of brownish black two hundred and fifty-six parts, etc. It further shows that one volume of yellow urine contains just as much coloring matter as four volumes of pale yellow, one volume of red as much as four volumes of reddish yellow, or thirty-two volumes of pale yellow, etc. If, therefore, one person passes 1,000 cc. of yellow urine in twenty-four hours, and another in the same time 4,000 cc. of pale yellow, both secrete an equal amount of coloring matter. Now, in order to make an approximate comparison by figures Digitized by Microsoft® qUANTITAIIVE ESTIMATIONS. 225 possible, Vogel places the quantity of coloring matter which 1,000 cc. of pale yellow urine contains = 1. But in order to obtain harmonious results by comparing the color of the urine with the color table, the urine must in the first place be perfectly clear ; in most cases, therefore, it must be filtered, and in the second place it must be examined by transmitted light in a layer four or five inches thick. There- fore, glasses four or fire inches in diameter are used which can hold 800 or 1,000 cc, since the color in thinner layers will ap- pear too light when compared with the table. Example : 1,800 cc. of urine having a yellow color are passed. 1,000 cc. pale yellow = 1 part coloring matter ; but yellow, ac- cording to the table, contains four times as much ; therefore, we have the following proportion : 1,000 :4 = 1,800 -.x =1-% as the amount of coloring matter in 1,800 cc. of yellow urine, the coloring matter in 1,000 cc. of pale yellow urine being considered as the unit. QUAJSTTITATIVE ESTIMATIONS OP INDIVIDUAL SUBSTANCES. § 62. VoLUMETKic Analysis. The use of this method renders urinary analysis simpler and its performance more rapid. In determining the weight of a body by titration, we do not do it by weighing the compound precipitated by any reagent, but we ascertain the amount of the solution of a reagent necessary to complete a certain re- action, and from this reckon the quantity of the material which was present. These determinations, which are always carried out by measuring the solution of the reagent used, are success- ful, however, only under certain conditiona, on which alone their accuracy depends ; these are the following : 1. The strength of the solution of the reagent must be most accurately known, and the amount of the standard solutions used must be capable of exact determination. 2. The end of the reaction, that is, the point at which just enough of the standard solution has been added, must be recog- nized in a distinct and striking manner. 3. The decomposition, on the accomplishment of which the analysis depends, must always remain the same. 15 Digitized by Microsoft® 226 ANALYSIS OF TEE URINE. 4 The decomposition must be so managed that none of the active or reactive agent is lost. General rules for attaining these conditions cannot be given well, since they differ with each substance, and must be treated more in detail in speaking of each one separately. Yet, before I pass to the individual methods, it is necessary to speak of the apparatus required, as well as generalities in their execution. k § 63. I. Apparatus. On account of the superiority of the French system of weights Fig. 18. ^^^ measures, these only are employed in quan- titative chemical determinations. It is well known that there is here an intimate connec- tion between volume and weight, so that 1,000 cc. of water at its greatest density, that is, at 15 cc II +4° C, = 1 liter, which weighs exactly one kil- ogram or 1,000 grams ; a cubic centimeter, there- j^jpj. fore, corresponds exactly to one gram. The measuring vessels in which volumetric analyses are performed are all divided into cubic centimeters (cc.) ; of these may be men- tioned : 1. The Graduated Pipette. This is the glass apparatus whose form is shown in fig. 18, a and 6; it is used in measuring off the necessary fluids, and, therefore, has a mark on its neck up to which it contains just 50, 20, 15, 10, 4, f' 3, and 2 cc. In measuring, the end of the pipette is dipped into the fluid, which is sucked up until it has risen above the mark in the neck ; the opening above is then closed by the finger slightly moistened (neither wholly dry nor yet ^ f J_ wet), the pipette is freed from fluid adhering to V the outside by wiping, and the solution is allowed - to flow from the pipette by slightly lifting the finger, until it stands exactly at a level with the mark ; this point is determined by holding the surface of the fluid on a level with the eye. Having reached this point the pipette is tightly closed with the Digitized by Microsoft® I QUANTITATIVE ESTIMATIONS. 227 Pig. 19. HI =-s Fig. 30. Pt^, finger again, and the contents may be allowed to flow into any vessel at pleasure. It must be observed, however, how the pipette has been graduated, whether the last drop, which col- lects at the lower end after a time and which may be removed by blowing it out, must be taken or not. The most accurate and most suitable are the "pipettes a I'ecoulement," which are so graduated that they allow the designated amount of fluid to flow out directly in a stream, so that the drop which remains adherent to the lower' end need not be blown out. It is pre- ferable in all cases to place the point of the pipette on the moistened side of the glass, while it is being emptied. This method of measuring gives the most constant results ; it is self-evident, however, that the pipettes must be graduated according to this method of reading off'. For urinary analysis pi- pettes of 50, 30, 20, 15, 10, 3, and 2 cc. are necessary for a com- plete outfit. The following ap- paratus serves for measuring standard solutions. 2. Mohr's Pipette. These pipettes are graduated through- out their entire length, and hold 30 or 40 cc, each of which is again di- vided into ten parts (that is, into ^g- cc). (Fig. 19.) They are not drawn out at the top, so that fluids may be easily poured into them, and the opening may then be closed with a cork. The following very simple contrivance, and one which at the same time answers all requirements, allows the standard Fig. 31. Digitized by Microsoft® 228 ANALYSIS OF TEE USmE. solutions to flow out drop by drop. A short piece of Tulcanized rubber tubing, fig. 20, oa, which is pressed together by a wire clamp bh, fig. 21, by which it is hermetically closed, but can be more or less opened by pressure applied to the two plates c, c, has a small glass tube, d, ending in a fine point, introduced into its lower end. This rubber tube is drawn over the small end, b, of the pipette, represented in fig. 19, which is then fastened in a wooden stand so that it is perfectly vertical. Fig. 22 shows the entire apparatus. When ready for use the pipette is filled to the 0-point with the standard solution, the urine to be tested is measured off, and the standard solution is allowed to flow, at last drop by drop, pj^ 33 by opening the wire clamp until the right point is ex- actly reached. By means of this ingenious contriv- ance we not only obtain a Fig, 32. more rapid flow, but also a surer discharge of the single drops. In a series of investigations which extend over a long time it is well to have two or more such pipettes on a stand, so that Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 229 they may be left standing wholly or partly filled, if the upper opening is closed with a stopper, without danger of evapora- tion. Fig. 23 shows a similar arrangement which might be very useful, to physicians, and is sufficiently intelligible without an explanation, ab, on which the eight arms are fastened, is a brass case which rests .on a clamp, and which can be readily turned on its axis. The pipettes are held above by a screw clamp, while below they simply rest on the holder, which is turned out conically and has a hinge, so that the pipettes can be readily taken out. c, c, c are pieces of cardboard which are fastened by a small clamp to each arm, and on which the nature of the fluid in the pipette is recorded. Finally, c? is a level resting on four screws to keep the whole apparatus perpendicu- lar. It is self-evident that by constructing the apparatus some- what larger six or eight pipettes may be held by it. The same purpose is served by 3. The Graduated Burette. The ordinary form of this ingeni- ous apparatus is pictured in fig. 24. The narrow pj^ 34 tube serves for pouring the fluid out, and must, f:3r therefore, be placed somewhat lower than the open- ing of the broad tube, so that the fluid can be con- ®"S^ veniently removed. These burettes either hold [ 30 cc. and are then divided into tenths like the pipettes in fig. 19, or they contain 50 cc. and are then divided into 100 degrees, each one of which | marks half a cc. When used they are filled to A M above the 0-point with the standard solution, and ' then the excess is poured out of the narrow tube , t 2 exactly to the 0. Mohr's apparatus described above renders these easily perishable instruments rather superfluous. The Mohr pipette and the burette , "^ must each be graduated d Vecouhment. 4. The Graduated Cylinder. This is used for pre- l| paring the standard solutions, and is represented in fig. 25. Such a cylinder must contain 500 or 600 cc. and have a division line for every 5 cc. The 1 so-called measuring flasks serve the same purpose, fig. 26; they are filled to a mark in the neck, and ^i hold exactly one, one-half, or one-quarter of a liter. These Digitized by Microsoft® ^ 230 ANALYSIS OF THE UBINE. flasks are preferable to tlie cylinder in the preparation of stan- dard solutions.* § 64 II. Peefoemance. In carrying out the volumetric method, as already remarked above, we must pay the greatest attention to the necessary standard solutions, since the correctness of the results ob- tained depends solely on the accuracy of these. Special direc- tions will be given with each method, and we must remark at the same time, that such normal solutions must always be only prepared and used at medium temperatures, since their volume would be considerably changed by heat. Furthermore, certain Fig. 26. precautions are to be observed in reading off the level of the fluid in the gra- duates, which precautions must be accu- rately followed in carrying out the methods : 1. Care must \ be taken that no bubbles render the height of the ' fluid uncertain ; they must, therefore, be removed either by waiting or by being broken up by a glass rod. 2. The surface of the fluid must be level"; this is attained in pipettes by allowing them to hang freely, but in burettes best when they are placed against a window pane. 3. If any sort of fluid is poured into a narrow tube, it is ob- served that its surface forms a curve as the result of capillarity ; if this curve is carefully examined, best by transmitted light, * The meclianician Niemann, in Alfeld near Hanover, Germany, furnishes the above pieces of apparatus of great excellence and at low prices. Digitized by Microsoft® , QUANTITATIVE ESTIMATIONS. 231 several zones may be readily distinguished in it (Fig. 27.) Now in reading off it is not immaterial whether sometimes the upper and sometimes the lower edge or the middle of the curve coincides with the division line of the tube. The mea- surements are made most accurately when the eye is placed on a level with the lower edge of the dark zone, fig. 27, after the pipette or burette has been brought to the perpendicular, and the division line of the tube is read off from this ; this edge can be most sharply brought out and ob- served by transmitted light. If the urine to be tested has been measured in this manner, and the pipette or burette has been filled with the standard solution, the latter is al- lowed to flow into the urine drop by drop until the end reaction distinctly appears. If this end re- action is very apparent through the whole fluid, it shows a great excellence of the method; but if this is not the case, the mixture must be frequently tested toward the end of the experiment until the right point has been finally reached. Each method, moreover, has its own reaction, which must be spoken of separately. If the standard solution has been added up to this point, the volume used is read off with the observance of the above precautions, and the amount of the substance to be determined is reckoned from it. For example : If, in estimating the amount of urea in 10 cc. of urine, 20 cc. of the mercury solution have been used, each cc. of which exactly corresponds to 10 milligrams of urea, there are con- sequently in those 10 cc. of urine (20 x 10) 300 milligrams of urea ; in 1,000 cc. then 20-00 grams. Lastly, we must observe, in using a burette (fig. 24) care must be taken not to spill the fluid out of the wide tube, by inclin- ing it too much. This may readily happen, if a drop remains hanging in the narrow delivery tube and hinders the penetra- tion of the column of fluid ; this disturbing element, however, may be easily removed by blowing into the tube. The amount of urea, chlorine, phosphoric acid, free acids, sulphuric acid, lime, ammonia, and sugar ia the urine may be determined volumetricaUy. Digitized by Microsoft® 232 ANALT8IB OF THE UBINE. § 65. Estimation of Urea by Liebig's Method. A. Principle. If a dilute solution of mercuric nitrate is added to a dilute solution of urea, and if tlie free acid of the mixture is neutralized from time to time with carbonate of sodium, a flocculent, bulky, white precipitate is obtained, which is insoluble in water. If the solution of mercury and carbonate of sodium are added alternately as long as this precipitate is formed, a point occurs at which the mixture assumes a yellow color, due to the formation of mercuric hydrate or a basic salt from the ad- dition of the carbonate of sodium. If now the fluid is filtered, it contains no determinable amount of urea ; all of the urea is precipitated in combination with mercuric oxide. The precipi- tate which takes place contains to one equivalent of urea four equivalents of mercuric oxide. The above-mentioned yellow color with carbonate of sodium will not begin until a volume of the mercuric solution, in which there are seventy-seven parts of oxide, has been added to ten parts of urea in the solu- tion of urea, that is, four equivalents to one equivalent of urea. If no more mercuric solution is added to the solution of urea than is necessary for a complete precipitation, the mixture tested with carbonate of sodium still remains white ; but if it is now allowed to stand a few hours the character of the precipitate changes, it becomes crystalline, and the supernatant fluid then gives a yellow precipitate with alkalies. In the acid solution on long standing the compound with four equivalents of mer- curic oxide is reduced to a compound which contains a less amount, that is, a part of the mercuric oxide enters into solu- tion again. In order now to reach the point at which all of the urea is precipitated, and to determine whether the necessary amount of the mercuric solution has been added to form the compound with four equivalents of mercuric oxide, it is necessary to neu- tralize with carbonate of sodium. If a drop of the mixture added to a drop of a solution of carbonate of sodium in a watch glass remains white, free urea is still present in the fluid : if, when the two drops flow together, a yellow pellicle appears on the surface, the limit is reached, or, more accurately, is a little exceeded. To bring out this end reaction, only a very slight excess of mercuric oxide is necessary. Digitized by Microsoft® Q UANTITA TIVE E8TIMA TWITS. 333 If we know tlie amount of oxide whicli our mercuric solution contains, and if we further determine the volume which must be added to a solution of urea of unknown strength until the latter is completely precipitated (until on neutralizing a drop of the mixture with carbonate of sodium a yellow color appears), the amount of urea in the solution can be reckoned. Or, on the other hand, if a certain volume of the mercury solution has been required to precipitate a known amount of urea, for ex- ample, 100 mgrm., the same volume of the mercury solution will indicate the same amount of urea, 100 mgrm., in solutions containing unknown amounts. B. Preparation of the Necessary Solutions. 1. Urea Solution of Known Strength. Four grams of pure urea, dried at 100° C, are dissolved in water and diluted until the volume of fluid amounts to exactly 200 cc. 10 cc. of this solution contain exactly 200 mgrm. of urea. 2. Solution of Mercuric Nitrate. The solution of mercury which serves to determine the urea in urine must be of such a strength that 20 cc. of it Just suffice to completely precipitate the urea in 10 cc. of solution 1 (in which there are 200 mgrm. of urea). 1 cc. of the mercury solution should correspond to 10 mgrm. of urea, and for this purpose it must in the first place contain a quantity of oxide sufficient to form with 200 mgrm. of urea the compound with four equivalents of mercuric oxide, and also a slight excess which serves to indicate the complete precipita- tion of the urea, so that after adding the last drop of the 20 cc. to 10 cc. of the solution of urea a distinct yellow color is evi- dent, when a few drops of the mixture are treated with carbo- nate of sodium on a watch glass. Liebig has found that to 100 mgrm. of urea, which according to the calculation require 720 mgrm. of mercuric oxide, 10 cc. of the mercury solution must contain 772 mgrm. of oxide to produce in dilute fluids the reaction of mercuric oxide with carbonate of sodium distinctly. Each cc. of the solution must, therefore, contain an excess of 5 '2 mgrm. of mercuric oxide; and a liter 77*2 grm. of oxide in all, or 71 "48 grm. of metallic mercury. a. Preparation from Pure Mercury. 71 '48 grm. of chemically pure mercury are weighed off, placed in a beaker and dissolved in pure nitric acid. When solution Digitized by Microsoft® 234 ANALYSIS OF THE URINE. has resulted, it is warmed and nitric acid frequently added until no more traces of nitrous vapors are seen to escape, in other words, until the mercurous oxide is completely trans- formed into mercuric oxide, and it is then evaporated in the same vessel to a thick syrup. The mercuric nitrate thus ob- tained is then diluted with water to exactly a liter ; if a basic salt separates, it is allowed to settle, the clear fluid is carefully poured off, and the precipitate is dissolved again by a few drops of nitric acid. The accuracy of the solution thus obtained must now be tested in the manner described below. b. Preparation from Mercuric Oxide. It is best to prepare the mercury solution from pure mercuric oxide ; it can also be readily prepared in a porcelain dish by heating mercurous nitrate, which has been recrystallized several times. There occurs in commerce a mercuric oxide sufficiently pure for this purpose, for when it leaves no visible residue when heated on platinum foil, it is quite suitable. 77"2 grm. of such mercuric oxide which has been dried at 100° C. are accu- rately weighed, dissolved in as little nitric acid as possible in a porcelain dish at a gentle heat, evaporated to a syrupy consis- tency and then diluted to one liter. If a basic salt should sep- arate, nitric acid is added drop by drop until the precipitate just disappears. According to Dragendorff, yellow mercuric oxide is precipi- tated from a solution of 96'855 grm. of pure corrosive sublimate by dilute sodic hydrate ; it is first washed by decantation and then on a filter. This precipitate is afterward dissolved in a sufficient amount of nitric acid and diluted to nearly a liter. The exact strength of the solution is fixed by titrating with the normal solution of urea as given under d. c. Preparation from Mercurous Nitrate. If no chemically pure mercury or mercuric oxide can be obtained, crystalline mercurous nitrate must be procured, and this converted into mercuric oxide by heating with nitric acid. d. To Standardize the Prepared Mercury Solution. Exactly 10 cc. of the solution of urea, 1, are measured off with a pipette, poured into a small beaker, and then the ap- proximately dilute mercury solution is added drop by drop, until a few drops of the mixture neutralized with carbonate of sodium on a watch glass give a distinct yellow color. Digitized by Microsoft® qUANTITATIVB ESTIMATIONS. 235 If, for example, 19'25 cc. of the mercury solution have been required" to produce tlie end reaction, 7'5 cc. of water are added to each 192-5 cc, and thus 200 cc. of solution are obtained, of which 20 cc. wiU exactly precipitate the urea from 10 cc. of the urea solution. Its accuracy is confirmed by a second test : if the yellow color appears distinctly after adding 20 cc, the solu- tion may be used for determining the urea in urine. 3. Baryta Solution. This is obtained by mixing one volume of nitrate of barium solution and two volumes of caustic baryta, both solutions saturated in the cold. C. Performance. In order to be able to determine the urea in the urine by this method, the phosphoric acid must first be removed. Therefore 40 cc. of urine are measured ofi', with a pipette, treated with 20 cc. of the baryta solution, and the precipitate which occurs is separated by filtering through a dry filter. For each analysis 15 cc. of the filtrate are measured off, which, therefore, contain exactly 10 cc. of urine. In most cases one volume of the baryta solution to two volumes of urine is sufficient to remove all of the phosphoric and sulphuric acids, so that some baryta still remains in the solution. But if the urine contains alkaline car- bonates, which under certain circumstances may consist of car- bonate of ammonium from the decomposed urea, or if it has a very strongly acid reaction, one volume of baryta solution to two volumes of urine are often not sufficient; then more must be taken. If three volumes of baryta solution are mixed with four volumes of urine, 17*5 cc. of the filtrate are taken (corresponding to 10 cc of urine) ; with equal volumes of baryta solution and uriae 20 cc. are taken for the analysis, etc. The standard mercury solution is allowed to flow from a Mohr pipette into this measured amount of urine without previ- ously neutralizing and with constant stirring, and when no more precipitation is observed and the mixture no longer thickens, the test is performed. For this purpose a few drops of the mixture are placed on a watch glass by means of a glass rod, and a few drops of carbonate of sodium solution are allowed to flow on to it from the edge of the watch glass ; a Mohr's india-rubber pipette is good for this purpose. If the mixture retains its white color after some seconds, there is still some free urea present, and a few more drops of the mercury solution are added and it is Digitized by Microsoft® 236 ANALYSIS OF THE UBINE. again tested ; this process is repeated until at a new trial on the watch glass a distinct yellow color results after the carbo- nate of sodium solution has been added. The shade must natu- rally be the same as that at which the mercury solution was originally standardized, for by sometimes adding the solution until a weak and sometimes until a strong yellow color is pro- duced, an error is caused, which with a little experience can be avoided. The amount of urea is then reckoned from the number of cc. of the mercury solution which have been used, but under cer- tain circumstances a few corrections are to be made which are mentioned below. D. Modification of the Process and Corrections Required by Dif- ferent Circumstances. 1. The Urine contains more than 2 per cent, of Urea. Our mercury solution is standardized by a urea solution which contained 2 per cent, of urea; we need, therefore, for the complete precipitation of the urea in 15 cc. of our urea solution, and for producing the end reaction with carbonate of sodium, 30 cc. of mercury solution. The mixture, therefore, will amount to 45 cc, and we have in it 30 x 5'2 = 156 mgrm. of free mercuric oxide ; each cc. contains, therefore, 3 "47 mgrm. If the 15 cc. of the urea solntion contain 4 per cent, of urea, and if to 15 cc. of the same 60 cc. of mercury solution are added, there are together 75 cc. of mixture, in which there are 60 x 5*2 = 312 mgrm. of free mercuric oxide, in each cc, therefore, 416 mgrm., and consequently 0'69 mgrm. more oxide than is neces- sary to produce the end reaction with carbonate of sodium. It has thus happened that in a urinary analysis an error is made when the amount of urea is more than 2 per cent., so that the true amount of urea is diminished. If the urine contains, as in the above case, 4 per cent, of urea, 60 cc. of the mercury solution would not be necessary, but only 59-37 cc This error is avoided by adding, when 15 cc. of urine are taken, for the number of cc. of mercury solution more than 30 cc. which are used, half this number of cc of water to the mix- ture before testing with carbonate of sodium. If, for example, 50 cc. of mercuric solution are used to 15 cc. of urine, that is, 20 cc. more than 30, then 10 cc. of water must be added before testing with carbonate of sodium. Digitized by Microsoft® qUANTITATIYE ESTIMATIONS. 337 2. The Urine contains less than 2 per cent of Urea. For the same reasons which are given above, when the urea in the urine only amounts to 1 per cent., to obtain the end reaction there will be required for 15 cc. of urine, not 15 cc. of the mercury solution, but 15-3 cc. Through this error the amount of urea is found to be increased, and in order to obvi- ate it when the urine is dilute, for every 5 cc. of the mercury solution less than 30 cc. which are used, O'l cc. must be sub- tracted from the number of the cc. of mercury solution used. If to 15 cc. of urine 25 cc. of mercury solution are used, that is, 5 less than 30 cc, for these 5 cc. 0-1 cc. is subtracted and the calculation made for only 24-9 cc. of the mercury solution. 3. The Urine, contains Chloride of Sodium. When the amount of chloride of sodium reaches 1 or 1| per cent., it exercises an influence on the determination of urea with mercuric nitrate. If, for instance, to 10 cc. of our urea solution are added 20 cc. of the mercuric solution, a distinct reaction for mercury with carbonate of sodium is obtained at the end, but this reaction fails when we add 100 to 200 mgrms. of chloride of sodium to the solution of urea, and in order to make it appear now we must add IJ or 2| cc. more of the mercury solution. The determination of the urea comes out 15 or 25 mgrm. too high, therefore. The same is the case with the urine also if it contains 1 or IJ per cent, of chloride of sodium. The formation of corrosive sublimate is the cause of this. Mercuric nitrate and chloride of sodium mutually decompose each other, as is well known, into corrosive gublimate and nitrate of sodium, but corrosive sublimate does not precipitate a feebly acid solution of urea, and therefore remains in solution. This is naturally the case also in the determination of urea in the urine ; the excess of mercuric oxide which should give the yellow color on the addition of carbonate of sodium is not now, however, in the form of a nitrate, but of corrosive sublimate to- gether with free nitric acid. If we now add carbonate of sodium to this mixture bicarbonate of sodium is formed by the free nitric acid, and this does not precipitate the corrosive sublimate, therefore the reaction does not occur, and we must add some more mercuric nitrate in order to obtain it. If the mixture contains a larger amount of chloride of sodium than 1 or IJ per cent., the amount of corrosive sublimate formed increases with Digitized by Microsoft® 238 ANALYSIS OF THE URINE. it, but by the addition of carbonate of sodium tlie carbonic acid which is freed is no longer sufficient to prevent the preci- pitation of the mercuric oxide ; there results, therefore, now a brownish-yellow precipitate. According to Liebig this is the reason why the indication of the complete precipitation of urea in the presence of a certain quantity of chloride of sodium (1 or Ij per cent.) is deferred, and the limit of the reaction does not extend, if the amount of chloride of sodium increases still more. If a urine, therefore, contains from 1 to \\ per cent, of chlo- ride of sodium, to obtain the right number of milligrams of urea in 10 cc. of urine two must be subtracted from the whole number of cc. of the mercury solution used, and the remainder only reckoned for urea ; the results obtained are then more accurate and comparable. If it is necessary to know the absolute quantity of urea in the urine, the chlorine must first be removed by a solution of nitrate of silver, 1 cc. of which exactly corresponds to 10 mgrm. of chloride of sodium. This solution of silver is obtained by dissolving 29 '075 grm. of fused nitrate of silver in water and diluting the solution to a liter. 1 cc. corresponds to 10 mgrm. of chloride of sodium ; it is the same silver solution which is used for determining the chlorine according to Mohr's method, § 66, B, 1. The method of performing it is as follows : The amount of chloride of sodium in 10 cc. of the original urine is determined by means of the silver solution according to § 66. If, for example, we have used 17'5 cc, the presence of 175 mgrm. of chloride of sodium is indicated. We now measure off with a pipette 30 cc. of the mixture of baryta and urine, render the reaction feebly though distinctly acid by a few drops of nitric acid and treat this with 2 x 17*5 cc. = 35 cc. of the silver solution. The whole volume of the mixture amounts to 65 cc; the precipitated chloride of silver is filtered off and half the mixed fluid, that is, 32'5 cc, in which there are 10 cc. of urine, is taken from the filtrate. The urea is now determined in this amount as is usual by the standard solution of mercury, in which, however, the dilu- tion resulting from the addition of the silver solution must be taken into account. (D, 2.) If the 32 '5 cc. of the urine mixture taken for the titration of Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 239 the urea contained 2 per cent, of urea, 65 cc. of the mercury solution would be required. But if only 25 cc. were required, then according to D, 2, for (65 - 25) 40 cc. 0-8 cc. must be sub- tracted. Accordingly the urea must be calculated for only 24-2 cc. RavMiberg's Method.* Two specimens of 15 cc. each of the urine mixture are measured off. One is feebly acidulated with nitric acid, and the mercury solution, which serves for determining the urea, is allowed to flow into it until a permanent cloudiness appears. The number of cc. of the mercury solution used up to this point forms the correction for the chloride of sodium, and is taken into account in subtraction. (See § 13, C, 3.) The se6ond specimen is used for precipitating the urea. The mer- cury solution is allowed to gradually flow in without previously acidifying, and the mixture is kept neutral by successive addi- tions of pure precipitated calcic carbonate. In order to deter- mine whether all of the urea is precipitated, a large drop of the mixture is placed by means of a glass rod on a clean glass plate covered thickly on its under side with asphaltum varnish, and it is covered with a drop of bicarbonate of sodium stirred up with water ; the appearance of the first distinct traces of a yel- low color indicates the end of the reaction. By using the bicarbonate of sodium the disturbing influence of the corrosive sublimate which is formed is entirely obviated, so that the urine can be accurately titrated up to one or two mgrm. of urea. The bicarbonate, however, must contain no normal carbonate, and must, therefore, before using be washed with small amounts of water after being rubbed up finely, until it no longer browns turmeric paper. 4. The Urine contains Albumen. If the urine contains albumen, the urea cannot be directly determined by the method given, but the albumen must first be removed. The usual procedure, therefore, suffers the fol- lowing modification : 100 to 200 cc. of urine are heated in a closed vessel on a water bath, until a complete coagulation of the albumen has taken place and thick flocculi have separated, so that the urine appears clear. If the coarse flocculent precipitate does *Aimalen d. Chem. u. Pliami., Band 133, p. 55. Digitized by Microsoft® 240 ANALYSIS OF THE URINE. not form from lack of free acid, acetic acid is carefully added drop by drop to the hot fluid until it has taken place. Heating for half an hour is amply sufficient. Then after the fluid con- taining the coagulated albumen has become cold, it is filtered and the clear filtrate is used to estimate the urea, phosphoric acid, etc. 5. The Urine contains Carbonate of Ammonium. Since the carbonate of ammonium in urine comes from de- composed urea, it may be of interest under certain circumstances to estimate the amount of urea, which corresponds to the car- bonate of ammonium. Liebig found that foul ammoniacal urine, when decomposition had not gone too far, frequently gave the same results as fresh urine. If in such a urine a precipitate which contains two equivalents of mercuric oxide to one equiv- alent of ammonia occurs after the addition of mercuric nitrate, an equal amount of mercuric oxide is required for decomposed as well as for undecomposed urea, since the latter in its decom- position yields two equivalents of ammonia. (One equivalent of urea to four equivalents of mercuric oxide.) Investigations which were undertaken, however, showed that this relation did not remain constant, and that frequently more of the mercury solution was required. ' If, therefore, we wish for accurate re- sults, the ammonia and urea must be determined separately, and the former must be recalculated for urea. There are two ways to do this : a. One portion of the urine is precipitated with the baryta solution, a volume of the mixture corresponding to 10 cc. of urine is heated on the water bath until the ammonia is expelled, and the urea is then estimated as usual. In a second portion not treated with baryta solution the ammonia is determined volumetrically with a standard sulphuric acid solution, each cc. of which corresponds to 11-32 mgrm. of ammonia or 20 mgrm. of urea. (500 cc. of such an acid must contain 16"333 of mono- hydrated sulphuric acid.) b. A definite volume of the urine treated with baryta solution is distilled, and the ammonia which passes over is collected in a known volume of standard sulphuric acid. By means of a standard sodic hydrate, which is of corresponding strength to the sulphuric aciS, the rest of the acid is titrated back, and the number of cc. saturated by ammonia thus found is calcu- Digitized by Microsoft® qUANTITATIVE ESTIMATIONS. 241 lated for urea. One cc. of sulphuric acid corresponds to 20 mgrm. of urea. The results by this second method are more exact than by the first. Kletzinsky found by a series of comparative investigations that small amounts of other nitrogenous substances besides* urea were precipitated from the urine by mercuric nitrate, so that naturally the amount of urea fell a little too high. These unknown substances may be separated by precipitation with a solution of sugar of lead and their disturbing influence re- moved. On the average this error amounts to about two per cent., for Kletzinsky obtained as a mean of several urea estima- tions, which he performed once in the ordinary manner and again after previous precipitation with sugar of lead, 0.593 grm. of urea in 10 cc. of urine instead of 0'580 grm. This error is so small, that in ordinary urinary analysis the tedious pro- cess of precipitating the urine previously acidulated with acetic acid with a solution of sugar of lead may safely be omitted. These substances are also said to yield ammonia on boiling with sulphuric acid, and to have a disturbing influence on the urea determination by the method of Bagsky and Heintz.* If the urine contains sarkosin, as is the case after the internal use of this substance, the precipitation of the urea present at the same time is completely prevented, both in the neutral as well as in the alkaline solution. (E. Baumann and J. von Mer- iag.) t The same is true, according toE. Salkowski,i" of methyl- hydantoin, and according to Schultzen and Nencki of acetamid also. If a solution containing equal molecules of urea and sar- kosin or methylhydantoin is titrated, at first no precipitate occurs ; but if the titration is carried farther, the end reaction occurs far later than would be caused by the urea present; indeed, the latter appears to be present in double the amount that it really is. (E. Salkowski.) In these cases Liebig's method is wholly useless. Lastly, the fact should be remembered that allantoin also, like urea, is precipitated by mercuric nitrate. The method de- scribed above, therefore, will cause an error when allantoin ■occurs in the urine also. The error which is caused by the con- * Prager Vierteljahressolirift, 1855, ii. p. 88. f Berichte d. deutsch. chem. Gesellschaft, Band 8, p. 588 und 639. tibid. ^g Digitized by Microsoft® 242 ANALYSIS OF TEE UBINE. Fig. 38. stant presence of kreatinin in the urine, is more perceptible,' though always less, for, as I have found, this body is also pre- cipitated by mercuric nitrate. The daily quantity of kreatinin amounts to 0'8 to 1 grm. under normal circumstances. * The excellent methods for the quantitative determination of urea given by Heintz* and Eagsky,t as well as by Bunsen,:]: a,re not, however, entirely free from these and similar sources of error, and since they are considerably more detailed and de- mand more time than Liebig's method, they are employed in practice less frequently. Estimation of Urea ^y the Knop-Hufner Method.§ A. Principle. As was mentioned above under urea, § 2, t>, 7, hypobromite of so- dium decomposes urea into carbonic acid, nitrogen, and water. The carbonic acid is very quickly absorbed by the lye, so that the urea can be quantitatively de- termined by the direct measurement of the nitrogen. One grm. of urea yields 370 cc. of nitrogen measured at 0° C, and 760 mm. barometric pressure. B. Preparation of the Solution of Hypo- bromite of Sodium. 100 grm. of sodic hy- drate are dissolved in 250 cc. of water, and 25 cc. of bromine are added after the solution has become perfectly cold. 60 cc. of this solution, diluted with 200 cc. of water, are sufficient to develop 130 to 150 cc. of nitrogen from a chloride of ammonium solution. C. Performance. The decomposition of urea takes place very well in Huf- ner's apparatus, shown in fig. 28. A bellied vessel holding about 100 cc. is in solid connection with a small vessel, a, which holds at most from 5 to 8 cc, by *Poggend. Annal., Band 66, p. 114. f Amialen d. Chem. u. Pharm., Band 56, p. 39. J: Annalen d. Chem. u. Pharm., Band 65, p. 375. g Journ. f. pT. Chem., N. F., Band 3, p. 1. Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 243 means of a tolerably wide mouth of 1"5 cm. in diameter. Be- tween the two, at b, there is inserted a tightly-fitting glass stop- cock, with a bore 8 or 10 mm. wide. The upper, smaller end of the larger vessel, d, is tightly surrounded by the neck of a glass dish, k, which has a width of 1 dm. and a depth of 4 or 5 cm., and rises up into its centre about 1 cm. This end also ex- tends into the opening of a eudiometer, e, which stands over it. The eudiometer is about 30 cm. long, 2 cm. wide, and is di- vided into \ cc. The whole apparatus is properly attached to an iron stand,/,/. The operation is now carried out as follows: With the aid of a funnel having a long neck, the glass, a, together with the bore of the stop-cock, is filled with the urea solution, 2 or 3 cc. of urine being quite sufficient; 10 cc. of urine are diluted to 40 or 50 cc, and from 8 to 12 cc. of this dilute urine are used for each analysis. The cock is then closed, and a mixture of equal parts of lye and distilled water is poured into the larger vessel, c, up to the edge. In the dish, Tc, there is placed a layer of saturated chloride of sodium solution, or, better still, the same bromine lye, 2 cm. deep, which serves as a shutting-off fluid. During this time only a few air bub- bles are evolved from c ; when they have disappeared, the eudi- ometer filled with water is turned upside down over d, and, when it is fastened, the reaction may commence. The stop- cock, &, is now turned at once, and the two fluids are thus brought together suddenly. The heavy lye quickly sinks into the lower vessel and brings about decomposition of the urea with active evolution of nitrogen which collects in the eudiome- ter. If an accurate determination is not required, the ex- periment may be interrupted after five minutes ; in the other case it is advisable to wait a few hours. The eudiometer is then taken from the dish, h, its opening closed with the thumb, and it is carried to a cylinder filled with water and treated in measuring the gas according to Dumas's rule for the determina- tion of nitrogen. It is well to employ Knop's lye as fresh as possible. The calculation is carried out according to the following formula, since 1 grm. of urea yields 370 cc. of nitrogen at 0° C. and 760 mm. pressure : Digitized by Microsoft® 344 ANALYSIS OF THB URINE. 100 V {l-V) ^ ^ 760-370. a (1 + 0-003665 #°.) a = the volume of urine employed. V = the volume of gas read ofE. b = the height of the barometer. t = temperature. i'= the tension of aqueous vapor for the temperature t. Of the other constituents of the urine, uric acid and kreatih also give up a portion of their nitrogen; but with the small amounts of these substances which the urine contains the error caused by them is very small. Ivon* produced the decomposition in a simpler apparatus. It consists of a small glass tube 40 cm. high, which is divided into yV cc, and has a glass stop-cock at its upper part, above which there is a short piece of tubing of the same diameter, also divided. The apparatus is open at both ends. To determine the urea the lower end is sunk into a cylinder of mercury wide at the top ; then 2 or 3 cc. of urine are placed in the upper part, and by opening the stop-cock it is allowed to flow into the lower part ; it is afterward washed with a little sodic hydrate and the upper piece of tubing is filled with a solution of hypo- bromite of sodium. (Ivon uses the following solution: 30 grm. of sodic hydrate, 5 grm. of bromine, and 125 grm. of water.) If this is allowed to flow into the lower receiver by a quick but careful turning of the stop-cock, the development of gas begins immediately and is finished after five or six minutes. The ni- trogen is then measured as above, reduced for pressure and temperature, and calculated for urea. This method excels from its great simplicity, rapid per- formance, and sufficient accuracy. Bunsen's Method modified by G. BuNGE.t 50 cc. of urine are mixed with 25 cc. of an aramoniacal solu- tion of chloride of barium as concentrated as possible ; it is filtered through a dry filter, and 15 cc. of the filtrate, corre- sponding to 10 cc. of urine, are put into a strong glass tube sealed at the bottom, and containing about 3 grm. of solid, pure *Buletin de la Society chim. de Paris, 19, p. 3. f Zeitscliriftf. analyt. Chem., Band 13, p. 138. Digitized by Microsoft® QUANTITATIVB ESTIMATION'S. 345 cMoride of barium. In introducing the mixture of urine care must be taken to keep the walls above the fluid dry. The tube is then thoroughly sealed over a lamp an inch to an inch and a half above the fluid, and heated five or six hours to 200° 0. After it has cooled, the upper part of the tube is broken off, the contents thrown on a filter and thoroughly washed with water. The glass tube, on the inside of which small portions of carbonate of barium are frequently firmly adherent, is also thoroughly washed out, the whole amount of the carbonate of barium is dissolved in hydrochloric acid, filtered if necessary, and the barium precipitated by sulphuric acid as barium sul- phate. After a time the sulphate of barium is collected on a filter, washed, ignited, and weighed. In the above treatment the urea is decomposed according to the following formula : [C,H.]Sr,0, + 2H0 =200 J + aJSTH,] . A molecule of BaSOi corresponds, therefore, to a molecule of urea. 233 parts by weight of barium sulphate correspond to 60 parts by weight of urea. The extractive matters of the urine have no influence. But albumen and sugar heated with water to 200° C develop large amounts of carbonic acid; when the urine contains albumen and sugar, therefore, the method is not applicable. (Hoppe- Seyler.) § 66. Estimation of the Chlobine (Ohloeide of Sodium). I. MOHK'S METHOD. A. Principle. The principle of this method is easily understood. The urine filtered and acidulated with nitric acid is treated with a standard solution of nitrate of silver as long as a precipitate is produced ; but it is difficult to hit this point exactly without filtering, wherefore the method loses a little in convenience and accuracy. Mohr proposed, therefore, to add a few drops of a solution of neutral chromate of potassium in the titration of fluids containing chlorine, and then to perform the analysis as usual. The end reaction with this modification manifests itself in a beautiful and striking way, since, when all of the chlorine is precipitated by the solution ctf nitrate of silver, the next drop Digitized by Microsoft® 246 ANALYSIS OF THE URINE. gives a beautiful red precipitate of chromate of silver. But this change requires neutral or at least faintly alkaline fluids, and on no account should there be any free acid present on account of the ready solubility of the chromate of silver in acids. But though this method is admirable in pure fluids containing chlorine, in its application to the urine considerable difficulties are encountered, which are caused by the necessity of its having a neutral reaction. Many comparative experiments which I con- ducted first by Liebig's method, then by Mohr's, and finally gravimetrically, gave me always too high a result when titrated with a nitrate of silver solution after the addition of chromate of potassium. The reason of this is readily seen. If the titra- tion is carried out exactly according to Mohr's method, and a few drops of a solution of chloride of sodium are now added until the color of the fluid has become pure yellow again, in order to decompose the chromate of silver, the precipitate which is formed now is not pure chloride of silver. If, the light hav- ing been shut off, it is filtered, and after washing treated with cold dilute nitric acid, it becomes colored, and a not inconsider- able amount of silver may be detected in the filtrate by hydro- chloric acid. There is no doubt that oxide of silver in a neutral fluid is precipitated by coloring and extractive matters, and also by uric acid, wherefore an inexactness of the method must be the result. Phosphoric acid does not disturb the result, since chromate of silver is precipitated before the phosphate. (Compare § 13, C, 4.) (Analytical Experiments.) Even in acid solutions the coloring and extractive matters, etc., are not wholly without influence, and I prefer, therefore, to completely destroy these substances according to Mohr's propo- sition by evaporating the urine after the addition of a little pure nitrate of potassium and heating the residue to a dull red heat. B. Preparation of the Solutions. 1. Standard Nitrate of Silver Solution. This solution must contain 18469 grm. of stiver to the liter, so that each cc. corre- sponds to 10 mgrm. of chloride of sodium or 6-065 mgrm. of chlorine. Therefore 18 469 grm. of chemically pure silver are dissolved in nitric acid, the solution is evaporated to dryness on the water bath, heated until all of the free nitric acid is re- moved, the residue taken up with distilled water, and the solu- tion thus obtained diluted to a liter. If chemically pure fused Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 347 nitrate of silver is at our disposal, we can simply weigh off 29-075 grm., dissolve it in water, and dilute it to a liter. _ 2. Chromute of Potassium Solution. A cold saturated solu- tion of neutral chromate of potassium. C. Performance in Urine. 5 or 10 cc. of urine are introduced into a small platinum dish, 1 or 2 grm. of nitrate of potassium free from chlorine are added, and it is evaporated to dryness on the water bath. The residue is then heated over a free flame at first gently, after- ward stronger, until the carbon is completely oxidized and the residue is obtained as a white, fused, saline mass. The opera- tion readily and surely succeeds in this way, since the great excess of nitrate of potassium greatly diminishes the deflagra- tion, which is otherwise violent. The perfectly white saline mass is then dissolved in a little water, the solution is turned into a beaker, and the platinum dish carefully rinsed with water from a wash bottle. Very dilute pure nitric acid is added drop by drop to the alkaline fluid until a feebly acid reaction has resulted, which is then neutralized by as much precipitated calcic carbonate as can be contained upon the point of a knife. The excess of calcic carbonate is not filtered off before the titra- tion, since it in no wise prevents the end reaction. Two or three di'ops of the solution of chromate of potassium are added to the mixture, and then the neutral silver solution is allowed to flow into it with constant stirring, until a distinct reddish tinge is produced, which is permanent also after stirring. The reac- tion is very beautiful ; the fluid, at first of a light canary-yellow color, shows in the places where the silver solution falls red spots which disappear on stirring as long as chloride of sodium is still present. But as soon as the latter is completely decom- posed by the addition of the silver solution, the next drop shows a permanent reijxiish tinge of chromate of silver, which indicates the end of the experiment. Each cc. of the silver solution used up to this point indicates 10 mgrm. of chloride of sodium or 6'065 mgrm. of chlorine. If, for example, to 5 cc. of urine we have used 5 cc. of the solu- tion of silver, they contain 50 mgrm. of NaCl, and 1,000 cc. of the urine, 10"0 grm. NaCl or 6'065 grm. chlorine. Pribram* destroys the organic matters at a boiling tem- * Zeitschrift fur analyt. Chemie, Band 9, p. 428. Digitized by Microsoft® 248 ANALYSIS OF TEE URINE. perature with permanganate of potassium. 10 cc. of urine are lieated with 50 cc. of permanganate of potassium solution (1 or 2 grm. of the salt in a liter), and the chlorine in the filtrate is determined as usual. I have not obtained good results by this method. In my experiments 10 cc. of normal urine often de- composed four times as much chemically pure permanganate of potassium as Pribram states. There is found in this way, as is easy to prove, a considerable amount of oxalic acid, and the titration with the silver solution not rarely gave, especially in concentrated urines, considerably more chlorine in the clear, tolerably dilute filtrate than the method described above, which I, therefore, unconditionally prefer. (Analytical Experiments.) Liebig's method * of estimating chlorine with mercuric ni- trate, aside from the fact that in many cases it fails, unless car- ried out very exactly, frequently gives absolutely erroneous results. In regard to easy manipulation and certain success, it is far behind the method with silver; therefore I content myself with referring to the original treatise in regard to it. 1. Modification in Urine containing Iodine and Bromine. On account of the readiness with which the iodide and bro- mide of potassium go over into the urine, these substances must be considered in an accurate estimation of the chlorine. According to Salkowski, this error is most easily avoided as follows : 10 cc. of the urine are evaporated with nitre as usual, and ignited, the residue is dissolved in water, acidified with sulphuric acid, and the iodine removed by shaking with bi- sulphide of carbon. If the nitrite which forms on fusing does not suffice to set free all of the iodine present, it is advisa- ble to add a few drops of a solution of nitrite of potassium to the acidulated urinary fluid before it is shaken with bisulphide of carbon. The aqueous solution is finally neutralized with carbonate of sodium, evaporated and titrated with nitrate of silver as usual II. METHOD OF J. VOLHAKD AND A. FALCK. A. Principle. This method is founded on the behavior of sol- uble sulphocyanides toward solutions of silver and ferric salts. Soluble sulphocyanides produce in silver solutions a white pre- cipitate similar to chloride of silver, which is insoluble in dilute * Annalend. Cliem. u. Pharm., Band 85, p. 297. Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 249 nitric acid. A like precipitate of sulphocyamde of silver with a solution of nitrate of silver is given by the blood-red solution of sulphocyanide of iron, and the color of the latter at last com- pletely disappears. If, therefore, a solution of sulphocyanide of potassium is added to an acid solution of nitrate of silver to which a little ferric sulphate has been added, every drop of the sulphocyanide solution at first produces a blood-red cloud, which, however, quickly disappears again on stirring, while the fluid becomes milk-white. It is not until all of the silver is precipitated that the red color of the sulphocyanide of iron re- mains permanent, and at the same time the end of the experi- ment is reached. The reaction is extremely delicate, so that this method is not inferior to the first in point of sensitiveness, and it has the advantage that the titration can be undertaken in an acid solution. B. Preparation of the Solutions. 1. Standard Nitrate of Silver Solution. Description, see § 66, 1, B, 1. Each cc. corresponds to 10 mgrm. of chloride of so- dium or 6 '065 mgrm. of chlorine. 2. Solution of Iron Oxide. A cold saturated solution of crys- tallized ferric alum free from chlorine, or a solution of ferric sulphate, which contains about 50 grm. of iron oxide in the liter, is used. 3. Standard Solution of Sulphocyanide of Potassium. Since sul- phocyanide of potassium cannot be easily weighed accurately, 10 grm. are dissolved in a liter of water and this solution is standardized by the silver solution. For this purpose 10 cc. of the silver solution are measured off, 5 cc. of the iron solution are added, and then pure nitric acid is added drop by drop until the mixture appears colorless. If the sulphocyanide of potas- sium solution is then allowed to flow into it from a burette, every drop at first gives a blood-red color, which immediately disappears on stirring. When all of the silver is precipitated as sulphocyanide of silver, the next drop of the sulphocya- nide of potassium solution gives a permanently red color to the fluid which indicates the end of the experiment. If, for example, to 10 cc. of the silver solution 9-6 cc. of the sulphocyanide of potassium solution have been used before the red coloration is permanent, 960 cc. of the latter are measured off, and this is diluted with 40 cc. of water to make a liter. Both solutions Digitized by Microsoft® 250 ANALYSIS OF THE URINE. must now be equivalent, whicli is to be determined by titrating again. 0. Performance of the Analysis toitli Urine. 5 or 10 cc. of urine after the addition of 1 or 2 grm. of nitrate of potassium free from chlorine are evaporated and ignited as mentioned above, § 66, 1', 0. Since the nitrous acid which is formed in this operation prevents the end reaction, the fused saline mass is dissolved in water, acidulated with nitric acid, and then the chlorine is precipitated with an excess of the standard silver solution. After this mixture has been warmed on the water bath for a time to completely remove the nitrous acid it is al- lowed to cool, 5 cc. of the iron solution are added, and then sulphocyanide of potassium solution equivalent in strength to the silver solution is added while constantly stirring until the excess of the silver added is precipitated, which point is recog- nized by the permanent red color of the mixture. The differ- ence then between the number of cc. of the silver and sulpho- cyanide solutions corresponds to the chlorine contained in the urine. If, for example, at first 12 cc. of the silver solution were added to 10 cc. of urine, and 4 cc. of the sulphocyanide solution were required to titrate back the excess, the amount of chlorine in the urine corresponded to 12 — 4 = 8 cc. of the silver solution = 8'0 grm. of chloride of sodium or 4'852 grm. of chlorine in the liter of urine. § 67. Estimation of Phosphoric Aom, A. Principle. If a hot solution of a phosphate dissolved in water or acetic acid is treated with a solution of acetate or nitrate of uranium, when free acetic acid is present, a precipi- tate of the phosphate of uranium occurs at once. If the solu- tion contains salts of ammonium in large amount, the precipitate also contains ammonia. The phosphate of uranium thus pre- cipitated contains 80'09 parts of uranium oxide to 19'91 parts of PO5, and appears as a whitish-yellow precipitate with a faint greenish tinge, which is completely insoluble in water and acetic acid, but is soluble in the mineral acids. Since the precipitate is slimy and does not easily settle, the end of the reaction can- not be perceived in the fluid by stopping the precipitation; therefore, to ascertain whether all of the phosphoric acid is Digitized by Microsoft® QUANTITATIYE ESTIMATIONS. 251 precipitated, a slight excess of uranium oxide must be added, ■wliich can be detected with ease by the very delicate reaction of the uranium salts with ferrocyanide of potassium. Uranium salts, as is well known, give a reddish-brown precipitate with ferrocyanide of potassium, by which the slightest traces of uranium oxide are indicated by a corresponding reddish-brown coloration of the fluid. The uranium oxide once precipitated is not decomposed by ferrocyanide of potassium, as is the freshly precipitated ferric phosphate ; therefore to test for an excess of uranium a drop of the mixture may be brought directly in con- tact with the solution of ferrocyanide of potassium. If there is no free oxide of uranium present, the mixture does not become colored, but the slightest excess of oxide of uranium is most certainly recognized by a corresponding red color. Moreover, phosphate of uranium is a perfectly stable compound, and in a solution containing an excess of uranium does not, like ferric phosphate, change into a more basic compound; therefore, when the end reaction has once distinctly occurred, it may be produced again even after standing for days, which by the old method with ferric chloride was not the case even after a few minutes, for which reason the latter method is highly unsatis- factory and faulty. In the presence of acetate of sodium, however, the reaction of the ferrocyanide of potassium on uranium salts is not so delicate as in pure aqueous solutions. It is easy to be convinced of this if 50 cc. of water and 50 ce. of a solution of acetate of sodium, which contains 0"5 gram of the latter and 1 gram of free acid, are treated side by side with 0*2 cc. of the same solu- tion of uranium and both tested with ferrocyanide of potassium. The distilled water will immediately show a very distinct brown color, while the solution of acetate of sodium gives a much feebler reaction, which gradually grows darker after a time. If the amount of acetate of sodium is large, the reaction at first entirely, fails and appears only after a long time on the further addition of ferrocyanide of potassium. This circumstance is of the greatest importance, since in the titrate tion of phosphoric acid with uranium salts (for example, in 50 cc. of urine) soTnetimes more and sometimes less acetate of sodium is added, so thai sometimes more and sometimes less uranium solution wiU be required with the same amount of phosphoric acid to obtain the end Digitized by Microsoft® ANALYSIS OF THE URINE. reaction with ferroeyanide of potassium, and an error will thus he committed, which, however, is readily ofwiated iy always taking a like volume of fluid and treating this constantly with the same amount of acetate of sodium hefore the titration. B. Preparation of the Solutions. 1. Standard Phosphoric Acid Solution. It is well to have this of sucli a concentration that 50 cc. of it contain 0*1 gram. PO5, so that it approaches normal urine in regard to the amount of phosphoric acid as nearly as possible. It can be readily prepared from chemically pure, well-crystallized phosphate of sodium which has not been exposed to the air. The pure crys- tals are rubbed very fine, dried by pressing between filter paper, 10'085 grm. are accurately weighed off, and dissolved to a liter. 50 cc. then contain exactly O'l grm. PO5. 2. Solution of A cetate of Sodium. I have convinced myself by many experiments that 0*5 grm. of acetate of sodium is sufficient in all cases for 50 cc. of urine. Therefore 100 grm. of acetate of sodium are dissolved in 900 cc. of water, and this solution is brought up to a liter by 100 cc. of concentrated acetic acid. In the titration 50 cc. of urine are treated with 5 cc. of this acid solution of acetate of sodium. 3. Uranium Solution. Pure commercial oxide of uranium or yellow double carbonate of uranium and sodium is dissolved in pure acetic acid, especially free from empyreumatic matters, the solution is diluted and it is standardized with the phosphate of sodium solution a. I have found it advantageous to so ar- range the uranium solution that 1 cc. of it precipitates and indi- cates only '005 grm. of phosphoric acid. 50 cc. of our solution of phosphoric acid a = 01 grm. of PO,, and therefore will need exactly 20 cc. of the uranium solution, which must contain first 04023 grm. of oxide of uranium to precipitate the PO5, and second, a slight excess of oxide of uranium to indicate the end reaction. Therefore 50 cc. of the phosphoric acid solution a (0.1 grm. PO5) are measured off, allowed to flow into a beaker, 5 cc. of the acid solution of acetate of sodium b are added to it, and it is heated on the water bath to 90° or 100° C. The uranium so- lution is now allowed to flow into it, and it is tested after each i cc. for the end reaction. For this purpose one or two drops of the mixture are spread out on a white porcelain surface, and then a small drop of a feebly yellow-colored solution of ferro- Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. ^ 253 cyanide of potassium is introduced into its centre by means of a slender glass rod. Even if there is only a trace of an excess of oxide of uranium in tlie mixture, a reddish-brown island will form where the ferrocyanide of potassium solution is introduced, and, surrounded by the colorless or faint-yellow fluid, can be perceived with the greatest distinctness. I prefer this method to any other ; if after repeated testing and renewed addition of uranium solution a faint end reaction is finally o^ained, it is again heated a few minutes on the water bath and tested once more. If now the reaction appears distinctly, the experiment is ended. 50 cc. of our phosphoric acid solution should re- quire 20 cc. of the uranium solution; each cc. of the latter should, therefore, precipitate and indicate 5 mgrm. of PO5. Supposing we had used 18 "0 cc. of uranium solution to 50 cc. of the PO5 solution, we must add 20 cc. of water to every 180 cc. of the solution. Therefore one liter of the uranium solution is measured off, the necessary amount of water is calculated and added. In our case 111-2 cc. of water must be added to 1,000 cc. of the uranium solution, in order to obtain the desired con- centration. It is well, however, not to add the calculated amount of water at once, but a little less, test again with the phosphoric acid solution, and finally complete the uranium so- lution. If, for example, we have used the second time 19*8 cc. of the uranium solution to 50 cc. of the PO5 solution (01 grm. of PO5), we now add to every 198 cc. of the same 2 cc. of water, and make a new and thereby final test with the phosphate of sodium solution. Such a uranium solution, each cc. of which precipitates 5 mgrm. of PO5, and which at the same time con- tains a slight excess of oxide of uranium for the end reaction, must contain 20-3 grm. of pure oxide of uranium in. the liter. (Equivalent of uranium — 60.) C. Performance with the Tiring. a. Estimation of the Total Phosphoric Add. 1. 50 cc. of urine, previously filtered, are put into a beaker, 5 cc. of the acetate of sodium solution are added, heated on the water bath, and then the uranium solution is allowed to flow into it from a Mohr's burette divided into jV cc. "When the precipitate no longer increases, which can be observed quite readily if the uranium solution is allowed to flow slowly down the side of the glass without stirring, the test is performed. Digitized by Microsoft® 254 ANALYSIS OF THE UBINE. For this purpose one or two drops of tlie mixture are spread out on a white porcelain surface and a drop of a faintly yellow- colored solution of ferrocyanide of potassium is added to the centre of it by means of a slender glass rod. If there is a slight excess of oxide of uranium present, where the ferrocyanide of potassium solution is added an island of reddish-brown color is formed, which surrounded by the colorless or slightly yellow fluid may ""be observed with the greatest distinctness. If a feeble end reaction has taken place, the heat is continued for a short time (1 or 2 minutes) over the water bath and it is tested again ; if now the reaction remains distinct, if the color obtained corresponds to the tint at which the uranium solution was originally standardized, the experiment is ended. But in the other case the addition of the uranium solution is continued until the end reaction comes out distinctly and is permanent. But if through the careless addition of the uranium solution the proper end point shall have been exceeded, and therefore, if on the addi- tion of the ferrocyanide of potassium a deep brown color occurs immediately, then, according to circumstances, 10 or 20 cc. of urine are added to the mixture and the titration is continued with a more careful addition of the uranium solution until the right tint is reached. As was observed above, acetate of sodium retards the reaction of ferrocyanide of potassium with oxide of uranium, therefore the color gradually becomes darker, and care must be taken not to make a mistake. At all events we should accustom ourselves to regard the first very feeble brownish coloring in the centre of the drop, which can be brought out again in the same tint after further heating on the water bath (2 or 3 minutes), as the end of the experiment, though after the lapse of 10 or 15 minutes the brown color will increase in intensity. Pincus and Bodecker, both of whom likewise pro- posed the oxide of uranium for the same purpose, perform the analysis in the cold, but I unconditionally prefer a hot fluid, since the complete separation of the phosphate of uranium takes place very much quicker in hot fluids. If to 50 cc. of urine, for example, 20 cc. of uranium solution have been required to pro- duce the feeble but permanent reaction on heating, it contains 0-100 grm. of PO5, which can readily be reckoned for the twenty- four hours' amount. 2. The results are more exact when all of the phosphoric acid Digitized by Microsoft® QTTANTITATIYE ESTIMATIONS. 255 is precipitated from tlie urine by a solution of magnesium, and the phosphoric acid is titrated as above in the washed precipi- tate. For this purpose 50 cc. of urine are precipitated with magnesium mixture (a clear mixture of sulphate of magnesium, chloride of ammonium, and ammonia), and are allowed to stand several hours for the complete separation of the precipitate. The ammonio-magnesian phosphate is collected on a small filter, washed with water containing ammonia (one part of ammonia and three parts of water), and after the filter has been broken through it is washed into a beaker. After heating on the water bath acetic acid is added, drop by drop, until it is com- pletely dissolved, it is diluted to 50 cc. with water, 5 cc. of the acetate of sodium solution are added, and the fluid is titrated with the uranium solution just as recommended above. This roundabout way is necessary only in the rarest cases, since the results are very satisfactory also when the urine is directly analyzed. Generally a few tenths of a cubic centimeter less of the uranium solution would be required by this second method in one and the same urine, which in the daily amount of urine of 1,500 cc. amounts to about 015 or 0-2 grm. PO5. b. Determination of the Phosphoric Acid combined with the Al- kaline Earths. In order to determine only the amount of phosphoric acid combined with the alkaline earths, 100 or 200 cc. of the filtered urine, according to its concentration, are treated with ammonia until the reaction is alkaline, and it is then allowed to stand twelve hours. The earthy phosphates separated during this time are collected on a filter, and washed with water containing am- monia (one part of ammonia and three parts of water). When this is accomplished the filter is broken through, the precipi- tate washed into a beaker, and dissolved by the aid of heat in as little acetic acid as possible, and the phosphoric acid titrated, after 5 cc. of the acetate of sodium solution have been added and the whole volume has been brought to 50 cc, with the uranium solution as described under a. Example : 50 cc. required 184 cc. of the uranium solution for the precipita- tion of the total phosphoric acid = 0-092 grm. phosphoric acid. In 1,000 cc. there were, therefore, I'SIO grm. To determine the phos- Digitized by Microsoft® 256 ANALTSIS OF THE URINE. phoric acid combined with the alkaline earths there were required for 100 cc. of urine 6 cc. of uranium solution = 0'03 grm. of PO5. In 1,000 cc. there were, consequently, 0-300 grm. The urine contains then , a. Total PO5 =1-840 grm. b. PO5 combined with the earths - 0-300 " c. PO5 combined with the alkalies = 1-540 " § 68. Estimation of the Degeee op Acidity. A. Principle. Since the acid reaction of a urine does not de- pend alone on the acid phosphate of sodium, but the presence of free acids may also contribute to it, as, for example, lactic acid, etc., we must be contented in estimating the amount of acidity to compare its power of saturation with that of some known acid. Crystallized oxalic acid is selected for this pur- pose, and in this determination, therefore, we must establish how much oxalic acid the free acid present in a stated amount of urine corresponds to. We gain our object by accurately neutralizing the known amount of urine with an alkaline solu- tion, each cc. of which corresponds to a fixed amount of oxalic acid ; sodie hydrate solution is best for this purpose, since it does not lose its efficacy by volatilization as ammonia does, and at the same time it shows the point of neutralization very dis- tinctly. B. Preparatitm of the Solutions. 1. Standard Oxalio Acid Solution. This serves us for stan- dardizing the sodic hydrate solution. It is prepared by dis- solving 1 grm. of pure oxalic acid which has not effloresced, and diluting it to 100 cc. Each 10 cc. of this solution contain 100 mgrm. of oxalic acid. 2. Tincture of Litmus. 3 grm. of litmus are digested for a long time with 20 grm. of water, and the deep blue solution obtained is filtered. 3. Sodic Hydrate Solution. This is prepared as usual from carbonate of sodium and quicklime, and then its strength is determined with the oxalic acid solution, a. Each cc. must indi- cate 10 mgrm. of oxalic acid. 10 cc. of the oxalic acid solution are accurately measured by Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 257 means of a pipette, it is allowed to flow into a small beaker, and is colored distinctly red by a few drops of the tincture of litmus. The glass is then put on a white background, and the dilute sodic hydrate dropped into it until the fluid has become blue again. This point can be observed with the greatest dis- tinctness, since the transition of the red color to the blue takes place quite suddenly. Suppose that 6 cc. of the sodic hydrate solution have been required for this purpose, they correspond to 100 mgrm. of oxalic acid ; we therefore add 400 cc. of water to 600 cc. of the sodic hydrate and thus obtain a liter of alka- line solution, each cc. of which corresponds exactly to 10 mgrm. of oxalic acid. We now assure ourselves of the accuracy of our dilution by a second titration ; if the blue color takes place after the last drop of 10 cc. has been added, then the sodic hydrate may be used for determining the acid in the urine. C. Performance. On account of the color of the urine itself it is impossible to add the tincture of litmus directly to it in titration, since the change from red to blue cannot be observed with sharpness in a colored fluid. With urine, therefore, we must have recourse to litmus paper in order to determine the point of saturation, and must perform the analysis as follows : After 50 or 100 cc. of urine are measured off and introduced into a beaker, the standard sodic hydrate is added drop by drop. After each ^ cc. used, a drop of the fluid is taken out with a glass rod and placed on a small piece of sensitive blue litmus paper. If the spot where the drop lies becomes red after a few seconds, the addition of sodic hydrate is continued untU no more reddening of the paper is observed. A drop is then put on red litmus paper, and if it is made blue, the volume of sodic hydrate which was used is noted, and the ex- periment is repeated with a new quantity of the urine, but a few drops less are added; by frequent testing the point of satu- ration is very accurately determined. § 69. Estimation op the Sulphueic Acm. A. Principle. The method of estimating sulphuric acid de- pends simply on the addition of a solution of chloride of barium of known strength to a definite quantity of urine, as long as a 17 Digitized by Microsoft® 358 ANALYSIS OF TEE UBIME. precipitate of sulphate of barium is produced by it. But it is to be noticed tliat as soon as an amount of chloride of barium exactly equivalent to the quantity of sulphuric acid has been added to a fixed volume of urine feebly acidified with hydro- chloric acid, a so-called neutral point occurs in which the fil- trate shows a slight cloudiness, both with sulphuric acid and with a solution of chloride of barium. In the solution thus formed chloride of potassium, chloride of barium, and sulphate of potassium must be considered to be in a certain condition of equilibrium ; now, if chloride of barium or sulphate of potas- sium is added, the equilibrium is destroyed and a precipitation of sulphate of barium results. In the titration of sulphuric acid in urine with a solution of chloride of barium, either the latter can be added until the neutral point is reached, that is, until in the filtrate both by another drop of the chloride of barium solution, and in another specimen by a drop of a solu- tion of sulphate of potassium, a faint cloudiness is produced, or until only a slight excess of barium is indicated in the fil- trate by sulphate of potassium. The solution of chloride of barium must naturally have a ■different concentration, according as the one or the other end reaction is chosen. If the titration is carried to the neutral 3)oint, it is well to make the solution of chloride of barium of ;such a strength that 1 cc. of it contains an amount of barium exactly equivalen,t to 10 mgrm. of sulphuric acid; but in the second case, the barium solution must contain a slight excess of barium for each cc. to precipitate 10 mgrm. of SO3 and to in- dicate the end reaction by a slight barium reaction in the fil- trate. I have convinced myself that the neutral point can be attained quite readily, and that the results when the titration is carried to this point are quite satisfactory ; and, therefore, I prefer to regard the titration of sulphuric acid as ended once for all, when in two specimens of the clear filtrate an equally faint cloudiness is produced by chloride of barium and by sul- phate of potassium. Mulder first called attention to this neu- tral point, in the titration of a solution of silver by chloride of sodium. B. Preparation of the Solutions. 1, CMoride of Barium Solution. This solution must be so concentrated, that 1 cc. of it precipitates exactly 10 mgrm. of Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 259 sulphuric acid. It is prepared simply by dissolving 30 "5 grm. of powdered, crystallized chloride of barium which has been dried in the air, and diluting the solution to a liter. 1 cc. then corresponds to 10 mgrm of anhydrous sulphuric acid. 2. Solution of Sulphate of Potassium. This must be exactly equivalent to the chloride of barium solution; it is prepared by dissolving 21-778 grm. of powdered, chemically pure, sul- phate of potassium dried at 100° C, and diluting the solution to a liter. 1 cc. then contains 10 mgrm. of sulphuric acid, and is exactly equivalent to the solution of chloride of barium. C. Performance. 100 cc. of the urine to be examined are put into a narrow long-necked flask (fig. 29), treated with twenty or thirty drops of hydrochloric acid, and heated on the water bath ; then 5 or 8 cc. of the chloride of barium solution are allowed to flow into it from a burette and to stand until the sulphate of barium has settled. At a boiling temperature it becomes thick quite rapidly and then deposits very well. When the fluid has become clear another cc. of the chloride of barium solution is added, it is heated, and ten or twelve drops of the urine are fil- tered through a small filter the size of a thimble into a very small narrow test tube about two inches long, and tested to see if there is any further precipitation by the chloride of barium or not. If the latter is the ease, a few drops of sulphate of potas- sium solution are added to a second specimen of the filtrate by which an excess of the baric chloride solution is shown. But if in the first specimen we still get a distinct cloudiness with the baric chloride solution, the fiuid is poured back again into the flask, the filter and tube ai^e rinsed with fiq. a little water and this is added to the urine also. If thus far about 8 cc. of chloride of barium solution have been used, 1, 2, 3, or 4 more are added, according to the intensity of the reaction, which by a little practice can readily be estimated by the degree of cloudiness which takes place at the first test, the whole is heated to boiling, a few drops are again filtered off for testing, and this is continued until at last there is no more cloudiness pro- duced in the filtrate by chloride of barium. If this is the case after using, for example, 13 cc, and if sulphate of potassium Digitized by Microsoft® 260 ANALYSIS OF THE URINE. now in a new test shows a distinct excess of barium, we know that the right point must lie between 12 and 13 cc, and the 100 cc. of urine must contain between 120 and 130 mgrm. of sulphuric acid. 100 cc. of the urine are, therefore, measured off anew, treated with 20 or 30 drops of hydrochloric acid, 12 cc. of the chloride of bariuin solution are added immediately, heated, and a few drops of the filtrate tested with -^ cc. of the baric chloride solu- tion. If a distinct cloudiness takes place immediately, the fil- trate and the original fluid are united again, -^-^ cc. more of the baric chloride solution are added, the filtrate is again tested, and this is continued till at last the chloride of barium solution shows only a very faint cloudiness after several seconds. If a second specimen of the filtrate is now tested with a few drops of the sulphate of potassium solution, it will be found that a slight cloudiness occurs here also after a few seconds, so that the neutral point is reached and the titration is ended. If we have used up to this point about 12*8 cc. of the chloride of barium solution, the 100 cc. of urine contains 0'128 grm. of SO3, from which the amount in twenty-four hours can be very easily reckoned. But if by an incautious addition of the chloride of barium solution the point has been far exceeded in the first experiment, a few cc. of the exactly equivalent sulphate of potas- sium solution are added, and the boundary is determined by a more careful addition of the baric chloride solution. The num- ber of cc. of the sulphate of potassium solution added must naturally be subtracted from the whole number of cc. of the baric chloride solution used, when making the calculation. Although the operation appears long it can be performed in half an hour very easily and gives satisfactory results. 100 cc. of urine contained 0'129 grm. of SO3 as determined by weighing, and by titration to the neutral point it was estimated to contain 0'128 grm. 100 cc. of another urine gave 0'139 grm. SO3, deter- mined by weighing, and 0"137 grm. SO3 by titration. (Analytical Experiments.) Gravimetric Determination. 100 cc. of filtered urine are measured off with a pipette, it is allowed to flow into a small beaker, heated on the water bath, a little hydrochloric acid added, and then chloride of barium solution in slight excess. The sulphate of barium formed will Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 261 settle very quickly and the supernatant fluid will become clear. The whole precipitate is collected on a small filter, the weight of whose ash is known, it is then washed with hot water until the wash water is no longer made cloudy by sulphuric acid, and dried as soon as the washing is finished. The sulphate of barium obtained must then be ignited ; it is, therefore, trans- ferred from the filter to a small weighed platinum crucible. After the filter has been ignited on the cover of the crucible, the cover is placed on the latter, taking care, however, that the ash does not come in contact with the precipitate, and it is ig- nited strongly for a short time. But since organic matters are always precipitated from the urine with the sulphate of barium, a little sulphide of barium is formed on heating ; therefore after the crucible has become cold again its contents must be mois- tened with a few drops of dilute sulphuric acid and be heated once more until the excess of sulphuric acid is expelled. The crucible is then allowed to cool in a desiccator over sul- phuric acid and is afterward weighed. If the weight of the crucible and of the filter ash are subtracted from the total weight, we obtain as the difierence the amount of sulphate of barium precipitated, from which it is easy to calculate the sul- phuric acid, since 100 parts of sulphate of barium correspond to 34"33 parts of sulphuric acid. §70. 1. Estimation of Sugae by Fehling's Method. A. Principle. The method of estimating sugar in the urine is founded on its property, mentioned in § 25, T>, 7, of precipi- tating the copper in the form of red cupreous oxide from alka- line solutions of sulphate of copper. If a copper solution of known strength is used, a fixed volume of which is exactly re- duced by a certain amount of grape sugar, we can easily accu- rately estimate the sugar contained in solutions of unknown strength, if we determine the volume which is just sufficient to completely decompose a measured amount of the standard cop- per solution. 180 parts by weight of grape sugar (=1 equiva- lent) precipitate the copper from 1247"5 parts by weight of cupric sulphate (=10 equivalents). Digitized by Microsoft® 262 ANALYSIS OF TEE UBINE. B. Preparation of the Copper Solution. 3^'639 grm. of pure crystallized sulphate of copper are dis- solved in about 200 grm. of water ; on the other hand 173 grm. of crystallized chemically pure potassio-sodic tartrate are dis- solved in 500 or 600 grm. of sodic hydrate of specific gravity 112, and the sulphate of copper solution is gradually added to this alkaline solution. The clear mixed fluid is then diluted to one liter. 10 cc. of this copper solution are exactly reduced by 0'05 grm. of grape sugar. If the copper solution is to be kept for a long time, it is absolutely necessary to place it in small bottles (40 to 80 grm.), which are to be closed with good stoppers, sealed, and then stored in a cool place. C. Performance. In order to obtain favorable results by this method it is a ne- cessary requisite that the urine to be tested for sugar as well as the copper solution shall be largely diluted. It is well to treat 10 cc. of the copper solution with 40 cc. of distilled water, and to dilute 10 or 20 cc. of the urine, which has been previously filtered, to ten or twenty times its own volume, so that at most it contains J per cent, of sugar. Then after heating the measured and diluted 10 cc. of the standard copper solution in a small flask over a lamp nearly to the boiling point, the urine also diluted is added from a burette, at last drop by drop, until complete reduction has taken place, that is, until the fluid has become colorless. In doing this, however, there are many things to be heeded. As soon as the first drops, of the saccharine fluid fall into the hot copper solu- tion, the separation of suboxide commences. The mixture ap- pears reddish brown with a greenish tinge on account of the suspension of the red cupreous oxide in the blue solution ; the greater the addition of the solution of sugar, however, the richer and redder the precipitate becomes, and it is not until the latter has assumed a deep red color and the fluid has become per- fectly colorless that the experiment can be regarded as finished. The analysis is performed most accurately and quickly as fol- lows : As soon as the mixture in the flask, on very gentle boiling, and after the repeated addition of the diluted urine, commences to assume a red color, the flask is removed from the flame and the separated cupreous oxide is allowed to settle, which occurs the more readily and quickly the nearer the Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 263 point of complete reduction of tlie cupric oxide is readied. The faintest trace of blue color may be observed witli gyeat sharpness, if the flask is brought between the eye and a win- dow, and the fluid viewed by horizontal transmitted light. If we are still far from the end reaction, as remarked above, the cupreous oxide already separated deposits more slowly, but the blue color can still be seen very distinctly by transmitted light if the mixture is given a rotary motion while we look through it. Finally, the more nearly the blue disappears from the fluid, kept very near the boiling point always, the more carefully must we allow the sugar solution to run in ; but at last a point appears after the repeated addition of the latter and continued heating, at which the last blue shimmer disappears with one or two drops of the sugar solution, and gives place to a very faint yellow tinge. The reaction is now finished, and all of the cupric oxide is reduced; nevertheless we can be certain by further tests. We, therefore, filter some of the boiling fluid into three test tubes ; one specimen of the absolutely clear filtrate is acidulated with hydrochloric acid and tested with sulphuretted hydrogen water, while a second specimen, after acidulating with acetic acid, is treated with fer- rocyanide of potassium. Neither of the two reagents should change the fluid ; the first, therefore, must not color it black nor the second reddish brown or precipitate it at all. If the two behave indifferently we may conclude that all of the copper is reduced and precipitated, and that we have added a suffi- cient amount of the solution of sugar. It is well to take this into consideration, however, that the cupreous oxide very quickly oxidizes again and dissolves, therefore in testing the fluid it must be filtered off immediately after the end of the ex- periment, while boiling, since after it has cooled it will always have a bluish color on account of the cupric oxide which has been dissolved again. If no more undecomposed cupric oxide is found by means of the above reagents, an error may nevertheless have been made by having added too much of the urine, so that naturally the amount of sugar will be calculated less than it really is. There- fore, the third specimen of the clear, almost colorless filtrate is treated with a few drops of copper solution and heated to gentle boiling. Even when. only a trace of sugar has been Digitized by Microsoft® 264 ANALYSIS OF THE TJRINE. added in excess, after a short time there occurs a distinct red shimmer, which may be quite beautifully and readily appre- ciated by reflected light. When a great excess of sugar has been added the filtrate has a yellow color ; then there is nothing to do but to perform the analysis over again more carefully, which indeed is always to be advised as a test of accuracy. However, if" the experiment is performed in a small flask in the manner described, as was first suggested by A. Ziegler, the right end point may be obtained with great accuracy with a little experience, as I have demonstrated. The volume of urine used contains, therefore, as was men- tioned above, 0'05 grm. of sugar. Now since the amount of sugar in the fluid is inversely proportional to the volume used, to determine the per cent, of sugar in the urine, we must divide five by the amount in cubic centimeters of urine used, if it was not diluted; but if, for example, it was diluted to twenty times its volume, we must divide 20 X 5 = 100 by the number of cc. used. . Of the other constituents of urine it is probably the uric acid chiefly which is known to reduce the copper solution on boil- ing, and which may, therefore, influence the result. Fehling, for this reason, first precipitates the urine with basic acetate of lead. But Briicke disapproves of this precipitation, because, according to him, some of the sugar is precipitated at the same time. Pure fruit sugar produced from urine is, how- ever, not precipitated by ' basic acetate of lead, and it can at most, therefore, only be carried down mechanically. Fehling experimented with normal urine to which from 10 to 12 per cent, of sugar was added. But if we have a diabetic urine of about 8 per cent., when 10 cc. of it are diluted to 200 cc, we require to decompose 10 cc. of Fehling's solution only 12-5 cc. of this diluted fluid corresponding to 0'6 cc. of the original urine. The uric acid contained in 0-6 cc. of diabetic urine would be a very small amount. I have made several experiments with diabetic urine in order to convince myself of its action. a. 10 cc. of urine were diluted to 200 cc. and directly used for analysis. In several trials 12'3 cc. were required. b. 10 cc. of urine were diluted with 188 cc. of water and 2 cc. of basic acetate of lead, which were more than sufficient to pro- Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 265 duce complete precipitation, were added. After twelve hours it was filtered, and exactly 12-2 cc. were used to 10 cc. of the Fehling's solution. ^c. 150 cc. of urine were left at rest for forty-eight hours at 5° or 6° C. with 5 cc. of hydrochloric acid of 11 specific gravity. 10-33 cc, corresponding to 10 cc. of the original urine, were filtered from the separated uric acid, diluted to 200 cc, and used for analysis. In several trials 12-3 cc. were required. The same experiments were repeated several times with dia- betic urine of other days without any variation in the result worthy of mention by the different methods. But apart from this consideration, in many cases a precipitation with basic acetate of lead may be desirable, and when this is done in a urine previously diluted to at most 0*5 per cent., the amount of sugar precipitated will be none, or, at least, very slight indeed, as was determined by Fehling's experiments. If albumen is present, it must be removed; the urine is heated to boiling after the addition of a drop of acetic acid, the coagulum which forms is filtered off, carefully washed, and the filtrate obtained, diluted if necessary, is used for determining the sugar. 2. Estimation op the Sugae by Knapp's Method.* A. Principle. This method depends on the complete reduc- tion of cyanide of mercury in alkaline solution to metallic mer- cury by means of grape sugar at a boiling temperature. 400 mgrm. of cyanide of mercury require 10 mgrm. of anhydrous grape sugar. B. Freparation of the Solution. 10 grm. of pure dry cyanide of mercury are dissolved in water, 100 cc. of sodic hydrate of 1"145 sp. gr. are added, and the mixture is diluted to 1,000 cc. C. Performance. The analysis is performed as with Fehling's solution. 40 cc. of the cyanide of mercury solution are brought to the boiling point in a flask, and the urinary fluid containing about 3 per cent, of sugar is allowed to flow in until all of the mercury is precipitated. In the mixture of urine used we have had just 100 mgrm. of grape sugar. When the sugar solution flows into the boiling alkaline solution of cyanide of mercury, * Annalen d. Chem. u. Pharm., Band 157, p. 352. Digitized by Microsoft® 266 ANALYSIS OF THE UBINE. the mixture immediately becomes turbid, but clears up toward the end of the operation and then assumes a yellow color. In order to follow the course of the operation, from time to time a drop of the mixture is put on a piece of the finest Swedish filter paper, which is placed over a small beaker containing a little of the strongest sulphide of ammonium. If a brown spot is no longer formed on the paper, the experiment is ended. The re- action is still more delicate when a drop is placed on a strip of Swedish paper, and then a drop of sulphide of ammonium on a glass rod is held over it for about half a minute. At first the whole spot becomes brown, but toward the end a light-brown ring only forms on its edge, which can finally be distinctly recognized only when the transparent spot is held up toward a bright light. The fresh transparent spot remains wholly un- changed by sulphide of ammonium vapor at last, so that with a little experience the titration can readily be carried within yV cc. of the one-half per cent, solution. If the spot is allowed to dry finally, a clear-brown ring of sulphide of mercury always appears, since a neutral point seems to be. formed, as there always remains in solution a trace both of grape sugar and of cyanide of mercury, which is removed only by an excess of the one or the other. We must, therefore, regard the color of the fresh spot as the standard. For greater accuracy a few cc. of the fluid are at last filtered off, acidulated with acetic acid, and tested with sulphuretted hydrogen to see whether mercury is present or not. According to comparative investigations which my assistant, Mr. Pillitz, conducted with diabetic urine, Knapp's method gave results which coincided very well with Fehling's method. (Analytical Experiments.) The easy preparation of the solu- tion of cyanide of mercury and its absolute durability are de- cided advantages. 3. Estimation op Sugar by Ciecumpolaeization. a. With the Ventzke-Soleil Polarizer. A. The Polarizer. Fig. 30 shows the Soleil-Ventzke sac- charimeter A with the lamp which belongs with it. We will first consider the optical arrangement and then the employment of this ingenious apparatus. The light coming Digitized by Microsoft® qVANTITATIYE ESTIMATIONS. 267 from the lamp B first falls on a large Nicol prism at J, which, with the quartz plate at h cut perpendicular to the axis, can be turned around the axis of vision by means of the cogwheels m and p and the iron rod nm. At i there is a second fixed Nicol prism, and in front of it at A the soleil double plate made of quartz rotating to the right and left. In the front part of the Fig. 30. apparatus there is &i g & left-handed quartz plate cut perpen- dicular to the axis, and in front of it a compensator made of two right-handed quartz prisms, which prisms can be so shifted by means of a driving gear on the head, o, that the polarized light which traverses the apparatus has to pierce a thicker or thin- ner layer of right-handed quartz. At d there is again a Nicol prism which can be turned around the axis of vision by a small key at e, and lastly at the head of the instrument at he there is a small telescope to enable every eye to distinctly see the double plate standing at li. Then the glass tube filled with the urine to be examined and closed at both ends with glass plates is in- serted between p and p. The compensation prisms at / sup- port above a scale and nonius, which are best so divided that the parts of the scale to the right of the 0-point directly give the per cent, of grape sugar in 100 cc. of urine, when the ob- servation is made in a tube 200 mm. long at 17° 0. On the left of the 0-point a second scale gives under the same circum- stances the per cent, of albumen in 100 cc. of urine. If we Digitized by Microsoft® 2g8 ANALYSIS OF THE UBINE. place the compensator at/, by means of the thumb-screw o, in such a manner that the 0-mark of the nonius exactly corre- sponds with that of the scale, the two right-handed quartz prisms have together the same thickness as the left-handed quartz plate at g, and the two neutralize each other, so that the eye looking at a, when the two Mcol prisms at d and i are properly placed, will see the double plate Ji having exactly the same color. The same is the case if the examining tube is filled with distilled water and inserted between 7^/7. If the two quartz prisms are now shifted to the right or left by means of the screw 0, the two halves of the double plate h immediately appear unequally colored, just so if the compensator stands exactly on and the examining tube contains a fluid rotating to the right or left. If, for example, this is filled with diabetic urine, the compensa- tor must now be turned toward the right in order to restore again the deranged equality of color of the double plate. Lastly, it is of great importance to be able to give the double plate any shade of color desirable, since all eyes do not possess a like sensitiveness for all colors. For this purpose the back part of the apparatus situated next the lamp is of service. By means of the rod nm and the cogwheels m and p the quartz plate at h and the Nicol prism I can be turned around the axis of vision ; the former, therefore, since it is between a fixed Nicol prism, i, and a movable one, I, will run through all shades of color, and also allow only colored light to pierce the apparatus, by which the original color of the double plate may be varied at pleasure. Proper Arrangement of the Apparatus. First, the saccharimeter is so placed, as represented in fig. 30, that the brightest part of the illuminating lamp B sends the light through the lateral connecting tube r of the clay cylinder s, which has its outer surface blackened, directly in the axis of the apparatus ; then the observation tube, which has been exactly filled with distilled water, is placed between pyp, and the compensator is so arranged that the 0-point of the nonius coincides with the zero-point of the upper scale. If we now observe at a, by shortening or lengthening the telescope he we soon reach the point at which the picture appears clear and well defined and the fine line which divides the double plate into halves becomes sharply defined. If the double plate appears absolutely isochromatio Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 269 and if the isochromatism also remains in all the shades of color which we can give it by turning the rod nm, then the apparatus is in order ; in the other case the zero-point must be corrected. For this purpose everything is left unchanged except the Nicol prism at d, which is turned with the key at e a little to one side or the other, until the desired color of the two halves of the double plate has been attained. As a correction the scale is moved a little one way or the other by turning the screw o until the picture appears exactly isochromatic again. If we look at the scale and nonius now, the two zero-points must exactly co- incide ; in the contrary case a new adjustment must be made of the Nicol prism d. This correction, however, is only very rarely necessary ; if the instrument is carefully kept the zero- point remains constant for years. B. Process of Estimating Sugar. Diabetic urine can usually be directly examined in the polarizer if it is filtered so as to be ab- solutely clear. When the apparatus has been given the position shown in the figure, the 200 mm. long observation tube is filled with clear filtered urine, or urine which has been decolorized by animal charcoal if necessary, taking care, however, to avoid in- closing air-bubbles, and it is then laid between the points p and p in the apparatus. Then after the telescope has been sharply focused, the compensator is turned until the two halves of the double plate appear nearly isochromatic, and those shades of color are sought, by turning the Nicol prism at I to the right or left with the rod nm, in which the slightest difference in the color of the two halves of the double plate is most distinctly perceptible. A pale rose will meet this purpose best ; at all events, we may soon convince ourselves that all dark, fervid colors which the double plate gradually assumes on turning the rod nm are wholly unserviceable. Frequent practice of the eye will soon enable us to hit upon the right one. We can now proceed to an accurate adjustment of the picture, isochromatism of the two halves. The screw o is, therefore, seized, and the compensator moved back and forth until complete isochroma- tism of both halves is attained. The principal rule in this procedure is never to observe longer than ten seconds at a time.* ■■■ Tlie two glass plates whicli close the observation tube must not be pressed on too closely, since they may themselves easily give rise to double refraction and show colors with polarized light, which cause the rotation produced by the Digitized by Microsoft® 270 ANALTBia VF THE UBINE. Since the eye quickly habituates itself to nice differences of color, an accurate result can never be arrived at by a single adjustment and too long an observation. When at last, after several observations, we think that the two halves of the picture are isochromatic, we again turn the prism at I with the rod nm ; if the two halves of the plate remain abso- Ititely isochromatic in all the shades of color which the double plate now produces, then the experiment is finished; in the other case the compensator must be more accurately adjusted until at last the object aimed at is attained. The scale and nonius are now read off. The zero-point of the latter has removed consid- erably toward the right from the zero-point of the scale ; if it coincides with a mark of the latter, it shows with the obser- vation tube 200 mm. long as many per cent, of sugar in 100 cc. of urine as there are divisions from the zero-point of the scale to the zero-point of the nonius, since every line of the scale corresponds to 1 per cent, of sugar. If, however, the zero- point of the nonius lies between two divisions of the scale, we must seek a line of the scale of the nonius lying to the right which coincides with a line of the scale. When this is found, we count the divisions from the zero-point of the nonius to the one which coincides with the division of the scale inclu- sive. Each division on the nonius indicates yV per cent, of sugar. The whole per cents., therefore, are read off on the scale ; the tenths are read off on the nonius, for which a lens may be used with advantage. If the urine is too dark, the estimation is undertaken in an observation tube only 100 mm. long ; if it succeeds we have only to remember that every di- vision of the scale indicates 2 per cent, and every division of the nonius ^ per cent, of sugar. But if we do not attain our object in this way we must decolorize the urine by means of animal charcoal, or a measured volume of the urine is precipi- tated with a known volume of sugar of lead solution, filtered, and the clear colorless filtrate is examined. Of course the dilu- tion caused by the solution of lead is to be taken into account in the estimation. C. TJm Urine also contains Albumen. If albumen is present urine whicli is to be examined, to appear more or less erroneous. (Zeltschrift f. aualyt. Chemie, Band 8, p. 211.) Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 211 at tlie same time with sugar, it must be removed first, since, the reverse of sugar, it turns the plane of polarization to the left. The albumen in 100 cc. of urine is coagulated by heat- ing in a flask after carefully adding a little acetic acid, the fluid is filtered into a graduate and washed with water until the filtrate amounts to exactly 100 cc. again. After it has cooled it is examined with the polarizer. According to the comparative experiments of Tscherinoff * and my own considerable experience, there is no doubt that the figures obtained with the Ventzke-Soleil apparatus in diabetic urine often vary considerably from the chemical determina- tions. The difference may be either minus or plus. In the first case we must consider that the urine contains another re- ducing substance, but one which does not turn the plane of polarization, whether it is sugar optically inactive or some other substance, or that besides the ordinary grape sugar, which turns to the right, there is also a small amount of sugar or some other body which turns the plane to the left. In cases where only plus is the result, in my experience the rarer ones, we may assume that the diabetic sugar possesses, at least in part, a higher rotatory power than the ordinary grape sugar, or that another body is present which turns to the right but does not have a reducing action. (Analytical Experiments.) b. With the Polaristrdbometer of Wild. Pigs. 31 and 32 show Wild's polaristrobometer and the lamp which belongs with it. The brass column, F, stands on an iron tripod, E, and bears on its upper end the horizontally and ver- tically movable support, on one end of which is the polariscope, A, and on the other end the circular disk, K, with the Nicol- setting. The polariscope consists of a feebly magnifying tele- scope focused on infinity, before whose objective a double plate of calc-spar is placed, while in the focus of the objective there is a diaphragm with cross-hairs. The double plate, according to the theory of Savart's polariscope, is made of two 3 mm. thick plates of calc-spar cut at 45° to the optical axis, and with their principal planes crossing at right angles. At the other end of the polariscope the analyzing Nicol prism is so inserted that its principal plane stands horizontally, and includes with *Zeitschrift f. analyt. Chem., Band 6, p. 503. Digitized by Microsoft® 272 ANALYSIS OF TEE UBINE. that of the double plate an angle of 45°. A screen, M, at the ocular, serves to keep off the disturbing side light from the eye of the observer. Finally,- the polarizing Nicol is inserted in a shell, N, at the circle, K, and on its mounting is afterward placed the dark tube D. The circular disk and Nicol may be turned by the knob, C, by means of a toothed pinion. The index, I, for reading off the Fig. 31. position of the circular disk is put on the support of the latter and has a simple mark. The telescope, P, serves for reading off its position, and its ocular, B, lies immediately beside the ocular, A, of the polariscope. The division is lighted by a movable perforated mirror, S, at the objective end of this tele- scope, and a candle or gas flame at the proper height serves as the source of light. One half of the circle contains a division marked with grams, which extends from the zero-poiat to about 300 toward the right and 150 toward the left. Each interval of this division corresponds to 1 grm. of pure cane sugar, which is contained Digitized by Microsoft® qUANTITATIVE ESTIMATIONS. 273 Fig. 33. in 1,000 cc. of solution, and wlien a tube 200 mm. long is used. On the opposite half of the circle, on the contrary, there is a second division into degrees and i of a degree (entire circum- ference 360'), which serves to express the angle of rotation of the plane of polarization by any desired substances in an inde- pendent manner.* Lastly, a special bed serves to receive the observation tube between the circular disk and the polariscope. The gram division mentioned depends on the use of a homogeneous source of light, and, indeed, a yellow light of the refrangi- bHity of the line D. Fig. 32 shows the Bun- sen gas-lamp, which serves to produce this light. On the side arm, a, there is a small mova- ble wheel, r, on whose spokes small glass tubes with platinum wire fused into them can be fastened. These wires contain beads of chloride of sodium, which are turned into the front edge of the flame by means of the knob, h, and immediately produce a clear homogeneous yellow light. . The chimney, li, rests on the movable support,/, and ensures as steady a flame as possible. The lamp is so placed that the round opening, c, in the chim- ney, stands exactly in front of the opening, D, so that the field is illuminated perfectly symmetrically. In order to obtain the best possible results and at the same time to tire the eye least, it is well to place the apparatus in a dark room and carefully avoid every disturbing side light. When we have a sufficiently bright and perfectly homoge- neous light, about the mark 300 of the division, marking in grams, is brought into the field of the telescope, P, by turning the * The mechanicians, Hermann and Pflster, in Bern, who furnish Wild's Po- lar! strobometer of excellent finish at a price of about 300 marks ($75), have lately made instruments in which the circle is divided throughout in ^ degrees (860°), so that it is possible to read off the angle of rotation in all four quad- rants. 18 Digitized by Microsoft® 374 ANALYSIS OF THE URINE. knob, G, and on looking through the polariscope, A, a bright- yellow field is obtained, which is traversed by horizontal black Pig 33 a and 6 lines, and shows also the cross-hairs (fig. 33, a). If the latter do not appear sharply defined, the ocular of the telescope, A, is drawn out more or less, until they become so ; and now the horizontal black fringe will be most distinctly seen also. If we now turn the knob, C, again (in the di- rection of the arrow) the horizontal lines grad- ually become paler and at last wholly disap- pear. This point in Wild's apparatus shows that the instrument is adjusted, just as in Soleil's saccharimeter the same color of the two quartz halves indicates the same thing. If the instrument is accurately adjusted, when the lines com- pletely disappear, the index mark exactly corresponds with the zero-point of the circle division. If a slight deviation should appear here, its amount may either be taken into account by addition or subtraction in later measurements, or with the aid of the two correction-screws, at Q, the polariscope may be turned in its sheath, L, micrometrically to the left, until the horizontal lines completely disappear, while the index line re- mains at zero. (Fig. 33, 5.) Procedure in Estimating. According as the color of the per- fectly clear filtered urine is lighter or darker, the observing tube 100 or 200 mm. long is chosen for the estimation. We first bring the circle division, which is furnished with numbers running from to 100 and divided into \ degrees, into the field of the telescope, and adjust it exactly at the disappearance of the fringe, when about the division 50 will coincide with the index. Beading off the position is accomplished by estimating the tenth of a division at -^-^°, when by multiplying by two the -t° and the -^V" are changed to ^"5-° and j^^°, so that we can write them as decimals. After the starting-point has been determined the tube filled with urine is placed on the apparatus and we turn toward the increasing numbers until the fringes disappear again. If the first reading is subtracted from the new one, we obtain the angle of rotation a, from which the amount of sugar C, that is, Digitized by Microsoft® Q TTANTITA TIVB M8TIMA TIONS. 275 tlie weight of diabetic sugar present in a liter, is given in grams by means of tlie formula 0=1773 — L in which 1773 is the constant rotation of diabetic sugar ac- cording to Hoppe-Seyler's most recent determinations,* L the length of the tube in millimeters, and a represents the angle of rotation observed. The following table gives the results of these calculations for whole degrees and tubes 100 and 200 mm. long : ANGLE OF DEVIATION. 100 MM. 300 MM. 1° 17-73 8-865 2° 35-46 17-730 3° 53-19 26-595 4° 70-92 35-460 5° 88-65 44-325 6° 106-38 53-190 7° 124-11 62-055 go 141-84 70-930 9° 159-57 79-785 10° 177-30 88-650 Example : When the tube is empty or removed, we have found 50° as the point of departure. After filling the tube 100 mm. long with urine the adjustment with homogeneous sodium light gave 53-61°; the angle of rotation, therefore, is 3-61°, and from it we can reckon for the observation tube 100 mm. long according to the above table : As concentration for 3°, 53-190 grm. As yi^- of the concentration for 6°, . . '. . 10-638 " As ^-fjy of the concentration for 1°, .... 0-177 " Amount, 64-005 grm. f Zeitschrif t f. analyt. Cliem., Band 14, Heft 3. Digitized by Microsoft® 276 ANALYSIS OF THE UBINE. In one liter of urine, therefore, there are contained 64*005 grm. of diabetic sugar. 4 Estimation op Sugae by Feementation. A. Principle. From § 25, D, 8, we know that diabetic sugar mixed with yeast undergoes vinous fermentation. One equiva- lent of diabetic sugar thereby decomposes into 2 equivalents of alcohol and 4 equivalents of carbonic acid; if we esti- mate the carbonic acid formed by the fermentation of a fixed amount of diabetic urine, we can calculate from it the quantity of sugar present. 100 parts of carbonic acid correspond to 204"o4: parts of sugar. B. Performance. In carrying out the test we use the appara- tus represented in fig. 34. 20 or 30 cc. of urine are placed in the small flask A, a little well- washed so-called dry yeast and a small amount of tartaric acid are added, and it is connected by means of the bent tube c with the small flask B, which is half filled with concentrated sulphuric acid. The tube a of the small flask A is closed at the top by a little ball of wax, 6, and the apparatus is then weighed. It is next exposed to a temperature of about 30° or 40° C, when fermentation with the evolution of carbonic acid will commence directly. The bubbles of gas pass through the tube c and the sulphuric acid in the flask B, and then escape perfectly dry through the tube d, which should be connected with a small U-shaped chloride of calcium tube, so as to prevent the access of atmospheric moisture to the concentrated sulphuric acid in B. In most cases the fermentation is ■ completed in two or three days, the evolution of carbonic acid then ceases, and all of the sugar is decomposed. Then after gently warming the flask A to remove the carbonic acid which is still retained, a little air is drawn through the apparatus at the tube r^% a until there is no longer any taste of carbonic acid, and it is then The loss of weight gives us directly the amount Digitized by Microsoft® weighed again. QUANTITATIVE ESTIMATIONS. 211 of carbonic aqid formed by tlie decomposition, and from this we can easily calculate the corresponding amount of sugar, since 48-89 parts of carbonic acid correspond to exactly 100 parts of diabetic sugar. If the urine contains albumen it must be coagulated by boil- ing, since otherwise decomposition may readily occur, which, as is well known, is accompanied by the evolution of gas. By the addition of tartaric acid, according to Lehmann, other decom- positions are prevented, while at the same time the vinous fer- mentation is promoted. From the experiments of Pasteur there is no longer any doubt that in the fermentation of sugar, not only carbonic acid and alcohol, but also other substances, amyl alcohol, butyl alcohol, etc., and even succinic acid and glycerine, may be formed, so that the carbonic acid is not a perfectly accurate measure of the sugar ; this may be the reason why many chemists have always found less sugar in diabetic urine by the fermentation test than by the excellent method of Fehling. I unconditionally prefer Fehling's method. 5. QUAIJTITATIVE ESTIMATION OP SUGAE FEOM THE DiPFEEENCE IN Specific Gravity befoee and aptee Feementation. The method proposed by Eoberts, in the year 1861, of esti- mating the sugar in the urine from the difference in specific gravity before and after fermentation, has recently been sub- jected to a rigid test by Manassein,* who has established the usefulness of the procedure beyond all doubt. After the specific gravity of the original urine has been deter- mined by the picnometer or a delicate Mohr balance, with care- ful consideration of temperature, it is treated with pure washed yeast and left to ferment in a sufficiently large flask, best at a temperature of from 20° to 24° C. At the temperature above given the fermentation is usually ended in twenty-four hours ; the fluid now becomes clear and the yeast settles to the bottom. When this point is reached it is filtered, and the specific gravity of the clear fluid is once more determined with the picnometer or the Mohr balance. * Centralblatt f. d. med. Wissenschaft., 1873, p. 551. Digitized by Microsoft® 278 ANALYSIS OF THE URINE. For a difference of O'OOl in the specific gravity before and after fermentation we reckon 0'219 per cent, of sugar. If a urine before fermentation, therefore, had a specific gravity of 1'0298, and after it one of 1"0055, the amount of sugar would be calcu- lated for the difference of 0'0243 at 0-0243 X 0-219 „ „„ , O^OOi =5-32 per cent. Or the difference of the specific gravities is multiplied by 1000 and divided by the factor 4-56, which would be obtained by multiplying the difference of the specific gravities by 1000 and dividing this product by the per cent, of sugar found with the polarizer. According to this the amount of sugar for a differ- ence in the specific gravities of 0-0243 is reckoned at 0-0243x1000 . „„ , i-— =5-33 per cent. 4:-o6 From a number of estimates which I have made the above method is by no means inferior in point of accuracy to others. That it requires at least twenty-four hours time and that yeast is not always at hand in the laboratory are disadvantages which it has in common with the methods hitherto used for estimating the sugar by fermentation. §71. 1. Estimation op Iodine by the Method op Kebsting.* A. Primiph. The method of estimating iodine depends simply on the fact that all of the iodine is separated from even a tolerably dilute solution of a metallic iodide by distillation with sulphuric acid, so that no more traces of iodine can be detected in the residue if the distillation is continued suffi- ciently long. The iodine is estimated in the distillate by a standard solution of chloride of palladium. If a solution of a metallic iodide is mixed with an excess of a solution of the chloride of palladium and a little hydrochloric acid at from 60° to 100°, the iodide of palladium formed separates on shaking after a few seconds in black caseous flakes and the supernatant fluid appears perfectly clear and colorless. If, on the other *Aniial. d. Chem. u. Pliann., Band 87, p. 31. Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 279 hand, tlie iodide solution is present in excess, the precipitation takes place much more slowly and the palladium iodide deposits partly on the sides of the glass as a black coating. For these reasons, therefore, in the estimaition of iodine we do not add the solution of palladium to that of the iodine, but we measure off a fixed volume of the latter and determine the amount of the fluid to be tested for iodine which is just sufficient to precipi- tate a definite amount of palladium solution. Since the mixture becomes almost absolutely clear on heating and shaking, and since in the second place -^-^ to -^^^-^ mgrm. of iodine may be detected by palladium, and conversely yiroVoT mgrm. of palla- dium may be distinctly recognized by means of iodine by the occurrence of a brown color, the estimations appear to be very accurate according to my own experiments performed with pure solutions of iodide of potassium and palladium chloride, both of known strength. B. Preparation of the Solutions. 1. Sta7idard Solution of Iodide of Potassium. The solution of iodide of potassium must contain exactly xtsVtt of iodine, and is, therefore, readily obtained by weighing off 1'308 grm. of pure ignited iodide of potassium, free from iodate of potassium, dissolving and diluting it to a liter. 1 cc. of this solution contains then 1 mgrm. of iodine, since 1"308 grm. of iodide of potassium exactly correspond to 1 grm. of iodine (127: 166-11 = 1: a; =1-308). This solution of iodine is used for standardizing the solution of chloride of palladium. 2. Acid Solution of Chloride of PaUadium. a. Dissolving the Palladium. The palladium solution is prepared from the metal. For example, 1 grm. is weighed off, dissolved in hot aqua regia, evaporated to dryness at 100°, then fifty parts of concentrated hydrochloric acid are added and diluted with water to 2,000 cc. Since, however, commercial palladium is probably seldom pure, the true strength of this solution must be ascertained, for which purpose the iodide of potassium solution 1 may be used, which contains TcrnT o^ iodine. b. Titration of the Palladium Solution. 10 cc. of the palladium solution to be tested are put into a small flask of about 100 or 200 cc. capacity, the glass is stop- Digitized by Microsoft® 280 ANALYSIS OF THE UBINE. pered, and heated on the water bath to 60° or 100°. The iodine solution 1 is now gradually added from a pipette or burette, it is vigorously shaken and heated a few seconds. A small amount of the fluid, which becomes clear in a few minutes, is poured into two small, narrow test tubes, so that both contain about one or two inches of fluid. A few drops of the iodine solution are then added to one tube and compared with the other to see whether a brown color is produced or not. If the former is the case, the specimens are washed into the original fluid, more iodine solution is added, it is shaken, heated, again tested in the manner indicated, and the process continued until a new amount of iodine produces no further color. When this point is attained a little fluid is filtered off, and if it is not perceptibly browned either by palladium or by the iodine solution, it can con- tain scarcely ttttoT) oi of an excess of these substances. Although this process appears difficult and tedious, it may be easily and accurately performed in at most ten minutes. We calculate the amount of palladium in the solution of palladium chloride from the number of cc. of the iodine solution used. 1 cc. of the iodine solution contains 1 mgrm. of iodine, and this corresponds to 042 mgrm. of palladium (127: 53-3 = 1 :a; =042). For example, if we have used 11 "9 cc. of the iodine solution to precipitate 10 cc. of the palladium solution, they correspond, since they contain exactly 11-9 mgrm. of iodine, to 11-9 x 042 mgrm. of palladium. 10 cc. of the palladium solution con- tain, therefore, 4-998 mgrm. of palladium, and require of an iodine solution of unknown strength a volume in which exactly 11-9 mgrm. of iodine are contained, from which the amount of iodine in the whole fluid may be readily calculated. C. Performance of the Analysis with Urine. In order to determine the amount of iodine present in urine which contains it, it is first necessary to separate it by distilling with sulphuric acid. The distilling apparatus represented in fig. 35 may be used for this purpose : « is a flask of about 300 cc. capacity, it is connected by a bent glass tube with the Lie- big's condenser, cc, in which the vapors are condensed, and the distillate is collected in the small glass d, which serves as a re- ceiver. If the quantity of iodine in the urine is at all consid- erable, 50 or 100 cc. are measured off with a pipette into the Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 281 Fig. 35. flask a, which is placed in cold water, and then, while carefully aToiding too great a heat, 20 cc. of concentrated chemically pure (particularly that which is free from iodine) sulphuric acid is added drop by drop. The flask is then connected with the condenser and the fluid is distilled until white fumes of sulphuric acid appear in the neck. If the urine contains but little iodine, however, a measured amount, about 200 or 250 cc, is supersaturated with liquor potassii, and distilled until from 20 to 40 cc. remain. This distillate contains no iodine. Observing the pre- _ _ caution given above, 20 cc. of ~^ concentrated sulphuric acid are then poured on to the cooled residue in the flask, and the distillation is completed as before, that is, until the sulphuric acid begins to vaporize. The distillate thus obtained in both cases contains hydriodic acid, all of the volatile acids of the urine, carbonic acid, sul- phurous and sulphuric acids. Before it can be used for esti- mating the iodine, the sulphurous acid must be oxidized and removed. This is readily accomplished as follows : The distil- late obtained is treated with one or two drops of starch paste (one part of starch, -^g of sulphuric acid, and twenty-four parts of water), then a saturated solution of calcic hypochlorite is dropped into it untU the fluid just, begins to become blue, and the blue color is again driven away by one or two drops of weak sulphurous acid water. The distillate is now ready for estimating the iodine ; after the whole volume has been deter- mined, which, therefore, corresponds to the amount of urine taken, it is poured into a Mohr's pipette, exactly 10 cc. of the standard solution of palladium are measured off, put into a glass, heated on the water bath, the urine-distillate containing iodine is then added, and the analysis performed exactly as be- fore, according to B, 2, b. If, for example, we have obtained 96 cc. of distillate from Digitized by Microsoft® 2g2 ANALYSIS OF TEE UBINE. 100 cc. of urine, and have used 12 cc. of it to completely pre- cipitate the 10 cc. of palladium solution which contains 4-998 mgrm., these 12 cc. contain 11-9 mgrm. of iodine (53-3 : 127 = 4-998 : x). (See B, 2, b.) In the 96 cc. of distillate, therefore, corresponding to 100 cc. of urine, there are 8 x 11-9 = 95-2 mgrm. of iodine (0-0952 grm.). 2. Hilgeb's Method. While Kersting always obtained excellent results with the method described, Hilger* states that according to his experi- ments Kersting's method constantly yields too small results. Hilger, therefore, recommends the following as the simplest method for estimating iodine quantitatively : 10 or 20 cc. of the palladium solution, according to the amount of iodine present in the urine to be tested, which is easily approximately determined by a qualitative test for iodine, are heated on the water bath in a glass vessel with a ground-glass stopper, and the urine containing iodine, first acidulated with hydrochloric acid and brought to a fixed volume, is added until all of the palladium is separated as iodide. The separation is very much hastened by violently shaking the mixture. Small amounts filtered off from time to time and treated with a few drops of the urine, on being heated indicate by becoming cloudy or remaining clear whether the reaction is finished or not. According to Hilger's observations the end of the reaction co- incides with the moment at which the separation of the iodide of palladium in distinct fiocculi commences, when the fluid is kept constantly boiling. According to numerous experiments carried out by Hilger, the urine to be examined can, therefore, be directly used for estimating the iodine after it has been previously acidulated with hydrochloric acid. He also states that the removal of sulphuric acid, phosphoric acid, and other constituents of the urine is not necessary before performing the analysis. *Zeitsclirift f. analyt Chem., Band 13, p. 343, u. Band 13, p. 475. Digitized by Microsoft® quantitative estimations. 283 3. colobimetbic estimation op lodine by the method of h. Steute.* A. Principle. If a solution of iodide of potassium of known strength is prepared, and equal amounts of bisulphide of car- bon are added to different quantities of the solution, and then a few drops of red fuming nitric acid are added, it is well known that all of the iodine is set free, and, after shaking, is taken up by the bisulphide of carbon. A scale of colored fluids contain- ing known amounts of iodine is thus obtained, with which the shades of color obtained in the estimation of iodine in the urine are compared. B. Preparation of the Color Scale. Struve used a solution of 1 grm. of iodide of potassium in 1,000 cc. of water : 1 cc. of it, therefore, contains O'OOl grm. KI or O'O0O76 grm. of iodine. The burette used was such that 21 drops from it corre- sponded to 1 cc. 5 cc. of bisulphide of carbon are used with each test. If, then, the iodine is set free by a few drops of fuming nitric acid, and by shaking transferred to the bisul- phide of carbon, the acid is removed by decanting with dis- tilled water, and we thus obtain under a layer of pure water equal quantities of bisulphide of carbon, which are colored by different but definite quantities of iodine. All of these normal solutions, under a thin layer of water, are then sealed in glass tubes of pure white glass, which have a length of 15 cm. and an internal diameter of 8 mm. If the tubes are absolutely clean, more especially if they are free from organic matters, they retain the different shades of color for a long time without marked change if they are protected from direct sunlight and if the tubes are preserved in a cool, dark place. In estimating iodine in the urine, the colored bisulphide of carbon which results is poured into a tube, which has the same dimensions as those containing the normal solutions, and the color is compared with the scale, which is best accomplished on a background of white paper with reflected light. * Joum. f. pr. Caiem., Band 105, p. 429. Zeitschrift f. analyt. Chem., Band 8, p. 230. Digitized by Microsoft® 284 ANALYSIS OF THE UBINE. Struve used the following scale : NUMBEE OF BEOPS OF THE NOEMAL KI IODIDE OF POTASSIUM. IODINE. SOLUTION. 1 > 0-000048 0-000036 3 0-000096 0-000073 3 0-000144 0-000108 4 0-000192 0-000144 6 0-000388 0-000316 8 0-000384 0-000388 10 0-000480 0-000360 12 0-000576 0-000433 14 0-000673 0-000504 18 0-000864 0-000648 31 0-001000 0-000756 30 0-001440 0-001080 C. Performance. 20 cc. of water as cold as possible are poured into a pyriforni flask of 50 cc. capacity and provided with a tightly fitting glass stopper ; 1 cc. of the urine to be examined is then added, and afterward 5 cc. of bisulphide of carbon. The contents is gently shaken, and then a few drops of fum- ing nitric acid are added to the mixture from a small pipette. If it is now shaken and then left at rest, the bisulphide of carbon quickly collects on the bottom. The stopper is care- fully raised, the glass filled with water as cold as possible, it is shaken, allowed to settle, and the acid water drawn off with a small siphon. The bisulphide of carbon is thus washed two or three times with water, when the colored bisulphide of carbon may be poured into a small previously-prepared glass tube for the comparison. But, if it has been necessary to use a large quantity of urine for the experiment, for exam- ple, 10 or 100 cc, it must first be evaporated nearly to dry- ness on the water bath after the addition of potassic hydrate, a concentrated solution of chloride of ammonium must be added to the dark-brown residue, and the whole heated until the fluid has a neutral reaction and no longer smells of am- Digitized by Microsoft® q TJ AN TIT A TIYE E8TIMA TIONS. 285 monia. When this point is reached, the cooled fluid is put into a flask, and the separation and estimation of the iodine carried out as indicated above. If, however, the bisulphide of carbon should not separate as a coherent mass, which indeed would scarcely happen, it is only necessary to evaporate the fixed volume of urine to dryness on the water bath, after add- ing the potassic hydrate, ignite the residue, extract with water, and test the filtered solution thus obtained, as recommended above, after it has been neutralized by boiling with chloride of ammonium. § 72. Estimation of Iron. A. Principle. If a solution of permanganate of potassium is added to the solution of a ferrous salt which contains an excess of hydrochloric acid, the ferrous oxide becomes oxidized, and the permanganate of potassium, on the other hand, is reduced to manganous chloride. One equivalent of permanganate of potassium (KO,MnjO,) yields five equivalents of oxygen, and thereby converts ten equivalents of ferrous oxide to ferric. If now the strength of the permanganate of potassium solution is known, an unknown amount of iron, which, of course, must be in solution as ferrous oxide, can be easily determined by ascer- taining the volume which is just sufficient to complete the oxi- dation. The end point of the experiment is very beautifully and distinctly shown, by the bright-red color which is imparted to the whole fluid by the first drop of permanganate of potas- sium solution in excess. B. Preparation of the Solutions. 1. Solution of Permanganate of Potassium. This is prepared by dissolving chemically pure permanga- nate of potassium in distilled water. The strength of the permanganate of potassium solution must be determined anew before each series of experiments, since it gradually changes even with the most careful preserva- tion. This estimation is performed in the most simple manner with a solution of ferrocyanide of potassium, ten equivalents of which are changed by one equivalent of permanganic acid into five equivalents of ferricyanide of potassium. One equivalent of ferrocyanide of potassium (211-2) corresponds to one equiva- lent of Fe (28.) Digitized by Microsoft® 286 ANALYSIS OF THE VBINE. 2. Solution of Ferrocyanide of Potassium. 7 '543 grm. of perfectly pure, dry, crystallized ferrocyanide of potassium, corresponding to 1 grm. of iron, are dissolved in water and the solution diluted to a liter. 10 cc. of this solu- tion then correspond to exactly O'OIO grm. of iron. The solu- tion is to be kept in a well-stopped bottle. Titration of the Permanganate of Potassium Solution. 100 cc. of the ferrocyanide of potassium solution (correspond- ing to 10 mgrm. of iron) are measured off with a pipette, di- luted with about 50 cc. of water, acidulated with hydrochloric acid, the vessel placed on a piece of white paper, and the dilute solution of permanganate of potassium dropped into it with constant stirring until the occurrence of a reddish-yellow color in the fluid indicates that the conversion has been completed. Supposing we have used up to this point 20 cc. of permanga- nate of potassium solution, 1 cc. will, therefore, correspond to ^j"^- = 0'5 mgrm. of iron. A second experiment must estab- lish the accuracy. An oxalic acid solution which contains 1"125 grm. of crystallized oxalic acid in the liter, corresponding to 1 grm. of iron, may be used for the same purpose. In testing, 10 cc. of this solution, corresponding to O'OIO grm. of iron, are heated almost to boiling, a little dilute sulphuric acid is added, and it is titrated with the permanganate of potassium solution until it becomes red. The volume used up to this point cor- responds to 0-010 grm. of iron. I prefer the latter method. C. Performance. In order to ascertain the amount of iron in the urine by this method, it is necessary to evaporate it and ignite the organic matters. 100 cc. of urine, therefore, are evaporated to dryness in a platinum dish and the ash is ob- tained exactly according to § 60. After cooling, the saline mass is dissolved in hydrochloric acid, heated, water is added, and the solution is carefully transferred to a flask of 100 or 150 cc. capacity. Before the titration can be undertaker, the iron present as oxide must be reduced; a little sulphite of sodium is, therefore, added to the hydrochloric acid solution, and it is boiled until the fluid has become colorless and no more trace of sulphurous acid can be detected. When we have established the strength of the permanganate of potas- sium solution by means of the oxalic acid or ferrocyanide of potassium, the solution of iron is diluted to about 60 cc. ; it Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 287 is allowed to become completely cool, the glass is placed on a piece of white paper, and the permanganate of potassium solu- tion is dropped into it with constant stirring, until the fluid has assumed a faint rose-red color. Granted that 1 cc. of our so- lution of permanganate of potassium corresponded to 0'0005 grm. of iron, and that we have used 3 cc. up to the commence- ment of the end reaction, the 100 cc. of urine, therefore, con- tained 3 X 0"5 mgrm. of iron = 0"0015 grm,. The amount of iron found, multiplied by 1'43 gives the corresponding amount of ferric oxide; multiplied by 1"286 it gives the corresponding amount of ferrous oxide. The method is a 'good one, and gives accurate results. It must be remembered that the red color produced by the last drop disappears after a time, and we must not allow it to lead us into error. § 73. Estimation op Ubic Acid. 1. By Precipitating with Hydrochloric Acid. 200 cc. of urine are put into a small beaker, 5 cc. of pure hydrochloric acid (sp. gr. = lH) are added and the mixture thoroughly stirred with a glass rod ; the beaker is then covered with a glass plate and allowed to stand at rest in a cool place with the temperature as low as possible for twenty-four or thirty-six hours. At the end of this time the uric acid will be found to have separated in crystals more or less colored, which are to be collected and washed on a weighed filter and subsequently dried. But since papes is a very hygroscopic material, the weight of a dried filter cannot be determined directly. In this case, therefore, as in all others where bodies are to be collected on weighed filters and estimated, we make use of a simple con- trivance and one which at the same time answers all require- ments. Two watch glasses which are ground on the edge and therefore fit each other with perfect accuracy (fig. 36, hh) are selected; these are held together by a brass clamp aa, so that the filter c lying between them is hermetically sealed. In dry- ing, the two watch glasses are placed one within the other, and with the filter lying on them are placed in the desiccator, fig. 15. "When the latter has been heated for a long time to 100°, Digitized by Microsoft® 288 ANALYSIS OF THE URINE. the watcll glasses are placed together, the clamp is slid over them, and, after cooling over sulphuric acid, fig. 16, they are weighed. The uric acid separated is collected on the filter thus dried, first by washing those crystals which are on the surface of the fluid on to it, when the rest of the urine, which in most cases is clear, can be poured off, or, more safely, drawn off with a siphon, and then the uric acid which adheres to the walls and bottom of the glass is loosened with a feather with only a little of its beard left, or, better still, by a glass rod which has a small piece of rubber tubing drawn over its end, and transferred to the filter. For rinsing the glass and washing down the uric acid the filtrate first obtained, which is already saturated with uric acid, should be used, never water, since this would dissolve no inconsiderable amounts of the separated uric acid. When at last all of the uric acid is on the filter and the acid urinary fluid has run off even to the last drop, we begin to wash with cold water until the filtrate is no longer rendered cloudy by a solution of nitrate of silver. Large amounts of water must be avoided on account of the solu- bility of the uric acid. If only a small filter, having a radius of 1 to 1\ inch, is used, then 30 cc. of water are quite sufficient for the most complete washing in most cases. When this point is reached, the filter is taken from the funnel, laid on one of the watch glasses and dried for a long time in the air bath at 100°. The uric acid is then weighed exactly as before, fig. 36. What the apparatus has gained in weight is the uric acid which was contained in 200 cc. of urine. This simple method has two sources of error. First, a certain amount of uric acid always remains in solution, and second, the uric acid separated always carries down a little coloring matter with it. However, if we accurately observe the above condi- tions and use a filter of 1 to \\ inch radius which has first been thoroughly washed with hydrochloric acid and then with water before drying and weighing, the two sources of error mentioned above nearly counterbalance each other if only 30 cc. of water have been used in washing the uric acid. (Heintz.) This amount Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 289 of water will suffice in most cases, so that no further reaction can be obtained in the filtrate with nitrate of silver ; but if for any reason a larger amount of wash water should be necessary, the two errors mentioned would no longer mutually cancel each other ; that caused by the solubility of the uric acid would pre- dominate, and, in order to counterbalance it, we must add 0'045 mgrm. to the amount of uric acid found by weighing for every cubic centimeter more than 30 of wash water which has been used. If, for example, the wash water amounts to 70 cc, we must add 40 x 0"045 mgrm. to the amount of uric acid found by weighing. If a urine in which we wish to estimate the uric acid contains albumen, we use the filtrate from the albumen coagulum which corresponds to a known volume of urine, and proceed with it as recommended above. Numerous methods have been proposed for estimating the uric acid volumetrically, but all have proved unsuitable or wholly unserviceable. Permanganic acid certainly has a very energetic action on uric acid, but we cannot titrate it with per- manganate of potassium directly in the urine, since many other substances are also destroyed by this energetic oxidizing sub- stance. There is nothing left but to first precipitate the uric acid by an acid, filter, wash, dissolve in potassic hydrate, and titrate the solution with permanganate after acidulating. It would probably be simpler and more accurate under these cir- cumstances, however, to weigh the washed and dried uric acid directly. The proposition to estimate the uric acid volumetri- cally by a solution of iodine in iodide of potassium has proved wholly impracticable.* Naunyn and Eiess t lay stress on the fact that in the estima- tion of uric acid in diabetic urine the usual method of precipi- tating with hydrochloric acid, etc., does not suffice ; they there- fore precipitate the urine with acetate of mercury, decompose the precipitate with sulphuretted hydrogen, and determine the uric acid in the filtrate obtained. *Zeitschrift f. analyt. Chem., Band 7, p. 516. f Centralbl. f. d. med. Wissensch., 1870, p. 567. Zeitschr. f. analyt. Chem., Band 9, p. 538. 19 Digitized by Microsoft® 290 ANALYSIS OF THE UBINB. 2. Estimation of Uric Acid by Salhowski's Method. Salkowski* and Malyt have proved that all of the uric acid is not precipitated from the urine by hydrochloric acid, but that under certain circumstances considerable amounts remain in solution and can be precipitated from the filtrate as_ urate of magnesium and silver and can be determined quantitatively. The method given by Salkowski for this purpose is the follow- ing : After the uric acid, preeipitable by hydrochloric acid, has been filtered off and washed, the filtrate is neutralized with ammonia and precipitated with a strong magnesia mixture con- taining ammonia. Since by this, under certain circumstances and on long standing, urate of magnesium separates, it is filtered immediately, washed, and the filtrate and wash water treated with an ammoniacal solution of nitrate of silver in excess. The precipitate which results is filtered off preferably with the aid of the Bunsen pump, and washed until the wash water not only remains clear on acidifying, but also no longer gives any chlo- rine reaction on the addition of nitrate of silver. The precipi- tate is then washed into a flask, distributed by continued and energetic shaking, and decomposed by sulphuretted hydrogen, for which a somewhat long exposure is necessary. The fluid -with the precipitate is then heated for a time, filtered, the filtrate evaporated to a small volume, strongly acidified with hydro- chloric acid, and left at rest thirty-six or forty-eight hours. The Tiric acid thus obtained is collected on a small weighed filter, washed, dried, and weighed ; it is pure with the exception of imponderable traces of sulphur. Schwanert,! however, is of the opinion that the amount of uric acid which remains in solution after precipitation with hydro- chloric acid may be readily determined by the ratio of solubility of uric acid in mixtures of hydrochloric acid and urine, as given by Voit and Zabelin § and substantiated by Schwanert, so that the above-described somewhat detailed method is superfluous. According to Voit, Zabelin, and Schwanert, in every 100 cc. of the hydrochloric urinary fluid 0'0048 grm. of uric acid remain in solution, which must be added to that found directly. *Zeitschrift f. aualyt. Chem., Band 11, p. 234. f Jahresberioht U. d. Fortscliritte d. Thierclbemie, Band 3, p. 178. :j:Annal. d. Chem. u. Pharm., Band 163, p. 153. § Annal. d. Chem. u. Pharm. , Suppl. Band 3, p. 313. Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. ggj In proof of his assertion Schwanert quotes fifteen compara- tive analyses in which the uric acid was determined according to Salkowski's method, and the amount obtained compared with that which remained dissolved in the fluid which was used, and reckoned at 0-0048 grm. for each 100 cc. According to these fifteen double analyses the amount of uric acid which can be precipitated by hydrochloric acid and the solution of nitrate of silver is almost exactly the same as the amount precipitable by hydrochloric acid alone plus 0"0048 grm. for each 100 cc. of the filtrate, etc. Salskowski * acknowledges these objections of Schwanert to his method, and grants that he by no means regards the esti- mation of uric acid by precipitation with nitrate of silver as a commendable method, but that there continues to be an urgent need of a still better procedure for estimating the uric acid. But if Salkowski considers the agreement of the numbers ob- tained by Schwanert by the silver precipitation with those cal- culated by using the correction as simply accidental, we cannot agree with him, since, with a concurrence in fifteen cases, there can scarcely be any question of simple chance. As for myself, I Used only the correction given by Schwanert for the uric acid remaining in solution after treatment with hydrochloric acid. § 74. Estimation of Keeatimn. A. Principle. Kreatinin, as is known, gives with chloride of zinc a compound of kreatinin chloride of zinc (C8H,N302ZnCl) quite readily soluble in hot water, and very insoluble in cold strong alcohol, which, according to my investigations, is emi- nently adapted for the gravimetric determination of this very important constituent of urine. 100 parts of kreatinin chloride of zinc correspond to 62"44 parts of kreatinin. One part of kreatinin chloride of zinc requires 9217 parts of alcohol of 98 per cent., and 5743 parts of alcohol of 87 per cent, to dissolve it. B. Preparation of the Chloride of Zinc Solution. Chemically pure oxide or carbonate of zinc is dissolved in pure hydrochlo- ric acid, and the solution evaporated on the water bath to a * Bericlite d. d. ohem. Qesellschaft, Band 5, p. 410. Digitized by Microsoft® 392 ANALYSIS OF THE UBINE. Tery thick syrup, until all of tlie free hydrochloric acid is com- pletely removed. The cooled residue is dissolved in quite strong alcohol and the solution diluted to 1'20 specific gravity. 0. Performance. 200 or 300 cc. of urine collected within twenty-four hours, mixed together and accurately measured, are treated with a little milk of lime until the reaction becomes al- kaline, and a dilute solution of chloride of calcium is added as long as a precipitate results. After one or two hours it is fil- tered, filtrate and wash water are evaporated to a thick syrup on the water bath as quickly as possible, and, while still warm, are mixed with 40 or 50 cc. of alcohol of 95 per cent. The mass, thoroughly mixed, is put into a small beaker, the evaporating dish is rinsed with a small amount of alcohol, and it is left in a cool place six or eight hours for the complete separation of all that is precipitable. The fluid is then filtered through as small a filter as possible ; at last, when all of it has passed through, the precipitate is collected on the filter and washed with a small amount of alcohol. If the whole filtrate amounts to much more than 60 cc. it is allowed to evaporate on a hot iron plate to 50 or 60 cc. When it has perfectly cooled, ^ cc. of the alcoholic solution of chloride of zinc is added, it is stirred for a long time, which aids the separation very much indeed, and it is then allowed to stand two or three days in a cool place, covered with a glass plate. When this time has expired, the crystalline precipitate is collected on a dry weighed filter be- tween two watch glasses (fig. 36), making use always of the mother liquor for washing it on to the filter. When all of the kreatinin chloride of zinc has been collected on the filter and is completely freed from the mother liquor, it is washed with small quantities of alcohol until the latter passes through color- less and no longer reacts for chlorine. The washing should be thorough but not uselessly long. The filter, with the kreatinin chloride of zinc, is lastly dried at 100°, and weighed between the watch glasses. 100 parts of it correspond to 62-44 parts of kreatinin. The kreatinin chloride of zinc thus obtained is a faintly yellow-colored powder, which the microscope shows to consist of yellow transparent spheres of varying size, with sharp contours. According to my estimates this product con- tains about 94 per cent, of pure kreatinin chloride of zinc, but since the precipitation, on account of the solubility of this Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 293 body, is neyer absolutely complete, we can confidently regard it as pure, and for 100 parts of it reckon 62'44 parts of krea- tinin; the two errors will tben nearly counterbalance each other. But the alcoholic extract of the urinary residue must always be allowed to stand several hours, as specified, before it is filtered and the kreatinin precipitated, in order that every- thing precipitable, especially the chloride of sodium, shall have separated, since otherwise the kreatinin chloride of zinc is fre- quently mixed with cubes of chloride of sodium, which would render the entire estimation false. I therefore advise that the kreatinin chloride of zinc, after being weighed, should be mois- tened with absolute alcohol, and finally examined microscopi- cally; it must show the forms described in § 3, C, 1, and be absolutely free from cubes of chloride of sodium. This method gives satisfactory results. With pure kreatinin 99 and 99 '2 per cent, instead of 100 were found. (Analytical Experiments.) In diabetic urine the sugar must be destroyed before the kreatinin is determined. Of the daily amount of urine 500 or 1,000 cc. are treated with fresh pure yeast and allowed to stand in a moderately warm place until the fermentation is complete. It is then precipitated with milk of lime and chloride of calcium as described, filtered, evaporated, and the residue extracted with 100 cc. of alcohol of 95 per cent. After standing several hours the alcoholic solution is filtered off, evaporated to 50 cc, and after cooling precipitated with chloride of zinc solution as above. If the microscopic examination of the weighed kreatinin chloride of zinc should show admixture with foreign substances, a quantitative estimation of the zinc is made, and from this the kreatinin present is calculated. 100 parts by weight of kreatinin chloride of zinc correspond to 224 parts by weight of zinc oxide. (Winogradoff and Gaethgens.)* § 75. Estimation op Albumen. A. Gravimetric. The quantitative estimation of albumen depends, as the qualitative recognition of it does, on its coagu- lation by heat, and that this may be complete, a most careful observance of the precautions given already in § 23 is required. *Zeitsclirift f. analyt. C!hem., Band 8, p. 100. Digitized by Microsoft® 294 ANALYSIS OF THE URINE. According to the greater or less quantity of albumen present 20, 50, or 100 cc. of the urine previously filtered are put into a correspondingly large beaker with a pipette, so that we do not get more than 0*2 or 0'3 of coagulated albumen, by which the whole estimation is very much facilitated. With concentrated urines, moreover, it is well to dilute the urine before heating. If, therefore, when there is a large amount of albumen only 20 cc. of urine are measured off, this is diluted with 80 cc. of water ; 50 cc. of urine, with 50 cc. of water, etc. If, on the contrary, the amount of albumen is so small that 100 cc. of urine do not con- tain more than 0*2 or 0'3 grm. of albumen, a further dilution is not advisable. The beaker is then heated on the water bath for half an hour ; if there is not enough free acid present, if a coarse flocculent coagulation does not occur, and if the super- natant fluid does not become completely clear, one or two drops of acetic acid are added with a glass rod and the heat is con- tinued, whereupon a coarse flocculent coagulation of the albu- men does ensue and the fluid becomes clear. An excess of acetic acid must be avoided, since a part of the albumen dis- solves in the acid again if too much has been added, and would therefore escape calculation. But, on the other hand, the urine under no conditions should have an alkaline reaction, since a soluble alkaline albuminate, which does not coagulate at all on boiling, is formed. We can treat the urine with acetic acid before heating, but in this case still more care is necessary, since, when too much acid has been added, coagulation does not take place on heat- ing. If the urine is acid, the addition of acetic acid is not really necessary, although the coarse flocculent and complete coagu- lation of the albumen is at all events very much expedited thereby. If the coagulation in thick flakes has been complete, the pre- cautions mentioned having been observed, and if the superna- tant fluid has become clear, filtration may be commenced. The fluid which stands above the coagulum is first poured on a dried folded filter, which has been weighed and moistened with water, this fluid runs through clear and quickly if the amount of albumen is not too large and the urine has been suf- ficiently diluted, so that the coagulation has been complete, when last of all the greater part of the coagulum is placed on Digitized by Microsoft® qUANTITATIVB ESTIMATION'S. 395 the filter. When all of the fluid has passed through, the albu- men is washed with hot water into the apex of the filter, which is easily accomplished. The beaker is now rinsed with hot water, the last particles of albumen are loosened with a feather and the whole is thus collected on the filter, which is then washed with hot water until the filtrate no longer gives any re- action with nitrate of silver and on being ignited leaves no resi- due on platinum foil. If the operation is performed in the man- ner I have described above, the filtration takes place very well and very rapidly, otherwise it is often very slow and tedious. The filter is now carefully removed from the funnel, placed on one of the two watch glasses, fig. 36, and dried on the water bath at 100^ until it no longer loses weight after cooling over sulphuric acid. Great care is to be exercised here, since the albumen, especially when we have too large an amount on the filter, usually cakes together into a horny mass, and, as it were, becomes covered with a dry crust, while moisture is still con- tained within it and can only be removed by very slow drying at 100° (six or eight hours). Therefore the drying operation can only be regarded as completed when two weighings agree, the filter having in the meantime been exposed to the given temperature for a considerable time. After deducting the weight of the watch glasses and of the filter from the weight last obtained, we obtain the quantity of albumen which was present, and which may then be calculated for the whole amount of urine. The estimation of albumen performed in this manner is sub- ject to two errors, for in the first place the albumen in its co- agulation carries down with it a little coloring matter, which cannot be removed even by prolonged washing with hot water. This is the reason why dried albumen in most cases appears to be yellow or even brown. However, this source of error is very inconsiderable and may be safely neglected. But frequently the earthy phosphates also separate with the albumen and naturally cause the amount of albumen to appear too great. In perfectly accurate estimations, therefore, the dried and weighed albumen, together with the filter, must be ignited in a weighed platinum crucible until all of the carbon has disap- peared, which can be easily accomplished in a short time when the crucible lies obliquely. The increase in weight of the pla- Digitized by Microsoft® 296 ANALTSia OF THE UBINE. timim crucible minus the known weight of the filter ash gives the amount of ash of the weighed albumen, which must be sub- tracted from the amount of albumen first found. In most cases this roundabout way is unnecessary ; I have repeatedly satis- fied myself that the amount of ash in albumen coagulated from a sufficiently dilute acid urine is very small and consequently has a very slight influence on the result. 20 cc. of a urine rich in albumen were diluted with 80 cc. of water, coagulated in a beaker on the water bath and the coagu- lum collected on a folded filter, thoroughly washed and dried at 100° to a constant weight. The albumen weighed 0"3573 grm., which calculated for the whole twenty-four hours' amount of urine (1,050 cc.) = 18-76 grm. After igniting and subtracting the filter ash there remained 0'0013 grm. of albumen ash. After subtracting this the twenty-four hours' amount of albumen was calculated at 18-69 grm. instead of 18-76 grm. first found. B. By Circumpolarization. If the amount of albumen in a urine is not very small, the urine itself not too dark colored, and if it becomes perfectly clear on being filtered, the albumen may be estimated also by means of the polarizing apparatus of Soleil-Ventzke. The method is exactly the same as was de- scribed in the estimation of sugar in § 70, 3. If the color and transparency of the urine permit, an observing tube 200 mm. long should be used, and after being carefully filled and placed in the apparatus, by turning the compensator the two halves of the field of the double plate are made exactly isochromatic. The zero-point of the nonius now lies on the left side of the zero-point of the scale, and each division with a tube 200 mm. long corresponds to 1 grm. of albumen in 100 cc. of urine ; and each division of the nonius to 0*1 grm. If, however, we have used a tube only 100 mm. long, the divisions of scale and nonius are to be multiplied by two in order to find the per cent, of albumen in 100 cc. of urine. If the urine does not become suf- ficiently clear by filtration alone, the turbidity may frequently be cleared up by a drop of acetic acid or a few drops of car- bonate of sodium or milk of lime without thereby changing the specific rotation of albumen. After filtration the urine is clear enough in most cases to allow of its examination in the po- larizing apparatus, in some cases, however, it fails. (Hoppe- Seyler.) Digitized by Microsoft® QTTANTITATIVE ESTIMATIONS. 297 Since, as my abundant experience has shown, the cases are very rare in which the method of determining albumen quanti- tatively described under A cannot be performed, I content my- self with merely mentioning here the other methods which have been proposed, for none of them equals in accuracy the gravi- metric, which, properly performed, gives the desired result quickly and accurately. 1. The Method of Bodeker* depends on the fact that albumen in an acetic acid solution is completely precipitated by ferrocy- anide of potassium. This procedure gives only approximate results, of which I have convinced myself several times. Also Thomas t states that if the albumen does not amount to 1"5 or 2 per cent., the results are wholly unreliable. In all cases in which the quantity of albumen was very small, Thomas found by Bodeker's method very much more albumen than by weighing. 2. Vogd's Optical MetJiod.% The urine is rendered faintly acid with acetic acid, measured amounts of 4 or 6 cc, etc., are di- luted to 100 cc. with water, heated to boiling, quickly cooled and tested by ascertaining whether the light from a stearine candle is still perceptible through a layer of the mixture 6*5 cm. thick. The experiment is repeated with different degrees of concentration until a dilution is reached at which the picture of the flame just disappears. The percentage of albumen in the urine is found by dividing the mean number 2"3553, obtained by Dragendorff by chemical analysis, by the number of cc. of urine used. Dragendorff performed thirty-five comparative analyses ; three times differences of more than O'l were shown, eleven times of more than 0'05, so that of thirty-five analyses twenty-one corresponded with the gravimetric method to with- in 0'05. Masing obtained in seven comparative analyses differ- ences up to 20 per cent., which were plus as well as minus. 3. Lang, Haehhr, and Bornhardt% calculate the amount of albu- men in the urine from the difference in the specific gravity of the urine before and after it has been coagulated by heating. According to Haebler this difference must be multiplied by 210, * Annal. d. Chem. u. Pharm., Band 111, p. 195. f Schmidt's Jahrbiicher, Band 120, p. 171. \ Zeitsckrift f. analyt. Chemie, Band 7, p. 152. Masing, Beitrage zur Albvuni- nometrie, Dorpat, 1867. § Zeitschrif t f. analyt. Chem., Band 7, p. 513, und Band 9, p. 149. Digitized by Microsoft® 298 AI^ALYSIS OF THE UBINE. * according to Bornhardt by 415, in order to find the percentage of albumen in tlie urine. My experiments show that Haebler's quotient is absolutely false, and also that Bornhardt's number yields with very careful manipulation only tolerable results when the amount of albumen in the urine is not too small, but with the low specific gravity of albumen and its small amount in the urine the limits of error are very great. Stscherlakoff and Ohomjakoff* arrived at the same results. 4. MeMs Method, f To 100 cc. of urine, which must not con- tain more than 0-2 to 04 albumen, 2 cc. of nitric acid are added, and then 10 cc. of a mixture of equal parts of crystallized car- bolic and glacial acetic acids with two parts of alcohol of 90 per cent. It is filtered, first washed with water, to which J per cent, of carbolic acid has been added, and later with water con- taining alcohol, dried at 110° C, and w-eighed. The carbolic acid precipitates the albumen without forming a chemical com- pound with it. According to examinations by Schacht,| Mehu's method, especially in urines which contain a small amount of albumen, has no sort of advantage over the one described by me. 5. Method of P. Liborius.% 50 or 100 cc. of urine are treated in a beaker with four or five times its volume of alcohol of 85 per cent. After twenty-four hours the coarse flocculent pre- cipitate is collected on a filter, washed, dried at 110° or 115° C. and weighed. The precipitate is then ignited in a weighed platinum crucible, the ash which remains, and is not inconsid- erable in quantity, is weighed, and its weight deducted from that first obtained. By this procedure Liborius always obtained more albumen than by coagulation or by the old method of Berzelius, which, moreover, yielded results agreeing with those obtained by coagulation. The reason of this is quite apparent, since alcohol not only precipitates albumen from the urine, but all albuminous bodies also, especially peptone, which, accord- ing to Senator,! is never absent from any albuminous urine, as * Zeitschrift f . analyt. Chem., Band 9, p. 537. f Journ. d. Pharm. et de Chim., 1869, p. 95. Zeitschr. f. analyt. Chem., Band 8, p. 523. X ArcUv d. Pharm. , Band 139, p. 19. § Deutsch. Archiv f. klin. Med., Band 10, p. 819. II Virchow'E Archiv, Band 60, p. 488. Digitized by Microsoft® qUANTITATIVB ESTIMATIONS. 299 well as the albuminous bodies mentioned by C. Gerliardt,* which are not identical with albumen, and lastly, uric acid, mucus, and some other substances. Therefore, we cannot let the precipitation with alcohol pass as a method of estimating albumen. 6. L. Girgensohn's Method.-f This method is founded on the fact that tannin completely precipitates albumen, and that all of the tannin can be withdrawn again from the compound of tannin and albumen by boiling with alcohol. In performing the test a definite quantity of urine is treated with half its vol- ume of a 20 per cent, solution of chloride of sodium, and then as much solution of tannin is added as is necessary for the" com- plete precipitation of the albumen. The precipitate is collected in a weighed filter, washed with distUled water until the chlo- rine reaction disappears, and then with boiling alcohol as long as any tannin can be detected in the filtrate. The residue is dried and weighed. It might be well to remoTS the uric acid first by rendering it slightly acid with acetic acid, and allowing it to stand in the cold. This method, also, is not free from the criticism which must be made of the precipitation with alcohol. Tannin by no means precipitates the albumen alone from the urine, but at the same time a number of other bodies. § 76. Calcium akd Magnesium. I. ESTIMATION OF CAICITTM:. A. Principle. The method of estimating calcium depends on the fact that all of the calcium is precipitated from an acetic acid solution of the phosphate of calcium in the form of an oxalate by oxalate of ammonium, and that oxalate of calcium is transformed by a red heat into carbonate of calcium and caustic lime, whose amount is determined by standard solutions of hy- drochloric acid and sodic hydrate. B. Preparation of the Solutions. 1. Standard SydrocMoric Add. The hydrochloric acid which is used for this estimation of * Centralblt. f. d. med. Wissenschaft., 1869, p. 174. t Deutsch. Archiv f. klin. Med., Band 11, Heft 6. Digitized by Microsoft® 300 ANALYSIS OF TEE UBINE. calciuin is best so standardized that each cc. corresponds to ex- actly 10 mgrm. of calcic oxide. One liter of the acid, therefore^ must saturate 10 grm. of calcic oxide, or 18"93 grm. of carbo- nate of sodium. To prepare such an acid we twice weigh off an accurate quantity (about 1 or 1'2 grm.) of pure carbonate of sodium, previously ignited, and dissolve each portion separately in a flask in water, heat to boiling, after the solution is treated with a few drops of tincture of litmus, and then let the dilute hydrochloric acid flow into it until the blue color of the solu- tion has changed to onion red, which does not disappear again on further boiling. (The purpose of the boiling is to remove the carbonic acid which has been set free, so that the transi- tion of the wine-red color, which is caused by the carbonic acid, into the onion red shall come out sharply.) The experiment is repeated with the second quantity of carbonate of sodium, and from the results obtained the quantity of hydrochloric acid in the liter is reckoned by taking the average of the two. If, for example, we have found that one liter of the hydrochloric acid corresponds to 414 grm. of carbonate of sodium, then 457 cc. will exactly saturate 18'93 grm. If we, therefore, measure off 457 cc. from the hydrochloric acid thus tested, and dilute it to a liter, it has the required strength. 1 cc. then corresponds to 0"0189 grm. of carbonate of sodium, or 0"010 grm. of CaO. A control experiment with carbonate of sodium must confirm the accuracy of the dilution. 2. Standard Sodic Hydrate. The sodic hydrate must exactly correspond to the hydro- chloric acid, 10 cc. of it must, therefore, exactly saturate 10 cc. of the hydrochloric acid, so that after the addition of the last drop of the 10 cc. of sodic hydrate, the red color of the hydro- chloric acid changes to a clear blue. We must be especially careful that the sodic hydrate is completely free from carbonic acid, so that the transition of color may be sharply recog- nized. 10 cc. of the hydrochloric acid are now measured off with a pipette, it is allowed to flow into a small beaker, it is colored red with a few drops of tincture of litmus, and then the sodic hydrate is added until it is a clear blue. If 8 cc. of sodic hydrate have been required to 10 cc. of hydrochloric acid, we measure off 800 cc. and dilute it to a liter. Equal volumes of the two will then accurately saturate each other. The accu- Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 301 racy of tte dilution is tested by a new experiment ; if after the last drop of the 10 cc. of sodic hydrate the red color of the 10 cc. of hydrochloric acid has become a clear blue, the sodic hydrate is fit for use in the estimation. C. Performance. Exactly 100 or 200 cc. of the urine previ- ously filtered are measured off with a pipette, allowed to flow into a beaker, and ammonia is added until an abundant precipi- tate has taken place, which is then caused to disappear by the careful addition of acetic acid. The calcium is precipitated from the acetic acid solution thus obtained, which must con- tain only a few drops of acetic acid in excess, by oxalate of ammonium, and the glass is allowed to stand covered in a warm place until the precipitate has completely settled and the supernatant fluid has become perfectly clear. In most cases after six or eight hours the fluid can be drawn off clear by a siphon, which is always to be preferred to slow filtering when it can be performed without loss. The rest of the fluid with the calcic oxalate is poured on to a small filter free from calcium and thoroughly washed with water. (Filtrate and wash water are put aside for determining the magnesium.) The filter and the precipitate, still moist, are placed in a small platinum crucible, dried and ignited antil all of the carbon is consumed. The lime, which has become partly caustic, is carefuUy rinsed into a small flask, 10 cc. of the standard hy- drochloric acid are added and cautiously warmed until the whole is dissolved and the carbonic acid is expelled. Then after the solution has been colored faintly red by two or three drops of tincture of litmus, the non-saturated part of the hydro- chloric a^d is titrated back with the sodic hydrate solution until the blue color appears. If the number of cc. of sodic hy- drate used up to this point are subtracted from the 10 cc. of hydrochloric acid added, we obtain the number of cc. satu- rated by the lime, each one of which corresponds to 10 mgrm. of calcic oxide. If then we multiply the number of cc. of hy- drochloric acid saturated by 10, we obtain directly the per- centage of lime in the urine, if 100 cc. were taken for the esti- mation. (See Analytical Experiments.) If we wish to calculate the lime found as phosphate, 1 cc. of the hydrochloric acid cor- responds to 18-45 mgrm. of SOaOPOj. Gravimetric Estimation. We proceed as above by precipi- Digitized by Microsoft® 302 ANALYSia OF THE USmK tating the calcium in the form of oxalate from 200 cc. of urine made acid with acetic acid. The washed and dried calcic oxa- late, freed from the filter, is then placed in a weighed platinum crucible and ignited for a considerable time after the filter has been completely reduced to ashes on the cover. After cooling the crucible, the calcium, which has become partially caustic during the ignition, is moistened with a few drops of pure dilute sulphuric acid, when a loss may easily occur, and, therefore, the crucible must be covered as closely as possible during the operation. After heating a second time the calcium remains behind as a sulphate ; the crucible is allowed to cool over sulphuric acid and is weighed. After subtracting the weight of the crucible and filter ash we obtain the amount of sulphate of calcium from which the corresponding amount of phosphate of calcium is reckoned. More easy still than evapo- rating and heating to a red heat with sulphuric acid is the conversion of the calcic oxalate into sulphate by pure ammo- nium sulphate. (Schrotter.) Three equivalents of sulphate of calcium correspond to one equivalent of phosphate of calcium, having the composition SCaOjPOj. If, therefore, we multiply the amount of sulphate of calcium obtained by ^f f = 0-7598, we obtain the corresponding amount of phosphate of calcium. If, on the other hand, we wish to reckon the sulphate of calcium as CaO, we must multi- ply the amount found by 04118. n. ESTIMATION? OV THE MAGNESITIM. 1. By Weighing. The fluid filtered from the calcic oxalate is treated with ammonia until the reaction is alkaline, by which all of the magnesium is precipitated as ammonio-magnesian phos- phate. When the precipitate has completely settled after a few hours, it is collected on a filter, the weight of whose ash is known, washed thoroughly with water, to which ^ of its volume of ammonia has been added, and dried. When this is accomplished, the precipitate is separated as completely as possible from the filter, it is put into a weighed platinum cru- cible, the filter is folded, and a thin platinum wire wound round it spirally, and it is ignited in the upper cone of the flame, which abounds in oxygen. This operation with phosphate of magnesium, otherwise so wearisome, is rendered very much Digitized by Microsoft® QVANTITATIVE ESTIMATIONS. 303 easier and shorter by this procedure ; the ash becomes pure and ■white after a very short time. When the ignition has been accomplished the filter ash is added to the precipitate, the cover is placed on the crucible and it is heated a long time, at first very gently, but at last at the strongest red heat, with the cover off; it is then allowed to cool over sulphuric acid and weighed. The ammonio-magnesian phosphate precipi- tated from the urine in this way is, however, always mixed with organic matters, especially uric acid, which on heating yield a carbon difficult to ignite, and which, therefore, renders a very long-contuiued ignition of the precipitate necessary and with the crucible uncovered. It is, therefore, best to place a small piece of nitrate of ammonium on the ammonio-magne- sian phosphate in the crucible after the filter has been ignited in the manner described, moisten it with a drop of water, dry, and heat first very gently, and lastly to a powerful red heat. The charcoal completely disappears, and we obtain the phosphate of magnesium very readily in this manner of daz- zling whiteness. The ammonio-magnesian phosphate becomes pyrophosphate of magnesium (^MgOjPOj) on ignition; after subtracting the weight of the crucible and the filter ash an amount remains behind which, added to the quantity of pyro- phate of calcium calculated and found, gives the v/hole amount of earthy phosphates (phosphates of calcium and magnesium) in the urine taken. If, however, we wish to calculate the pure phosphate of magnesium found (3MgO, PO5) as pure oxide (MgO), we must multiply the amount obtained by ^^, that is = 0-3604, since 111 parts of pyrophosphate of magnesium correspond to 40 of pure magnesic oxide. The earthy phosphates are determined more accurately and quickly in two amounts of urine, as follows : a. The amount of phosphate of calcium (SCaOjPOs) in 200 cc. of filtered urine is accurately determined according to the method given in § 76, i. C. Each cc. of hydrochloric acid satu- rated corresponds to 18*45 mgrm. of phosphate of calcium. b. Another 200 cc. of the filtered urine are precipitated with ammonia and allowed to stand six or twelve hours to completely separate and deposit all of the earthy phosphates. The fluid is then drawn off with a siphon, as far as this can be done without loss ; the precipitate is collected on a filter, the Digitized by Microsoft® 304 ANALYSIS OF THE UBINE. weight of whose ash is known, it is washed with water con- taining ammonia (three parts of water and one part of ammo- nia), and the magnesium estimated exactly as was indicated in § 76, n. 1. This second estimation giTes the whole amount of earthy phosphates (2MgO,POs + 30aO,PO5) contained in the urine. If we subtract the phosphate of calcium found in 1 from it, the remainder is the amount of phosphate of magne- sium in the urine. 2. Volumetricatly. The magnesium is precipitated from 200 cc. of urine by ammonia, after the calcium has been removed by oxalate of ammonium ; the ammonio-magnesian phosphate is collected on a small filter after a few hours and washed with water containing ammonia. The filter is then broken through with a glass rod, the precipitate washed into a beaker and dis- solved with acetic acid. (If a little uric acid remains behind here, as has repeatedly happened in my analyses, the solution is best filtered from it.) The phosphoric acid is then determined in the fluid obtained exactly according to § 67, C, b. The amount of phosphoric acid found multiplied by 0"563 gives the corre- sponding amount of pure magnesia (MgO) ; on the other hand, multiplied by 1'563 it gives the corresponding quantity of pyro- phosphate of magnesium. III. INDIEBCT ESTIMATION OF CALCIC AND MAGNESIC PHOSPHATES. As is known there is no true separation attained by indirect analyses, but ulterior circumstances are brought about, from which we can calculate the acids and bases found together. If, for example, we have to determine potassium and sodium, the analysis can be made in such a manner that the two are changed into sulphates ; if these are weighed and the whole amount of sulphuric acid in them determined, the amounts of potassium and sodium can be calculated from these data. This is the case with the calcium and magnesium contained in the urine in combination with phosphoric acid. To perform this estima- tion we precipitate the earthy phosphates in two specimens of 200 cc. of filtered urine by means of ammonia, filter it after a few hours, and determine one amount gravimetrically according to § 76, n. 1. The second amount is washed into a beaker, dissolved in acetic acid, and the phosphoric acid in it titrated Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 305 exactly according to § 67, C, b. The result is calculated for the twenty-four hours' amount of urine. We now know : a. The amount of the earthy phosphates (MgO),,PO. [in twenty-four hours. b. The amount of phosphoric acid for twenty-four hours cor- responding to the calcium and magnesium. An example will now explain the calculation in the simplest and clearest manner. Let us assume that the above estimations had shown that a daily amount of urine contained 1 grm. of earthy phosphates, and the phosphoric acid combined with the earths amounted to 0"579 grm. The amounts of calcic and magnesic phosphates are reckoned as follows : If all the PO5 were combined with calcium, the earthy phosphates should weigh 1'264 grm., according to the following proportion : 71 : 155 = 0-579 : x. (PO5) [(CaO)3,P05] (amount of PO5 found.) a;=l-264 grm. Since the total earthy phosphates, however, weigh less (grm. 1), phosphate of magnesium is also present in an amount proportional to the difEerence. 1-364- 1-000 = 0-264. This quantity of magnesiau-phosphate is obtained from the fol- lowing proportion : The difEerence between the equivalents of phosphate of calcium' (155) and phosphate of magnesium (111), that is 44, is to the equivalent of phosphate of magnesium (111), as the difEerence found, 0-264, is to the phosphate of magnesium present. 44 : 111=0-264 : x. a;=0-666 grm. (MgO)2,P05. We have then the total earthy phosphates =1-000 grm. The calculated amount of phosphate of magnesium =0 -666 " Leaving (OaO)3,P05 =0.334 grm. 30 Digitized by Microsoft® 306 AlfALTSIS OF THE UBINE. From this consideration tlie following short, universally ap- plicable method of calculation may be deduced : The amount of phosphoric acid in the mixture is multiplied by 2-1831, from the product the amount of the earthy phosphates is subtracted, the remainder is multiplied by 2-5337, and the product is the amount of the phosphate of magnesium contained in the mixture. If we designate the amount of the earthy phosphates found by S, and the PO5 obtained by P, the calculation may be simply expressed by the following formula : (P. 3-1831-S) 2-5327. If we wish to calculate the calcium and magnesium in the amounts of phosphate of calcium and of magnesium obtained, the following formulae are used : (OaO)3P05 X 0-5420 = CaO. (MgO),P06 X 0-3604 = MgO. § 77. Estimation op Ammonia,. A. Principle. This method of estimating the quantity of am- monia, first mentioned by SchlOsing, depends simply on the fact that an aqueous solution containing free ammonia suffers its ammonia to escape at ordinary temperatures in a relatively short time when exposed to the air, and that dilute sulphuric acid absorbs all of the ammonia contained in a closed space. If, therefore, we place an aqueous solution of ammonia together with a measured volume of standard sulphuric acid in a closed space, all of the ammonia in a short time will have combined with the sulphuric acid and have saturated an equivalent amount of it, which may be readily ascertained by titrating back the non-saturated portion with a standard sodic hydrate solution. B. Preparation of the Solutions. 1. Standard Sulphuric Acid. 14 grm. of hydrated sulphuric acid are diluted with 200 grm. of water, and when the mixture has become cool the strength of this dilute acid is determined in the usual way by precipi- tating two specimens of 10 cc. each with chloride of barium. If the two analyses agree we accept the result as correct. If, for example, we find that 10 cc. of the dilute acid contain 0-505 grm. of sulphuric acid, then they will be exactly saturated by Digitized by Microsoft® qXTANTlTATIVE ESTIMATIONS. 307 0"2146 grm. of ammonia (NH3); therefore, 1 cc. of the dilute acid corresponds to 0'02146 grm. of ammonia (NH3). 2. Standard Sodic Hydrate Solution. ' We determine how large a volume of a good sodic hydrate so- lution, free from carbonic acid, is required to saturate 10 cc. of the standard sulphuric acid. For this purpose 10 cc. of the standard sulphuric acid are put in a small beaker, a few drops of tincture of litmus are added, and the sodic hydrate solution dropped from a pipette until the fluid just becomes blue. If we have used 30 cc. of the sodic hydrate solution up to this point, we know that each cc. of it corresponds to 0'00715 grm. of ammonia, because 10 cc. of the sulphuric acid (correspond- ing to 0"2146 grm. of NH3) have been exactly saturated by 30 cc. of the sodic hydrate solution. C. Process. A flat glass or porcelain vessel (a beaker broken off an inch from the bottom is suitable for the purpose) is placed on a plate of ground glass which is smeared with tallow, and 10, or better, 20 cc. of the urine which is to be tested, freed from mucus by filtration, are introduced into it. A tri- angle made of glass rod is then laid on the vessel, and on the triangle a flat dish with low sides containing 10 cc. of the standard sulphuric acid is placed. A bell glass with a ground edge and smeared with tallow is then placed over the whole apparatus, so that an hermetically closed space is thus obtained. Fig. 87 shows the whole ap- paratus. When the appara- tus is all prepared, the bell glass is raised, a sufficient quantity of milk of lime (10 cc.) is added to the urine from a pipette not drawn out at the end, and the bell glass is immediately firmly replaced. After forty-eight hours the whole of the ammonia has been expelled from the 10 or 20 cc. of urine and absorbed by the sulphuric acid. If the non-saturated sulphuric acid is titrated back with the sodic hydrate solution, we ascertain the amount saturated by the am- PiG. 37. Digitized by Microsoft® 308 ANALTSI8 OF THE URINE. monia, and consequently the quantity of ammonia in the 20 cc. of urine. Example : 10 cc. of sulphuric acid = 0.505 grm. SO3 = 0-2146 grm. NHg. They require 30 cc. of sodic hydrate solution ; 1 cc. of sodic hydrate solution, therefore, corresponds to -^4^" = 0-00715 grm. of NH,. At the end of the experiment 26 cc. of the sodic hydrate solution have been required in titrating back. Therefore, an amount of NH3 has been evolved which corresponds to 4 cc. of the sodic hydrate solution. The 20 cc. of urine, therefore, contain 4 x 0-00715 = 0-0286 grm. NH3 = 1-43 NH, per thousand. From my own experiments it appears that perfectly normal fresh urine does not undergo the alkaline fermentation in forty- eight hours ; but these experiments must not be taken as the rule in all cases, since many urines, as we well know, very soon become alkaline. I consider it safer, therefore, to make a con- trol experiment, in addition to the regular estimation of ammo- nia, by placing a like amount of the same urine in a second apparatus without milk of lime and observing the result. If we find that the urine readily becomes decomposed, it is better to first remove the coloring and extractive matters. We pre- pare for this purpose a mixture of acetate and basic acetate of lead solutions, an equal volume of each, measure off 30 cc. of the urine, add to it an equal quantity of the lead solution, filter, and take 40 cc. from the clear filtrate corresponding to 20 cc. of urine for the estimation of the ammonia. This precaution is quite unnecessary with a normal fresh urine, as my experi- ments show.* This method gives very satisfactory results. (Analytical Experiments.) § 78. Estimation of the Ammonia and Potash by means op Platinic Chloeide. A measured quantity of urine, 20 or 30 cc, are placed in a beaker, and a sufficient quantity of platinic chloride and three times its volume of a mixture of alcohol and ether are added. After twenty-four or thirty-six hours, when no further precipi- * Joum. f. pract. Chemie, Band 64, p. 177. Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 309 tation is seen to take place, it is filtered, well washed with alcohol to which a little ether has been added, and dried. The precipitate, together with the filter, is then placed in a platinum crucible and ignited, the crucible being covered at first, until the carbon of the filter is wholly consumed, which process may be very much hastened by giving the crucible an oblique position. The remaining mass is then treated with hot dilute hydrochloric acid as long as the acid takes up anything; the platinum which remains behind is placed on a filter, the weight of whose ash is known, carefully washed with hot water, and the filtrate obtained preserved for estimating the potassium by the method to be mentioned directly. After ig- niting and weighing, by subtracting the weight of the filter ash and crucible, we obtain the quantity of platinum which cor- responds to the amount of ammonia and potassium contained together in the urine. In order now to determine the quantity of the potassium, the hydrochloric acid solution, together with the wash water which contains the whole of the potassium, is reduced to a smaU volume (1 or 2 cc.) by evaporation, it is precipitated by thirty drops of platinic chloride solution and a mixture of alcohol and ether as mentioned above. After twenty-four hours the precipitate which is obtained, and which contains all of the potassium as potassio-platinic chloride, is placed on a filter, washed with alcohol and ether, dried, ignited with the filter as above, extracted with hydrochloric acid, the remaining plati- num collected on a filter, the weight of whose ash is known, dried, ignited, and weighed. After subtracting the weight of the filter ash, we obtain the quantity of platinum which corre- sponds to the potassium. The difference between this amount of platinum and that obtained at first corresponds to the quan- tity of ammonium. If, for example, we find the whole amount of platinum to be 0'1980 grm. for the potassium and ammonium contained in 30 cc. of urine, and for the potassium alone by the second estimation 0-1330, there remains for ammonia 0'065 grm. of platinum (0-1^80-01330). One hundred parts of platinum correspond to 17"182 parts of ammonia, therefore 0'065 platinum (100 :17'182 = 0'065:a;) x =. 0*01116 ammonia in 30 cc. of urine. We calculate in the same way the amount of potassium pres- Digitized by Microsoft® 310 ANALYSIS OF THE URINE. ent from the amount of platinum employed in separating it; 100 parts of platinum correspond to 47 '61 parts of potassic oxide. § 79. Estimation of the Potassium and Sodium. A. Direct Determination. 30 cc. of urine are mixed witli 30 CO. of baryta solution (two volumes of baryta water and one volume of a cold saturated solution of nitrate of barium, see § 65, B, 3), /it is allowed to stand for a time, filtered, 40 cc. of the filtrate are measured off, corresponding to 20 cc. of urine, and evaporated to dryness in a platinum capsule on the water bath. The residue is then heated over a free flame, at first very gently to avoid decrepitation and too sudden combustion, af- terward strongly, and the heat is continued until the greater part of the carbon has been consumed. Yet we must guard against too strong a heat lest a part of the chlorides should volatilize. The residual mass is then extracted with hot water, acidulated with hydrochloric acid, and treated, without previous filtration, with a solution of ammonia and carbonate of ammo- nium as long as a precipitate is thrown down, it is filtered, the precipitate thoroughly washed, and the filtrate, after acidulating with hydrochloric acid, is evaporated again to dryness in the platinum capsule. After the residue has become perfectly dry it is carefully heated to drive off the ammonium salts, but in such a manner as not to suffer any loss from decrepitation, the residue is again dissolved in a little water, a few drops of ammo- nia and carbonate of ammonium are again added, the mixture • filtered,^ the precipitate carefully washed and the filtrate again evaporated to dryness, but this time in a previously weighed platinum capsule. The thoroughly dry residue is gently heated to drive off the ammonium salts, it is then left to cool in the desiccator and weighed. We thus obtain the whole quantity of potassium and sodium in the form of chlorides. To separate the two the weighed amount of alkaline chlorides is dissolved in a little water, chloride of platinum added in considerable excess, and the mixture evaporated almost to dryness on the water bath. The residue is then treated with alcohol of 80 per cent, and allowed to stand several hours with frequent stirring. When the sodio-platinic chloride is dissolved, and the superna- tant fluid has a deep yellow color, a sign that sufficient chloride of platinum has been added, the potassio-platinic chloride is Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 311 collected on a filter whicli has previously been dried at 100° 0. and weighed, washed with alcohol, dried at 100° 0. and weighed. From the potassic-platinic chloride obtained the correspond- ing amount of chloride of potassium is calculated (100 parts of potassio-platinic chloride correspond to 30 '51 parts of chloride of potassium), and this subtracted from the whole quantity of the alkaline chlorides gives as the difference the amount of chloride of sodium. The amount of chloride of potassium obtained gives when multiplied by 0"6317 the corresponding amount of potassic ox- ide ; the chloride of sodium multiplied by 0'5302 gives the cor- responding amount of sodic oxide. B. Indirect Determination. The potassium and sodium can be calculated indirectly, though this method is inferior to the former in accuracy. The principle of the indirect analysis has already been given in § 76, in. After the whole quantity of chloride of potassium and chloride of sodium has been accu- rately determined by weighing, according to A, the saline mass is dissolved in water, the solution is introduced into a beaker, the vessel thoroughly washed with water, and, after the addition of a few drops of a solution of neutral chromate of potassium, the whole amount of the chlorine is determined by means of a standard solution of nitrate of silver according to § 66. If we know the total amount of the chlorides of potassium and sodium, as well as the total amount of chlorine, the quantity of potassium and sodium can be reckoned from these data. The amount of chlorine in the mixture is multiplied by 2*1029, the amount of the metallic chlorides is subtracted from the product, and the remainder is multiplied by 3 "6288. We thus find the quantity of chloride of sodium contained in the saline mass, and this, subtracted from the total metallic chlo- rides, gives the quantity of chloride of potassium. Chloride of potassium x 0*6317 = potash (KO). Chloride of sodium X 0*5302 = soda (NaO). Experiments to determine the quantity of potassium by pre- cipitating the previously concentrated urine with tartaric acid did not give favorable results. On account of the impurity of the acid tartrate of potassium obtained the results were con- stantly too high. (Salkowski.)* * Pfluger's ArcMv, Band 6, p. 309. Digitized by Microsoft® 312 ANALYSIS OF THE UBINE. § 80. Estimation of the Caebonic Acid. According to Marohand,* the free carbonic acid in the urine can be estimated in the following way : About 100 cc. of the urine to be tested are placed in a glass flask which is fitted with an air-tight, doubly perforated stopper. A tube which dips into the urine and is drawn out to a fine, easily fusible point at the other end, is passed through one opening of the stopper ; while through the second opening a doubly bent tube is passed, one of whose arms enters an empty flask through an air-tight stopper. This flask is coimected by a second tube with a similarly arranged flask filled with clear baryta water, which again is connected with one or two flasks half-filled with baryta water. The last of these is connected with an air pump. When the apparatus is prepared, the urine is heated on the water bath to SO"" or 60° C. and the air slowly exhausted. The fluid soon commences to boil and to distil over into the empty flask, and the baryta solutions become cloudy from the separation of carbonate of barium. After half or three-quarters of an hour the fine point of the first tube is broken off and air is drawn through the apparatus. The precipitated carbonate of barium is carefully filtered off, and, after washing, dissolved in hydro- chloric acid, precipitated again by sulphuric acid, and weighed as sulphate of barium. From the quantity thus obtained we cal- culate the carbonic acid which was present. 116'5 parts by weight of sulphate of barium correspond tp 22 parts by weight of carbonic acid. § 81. EsTnuATioN OF the Total Nitbogen est the Ueine. As is well known the urine contains nitrogen in very different forms, such as urea, uric acid, kreatinin, ammoniacal salts, etc. It may be of importance in answering physiological questions to determine quantitatively the entire amount of nitrogen elimi- nated with the urine in these different forms ; therefore I give here the method given by Voit and Seegen for this purpose. Since in estimating urea in the urine by Liebig's method, not only the urea is precipitated, but other nitrogenous constitu- * Journ. flir pract. Chemie, Band 44, p. 253 Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 313 ents of the urine also, sucli as kreatinin, etc., form compounds with the mercuric nitrate, we can, according to the investiga- tions of Voit,* Parkes, and Wollowicz,t calculate from the urea found by Liebig's method, the total quantity of nitrogen with tolerable accuracy. Voit found in an average of seventeen combustion analyses in 700 cc. of human urine 9 "SI grm. of nitrogen, while 94 grm. were reckoned from the urea found. Parkes and WoUowicz found in twenty-six combustion analyses that the amount of nitrogen eliminated in twenty-four hours averaged 16-46 grm., while from the urea found by Liebig's method after precipitating the chlorine, 16*34 grm. of nitrogen were obtained on the average.- S. Schenk:]; obtained results which differed somewhat ; he determined the nitrogen in hu- man urine by combustion with soda-lime and by Dumas's method, and in addition calculated from the urea obtained. "While the two methods of estimating the nitrogen gave nearly the same results, the calculations from the urea showed devia- tions. In an average of eight estimations, combustion gave 0*1395 grm. of nitrogen for 10 cc. of urine, while 0"1385 grm. was reckoned from the urea. The greatest deviations which Liebig's method gave in comparison with the direct determina- tion of nitrogen amounted to — 0'014 and +0'021 for 10 cc. of urine ; if the twenty-four hours' quantity of urine had amounted to 1,000 cc, there would have been found 1-4 grm. of nitrogen too little or 24 grm. too much. Schenk on the strength of his experiments declares Liebig's method unserviceable, as well for estimations of urea as of nitrogen, and, consequently, for all ex- periments upon the metamorphosis of tissue ; and since the estimation of urea by the method of Heintz always gave less nitrogen than by other methods, he regards it as the most suit- able for ascertaining the true quantity of urea in the urine. Moreover, it has been shown that the deviations of the direct estimations of nitrogen and the quantities calculated from the urea by Liebig's method nearly balance in long series of experi- ments, and such only come in question in experiments upon the metamorphosis of tissue, by the averages reported by Voit, * Zeitschrift f. Biologie, Band 3, p. 469. t Chem. Centralblatt, 1870, p. 631. X Centralblatt f. d. med. Wissensolialten, 1869, p. 853. Wiener Sitzungsbe- richt. 59, p. 163. Digitized by Microsoft® 314 ANALYSIS OF TEE URINE. Parkes, and Wollowicz, as well as by those obtained by Schenk also. In conclusion, with regard to the estimation of urea by the method of Heintz and Eagsky, concerning which Schenk asserts that there is no suspicion. that the results could prove too small, and that we know of no other body in the urine than urea which on heating with sulphuric acid yields am- monia, Heintz* himself has shown that his method yielded for 1,000 parts of urine about 0'3 urea too much, since kreatin, oxaluric acid, and the extractive matters also gave a little am- monia on heating with sulphuric acid. Liebig's method will not deviate much more from the truth, and, therefore, will probably only be abandoned when a method is found which with the same ease will yield really absolute figures for the urea. A. Principle. All organic nitrogenous bodies which do not contain the nitrogen in the form of nitric acid, etc., are so de- composed by ignition with soda-lime that all of the nitrogen escapes in the form of ammonia, which can be easily collected in sulphuric acid of known strength, and be determined by titration. One equivalent of NH3=17, corresponding to one equivalent of ^=14. B. Preparation of the Solutions. It is well to use for this pur- pose a dilute sulphuric acid, which contains in 1,000 cc. exactly 40 grm. of anhydrous sulphuric acid, and is therefore normal. 60 grm. of concentrated English sulphuric acid are, therefore, weighed off, diluted with 1,020 cc. of water, and the amount of sulphuric acid in each 20 cc. of this dilute acid is then deter- mined by precipitation with chloride of barium. If, for instance, we have found that 20 cc. contain 0"840 grm. of sulphuric acid, then 1,000 cc. contain 42 grm. Therefore 1,000 cc. of this acid (40 : 1,000=42 : x) must be brought to 1,050 cc. by adding 50 cc. of water, in order to obtain an acid which is normal, that is, con- tains exactly 1 equivalent of 80^=40 grm. in the liter. Each cc. of this acid corresponds to ^^'^^ equivalent of nitrogen=0-014 grm. Standard Sodic Hydrate Solution. This must be equivalent to the sulphuric acid, that is, equal volumes of the two must ex- actly saturate each other. 20 cc. of the dilute acid, colored * Heintz, Lehrbuch. der Zoochemie, p. 179. Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 315 feebly red with tincture of litmus, must be exactly neutralized by 20 cc. of the sodic hydrate solution, free from carbonic acid, so that after the addition of the last drop of the 20 cc. of the sodic hydrate solution, the red color of the sulphuric acid changes to a clear blue. (To prepare such a sodic hydrate so- lution, see § 76, B, 2.) C. Ths Distilling Apparatus. This consists of a strong flask of about 100 cc. capacity, whose neck, which is 10 or 12 ctm. long, is closed by a doubly perforated rubber stopper. One hole in the stopper receives a bent glass tube, e, which is connected with a Varrentrapp-Will nitrogen apparatus, /. A straight glass tube with an opening two mm. in diameter is passed through the other hole and serves to aspirate air through the apparatus after the completion of the combustion, so that the products of combustion may be carried over into the receiver; it therefore extends into the body of the flask nearly to the soda- lime. The outer end of this tube is drawn out to a point and hermetically sealed. After the end of the combustion the point • is broken off. The flask is placed in a sand bath of copper plate, and to prevent the deposition of water on that portion of the neck of the flask uncovered by sand, the latter is surrounded by a metallic cover, c, which reaches to the stopper. The sand bath is heated by a Bunsen lamp. A good flask suffices for many estimations. The whole arrangement of the apparatus is shown in fig. 38, on the following page. D. Process. 20 cc. of the standard sulphuric acid are intro- duced into the nitrogen apparatus 'first, soda-lime freshly ignited is put into the flask, so that the bottom is covered about 1'5 ctm. deep, and then the whole apparatus is put together. When this is accomplished 5 cc. of urine are allowed to flow on to the soda-lime, and the stopper is quickly introduced. The soda- lime must be sufficient in quantity to absorb all of the urine, and it must be uniformly saturated by the urine, so that no layer of fluid remains standing above it. The sand bath is flUed with sand up to its edge, so that the metallic cover stands in the sand, and then it is heated as long as any evolution of gas is observable. Heating for half an hour to a red heat is suf- ficient to expel into the receiver all of the nitrogen in the form of ammonia from 5 cc. of urine. When the liberation of gas has at last wholly ceased, the fine point of the tube d is broken Digitized by Microsoft® 316 ANALT8I8 OF THE UBINK off and air is drawn through the apparatus by means of a rub- ber tube drawn over the end of the receiver, so that the last traces of ammonia are brought into the sulphuric acid. The combustion is now finished, the nitrogen apparatus is removed, the sulphuric acid is poured into a beaker, thoroughly rinsed out with water, and the non-saturated sulphuric acid titrated back with the equivalent sodic hydrate solution. Each cc. of the sulphuric acid saturated by the ammonia set free indicates 0"014 grm. of nitrogen. Example : One cc. =0*014 grm. of nitrogen. The quantity of urine passed in twenty-four hours =1300 cc. 5 cc. of urine were used in the analysis. Of the 20 cc. of sulphuric acid contained in the nitrogen apparatus 7*5 cc, as determined by titrating back with the sodic hydrate solution, were saturated, which, therefore, corresponded to 7-5 X 0-014 grm. =0-1050 grm. nitrogen. The total quantity of nitrogen eliminated with the urine in twenty- four hours : 5 : 0-1050 = 1300 : a; = 25 -2 grm. Digitized by Microsoft® qUANTITATIVM ESTIMATIONS. 317 If a large air pump is available, the following procedure may be adopted, according to Voit : * Fine ignited quartz sand is placed in a very shallow porcelain capsule of about 8 cm. dia- meter, a glass cover is then fitted on its broad edge, and the whole apparatus is weighed. 5 cc. of urine are then allowed to flow from a small accurate pipette on to the quartz powder, which must be present in sufficient quantity to completely absorb the fluid, and the apparatus is weighed once more to confirm the measurement. The uncovered dish is now placed under the bell of the air pump together with sulphuric acid, and in a few hours the caked mass becomes so dry that it can be re- moved in fine powder by scraping from the walls of the dish with the back of a broad knife. The powder thus obtained is mixed with soda-lime and ignited as usual in a combustion tube. The liberated ammonia is collected in standard sulphuric acid, which is best kept in a U-shaped tube, and the quantity deter- mined as given above by titrating back the non-saturated acid. The estimation of nitrogen is best combined with that of the total solids of the urine according to my method (§ 59, 2). The process is completed as usual, except that in collecting the ammonia a U-shaped tube is used instead of a small flask, and quartz sand instead of bits of glass. The ammonia set free by evaporating the urine and drying the residue is titrated in the usual way, calculated as urea, and the urinary residues found by weighing are added to it. If all of the solid constituents of the urine have thus been determined, the combustion in the tube with soda-lime is performed with the dry residue, but the amount of ammonia already determined, which was formed by the evaporation, etc., from the decomposition of the urea, is added to that last obtained. The small quantity of nitrites or nitrates which every urine contains does not derange the result, since according to investi- gations of E. Schulze t small quantities of nitric acid, in the presence of large quantities of organic matter, are likewise com- pletely changed into ammonia on being ignited with soda-lime. * Zeitsclirif 1 1 analyt. Chem., Band 7, p. 398. t Zeitschrift f. analyt. Chem., Band 6, p. 379. Digitized by Microsoft® 318 ANALY8ia OF THE UBINE. § 82. Estimation of the Fat. Probably in the very rarest cases would it be of interest to determine quantitatively the fat which occurs in the urine, at most only in very small quantity. If such an estimation, however, is to be undertaken, 20 or 30 cc. of urine are evapo- rated to dryness on the water bath, and the residue obtained is dried in the air bath for a long time at 110". In order to extract the fat, ether is poured over the residue, thoroughly but carefully mixed with it, and allowed to digest for some time with frequent stirring. The clear ether is then poured off into a light glass tube which has been weighed, fresh ether is added to the residue, and this operation is repeated until the ether takes up nothing more. The ethereal extracts are evaporated in the weighed glass cylinder and the residue which remains is calculated as fat. It must be observed, however, that in this calculation, when the urine contains free lactic acid, the weight of the ethereal residue will be thereby increased, since free lactic acid is also soluble in ether. It is well, therefore, to wash the residue repeatedly with water until it ceases to take up anything, and then to dry and weigh. § 83. Estimation of the Biliary Acids. Although even when icterus is very intense, only very small quantities of the biliary acids ever pass into the tirine, still, ac- cording to Hoppe-Seyler,* they may be approximately estimated with the polarizing apparatus. The biliary acids are separated from at least 400 or 600 cc. of icteric urine according to the method given by Hoppe-Seyler and described in § 29. The alcoholic solution of the biliary salts, decolorized with animal charcoal if necessary, is next concentrated to a small volume, measured, and. then examined with the polarizer according to § 70, 3. Since now the specific rotation of cholate of sodium in alcoholic solution amounts to +314°, while that of sugar for medium white light amounts to + 56, the degrees read off on the scale and nonius must be recalculated. The per cent, of cholic acid in the alcoholic solution is found according to the formula * Dessen Handtouch, 3^ Aufl., p. 386. Digitized by Microsoft® QUANTITATIVE ESTIMATIONS. 319 It-I ~P' ^^d the weight of the cholic acid in the amount of urine subjected to examination is found by the formula j^tt • 3^^= x. In this formula a is the rotation found with an observing tube O'l m. long, V the volume of the alcoholic solution of the cholate of sodium in cubic centimeters, and x the weight of the cholic acid contained therein. Moreover, if v, the volume of the alco- holic solution of cholate of sodium, corresponds to 500 cc. of icteric urine, f gives the percentage of the biliary salts in the urine. It is not always the case, as is here assumed, that only cholic acid is contained in the urine, but since the difference in the rotation of glycocholic and cholic acids is only very slight, the error caused thereby falls within the limits of errors of ob- servation, and may, therefore, be disregarded. (Hoppe-Seyler.) § 84 Estimation of the Indican by Jaffe's Method.* Principle. If a colorless or feebly-yellow solution of indican is treated with about an equal volume of pure hydrochloric acid, then a few drops of a saturated solution of calcic hypochlo- rite are carefully added, and the mixture shaken, it instantly becomes of an intense blue color, and is rendered cloudy by the separated indigo, which in a few minutes becomes flocculent, and settles completely in a few hours. Human urine is very rarely blue or green, but usually assumes a red or violet shade after the addition of calcic hypochlorite ; nevertheless such a specimen after filtration leaves a distinct blue tinge on the filter. Process. 1,000 or 1,500 cc. of urine are rendered alkaline by milk of lime and the phosphates are completely precipitated by chloride of calcium. After standing twelve hours the mix- ture is filtered and the filtrate and wash water evaporated to a thick syrup, first over a free flame and then on the water bath. At the same time the reaction must be tested from time to time and finally a little carbonate of sodium added. The syrupy residue is warmed several minutes with about 500 cc. of strong alcohol, it is introduced into a beaker, left at rest for twelve or twenty-four hours for the complete separation of everything * ArcMv f. d. g. Physiologie, Band 3, p. 448. Zeitschr. f. analyt. Chem., Band 10, p. 136. Digitized by Microsoft® 320 ANALYSIS OF THE UBINB. precipitable, it is then filtered and the alcohol distilled off. The residue is dissolved in a large quantity of water and pre- cipitated with a very dilute solution of ferric chloride, at the same time avoiding a great excess. The filtrate from the iron precipitate is treated with ammonia, heated to boiling, and after removing the ferric hydrate which has separated, it is evaporated to a volume of from 200 to 250 cc. With this fluid, which, as a rule, must be filtered once more, the estimation' of the indigo is carried out as follows : First, the amount of cal- cic hypochlorite solution necessary to separate the indigo must be ascertained. For this purpose 20 or 40 cc. of the fluid are measured off and gradually diluted with measured quantities of water, until 10 cc. of the mixture treated with an equal vol- ume of hydrochloric acid assume a just perceptible blue color when one drop of a saturated solution of calcic hypochlorite is added ; the boundary of the reaction has then been reached. It has been found by many experiments that the number of volumes of dilution, which can be added to a solution of indi- can before the above limitoccurs, amounts to about double the number of drops of the calcic hypochlorite solution which are necessary to produce the maximum separation of indigo in 10 cc. of the indican solution. If, then, the above experiment gave the last visible blue color after diluting with water eight times, for every 10 cc. of the undiluted urinary fluid, about four drops of the calcic hypochlorite solution are necessary for the com- plete decomposition of the indican, after diluting ten times five drops, etc., etc. We can, therefore, readily determine the necessary quantity of chlorine if we ascertain with a part of the urinary fluid at what dilution the indican reaction just disappears, and in order to be sure, for every 10 cc. we take one or two drops of calcic hypochlorite solution more than half the volumes of dilution. If we have thus found that the limit of the reaction has been reached at a dilution of eight times, we measure off 200 cc. of the urinary fluid, which correspond to a definite volume of the original urine, add an equal volume of hydrochloric acid and then the calculated number of drops of calcic hypochlorite solution drop by drop with constant stirring, in our case, there- fore, about 100 drops. We let it stand at least twelve hours to allow the indigo which has separated to deposit completely. Digitized by Microsoft® QUANTITATIVE BBTIMATI0N8. 321 We then filter through a very thick Swedish filter, previously- extracted with hydrochloric acid, dried at 150° 0. and weighed, and wash successively with cold water, then with hot water, with dilute ammonia, and lastly once more with water, dry at 105° or 110° C; and weigh. Jaffe found 4-5 to 19-5 mgrm. of indigo in 1,500 cc. of normal urine. Horse's urine contains on the average about twenty-five times as much indigo as human urine. J. Eosenstern * found a considerable increase of indican in the urine in Addison's disease. The amount of indican in this case amounted to from 53 to 80 mgrm. in 1,000 cc. of urine ; it averaged 64-5 mgrm. § 85. Estimation of the Oxalic Acid. For estimating quantitatively the oxalic acid which is pre- sent not as a sediment, we may follow the same method which I have given above, § 45, C, for detecting oxalic acid in urine which has not deposited a sediment. After standing twenty- four hours, the separated calcic oxalate is transferred to a small filter, the weight of whose ash is known, it is washed, dried, and the calcic oxalate transformed by a strong red heat into caustic lime. The amount of caustic lime obtained multi- plied by 1*6071 gives the corresponding amount of oxalic acid =e,HA [CAO,]. The method given by O. Schultzen t for the same purpose gives less reliable results, since, as Salkowski | states, Senator has proved that calcic sulphate is precipitated at the same time by this procedure. * Virchow's Archiv, Band 56, p. 27. , f Reicliert u. Dubois-Reymond's Arcliiv, 1869, p. 718. J: Archiv fiir patholog. Anatom., etc.. Band 50. 31 Digitized by Microsoft® DIVISION THIED. SYSTEMATIC COURSE OF QUALITATIVE AND QUANTITATIVE ANALYSIS OP URINE. I. QxJALITATrVE ANALYSIS. §86. The qualitative analysis of a urine may naturally be per- formed in two different ways, according as we wish to ascertain the presence or absence of any normal or abnormal constituent of the urine, or to obtain a complete qualitative representa- tion of the urine passed at any given time. In the first case a few tests are sufficient, as a rule, to obtain our object ; but in the second it is well to follow a plan which includes all of the indi- vidual substances. The following section may be regarded as such a plan, in which consideration is taken of all of the nor- mal constituents of the urine, as well as of the most important and most common abnormal constituents ; while w^ith regard to those which are more rarely met with, and those which require very large quantities of urine for their investigation, I must re- fer to the sections in Division First, in which they are treated. Moreover, since I have already described at length in Division First the processes for detecting all of the constituents of the urine, it will suffice here to give merely a schedule of the pro- cesses to be carried out, and with regard to their special per- formance to refer to the former sections. A. Systematic Peocess fob Detecting the Soluble OONSTITUENTS. §87. 1. The reaction is tested with litmus paper. a. If the urine is acid and contains no sediment, we proceed as described in 2. 322 Digitized by Microsoft® QUALITATIVE ANALYSIS. 323 b. If the urine is acid and contains a sediment, we allow it to settle, pour off the clear urine, filter if necessary, and test it according to 2. The sediment is to be examined microscopically according to §88. c. The urine is neutral or alkaline. In this case there is usually a sediment in it ; the sediment is tested according to § 88, and the filtered urine according to 2. 2. A small portion of the urine rendered acid, if it is not already so, by a drop of acetic acid, is heated to boiling. If a coagulum is formed which does not disappear after the addi- tion of nitric acid, it consists of albumen. We then separate all of the albumen from a larger quantity of urine (500 or 600 cc.) by boiling (§ 23, E), filter, and treat the filtrate according to 3. The reaction with nitric acid serves as a confirmatory test (§ 23, C, 9), also the test with carbolic acid by the method of Mehu, page 97. If the quantity of albumen is very small, the nitric acid is very carefully covered with a layer of the urine to be tested ; mere traces of albumen produce a turbidity in the form of a sharply defined zone at the point of junction of the two fluids (§ 23, E), at the end. The resulting coagulum is either : a. White, when it consists of pure albumen ; b. Greenish, when we have reason to suspect biliary matters, especially if the urine itself was deeply tinged (§ 28) ; c. Brownish red, when we may suspect the presence of blood ; we therefore test the sediment carefully, according to § 88, and test the original urine with the spectroscope according to § 51, B, 1 and 2. The dried coagulum is treated with alcohol and a few drops of sulphuric acid. If the fluid after filtration is more or less red, it is first tested for hsematin with the spec- troscope (§ 51, B, 2), then evaporated to dryness and ignited. The residue is heated with water to which a little hydrochloric acid has been added, it is filtered and the solution tested with sulphocyanide of potassium. The occurrence of a red color indicates the presence of iron. Hsematin in solution is tested by Heller's test (§ 51, B, 2, c). A specimen of the urine is heated to boiling, concentrated po- Digitized by Microsoft® 324 ANALYSIS OF THE UBINE. tassio hydrate is added and the color of the fluid observed, as well as the color of the earthy phosphates which are separated in flocculi after standing for a short time. Another specimen is treated with ammonia, then with tannin solution, and lastly with acetic acid until the reaction is dis- tinctly acid. The precipitate which may occur is treated exactly according to § 51, B, 2, d, and finally used for the pro- duction of hsemin crystals which are so characteristic of blood pigment. 3. About 600 or 800 cc. of clear urine or of urine separated from its sediment or albumen coagulum by filtration are evapo- rated on the water bath to the consistence of a thick syrup, and the residue obtained is divided into two portions (| and i). a. One-third of this residue is extracted with strong alcohol, the undissolved portion is allowed to settle, the solution is filtered, the residue again washed once or twice with strong alcohol, and the solution tested as follows (aa), and the residue according to c. aa. A small quantity of the alcoholic solution is evaporated nearly to dryness on the water bath, and the residue tested for urea by adding nitric or oxalic acids (§ 2, D, 9, a and b). bb. The greater part of the alcoholic solution is treated with a few drops of milk of lime, and then with a solution of chloride of calcium as long as any precipitate is produced by it. The filtrate is evaporated on the water bath to 10 or 12 cc, introduced into a beaker, and after cooling treated with J cc. of an alcoholic solution of chloride of zinc. After being well shaken the mixture soon becomes cloudy and Icreatinin- chloride of zinc is formed. The precipitate collected after a few hours is tested microscopically according to § 3, C, 1. Large quantities of kreatinin may be easily obtained as de- scribed in § 3, D, and § 5, D, 2. b. Two-thirds of the residue are slightly acidulated with hy- drochloric acid, rubbed up with powdered sulphate of barium, and then extracted with alcohol. The alcoholic solution is used for testing for Mppwric acid, as described in § 8, E. The crystals obtained are examined microscopically (Plate I, fig. 1), and, as far as the material serves, chemically also (§ 8, D, 7). Digitized by Microsoft® qUALITATIVE ANALYSIS. 325 The detection of Mppuric acid according to § 8, E, 2, is very easy and certain. The kreatinin can be precipitated by chlo- ride of zinc solution from the urinary extract after exhaustion with ether, after it has been exactly neutralized with sodic hy- drate solution and diluted with 30 cc. of absolute alcohol. The saline mass precipitated from the evaporated urine by absolute alcohol is tested for any succinic acid which may be present, as described in § 8, E, 2. c. The residue which has been obtained by treating with al- cohol, according to a, is covered with dilute hydrochloric acid (one part of hydrochloric acid and six parts of water) in the evaporating dish, and the undissolved portion separated by a small filter. aa. The hydrochloric acid solution contains the earthy phos- phates and other salts ; the former are precipitated by neutral- izing the solution with ammonia. bb. The residue which is left contains mucus and uric acid. After washing it, the filter is perforated and the regidue washed, by means of a wash bottle, into a small test tube, two or three drops of sodic hydrate solution are added, it is heated and filtered. a. The undissolved residue is mucus. /?. The filtrate contains the uric acid, which when treated with hydrochloric acid separates in crystals which are ex- amined under the microscope (§ 6, c). The remainder is dis- solved in nitric acid, carefully evaporated to dryness and exposed to ammonia, as mentioned in § 6, E, 1, a. If a purple violet color is formed, which becomes purple blue on adding potassic hydrate, it is absolute proof of the presence of uric acid. If the residue is immediately treated with sodic hydrate or potassic hydrate instead of with ammonia, a purple violet solu- tion results, which becomes paler on heating, and at last wholly loses its beautiful color. (Distinction from xanthin.) The uric acid is easily obtained in finely formed crystals, if 200 cc. of urine are treated with 5 cc. of hydrochloric acid, and left at rest for twelve hours (§ 6, E, 2). d. The alcoholic extract of a large quantity of urine is re- quired in testing for lactic acid (§ 30, C). e. The method described in § 5, D, for the simultaneous de- Digitized by Microsoft® 326 ANALT8I8 OF THE URINE. tection of kreatinin, xanthin, and urea, gives witli certainty the desired result. f. Oxaluric acid can only be detected by using very large quantities of urine (§ 7, E). 4. Three or four cc. of fuming hydrochloric acid are mixed in a test tube with twenty or twenty-four drops of the urine to be tested. If uroxanthin (indican) is present, the mixture in a very short time becomes colored a red "violet or intense blue. If on account of the minute quantity of uroxanthin present, the reaction does not take place, it may often be produced by adding a few drops of strong nitric acid (§ 10, IV. c). The test with calcic hypochlorite by Jaffa's method (§ 40, IV. c, 2) is also very delicate. In testing for urobilin we proceed exactly according to § 10, 1, c. 5. If the urine is colored more or less deeply brown or green, etc., if it foams on being shaken, and if a piece of filter paper is colored yellow or green on being dipped into it, we havej reason to test for hile. a. A small quantity of urine is poured into a conical-shaped glass, and nitric acid containing nitrous acid is added, drop by drop, without shaking. If in the lower part of the fluid a color is formed which passes through green, blue, violet to red, and lastly into yellow, the presence of the bile pigments is indi- cated. If there are only slight traces of bile pigment present, the nitric acid is to be carefully covered with a layer of the urine to be tested, or the bile pigment is to be first separated with chloroform (§ 28, D, 1 and 2). b. In testing for the biliary acids, 400 or 600 cc. are evapo- rated on the water bath' and the alcoholic extract employed. For the process see § 29, under Detection. Pettenkofer's test, as stated there, is performed in a porcelain dish. If the reaction mentioned does not occur, but the urine be- trays the presence of biliary pigment by its color, this may be choletelin, the last yellow product which results from the ac- tion of nitric acid, etc., on bilirubin. In this case we test according to § 28, D, 3, and confirm by the spectroscopic test. To detect the biliary acids in normal urine they are to be separated with chloroform according to Dragendorff's method {§ 29, Detection, 3). Digitized by Microsoft® QUALITATIVE ANALTSIB. 327 6. If there is any reason to test for sugar : a. Fifteen or twenty drops of the urine in question are diluted with 4 or 5 cc. of water, | cc. of sodic hydrate is added, and then a very dilute solution of sulphate of copper is dropped in. If sugar is present, red suboxide of copper separates imme- diately on heating, but in the cold only after standing a long time (§ 25, D, 7). If the reduction is not weU marked, if the suboxide of copper remains in solution, the urine is filtered through animal char- coal until it is completely decolorized, and is then used for the aboTe test. The following serve as confirmatory tests : a. The potash test. § 25, D, 5. yS. The bismuth test. § 25, D, 10. y. The indigo reduction test. § 26, D, 6. 6. The silver reduction. § 25, D, 9. e. The fermentation test. § 25, D, 8. b. If the reactions given under a are not decisive, if, indeed, only traces of sugar are present, it must first be separated in a pure form, according to § 25, E, II., and the solution obtained be finally used for the above reactions. 7. If the urine has the odor of sulphuretted hydrogen, if it colors brown or black a piece of paper moistened with basic acetate of lead (§ 34), the presence of sulphuretted hydrogen is indicated. 8. To test the urine for inorganic substances, a portion (80 or 100 cc.) should be evaporated to dryness and the residue ig- nited, as described in § 60. The ash is extracted with water, filtered, and tested as follows : a. A small portion of it is rendered acid with hydrochloric acid, and chloride of barium is added ; a white pulverulent precipitate indicates the presence of sulphuric acid. b. A second portion is made acid with nitric acid, and a so- lution of nitrate of silver is added. A white curdy precipitate indicates chlorine. c. A third portion is treated with acetate of sodium, acetic acid, and a few drops of uranium solution ; a yellowish- white gelatinous precipitate indicates phosphoric acid. d. The rest of the aqueous solution is evaporated to dryness, and a small portion of the saline mass heated to redness on a Digitized by Microsoft® 328 ANALYam OF THE UBINE. platinum wire in the inner flame of the blowpipe ; a yellowish color of the outer part of the flame indicates sodium. e. The rest of the saline mass, obtained as indicated in d is dissolved in a few drops of water, and platinic chloride added. A yellow crystalline precipitate indicates potassium. To test for lithium, which readily passes into the urine on being taken internally, the dried saline mass obtained in d is next repeatedly treated with absolute alcohol, the alcoholic solution is evaporated to dryness, and the residue tested with the spectroscope. Salts of lithium give a beautiful bright red line between the Frauenhofer lines B and 0. 9. The residue of 8, treated with water, is heated with hydro- chloric acid, filtered, washed, and tested as follows : a. A small portion of the solution is boiled with a drop of nitric acid, and sulphocyanide of potassium is added ; if a red color is produced iron is present. b. The rest is treated with an excess of acetate of sodium and tested for calcium with oxalate of ammonium. c. All of the calcium is precipitated, the fluid separated by filtration, and ammonia added to the filtrate. A white crystal- line precipitate of ammonio-magnesian phosphate indicates the presence of magnesium. Most of these tests (8 and 9) can be performed with the origi- nal urine, filtered if necessary, yet they give clearer and more distinct results when the tests are applied to the ash. 10. In testing fo'r ammoniacal salts, 50 or 100 cc. of urine are treated with milk of lime in a flask, in the body of which a piece of moistened turmeric paper is suspended from the stopper. If ammonium salts are present the paper quickly becomes brown (§ 19). 11. The possible presence of iodine is best detected by dis- tillation with sulphuric acid according to § 71, C. The distillate obtained, after removing the sulphurous acid, may be tested for iodine with a few drops of starch paste, and the careful addition of chlorine water, or, better still, of red fuming nitric acid instead of with the palladium solution (§ 71, C). The smallest traces of iodine will give rise to the formation of blue iodide of starch. For other methods of testing for bromine and iodine see § 56, I. C, 8, 9, and § 71, 2. 12. In testing for the volatile fatty acids and carbolic acid Digitized by Microsoft® BEGOGNITION OF SEDIMENTS UNDER MIGBOSOOPE. 329 large quantities of urine are necessary, and the analysis should not be undertaken with less than 50 or 60 pounds of urine. For the methods see § 9 and § 31. 13. Benzoic acid is only found in decomposed alkaline urine. 6 or 8 pounds are requisite to detect it satisfactorily. Benzoic acid is best found in fermented diabetic urine. To separate it we must proceed exactly as is described in § 32, D. 14. Inosite has hitherto only been found in cases of Bright's disease and diabetes (§ 27, D). 15. AUantoin. See § 85, E. 16. To test for xanthin we require large quantities of urine (§5,D). 17. Leucin and tyrosin have been found in acute atrophy of the liver, typhoid fever, small-pox, etc. It is probable that the urine then contains, in addition to these substances, valerianic acid also. For the methods of d'etecting see § 37, E. 18. For nitric acid, nitrous acid, and peroxide of hydrogen, we test according to § 21 and § 22. 19. We test for oxymandel acid as in § 38 ; it has thus far only been found in acute atrophy of the liver. ^0. We test for brenzcatechin according to § 39. 21. For acetone we test according to § 41. n. Eeoognition op Sediments undee the Miceoscope. §88. If we wish to examine the sediment of a urine, it is neces- sary to know first whether the urine in question is fresh, or whether it has already stood a long time, and the changes which are caused by fermentation have commenced. We there- fore test its reaction, let the sediment subside completely in a closed vessel, pour off the supernatant fluid, which must be examined according to § 87, and place a drop of the sediment on a glass slide. If the quantity of urine is small, it is poured into a champagne glass and left at rest until the fluid has be- come clear. The supernatant fluid is then removed with a si- phon, and a drop of the sediment which has collected in the apex of the glass is placed on a glass slide. If the quantity of urine is large, that of twenty-four hours, it is first allowed to Digitized by Microsoft® 330 ANALYSIS OF TEE UBINE. settle in a covered vessel, tlie clear fluid is then drawn off with a siphon, the rest is put into a champagne glass and again al- lowed to settle, and we then proceed as before. The drop on the slide is next covered with a covering glass and systemati- cally examined, by beginning on one side of the specimen and pushing it back and forth under the objective until every point of it has been in the field of vision. When we have examined one specimen, a second is taken, etc.; it is advisable, also, to take specimens from different layers of the sediment, since some bodies sink more rapidly than others. When it is pos- sible, the microscopic examination should be made twice ; first, as soon as possible after the urine has been passed, and again when the urine has stood twenty-four hours. Calcic oxalate, for example, is not usually found in freshly passed urine, but first makes its appearance after the lapse of a few hours. We increase our magnifying power from 50 or 80 diameters up to 300 and 400. If the urine has been filtered to separate the sediment and the latter is removed from the filter by scraping, we must be careful to avoid regarding paper fibres, etc., as con- stituents of the sediment. A. TIk, Urirw has an Acid Beaction. " 1. Tfi£ whoh sediment is amorphous, arranged partly in irregu- lar heaps, or in branched mossy rows of very small granules. A drop is heated on a glass slide. a. If complete solution takes place it indicates the presence of urates. (Plate II., fig; 1 and 2.) After it has cooled, a drop of hydrochloric acid is added, and it is allowed to stand for a quarter or half an hour ; the formation of rhombic tables of uric acid proves the presence of this substance. (Plate I., fig. 2.) In most cases this sediment consists of a mixture of acid urates, and is distinguishnd by a more or less red color. (Plate II., fig. 1 and 2.) The sediment is tested chemically, according to §44. These sediments are very frequently accompanied by uric acid and calcic oxalate crystals. (Plate I., fig. 3 ; and Plate 11., fig. 4.) b. If the sediment does not dissolve on being heated, but does dissolve in acetic acid without effervescence, calcic phos- phate is probably present. We confirm chemically as in § 46. c. If we find in the amorphous sediment small, highly re- Digitized by Microsoft® BECOONITION OF 8EDIMENT8 UNDEB MICItOSOOPE. 331 fractive, silvery, shining drops, which are soluble in ether, they indicate the presence oifat (§ 33). 2. The Sediment cmitains weH-formed Crystals. a. Small, shining, perfectly transparent, highly refractive, en- velope-shaped, rhombic octahedra, insoluble in acetic acid, are calcic oxalate crystals. (Plate I., fig. 3 ; Plate II., fig. 4, § 45.) (300 or 400 diameters.) b. Four-sided tables, or six-sided plates of rhombic shape, from which spindle- or barrel-shaped crystals are formed by the rounding of their obtuse angles, are uric add. These sedi- ments are usually more or less colored. (Plate I., fig. 2 and 3; Plate II., fig. 4; Plate ni., fig. 1, § 6, C.) "We can detect it chemically by the murexid test (§ 6, E, l.a). _ _ ,_ If there is doubt about some of the forms, the sediment is dissolved in a drop of sodic hydrate solution on a glass slide, a drop of hydrochloric acid is added, and the forms which now appear .are observed. Just at the commencement of the alkaline fermentation the uric acid crystals, which are more or less dissolved, are fre- quently studded with groups of prismatic crystals consisting of urate of sodium, upon which again are deposited concentrically striped spheres of urate of ammonizim. Not unfrequently soli- tary crystals of calcic oxalate are found at this time also. c. Regular six-sided tables, which dissolve in hydrochloric acid and ammonia, char and burn on heating, and which give a precipitate of sulphide of lead when boiled with a solution of lead oxide in caustic soda, consist of cystin. (§ 47, Plate III., fig. 4.) The test with nitroprussiate of sodium for cystin is very deli- cate (§ 47, 0, 8). d. Prismatic, often wedged-shaped crystals which sometimes lie singly, and sometimes with their pointed ends so placed to- gether that they form a more or less complete circle, consist of crystallized calcic phosphate (§ 46, 2). These crystals are quite soluble in acetic acid. e. Heavy, greenish-brown, spherical granules with a stellate crystalline structure may consist of tyrosin. Saturating its am- moniacal solution with acetic acid precipitates characteristic groups of long shining needles (§ 37, B). , Digitized by Microsoft® 332 ANALYSIS OF THE UBINE. ■ To confirm its presence tte different chemical tests are ap- plied, according to § 37, 0, 2, 3, 4 Urine containing tyrosin very frequently contains bile pig- ments also. f. Hippuric add is very rarely met with as a sediment in the form of needles or rhombic prisms which are readily soluble in hot water (§ 8, B, D). 3. The. Sediment contains Organized Substances. a. Spiral bands which consist of fine points and granules ar- ranged in rows are mucous coagula, and are often accompanied by urates. (Plate II., fig. 2, § 50.) These must not be confounded with so-called casts. (See e.) (§ 53 ; Plate I., fig. 4, 5, 6.) b. Small, strongly contracted and granular bodies, which are usually united by their edges into large groups like a coat of mail, are mucous corpuscles. (§ 50, Plate II., fig. 3.) c. Circular, slightly biconcave disks, which usually appear yellow, become swollen strongly on the addition of acetic acid, and are more less quickly dissolved by it, are blood corpuscles. (Plate III., fig. 1 and 2.) We should pay special regard to the swollen spherical forms, as well as to the distorted, angular, and crenated ones (§ 51). When blood is present the urine contains albumen. d. Kound, pale, faintly granular cells of different sizes, which become swollen considerably by acetic acid, lose their granular surface and present nuclei of different forms and groupings, are pus corpuscles. (§ 52, Plate III., fig. 3.) We cannot distinguish these bodies chemically or microscopically from mucous cor- puscles. (Plate II., fig. 3.) When pus is present, the urine contains albumen. The deposited sediment, when pus is present, is changed to a thick, tenacious, ropy mass by potassic or sodic hydrate so- lution. (Donne's pus test, § 52, B.) e. Cylindrical bodies often studded with blood and pus cor- puscles and accompanied by epithelial cells and mucous corpus- cles are so-called renal casts. (§ 53, Plate I., fig. 4, 5, and 6.) aa. Cylindrical casts whose round nucleated cells are dis- tinctly visible through a fine molecular mass are epithelial casts of the tubes of Bellini. (Plate I., fig. 4.) These forms are usually accompanied by free club-shaped, Digitized by Microsoft® REC09NITI0N OF SEDIMENTS UNDEB MIOBOSGOPE. 333 caudate or spindle-shaped nucleated epithelial cells from the ureters, pelvis, and calices of the kidney. (Plate I., fig. 4.) bb. Solid cylinders of a granular cloudy appearance are the so-called granular renal casts. (Plate I., fig. 6.) These cylinders often contain blood and pus corpuscles as well as fat drops and granules of fat, also crystals of calcic oxa- late and single epithelial cells. The sediment, moreover, frequently contains blood and pus corpuscles as well as the free epithelal cells mentioned under aa. (Plate I., fig. 6.) cc. Solid cylinders of very pale transparent character, so that we can frequently distinguish them from the surrounding fiuid only with great difficulty, are the so-called hyaline renal casts. (Plate I., fig. 5.) Their recognition is rendered easier if a solution of iodine in iodide of potassium or a solution of fuchsin is added to the specimen whereby these bodies assume a yellow or red color. We frequently find intermediate forms between bb and cc, by the hyaline casts assuming a more or less granular appearance, owiug to overlying fat drops, pus corpuscles, and finely granu- lar masses. Every specimen of urine containing albumen must he carefvEy ex- amined for these different bodies. We should choose a power of 180 or 200 diameters. f. Epithelial cells of different forms according to their source. aa. Pavement epithelium. Eoundish, long, or polygonal nu- cleated cells from the large and small labia, the vagina, the female urethra, bladder, pelvis of the kidney, and calices. (Plate I., fig. 4, 5, 6 ; Plate II., fig. 1, § 50, 2.) bb. Cylindrical and oval epithelium from the lower layer of the mucous membrane of the bladder, etc. cc. Ciliated epithelium from the uterus. The addition of a solution of iodine in iodide of potassium or of a solution of fuchsin renders all of these forms more distinctly visible under the microscope. g. Fermentation spores and mycelium accompany sediments of urates, free uric acid, and calcic oxalate in commencing acid fermentation, but occur especially in diabetic urine which has undergone fermentation. aa. The fermentation spores are small nucleated cells which Digitized by Microsoft® 334 ANALTBI8 OF THE UBINE. increase by budding, and thus form simple or branched rows. (Plate II., fig. 1, 2, 4) bb, Mycelium often forms a thick network which may cover the whole field. (See page 189, fig. 5.) h. Short fine rods which move briskly here and there or with a serpentine motion are vibriones; they are commonly seen in feebly acid or alkaline urine with a high power (§ 55). i. Spermatozoa are recognized by their tadpole-like shape (§ 54). k. Masses of Cancer. (Plate III., fig. 5 and 6.) 1. Sarcina ventriculi, Qoodsir. Very rare. Its characteristic form does not admit of its being easily mistaken. (Page 189, fig. 6.) B. The Urine is Alkaline. 1. The Sediment contains Crystals. a. Combinations of the vertical rhombic prism, which resem- ble a coffin lid in shape, are soluble in acetic acid, and on heat- ing with a solution of sodic hydrate evolve ammonia, are crystals of ammonio-mcujnesian phosphate. (§ 46, 1 ; Plate II., fig. 3 and 5.) If calcic oxalate should occur with these, the sediment is treated with a drop of acetic acid on a glass slide ; the crystals of magnesium phosphate will dissolve, while the calcic oxalate will remain behind in its envelope-shaped crystalline form. b. Spherical opaque masses which appear like thorn apples with peculiar, prominent, fine points, but also in glandular con- glomerations consisting of small, curved, club-shaped bodies, are urate of ammonium. (§ 44, 3 ; Plate II., fig. 5.) 2. The Sediment contains Amorphous Masses. In an alkaline urine these almost always consist only of calcic phosphate (§ 46, 2). 3. The Sediment contains Organized Bodies. Besides mucus, blood and pus corpuscles, etc., we find here fermentation spores and mycelium, infusoria, and confervas (§ 55, page 189, fig. 5). In an alkaline urine pus is changed to a ropy slimy mass (§ 52, B). § 89. Pkeseevation of Ukinaey Sediments. As in many cases it may be of interest to preserve urinary sediments as microscopic objects, the following short introduc- Digitized by Microsoft® BECOGNITION OF SEDIMENTS UNDER MICROSCOPE. 335 tion for that purpose may find mention here. Pirst of all it is necessary to separate the sediment from the urinary fluid, as the urine soon undergoes decomposition, and, therefore, organ- ized bodies especially are easily destroyed. The sediment is, therefore, allowed to settle in a champagne glass, the urine as far as possible is drawn off with a siphon, and the sediment is then washed three or four times by decantation with the preser- vative fluid, in which we wish to enclose it later. Two methods are open to us : we may either put the washed sediment into a small bottle, fill it with the preservative fluid, and write the contents on a label, or we may place the sediment on a glass slide and preserve it as a finished preparation under a cover- ing glass hermetically sealed. Of the different preservative fluids proposed for this pur- pose glycerine solution,* creosote and wood spirit solution,t dilute alcohol,:^ Farrant's fluid,§ etc., are best fitted for the va- rious epithelial cells, renal casts, pus and mucous corpuscles, spores, uric acid, urates, calcic oxalate, etc.il Ammonio-magne- sian phosphate is best preserved in water to which a little ammonia has been added. Very dilute acetic acid is selected for cystin. Crystalline sediments, with the exception of am- monio-magnesian phosphate and calcic oxalate, may be pre- served in Canada balsam, but they must first be very completely * Glycerine solution is obtained by diluting commercial, thick, syrupy gly- cerine with equal parts of camphor water. It forms an excellent preserving fluid. f Creosote and wood spirit solution is obtained as follows : Three drams of creosote are mixed in a mortar with six ounces of wood spirit, and powdered chalk is added until the whole forms a thin pulp, which is then diluted with sixty-four ounces of water while being rubbed well together. A few pieces of camphor may also be added. The mixture is then allowed to stand two or three weeks in a closely covered glass, bqing frequently stirred. At last the clear fluid is poured off, filtered, and preserved in a well-stoppered bottle. I Rectified spirit is diluted with from two to eight times its quantity of water. It is less suitable for microscopic preparations, since it is difficult to hermeti- cally seal preparations preserved in alcohol. § A mixture of equal volumes of very thick mucilage, glycerine, and a cold saturated solution of arsenious acid. I] [Reviser's Note. — An excellent preservative fluid for the organized sediments is a solution of the acetate of potassium to which a little carbolic acid has been added. The acetate of potassium solution should have a sp. gr. of between 1-050 and 1-060, and should contain 4 to 5 cc. of deliquesced carbolic acid to the liter of solution.] Digitized by Microsoft® 336 ANALYSIS OF THE URINE. washed and carefully dried. The following procedure is the simplest : The well- washed sediment is placed on a glass slide and allowed to dry thoroughly in the sun or over sulphuric acid ; it is then moistened with a drop of oil of turpentine, the greater part of which is again allowed to evaporate. A drop of Canada balsam is now placed upon it, it is gently warmed, any air bubbles present are removed with a needle, and it is covered with a previously warmed covering glass. By careful pressure the excess of balsam is forced out, and after a few days it dries and forms a perfectly tight border around the cov- ering glass. For still greater security the edge may be covered with asphalt varnish, which is an article of commerce, and may be readily applied with a camel' s-hair brush. To preserve sediments in a fluid we proceed as follows : A drop of the sediment suspended in the preservative is placed on a glass slide and a covering glass previously breathed upon is carefully placed over it with a pair of forceps, taking care that no air bubbles are included under it. The excess of fluid is then removed by gentle pressure, carefully absorbed by filter paper, and the preparation laid aside a few minutes to allow the very last of the fluid to evaporate. We now place the preparation under the microscope to see that everything is right, and then proceed to hermetically seal it. The covering glass is first fastened to the slide by means of wax. The wick of a thin wax taper is sharpened into a chisel shape, then heated to the melting point over a spirit lamp, but not until it burns, and then, while the wick is held horizontally, it is quickly drawn along the edge of the covering glass. In this process drops of wax must not be allowed to fall off, but only just enough to perfectly fill the furrow between the covering glass and glass slide, and the whole border of wax should not be more than 2 mm. wide. "With a little practice the wax may be as evenly laid on as fluid with a brush. When the wax bedding is finished, it is covered with asphalt varnish, which may be easily applied with a hair pencil, so as to cover the wax bed 2 mm. beyond each edge ; we have thus a border about 6 mm. broad, which surrounds the preparation. In applying the as- phalt we must proceed with care, and see that we cover all of the corners and edges well, and that no air bubbles have been included anywhere ; this we can best determine by means of a Digitized by Microsoft® QUANTITATIVE ANALYSIS. 337 hand lens. We should be especially careful not to make this first layer of asphalt too thick, since it then hardens only on the surface, still remaining fluid beneath and easily being drawn under the covering glass and thus spoiling the preparation. I have lost many preparations in this way. If after twenty-four hours the first layer of varnish has become solid, a second thicker one is applied over it, when the preparation may be labelled. The glass slides should be 48 mm. long and 28 mm. broad. Protectors, 10 mm. broad, should be glued on to both ends with mucilage or silicate of potassium varnish, and at the same time they should carry the labels. These protectors are to be recommended very highly, since the covering glass is then never in danger when the preparations are packed one upon another. The finished preparations should never be placed on their edge, since they then more readily become leaky, but they should always be laid flat in a box lined with cloth. The process described here is applicable not only to urinary sedi- ments, but also to many other microscopic preparations.* III. QUANTITATIVE ANALYSIS. §90. If we have obtained a satisfactory knowledge of the urine under examination' qualitatively, according to § 87 and § 88, we proceed to determine the constituents quantitatively. Unfor- tunately, however, we do not yet possess simple and accurate methods for determining q-uantitatively all of the bodies which occur, therefore we must content ourselves with estimating the most important of the normal and abnormal constituents. 1. Estimation of the Quantity of Urine Passed in a Given Time (§57). According to the purpose which we have in view, we either determine the amount of urine for twenty-four hours, or for a shorter time. The amount should be stated in cubic centime- ters (§ 57). * Very thorougli instruction in this subject can be found in Welker's Aufbe- wahrung microseopisclier Objecte, Qiessen, 1856 ; also in Reinhard's Das MicTo- scop und sein Qebrauch fur den Arzt, Leipzig and Heidelberg. Digitized by Microsoft® 338 ANALT818 OF THE URINE. 2. Estimation of the Specific Gravity (§ 58). In most cases tlie determination of the sp. gr. can be made with the Tirinometer, § 58, 1. But if greater accuracy is desir- able, we use the method of weighing, § 58, 2 and 3. The statement of the sp. gr. is rendered more complete by a simultaneous statement of the temperature of the urine. 3. Determiriation of the Water and of the Toted Solids (§ 59). 10 or 15 cc. of urine are evaporated on the water bath in a weighed porcelain crucible exactly according to § 59, and the residue is dried in the air bath at 100° until it no longer loses weight. After subtracting the weight of the crucible we obtain the amount of solid constituents, and if we^ subtract this from the amount of urine taken, it gives us the amount of water in the urine. Much more accurate results are obtained when the evapora- tion of the urine is performed in the apparatus figured in § 59, 2, fig. 17. The ammonia which is liberated by the decompo- sition of the urea when the urine is evaporated is calculated as urea, and this is added to the residue found by weighing. 4. Determination of the Non-volatile Salts (§ 60). 10 ec. of urine are evaporated to dryness in a weighed plati- num crucible, and the residue is ignited as described in § 60. If we, wish to determine the constituents which are soluble in water separately from those which are insoluble, we boil the weighed residue with water, filter, wash, evaporate the aqueous extract to dryness in a weighed platinum crucible, ignite gently, and weigh. The weight of salts soluble in water subtracted from the whole quantity of non-volatile bodies found gives as the difference the amount of salts insoluble in water. 5. Determination of the Coloring Matter hy Vogel's Method. This process is carried out exactly as described in § 61. 6. Determination oftJie Urea. A. The Urine contains no Albumen. 50 cc. of urine are mixed with 25 cc. of a cold saturated solu- tion of caustic baryta and nitrate of barium (§ 65, B, 3), and the resulting precipitate filtered through a dry filter. The filtrate obtained is divided into two portions. a. One portion is made very feebly acid with dilute nitric acid, 15 cc. are measured off with a pipette, corresponding to 10 cc. of urine, and it is treated with a standard solution of Digitized by Microsoft® QUANTITATIVE ANALYSIS. 339 mercuric nitrate from a Molir burette drop by drop until a dis- tinct, permanent, wbitisli cloudiness appears. The number of cc. used up to this point gives the correction for chloride of so- dium and is subtracted from the number of cc. of mercury so- lution used under b (§ 65, D, 3, at the end). (Eautenberg's method.) b. The second portion of the filtrate is not rendered acid, but 15 cc. =10 cc. of urine are also measured off with a pipette, and the urea is determined by the standard solution of mercuric nitrate, § 65, C. This is added from a burette until a drop of the mixture saturated with carbonate of sodium on a watch glass gives a distinct yellow color. If the mixture remains white, there is still some uncombined urea present, and more mercuric solution must be added. The result of the first should be confirmed by a second test ; every cubic centimeter of the mercuric solution used, after subtracting those obtained under a, corresponds to 10 mgrm. of urea. For the principle, preparation of the solutions, etc., see § 65. Corrections. aa. The Urine contains more than two per cent, of Urea.. If more than 30 cc. of the mercuric solution have been em- ployed for the 15 cc. of the urine mixture, before testing the mixture with carbonate of sodium, we must add a quantity of water equal to half that of the mercuric solution in excess of 30 cc. which has been used (§ 65, D, 1). bb. The Urine contains less than two per cent, of Urea. If less than 30 cc. of the mercuric solution have been used for the 15 cc. of the urine mixture, 0"1 cc. must be subtracted for every 5 cc. less than 30 cc. which have been used, and the re- mainder calculated for urea (§ 65, D, 2). cc. The Urine contains one to one and a half per cent, of Chloride of Sodium. If we wish to obtain perfectly accurate results, the chlorine must first be removed by a standard solution of nitrate of sil- ver. The urea in the filtrate is then determined by the mer- curic solution as usual, account being taken of the dilution which has been caused by the nitrate of silver solution (bb). (§ 65, D,3.) The method of Eautenberg described in § 65, D, 3, at the end, gives nearly as accurate results. (See page 239.) Digitized by Microsoft® 340 ANALT8I8 OF THE URINE. dd. Tlxe Urine contains carlonate of ammonium (§ 65, D, 5, b). A measured volume of urine, whicli has been completely precipitated by baryta solution, is subjected to distillation, and the ammonia which is set free is received in a measured volume of standard sulphuric acid (§ 65, D, 5, b). Each cubic centime- ter of the saturated acid corresponds to 11-32 mgrm. of ammo- nia or 20 mgrm. of urea. The undecomposed urea is determined as usual in the resi- due freed from ammonium salts. B. The Urine contains Albumen. The albumen in a definite quantity of urine is coagulated as in § 65, D, 4, filtered, and the urea, after precipitating the phosphates with baryta solution, determined as usual (§ 65, C). For clinical purposes the method of Knop-Hiifner (§ 65), with hypobromite of sodium, is also to be highly recommended. 7. Determination of the Chlorine (§ 66). 5 or 10 cc. of urine are treated with 1 or 2 grm. of pure nitre, evaporated to dryness in a platinum evaporating dish, and care- fully heated until the organic bodies are completely decom- posed. The white saline residue is dissolved in water, accu- rately neutralized with nitric acid, and the chlorine estimated with the solution of nitrate of silver according to § 66, C Each cc. of the silver solution corresponds to 6*065 mgrm. of chlorine or 10 mgrm. of chloride of sodium. 8. Determination of the Phosphoric Acid (§ 67). a. Estimation of the Total Amount. 50 cc. of urine are treated with 5 cc. of an acid solution of acetate of sodium, heated on the water bath, and then the phosphoric acid is determined with a standard solution of acetate of uranium. During the addition it is frequently tested by adding a drop of the mixture to a solution of ferrocyanide of potassium in the manner re- commended in § 67, C, until a slight excess of uranium is in- dicated by a faint red color. Each cubic centimeter of the uranium solution used corresponds to 5 mgrm. of phosphoric acid (§ 67, 0, a). b. Determination of the Phosphoric Add combined with Alkalies. 50 cc. of urine are rendered alkaline with ammonia, the earthy phosphates are filtered off after a few hours, the precipitate is washed, and the phosphoric acid is estimated in the whole filtrate Digitized by Microsoft® QUANTITATIVE ANALYSIS. 341 after adding 5 cc. of the acetate of sodium solution as explained in a. Each cubic centimeter of the uranium solution which was used indicates 5 mgrm. of phosphoric acid which were in com- bination with the alkalies. The quantity thus obtained sub- tracted from the whole quantity previously determined gives as a difference the phosphoric acid combined with the earths. 9. Determination of the Free Acids (§ 68). 50 cc. of urine are treated drop by drop with a solution of sodic hydrate standardized with pure oxalic acid, until the acid reaction has wholly disappeared and a drop placed on litmus paper neither makes it blue nor red. Each cc. of the solution of sodic hydrate used corresponds to 10 mgrm. of oxalic acid. 10. Determination of the Sulphuric Acids (§ 69). 100 cc. of urine are heated to boiling after the addition of 20 or 30 drops of hydrochloric acid, and a standard solution of chloride of barium, each cubic centimeter of which indicates 10 mgrm. of sulphuric acid, is added drop by drop until the neutral point has been reached (§ 69, A), or until a slight excess of barium is indicated by sulphate of potassium in a filtered speci- men. If 12 cc. have been required up to this point, but no re- action with sulphate of potassium has taken place when 11 cc- have been used, the true amount lies between 11 and 12 cc. We immediately add 11 cc. of the chloride of barium solution to a new quantity, heat to boiling, and complete the estimation exactly according to § 69, 0. 11. Determination of the Sugar (§ 70). In this estimation the urine must be diluted so that it con- tains at most I per cent, of sugar. 10 cc. of the standard copper solution are then measured off, diluted with 40 cc. of water, heated to boiling, and the dilute urine added until all of the copper has been reduced, and a filtered specimen, after being rendered acid by hydrochloric acid, no longer gives the copper test with sulphuretted hydrogen. In most cases a proper di- lution is attained by mixing 5 cc. of diabetic urine with 95 cc. of water. However, the dilution must depend on the greater or less quantity of sugar in the urine. The volume of urine employed for the complete reduction contains exactly 50 mgrm. of diabetic sugar. If now we have diluted the urine, for example, to twenty times its volume before Digitized by Microsoft® 342 ANALYSIS OF THE URINE. testing, we must divide 20 x 5 = 100 by the number of cubic centi- meters used in order to obtain the percentage of sugar in the urine (§ 70, C). Knapp's method is equally accurate (§ 70, 2). The estimation of sugar optically with the polariscope is more quickly accomplished (§ 70, 3). Very satisfactory results are also obtained by the difference of the specific gravity before and after fermentation. (Manas- sein's method, § 70, 5.) 12. Determination of the Albumen (§ 75). The process is carried out just as described in § 75. 13. Determination of the Uric Acid (§ 73). 200 cc. of urine are treated with 5 ec. of hydrochloric acid of I'll sp. gr., covered and left at rest from twenty-four to thirty- six hours in a cool place at a temperature of 10° or 15° C. (in most cases twenty-four hours are sufficient) ; the fluid is then drawn off with a siphon, and lastly the crystals are collected on a small dried and weighed filter. After washing (the drops which come away should not have an acid reaction) it is dried at 100° 0. and weighed (§ 73). 14. Determination of the Kreatinin. We proceed exactly according to § 74, 0. 15. Determination of the Calcium (§ 76, I., 0). 200 cc. of urine are treated with ammonia, the resulting pre- cipitate dissolved in as little acetic acid as possible, and the calcium precipitated with oxalate of ammonium. When the fluid has become perfectly clear it is drawn off with a siphon, the calcic oxalate is collected on a filter, washed, ignited, and titrated with hydrochloric acid and sodic hydrate solution, as described in § 76, C. 1 cc. of saturated hydrochloric acid cor- responds to 10 mgrm. of CaO, or 18-45 mgrm. of SCaOjPOj. 16. Determination of the Magnesium (§ 76, II. 1). a. The fluid obtained in 15 is united with the wash water, and the magnesium is precipitated by ammonia as ammonio- magnesian phosphate. After twelve hours the clear fluid is drawn off with a siphon, the precipitate collected on a filter, washed with water containing ammonia, ignited, and weighed (§ 76, II. 1). Or the phosphate of magnesium is dissolved in acetic acid, and the magnesium determined by titrating the phosphoric acid contained in the precipitate, as described in § 76, II. 2. Digitized by Microsoft® QUANTITATIVE ANALYSIS. 343 b. 200 cc. of urine are preeipitated witli ammonia, tlie earthy phospliates -whicli separate are collected on a filter after a few hours, washed with Water containing ammonia, dried and ig- nited just as we have described in § 76, II. 1, b. The quantity of phosphate of calcium obtained subtracted from the quantity of earthy phosphates found gives as a remainder the quantity of phosphate of magnesium (2MgOP05) which was present. I prefer this second process to the one described under a. 17. Determination of the Ammonia (§ 77). 20 cc. of urine are mixed with milk of lime and placed in the apparatus described and figured in § 77, C, beside a measured volume of standard sulphuric acid, and the non-saturated por- tion of the acid, after forty-eight hours, is titrated back with sodic hydrate of known strength (§ 77, C). 18. Determination of the Iron (§ 72). 200 cc. of urine are evaporated to dryness, ignited according to § 60, until all of the carbon is consumed, dissolved in hy- drochloric acid, the oxide of iron which is formed is reduced by boiling with sulphite of sodium, allowed to cool, diluted to 60 cc, and the iron present determined by a solution of perma- ganate of potassium, whose strength has been ascertained just before using it by a solution of oxalic acid or ferrocyanide of potassium (§ 72). 19. Determination of the Potassium and Sodium. We proceed as in § 79. 20. Determination of the Fat. According to § 82. 21. Determination of the free Carbonic Acid. "We proceed exactly as in § 80. 22. Determination of the Iodine. After the method given in § 71. 23. Determination of the Total Nitrogen contained in the Urine (§ 81). 24 Determination of the Indican (§ 84). 25. Determination of the Oxalic Acid in Solution (§ 85). 26. Determination of BUiary Acids (§ 83). Digitized by Microsoft® 344 ANALYSIS OF TEE UBINE. IV. PRACTICAL GUIDE FOR APPROXIMATE ESTIMATIONS. §91. Although we are able by means of the different volumetric methods to ascertain with certainty and rapidity the quantity of very many constituents of the urine, still cases occur in which the physician wishes to determine immediately whether a urine contains more or less of a certain constituent than has been the case at another time. But since it is not necessary to give a special guide for approximately estimating every constituent, the two methods employed by Beneke * may serve as examples of others. 1. Estimation of the. Earthy Phosphates by the Method of Beneke. The earthy phosphates are known to be held in solution ia the urine by the free acids, and separate when the urine be- comes alkaline. If, therefore, we saturate the free acid of the urine with any alkali, we obtain a precipitate if the urine contains earthy phosphates. According to the amount of the earthy phos- phates in solution there will be either no cloudiness at all or only a very slight one, and sometimes a larger, sometimes a smaller precipitate will result. These differences are charac- teristic enough to enable us to draw an approximate conclusion as to the quantity present. If we always use for such estimations a vessel of the same diameter, which at a certain mark contains exactly 15 or 20 cc, we can, as the large number of experiments performed by Beneke show, soon distinguish quite definitely different de- grees of cloudiness or precipitation. If we first establish a scale for the different degrees of cloudiness which arise, and, secondly, determine by accurate analysis the actual quantity corresponding to each degree of the scale, we have all of the conditions which are requisite for the performance of such an analysis. For estimating the earthy phosphates seven degrees of cloudiness are distinguished by Beneke, and the amount cor- * Beneke, Znr Physiologie und Pathologie des phosphorsauren und oxal- aauren Kalks, GSttingen, 1850. Digitized by Microsoft® PRACTICAL GUIDE FOB APPROXIMATE ESTIMATIONS. 345 responding to these was determined according to the method described in §. 76. Beneke marks : 1. With 0, a urine which, after being boiled in a test tube and treated with 5, 10, or 15 drops of a sodic hydrate solution (one part of sodic hydrate in twelve parts of water), showed no cloudiness, but remained as clear as before. 2. With ^, a urine which when similarly treated showed a slight opacity. 3. With 1, a urine which, treated in the same way, gave a strong opacity, yet of such a kind that objects behind the glass, as, for example, the frames and borders of a window, could be distinguished through it. 4. With 1^, a "urine which, after the addition of sodic hydrate, gave so great a degree of cloudiness, yet still somewhat opa- lescent, that an object behind the glass could scarcely be dis- tinguished. 5. With 2, a urine which becomes very turbid and loses its opalescence. 6. With 2i, a urine which yields a considerable precipitate of earthy phosphates a few seconds after adding the sodic hy- drate. 7. With 3, a urine which immediately gives a large precipitate. 8. With 3 to 4, finally, a urine which separated a very large quantity of earthy phosphates immediately after the addition of sodic hydrate. It is easy to see that we may become so familiar with the dif- ferent degrees of cloudiness by frequent repetition of this sort of test, that a specimen may readily be classified according to the scale. Cases occur, however, in which the appearances do not agree with any one of the given numbers; such may be designated with sufficient accuracy by saying \, J, \\, 1\, etc. If the urine is alkaline any sediment of earthy phosphates which is present is equally divided, one portion of the urine is then boiled, and, according as the alkaline reaction is weak or strong, only a little or none of the solution of sodic hydrate is added. If the urine contains albumen, it is coagulated by boil- ing, filtered, and the filtrate then tested for phosphates. Beneke has found by accurate analysis that the scale he gives corresponds to the following quantities in an ounce of urine ; Digitized by Microsoft® 346 ANALYSTS OF THE UBINE. Urine ke i contains about O'lOO or 0150 grm. of earthy phosphates " i " 0-350 " 0-300 tf 1 " 0-400 " 0-450 ti li " 0-550 " 0-600 t< 2 " 0-700 " 0-750 it 3i " 0-850 " 0-900 (( 3 " 1-000 " 1-050 1 1 3 to 4 " 1-000 " 1-300 •1 _ _1 • ^X_1 _ 1 T_ i. We can thus easily reckon approximately how much earthy phosphates are passed with the u^rine in twenty-four hours. 2. Estimation of the Gcdcic Oxalate by Beneke's Method. To esti- mate the quantity of calcic oxalate approximately, Beneke used a method similar to the one just described, which, in brief, is as follows : In testing for calcic oxalate it is necessary, on each occasion, to allow a portion of the urine under investigation to stand twenty-four hours in a test tube. If at the end of this time a sediment has formed in the lowest part of the glass, the clear fluid is poured off and one of the last drops examined un- der the microscope. This test must not be omitted, even if no distinct cloudiness is observed in the specimen. If we find a sediment of urates, the drop is warmed on the glass slide to dissolve the urates, and the calcium phosphate is removed by a drop of acetic acid, when the calcic oxalate will remain behind alone in most cases. By operating in this way, by always exam- ining only one drop of the sediment on the slide, and by cover- ing the drop with a thin covering glass, we will be able to decide as to the quantity of calcic oxalate present. To get a better idea, Beneke has here, also, distinguished the different quantities with numbers : Urine marked contains no calcic oxalate. " i " very little calcic oxalate. „ 1 little " li '• a moderate amount of caJcic oxalate. " 3 considerable " " " 3J " much " " " 3 to 4 " an exceedingly large quantity of calcic oxalate. Since it is quite apparent that each person must make such a scale for himself, I content myself with having brought forward these two methods of Beneke, similar to which others may be easily arranged for albumen, uric acid, sulphuric acid, etc. Such approximate estimates, however, can lay no claim to great accuracy. Digitized by Microsoft® ANALYTICAL EXPERIMENTS. ANALYTICAL EXPERIMENTS. §92. 347 I. Tahhfor Estimating the Toted Solids from the Specific Gravity (§ 59, 3). SPECII'IC GEAVITT. SOLIDS FOUND BY WEIGHING. SOLIDS CALCULATED BY MULTIPLYING BY 0-233. PER THOUSAND. PER THOUSAND. 1-0160 37-4 37-28 i-oaao 62-0 60-58 1-0154 35-1 35-88 . 1-0261 60-2 60-81 1-0213 48-6 49-63 1-0230 56-4 53-59 1-0230 56-0 53-59 1-0225 49-3 52-42 1-0240 54-1 55-92 1-0257 60-4 59-88 1-0275 63-9 64-07 1-0275 64-2 64-07 1-021.7 48-5 50-56 1-0223 52-15 51-96 1-0140 31-08 32-62 1-0236 56-64 54-98 1-0133 30-87 30-99 1-0134 31-06 31-22 1-0238 57-09 55-45 1-0250 60-47 58-25 1-0164 37-26 38-21 1-0135 33-35 31-45 1-0210 48-54 48-93 1-0137 32-55 31-92 1-0085 19-16 19-80 1-0110 24-96 25-63 1-0200 Average 46-59 46-52 Digitized by Microsoft® 348 ANALYSIS OF THE URINE. From these determinations we find that by dividing the mean quantity of solid constituents found in 1,000 grm. of urine by the last three decimals of the mean sp. gr., we obtain the quo- tient 0"23295, for which we may conveniently put down the num- ber 0-233, as Haser suggests. By multiplying with this quotient the three last decimals of the sp. gr. carried out to four places of decimals, we obtain the figures given in the third column, whose difi'erence from those obtained by gravimetric analy- sis may be seen in the above table. If, however, the specific gravity has been determined only to three decimals, the second and third figures multiplied by 2-83 give, approximately, the amount of solid matters in 1,000 parts of urine. II. Determination of the CMorine (§ 66). The comparative analyses were carried out according to the following methods : a. 5 CO. of urine were evaporated with nitre, the organic mat- ters destroyed by ignition, and the chlorine determined by a solution of nitrate of silver. b. 5 CO. of urine were heated with different quantities of per- manganate of potassium solution (four grm. to the liter), and the chlorine in the filtrate titrated with nitrate of silver solution. c. 5 cc. of urine were diluted with 10 cc. of water, and the chlorine directly titrated with a solution of nitrate of silver. 1st Series. Mioced urine of twenty four hours. ( 7'5 per thousand of NaCl. 1. According to a there were found •] 7'6 " " { 7-6 3. According to 1), 5 cc. of urine with 10 cc. of permanganate solution 8 '8 per thousand of NaCl. 5 cc. " " 20 cc. " " 8-8 " " 5 cc. " " 30 cc. " " 8'5 " " 5 cc. " " 40 cc. " " 8.3 " " 3. According to c there were found 9 -3 to 9-4" " 2d Series. The mixed tweniyfour hours^ urine. 1, ,. , ,, . ,(61 per thousand of NaCl. 1. According to a there were found •] „.., ,, ,, 3. According to b, K „ „ . -xt, oA j^ i , i. ( 6'4 per thousand NaCl. 5 cc. of urine with 30 cc. of permanganate solution J .J' ,^ ,, Digitized by Microsoft® ANALYTICAL EXPERIMENTS. 349 5 oc. of urine with 30 cc. of permanganate solution \ ^'^ P^"^ thousand NaCl. ' 6-3 (A slight excess of permanganate must be destroyed by a few drops of oxalic acid solution.) 3. According to c there were found 6-6 to 6-8 per thousand of NaCl. 3d Series. Concentrated morning urine. 1. According to a there were found \ *'^ P®^ thousand of NaCl. ( 4-6 " " 2. According to b, K „„ „* „^ „5*i, en »» c .1 n i- ( 4-9 per thousand of NaCl. 5 cc. 01 unne with 50 cc. of permanganate solution ■] , _ „ (A slight excess of permanganate must be decomposed by a few drops of oxalic acid solution.) I 5 8 per thousand of NaCl. 3. According to c there were found ■] 5-7 " " ( 5-7 The procedure a, therefore, yields the most accurate results. III. Determination of the Phosphoric Acid. With oxide of uranium solution (§ 67). Tlie titration was performed according to tlie directions given above for every 50 cc. of urine ; the gravimetric estimation, on the other hand, for every 100 cc, according to the ordinary method and with the observance of all requisite precautions. The ammonio-magnesian phosphate before ignition was mois- tened with a few drops of a concentrated solution of nitrate of ammonium, and thus the phosphate of magnesium obtained perfectly white. It gave the following results : Volumetric Analysis. Gravimetric Analysis. 100 cc. 0-1302 0-1303 0-1399 100 cc. 0-2352 0-2343 100 cc. 0-1889 (01383 (01410? 100 cc. 0-1312 01318 0-1324 rV. Determination of the Sulphuric Acid ( § 69). The sulphuric acid in each 100 cc. of urine was determined by weighing and by the volumetric method, and the following results obtained : Digitized by Microsoft® 350 ANALT8I8 OF THE UBINE. Gravimetric. 0139 grm. SO3 0-183 " " 0-374 " " 0-139 " " 0-335 " " Volumetric. 0-138 grm. SO3 0-177 " " 0-370 " " 0-137 " " 0-338 " " V. Determination of Sugar (§ 70). 1. 0-4 grm. of pure grape sugar was dissolved in 20 cc. of urine and diluted to 100 cc. ; the urine consequently contained 2 per cent, of sugar. 12-3 cc. were required to reduce 10 cc. of the copper solution. There were found, therefore, 5x5 13-3 =2-03 per cent. 0-6 grm. of grape sugar was dissolved in 20 cc. of urine and diluted to 100 cc. ; the urine, therefore, contained 3 per cent, of sugar. 8-4 cc. were required to reduce 10 cc. of the copper so- lution. There was found, therefore, 5x5 3 -97 per cent. 2 grm. of grape sugar were dissolved in 20 cc. of urine and diluted to 400 cc. ; the urine then contained 10 per cent, of sugar. 10-5 cc. were required to reduce 10 cc. of the copper solution. There was found, therefore. 20x5 10-5 : 9 -5 per cent. 2. Comparative experiments with diabetic urine carried out by the methods of Fehling, Knapp, and optically with the Ventzke-Soleil apparatus, gave the following results : a. According to Fehling's method . . . . 3-59 per cent Knapp's " . . 3-68 " By circumpolarization . . . . 2-40 « b. According to Fehling's method . . . . 3-67 " Knapp's " . . . . 3-47 " By circumpolarization . . . . 2-10 " Digitized by Microsoft® AWALYriOAL EXPEHIMENTS. 351 VI. Ddermination of the Kreatinin (§ 74). 0-8938 grm. of kreatinin, tlie purity of which was proTed by estimating the nitrogen, were dissolved in 2 or 3 cc. of water and diluted to 160 cc. with absolute alcohol. Each 50 cc. of this solution, in which 0'2793 grm. of kreatinin was dissolved, were measured off and precipitated by adding J cc. of an alcoholic so- lution of chloride of zinc of 1'195 sp. gr. After standing forty- eight hours in a cool place the resulting precipitate was care- fully collected on a weighed filter, and dried at 100° C, the filtrate first obtained always being used for collecting the pre- cipitate on the filter. The washing with absolute alcohol was only commenced when the mother liquor had completely run off. When dried at lOO'' the following results were obtained : 1. 0"2793 grm. of kreatinin gave 0"4438 grm. of kreatinin chlo- ride of zinc corresponding to 99*2 per cent. 2. 0"2793 grm. of kreatinin gave 0'4429 grm. of kreatinin chlo- ride of zinc corresponding to 99 '0 per cent. 3. 0*2793 grm. of kreatinin gave 0'4439 grm. of kreatinin chlo- ride of zinc corresponding to 99 "2 per cent. As an additional measure an estimation of the nitrogen was made with bhe kreatinin chloride of zinc obtained from the alcoholic solution: 0-3453 grm. dried at 100° C. gave 0-0798 grm. of N ; corresponding to 23-1 per cent of N, while the cal- culation required 23-21 per cent. 100 parts of kreatinia chlo- ride of zinc dried at 100° 0. correspond, therefore, to 62-44 per cent, of kreatinin. From the above calculations it appears, therefore, that the estimation of kreatinin with chloride of zinc nearly equals in accuracy the estimation of potassium with platinic chloride. "VTI. Determination of the Albumen (§ 75). Double analyses by weight were very carefully made with clear filtered urine containing a solution of albumen. 1. a. 100 cc. gave 1-130 grm. of albumen dried at 100° 0. b. 100 cc. 1-107 " a. 100 cc. 0-624 " b. 100 cc. 0-616 " a. 100 cc. 0-600 " b. 100 cc. 0-588 " VIII. Determination of the Calcium (§ 76). 0-222 grm. of calcic phosphate were converted into carbonate Digitized by Microsoft® 352 ANALYSIS OF THE TJRINE. according to § 76, 1, and then dissolved in 20 cc. of hydrochloric acid, 1 cc. of which corresponded to 10 mgrm. of CaO. 10'2 cc. of sodic hydrate solution of corresponding strength were re- quired for titrating back; consequently 20 — 10'2 = 9'8 cc. of hydrochloric acid were saturated by the lime. The 0'222 grm. of calcic phosphate contained, therefore, 0'098 grm. = 44"14 per cent, of CaO. The gravimetric estimation gave 44"20 per cent, of CaO. Each 100 cc. of the same urine treated by this method gave a percentage of 0'0420 and 0423 of lime. IX. Determination of the Ammonia (§ 77). The sulphuric acid employed in these experiments contained 0'5304: grm. of SO3 in 10 cc, corresponding to 0*22542 grm. of NH3. 22 "1 cc. of solution of sodic hydrate were required to saturate 10 cc. ; 1 cc. of sodic hydrate solution, therefore, cor- responded to -»-|i?y*-^ = 0-0102 grm. 'SB.,. 1. 10 cc. of urine were directly treated with milk of lime. After forty-eight hours the NH3 evolved corresponded to 0'8 cc. of the sodic hydrate solution. Consequently the urine con- tained 0"081 per cent, of NH3 2. 40 cc. of the same urine were freed from the coloring and extractive matters by 40 cc. of the mixture of the acetate and basic acetate of lead solutions. 20 cc. of the clear filtrate, cor- responding to 10 cc. of urine, after forty-eight hours had evolved the same quantity of NH3 ; 0"8 cc. of the sodic hydrate solution was saturated. After another forty-eight hours the two specimens had evolved no more NH3. 3. To 10 cc. of the same urine 0"2343 grm. of chloride of ammonium dried at 100^ C. were added. At the end of the experiment 14 ■! cc. of the sodic hydrate solution were required to saturate the 10 cc. of sulphuric acid. The NHj evolved cor- responded, therefore, to 22-1 — 14-1 = 8 cc. of sodic hydrate solution. The 10 cc. of urine alone corresponded to 0'8 cc. of sodic hy- drate solution ; there remains then 8"0 — 0'8 = 7'2 cc. of sodic hydrate solution for the chloride of ammonium added. 7 "2 cc. of sodic hydrate correspond to (7"2 x 0-0102) = -07344 grm. NHj, and this (17 : 63-46 = 00-07344 : x) = 0-2309 grm. of chloride of Digitized by Microsoft® ANALYTICAL EXPEBIMENTS. 353 ammonium. Thus 0'2309 grm. were found again for the 0'2343 grm. added. 4. 10 cc. of another specimen of urine were treated directly with milk of lime. The NH3 evolved corresponded to 1'25 cc. of sodic hydrate. So that the urine contained 0"1275 per cent, of NH,. After another forty-eight hours no more NHj was evolved. 5. 10 cc. of the same urine were treated with 0'1744 grm. of chloride of ammonium. After th^ end of the experiment 15"4 cc. of sodic hydrate were required to saturate the 10 cc. of SO3. The ISTHj evolved, therefore, corresponded to 221 — 15'4 = 6'7 cc. of sodic hydrate. The 10 cc. of urine alone corresponded to 1-25 cc, and thus there remained 6"7 - 1'25 = 545 cc. of sodic hydrate for the chloride of ammonium added. 5"45 cc. correspond to (5-45 x 0-0102) = 0-05559 grm. of NH^, and this to 0-1747 grm. of chloride of ammonium. Instead of the 0-1744 grm. added, then 0*1747 grm. of chloride of ammonium were found. 33 Digitized by Microsoft® Digitized by Microsoft® PART SECOND. THE SEMIOLOGY OP HUMAN URINE; OB, THE ESTIMATION AND SIGNIFICANCE OP THE CHANGES OF THIS FLUID : TOGtETHEE WITH A GUIDE TO THE EXAMINATION OF URINAET CALCULI AND OTHER URINARY CONCRETIONS, -PITH SPECIAL REFERENCE TO THE PURPOSES OP THE PRACTISING PHYSICIAN. BY JULIUS VOGEL. Digitized by Microsoft® Digitized by Microsoft® rNTEODUCTION. The study and analysis of the urine has been regarded from the earliest times as of great assistance in recognizing and form- ing an opinion concerning diseased conditions. Nevertheless, before the chemical and microscopic methods of examination were perfected, the real value of this branch of science was slight, and the inspection of the urine, often misused by charlatans to deceive an ignorant public, consequently for a long time fell into discredit both with scientific physicians and the educated portion of the public* With the improvement of organic chem- istry and the general use of the microscope, uroscopy first as- sumed a scientific character, and no one now doubts that it is entitled to form an important and essential part of semiology and diagnosis. Many important diseases are distinctly recognized and accurately determined only by an examination of the urine : thus the different forms of diabetes, most kinds of nephritis, etc., many conditions dangerous to the health, can only be warded off by observing the changes of the urine, such as the risk of the formation of a calculus, etc. The aid which an examination of the urine renders the physi- cian in reference to diagnosis, prognosis, and treatment may be of two kinds. An examination of the urine enables us to draw conclusions ; * Unfortunately this method of inspecting urine practised by charlatans threatens to crop out again at the present time. The author has had frequent opportunity to convince himself of this ; indeed, it is not merely uneducated persons belonging to the lowest classes of society who allow themselves to be deceived by such "marvellous doctors," but also people who belong to the higher and especially "educated" masses. Under such circumstances it doubly be- comes the duty of physicians to point out to the public what aid a scientific study of the urine can furnish in the diagnosis, prognosis, and treatment of dif- ferent diseases. 357 Digitized by Microsoft® 358 INTRODUCTION. 1. As to the general conditions of the economy, the relations of metamorphosis, character of the blood, the digestion, etc. 2. As to certain local diseases of organs belonging to the uro- potitic system. In the following pages we shall as far as possible consider both of these points equally. Moreover, the examination of the urine may sometimes give information concerning special facts and processes which pos- sess a certain importance for the physician. Thus we are fre- quently able from the mere inspection of the urine to determine whether a patient has a fever or not. From the odor or the color of the urine we know that certain articles of food or medi- cine have been taken, for example asparagus, oil of turpentine, rhubarb, etc. From the appearance of spermatozoa in the urine we know that a masturbation or coitus has taken place ; from the presence of albumen in the urine we can conclude under certain circumstances that the patient is dropsical ; or when the urine contains biliary coloring matters that jaundice exists, etc. The crafty physician makes use of such indications to gain the confidence of his patient in his knowledge or to re- tain it ; but the scientific physician will avail himself of them cautiously and without ostentation, since any misuse of such means stamps him as a charlatan in the eyes of his colleagues and of the public. In many cases an examination of the urine is of great im- portance to therapeutists, since it proves whether certain sub- stances which a patient has used as medicine are eliminated again with the urine or not. In the latter case the physician is cautioned that by a continued use of many medicines he may readily produce a so-called cumulative action in the system which is dangerous, as is the case with nitre, digitalis, strychnia, etc. In the former case, on the other hand, he will be prompted to continue the agent, or even to increase the dose, when it is desirable to keep the system to a certain degree saturated with it for a long time, so that it may have its complete effect slowly and gradually, as with iodide of potassium, alkaline carbonates, and the like. The importance of examining the urine for such purely therapeutical purposes has not been hitherto sufficiently valued in practice. Its application, however, will surely in- crease in proportion as the analytical processes necessary to Digitized by Microsoft® INTBODUGTION. 359 carry it out, now difficult and incomplete, are further perfected, simplified, and rendered easy for tlie physician — a problem whose solution the author would most earnestly recommend to those chemists who are interested in the subject. If the science of urinary examination in reference to the above point has been hitherto neglected, there are, on the other hand, other points in regard to which its value has been overestimated. Many special facts will be mentioned later in this connection. One erroneous opinion, however, which is based on an imperfect knowledge of the nutritive changes in disease and upon an ontological way of regarding single forms of disease not yet discarded by all pathologists, deserves men- tion and a refutation, because it and the conclusions drawn from it have a very great range and are widely spread, and have even appeared anew in recent works on these subjects. It is, the opinion that the different forms of disease are charac- terized by a definite condition of the urine which corresponds to each. This statement is only true for a very few diseases, in which a certain condition has received its name from a char- acteristic condition of the urine. It is natural that the urine in albuminuria should contain albumen, in hsematuria blood, in glycosuria sugar, in oxaluria oxalic acid, etc. ; if this were not the case, we should not be justified in giving this name to the disease. In other forms of disease we only very rarely find any specially characteristic condition of the urine; and when recently it has been several times asserted that the urine, for example, in typhoid fever, pneumonia, etc., has possessed a cer- tain composition or qualities, such observations, as a rule, rest on insufficient data or the investigations have been made in certain stages of these diseases only. Examinations of the urine in the above diseases in which they have been made in great number and in all stages of the disease show, as will be proved later, that the condition of the urine in aU acute diseases changes with the progress of the disease, with a certain degree of regularity. And that this change in the con- dition of the urine ordinarily depends less on the special nature of the sickness, especially its local phenomena, than upon cer- tain general conditions of the body, such as the intensity of the fever, the state of the appetite and digestion, that is, upon the greater or less amount of food taken. This is also true of Digitized by Microsoft® 360 INTBOBUOTION. chronic diseases in wliich acute exacerbations occur, as is often the case. For example, the wide-spread, idea that the amount of urea in the urine in Bright's disease is diminished is untrue to this extent : that in febrile forms of this disease, just as is the rule in all fevers, an increase of the urea is observed. Therefore, it appeared better to consider in the following pages only the general semiology of the urine, since the special semiology of this fluid, that is, the description of the composi- tion of the urine in individual diseases, is best left to the con- sideration of each disease, that is, to special pathology. To render more easy the general study and the solving of certain questions, the following pages have been divided into two principal divisions and several subdivisions. The first division discusses the qualitative changes of the urine including the sediment. It contains four subvisions : I. Changes in color, appearance, and odor of the urine. II. The chemical reaction of the urine and its significance. in. The occurrence of unusual or abnormal constituents in the urine. IV. Urinary sediments. The second division comprises the quantitative changes of the urine : the increase and diminution of the normal consti- tuents. It is subdivided into two large groups : I. Quantitative changes of the urine which can be determined without chemical analysis, and which, on account of their easy detection, are especially important to the physician. II. Quantitative changes which require a quantitative chem- ical analysis for their demonstration. A guide to the examination of urinary calculi and other uri- nary concretions is added as an appendix. Those who desire to study more minutely the changes of the urine which occur in disease, especially in regard to their di- agnostic significance and the therapeutic indications which they give the physician, are referred to my work on the diseases of the kidneys (including the changes in the urine which occur in gen- eral diseases) in the Handhucli der speciellen Pathologie und Ther- Digitized by Microsoft® INTBODUOTION. 361 apie, Band 6, edited by Virchow, and published by F. Enke in Erlangen. Since the author had in view especially the needs of the phy- sician, it appeared best, owing to the necessity of as condensed a statement as possible, to communicate the results of many labors on human urine during the last few years only so far as they were of interest not merely to chemists and physiologists but to the physician. But to satisfy those who wish to inform themselves somewhat more in detail than the space here per- mits on many points, especially as to questions which are still subjudice, the literature which contained further information in regard to them was referred to. Moreover, to avoid repetition, all which has already been mentioned in the first part has been omitted, and we have only referred to the sections concerned, or to the numbers of the pages. Digitized by Microsoft® •^"^ Digitized by Microsoft® DIVISION FIKST. QUALITATIVE CHANGES OF THE URINE, INCLUD- ING URINARY SEDIMENTS. I. CHANGES IN THE COLOR, APPEARANCE, AND ODOR OF THE URINE. The changes of tlie urine whicli belong under this head are naturally the most easily detected ; but of themselves alone they rarely lead to positive diagnostic and semiotic conclusions. Usually they only serve as hints and guides to a further inves- tigation of the urine by other means. Therefore, the mere in- speotion of the urine without using other additional methods of investigation is of relatively little value to the physician. § 93. Color of the Urine. The color of the urine is due to the coloring matters, whose nature and origin, in spite of numerous investigations, has thus far not been completely explained. For what is known on this point see § 10. We shall only speak of those points here which have an importance to the medical practitioner. (Compare § 122.) The color of the urine is an important sign which sometimes gives the practitioner valuable indications for judging of the condition of a disease ; but still more frequently it may serve to give him a general idea of it, and to point out to him the direction for his further investigations. As practitioners we must distinguish between Tiormal and ab- normal color of the urine. 1. The normal color of the urine is yellow, with a greater or less admixture with red. It varies from almost colorless (like water), through yellow, to red and reddish brown. 363 Digitized by Microsoft® 364 8BMI0L0QT OF HUMAN UBINE. These different shades of color of normal urine may be clas- sified in the following principal groups : Pale — colorless to straw yellow.* Normal — gold to amber yellow.t High color — reddish yellow to red4 Dark — with a brownish tint, dark beer-color to blackish.§ A pah urine contains little coloring matter, little urea, and, as a rule, also only little solid constituents (except diabetes mel- litus). It is seldom very acid, frequently neutral or alkaline. It is observed in persons in perfect health after copious drinking (urina potus), in many who are suffering from chronic diseases (anaemia, chlorosis, diabetes), as well as frequently in convales- cents from severe acute diseases. The existence of a pale urine is an almost absolute indication to the physician that the pa- tient in question does nx)t suffer from a severe acute febrile disease, and a urine which continues to be very pale for a long time always indicates a certain degree of anaemia (oligocythsemia). Normally colored urine only warrants the negative conclusion, that no disease exists which from its nature is characterized by a very pale or very high-colored urine. Sigh-colored urine is generally concentrated, abounds in solid constituents (has, therefore, a high specific gravity), is rich in urea, and usually very acid. It occurs in cases in which the secretion of water by the kidneys is diminished, while the secre- tion of the other constituents of the urine is normal or even in- creased. It, therefore, occurs in perfectly healthy persons after eating hearty meals (urina chyli), or when they have perspired freely and drunk little, as after vigorous exercise. It occurs in almost all febrile diseases, and becomes, therefore, an important sign to the physician. In hectic fevers especially it is often a surer indication than the pulse and the temperature in deciding as to the intensity of a febrile increase of metamorphosis. DarJe urine, as a rule, indicates that an abnormal pigment is mixed with the urine, the determination and significance of which requires a more careful investigation. Occasionally it is desirable to determine the color of a urine * Plate IV., fig. 1 and 3. t Plate IV., fig. 2 to 4. i Plate IV., fig. 5 and 6. § Plate IV., fig. 7 to 9. Digitized by Microsoft® CHANQEa IN COLOR, APPEABANOE, AND ODOS. 365 more accurately than according to the above general categories. We then proceed according to § 61, and make use of the con- siderations mentioned in § 122 for drawing the conclusions therefrom. Heller has given still another method for approximately de- termining the quantity of the ordinary urinary coloring matter named by him urophaein.* A little concentrated English sul- phuric acid is poured into a beaker and about double its quan- tity of the urine to be tested is added. If the mixture is quickly stirred it becomes colored more or less dark brown or tarry black. From the intensity of the color we decide as to the amount of urophaein present. Ziegler states that the most intense color is produced by this test in cases of chronic de- generation of the liver, especially cirrhosis of the liver, and he uses this urophein test as an aid in the diagnosis of this disease. In many cases the color of the urine depends on different pigments which are present at the same time — soluble pigments which are dissolved in the urine, and insoluble ones which ad- here to the sediments. It is, therefore, well to filter the urine in order to be better able to decide as to the part which the different pigments play in coloring the urine. 2. Abnormal color of the urine results from the presence of unusual coloring matters. These unusual urinary pigments may be divided into two groups : a. Essential abnormal colors of the urine, which are formed within the organism as the result of certain pathological pro- cesses, and, therefore, have an important significance for the practitioner. b. Accidental abnormal colors, which get into the body from without, in the food, drink, or medicine, and are eliminated again with the urine, merely passing through the economy. The most important abnormal colors of the urine are : a. The Essential, caused 1. By Blood Pigments. These form very different shades ac- cording as the blood red is dissolved, in combination with the * Compare Ziegler, Die Uroscopie am Krankenbette, Erlangen, Perd. Enke, 1861, S. 34, et seq. Digitized by Microsoft® 3G6 SEMIOLOar OF HUMAN URINE. blood corpuscles, decomposed, unchanged, or present in the urine in greater or less quantity. The shades of color which are thus produced may vary from blood red (bright garnet red) to brown, brownish black, or even to an inky black. For the detection and the significance of this blood coloring matter in the urine, see § 99 and § 100, and the cases 11, 12, and 13 in § 134 2. By Biliary Figrnents. The color of this urine is yellowish green or brownish green. For the details see § 102. 3. By Indican (uroxanthin) and its products of decomposition, uroglaucin and urrhodin. See § 10, page 67, et seq.* Uroxanthin rarely has any appreciable influence on the color of the urine ; it is only in those cases in which, with a defi- ciency of urophaein (urobilin), a large amount of uroxanthin is present, that the urine assumes a lemon-yellow color (in cholera and affections of the spine). To demonstrate the presence of uroxanthin, however, a chemical process is always necessary, as has been described already on page 71, 0. According to Baumstark,t indican belongs with hippuric acid, tyrosin, and the biliary acids in the chemical series of so- called " aromatic compounds," and is probably formed in the liver especially. According to Jaffe's observations the small quantity of indi- can normally present in the urine is increased by a meat diet; it is diminished to a mere trace by a diet containing little nitro- gen ; according to Jaffe and Hoppe-Seyler, it is considerably in- creased in carcinoma of the liver, and also in cholera, according to Jaffe and Wyss. According to Jaffe, diseases which bring about an obstruction of the small intestine (strangulated hernia, incarceration, etc.) very considerably increase the secretion of indican with the urine (ten or fifteen times the normal amount) ; obstruction of the large intestine increases it less, as experiments on dogs proved. In purulent peritonitis also, probably on account of the diminished motion of the small intestines, the indican is in- * Heller, in Ms ArcMv fiir Chemie und Microscopie, 1853, S. 121, et seg. M. Jaffe (Pflilger's Archiv, iii., p. 448, et seq.). Ibid., Ueber den Urspmng des Indicans im Ham, Centralbl. fur d. medic. Wissensohaften, 1872, p. 3. Ibid., Ueber die Ausscbeidung des Indicans unter physiolog. u. patbolog. Verhaltnis- sen, ibid., p. 481, et seq., 497, et seq. •j- Berliner klin. Wocheascbr., 1873, Nr. 4 Digitized by Microsoft® CHANGES m COLOR, APPEABANCE. AND ODOB. 367 ereased. Also in certain diarrhoeas (cholera and cholera mor- bus), but not in catarrh of the large intestine, accompanied by discharges at the same time from the large intestine only. Fever appears to have no essential influence on the amount of indican in the urine. J. Eosenstern* found the quantity of indican in the urine essentially increased in Addison's disease. According to Heller t and his scholars, the amount of indican which can be detected in the urine is, in some degree, a measure of the amount of excitation of the nervous system, especially of the spinal cord (?). It is said to be increased in urina spastica, after too frequent coitus, onanism, etc., also in every irritation of the urinary organs, every acute and chronic disease of the kidney (nephritis, Bright's disease, perinephritis, etc.), and in many general diseases also, as typhoid fever, intermittent fever, cholera, and uraemia. According to observations which E. Lawson (compare § 122) made in Jamaica, the urine of the inhabitants of the tropics is usually rich in indican, even under normal circumstances. Uroglaucin and urrhodin, products of the decomposition of uroxanthin,! occur only rarely in the urine, when it has under- gone decomposition in the bladder, with the production of a large amount of carbonate of ammonium (in cystitis and Bright's disease). It may then, however, give rise to very striking colors of the urine (green, blue, and violet.) Uroglaucin has a blue color, urrhodin a red color, and from a combination of these two with each other, and with the ordinary yellow urinary color- ing matters many various shades of color may be produced. Thus the urine may become green (greenish to beautiful grass green) when blue uroglaucin occurs in a yellow urine. It appears blue when the normal (yellow) coloring matter is want- ing and uroglaucin predominates ; violet, when uroglaucin and urrhodin are present together; reddish, when the latter pre- dominates. Uroglaucin and urrhodin usually form sediments, and, there- fore, we must filter such a urine. Moreover, urrhodin dissolves * Virctow's Archiv, 1873, Ivi., p. 37, et seq. f Ziegler, loc. cit., p. 38. 'f S. Kletzinsky in Heller's Archiv, 1853, p. 414, and Scherer in Ann. der Cliemie und Pharmacie, Band 90, Heft 1, p. 130. Digitized by Microsoft® 368 SEMIOLOaT OF HUMAN UBINE. in ether witli a beautiful carmine red color, uroglaucin dissolves in boiling alcohol with a beautiful blue color. 4. By uroerythrin, which sometimes, when dissolved in the urine, gives it a red color, sometimes when precipitated with sediments of uric acid and u;rates gives them a brick-red or rose- red color. Compare page 73.* The urine presents a very peculiar appearance in the majority of persons who suffer from melanotic cancer. Of the normal color when passed, it gradually becomes brown or even black when exposed to the air. This dark color appears still more quickly when oxidizing substances have been added, as nitric or chromic acid. This proceeds from a peculiar substance characteristic of melanotic cancer — melanogen. This peculiarity of the urine may be rendered serviceable for the diagnosis of melanotic cancer which is concealed in the internal organs, as, for example, in the liver.f b. Accidental. Various coloring matters which enter the body as constituents of food, drink, and medicines may be eliminated again with the urine and color it. We have very numerous in- vestigations on this point,! which, however, are less important to the physician than to the physiologist and chemist. There are two coloring matters which we may speak of here which are also of interest to the physician, since they form constituents of medicines frequently used, and which often pass into the urine and may resemble urine colored by biliary color- ing matter or more especially by blood. These pigments are rlitibarh and senna. Each may color the urine brownish or even a deep blood red. Both can be readily distinguished from the color due to blood by chemical means, however. Urine which is colored by them on the addition of mineral acids becomes brighter, and light yellow, while urine containing blood is not made clearer by the acids, but in fact becomes rather darker. After taking santonin, also, the urine receives a color similar to that produced by biliary matters (saffron yellow or greenish). It may be recognized from the fact that on the addition of an * Heller in his ArcMv, 1853, p 391, et seq. f For details seeEiselt, Prager Vlerteljahresotr., 1858, S. 190, et seq., u. 1863, S. 26, et seq. Bolze, ibid., 1860, S. 140, et seq. Pribram, ibid., 1865, S. 16, etseq. % Compare the investigations of Kletzinsky in Heller's Archiv f . Chemie und Mikr., 1853, p. 184, 311, 338. Digitized by Microsoft® GHANQES IN COLOR, APPEABANOE, ANB ODOR. 369 alkali the yellow or greenish color, according to the amount of santonin present, beomes cherry red or purplish red.* After the use of carbolic acid or tar the urine at times as- sumes a blackish color. (Compare page 74.) § 94. Odoe of the Ueine. The odor of the urine has no great importance for the physi- cian. Many substances which give the urine a peculiar odor en- ter the economy from without, like the accidental coloring mat- ters described in the previous section, and are separated again with the urine. Their presence may be serviceable to the phy- sician as an indication that patients have taken certain articles of food or medicine. In this way the urine acquires a peculiar odor after asparagus has been eaten, a peculiar one (like violets) when oil of turpentine has been taken, or when it has simply been inhaled in large quantity. We may discover the odors of saffron, cubebs, etc., in the urine. It has been asserted by French pathologists (De Beauvais and others) that the peculiar odors of asparagus, oil of turpen- tine, etc., do not appear in the urine in organic diseases of the kidney. However valuable this means of diagnosis might have been in cases of albuminuria in which the other symptoms left it doubtful whether a merely functional disturbance or an or- ganic lesion of the kidney existed, I would, after some experi- ments of my own, advise that it be accepted with caution. I have found twice, for example, that the urine had the characteris- tic odor of asparagus and oil of turpentine in cases of albumi- nuria, when later the autopsy showed at least a partial organic disease of the parenchyma of the kidney. But normal urine has a specific odor which Heller referred to the coloring matter of the urine (urophaein), but which pro- bably depends on various odorous matters, since Stadeler suc- ceeded by distilling the urine in obtaining several volatile acids from it (phenylic, taurylic, damaluric, and damolic acids). (Com- pare § 9.) A preponderance of one or the other of these would probably modify the odor of the urine. The sense of smell is peculiarly affected by a urine which * Walter ff. Smitli, Dublin Quart. Joum., c, p. 263, et seq. 24 Digitized by Microsoft® 370 SEMIOLOGY OF HUMAN URINE. contains mucli carbonate of ammonium, and the " urinous odor " of patients comes cliiefly from this source. § 95. Tkanspaeency of the Urine. The urine is either clear or cloudy. Slight turbidities form a so-called cloud (nubecula), larger ones after standing a long time deposit as a precipitate, and form a sediment. All turbi- dities of the urine consist of solid particles which are not dis- solved but are only suspended in it. They are either already contained in the fresh urine, or form in it a longer or shorter time after it is passed from the bladder. A normal specimen of urine is always clear or at most has only a very slight degree of cloudiness. Distinct turbidity of the urine always allows us to conclude that there is some abnor- mal condition, and must, therefore, arouse the attention of the physician. But the significance of the turbidity only becomes clear, when we have ascertained its nature. (For further details, see Division IV. under Urinary Sediments.) II. CHEMICAL BEACTION OP THE UEINE. §96. Normal urine almost always has an acid reaction ; that is, it colors blue litmus paper red. Sometimes, however, its reaction is neutral or even alkaline ; in the latter case it renders I'ed lit- mus paper blue. It is most convenient in testing the reaction of urine to use a blue litmus paper, which has a very slight red tint. This serves equally well for detecting an acid as well as an alkaline reaction, since it is rendered more red by acid and deep blue by alkaline urine. It is, moreover, very sensitive. It is prepared by allowing an aqueous tincture of litmus to stand until it becomes slightly acid, and its intense blue color has assumed a reddish tint. Ordinary smooth writing paper is dipped in this tincture and dried in the shade. Sometimes urine is met with which has both an acid and an alkaline reaction ; that is, at the same time it slightly reddens blue litmus paper and blues slightly reddened paper. (Amphi- Digitized by Microsoft® CHEMICAL REACTION OF TEE UBINE. 371 genous reaction of Heller, or better, amplioterous reaction of Bamberger.) This paradoxical phenomenon is probably to be explained as follows : When acid phosphate of sodium is neutralized by ammonia, a compound results (ammonio-sodic phosphate) which has the property of giving off ammonia when it is warmed and the pressure on it is diminished, while acid phos- phate of sodium remains. If, now, ammonia is developed by the decomposition of urea in a urine naturally acid from the presence of acid phosphate of sodium, it may be unequally dis- tributed in the fluid and render certain portions alkaline, or it may form an ammoniacal atmosphere above the fluid by which red litmus paper is made blue, while other portions of the same urine still contain acid phosphate of sodium, and, therefore, redden blue litmus paper. In the same manner we often ob- serve that a specimen of urine which is commencing to evolve ammonia, but which still has a slightly acid reaction, has on its surface a pellicle of crystalline ammonio-magnesian phosphate, which according to its chemical properties cannot exist in an acid fluid.* The chemical reaction of the urine gives the physician sev- eral useful indications, and is, moreover, a test very easy to perform. It is, therefore, a valuable sign in semiology ; and in order to render its importance clear we must study this sub- ject further. Normal urine has an acid reaction. It is not yet positively known on what acid this reaction of the urine depends. It is probable that it depends only in the rarest cases on the pres- ence of a free acid (compare page 6 and § 11)^ but, as a rule, rather on the acid salts ; indeed chiefly on the acid phosphate of sodium, and, perhaps, at the same time in many cases, on acid urates, hippurates, lactates, etc. H. Baysson,t however, believes that the acid reaction of the urine does not depend on acid phosphates of the alkalies, but upon uric, carbonic, and hippuric acids, since uric and hippuric * See further concerning tlie so-called amplioterous reaction : W. Heintz, Journ. f . praJit. Chemie, 1878, vi., p. 274, et seq. f Etude sur les causes de la reaction acide de I'urine normale chez I'homme et de sa variation, Journ. de I'anat. etphysiol., par. Ch. Kobin, 1873, t. viii., p. 383, et seq. Digitized by Microsoft® 372 SEMIOLOQT OF HUMAN URINE. acids are not capable of decomposing neutral phosphate of so- dium at ordinary temperatures. There are, howeyer, two essentially different ways in which the acid reaction of the urine may be lost or even changed to the alkaline. 1. Carbonate of ammonium may be formed in the urine after it is secreted ; the urine then becomes neutral if the quantity of carbonate of ammonium is small, alkaline when it is greater. This development of carbonate of ammonium is caused by a decomposition of urea, which under certain circumstances be- comes converted into carbonate of ammonium by absorbing water. 1 equivalent of urea O2 H4 Nj Oj 4 " "water H4 O4 0, Ha N, Oe = 3 equivalents of carbonate of ammonium = 2 (OOa + NHiO). This conversion of urea into carbonate of ammonium is caused by the presence of a ferment. It was formerly the opinion that the mucus of the urinary passages constituted this ferment. Recent investigations, how- ever, make it probable that it consists of microscopic germs, which decompose the urea by their development in the same way that yeast decomposes sugar in the alcoholic fermentation. Since the spores of this ferment are contained everywhere in the air on account of their extreme minuteness, they can very readily get into the urine. (Compare pages 7, 9, and 188.) Under favorable conditions the urine may become alkaline while still within the urinary passages ; it is then alkaline when passed. The urine thus becoming ammoniacal within the urinary pas- sages has a very great practical importance, because it may be followed by very bad results : irritation of the mucous mem- brane of the urinary passages, blenorrhoea and even gangrene, formation of urinary concretions and ammonsemia. It is, there- fore, very important to the physician to prevent it as much as possible and to remove its cause. Various recent observations have shown that these spores may enter the bladder on a catheter which is not perfectly clean, and to which the above- mentioned ferment may adhere. In the bladder they develop Digitized by Microsoft® CHEMICAL BE ACTION OF TEE UBINE. 373 further and cause the decomposition of urea there.* The prac- tical rule follows, therefore, that every catJieter must be most care- fvlly cleaned before being used. Again, the alkalinity may appear only after the urine has been passed ; it then has an acid reaction immediately after being passed and becomes alkaline only after a time. Almost every specimen of urine becomes alkaline in a longer or shorter time, but in normal urine this alkalinity occurs very late, at any rate not before twenty-four hours have elapsed. When, therefore, urine is evacuated in an alkaline state, or if it is acid when passed and becomes alkaline within twenty-four hours after- ward, we may conclude that there are circumstances present which favor decomposition of the urea, and the physician is jus- tified in drawing diagnostic conclusions from this circumstance. But one circumstance is to be taken into consideration which, if it is overlooked, may lead to error. Wlien urine which has already become alkaline is added to normal urine, the latter undergoes the ammoniacal fermentation much quicker than it otherwise would. This is the case when the urine is kept in a vessel which contains any remains of ammoniacal urine. When the physician, therefore, would draw conclusions from the fact of urine having become rapidly alkaline, say within twenty-four hours, he must be certain that it was kept in a perfectly clean vessel ; he must, therefore, see that the chamber vessels and urine glasses of the patient are not merely emptied, but are also washed out, so that every trace of the ferment is removed. Urine which has been rendered alkaline by carbonate of am- monium colors red litmus paper blue, but after the paper has become dry and the carbonate of ammonium has volatilized, while the acid salts of the urine remain behind, the blue litmus paper becomes red again. Moreover, a glass rod moistened with hydro- chloric acid and held over such a urine develops a cloud of chloride of ammonium. This fact is important, because it serves to distinguish the alkalinity of the urine caused by car- bonate of ammonium from that resulting from other causes. V. Feltz and E. Eitter, professors at the academy of medicine in Nancy,t have arrived at the following results from their in- *S. Fischer, Berliner klin. Wochenschr., 1864, 3. Teuffel, ibid. 16. f Etude experimentale sur Talcalimte des urines et sur rammoniemie, im Joum. de I'anat. et physiol., par Ch. Robin, 1874, Nr. 3, p. 311, et seq. Digitized by Microsoft® 374 SEMIOLOQY OF HUMAN URINE. vestigations : Unclean vessels are often tlie cause of urine be- coming quickly ammoniacal, as in typhoid-fever patients in summer. The urine of women, which contains mucus from the vagina (in fluor albus) or menstrual blood, readily becomes alkaline. The ammoniacal fermentation is caused by a ferment, which may be readily obtained artificially on a filter through which ammoniacal urine has been passed. If this ferment is artificially added to normal urine, it has the power of setting up ammoniacal fermentation in it. However, all urines are not rendered ammoniacal with equal readiness by the addition of the ferment. By prolonged retention in the bladder alone (in animals whose urethrse were artificially closed) the urine is not rendered ammoniacal. The mere passing of a catheter im- pregnated with the ferment does not always certainly render the urine in the bladder ammoniacal. 2. There is still another cause essentially different from the one just described which may render the urine neutral or alka- line. This cause lies in the condition of the blood. Under ordi- nary circumstances acid urine is secreted from the alkaline hhod. The kidneys or their secreting cells must, therefore, have the power of separating acid salts from the alkaline blood, or of forming them and passing them on into the urine.* But when the blood is excessively alkaline, as a rule, acid urine is no longer separated from it, but neutral or alkaline. Thus the urine becomes alkaline when a large quantity of caustic alka- lies or of carbonates of the alkalies are taken into the system, and it continues so until the excess is separated from the blood. Caustic soda, lime, potash, and magnesia, and their carbonates, *[Dr. Richard Maly (Berichte der deutscten chemisclien Gesellschaft, 1876, page 164) has partially explained by some diffusion experiments the acidity of normal urine. He found that by placing in a diffusion apparatus a mixture of the mono-sodic (acid) and di-sodic (alkaline) phosphates of sodium, the acid phosphate passes through the membrane much more readily than the alkaline, so that while the fluid in the dialysor has an alkaline reaction, that without has an acid one. This is virtually what takes place in the kidney. The blood con- tains both of these phosphates of sodium, the di-sodic phosphate being con- stantly deprived of a part of its sodium by uric, hippuric, lactic, and other acids, which are produced by the metamorphosis of the nitrogenous tissues. The mono-sodic phosphate thus formed then readily diffuses from the blood to the urine, and imparts its acid reaction to that fluid, while the principal part of the di-sodic phosphate remains in the blood. — Beviser's Note.] Digitized by Microsoft® CEEMIOAL BEAOTION OF THE URINE. 375 act in this way; further, all vegetable salts, which are converted in the body into carbonates and are eliminated as such in the urine (acetates, citrates, malates, and tartrates). All of these drugs, when they are taken in large doses as medicines, render the urine alkaline, and often in a very short time. Bence Jones found that 120 grains of dry tartrate of potassium dissolved in four ounces of water made the urine alkaline in thirty-five minutes ; two hours later the alkaline reaction had disappeared again. Smaller doses, which are not sufficient to render the urine alkaline, at least diminish its quantity of acid. Food acts in the same way, and according to the nature of its constituents sometimes increases the alkalinity of the blood and sometimes diminishes it. It is known that the urine of carnivorous animals is acid for this reason, and that of herbivo- rous animals is alkaline. A similar action of food on the urine is shown in man, though usually in a less degree, because his diet is in most cases a mixed one. But certain processes in the organism also, results of the secondary metamorphosis, without doubt exercise an influence on the reaction of the urine by changing the alkalinity of the blood. The nature of these processes is, however, very obscure at present, and it is only by very difficult and complicated in- vestigations that we can clear them up. In the meantime the following conditions may be designated as probable : a. Bence Jones has pointed out that the acid reaction of the urine increases and diminishes inversely with the secretion of the acid gastric juice. He asserts that the urine is most acid at the time when the stomach contains no gastric juice, or when this secretion has been returned again to the body ; and that, on the other hand, it becomes less acid or even alkaline in pro- portion as the acid gastric juice is separated from the blood. Unfortunately, the experiments performed by Bence Jones to prove this point are not convincing. In these, as in almost all of his quantitative examinations of urine, the amount of acid is reckoned for 1,000 parts of urine and not for the hourly secre- tion, as should be the case if trustworthy conclusions are to be drawn from them. Experiments which were performed partly by myself and partly by others under my direction invariably showed that the greatest quantity of acid passed with the urine per hour was in the night, the least was during the hours be- Digitized by Microsoft® 376 SEMIOLOGY OF HUMAN URINE. fore noon ; while the quantity of acid in the afternoon hours (after the chief meal) was a mean between the two. These ex- periments, therefore, do not agree with the statements of Bence Jones, but they do not positively contradict them, since other circumstances may influence the amount of acid in the urine. Theoretically Bence Jones's hypothesis appears to be very plausible : a quantity of acid is separated from the blood with the gastric juice, the blood becomes more alkaline, and conse- quently the urine secreted at this time contains less acid. It is possible, however, that the alkali which was combined with the acid of the gastric juice does not remain in the blood, but passes over into the bile, so that the alkalinity of the blood suffers no change through the secretion of the gastric juice, and consequently the secretion of the gastric juice has no influence on the acidity of the urine. Eecent investigations of W. Eoberts have confirmed the statements of B. Jones. (Compare § 127.) b. According to the investigations of Liebig and others, the muscular juice is acid, or at least it becomes so immediately after being expressed. Now since the urine of carnivorous ani- mals is rendered acid by the constituents of the meat which they take as food, it is probable that in man (and in animals) a part of the acid of the urine, perhaps the greatest part, is de- rived from the muscular juice produced by metamorphosis and passed into the blood, or, in other words, the acid of the urine is in part a product of the metamorphosis of the muscular tissue. That this is the case is indicated by the observation which has often been made, that in herbivorous animals which gene- rally secrete an alkaline urine, it becomes acid when they starve, that is, consume the constituents of their own bodies. However, this is not the place to discuss these difficult theo- retical questions. From the physician's standpoint the follow- ing are the chief points of interest in the reaction of the urine : 1. The urine has an cund reaction. This is the normal con- dition, and has only a negative value for the practitioner, since he determines from it the absence of certain diseased condi- tions. Further conclusions are obtained in this case, when the amount of acid has been accurately determined quantitatively (§ 127). A very acid condition of the urine may favor the for- mation of certain sediments or concretions, especially uric acid. Digitized by Microsoft® CHEMICAL REACTION OF TEE UBINE. 377 or it may giTe rise to an irritation of the kidneys and urinary passages. 2. The urine has a neutral or alkaline reaction. This condi- tion is always of importance to the physician, and requires an accurate investigation. In such a case we must regard the fol- lowing particulars : a. The alkaline reaction may depend upon carbonate of am- monium (red litmus paper becomes blue when dipped in the urine, but after drying it becomes red again, and a glass rod moistened with hydrochloric acid and held over the urine de- velops a white cloud). This always comes (except in the rare cases where the carbonate of ammonium is directly eliminated with the urine) from the decomposition of urea in the already secreted urine ; or, b. The alkaline reaction depends upon a fixed alkali, potash, soda, or an alkaline earth (red litmus paper is made blue by the urine and remains so even after drying, and a glass rod dipped in hydrochloric acid and held over it does not show a white cloud). The cause in this case may be : The medicinal use of caustic or carbonated alkalies, or of alkaline salts of the vegetable acids, or a diet rich in the latter, or alterations in the metamorphosis, which was briefly referred to above. The answer to the question as to how far the physician must regard a neutral or alkaline condition of the urine, that is, more especially in reference to his prognosis and treatment, depends chiefly on whether this condition of the urine is temporary or permanent. If the urine has only a transient neutral or alkaline reaction at a certain time of the day, more especially a few hours after eating, after certain kinds of food, or on certain days, it has a physiological but no practical signification. If, however, the urine is frequently or permanently alkaline, important semiotic and practical conclusions may be derived from it, which are diff'erent in different cases : 1. The cause is a decomposition of the urea within the uri- nary passages. The diagnosis of these cases is made from the fact that the urine is ammoniacal, and contains mucus and crys- tals of ammonio-magnesian phosphate. 2. If the cause lies in the continued use of caustic alkalies, Digitized by Microsoft® 378 SEMIOLOGY OF HUMAN UBINE. their carbonates or vegetable salts, the diagnosis is self-evident from the above. 3. The cause consists in alterations of the metamorphosis. These are thus far only imperfectly understood ; but we may designate as probable : arrest of the muscular metamorphosis, -weakness of the nervous system, anaemia and chlorosis, defective nutrition, and general debility. One of the greatest services of Eademacher * is that he called attention to the fact that a con- stantly alkaline urine is an iron affection, that is, translated into scientific language, requires the use of tonic remedies. Still, from what has been mentioned above, it is evident that this is true only in a limited sense, and, moreover, the pale color of the urine in such cases forms a surer indication for the careful observer that tonic remedies are indicated than the al- kalinity of the urine, which is often absent in such cases. The rational treatment of such conditions is frequently very difficult. The chief task is always to discover and combat the cause of the alkalinity. It is a very bad practice, and the re- sult of erroneous chemical reasoning, to give acids in all cases in which the urine is alkaline. When the alkaline state of the urine depends on an irritation of the urinary, passages, which is brought about by a too acid and irritating character of the urine with the formation of uric acid gravel, on the contrary, in addition to demulcent remedies, alkaline carbonates or ace- tate of potassium are the best remedies. The assertion, which has often been repeated, that benzoic acid taken internally renders alkaline urine more quickly and certainly acid than other acids, has not been confirmed by the results of numerous experiments performed by me with refer- ence to this point. III. THE APPEARANCE OP UNUSUAL (ABNORMAL) CONSTITUENTS IN THE URINE. All changes of the urine which come under this head have a great practical importance, for in all cases we must infer the existence of diseased conditions. Every abnormal constituent which appears in the urine has its own signification ; we shall, * Rechtfertigung der verstandesrecliten Erfahrungsheillelire, 2. Aufl., Bd. 3, S. 211, et seq. Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE URINE. 379 tterefore, immediately proceed to consider the various abnor- mal constituents. § 97. AlBUMEN. A. The detection of albumen in urine has already been described in § 23. But since it is not always very easy, and certain pre- cautions are required, and, moreover, physicians may very easily be led into error in testing for this substance by sometimes overlooking albumen when present, and sometimes wrongly considering it to be present when this is not the case, it ap- pears best to return to the subject once more. We detect albumen in the urine : 1. By adding nitric acid. When much albumen is present, an intense white turbidity is formed in it, or the fluid changes to a white pulp. In such cases no doubt can exist about the presence of albumen in the urine after this reaction. But the case is different when only a small quantity of albumen is present ; the slight cloudiness which occurs may then be over- looked, or a cloudiness produced by the presence of other mat- ters, such as urates, mucus, and the like, may be considered as due to albumen. It is best, therefore, to proceed with a cer- tain caution in adding nitric acid. As Heller has advised, a somewhat broad liquor glass is the best vessel to use in performing this test ; it is two-thirds filled with urine, and a little nitric acid is allowed to flow down the side of the glass slowly and carefully, so that it may collect at the bottom. If albumen is present, a turbid zone sharply de- fined on the upper and lower surface is formed above the acid, which is not readily overlooked on account of the contrast; this process, therefore, may serve to detect the slightest traces of albumen in the urine. A cloudiness of the urine, depending on the presence of urates, may be produced by the nitric acid, but this cloudiness, when the test is performed as above, is sharply defined only on the lower surface toward the layer of acid, while above it pervades almost the whole urine in the form of cloudy streaks. An experienced person is able by this procedure to distinguish between the zones of albumen and urates when they occur together. It is observed that imme- diately above the clear layer of acid there- is a cloudy zone of coagulated albumen sharply defined both on the upper and Digitized by Microsoft® 380 SEMIOLOGY OF HUMAN UBINE. lower surface ; above this there is a zone of clear urine, and then a layer which is made cloudy by urates.* (Compare also § 23, page 95, et seq.) 2. By hoiling the urine, so that the albumen is coagulated, and, when much albumen is present, a flocculent coagulation is the result ; when little is present there is a cloudiness only. But this test may deceive us also ; a cloudiness of the urine may result from boiling when no albumen is present. This cloudiness in the majority of cases is caused by the earthy phosphates ; in very rare cases (in osteomalacia) it depends on the presence of a peculiar protein substance different from albumen.t Both these last-named turbidities are very readily distinguishable from that due to the albumen, since they dis- appear again after the addition of a little acid (acetic or hydro- chloric acid), which is not the case with the cloudiness due to albumen. These two turbidities may, furthermore, be dis- tinguished from each other by the fact that the protein sub- stance is dissolved by caustic potash, but the earthy phos- phates are not. The protein substance is also distinguished from albumen by the fact that it is not precipitated by nitric acid. Albumen in urine, moreover, is not under all circumstances coagulated by boiling ; for instance, not when the urine is al- kaline. We must, therefore, always test the reaction of the urine before boiling, and, if it is alkaline, we must carefully neutralize it with acetic or nitric acid. Sometimes, though very rarely, albumen is not precipitated even in an acid urine by boiling. This is the case when the urine contains a large quantity of free hydrochloric or nitric acid, each of which may form a compound with albumen which is soluble in both cold and boiling water. (Bence Jones.) "When the physician wishes to decide the question with cer- tainty, whether a specimen of urine contains albumen or not, it is best to try both the nitric acid and the heat tests. These reactions, however, only allow of the detection of that form of albumen which occurs most frequently in the urine, and which especially forms so-called albuminuria (serum albu- men). Besides this, still other varieties of albumen may occur * Heller's ArcMv fur Ctomio und Microsc, 1852, p. 163, et seq. f Heller in his Arohiv, 1852, p. 167. Digitized by Microsoft® VNU8UAL CONSTITUENTS IN TEE URINE. 381 in the urine, all of whicli are not indicated by these reactions, but require special chemical tests for their detection and separa- tion. For particulars on this point see below (11.). B. What significance has the presence of albumen in the urine for the physician ? The answer to this question, which has occupied pathologists and physicians, is very difficult, and if we do not proceed very carefully, we run the risk of drawing false conclusions when the urine contains albumen, as has very frequently happened to physicians, many of whom are inclined to regard every albu- minuria as indicative of a dangerous organic disease of the kid- ney (morbus Brightii in its broadest sense). The following points will assist us in considering the diagnosis and prognosis : 1. The albumen in the urine may depend on an organic dis- ease of the parenchyma of the kidney, which is combined with its serious change and disorganization (exudation into the renal tubuli, alteration and separation of the epithelium — Bright's disease in the broadest sense ; amyloid degeneration of the re- nal capillaries, etc.). This supposition becomes almost a cer- tainty when casts are found in the urine at the same time, less of a certainty when only separated epithelial cells from the urinary tubules are found. (Compare § 116.) It is rendered probable by the simultaneous presence of dropsy, or when a a large amount of albumen has been present in the urine for a long time, weeks or months. The prognosis in such a case is usually unfavorable. Still, a few apparently tery bad cases running an acute course may completely recover, and chronic cases may last very long (for years) without seriously endanger- ing the health or life. 2. The albumen in the urine may depend on a local disease of the uropoetic system when Bright's disease does not exist. When blood, blood plasma, or pus is mixed with the urine it contains albumen. In this case, however, the urine also con- tains, besides albumen, blood corpuscles, blood coloring matter, fluid or coagulated fibrine, and pus corpuscles. The diagnosis of these foreign constituents and their signification may be found in the following sections. In rare cases the urine may also contain albumen from an abundant mixture with the spermatic fluid.* * Bence Jones, Animal Chemistry, 1850, p. 108. Digitized by Microsoft® 382 BEMIOLOGT OF HUMAN UBINK But the urine may also contain albumen without this admix- ture from an irritation and hyperemia of the kidneys, namely, passive hypersemia, in which the capillaries of the kidney ap- pear to be so modified that they allow a little albumen to filter through their walls into the urine. This is sometimes observed after the use of powerful diuretics, cantharides, etc., after liga- ture of the renal veins or of the aorta below the origin of the renal arteries, after the injection of a large quantity of water into the blood, and especially under conditions which increase the blood pressure in the renal vessels. Many diseases, with- out doubt, may have a similar action on the kidneys, and there- by render the urine albuminous. 3. But probably albumen may pass into the urine also on account of certain alterations in metamorphosis and especially in the blood, without local disease of the kidneys. But we know very little as yet of these relations and their mode of action ; however, the following points may be laid down with more or less probability : a. In that condition of the blood in which the serum be- comes poor in albumen and rich in water (hypalbuminose, hydrsemia) we sometimes see albumen appear in the urine. b. When albumen in solution is injected into the blood of animals, or when they are largely fed with albumen, we some- times find the urine albuminous, sometimes not. A further pursuit of these experiments by Corvisart, Schiff, Stockvis, Parkes, Pavy, and others has led to the opinion that certain forms of albumen pass through the walls of the renal vessels more readily than others, and it has been supposed, further, that certain modifications of the blood albumen, which are formed in disease by abnormal metamorphosis, may give rise to albuminous urine. The experiments of Pavy* indicate this. They show that the albumen contained in the urine does not always act in the same way on dialysis, and, moreover, it has different qualities from the albumen of the blood serum. Terrell + declares that in temporary albuminuria and in the beginning of Bright's dis- ease the albumen in the urine possesses different characteristics * Lancet, May, 1868. t Qaz. des HSpit., 1863, 63. Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE UBINE. 383 from that in an adyanced case of Briglit's disease. In the first case, from the presence of paralbumen a precipitate produced by strong alcohol is dissolved again by a large amount of water, and potassio-cupric tartrate causes, especially when heated, a beautiful violet color. In a marked case of Bright's disease, on the contrary, the alcoholic precipitate is not dissolved again by water and the copper solution produces no violet color. Others (Gerhardt, Masing, Schultzen and Eiess, Edlefsen) have found varieties of albumen in the urine of patients which differed from ordinary serum albumen: paralbumen, paraglo- bulin, peptone, etc. (Compare below, page 384, et seq). A. Creitte * has also communicated experiments on the action of serum albumen when injected into the blood. He found that, as a rule, an albuminuria was produced by it which was only transitory, but sometimes was accompanied by very bad results. Whether in the cases of the separation of albumen considered under a and b, a visible alteration in the kidneys (hypersemia and dilatation of the vessels, partial separation of the epithe- lium of the urinary tubules) precedes or not, cannot usually be determined. But this much is certaii;, that this affection of the kidney when it exists is only temporary ; and consequently from the presence of albuminuria alone we cannot conclude that there is material alteration of the kidneys (so-called Bright's disease), but only when at the same time there are other signs, such as the presence of renal casts in the urine. It is self-evi- dent, moreover, that we should only think of Bright's disease in those cases in which the urine has been constantly and for some length of time albuminous. If we have reason to believe that Bright's disease does not exist, it remains to determine whether the albuminuria is de- pendent on an inflammation of the kidneys or on a change in the blood. The answer to this question naturally requires a further examination of the case, and is sometimes positive, but often only conjectural. It is usually of great value in reference to the prognosis and treatment, especially when it is a question whether we shall use diuretics or not. The following suggestions may serve as hints in forming an opinion concerning many cases of albuminuria : * Henle und Pfeuffer's Zeitsehr. 36, p. 90, et seq. Digitized by Microsoft® 384 SEMIOLOaT OF HUMAN UBINE. Waldenstrom repeatedly observed the occurrence of albumen in tbe urine after the external or internal use of carbolic acid. Hegar and Kaltenbach * frequently, but not always, found the urine to be albuminous after the administration of chloroform. E. Gerhardtt repeatedly observed that patients who fre- quently or constantly had a temperature of over 40° C. had albu- men in their urine, if not in the ordinary form, at least in a form described by him as latent, which is not precipitated by boiling or on the addition of nitric acid, but is precipitated by alcohol (peptone). H. Senator | showed that several different albuminoid bodies occur in the urine, yet in different amounts under different con- ditions and in varying proportions to each other. Indeed albu- minoid bodies occur in the urine which were not previously found in the blood, and, conversely, some are absent from the urine which are found in the blood. The albuminoid bodies of which we speak are : 1. Globulin or pare/globulin ; it is detected by diluting the albu- binous urine with water until its sp. gr. is 1*002 or 1"003, and conducting carbonic acid gas into it for two or four hours. The cloudiness which is thus produced forms usually, but not always, after one or two days, a milky precipitate, which dissolves again on adding very dilute hydrochloric acid or a solution of chloride of sodium and concentrated acetic acid. Cases of amyloid de- generation of the kidney showed the greatest amount of para- globulin, and cases of acute nephritis contained a large amount of it. On the other hand, very little or no paraglobulin was found in chronic diffuse nephritis. In catarrh of the bladder the urine always contained paraglobulin, besides a relatively scanty amount of albumen. 2. Alkali albuminate, that is, a body which is obtained from blood serum after precipitating the paraglobulin with acetic acid, either does not appear in the urine at all, or only in very slight traces. 3. Peptone (precipitable with alcohol after separating the other varieties of albumen by boiling) is contained in small ■•' Virchow's ArcHv, 49, p. 437, et seq. f Deutsches ArcMv f. klin. Med., 1868, v., p. 213, et seq. jiUeber die im Harne vorkommenden EiweisskSrper, etc., in Virchow's AtcMv, 1874, Band 60, p. 476, et seq. Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE URINE. 385 amount in every albuminous urine, and, according to Gerhardt (see above), under certain circumstances occurs in uriue wMch contains no albumen coagulable by heat. Sometimes a quantitative estimation of tlie albumen separated by the urine is desirable, especially in cases where we wish to know how much is thus removed from the body, and whether an essential impoverishment of the blood is to be feared from this cause or not. (Hypalbuminosis, hydrsemia). In order to make such quantitative estimations of the albu- men practically serviceable to the physician, we mention the following considerations, and we must not only determine the percentage of albumen in the urine, but must also calculate it for a given time, preferably twenty-four hours. The quantity of albumen which is passed with the urine in albuminuria varies greatly from a minimum (less than one grm. daily) to 20 and even 30 grm. of dry albumen in twenty-four hours. Keeping these facts in mind, the loss of albumen with the uriae may be considered in the following categories : It is insignificant and has hardly any influence on the compo- sition of the blood and metamorphosis, when the amount sepa- rated is less than 2 grm. in twenty-four hours. The loss is moderate when the daily quantity averages 6 or 8 grm. The loss is considerable when it exceeds 10 or 12 grm. 20 grm. and more of albumen in twenty-four hours is an un- usually large quantity and belongs among the exceptions ; it rarely lasts long at this height. 28 '3 grm. of albumen was the maximum quantity which I have thus far seen pass off with the urine in twenty-four hours in a large number of observations. If we seek to obtain an approximate idea as to the action of such a loss of albumen on the quality of the blood, and espe- cially whether it can bring about a morbid diminution of the albumen in the blood serum (hypalbuminosis, hydrsemia), we must proceed as follows : We will assume the most unfavorable conditions, in which the serum constitutes only about one-half of the whole amount of blood, and according to which an adult possesses about 6,000 grm. of blood serum containing 8 per cent., in all only about 480 grm. of albumen. Moreover, if we sup- pose that as long as the albuminuria lasts, no albumen is formed from the protein bodies which are taken as food, and also, as 25 Digitized by Microsoft® 386 BBMIOLOar OF nUMAN UBINB. is scarcely probable, none from the hsematoglobulin of the broken-up blood corpuscles. If now 10 grm. of albumen are passed daily on an average, in ten days 100 grm., the amount of albumen of the blood serum sinks to 380 grm., and the relative amount in the blood serum is diminished from 80 to 64 parts in a thousand, which corresponds to a tolerable de- gree of hydrsemia. After twenty-six days such an albuminu- ria would have diminished the amount in the blood serum to 37 parts in the thousand — a number which nearly corresponds with the minimum amount of albumen in the blood serum in hydrsemia observed by Becquerel and Eodier. These consid- erations show how, under the above conditions, a high degree of hydrsemia may be produced in a relatively short time by an abundant albuminuria. Experience teaches us, however, that the action of an albuminuria on the quality of the blood is only rarely so considerable, except in a few very acute cases accompanied by fever, and in patients whose appetite and di- gestion are lost. When we remember that 100 parts of meat ■contain about 15 or 20 parts of protein .substances, which, if the digestion is good, are almost wholly converted into a solu- ble form of albumen, and pass into the blood, under favorable circumstances a loss of 10 grm. of albumen daily may be re- placed by the additional ingestion of about three ounces of meat or a corresponding quantity of other food containing protein ; and, in fact, I have often seen in patients with a fair digestion and without fever, who were well nourished, a moderate degree of albuminuria last for months or even years without causing a perceptible hydrsemia or symptoms which pointed toward it. The methods which are used to determine the albumen in the urine quantitatively were described in § 75. A. Stscherlakoff and Chomjakoff * have undertaken compara- tive examinations as to the accuracy of these different methods. According to these authors the estimation of albumen by coagu- lation and weighing (compare page 293, et seq.) does not give perfectly accurate results, because all of the albumen is not pre- cipitated by it. "When the urine contains 0'5 per cent, of albu- men, from four to eight times as much albumen remains dis- solved as is precipitated. When it contains 1 per cent., that * Deutsches Arohiv f. klin. Med., 1870, viii., p. 318, et seq. Digitized by Microsoft® UNU8UAL CONSTITUENTS IN THE URINE. 387 whicli remains dissolved nearly equals that whicli is precipi- tated. When there is more than 2 per cent, of albumen, about one-third of it remains in solution. The estimation of albumen from the difference of the sp. gr. before and after coagulation of the albumen by the method of Lang and others (compare page 297, 3) gives very inaccu- rate results. On the other hand, the optical determination of the albumen by the polariscope (compare page 296, B) is the most accurate, and at the same time the simplest and quickest method. P. Liborius * has also undertaken comparative experiments as to the accuracy of the different methods of determining albu- men. According to him its precipitation by alcohol, by which peptone is also obtained, gives the most accurate results known at present. For mere approximate determinations of the amount of albu- men in the urine, when the physician only wishes to know whether the separation of albumen in albuminuria is inconsid- erable or large, and especially whether it increases or dimin- ishes, the following procedure, which does not require extensive apparatus, may be adopted : Test tubes of the same diameter are to be chosen in precipi- tating the albumen from the urine by boiling or adding nitric acid, and the precipitate of albumen is allowed to remain at rest for twelve or fourteen hoars. The relative amount in compari- son with the quantity of urine used in the experiment may thus be easily approximately estimated. If the tests of the urine of different days are preserved, their amounts of albumen may be compared, and we may easily see whether it increases or not. This estimation is more exact, when we use, instead of test tubes which are rounded at the bottom, not too narrow glass tubes with a diameter of from \ to J of an inch and an even bore, which are closed below by a tightly fitting cork cut off squarely, and into which the boiled urine is poured. If the albumen precipitate has completely settled in these after twelve or twenty-four hours, we can estimate with the aid of a measure held near the tube how many tenths or hundredths of the whole *Beitrage zur quantit. Biweissbestimmung im Deutsch. Archiv f. klin. Med X., 1873, p. 319, et seq. Digitized by Microsoft® 388 SEMIOLOGT OF HUMAN URINE. quantity of urine tlie precipitate of albumen occupies. But we must not forget that only tlie relative and not the absolute quanti- ty of albumen contained in the urine is learned in this way. Apart from this also such calculations always remain somewhat uncertain ; for according as the albumen coagulates on boiling in coarser or finer particles, and according to the specific gravity of the urine which remains behind, the precipitated albumen sometimes assumes a larger and sometimes a smaller Tolume, and experiments, in which the albumen has been determined at the same time by weight and by volume, have shown me that in estimating it according to the latter method errors of 30 and even 50 per cent, may be made. Therefore the statements of some of the French pathologists with reference to the separa- tion of albumen in ialbuminuria under the influence of various agencies, as far as they are founded on the estimation of the albumen by volume, must be received with great caution. § 98. rrBROTE. Fibrine under various circumstances may appear in the urine sometimes coagulated and sometimes in solution. Coagulated fibrine appears either in large particles visible to the naked eye, as blood coagula, which cannot be mistaken (see the following section), or, more rarely, in the form of colorless, sometimes solid, sometimes gelatinous fibrinous coagula; or again in very small particles visible only with the microscope in the form of so-called urinary casts or cylinders. (See Urinary Sediments, § 116.) Dissolved fibrine in the urine forms the so-called coagulable urine, which is characterized by the formation of fibrinous coagula in it after some time (generally several hours after it has been passed); sometimes these only cover the bottom of the vessel and form a sort of coherent sediment in the lower part of the urine; sometimes it occupies the whole mass of urine and transforms it into a completely gelatinous mass. This coagulable urine is seen in this country very rarely, but outside of Europe it is met with more frequently (Brazil, Isle de France, etc.). The fibro-gelatinous mass which forms may very readily be confounded with that which occiys much more frequently with Digitized by Microsoft® UNUSUAL CONSTITUENTS IN TEE UBINE. 389 us, and which is formed by the action of carbonate of ammo- nium upon the pus corpuscles contained in the urine, as often happens in catarrh of the bladder. (Compare § 113 and § 114.) Coagulable urine sometimes contains blood also. In such cases we cannot be sure that the urine contains fibrine as well as blood, unless the fibrinous coagulum is so large that it can- not be ascribed to the presence of the blood alone. I saw such a case in a woman who was suffering from Bright's disease. Here, for a long time, a very pale-red fibrinous coagu- lum containing numerous pus corpuscles and a few blood cor- puscles was regularly formed at the bottom of the glass some hours after the urine was passed. The blood corpuscles, how- ever, were far too few to indicate that the blood which they represented could have yielded the whole of the fibrinous co- agulum. Importance., Fibrine in the urine, whether dissolved or co- agulated, always indicates that at some part of the uropoetic system an exudation of a fibrinous fluid (blood plasma) has oc- curred. In most cases this fibrine comes from the kidneys, but it may arise from some other part of the urinary passages. § 99. Blood in the Ueine. (Blood Corpuscles. Blood Coagula.) A. Detection. The urine has the color of blood, and under the microscope shows the characteristic blood corpuscles. (See § 51.) If the quantity of blood is very small, we cannot be sure of finding the blood corpuscles, unless the urine has stood a long time. They then become deposited as a red sediment on the bottom. In this way we may recognize even a very small amount of blood with the unaided eye : should any doubt exist as to the nature of the sediment, it must be cleared up by a microscopic examination. The blood may coagulate, if the quantity is rather large, either within the urinary tract, when the large blood coagula may stop up the urinary passages, causing dysuria, strangury, or retention of the urine, sometimes giving rise to the formation of urinary calculi even, or the coagulation of the blood may take place in the urine after it has been passed. (Compare § 98.) Digitized by Microsoft® 390 BEMIOLOGY OF HUMAN UBINE. B. Importance. Blood corpuscles or blood coagula in the urine always indicate that a haemorrhage has occurred some- where in the urinary passages. The causes of such a hsemor- rhage and its results are very various, and this is not the place to describe at length all of the possible causes which may give rise to it. The following considerations will serve as guides in the examination : When the urine contains very much blood, it usually comes from the pelvis of the kidney, the ureters, or the bladder, rarely from the kidneys themselves. Sometimes the cause of the haemorrhage depends on a general scorbutic condition, the diagnosis of which presents no difficulties to the careful physi- cian. With this exception haemorrhages from the pelvis of the kidney and the ureters is most frequently caused by renal calculi, more rarely by ulceration of these parts from other causes. In such cases, in addition to the haemorrhage there usually exists an inflammation of the pelvis of the kidney and of the ureters (pyelitis) ; the urine contains, in addition to the blood, pus corpuscles also, sometimes fragments of calculi or gravel ; there is pain in the region of the kidneys and in the course of the ureters. This set of symptoms usually establishes the diagnosis. If pain is wanting in the region of the kidneys or in the course of the ureters, the source of the haemorrhage is proba- bly to be found in the bladder. The causes may be : hyperae- mia (so-called vesical haemorrhoids), vesical calculi, erosions, and ulcerations of the mucous membrane of the bladder, or serious organic lesions of the bladder, especially cancer, which has become softened. The other symptoms of disease of the bladder which are present in addition to the bloody urine in such cases, generally enable us to readily discover the source of the haemorrhage, and a careful examination and continued observation, as a rule, will give us a clue to the nature of the disease. Sudden or temporary symptoms of disease of the bladder (dysuria, ischuria) occurring without premonitory symptoms may arise when the haemorrhage has taken place, not in the bladder, but in the pelvis of the kidneys or in the ureters. This happens when the blood which has found its way to the Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE UBINE. 391 bladder coagulates there, and tlius occludes the urethral ori- fice, or when blood coagula are washed out of the ureters into the bladder and in the same way render micturition difficult or impossible. If the quantity of blood in the urine is small, and there are symptoms present which indicate disease of the urinary pas- sages, it is probable that the blood has come from the paren- chyma of the kidneys, and especially from the vessels of the Malpighian corpuscles, and we have to deal with a disease which belongs under the large class of so-called Bright's dis- ease. In such cases when the haemorrhage is not very transi- tory, the urine usually contains besides blood, fibrinous casts, or pus corpuscles and granule cells, whose presence not only strengthens the diagnosis, but also sometimes enables us to diagnosticate with more or less probability a certain form of kidney disease. In all cases of haemorrhage in the uropojtic system the physi- cian must not be contented with simply diagnosticating the seat and cause of it, but must also try to determine the possible consequences for the purposes of prognosis. The following considerations may be of service in this re- spect : A haemorrhage from the urinary passages is only rarely so considerable that it directly causes an essential diminution of the blood corpuscles in the body, and thereby brings about anaemia or oligocythsemia. More frequently the evil consequences arise as follows : The effused blood coagulates wholly or partially in the urinary passages and occludes the ureters or urethra, and thus hinders the evacuation of urine, or these coagula may give rise to the formation of permanent concretions (urinary calculi) in the urinary passages. Even in those cases in which the quantity of effused blood is very slight, small coagula may become the nuclei of future urinary calculi. In forming the prognosis of a haemorrhage, in addition to these possible results we must always take into account the re- sults of the process which gave rise to the haemorrhage : the affection of the kidney, the pyelitis, the disease of the bladder, etc. Every specimen of urine which contains blood corpuscles Digitized by Microsoft® 392 SEMIOLOGY OF HUMAN URINE. must also contain fibrine and albumen, because these substances form integral constituents of tbe blood. Only a careful inves- tigation based on approximate quantitative determinations of these three constituents of the blood can decide -whether the whole quantity present in the urine is derived from the blood which has been effused, or whether in addition to the blood there has been an exudation of fibrine or of albumen. (Compare §98.) § 100. Dissolved Blood. Dissolved H^matoglobulin. (Haemoglobin and Methsemoglobin.) Sometimes the urine has a bloody color or is reddish brown, brownish black or even inky black, and yet no blood corpuscles can be detected in it by the most careful microscopic examina- tion. If, however, such urine be boiled either alone or after the careful addition of a little acetic acid, a more or less abun- dant brownish-red coagulum forms in it, which is precisely similar to that which blood diluted with water gives on being boiled. If this coagulum is then boiled with alcohol which contains sulphuric acid, the fluid becomes colored reddish brown by dissolving haemoglobin. We can thus, especially when the spectral analysis is employed, prove with certainty the presence of dissolved blood pigment in the urine, and at the same time discover whether it consists of original haemo- globin, of altered haemoglobin (methaemoglobin), or of haematin. (See § 51.) Such urine is occasionally met with in diseases which are associated with what is called a dissolved state of the blood, as in scurvy, in putrid and typhus fevers, in malignant remit- tent fever, and after the inhalation of arseniuretted hydrogen gas.* Examples. A., a young man, suffering from a severe attack of typhoid fever, passed at the height of the disease, for several consecutive days, urine of a blood-red color, which under the microscope showed no traces of blood corpuscles, but on boil- ing gave an abundant coagulum of haemoglobin. After a few * J. Vogel im AicMv d. Vereins f . gemeinsch.. Arbeiten., Band 1, Heft 3, p. 309. Digitized by Microsoft® UNUSUAL CONSTITUENTS IN TEE URINE. 393 days this state of the urine disappeared, and the patient re- covered slowly though perfectly. X., in perfect health, while performing an experiment, inhaled a gaseous mixture, which besides atmospheric air contained hydrogen mixed with some arseniuretted hydrogen. He be- came momentarily ill, but soon recovered. The urine which he passed a short time afterward was inky black ; it contained no blood corpuscles, but on boiling yielded an abundant coagulum of hsBmoglobin. This condition of the urine lasted about twenty- four hours. Also, some smelters, who inhaled arseniuretted hydrogen in the extraction of silver from the ore and suffered from poison- ing in consequence, three of the nine cases affected proving fatal, passed bloody urine.* A dog which was allowed to inhale a large quantity of arseni- uretted hydrogen experimentally, also passed a urine of a dark blackish-brown color containing a large amount of haemoglobin. Recently, since the operation of transfusion has been per- formed repeatedly, a number of the patients operated upon have also passed dissolved blood-coloring matter with the urine.t The passage of haemoglobin with the urine in such cases may perhaps be explained in the following way : The blood corpuscles are being constantly decomposed in the body by the metamorphosis of tissue, and haemoglobin is thereby set free. When the metamorphosis takes place normally, it is probable that this haemoglobin which is set free, always only in very small quantity, is further decomposed : the globulin is finally removed from the body in the form of urea and uric acid ; the haematin also undergoes further change, and is probably sepa- rated fron the body finally as urinary and biliary coloring mat- ter, so that in the normal course of metamorphosis, haemoglo- bin never appears in the urine. When, however, in patholo- gical processes very large quantities of blood corpuscles are at once decomposed, the amount of haemoglobin present in the i * Trost in Eulenberg's Vierteljahrsschr. f. gerichtliche Medicin u. fiffentl. Sanitatsweaen, Band 16, p. 269, et seq. f Oehme, Sitzungsberlcht d. Dresdner Gesellscli. f. Natur. dun Heilkunde v. 11. April, 1874. See also Landois, Centralbl. f. d. medic. Wissensch., 1873, No. 56 and 57. Digitized by Microsoft® 394 SEMIOLOGY OF HUMAN URINE. blood is so great that tlie whole of it cannot undergo the nor- mal change, and a part of it then apparently passes unchanged into the urine, just as happens with other matters which do not usually appear in the urine, as, for example, sugar, biliary sub- stances, and perhaps also albumen when present in the blood in excess. This is apparently confirmed by the experiments of Ponfick,* which showed that small quantities of haemoglobin introduced into the vascular system of animals are decomposed by meta- morphosis and disappear, while large quantities give rise to hsemoglobinuria and are in part separated unchanged by the kidneys. Importance. The presence of haemoglobin in the urine is important to the physician in two ways. 1. It indicates that there has been an excessive pathological decomposition of blood corpuscles. Under this head there are two sorts of eases which we must distinguish in practice : a. The cause of the decomposition of the blood may be a temjwrary one, in which case the evil results aro confined to the loss of a greater or less quantity of blood corpuscles ; the prog- nosis is favorable, as in the examples given above. b. The cause of the decomposition of the blood may operate perma icntly ; a peculiar dissolution of the blood is thereby brought about which endangers life. The prognosis is unfavor- able or at all events doubtful. It is seen in cases of severe scurvy, in typhus with dissolution of the blood, in septic fevers, etc. 2. We know from the observations of Meckel, Heschl, Fre- richs, and particularly from the beautiful experiments of Jul. Planer,t that in certain cases, and very probably in those cases in which a large amount of haemoglobin is set free, granular pigment collects in the blood and may produce serious results by obstructing the capillary blood vessels, especially in the brain (melanaemia). It, therefore, appears advisable to exam- ine the blood microscopically in such cases for any deposits of pigment which may occur before giving the prognosis. In such * Vircliow's Arcliiv, Band 63, p. S28, et seg. f Ueber das Vorkommeu von Pigment im Blute, Zeitsctr. der Wiener Aerzte, 1854, p. 137 and 380. See also : Oppolzer, Wiener med. Wochenschr., 1860, 25 and 36 ; Mettenheimer, Wiirzburger med. Zeitschr., 1863, p. 1, et seq. Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE UBINiJ. 395 cases of melansemia collections of pigment sometimes occur in the urine. (See § 116, p. 437.) § 101. Fat.* Our knowledge concerning the occurrence and signification of fat in the urine is still very incomplete. We do not know with certainty how often, in what quantity, and under what conditions it appears in normal urine : and the little which has hitherto been ascertained of its occurrence in pathological cases also appears unsatisfactory. The subject, therefore, requires further investigation ; however, what is already known indi- cates that the occurrence of fat in the urine promises to be of importance in the recognition and prognosis of many patholo- gical conditions, especially of fatty degeneration of the kidneys. A. Detection. To ascertain the presence of fat in the urine we resort to the process given in § 33. It is best to proceed as follows : 1. Sometimes we are able with the unaided eye to see fat drops in the urine similar to those which are seen floating on soup. These must be further tested by the very simple expe- dient of ascertaining whether the greasy spots which they make on paper remain after the paper has been dried. In all such cases, however, the physician must first assure himself that the fat in the urine is not accidental before he admits its existence — that it has not become mixed with the urine from unclean oily or fatty urine glasses, chamber vessels, medicine glasses, etc. This is a source of error which is far from uncommon. 2. In other cases the fat is recognized by the microscope. It appears in the form of drops or granules familiar to all mi- croscopic observers, either free or enclosed in cells, masses of exudation, fibrinous casts, etc. To find them we must either seek on the surface of the urine, where free fat drops usually fioat on account of their light specific gravity, or at the bottom of the urine when the fat is enclosed in cells or coagula which form sediments. *C. Mettenheimer, Archiv f. gemeinsch. Arbeiten, Band 1, Heft 3, p. 374 A. Q. Lanz, De Adipe in Urina, Dorpati, 1851. L. Beale, London Microso. Joum., January, 1853, 1, 3. Schmidt's Jahrbuch., 1873, 7, p. 7. Kletzinsky, in Heller's Archiv, 1853, p. 387. Digitized by Microsoft® 396 SEMIOLOGY OF HUMAN UBUSfE. 3. But the fat may be in such a minute state of division in the urine that it cannot be recognized even with the microscope. Then there is nothing left but to test the fat chemically as de- scribed in § 33, C, and § 82. B. Importwnce. As far as we can judge at present, fat ia the urine, when not of mere transitory occurrence, and when it lasts a considerable time, is of importance to the physician chiefly from the fact that its presence leads to the suspicion of a fatty degeneration of the kidneys, which may exist alone (fatty kid- ney) , or may be associated with contraction of the organ, as in one of the various forms of so-called Bright's disease. In the last case the formation of fat occurs either in the secreting cells of the kidney (epithelium of the urinary tubules), or it arises from the fatty metamorphosis of exudations deposited in the kidneys. It is not improbable, however, that fat in the urine may de- pend on other causes besides those mentioned here : Upon a fatty degeneration of the epithelial cells of the ure- ters and the bladder. Upon an excessive amount of fat in the blood, which might possibly occasion the passage of fat into the urine without a coexistent fatty degeneration of the parenchyma of the kidney. Thus Bernard sometimes, though not always, saw fat appear in the urine of dogs who were fed on a very fatty diet. ^ For a more accurate study of these relations it will usually be necessary to determine the amount of fat in the urine quan- titatively, either by an approximate estimation or, more accu- rately, by chemically extracting and weighing the fat which is passed in a given time — say twenty-four hours. Such a quan- titative determination of the fat should be carried out accord- ing to § 82, or better still by Kletzinsky's method. He first boils the evaporated urine with alcohol, to which a couple of drops of acetic, acid have been added, then evaporates to dryness again on the water bath and afterward extracts with ether. By this process the organic matter is better prepared for the subsequent removal of the fat by ether, and any saponi- fied fat which may be present is deprived of its alkaline base and incorporated with the ethereal extract. Such estimations of fat, however, are troublesome, and require much time for their performance. Thus far only a few such investigations Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE URINE. 397 have been made, and I know of none in wliicli the quantity of fat separated in a definite time, say twenty-four hours, has been reckoned. Therefore, we have, thus far, no means of comparison. The following experiments, in the meantime, may serve to aid us : Kletzinsky found in the urine of different persons who suf- fered from Bright's disease the following quantity of fat in 1,000 parts of urine : 0-24— 0-26— 0-28— 0-25— 0-37— 0-48— 1-27. Beale, on the other hand, found in one case 14 parts of fat in 1,000 parts of urine. So-called chylous urine (see page 142) contains more or less fat in suspension, which gives it a milky appearance, and in addition to albumen, it frequently contains fibrins, and lymph and blood corpuscles. Lewis declares that at times there is a peculiar entozoon present also. (See § 118.) The discharge of such urine — called, also, galacturia — is only rarely observed in Europe ; on the other hand, it is observed with tolerable fre- quency in some of the tropical countries (East and West Indies, Isle de France). It is not yet explained how this disease, which often lasts a long time, originates.* Recently I had an opportunity, through the kindness of Dr. W. Harnier in Wildungen, to observe a very interesting case of well-marked galacturia, which originated, not in the tropics, but in Germany. The patient, a young man, for two years and a half had passed, almost without exception, a perfectly opaque urine of white color, which exactly resembled in appearance milk which contains a good deal of fat. The turbidity deperids wholly on fat, which is, for the most part, very finely granular, and only has a few large fat drops like those in milk. The urine is cleared up by shaking with ether, and an abundant residue of semi-fluid fat remains behind after the ether is evapo- rated. The urine, moreover, contains a large amount of fibrine, which coagulates partly after the urine is_ passed, and partly while still within the urinary passages, and in the latter case the coagula are sometimes large and can only be passed through the urethra with a good deal of trouble. The urine contains only a trace of albumen. When the patient fasts, and at the * Concerning this subject see, besides a tolerably copious foreign literature, Ackermann, Deutsche Klinik, 1863, 23, et seq., and Eggel, Deutsches Archiv f. kUn. Med., vi., p. 434, 430. Digitized by Microsoft® 398 SEMIOLOar OF HUMAN URINE. same time drinks mucli water, the milky character of his urine temporarily disappears. § 102. BrLiABY Pigments. The bile pigments which occur in urine and the process re- quired to detect them have been studied in § 28. Importance. In rare cases traces of bile pigments have been found in the urine of persons in perfect health, particularly ia the hot season of the year.* Bile pigments are found in large quantities only in jaundice (icterus), and after phosphorus poisoning. Their presence may be thus explained : The natural passage of the bile from the liver into the intestine being, for any reason, impeded or arrested, they get into the blood by absorption. The biliary pigments having been accumulated in the blood are sepa- rated from it with all of the secretions, but most particularly with the urine. It is very doubtful whether a primary accumu- lation of bile pigments in the blood can occur, that is, whether they can pass directly into the urine from the blood without having previously formed a constituent of the bile. The idea originating with Frerichs, that the biliary pigment which is so abundant in icteric urine is derived partially from a decomposition of the biliary acids into biliary pigments in the blood, has not been confirmed. The presence of bile pigments in the urine has no great diag- nostic value, since we are usually able to recognize jaundice by other signs. In cases in which, owing to the slight yellow color of the skin, conjunctiva, etc., the diagnosis of jaundice is doubtful, the detection of the bile pigments in the urine may confirm it. Biliverdin and biliprasin generally prevail in the urine in jaundice. This indicates that the greater part of the bihary pigment in icterus undergoes a change during its absorption, or after it has reached the blood, or while it is passing into the urine. § 103. BiLiAKY Acids. The biliary acids which occasionally appear in the urine (choUc acid, glycocholic acid, choloidic acid, and their deriva- * Scherer, Ann. d. Chem. u. Ptarm., Band 57, p. 180-195. Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE UBINE. 399 tives, such as cholonic acid), may be detected by tbe metliods given in § 29 and § 83, and may be, at least approximately, de- termined quantitatively. Recently they have often been found in pathological urine, though always only in small quantity, especially in icterus and acute atrophy of the liver, by Kiihne,* Neukomm,t and Hoppe- Seyler.J Still their importance to the practitioner is slight, since it is rarely the case that important conclusions can be drawn from their presence or absence in reference to the diagnosis of a case of disease, or to assist in forming any other opinion con- cerning it. The presence of bUiary acids in the uriue is of prac- tical importance only by indicating an accumulation of these acids in the blood, which may be dangerous when it is consider- able, since they have a paralyzing influence on the nervous system, and more especially on the cardiac nerves. (Gerhardt.) In the meantime the following points may be mentioned in reference to this subject : Under normal conditions a considerable quantity of cholic acid is constantly being poured into the intestines with the bile. By far the greater part of it is absorbed again and passes back into the blood ; here the cholic acid is altered in a manner not fully understood, and disappears as such. If this change does not go on in the blood, so that the cholic acid accumulates there, then a portion of it may appear in the urine. As yet we do not know the conditions which prevent the disappearance of cholic acid in the blood, and favor its appearance in the urine. When we have learned these conditions better, we shall be able to determine fully the diagnostic and prognostic value of the presence of cholic acid in the urine. We may, however, de- duce a few conclusions from what is already known of these conditions as follows : It is not altogether inexplicable why we find, as a rule, only a little cholic acid in the urine in cases of icterus, where the urine is loaded with biliary coloring matters. When the flow of bile into the intestines is arrested, the bile pigment, whose normal avenue of exit from the body with the faeces is closed, must take an unusual course ; it is in part evacuated with the * Vircbow's Aicliiv, 1838, p. 310, et seq. t Arctiv f. Anat. und Phys., 1860, p. 364, et seq. % Vircbow's ArcUv, 1862, p. 1, et seq. Digitized by Microsoft® 400 SEMIOLOGY OF HUMAIf URINE. urine. The cholic acid, on the other hand, passes normally in great part back again into the blood and there disappears ; and since in icterus no change takes place in this respect, we can readily understand why, as a rule, in this disease we find much biliary pigment and little or no biliary acids in the urine. Moreover, as the disappearance of the biliary acids takes place in the blood and not in the liver, we should not, as a rule, expect to find them in diseases, of the liver, but in those diseases of the blood in which the normal decomposition of the biliary acids in the blood is impeded or arrested. We might ex- pect that these acids would be found only in the urine in those diseases of the liver which are accompanied by an increase of the biliary secretion, and as the result of which so large a quantity of biliary acids accumulates in the blood that their normal transformation is not completely accomplished.* § 104. SUGAE. To detect sugar in the urine we must proceed according to § 25, E. If the urine contains a large amount of sugar, its de- tection presents no difiiculty to one who is a little skilled. The dark brownish-red color which saccharine urine assumes when treated with potassic hydrate and heated to boiling for a time is sufficient proof. The further test with sodic or potassic hy- drate and cupric sulphate, as well as the tests with bismuth and indigo-carmine, will serve to confirm it. Sometimes the urine also contains alkapton (see § 26) and brenzcatechin (see § 39). These cases, which are probably rare, and whose etiology is still unexplained, have no clinical im- portance, but they may lead to a false conclusion that sugar is present when this is not the case, from the great resemblance of the reactions caused by their presence in the urine to those caused by sugar. It is only by the reduction of nitrate of bis- muth, the odor of caramel on boiling with potassic hydrate, and the fermentation test, that we can detect the presence of sugar in the urine when these substances are also present.t *For further particulars on this head, see Huppert (Archiv d. Heilk., 1864, p. 336, et seq.), and Ernst Bischofi (Henle u. PfeufEer's Zeitschr. f. rat. Med., 1864, p. 125, et seg.). ■\ Compare Dr. P. Fiirbringer, Berliner klinische Wochenschrift, 1875, No. 34. Digitized by Microsoft® VNU8UAL CONSTITUENTS IN THE UBINE. 401 In cases where tlie tests above mentioned give no decisive results, we may be sure that tbe urine in question contains no very considerable quantity of sugar, and this suffices almost always for the purposes of the physician. Occasionally, how- ever, we may wish to know whether in such a case the urine is perfectly free from sugar or not, and whether it contains a very small quantity, or a mere trace of it. To answer this question with certainty is difficult and requires time. We must then em- ploy all of the precautions which have been described on page 109, et seq. (preparation of an alcoholic extract of the evaporated urine, of a saccharate of potassium, etc.). To obtain an aceurative quantitative analysis of the sugar in a specimen of urine, we must proceed according to § 70. The methods of analysis described there, however, are rather com- plicated, with the exception of the optical method, and cannot, therefore, be easily employed by the physician, but, as a rule, must be entrusted to the chemist. In order to learn accurately the progress of the secretion of sugar, we must ascertain the quantity of sugar formed in a given time {x grms. of sugar in an hour, for example, etc.). Comparative trials of the accuracy of the different methods employed to determine quantitatively the sugar in the urine (the oxide of copper test, fermentation test, and that by means of the polariscope) have been made by Wicke and Listing.* Attempts have also been made to determine the quantity of sugar in diabetic urine from the specific gravity, and for this purpose tables have been drawn up which are said to show how much sugar urine of a certain specific gravity contains. This method is quite extensively used in England, but is very inaccu- rate and cannot be employed even for approximate determina- tions, as Bence Jones t has shown. On the other hand, W. Manassein X found that Eoberts' method of determining the quantity of sugar from the difference in the specific gravity of the urine before and after fermentation gave quite serviceable results. (Compare page 277.) Since the methods of determining the quantity of sugar in a specimen of urine as described above are difficult and tedious, * Henle u. Pfeufier's Zeitschr. , Neue Folge, Bd. 6, Heft 3. f Med. Times and Gazette, Feb. 4, 1854. :f Deutsches Archiv f. klin. Med., 1873, x., p. 73. 26 Digitized by Microsoft® 402 SEMIOLOOT OF HUMAN UBINE. I have frequently employed another process instead, which is quite sufficient for the purposes of the physician, who, as a rule, only wishes to know ahout how much sugar a diabetic urine con- tains, and more especially whether the quantity has increased or diminished. This process is founded on the fact that saccha- rine urine when boiled with potassic hydrate assumes a yellow- ish-brown color, and that from the intensity of this color the quantity of the sugar may be determined by the aid of a color scale in the same way that the coloring matter of the urine is determined. The best way is to proceed as follows : A weighed amount (about 2 grm.) of well-dried grape sugar is dissolved in 40 or 50 cc. of water, about double its volume of a tolerably concen- trated solution of potassic hydrate is added, and the mixture boiled 10 or 15 minutes. After cooling, the fluid, which has become dark brown, is treated with water until 1 cc. of it corre- sponds to 10 mgrm. of sugar. From this original fluid a scale of colors is prepared. For not very exact investigations a scale of a few members is sufficient, and we may use ordinary test tubes of as nearly as possible equal diameter. We fill the first one with a fluid consisting of one part of the original fluid and nine parts of water, so that 10 mgrm. of sugar are contained in 10 cc. of the fluid. The second tube is half filled with the fluid first used and then an equal quantity of water is added ; we then obtain a member of the scale in which 5 mgrm. of sugar are contained in 10 cc. A third, fourth, and fifth test tube are filled with fluids, 10 cc. of which correspond to 3, 2, and 1 mgrm. of sugar respectively, etc. If we prepare a scale of 10 or 12, members, and select large glasses of as nearly equal dia- meter as possible and having a capacity of ^ to 1 lb., we can arrive at a very accurate determination. When we have pre- pared such a scale, a measured quantity of the urine to be tested is boiled (when the urine is very saccharine 5 cc, when it contains but a little sugar 10 cc.) with double its volume of a solution of potassic hydrate ; after cooling it is placed in a glass vessel corresponding in form and size to those of the scale, and water is added to it until its color corresponds to that of one of the members of the scale. We may now from the known quan- tity of the sugar contained in that member of the scale very readily reckon the quantity of sugar in the urine. This method Digitized by Microsoft® UNUSUAL CONSTITUENTS IN THE URINE. 403 is very conTenient (it requires only a few minutes to perform it), and is, therefore, especially adapted for clinical purposes. Tke scale itself does not keep long, it is true, but the original fluid when preserved in a cool, dark place may be kept a long time, and a new scale may be quickly prepared from it. In the rare cases in which the urine contains large quantities of alkapton or brenzcatechin (see page 400), this method is naturally not applicable, since these substances also color the urine brown when treated with potassic hydrate. Importance. It is still very difficult at present to explain the cause of the occurrence of sugar in the urine. It, therefore, appears advisable to keep in mind the facts which are of most importance to the practitioner. From the standpoint of the physician two points are to be discriminated : 1. In the one case the urine not only contains sugar in large quantities, but it is for a long time constantly present (only when fasting do such persons sometimes pass a urine which is free from sugar.) 2. In the other case the urine contains only traces of sugar, or the sugar is present merely temporarily, or for a short time, or contains a considerable amount intermittently with intervals when it is absent. In the Jirst case we may conclude that the disease known as diabetes mellitus, glycosuria, is present. There are then usually other symptoms present which serve to assist us in making the diagnosis and prognosis : a very large quantity of urine of high specific gravity, great thirst, emaciation, dryness of the skin, etc. This is not the place to enter into a detailed description of the nature, cause, progress, and complications of diabetes mellitus, and I may remark here, that in all such cases the physician is justified in making, if not an unfavorable, at least a very doubtful prognosis. The prognosis is frequently more favorable in those cases in which the evacuation of a saccharine urine has bden observed after injuries of the brain, similar to those which are caused by the so-called sugar-puncture in animals, provided, naturally, that the injury to the brain does not of itself demand a bad prognosis. The second case, in which the urine contains only traces of Digitized by Microsoft® 404 SEMIOLOGY OF HUMAN URINE. sugar, or, only occasionally, large amounts of it, is observed in the course of several different diseases, and even in per- fectly healthy persons. The cause of it has hitherto been at- tributed to various conditions by different physiologists : to an immoderate use of saccharine and amylaceous substances, to disturbances of the functions of the brain and nervous sys- tem, especially of the medulla oblongata, to diminution of the respiration and absorption of oxygen, to excessive production of sugar by the liver, and to a diminution of the alkalies in the blood. It is always advisable for the physician in such a case to direct his attention to these etiological conditions and to as- certain whether any one of them is present, and to govern his therapeutics accordingly. But a perfectly satisfactory explana- tion and treatment of such a case will only be possible in the future, when the causes mentioned, which are still partly under discussion, shall be more accurately determined and their in- fluence on the elimination of sugar with the urine shall be more perfectly known than is the case at present. In the meantime the following seems to be the most probable view : When from any cause a greater quantity of sugar accumulates in the blood than can be decomposed in it by the process of metamorphosis — whether it be that an unusual quantity of sugar gains access to the blood, or that its decomposition in the blood is hindered in any way — a part of the excess may be passed off with the urine, just as is the case with many other substances. Under this head belongs the presence of small quantities of sugar in the blood of the arteries, veins,, portal vein, in the urine of pregnant, lying-in, and nursing women, and also in the urine of perfectly healthy men. After much controversy in this matter it now appears tolerably certain from the investi- gations of Briicke and Iwanoff, and contrary to the assertion of Seegen (see page 101), that the urine of healthy persons even sometimes contains small quantities of sugar. Such investiga- tions, however, have little value for the practitioner from a diagnostic p6int of view ; they rather concern the chemist and physiologist. It is still very difficult to obtain reliable results in this matter, since in investigations of this sort only the most exact methods of procedure and the purest reagents will enable us to exclude errors. Then, too, no one should experiment in this direction without a perfect mastery of the literature of the Digitized by Microsoft® UNV8UAL CONSTITUENTS IN THE UBINE. 405 subject, wMcli has already become quite extensive. Tlie two comprelieiisive treatises of Lehmann,* and the dissertation of Nicol. Iwanoff,t which contains the latest literature of the sub- ject, wiU best serve to give a general idea of the matter. According to De Sinety:}; sugar occurs in the urine of pregnant women and in lying-in women only when the lacteal glands are imperfectly emptied, when it regularly occurs. Conse- quently sugar is always found in the urine on the second or third day after delivery at the time of the milk fever. The secretion of milk at this time is quite abundant, while the child gets but little of it. The urine may be rendered saccharine at will in nursing dogs and rabbits by removing the young. The increase of sugar ia the blood could be detected when the milk was not removed. Sugar has sometimes been observed in the urine after having taken oil of turpentine (see page 102), also temporarily in teta- nus rheumaticus§ and in persons suffering from intermittent fever. i| According to the investigations of L. Senff,! the urine of animals temporarily (two or three hours) contains sugar after they have been made to inhale carbonic oxide. Ewald** brought on glycosuria ia rabbits and dogs by inject- ing nitrobenzol. Ktilz tt also succeeded in producing glycosuria in dogs and rabbits by injecting various substances. Inosite (compare § 27) has been found in the urine repeatedly of late, but always only in pathological cases, sometimes ac- companied by grape sugar, sometimes with albumen in nephri- tis albuminosa. Its source and importance are still unknown. * Schmidt's Jairb., Band 87, p. 281, and Band 97, p. 3, et seq. f Beitrage zu der Frage iiber die Glycosurie der Schwangeren, Wochnerinnen und Saugenden, Dorpat, 1861. JRecherches sur I'urine pendant la lactation, Gfaz. med. de Paris, 1873, No. 43 and 45. § A. Vogel, Deutsches Arciiv f. blin. Med., 1872, x., p. 103. II E. Burdel, De la Glycosurie ephemere dans les Sevres palustres, Union med., 1873, Nro. 105, p. 368, et seg. 1 Inaugural-dissert., Dorpat, 1869. ** Centralblatt f. d. med. Wissensch., 1873, Nro. 52. •f-f Beitrage zur Hydrurie und Melliturie, HabUitationsschrift, Marburg, 1873. Digitized by Microsoft® 406 SEMIOLOGY OF HUMAN UBINE. It appears, however, to come from the glycogen of the liver, for in puncture of the fourth ventricle of the brain in animals or in a corresponding organic disease of the brain inosuria is sometimes produced instead of glycosuria. Cases of inosuria are described by Gallois,* Schultzen.t and others. Inosite was also detected in the urine in a case of polyuria with softening of the medulla described by Mosler.:|: A few other substances which have been found in the urine in isolated cases, such as lactic acid (see § 30), various vola- tile fatty acids (see § 31), benzoic acid (§ 32), which occurs only in decomposing urine, sulphuretted hydrogen (§ 34), allantoin (§ 35), have at present so little practical significance that a dis- cussion of them here is unnecessary. We shall speak of cer- tain substances later, as leucin, tyrosin, etc., when they occur under circumstances which are of interest to the practitioner. (§ 112 and § 133.) § 105. Accidental Abnoemal Constituents. Under this head are comprised various unusual constituents of the urine which are derived from the food, drink, medicines, etc., and which pass into the urine either changed or unchanged, thus rendering it abnormal, but without the abnormity having a pathological significance. We have already in different places spoken of these accidental constituents of urine, their detection and signification. (§ 56, p. 190, etc.) They are of more special interest to the chemist . and physiologist : to the former, because they acquaint him with many products of the decomposition of complex organic substances ; and to the latter, in explaining changes which dif- ferent substances undergo in the human and animal economy, and thus throw light on many points concerning the inter- mediate metamorphosis of tissue. Among these substances which occasionally appear in the urine, and which are, at present at least, of more interest to * De rinosurie, Paris, 1864. f Arch. f. Anat., 1863, i., p. 33, et seq. X Virctow's Arohiv, 1873, Ivi., p. 44, et seq. Digitized by Microsoft® UNUSUAL 00N8TITUBNT8 IN THE UBINE. 407 chemists and physiologists than to practitioners, are to be con- sidered small quantities of nitrates and nitrites (see § 21), which doubtless come from the food and drink consumed, and also small quantities of peroxide of hydrogen (see § 22). Both were first detected by Schonbein.* But they have also some importance for the physician, and in time will assume a still greater one. From their presence we may learn that a patient has taken certain food, drink, or medicine. Thus asparagus, oil of turpentine, saffron, cubebs, etc., betray themselves by the odor which they impart to the urine ; many vegetable substances, as rhubarb, senna, certain roots and fruits containing pigment, sometimes also creosote, tar, and santonin (see page 368), when taken internally, betray their presence by coloring the urine ; while other substances which pass into the urine may be detected by a chemical exami- nation. It is still more important to the physician to know whether certain medicines are eliminated with the urine, and if so, in what quantity, since the answer to this question frequently determines whether a patient shall continue the use of such remedies or omit them. (See page 358). In many cases of poisoning, also, the poison may be detected in the urine, and the examination of the latter may be of im- portance at times in forensic medicine as well as in reference to diagnosis and treatment. The following bodies are those whose detection in the urine is of especial interest to the physician : The methods of detecting their presence are often quite com- plicated, therefore an accurate description here would take up too much space, t Lead sometimes passes into the urine after lead poisoning and after the therapeutical use of preparations of lead. Its detection, however, is difficult and is not always successful.:]: Copper may generally be found in the urine after poisoning by copper. (Kletzinsky.) , * Joum. f. prakt. Chemie, 1864, p. 153, et seq., and p. 168, ^t s^q., ■)■ See § 56, and the thorough treatise of Kletzinsky, Wiener medioin, Woch- enschr., 1857 and 1858. Also Mayenpon and Bergeret, Journ. de I'anat. et de physiol., 1872, Nro. 80-98 ; 1873, Nro. 3. X See also Folwarczny, Wiener Zeitschrift, N. f., ii., b. 1859. Digitized by Microsoft® 408 SEMIOLOGY OF HUMAN URINE. It may be of interest to the physician to detect the presence of mercury in the urine in mercurial poisoning and after mer- curial treatment. In the latter case we may wish to know whether the mercury still exists in the economy, or whether it has already been eliminated. For the methods of proving this see page 192. SdJUts of zinc pass readily into the urine, and may be detected in it without difficulty. (Kletzinsky.) NicM, and cohalt, both of which, especially the former, have a poisonous action, may be recognized in the urine. Arsenic and antimony also pass into the urine, an^ may be detected in it by the familiar processes by means of Marsh's ap- paratus. The detection of iodine in the urine, after its exhibition, may sometimes interest the physician by indicating to him whether the economy still contains iodine or not. The amount of iodine in the urine may be very accurately determined quantitatively. (See page 197, and § 71.) The same is true of bromine. (See page 197.) After the internal administration of the carbonates of the alka- lies or vegetable alkaline salts (acetates, etc.) given as diuretics or to neutralize an excess of acid in the urine, it is often important for the physician to have a means which will enable him to de- termine how long such remedies may be given without injury, and when they shall be omitted, and when continued. In such cases the chemical reaction of the urine forms the best indica- tion. As long as the urine has an acid reaction such remedies may be continued without injury, the system is not yet satu- rated with them. If, however, the urine has a distinctly alkaline reaction, not from the presence of carbonate of ammonium, but from an ex- cess of fixed alkalies (see page 377, b), it is best in most cases to omit the remedy, and to allow it to be repeated only after the urine has become acid again. The exhibition of these remedies should occur during the time when the stomach is empty, because during the two or four hours which follow a meal the urine is less acid, and sometimes even alkaline. (See § 127.) Tannic acid passes into the urine as gallic or pyrogallic acid. Alcohol, cariolic acid, and chloroform appear in the urine, and Digitized by Microsoft® UBmABT SEDIMENTS. 409 may be detected in it according to the methods mentioned in §56. The greater part of quinine which has been absorbed, appears relatively soon in the urine again. By far the greatest part is eliminated in the first twelve hours after its exhibition in healthy persons, and in those suffering from fever ; but in the latter, the chief part of the elimination takes place during the second six hours.* For the process of detecting quinine in the urine, see page 204. IV. URINAET SEDIMENTS. §106. By urinary sediments is meant the occurrence of solid sub- stances insoluble in the urine, which, at first, are usually sus- pended in it, and after a longer or shorter time sink and form a sediment. The deposit forms more rapidly and completely the coarser and heavier the solid particles in suspension are, and more slowly and incompletely the finer and lighter they are. Slight sediments, consisting of very small molecules, which subside only with difficulty, and on shaking are very readily dispersed again, are only recognizable by a cloudy appearance and diminished transparency of the urine, and are called turbidities (clouds — nubeculse). Sediments which consist of large particles distinctly visible to the unaided eye, like small grains of sand, are called urinary sand or gravd. Urinary sediments give important information to the phy- sician, and frequently enable him to recognize at once cer- tain changes of the urine, which would otherwise often require a very tedious chemical investigation. Sometimes, indeed, a chemical test is necessary to determine the nature of a sedi- ment, still more frequently a microscopic examination is re- quired, and urinary sediments are among the objects for the accurate diagnosis of which a conscieintious physician frequently requires the microscope. The semiotic importance of urinary sediments is, like that of the urine, a double one. 1. They give information concerning certain changes in the *H. Thau, Deutsches Arctiv f. klin. Med., v., p. 505, et aeq. Digitized by Microsoft® 410 SEMIOLOGY OF HUMAN UBINE. general metamorphosis of tissue in disease. They teach the phy- sician that an unusually large quantity of certain substances is separated with the urine, and, therefore, must be produced in the system; as, for example, hippuric acid, oxalic acid, etc. By their aid we are often able at a glance to learn much, fre- quently with absolute certainty, sometimes indeed only with probability, which is of value to the practitioner, and which the chemist in detei-mining must attain by troublesome investi- gations. 2. They indicate to us certain heal diseases of the uropostic system. Thus, the presence of a purulent sediment indicates suppuration in some part of the urinary apparatus; urinary casts indicate certain morbid changes in the parenchyma of the kidney ; the chemical composition of gravel points out the probable composition of urinary calculi whose presence has been recognized by other means. Some urinary sediments form before, and some after the urine has been passed; the former may give rise to urinary calculi under favorable circumstances, whereas the latter natu- rally cannot. For this reason, in many cases it is of practical importance to determine whether a sediment already existed in the urine when it was passed, or whether it formed in it after- ward. After these general considerations concerning urinary sedi- ments, we will turn our attention to the importance of the indi- vidual constituents. A. Non-Organized Sediments. Sediments op Ueic Acid and Ueates. §107. Sediments consisting of uric acid and urates occur very fre- quently in the urine ; especially in acute febrile diseases, this variety of sediment occurs much more frequently than all of the other sediments taken together. For their detection, see § 43 and § 44. The conditions of their formation are, as a rule, complicated, and it is often difficult in any given case to determine how far one or the other of the causes mentioned below is active. Digitized by Microsoft® UBINABT SEBIMENTS. 411 Uric acid is one of the normal constituents of urine, but it is soluble in it only with difficulty, and in small amount. When, therefore, changes in the urine occur which bring about such a condition that all of the uric acid contained in it cannot be re- tained in solution, the portion not dissolved is separated as a sediment. These changes of the urine, which accompany the formation of uric acid sediments, may be divided into two groups, whose differentiation is of great practical importance : 1. The quantity of uric acid which passes into the urine in a given time (one hour, twenty-four hours) is greater than usual. 2. But if the urine secreted contains less water than usual, or in other words is very scanty, a uric acid sediment may be formed without the absolute secretion of uric acid being greater than usual. A uric acid sediment in the urine, therefore, is not, as many physicians appear to believe, proof that there is an absolute increase in the quantity of uric acid formed and secreted. Such a conclusion is only justifiable when we have ascer- tained, according to § 73, and quantitatively determined the amount of uric acid passed within a given time (a known num- ber of hours), and have found that it is greater than normal. The causes which give rise to the formation of uric acid sedi- ments are usually the following : 1. The urates are much more soluble in hot water than in cold. Consequently urine which is nearly saturated with these salts at the temperature of the human body throws down a sediment of urates on cooling. We frequently see, therefore, urine, which is perfectly clear on being passed, become cloudy from a separation of the urates, when it has lost the tempera- ture of the body and become cool. It is evident that urate sediments cannot easily occur in this way within the body during life, because the urine can never, except in the very rarest cases, undergo the necessary degree of cooling within the body. But it may happen that urine saturated with urates may undergo a further concentration in the urinary passages by endosmosis, so that a portion of its urates are rendered insoluble and precipitate, and thus form a sediment in the urinary passages ; such a case, however, appears to occur but very rarely. Digitized by Microsoft® 412 SEMIOLOGY OF HUMAN URINE. 2. The normal urates are more soluble than the acid salts, and the acid salts are more soluble than free uric acid. Con- sequently a sediment is formed whenever the normal salts in the urine containing them in large quantity are from any cause converted into acid salts or free uric acid. We see this change occur out of the body during the acid fermentation. Uric acid sediments may be formed within the body for the same reason by either an acid fermentation of the urine, or a mutual decomposition of the urates and the acid phosphate of sodium, as has been already described in § 42, or when a very acid urine by a change in the secretion is mixed with the urine already in the bladder which is but slightly acid or even alkaline, in which case the acid urine ab- stracts the base from the normal urates either wholly or in part. It is probable that the fermentation of the urine may also occasion uric acid sediments in other ways than by the forma- tion of acid. The urinary pigments, indeed, appear to aid ma- terially in the solution of uric acid in the urine. Consequently if the urinary pigment is partially altered and decomposed by the fermentation, a portion of the urates will be precipitated from the urine. So much for the theory of the formation of these sediments : we will now turn to their practical importance. Sediments of urates most frequently occur in acute febrile diseases or in febrile exacerbations of chronic diseases. In such cases almost always several of the above-mentioned pre- disposing causes act at the same time : diminution of the watery part of the urine, and consequently of the whole amount of urine, absolute increase of the uric acid, strongly acid urine, and a large amount of pigmentary matter in it. The sediment in such cases usually appears some little time after the urine has been passed, and its occurrence is caused partly by the cooling of the urine and partly by the commencement of urinary fermentatation and decomposition of the pigment matters, in which such febrile urines usually abound. The appearance of such sediments varies very much; some- times they are of a clay color, sometimes brick red, rose or cinnamon colored — under the microscope they usually appear finely granular. They usually consist of normal or acid urates Digitized by Microsoft® URINARY 8EBIMENT8. 413 ■wliose base is sodium, potassium, or ammonium, more rarely calcium. (For their separation, see § 44.) Their simplest diagnostic mark is, that the turbid urine con- taining them becomes clear on being heated and the turbidity returns on cooling. Their importance consists in indicating that certain changes of metamorphosis occur in most febrile diseases (increased for- mation of uric acid and of pigment, together with diminished secretion of water with the urine). They are frequently re- garded as critical. There is reason in this, in so far as the separation of an excess of uric acid from the blood may be a favorable sign, while a retention of it in the blood would pro- duce eyil consequences. They have, however, very often de- cidedly no critical significance, for we frequently see that the chief symptoms of the disease continue unabated for a long time after their appearance. Sometimes such sediments appear in perfectly healthy per- sons when the above-mentioned conditions are present : they occur, for example, after violent bodily exercise, excessive eat- ing, profuse perspiration with consequent diminution in the amount of urine ; also after a night of revelry or a fatiguing ex- cursion on foot in the heat of summer. Since such sediments are almost always formed outside of the body, they only exceptionally give rise to the formation of urinary concretions. It is of no practical importance to determine the hose with which the uric acid is combined in such sediments, that is, whether the sediment consists of urate of sodium, potassium, ammonium, or calcium. The urine more rarely contains sediments of uric acid. These usually occur in large crystals, often apparent to the unaided eye, or in the form of crystalline masses, sometimes alone, some- times imbedded in a sediment of urates. Such sediments may arise when the urine becomes acid from one of the above-men- tioned causes, and every sediment of urates may be artificially converted into a crystalline sediment of uric acid by the addi- tion of an acid. In this case it is important to ascertain whether the sediment has formed after the urine has been passed, or whether it al- ready existed in the urinary passages, the kidneys, or bladder. Digitized by Microsoft® 414 BEMIOLOar OF HUMAN URINE. The latter is quite important, practically, because by its long continuance we have reason to fear that uric acid calculi may be formed in the kidneys or bladder of such a patient. § 108. HippUBic Acn).* We consider hippuric acid under the head of sediments, be- cause it usually appears as a sediment in those cases which interest the physician, and because in this form it is more easily and quickly recognized by means of the microscope than chemi- cally by evaporating the urine, etc. (See § 8.) Sediments of hippuric acid are relatively rare ; under the microscope they usually appear as rhombic prisms, and some- times in the form of needles. (Plate I., fig. 1.) They may be confounded with uric acid crystals or crystals of ammonio-mag- nesian phosphate. They may be easily distinguished from the latter by their insolubility in hydrochloric acid ; and from the former by not giving the murexide reaction characteristic of uric acid. Sometimes a sediment consists of a mixture of uric acid and hippuric acid crystals, and I have occasionally seen needle-shaped crystals of hippuric acid attached like spears to large crystals of uric acid. In cases of this kind it is best to collect the sediment on a filter and then to boil it in alcohol. This dissolves the hippuric acid only and leaves the uric acid undissolved. By evaporating the alcoholic solution we obtain the hippuric acid isolated, in the form of crystals, which may be more carefully tested and determined in the manner de- scribed in § 8. An adequate number of investigations as to the amount of hippuric acid in normal urine, and its variations is not yet at our command. According to those which have been published thus far, the average quantity of hippuric acid in the urine * W. Duchek, Das Vorkommen der Hippursaure im Harn des Meuschen, Prager Vierteljalirsclir., 1854, Band 3, p. 35, et seq. W. Hallwachs, Ueber den Ursprung der Hippursaure im Harne der Pflanzenfresser, Ann. d. Chem. und Pharm., 1858, Band 105, p. 207, et seq. R. Wreden, Quantitative Bestimmung der Hippursaure mittelst des Titrirverfahrens, .Tourn. f. prakt. Chemie, 1859, Band 77, p. 446. A. Lilcke, Ueber die Anwesenheit der Hippursaure im mensch- lichen Harn und ihre Auflandung, Virchow's Archiv, 1860, Band 19, p. 196. J. L. W. Thudichum, Eesearches on the physiolog. variations of the quantity of hippuric acid in human urine, Joum, of the Chem. Society. ' Digitized by Microsoft® UBINABT SEDIMENTS. 415 passed in twenty-four hours, by persons in health, amounts to from 0'17 to 1 grm., but after eating largely of those substances mentioned below, it rises much higher (to over 2 grm.). For further particulars see pages 47, 48. According to Lawson the urine of the inhabitants of tropical countries, at least in Jamaica, is unusually abundant in hippuric acid. The causes which determine the separation of hippuric acid as a sediment are quite the same as those mentioned under uric acid. Importance. Large deposits of hippuric acid occur in the urine of persons in perfect health after they have eaten largely of fruit, and particularly prunes (Duchek), bilberries ( Vaccinium vitis idcea), and mulberries {Mubus chamcemorus) (Liicke) ; also after taking benzoic and cinnamic acids, which are converted into hippuric acid in the body, and as such separated from the urine. The statement of Kiihne, that after the ingestion of succinic acid a large quantity of hippuric acid appears in the urine, could not be confirmed by Hallwachs, Liicke, and Meissner. When the physician finds a large amount of hippuric acid in the urine of sick people, he must first of all ascertain whether it depends on any such cause (as the ingestion of fruit or ben- zoic acid). Tet, without doubt, a large amount of hippuric acid may be found in the urine, caused by morbid changes of the metamorphosis. Thus, hippuric acid has been found in large quantities in the acid urine of fevers, in which, indeed, it has been the chief source of the acid reaction (Lehmann) ; it has also been found in diabetes, chorea, etc. The observations, how- ever, hitherto made concerning the presence of hippuric acid in the urine of the sick, are still very imperfect, and furnish nothing of value for the diagnosis, prognosis, and treatment of such cases. The opinion that a tendency to the excessive formation of uric acid may be removed by the use of benzoic acid, in con- sequence of the uric acid in such a case being replaced by hippuric acid (Ure, Keller), has been proved to be erroneous, and at the same time the proposed administration of benzoic acid as a remedy in the uric acid diathesis is seen to be of no practical value. During the last few years a large number of investigations Digitized by Microsoft® 416 SEMIOLOGY OF HUMAN UBmE. haye been carried on with respect to the sources of hippuric acid in the urine both of human beings and of herbivorous animals, by which it is much more plentifully excreted.* But they have thus far yielded no results which could be practically utilized by the physician. Tet it seems probable that the biliary acids, and consequently the liver indirectly, by their formation in the body play some part.t § 109. Eaetht Phosphates. (Phosphate of Calcium and Aminomo-magnesian Phosphate [Triple Phosphate].) Earthy phosphates very frequently occur in urinary sediments and chiefly in chronic diseases and in alkaline urine, the reverse of the case with uric acid sediments. When the urine is alka- line they are never absent, whether the alkalinity is spontane- ous or has been occasioned artificially by supersaturation of the free acid of the urine with caustic alkali or alkaline car- bonate. Its mode of origin is thus explained : When urine is rendered alkaline by the formation of carbonate of ammonium resulting from the decomposition of urea (compare § 96 and page 161), not only is its phosphate of calcium precipitated, being soluble only in acid fluids and not in alkaline ones, but it also forms by the action of the ammonia on the phosphate of magnesium always present in the urine, a triple phosphate of ammonio- magnesian phosphate, which separates, since it is insoluble in alkaline fluids. Since now all urine, with very rare exceptions, contains both phosphate of calcium and phosphate of magne- sium, the alkaline fermentation produces a sediment in every urine consisting of a mixture of both of these earthy phos- phates. This sediment, according to Neubauer's numerous investiga- tions,J contains on the average 67 parts of phosphate of magne- * Besides the above literature, see especially B. Lautemann, Ann. d. Chemie und Pharm. , 1863, p. 9, et seq., and Meissner and Shepard, Untersuchungen iiber das Entstehen der Hippursaure, Hannover, 1866. f See Baumstark, Berliner klin. Wochenschr., 1873, Nro. 4. J Journ. f. prakt. Chem., Band 57, p. 65, et seq. Digitized by Microsoft® URINABT SEDIMENTS. 417 sium and 33 parts of phosphate of calcium in 100 parts. (Com- pare also § 132.) See § 46 for an account of the chemical and microscopic char- acters of this sediment. The triple phosphate is always dis- tinctly crystalline, and its crystals are usually very well formed and shaped like a coffin lid (Plate II., fig. 3, 5, and 6) ; more rarely (only when it is freshly precipitated) it is less perfect, but even then its groups of crystals are none the less character- istic and closely resemble two fern leaves crossing each other at an acute angle. Phosphate of calcium, on the other hand, usually appears amorphous under the microscope, in ill-defined, highly trans- parent flakes or cell-like spheres, only occasionally crystalline. (See page 169.) Frequently they are so transparent and their contour so badly defined, that some little practice is required to recognize them under the microscope. This is the reason why such sediments when examined microscopically so fre- quently appear to consist of triple phosphate alone, while, as a rule, one-third at least consists of phosphate of calcium. The case is different when the alkaline condition of the urine does not depend on carbonate of ammonium, but on carbonate of potassium, sodium, or some o\h.er fixed alkali. Then no triple phosphate can form, and the sediment appears to consist only of phosphate of calcium. Sometimes, however, crystalline deposits of phosphate of calcium without triple phosphate are formed even in faintly acid urine.* A. Eiesell found a sediment of phosphate of calcium in the urine, which had already formed within the urinary passages, after the long-continued administration of chalk. Importance. It was formerly the idea that sediments of the earthy phosphates were usually associated with an excess of these substances in the urine, and such cases were considered as so-called phosphatic diathesis. This is wholly erroneous : for every urine which is alkaline, and especially if it is ammo- niacal, contains a sediment of the earthy phosphates, so that a sediment of this kind does not by any means indicate an abnor- * Hassall, On the frequent occurrence of phosphate of calcium in the crystal- line form in hum an urine, and on its pathological importance. Proceedings of the Royal Soc, x., 38, I860,, p. 381. Digitized by Microsoft® 418 SBMIOLOQT OF HUMAN URINE. mally increased amount of earthy phosphates in the urine. An increase of the earthy phosphates can only be proved by a quantitative determination of their amount. (See § 76.) At most we can only give an approximate idea of the amount of earthy phosphates in a specimen of urine from the quantity of the sediment ; according to § 91, however, this last process requires much practice and is not very trustworthy. Independently of this approximate determination of the amount of earthy phosphates these sediments have a practical importance. 1. They are usually the first to indicate to the physician that there is an alkaline condition of the urine with its consequences, and to prompt him to investigate its cause more carefully. (See § 96, especially page 377.) 2. In those cases in which the freshly passed urine already contains a sediment of earthy phosphates, it is evident that they must have been formed within the urinary passages, and consequently we may have reason to fear that they may give rise to the formation of phosphatic calculi, if this condition lasts a long time. § 110. Oxalate op Lime. Calcic Oxalate.* Calcic oxalate is of especial importance to the physician as a urinary sediment, because in this form it is much more easily and quickly recognized by the aid of the microscope than by chemical analysis. We shall, therefore, consider here all of the different circumstances which have a bearing on the occur- rence of this substance in the urine. To recognize a sediment of calcic oxalate quickly in the urine, it is best to use tolerably high powers of the micro- * F. W. Beneke, Zur Physiologie und Pathologie des phosphorsauren und oxal- saureu Kalkes, GSttingen, 1850. Ibid., Zur EntwicklungsgescMchte der Oxa- lurie, GSttingeu, 1853. James Begbie, On Stomach and Nervous Disorders as con- nected witb the Oxalic Diathesis, Edinburgh Monthly Journal of Med. Science, August, 1849. Ch. Frick, in Baltimore, Remarques sur la diathfese d'oxalate de chaux et sur son traitement. Gazette des h6pitaus, 37 Septembre, 1849. Gallois, Mem. sur I'oxalate de chaux dans les sediments de I'urine, dans la gra- velle et les calcula, Gaz. med. de Paris, 1859, Nro. 35, et seg. Smoler, Studien liber Oxalurie, Prager Vierteljahrschrift, 1861. M. Seligsohn, Centralbl. f. d. medic. Wissensch., 1873, No. 22, 37, 38, 33. Digitized by Microsoft® UBINABY SEDIMENTS. 419 scope. The sediment is always crystalline, to be sure, but the crystals, as a rule, are very small, usually much smaller than blood or pus corpuscles. The form of the perfect crystal is always that of an envelope (quadrilateral-octahedron, Plate I., fig. 3). The smallest, even under high powers, always appear only as angular points, and on account of this minuteness of the crystals it is usually impossible to recognize a urinary sedi- ment of calcic oxalate with the unaided eye. It is best when we suspect such a sediment to filter the urine, and to carefully scrape the precipitate from the filter while it is still moist. When it is placed under the microscope the practised eye will immediately recogruze the crystals of calcic oxalate, as a rule mixed with epithelium, mucus, and fragments of fibres of the filter, and sometimes with other crystalline sediments, as for example uric acid. If the diagnosis is doubtful, the other tests for calcic oxalate given in § 45 will confirm it. By this method we can discover the slightest traces of calcic oxalate in the uriue, and we cannot be more certain by chemi- cal means. Still, calcic oxalate may occur iu solution in urine which contains no trace of sediment. (See page 165.) Games and Importance. The causes of the occurrence of cal- cic oxalate in the uriue may be sought in the following facts : 1. Oxalic acid and calcic oxalate form a constituent of many articles of diet in the vegetable kingdom (wood sorrel, com- mon sorrel, the familiar fruit of- the Solanum licopersicum, inown by the name of love apples), and of many medicinal agents. (Leaving out of account the occasional therapeutical use of oxalic acid and its salts, oxalates are contained in the root of rhubarb, gentian, saponaria, etc.) Oxalic acid gains entrance into the body in this way, and is separated again by the urine either wholly or in part as calcic oxalate. 2. Oxalic acid is frequently formed as a secondary product by the decomposition of animal, vegetable, or mineral sub- stances. Thus it is formed by the oxidation of uric acid, kreatinin, leucin, etc.; by the imperfect oxidation of sugar, starch, and salts of the vegetable acids, whereby these, instead of being wholly transformed into carbonates, become in part oxalates which contain less oxygen. It is, moreover, probable that oxalates may be formed from carbonates and bicarbonates, when a part of their oxygen is removed from them by a process Digitized by Microsoft® 420 SBMIOLOOY OF HUMAN UBINE. of reduction. These facts in a measure explain why oxalic acid may be formed in the human system under favorable cir- cumstances ; thus after taking carbonated drinks (champagne, seltzer water), in disturbances of the respiration where the supply of oxygen is diminished, after eating sugar in excessive amount, etc., although the special conditions under which this formation takes place are still undiscovered. According to O. Schultzen,* human urine normally contains in twenty-four hours about O'l grm. of calcic oxalate. (Accord- ing to Neubauer it is sometimes quite free from it; see page 168.) In a few cases of icterus, however, this amount increased fivefold. The question has been repeatedly raised how it happens that calcic oxalate, which is nearly insoluble in water, can pass through the walls of the vessels in the kidney and get into the urine. Some investigations by Neubauer t and Modderman| give information on these points, and show that calcic oxalate is somewhat soluble in the acid phosphate of sodium, and also that chloride of sodium, sulphate of sodium, chloride of potas- sium, etc., and even urea aid in its solution, though in slight degree. What importance, with reference to the diagnosis, prognosis, and treatment of disease does the presence of calcic oxalate ia the urine afford? In this relation we must distinguish two classes of cases : 1. If the urine for a long time continuously, weeks or even months, contains large quantities of calcic oxalate, there exists a so-called oxaluria, oxalic acid diathesis. This condition always demands the careful attention of the attending physician for two reasons. a. Because of the danger, under such circumstances, of calcic oxalate calculi, so-called mulberry calculi, being formed in the kidneys or bladder. b. And on account of the evil effects which oxalic acid may have on the system generally. It is known that oxalic acid taken internally in large amount exerts a poisonous action, not * Quantit. Bestimmung des oxals. Kalkes im Harn, Archiv f. Anat. und Physiol., 1868, p. 719, et seg. \ Archiv f. wissenschaft. Heilknnde, 1858, p. 1, et seq. i Schmidt's Jahrb., Band 125, p. 145, etseq. Digitized by Microsoft® UBINABY 8EDIMENT8. 421 only locally on the portion of the intestine with which it comes in contact, but also generally on the heart and nervous system. From this circumstance it becomes probable, theoretically, that a large formation of oxalic acid within the body may also be productive of dangerous consequences. Many physicians, es- pecially in England and America (Prout, Begbie, Frick, and others), have observed and described such cases of oxaluria. As little attention has hitherto been paid to this form of oxaluria ia Germany, it appears desirable to give here in out- line the very clear description of this disease as given by Beg- bie.* He says: There is a numerous class of patients, mostly persons in the prime of life and belonging to the male sex, ordinarily of a sanguineous or melancholy temperament, unaccustomed to vig- orous exertion, usually belonging to the higher classes of so- ciety and accustomed to indulgence in the luxuries of life, especiajly of the table. They suffer from indigestion, from its mildest to its severest forms. Often no apparent disease is present, but only the discomfort which imperfect digestion and defective assimilation bring about — a feeling of weight and pressure at the pit of the stomach, with flatulence and palpi- tation a few hours after meals. More serious symptoms, how- ever, frequently appear, which are not confined to the digestive apparatus, but exert a very profound influence on the nervous system and threaten the mind of the patient. Such patients are usually capricious, sensitive, and irritable, or dull, despon- dent, and melancholic ; they are frequently worried with a fear of some serious disease threatening them, as consumption or disease of the heart, and on this account are not rarely very deeply disturbed mentally. In milder cases we observe in these patients the anxious bearing and general appearance of one whose health is disturbed — the tongue is coated, the skin dry, and the pulse irritated ; in inveterate cases, a dirty, dingy coun- tenance, increasing emaciation, falling out of the hair, tendency to furuncles, carbuncles, psoriasis, and other cutaneous diseases ; dull, deep-seated pains in the back and loins, haemorrhage from the intestine and bladder, incontinence of urine, and impotency. The progress of this affection may be slow and varied : under * Loo. cit. Digitized by Microsoft® 422 SEMIOLOGY OF HUMAN URINE. the influence of proper diet and appropriate treatment, com- bined witli pure country air, the disorder may be arrested, and, even by appropriate therapeutic treatment, entirely removed. If, however, it he neglected or badly treated, the affection will surely expose its victim to all of the dangers and sufferings of a calculus in the kidney or bladder, or to the still worse conse- quences of a malignant organic disease. The source of this affection is to be sought in the accumula- tion of oxalic acid in the blood. This poison is separated from the blood by the kidneys, and its separation in the form of calcic oxalate gives us a means of recognizing the disease, and thus inducing a cure by tolerably simple and efficacious treat- ment. According to Begbie, this treatment is as follows : Long con- tinuance in a proper diet of meat, milk, mealy vegetables, with the exclusion of saccharine substances ; warm clothing and luke- warm baths ; as drugs, nitrate of potassium, hydrochloric acid in doses of twenty drops two or three times a day, or in the following formula: IJ. Acidi muriatici dil., acidi nitrici dil,, syrupi aurantii aa iss, aquse Siss, of which one teaspoonful is to be taken in a wineglassful of water before meals. Beneke * describes the injurious influence of oxalic acid on the body even more forcibly. He believes that the phosphate of calcium is dissolved by it and removed from the body. The deficiency of phosphate of calcium which is thus brought about results in a diminution of the organic process of cell-formation. Distinct proof is as yet wanting, however, that the symptoms described above as belonging to the oxalic diathesis really do depend on an accumulation of oxalic acid in the blood, and the assumption of an oxalic acid diathesis is, therefore, declared by many, as Lehmann, Gallois, and Smoler, to be quite improper. If, however, we recollect that oxalic acid undoubtedly possesses a distinct poisonous influence on the body when given in large doses, and that every observant physician with much practice has had opportunity to observe cases which quite correspond to the description given by Begbie (I have met with several such my- self), it would appear justifiable to advise practitioners not to neglect those cases in which large quantities of calcic oxalate *Loc. cit. Digitized by Microsoft® URmABY SEDIMENTS. 423 appear for a long time continuously in the urine, and, more- over, to investigate carefully its causes (disturbances of tte respiration with diminished absorption of oxygen, immoderate eating of sugar, disturbances of any other intermediate meta- morphosis), and to carry out the treatment recommended above. 2. On the other hand, it is certain that all of the cases in which calcic oxalate is observed in the urine do not come under the category described. Where only traces of this salt are found in the urine, or when large quantities of it appear only tempo- rarily, as is often observed in the course of certain acute and chronic diseases, the danger spoken of above is not to be feared. The physician here has the task of investigating the cause of this occurrence : whether, perhaps, food or medicine containing oxalic acid gives rise to it ; or whether demonstra- ble changes in metamorphosis are the cause. In such cases the prognosis is not so bad, and we have only rarely to fear the bad results of oxalic acid described above. But it appears advisable here also, after we have obtained the causes of the abnormal condition, to combat it at once by proper treatment (especially substituting an animal diet for a largely vegetable one), and thereby obviate the possible evil consequences. § 111. Cystin.* The practical signification of cystin is of relatively small im- portance, since it seldom occurs in the urine. We only know at present that cystin sometimes gives rise to the formation of calculi. In such cases it always appears as a urinary sediment, and for this reason we mention it here, though cystin may also exist in solution in the urine. Whether the formation of this substance in the body is in any way injurious by producing alterations of the intermediate metamorphosis is not yet determined. It is not probable, how- ever, since, according to experience, cystin may be present in the urine for years without disturbing the health when a cystin calculus is not formed. * A. Fabre, De la cystine, etc. , Paris, 1859. Jul. MiiUer, Archiv d. Pharmaoie, 1852, p. 328, et seq. Toel, Annal. d. Chemie u. Phaijnacie, Band 96, p. 24, et seq. Bartels, Virchow's Archiv, 1863, p. 419, et seq. Digitized by Microsoft® 424 BEMIOLOQT OF HUMAN URINE. For the detection of this body in the urine by chemical and microscopic examination, see § 47. The causes which give rise to its formation in the body are still quite unknown. The large amount of sulphur which it contains (more than 26 per cent.) indicates its relation to taurin, and we are, therefore, led to presume that perhaps the liver plays a role in its formation. Indeed, Scherer has found cystin in the liver, a proof that this substance, like urea, uric acid, etc., is not formed in the kidneys but elsewhere in the body, that it is taken up by the blood and separated again from it by the kidneys. Marowky * observed a case in which the presence of cystin in the urine was combined with almost complete chronic acholia, and supposes that a vicarious elimination of the taurin, which contains sulphur, took place by the kidneys in the form of cystin. Future investigations, let us hope, will yield information as to the significance of the appearance of cystin in the urine, and the more intimate conditions of its formation. It is an interesting fact that in the tolerably rare cases in which cystin has been found in urinary calculi and sediments, it has been present in a large proportion of the cases in several members of the same family. Two cases which I had the opportunity of observing a short time ago, through the kindness of Dr. H. Harnier of Wildungen, confirm this. They were two brothers, young Hollanders, born in the East Indies, both of whom, otherwise well, suffered from cystinuria, which at times increased to the formation of gravel and small calculi. § 112. Xanthin. Hypoxanthin. TYEOsm.t Xanthin (see § 5 and § 49), formerly found only in very rare cases as a constituent of human calculi, afterward found in very small quantity in human urine, etc., has recently been observed also as a crystalline urinary sediment. | The significance of such * Deutsches ArcMv f. klin. Med. , iv. , p. 449, et seq, f Strecker, Anna], d. Chemie u. Pharm., Band 103, p. 108. Stadeler, Ibid., Band 111, p. 38. Scherer, Ibid., Band 113, p. 3o7. Jaillard, Calcul de xanthine, Alger, medic, 1873, Nr. 1, u. Centralbl. f. d. medic. Wissensch., 1873, No. 35. X Bence Jones, Journ. of the Chem. Society, 1863, p. 68, et seq. Digitized by Microsoft® URINARY SEDIMENTS. 425 a sediment for the practitioner depends only on its liability to cause the formation of urinary calculi. The causes which give rise to an increased formation of xanthin in the body and to its existence as a sediment are as yet unknown. Hypoxanthin (sarkin) is a body closely allied to xanthin ; it occurs in small quantity in different organs of the human body (spleen, liver, pancreas), and probably, also, sometimes in the urine. (Strecker.) It must undoubtedly be regarded as a pro- duct of animal metamorphosis, and in its chemical constitution it is very closely allied to uric acid. (Compare page 33.) Still, we know so little concerning its origin and signification at present, that it seems sufficient to merely mention it here. Hosier * lays stress on the appearance of hypoxanthin in the urine as a characteristic symptom of splenic leukaemia. Sal- kowskyt was unable to confirm its occurrence, and the same may be said of E. Eeichardt.J Tyrosin (see § 37 and § 48), is a substance which results from the decomposition of the protein substances. It has been ob- served in different organs of the human body, usually associated with leucin, and in rare cases it occurs as a urinary sediment. When it appears in considerable quantity in the urine it indi- cates alterations of the metamorphosis (excessive decomposi- tion of the protein substances), and thus is of interest to the physician. It has thus far been found in the urine, especially in acute atrophy of the liver, and is to a certain degree charac- teristic of this disease. It was also present in a few cases of leukasmia, typhoid fever, small-pox, etc. (Compare also § 133.) B. Organized Sediments. Mucus AND Epithelium. §113. Urinary sediments consisting of mucus and epithelium are quite important to the practitioner, and as they usually appear together, we will consider them together here. * Virchow's Arohiv, 37, p. 43, et seq. t Virchow's Archiv, 1870, 50, p. 174, et seq. i Jena'sche Zeitschrift, v., p. 389, et seq. Digitized by Microsoft® 426 8EMI0L0GT OF HUMAN UBINE. All urine, even of healthy people, contains a little mucus, which is derived from the mucous membrane of the urinary passages, particularly of the bladder and urethra. In women, not unfrequently, mucus and epithelium from the vagina are mixed with the urine. The presence of a small amount of mu- cus in the urine, therefore, has no pathological importance. It usually appears in the form of a light cloud, which very gradu- ally sinks to the bottom, and is best recognized when the urine is observed in a glass by transmitted light. When there is an abnormal increase in the amount of mucus this cloud increases, and a slimy sediment appears when the urine is left at rest for a time. With a little practice we can determine approximately by observation the quantity of mucus, and, moreover, this method of its estimation not only accom- plishes our object more quickly, but, as a rule, gives better re- sults even than the very complicated chemical processes which are not easily employed by the physician. For the detection of mucus see § 50. Pure mucus is recog- nized under the microscope only with difficulty or not at all, since it forms a perfectly transparent mass which does not catch the eye. Epithelial cells, found mixed with it, are very distinctly recognized, however, from their characteristic ap- pearances. If the mucus is precipitated by alcohol, or acids, however, it is recognized very readily as an indistinctly fibrU- lated mass. -It is rendered more distinct by the addition of diluted tincture of iodine, which not only precipitates, but colors it. If such a specimen of urine is filtered, the mucus remains as a tenacious mass on the filter, and, after drying, has a varnish- like appearance. A small quantity of mucus may remain in solution in the urine even after filtering, and this gives the chemical characteristics of mucin, described on page 17.5. The microscope shows us that the slimy urinary sediment frequently includes, in addition to the epithelium, other foreign matters : spermatozoa, crystals of calcic oxalate, urates, ammo- nio-magnesian phosphate, etc. ; therefore, in all cases in which an accurate diagnosis is required, this supposed mucus must be carefully examined with the microscope. An increased quantity of mucus in the urine indicates to the physician that there is an irritation of the mucous membrane Digitized by Microsoft® UBINABT SEDIMENTS. 437 (blenorrhoea) in some part of the uropoetic system — or in women, of tte genital mucous membrane. This blenorrlicea may form a purely had process, or it may be the result of a general disease. For the latter reason the quantity of mucus and epithelium appears to be increased in the urine not unfre- quently in Tarious febrile diseases — typhoid fever, pneumonia, etc. In a circumscribed blenorrhoea of the urinary passages, the situation of the affection may sometimes be recognized by the shape of the epithelial cells. The desquamated epithelium of the urinary tubvles almost always forms large cylindrical bodies having the diameter and shape of the urinary tubules (epithelial casts). (Compare § 116, 1.) The epithelium of the rest of the urinary passages from the pelvis of the kidney to the urethra is of the pavement variety, arranged in several layers. The most superficial layer consists of more or less flat cells, which in the pelvis of the kidney appear on the whole smaller, less flattened, sometimes irregu- lar and furnished with projections ; while in the bladder they are usually larger and more flattened, and sometimes present grooved depressions on their posterior surface which is turned toward the middle layer. The middle layer consists especially of smaller, more oval and club-shaped caudate cells. The deepest layer of cells consists of still smaller round cells, so- called mucous corpuscles. If we bear in mind these relations, we may frequently be enabled to determine whether the desquamated epithelium contained in the urine came from the urinary tubules or from a lower portion of the urinary passages ; and, in the latter case, whether it belonged to the superficial or deep layers, and whether it came from the pelvis of the kidney or the bladder. When there is a very great increase in the quantity of mucus in the urine, there is almost always a tendency to the acid or alkaline fermentation, which the practitioner must carefully take into consideration on account of the attendant results — in- creased irritation of the mucous membrane of the urinary pas- sages and formation of urinary concretions. . Further, we may observe that pus corpuscles in ammoniacal urine may be converted into a jelly, which bears the greatest Digitized by Microsoft® 428 SEMIOLOGY OF HUMAN URINE. resemblance to nmcus, so tliat the physician frequently sup- poses he has a mucous urinary sediment before him, when in reality it does not consist of mucus, but of pus corpuscles which have been transformed into a gelatinous mass. (See the following section.) § 114. Pus. Recognition. The microscope is always required to distinguish pus in the urine with certainty. With it pus corpuscles are recognized by their shape and size, as well as by the very char- acteristic nuclei which are made clear by the addition of acetic acid. (See § 52.) The abnormcd pus corpuscles described below form the only exception to this. A discrimination between pus corpuscles and so-called mucous corpuscles is neither possible nor of practical importance, since the two kinds of corpuscles are quite identical. Large quantities of pus in the urine always form a sediment. If only a few pus corpuscles are present in the urine, a visi- ble sediment is a long while in forming. To discover the pus corpuscles in this case the urine must either be allowed to stand for several hours in a tall glass and then the lowest layer be examined microscopically, or we must filter it and place that which remains on the filter under the microscope for ex- amination. There are cases, however, in which pus cannot be detected in the urine with certainty, but can only be inferred. This happens when the urine containing the pus is strongly am- moniacal. The pus corpuscles are changed into a ropy gela- tinous mass by the carbonate of ammonium present, and their shape and outline is destroyed. Such a mass is generally taken for mucus and the process causing it regarded as a blenor- rhcea, when in fact it is a pyorrhoea, and the presumed mucus is merely pus, whose corpuscles have been destroyed by the influence of the alkali. Since in every suppuration in addition to the pus corpuscles there is also present a pus serum which contains albumen, it is evident that all urine containing pus also contains a little albumen, which may be demonstrated by the usual tests ; naturally when the urine is alkaline the necessary precautions must be taken. (Compare § 97.) Digitized by Microsoft® UBmABT SEDIMENTS. 429 Importance. Pus in the urine always indicates a suppurative process in the uropoetic system or an abscess communicating with it. Only in women is it possible that pus in the urine may be derived from the genital organs, the vagina, or the uterus. Pus in the urine may be derived from the different parts of the uropoetic system : from the urethra in gonorrhoea, from the bladder, the ureters, the pelves of the kidneys, and even from the parenchyma of the kidney in suppuration of that or- gan. It may spring from several of these parts of the uropoetic system at the same time. The accurate determination of the true source of pus does not always appear to be easy. The following points, however, may prove of some service in the diagnosis : In blenorrhcBa of the urethra a purulent fluid may be pressed out of the urethra between the micturitions. The secretion then appears usually in the form of shreds in the urine. If the pus come from the bladder symptoms of acute or chronic disease of the bladder are always present (strangury, etc.). Suppuration in one or both ureters is accompanied by slight coUcky pains along the course of the ureter. Suppuration confined to the parenchma of the kidney is sometimes accompanied by so slight local symptoms, that it is only discovered accidentally by the continued presence of pus in the urine. Eocarnph. K., a man thirty-six years of age, entered the Gies- sen clinic on account of a rheumatic-gastric fever. He re- covered rapidly, and was about to be discharged, when the sudden occurrence of a tolerably abundant sediment of pus corpuscles in his urine occasioned his retention in the hospital for a short time longer for observation.' This sediment con- tinued for weeks, the patient not having the slightest difficulty of micturition, indeed no symptom which pointed to disease of the uropoetic system. Subsequently pain was felt in the region of one kidney and frequent chills occurred. An intercurrent typhoid fever, which was then epidemic, unexpectedly put an end to the patient's life, and the autopsy showed an almost complete suppuration of the parenchyma of one kidney without any further disease in the urinary apparatus. Digitized by Microsoft® 430 SEMIOLOGY OF HUMAN URINE. It is of great practical importance in such cases to determine whether the pus is the product of a superficial affection of the mucous membrane (catarrhal inflammation), or whether it is the result of a more profound and extensive alteration of the parts. The following facts will assist in deciding this question : The duration of the suppuration. The temporary presence of pus in the urine, lasting only a few days, always allows us to conclude that there is merely a superficial affection. The character of the pus as seen on microscopic examination. Perfectly normal pus corpuscles of quite round shape present- ing on treatment with acetic acid the characteristic double or triple nuclei indicate laudable pus and a simple catarrh of the mucous membrane. Abnormal pus corpuscles, on the other hand, with irregular forms and contours, and which present ir- regular nuclei on treating with acetic acid, or an ill-defined, finely granular mass mixed with irregularly shaped pus corpus- cles and partially destroyed cells, indicate the probable exist- ence of a deep-seated suppuration, ulceration, or tuberculosis. (Compare the following section.) Various substances were formerly included under the head of pus in the widest sense of the word, which could not be dis- tinguished by the unaided eye, and which the microscope alone has now allowed us to distinguish. The recognition of these substances has a great practical significance. Of this class are cancerous and tuberculous masses and urinary casts. § 115. CiLNCEBOUS AND TuBEECULOUS MASSES. Cancerous and tuberculous masses sometimes occur as uri- nary sediment, and are important in indicating to the physician the fact that softening has occurred in cancerous or tubercu- lous deposits in some portion of the urinary organs. Masses of cancer occur in the urine most frequently as the result of cancer of the bladder, more rarely of cancer of the kidney. The cancer is generally of the soft variety, encepha- loid, and, as a rule, appears in the urine in the form of small masses, aggregations of cells — mother and daughter cells — with thick walls or caudate and long spindle-shaped cells. In such cases the urine also usually contains blood and blood coagula. Distinct symptoms of disease of the bladder are always pres- Digitized by Microsoft® UBINABY SEDIMENTS. 431 ent in cancer of that organ : difficulty of micturition, frequently also symptoms whicli point to a simultaneous disease of the rectum, or in women of the vagina, so that the diagnosis usually presents no difficulties. Cancer of the bladder is generally a so-called villous cancer, that is, it is made up of compound branched villi, which are sometimes hollow and consist of a fibrous stroma covered with a layer of variously shaped epithelial cells ; sometimes also it consists of an amorphous base with cells imbedded in it. The detached portions of this cancer of the bladder, which occur as a sediment in the urine of those patients in whom the can- cer has softened and separated, are, therefore, of very various shapes, but at the same time they are very characteristic and are of essential service in enabling us to diagnosticate such a disease with certainty. Fig. 5 and 6 in Plate III. represent a few of the most charac- teristic forms of such cancers as they appear in the urinary sediment. They are in part taken from the valuable work of Dr. Lambl,* and partly from my own observations. Fig. 5, A, represents a large fragment of villous cancer of the bladder, very branched, as it appears with a low magnifying power (from 20 to 50 diameters). B represents the terminal portion of a villous cancer more highly magnified (about 200 diameters). The inner part con- sists of an amorphous fibrous stroma containing numerous oval nuclei and externally covered with a compound layer of epithelial cells. C represents isolated cells from the epithelial layer of such a cancer. They are mostly irregular in form, partly caudate and branched, quite large, and containing a large nucleus. D is a villous cancer of a somewhat different character. Tol- erably large nuclei are enclosed in an amorphous mass which forms warty excrescences. The epithelial layer is wanting. Fig. 6, A. Fragment of a villous cancer consisting of a fibrous (hollow?) cylinder, which is covered with epithelium (in the figure stripped off in places) in the form of small nucleated cells. * TJeber Harnblasenkrebs. Ein Beitrag zur mikroskopisclieii Diagnostik am Kraukenbette mitvier Tafeln. Prager Vierteljahrschr., 1856, Band 49, p. 1, et seq. Digitized by Microsoft® 432 SEMIOLOGY OF HUMAN URINE. B is a mass of large canoer-ceUs with large cell-caTities, thick cell-wall and nuclei ; the latter in some cases is enclosed in the cell-wall (B, c). The cells are partly united by means of an amorphous connective substance into large groups (B, a), and they are in part isolated (B, b, and B, c). C. Fragment of an amorphous, fibrous cancer stroma having spindle-shaped nuclei and elastic fibres, on which larger cells rest — the remains of the epithelial covering — in part well pre- served (aa), in part half destroyed (b). D. Isolated cells probably derived from the epithelial cover- ing of a villous cancer of the bladder; aa, small round cells with nucleoli (or nuclei?) distinctly colored red, and at first sight resembling blood corpuscles ; in large masses forming a urinary sediment resembling blood, but not affected by acetic acid ; bb, large, irregular, partly caudate cells, having reddish nuclei containing nucleoli. They are found mixed with the small cells (nuclei?), aa. (Compare § 134, case 13.) Cancer of the kidney, on the other hand, is usually much more difficult to diagnosticate. Sometimes when cancer-cells are present in the urine, we can determine the existence of the disease by negative signs, as all symptoms pointing to a disease of the bladder are wanting ; sometimes also we can determine it by percussion through an enlargement of one or both kidneys. Masses of tubercle in the urine resemble pus when seen with the unaided eye, but they may be distinguished from it by their microscopic appearance. They consist of irregular pus corpuscles in addition to an ill-defined detritus — ^fragments of cells, necrosed connective tissue and elastic fibres, imperfect nuclei, and an indistinct, finely granular mass with which frag- ments of cholesterin crystals are sometimes mingled. The seat of the tubercular deposit which gives rise to urinary sediments of softened masses of tubercle is the mucous membrane or the submucous tissue ; it may take place in the bladder, the ure- ters, or the calices of the kidney. In affections of this kind, which have lasted a long time, the tubercular deposit, as a rule, extends over a great portion of the mucous membrane of the urinary tract, from the kidneys even to the bladder. The following histories of patients may serve to give infor- mation concerning the diagnosis of tubercular deposits in the uropostic system : Digitized by Microsoft® URINABY SEDIMENTS. 433 1. A young man, twenty-five years old, souglit aid at my clinic for an affection of the bladder which had troubled him for a year. Micturition was difficult and painful, the urine was sometimes bloody, and deposited a sediment on standing, which contained blood and pus corpuscles partly normal and partly abnormal. (The latter were not perfectly round, but were angular and knobbed ; when treated with acetic acid, they did not show normal nuclei, but were either wholly without nuclei or showed only small irregular nucleoli.) Besides this the sedi- ment contained an irregular, granular, amorphous mass, in part finely divided, in part combined into larger masses up to the size of the head of a pin. A careful examination, moreover, showed that the prostate was enlarged, very sensitive on pressure, and that there was an advanced tuberculosis of the lungs. The patient had never suffered from gonorrhoea or chancre. A diag- nosis of tuberculosis of the bladder and prostate was made, and on the death of the patient a short time after from increase of the lung trouble, the diagnosis was confirmed by the autopsy. 2. A man thirty years old, who had always been healthy, was seized with occasional attacks of pain, which passed from the region of the left kidney down to the bladder and terminated in very urgent and frequent calls to micturate. These par- oxysms lasted several hours, and were repeated again after in- tervals of complete intermission which sometimes covered a few days only, and sometimes lasted for several weeks. Half a year later a swelling formed in the left testicle, this broke and led to the formation of a fistula which obstinately resisted all attempts to heal it. The urine never contained gravel or con- cretions, such as would lead to the suspicion of calculus of the kidney, but after every attack it deposited a slight sediment consisting of pus cells, which, as in the former case, were very irregular, and when treated with acetic acid presented no nor- mal nuclei. Here, also, there was found in addition an ill-de- fined amorphous granular mass of the same appearance as that presented by tubercle-detritus under the microscope. This circumstance, together with the accompanying disease of the testicle, admitted of the diagnosis of tubercular deposit in the left ureter. * * Compare also Kussjnaul, Wtirz burger med. Zeitschr., 1863, p. 24, et seq. 28 Digitized by Microsoft® 434 semiology of human- ubine. § 116. Ueinaey Oylindebs. Eenal Casts.* Urinary sediment, consisting of renal casts and cylinders, is of great practical importance in giving us information which will enable us to form a diagnosis and an opinion concerning certain diseases of the parenchyma of the kidney. This sedi- ment can be recognized with certainty only by a microscopic examination. Its forms and characteristics have been already described in § 53 ; we must return to this subject again, how- ever, in order to explain its importance under certain circum- stances. This sediment consists of long tubular or cylindrical bodies, which are formed in the urinary tubuli of the kidneys, espe- cially the tubes of Bellini in the medullary portion, and which take the form of these tubules more or less, and to a certain ex- tent form casts of them. The chief forms under which the ele- ments of this sediment appear are as follows : 1. Epithelial Casts: Tubular masses of epithelial cells like those obtained by scraping with a knife a section of a fresh kidney through the medullary portion, and examining the fluid obtained microscopically. (See Plate I., fig. 4.) The epithelium ■of the tubules of Bellini is thrown off in coherent masses by a pathological process and is evacuated with the urine. Besides these larger epithelial tubules, single epithelial cylinders (cau- date cells) are frequently found which are derived from the ■calices or the pelvis of the kidney (Plate I., fig. 4) ; sometimes also pus corpuscles are present. 2. Grcmular Benal Casts (Plate I., fig. 6). These are solid cy- linders, resembling those just described in form and size, but of a finely granular appearance. Sometimes they enclose single epithelial cells, more frequently blood corpuscles, pus corpus- cles, as well as different kinds of crystals met with in urinary sediments, especially calcic oxalate. Blood corpuscles, pus cor- puscles, or granule cells are very often found mixed with them in the sediment. *L. Eovida, TJeber das ■Wosp-n der Hamcyliuder in Molescliott's Unters. zur NaturleliTe, xl., p. 1, et seq. A. Burkart, Die Harncylinder, GekrSnte Preis- schrift, Berlin, Hirschwald, 1874. H. Senator, Ueber die im. Harne vorkom- menden Eiweisskorper, etc., ilber Harncylinder nnd Fibrinauaschwitzung, Vir- cliow's Archiv, 1874, Is., p., 466, et seq. Digitized by Microsoft® UBmABT aEDIMENTS. 435 3. Hyaline Renal Casts (Plate I., fig. 5). These are also solid cylinders, like the last, but they are so pale and transparent that it is very difficult to distinguish them under the microscope from the surrounding fluid. They are rendered more distinct by adding to the urine a little solution of iodine in iodide of potassium or in glycerine, which gives them a brownish color. There are many transitions between the forms 2 and 3 ; the hyaline casts, for example, take up pus corpuscles here and there, or granular molecules or fat drops and fat granules, and thus resemble the granular form. Moreover, we should observe the diameter of these casts. Sometimes the diameter is small, -^^^ of a line ; in other cases it is larger and may reach -jV of a line or more. Sometimes the casts are of unequal diameter, they are small at one point and broader at another, varicose or flask-shaped. Since casts and cylinders in many cases occur only in small numbers in the urine, to ascertain with certainty whether any are present or not, we must either allow the urine to stand a long time and examine the sediment microscopically, or what is still better, we must filter it and place the magma which re- mains on the filter under the microscope, as this will contain all of the casts and cylinders. It is a good plan to color the urine by adding a solution of iodine in iodide of potassium, so as not to overlook any of the transparent hyaline cylinders, which are so difficult to see. Sometimes forms are met with in the urinary sediment which somewhat resemble granular casts, and which may be erroneously mistaken for them. Such are cylindrical, sausage-shaped bodies which consist of masses of fine mole- cules. (Plate II., fig. 2.) They are found chiefly in albuminous urine, or in urine which has stood a long time and has already undergone partial decomposition. They result from a finely granular precipitation of albumen, mucus and the like. The skilled observer readily distinguishes them from true granular casts by their less regular shape. Importance. Eenal casts and cylinders always spring from the urinary tubules of the kidneys, especially from the tubules of Bellini in the medullary portion, and they indicate disease of these tubules. They are usually regarded as a sure sign of so-called Bright's disease. Since, however, the name " morbus Brightii " is at most only a somewhat indefinite collective term, Digitized by Microsoft® 436 SEMIOLOGY OF HUMAN URINE. under which all varieties of disease of the renal parenchyma are usually included, it is insufficient for a careful diagnosis, prognosis, and treatment. We will attempt in the following pages to ascertain a little more accurately the indications of the different forms of these products. Epithelial casts in the urine indicate that a separation of the epithelium of the tubules of Bellini (desquamative nephritis) is taking place. This process may be temporary without leav- ing any further consequences behind. Therefore a urinary sediment which consists merely of epithelial casts and which disappears again in a few days allows of a favorable prognosis. If pus corpuscles are found mingled with the epithelial casts, this points to a more severe imflammatory process (pyorrhoea) either in the parenchyma of the kidney or in the calices and pelves of the kidneys. Granular and hyaline casts, on the other hand, always indicate a graver disease of the parenchyma of the kidney, which gene- rally assumes a chronic course. The hyaline casts probably arise from an exudation of a fibrinous fluid into the renal canals with subsequent coagulation of the fibrine (croupous inflammation). The granular casts are formed either by a further metamorpho- sis of the exudation in the urinary tubules or by a degeneration of the glandular epithelium lining the tubules. According to Eovida the colorless renal casts do not consist of fibrine and are also different from other kinds of albumen. Senator also does not consider the albuminous renal casts of all diffuse diseases of the kidneys as blood or exudation fibrine, but as products of the disturbance of nutrition of the glandular epithelium. The larger the quantity of casts in the urine and the longer time they are present, the more extensive is the degeneration of the kidney apt to be, and as a rule, therefore, the more un- favorable is the prognosis. If there is quite an amount of fat in the casts, and if it lasts a long time (recognizable as fat drops and granules imbedded in the casts), we may infer that the degeneration of the kidneys inclines to a fatty one. When blood continues to be present in the casts, or in the urine containing casts, we may conclude that there is especially a disease of the vessels of the kidney — rigidity, fatty or amy- Digitized by Microsoft® UBINABT SEDIMENTS. 437 loid degeneration of the renal arteries, especially of the vascu- lar coils, which, as Malpighian bodies, project into the origins of the renal tubules. Casts of very" small diameter indicate a probable contraction and narrowing of the renal tubules, and unusually large ones indicate a dilatation of the renal tubules. Casts of very un- equal diameter, with bulgings and contractions, allow of the conclusion that there is a varicose or distended condition of the renal tubules. When, as often happens, several of the modifications men- tioned occur together, we have reason to assume that the pathologico-anatomical changes in the kidney are very compli- cated. Bhod corpusdes occur not infrequently as a urinary sediment. (Compare § 51 and § 99). We have already spoken of their significance to the physician in § 99. If they are in moderate quantity, together with renal casts and pus corpuscles, we may conclude that we are dealing with a case of a commencing or an advanced nephritis parenchymatosa or Bright's disease. In rare cases granules or flakes of blackish-brown pigment are found in the urinary sediment. S. von Basch * describes them as pale flocculi thickly filled with dark brownish, finely granular pigment, some of which have the shape and size of cells, while the most of them are much larger and are of irregu- lar shape. They indicate a plugging and rupture of the renal vessels produced by the melansemia.t (See page 394.) § 117. Infcsoeia. Fungi — (Kyesteine).J Fungi and infusoria rarely exist in fresh normal urine ; they must, therefore, gain access to it accidentally through unclean vessels, etc. They occur frequently, however, in urine which * A case of melansemia. Wiener medic. Jahrb., 1873, ii. f Further details may be found in J. Vogel's Kraukheiten dor harubereiten- den Organe, in E. Virchow's Handbuch der Pathologie und Therapie, Band vi., p. 600. XA. Hill HassaZl on the development and signification of Vibrio lineola, Bodo nrinarius, and on other fungoid products, etc., in urine. Lancet, Nov. 1859, ii. 21. Digitized by Microsoft® 438 SEMIOLOOT OF HUMAN UBINE. has been kept a long time, and are almost always present in urine wMch has undergone decomposition. L. Pasteur* rightly calls attention to the fact that the germs of these fungi and infusoria always get into the urine from without, and are not formed in it by the so-called generatio sequivoca; moreover, it is usually after the urine has been passed that the fungi and infusoria appear, and they are the true cause of the acid and alkaline fermentations as well as of the decomposition of the urine. Urine from which these germs have been carefully excluded may be kept without decompos- ing. Since they are in any case the chief cause of a putrid decomposition of the urine with all of its results, such as de- composition of the urea, precipitation of many of the urinary constituents, irritation of the mucous membrane of the urinary passages, etc., we must take heed that such germs do not gaia access to the urinary passages by the passage of unclean cathe- ters, etc., and by rapidly increasing there bring about the evil consequences mentioned. The infusoria are almost always very small, and are recog- nized under the microscope, when quite high powers are used, by their motion. They consist either of punctiform monads or of rod-like vibriones and bacteria. Rarely they are larger, roundish, resemble mucous cells and have thread-like appen- dages (Bodo urinarius — Hassall). They are found chiefly in putrid urine which contains albumen, mucus, blood, or pus, and are practically important, since they may favor or even set up putrid decomposition of such a specimen of urine. If they have formed already within the urinary passages, their germs have probably always obtained entrance from without, fre- quently in the manner described, by the introduction of un- clean catheters. In all such cases, however, we must satisfy ourselves that the vibriones have not come from accidental mixture of putrid matters with the urine after its passage, from unclean vessels, or similar sources. Fungi usually appear in the urine in the form of roundish or oval cells (spores and sporules), which are sometimes united in rows like a rosary (torula form) — less frequently they appear in the form of simple, compound or branched threads (thallus, * Comptes rendus, 1860, i., p. 841. Digitized by Microsoft® UBINABT 8EBIMENT8. 439 mycelium). These latter usually do not occur until after the urine lias been kept a long time, and, therefore, they are not of much practical importance. Of these fungi which occur in urine, those which are of chief interest to the physician are : 1. The torula-like fungus observed by Von Tieghem and de- scribed on page 188, on which the alkaline fermentation of uriae is said to depend. The conditions of its origin. and de- velopment, however, require a more accurate investigation. 2. Yeast spores (Hormiscium sacchari), which occur only in saccharine urines, and may, therefore, be utilized for the detec- tion of glycosuria. They are also roundish or oval cells, which sometimes enclose a nucleus ; they are, however, somewhat larger than the preceding (O'OOi to 0"007 mm. in diameter). They increase by budding to torula-like rows, which are com- posed of from two to four cells. (See Plate 11., fig. 2, and page 189, fig. 5.) 3. Sarcince (vide page 189, fig. 6). It appears to have quite as little real specific significance in the urine as it has in other cavities of the body (stomach and intestines, lungs), where it appears more frequently ; it is probably, therefore, to be re- garded as an accidental parasite. The presence of sarcinse in the bladder probably favors the decomposition of the urine, produces alkalinity, a deposition of the earthy phosphates, etc., and therefore it has a practical interest.* Other fungi which are occasionally observed in urine which has been kept a long time belong to the most common forms, as penicilium, etc., whose spores are very widely disseminated, and may develop in the urine under 'favorable conditions when they have gained access to it. They are, therefore, without significance to the physician. Under this head belongs the so-called Kyesteine which was thought to be present only in the urine of pregnant women ; and therefore that it could be utilized as a means of diagnosti- cating pregnancy. This name was applied to a pellicle which forms on the surface of urine after it had stood for a long time, usually several days. Microscopic examination of it shows, however, that it consists of very various elements, for the most * Besides tie literature already mentioned, see also Sarcinse in the Urine (F. Bateman, Lancet, 1867, i., No. 6). Digitized by Microsoft® 440 SEMIOLOGY OF HUMAN URINE. part of a large mass of vibriones with fungi, of crystals of am- monio-magnesian phosphate, small drops of fat, etc.; it is, there- fore, no simple substance which requires a special name. More- over, this pellicle does not occur exclusively in the urine of pregnant women, but is also found frequently in that of women not pregnant, and even in that of men, so that it has no diag- nostic value for pregnancy. § 118. Speematozoa. Spermatozoa can be detected in the urine only by the aid of quite high powers of the microscope. They are readily recog- nized by their peculiar tadpole shape. Since they rarely occur in large numbers, often only a single one being found in the urine, it is necessary to allow the urine to stand at rest in a coni- cal glass (champagne glass) for a long time in order to find them with certainty ; this is accomplished by carefully pouring off the upper part of the urine, and then examining microscopically the lowest part which contains the spermatozoa. Their importance is self-evident. In the urine of men they always indicate that a discharge of semen has taken place either from coitus or masturbation ; sometimes they lead to the detec- tion of onanism. In the urine of women they prove that coitus has taken place, provided that there has been no admixture of semen, intentional or otherwise, with the urine. The immature spermatozoa sometimes found by Clemens in the urine * indicates to the physician that an unusually power- ful or an immoderately long-continued irritation of the genital apparatus has occurred, whereby not only mature but also im- mature spermatozoa have been ejected (onanism, excessive coi- tus, etc.). In rare cases entozoa also occur as a urinary sediment, when they have gained access to the kidneys or some other part of the urinary passages, and are passed with the urine. Of these the most frequent in Europe are : EccMimcoccus cysts, usually numerous, of the size of a pea, hazel-nut, walnut, * Henle and Pf Buffer's Zeitsohrift, 1846, v., p. 133, and Deutsche Klimk, 1860, 30. See also page 187. Digitized by Microsoft® URINARY SEDIMENTS. 441 and larger, formed of a structureless membrane and filled with serous fluid. Sometimes when these bladders are not sterile, the characteristic ecchinococcus heads and hooks may be seen with the microscope. Most of the eechinococci which pass off with the urine are located in the kidney, though eechinococci may also be situated elsewhere, in the pelvis, etc., make an opening into the urinary organs, and thus pass off with the urine. The following example will show how difficult it may some- times be to properly estimate such cases. A middle-aged man, otherwise well, suffered for years with a difi&culty which oc- curred in paroxysms after longer or shorter intervals, and which indicated a disease of the urinary passages: there was occa- sional pain in the region of the left kidney, with albumen and pus, and sometimes also a moderate amount of blood in the urine. Various diagnoses were made by different physicians who were consulted, and corresponding courses of treatment were pursued (courses at Yichy, Karlsbad, etc.), but with no im- provement ; they, together with the ever-increasing fear that a serious renal disease existed which would shortly terminate fatally, rather reduced the patient. A careful examination of the urine passed during the attacks frequently showed the pres- ence of small membranous shreds, which were recognized by the microscope as fragments of a sterile ecchinococcus bladder. Since percussion gave only a moderate enlargement of the left kidney and the natural passage of the ecchinococcus bladders had commenced in a relatively favorable way, a not unfavorable prognosis was given. The patient, freed from his anxiety and under treatment which, besides mild diuretics, had as its chief object the avoidance of matters which could be injurious, re- covered in a comparatively short time.* In Egypt the eggs of the Distomum hcematobium are found as a urinary sediment with tolerable frequency. They are oval, from 012 to 0-13 mm. long and from 0'04 to 0-05 mm. broad, and are characterized by a sharp point at one end, or by being armed with a pointed spine on the side.t * For further information see J. Vogel, Krankheiten der hambereitenden Or- gane, in Virchow's Pathologie und Tterapie, Band 6, S. 691, et seg. f For more particulars on this point and for the symptoms which they cause, see Bilharz, Zeitschrift f. wissensch. Zool., iv., p. 59, 73, and 454. The same author, Wiener medic. Wochenschr., 1856, Nr. 4 and 5. Digitized by Microsoft® 442 SEMIOLOGY OF HUMAN UBINE. T. R Lewis* found in the urine and blood of several persons suffering from chyluria in Calcutta a peculiar entozoon (named Filaria immitis by Cobbold).t * Centralbl. f. d. med. Wissenscliaft., 1873, No. 31 and 30. f For an account of a few other entozoa which are passed with the urine in very rare cases, the reader is referred to our work on the Diseases of the Uri- nary Organs, in Virchow's Pathol, und Ther., Band 6, p. 555. Digitized by Microsoft® DIVISION SECOND. QUANTITATIVE CHANGES IN THE URINE. §119. Much less attention has been paid by the practitioner, until quite recently, to the quantitative changes of the urine, espe- cially the increase or diminution of the normal constituents, than to the qualitative changes of this fluid previously con- sidered. The reason of this was partly because generally less importance has been hitherto attached to the chemical element in disease and in the changes of metamorphosis, and partly because the methods formerly used in such investigations were very difficult, tedious, and lengthy, requiring much appara- tus, indeed frequently a complete laboratory, so that they were employed almost exclusively by chemists. By the re- cent introduction of new methods, however, especially the volumetric methods, many of the investigations of this sort have been greatly simplified, so that they may now be per- formed by the practitioner quite quickly, and without any large amount of apparatus. At the same time the importance, ne- cessity even, of the quantitative estimation of the various pro- cesses of metamorphosis in disease becomes evident; and it is to be hoped that in proportion as the importance of such investigations for purposes of diagnosis, prognosis, and treat- ment are brought out more distinctly, practitioners will avail themselves more frequently of them. I trust the following at- tempt to demonstrate the importance of such investigations to the practitioner, as far as it is possible at the present time, will assist somewhat in bringing them into more general use. The quantitative changes of the urine may be divided into two groups, according as they are more or less readily deter- mined. 443 Digitized by Microsoft® 444 SEMIOLOGY OF HUMAN UBINE. I. Those whicli may be discoTered without an exact chemical analysis, and which, on account of their easy detection, are of especial value to physicians. II. Those which require a quantitative chemical analysis to detect them, and whose determination is, therefore, more diffi- cult and complicated. I. THE QUANTITATIVE ALTERATIONS OP THE URINE WHICH ARE EASILY DEMONSTRATED. Under this head belong : The quantity of the urine ; the solid residue, and the specific gravity of the urine ; and the color. The estimation of all of these is so easy, requires so little appa- ratus and so little time, that no practitioner is excusable for neglecting them in those cases in which they may contribute something to the more complete insight into a diseased pro- cess. § 120. Quantity of Ueine.* The process proposed for estimating the quantity of urine has been already described in § 57. It is most .easily deter- mined by measurement ; the determination by weight is more laborious. The estimation of the quantity of the urine is only of value when we also know the time during which it was passed. It is best to collect the urine which has been passed either during twenty-four hours, or during every hour, or at least to calculate the quantity passed for this period. In accurate estimations of the quantity of urine it is absolutely necessary that the physi- cian should assure himself that all of the urine passed has been really collected, that none of it has been lost at stool or in any other way, and that no water, etc., has been po.ured into the urine vessel. A simple estimate of the quantity of urine, without weighing or measuring it, may sometimes give the physician important indications in certain cases, but it does not serve for accurate investigations. Since graduated urine-glasses can be easily and cheaply obtained at the present time, and since they are, moreover, much better adapted for displaying the color, trans- * J. "Vogel, Archiv fiir gemeinschaftliche Arbeiten, Band I., pi 104, et seq. Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 445 parency, sediment, and other characteristics of urine, than por- celain or earthen vessels, the physician should give them the preference in all cases in private practice in which the examina- tion of the urine is important. In order to ascertain the average quantity of urine passed in chronic diseases (the quantity in an individual case), we must not be satisfied with measuring it for a single day ; for during that short period accidental influences may easily increase or diminish the quantity. The urine must rather be measured for several days in succession and the average be taken for twenty- four hours. To ascertain the influence of any temporary circumstances it is best to calculate the quantity of urine passed per hour. The determination of the quantity of the urine forms the basis of the quantitative estimation of all of its constituents. It is also in itself important oftentimes in showing the activity of the kidneys, and especially their power of separating water from the system. In many cases it is important to the physician to determine the relation of the quantity of urine to the amount of the pul- monary exhalation, perspiration, and fseces ; for many hints are thus obtained which may be of service in judging of the state of the disease, in giving a prognosis, and in recommending the treatment. Thus, in most chest, heart, and skin diseases a diminution of the urinary secretion, with an accompanying in- crease of the pulmonary exhalation, is an unfavorable sign, and the duty of the physician in such cases is to increase the uri- nary secretio^ in order to relieve the diseased organs. Con- versely in most diseases of the kidneys, at least in their com- mencement, our object is to lessen the activity of the kidneys and diminish the quantity of urine by stimulating* the other secretions. When the urine is permanently much increased (polyuria, diabetes), the determination of its quantity is the first and most important means of ascertaining the nature of the disease. To determine in any given case whether the quantity of the urine is increased or diminished, it is not sufficient merely to measure the urine ; we must also know how far the amount found exceeds or falls short of the normal quantity. "We must, therefore, learn the normal quantity passed by the individual. Digitized by Microsoft® 446 SEMIOLOGY OF HUMAN URINE. If very accurate determinations are required, as for example in physiological experiments as to the influence of dififerent agents on the urinary secretion, the normal quantity of urine passed by the individual must always be ascertained by trial at the time of each experiment. In investigations on the sick, on the other hand, we must, as a rule, be content with approximate determinations, and substitute for the amount of urine of the individual, which usually cannot be determined, the average quantity determined by numerous observations on dififerent in- dividuals. In practice, however, little attention is oftentimes paid to this principle ; because, on the one hand, physicians are apt to trouble themselves too little with such investigations, and hence deduce from observations, quite correct in themselves, false conclusions on account of judging them by an incorrect standard ; and, on the other hand, over-exact physiologists un- justly reject approximate investigations made on patients, be- cause they do not appear to them to be sufficiently accurate. It seems desirable, therefore, to illustrate this subject by a few examples. We know that the average quantity of urine passed by an adult in health in an hour amounts to from 60 to 70 cc, but that it may vary between 30 and 100 cc. If now we find that in an individual, the normal amount of whose urine we are not ac- • quainted with, an average hourly quantity of 80 cc. is passed under the influence of some medicinal agent, we may fairly conclude that the medicine employed had a diuretic effect ; the conclusion, however, is not absolutely certain, because, as we have seen, 80 cc. are within the limits of the normal variation in the quantity of urine. Still less are we able from this ex- periment to decide to what extent the urine has been increased by the medicine employed, because the . ordinary amount of urine passed by the individual may be either somewhat above or below the average. To obtain a trustworthy result in such a case we must ascertain as accurately as possible, by very numerous observations, the average quantity of urine passed by the individual at the time of the experiment, and then compare the quantity thus obtained with the quantity passed under the influence of the medicine. If we find, after repeated trials, that a person who has par- Digitized by Microsoft® qUANTITATIVE CHANGES IN THE UBINE. 447 taken largely of fluids (water, tea, etc.) passes an average of 400 cc. of urine per hour, we may be assured, without accurately knowing the normal quantity of urine passed by the individual in question, that the fluids which have been taken by him have had a diuretic effect. The 400 cc. of urine which are passed per hour are so much in excess of the average quantity that it becomes a matter of no importance whether the average quan- tity passed by the individual is 40, 60, or 80 cc. per hour. Quite the same thing often occurs in patients. The average quantity of urine passed in twenty-four hours by healthy, well- nourished adults amounts to from 1,400 to 1,600 cc. ; in those who drink a smaller amount of fluid, 1,200 to 1,400 cc. If, there- fore, we find that a patient passes only 400 cc. in twenty-four hours, we may be sure that the quantity of his urine is essen- tially diminished ; the diminution is so considerable that it is a matter of small importance to ascertain whether the normal quantity of urine passed by the person in question is 1,200 or 1,400 cc. We may conclude, with equal certainty, that the amount of urine is abnormally increased in a patient who passes 2,500 or 3,000 cc. of urine in twenty-four hours, although we have not accurately measured the normal quantity of urine passed by that individual. Numerous observations show that in healthy adults the ave- rage quantity of urine passed is — a. In twenty-four hours : By well-nourished persons who drink abundantly, from Ij4:00 to 1,500 cc. By those who drink less 1,200 to 1,400 cc. b. In one hour : By those who drink freely 60 to 70 cc. By those who drink less freely 40 to 50 cc. If we calculate the average quantity of urine for the weight of the body, we find that an adult passes an average of 1 cc. of urine per hour for each kilogram (= two pounds) of the weight of his body. Calculating according to the height of the body, we find that an adult passes hourly 40 cc. on an average for each 100 cm. Digitized by Microsoft® 448 SEMIOLOGY OF HUMAN UBINE. People who do not lead very regular lives are the subjects of very considerable fluctuations in the daily and hourly quantity of urine. The daily quantity may vary between 1,000 and 3,000, and the hourly quantity between 20 and 200 cc. These variations depend in great measure upon different ex- ternal influences, upon the food, and especially upon the drink, and upon an increase or diminution of the perspiration ; and in persons who live regularly the variations are confined within much narrower limits than in those who live irregularly. Moreover, we observe tolerably constant variations in the hourly quantity of urine at different times of the day. In this country (Germany) the average hourly quantity of urine is greatest in the afternoon hours, after the chief meal or dinner (77 cc. in an hour) ; it is the smallest during the night (58 cc. in an hour), and a medium quantity is passed in the forenoon (69 cc). We must, therefore, in all cases in which we wish to determine accurately the influence of any agent upon the se- cretion of urine, take into consideration the time of day at which the experiment was performed. It is very difficult to answer the question as to what in- fluences increase or diminish the quantity of the urine, and chiefly because a large number of agents are simultaneously at work increasing or diminishing it, and these aid or neutral- ize each other, so that it is very difficult to isolate and deter- mine the amount of each single influence. The secretion of urine is decidedly increased by free drink- ing, though certainly not to the extent asserted by Falk, who stated that the whole quantity of water drunk is separated by the urine. "We all know that a person who drinks a great deal, when exposed to a high temperature, and at the same time takes considerable exercise, sweats profusely, and accurate ex- periments have shown that under such circumstances a larger portion of the water taken passes out of the body through the skin than through the kidneys. The most different fluids, such as ordinary water, carbonated water, beer, wine, tea, etc., when taken in sufficient quantity, act as diuretics on people in health (but not always in disease) ; undoubtedly, however, the differ- ences which exist in the diuretic action of the different fluids are very difficult to determine accurately, since a large number Digitized by Microsoft® QUANTITATIVE OHANOES m THE UBINE. 449 of very variable circumstances modify their action, and, more- over, individual peculiarity plays an important part. Examples. The quantity of urine passed per hour in healthy men was increased by plentiful drinking of water from between 60 and 70 cc. to 300, 400, 600 cc, and even more. In twelve students, who, for the sake of experiment, drank large quantities of beer, the average quantity of urine secreted per hour amounted to 473 cc. ; the minimum quantity was 212, the maximum 838 cc. 0. Westphal* and K. H. Ferberf found that the exhibitioA of water increased the secretion of urine in dogs as well as in man, the secretion gradually increasing remained stationary for some hours and then returned to the normal standard. They also found that the whole of the water which was drunk was not eliminated with the urine, but that a very considerable portion of it always passed off with the perspiration. The quantity of urine is diminished by lessening the absorp- tion of fluid (abstaining from drink until great thirst is expe- rienced), but not in the same degree that it is increased by free drinking. Example. Four male individuals from 20 to 25 years of age were placed on dry diet. The average hourly quantity of urine which they passed, which with ordinary diet was 86 cc, sank to 87 cc. (Hosier.) All causes which aid the elimination of water from the body by other channels diminish the secretion of urine ; especially copious sweating, abundant watery stools, and much vomiting. On the other hand, all causes which lessen the other watery secretions of the body increase the quantity of the urine : much atmospheric moisture, which impedes cutaneous and pulmonary exhalations, and other agents, such as cold, which diminishes the cutaneous perspiration. Causes of this sort seldom exert an unmixed influence, so that the quantity of urine which is observed in such cases can seldom be regarded as a standard of the action of a par- ticular agent. For this reason I shall omit numerous examples which I might quote. To obtain a general idea of the activity * Virchow's Archiv, I860, Band 18, p. 509, et seq. f Arch. d. Heilkunde, 1860, i., p. 344, et seq. 29 Digitized by Microsoft® 450 SEMIOLOGY OF HUMAN UBINE. of these influences tlie following considerations may be of ser- vice. The quantity of water passed with the urine is about equal to the whole amount eliminated by the skin, the lungs, and intestines, taken together. If, therefore, an increase or diminution of one of these latter functions is to exercise a con- siderable influence on the amount of urine, it must necessarily be quite a large one. The intensity of the activity of the kidney, doubtless de- pendent on the nervous system, exerts a very decided influence on the quantity of the urine, especially the amount of blood pressure existing in the vessels of the kidney. This is gene- rally greater during great bodily and mental activity, and less- ened during rest and sleep. It is also increased and diminished by different diseases. A very large number of observations made on seven men gave as the average quantity of urine passed in the night 58 cc, and on the other hand 73 cc. as the average during the day. That rest alone was the only cause of this difference is shown by the fact "that persons who work during the night, either bodily or men- ially, pass as much urine then as they do during the day. The influence of increased action of the kidneys on the secre- tion of urine is strikingly shown in cases of dropsy. In a ■dropsical patient who passes on an average only 400 cc. of urine in twenty-four hours, the secretion under the influence of diure- tics or even by the simple increase of the general strength may Teach in a very short time 3,000 or even 5,000 cc. per day, with- out any essential change in the mode of life, quantity of drink, etc. If we attempt to formularize the different influences on which the quantity of the urine depends, it may be expressed about as follows : The factors which espedaUy determine the quantity of urine se- creted are : 1. The more or less watery condition of the blood. The quantity is increased by a free addition of fluid to the blood, and it is diminished by an abundant separation of water. 2. The excretory activity of tJie kidneys. This is certainly not a simple force ; it depends on the degree of arterial blood pressure generally, and especially on the tension in the renal arteries, particularly the glomeruli ; on the greater or less ease with Digitized by Microsoft® qUANTITATITE CEANaES IN THE UBINE. 451 which the urine flows from the tubules ; on the state of the nervous system generally, and on the state of the renal nerves in particular, etc. All of these different forces, however, have not yet been accurately determined ; we, therefore, group them all under the above general expression. Quantity of Urine in Disease. The quantity of urine passed by the sick frequently varies much from the normal. These deviations are sometimes more of an accidental nature dependent on various causes; some- times they are constant and essential, so that they are always the same in diseases of the same kind. The abnormal states of the urine of the latter class are of great importance to the physician in regard to diagnosis, prognosis, and treatment. The most important of these are the following : 1. At the height of aU acute fehrUe diseases the quantity of urine is considerably diminished, except in a few rare instances, as during the paroxysms in most cases of intermittent fever, but it increases again when the intensity of the disease has passed. During convalescence the quantity of urine becomes normal or even exceeds this point. Hence in all such diseases the quantity, especially in connec- tion with the color (see § 122) of the urine, gives important in- dications. Thus a constant daily diminution of the quantity of the urine indicates that the intensity of the disease is increas- ing — a continued low quantity of the urine (below 800 cc. per diem) shows that the intensity of the disease has not diminished — while a steady increase of the quantity of urine shows that the force of the disease has been broken. An explanation of this general law, which is of importance as regards the state of metamorphosis in febrile diseases, can not be given as yet. A careful examination of the urine in all of these cases shows that the diminution of the quantity of urine depends almost exclusively on a diminished separation of loater by the kidneys; in what way this is brought about, whether by diminution of the blood pressure, by lessening of the nervous influence, or by some other unknown circumstances, we do not venture to determine. This diminution of the quantity of the urine, with very few exceptions, takes place in all acute febrile diseases, as pneu- monia, pleurisy, typhoid fever, rheumatism, gastritis, pysemic Digitized by Microsoft® 452 SEMIOLOGY OF HUMAN URINE. fever, etc., and every physician has so good and frequent an opportunity to observe it, that examples appear to be quite superfluous. The following will serve to show the progress of the urinary secretion in such cases. A., an attendant in my clinic, whose normal quantity of urine had been accurately determined for a long time beforehand, became ill with typhoid fever. The quantity of urine which before averaged about 1,800 cc. daily, constantly diminished during three days until it reached 200 cc. ; in the next five days it gradually increased up to the normal amount, and then it in- creased beyond this to 2,200 cc, and finally gradually returned to the normal standard. In a patient suffering with pneumonia the quantity of urine at the beginning of the sickness diminished to 500 cc, then it constantly rose in the course of ten days to the normal standard, exceeded this, and reached 3,000 cc, when it gradually returned to the normal amount and with slight variations remained nor- mal. 2. Toward the/atoZ termination of diseases both acute and chronic, the quantity of urine frequently either constantly di- minishes, or it remains very low for a long time with variations. This, however, is not always the case : sometimes the quantity of urine diminishes only a little up to the time of death (it re- mains over 800 cc. per diem). This, without doubt, is due to the fact that in many cases the immediate cause of death is a gradual failure of nutrition ; while in other cases it is suddenly brought about by nervous disturbances, interference with the pulmonary or cardiac movements, etc. 3. The quantity of urine passed in chronic diseases, especially in dropsy and in those cases which are classed under the com- mon name of diabetes (better polyuria), is of especial importance to physicians. As a rule, in dropsical patients, the quantity of urine, and especially the separation of water by the kidneys, is essentially diminished. As a result, its constituents, which should be eli- minated, especially water, are retained in the blood, and either the exudation of watery fluids into the cellular tissue, serous cavities, etc., is favored, or the absorption of fluid already pres- ent is rendered more difficult. Experience shows that persons suffering from dropsy are cured more especially by increasing Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 453 tlie secretion of urine (diuretics) ; and tlie greater or smaller amount of urine, as a rule, in dropsical patients, is not only tlie safest guide in making the prognosis, but it also furnishes indi- cations for treatment. We usually designate with the name of diabetes those dis- eases in which the quantity of urine, for a long time, largely exceeds the normal standard. To judge of these cases, how- ever, it is necessary to ascertain the amount of the solid con- stituents contained in the urine, and not merely the quantity. (Compare the following section.) In many cases of polyuria the nervous system evidently has a great influence on the increase of the urinary secretion.* 4 It is self-evident that in the sick all those things must be taken into account which may have an influence on the quantity of urine in health. Thus, in disease, the quantity of the urine may be temporarily increased by free drinking, by a watery condition of the blood in combination with an increased activity of the kidneys. More frequently it is diminished. Temporarily, by sweating, diarrhoeas, and other watery evacuations ; perma- nently, as a rule, in consequence of their taking less food than people in health, and because the metamorphosis in general is diminished. § 121. Solid Eesidue and Specific Geavitt of the UBmE.t 1. The methods of estimating the quantity of the solid resi- due of urine, its amount of water, and other constituents which volatilize at 100°, have been already described in § 59. The pro- cesses given there, however, are both tedious and difficult, so that they can seldom be used practically ; still we must employ them in all cases in which as accurate an estimation as possible of the quantity of water or of the solid residue of urine is re- quired. For the purposes of the physician, who only requires approxi- mate results, these processes may be replaced by a determina- tion of the specific gravity of the urine, and from this its amount of solid constituents may be inferred. This method of deter- * See W. Ebstein, Deutsoh Arch. f. klm. Med., 1873, xi., p. 344, et seq., and P. Hosier, Virchow's Archiv, 1873, Ivi., p. 44, et seq. \ 3. Vogel, Archiv fiir gemeinschaftliche Arbeiten, i., p. 419, et seq. Digitized by Microsoft® 454 SEMIOLOGY OF HUMAN URINE. mining tlie specific gravity lias been explained in § 58. For the physician's use the so-called urinometer, a glass hydrometer, is the most convenient, as it may be simply allowed to sink in the urine ^rhich is to be tested. (See page 212.) If the urine were a fluid which, independently of its variable amount of water, always contained the same constituents in the same proportion, we could estimate with tolerable accuracy its quantity of solid constituents from its specific gravity, just as the percentage of alcohol or of sulphuric acid is ascertained. Unfortunately this is not the case, the quantity of the difiierent constituents of the urine increases and diminishes in very vari- able proportions ; therefore we cannot obtain from the specific gravity of the urine accurate results as to the amount of solid constituents, but they are always more or less uncertain. The best formula by which to reckon the quantity of solid constitu- ents in the urine from its specific gravity is Trapp's. It con- sists in doubling the two last figures of the specific gravity ob- tained. The product gives the number of grams of solid con- stituents contained in 1,000 cc. of the urine in question. Thus, a urine of I'OIO specific gravity contains 20 grm. of solid con- stituents in 1,000 cc. ; of sp. gr. 1-015, 30 grm. ; of 1-020, 40 grm., and so on. In order not to draw erroneous conclusions as to the amount of solid constituents from the specific gravity of a urine we must first of all bear in mind how great the accuracy of this method is, and also how great is its liability to' error. Numerous ex- periments made by myself, and comparison with the observa- tions of others, have shown me that, in estimating the solid residue of a urine from its specific gravity in specimens of nor- mal urine, we may easily have an error of one-tenth, or even one-seventh ; and in the urine of the sick, especially when the specific gravity is high, the error may be even greater, amount- ing to one-fifth or one-quarter. If in three successive days there are found 55, 50, and 60 grm. of solid constituents accord- ing to Trapp's formula, these differences are so slight that they fall within the limits of error in the observations, and we should not be justified in saying that the patient on the day on which the calculation gave 60 grm., passed the most solid constituents with the urine, and on that in which 50 grm. were found, the least was passed. Such a conclusion would only be justified Digitized by Microsoft® QUANTITATIVE GHANGES IN THE URINE. 455 wlien the quantity of solid constituents of the urine had been determined by a more exact method. If, on the other hand, we find from the specific gravity that a person who has passed, on an average, about 60 grm. of solid constituents with the urine, secretes on one day only 30, we are perfectly justified in conclud- ing that he has passed on that day much less solid material than usual, since the difference is so great that it cannot be, ex- plained as an error of observation. On the other hand, it would be very rash to assert that the person in question had passed only one-half the ordinary quantity of solids, and it is only to be regarded as approximate, since a direct determination would give, perhaps, 28 or 36 instead of 30 grm. Since all such determinations of the solid residue from the specific gravity give such inaccurate results, it appears to be quite immaterial whether we make use of Trapp's coefficient (2) or of a different one (for example, Haser's=2"33, or of Christi- son's=2"3), since the difference between them (between Trapp's and Hiiser's is only one-sixth) still comes within the limits of unavoidable errors of observation. W. Kaupp * also found Trapp's formula correct, while the accurate investigations of Neubauer (see page 221, 3, and page 347) are more in favor of Haser's formula. For estimations and conclusions at the bedside of the patient, which can never be very exact, the coefficient 2 commends itself by its simplicity and the readiness with which it can be reckoned in the head. In such cases differences in the temperature of the urine, if they do not exceed a couple of degrees, may be disregarded. 2. What practical conclusions can the physician draw from the quantity of solid residue and the specific gravity of the urine ? First the specific gravity enables us to calculate the weight of a measured quantity of urine. The calculation is simple : 1-000 cc. of urine of specific gravity 1-024 weigh 1-024 grm., and so on. Further the specific gravity of the urine and the quantity of solid constituents found either directly by analysis or calculated often give important indications concerning many quantitative changes of metamorphosis ; especially in the quantity of solids and of water, which have been separated by the urine under certain circumstances in a certain time. * Archiv fiir phys. Heilkunde, 1856, Heft 4. Digitized by Microsoft® 456 SEMIOLOGY OF HUMAN UBINK To judge of these conditions it is of prime importance for us to know the exact normal. The average specific grayity of the urine in male adults in the normal condition is about 1"020. From this we may reckon that in an average daily quantity of urine of 1,400 or 1,600 cc, an average daily quantity of 55 or 65 grm. of solid constituents are eliminated. A man passes on an average 4'1 grm. of solid constituents per 100 kilograms of weight and 1'5 grm. per 100 centimeters of height per hour. These figures form the basis for recognizing and forming an opinion of many abnormities of the metamorphosis in disease. In most acute diseases the daily separation of solid consti- tuents by the urine is somewhat less than in health ; instead of 60 it amounts to only 40 or 50 grm. Since such patients as a rule, however, only take fluids which contain little solids, they are in a condition similar to that of persons fasting, the separa- tion of the solid constituents of the urine takes place in them at the expense of the body, they consume their own flesh, as it were, and become thin. The estimation of the amount of solid residue of the urine is of especial practical interest in all cases in which the secretion is much increased in quantity (polyuria). These cases may be separated into two well-marked groups according to the greater or less quantity of solid constituents contained in the urine. 1. The abundantly secreted urine contains much more solid material than in the normal condition, much more in fact than is introduced into the body by means of the food. Hence arises a disproportion of nutrition, the patients in question become weak and emaciated. The cases belonging to this group are included under the further subdivisions according as the urine contains sugar (diabetes mellitus), or is free from it but contains an abnormally large amount of the other solid constituents (diabetes insipidus). 2. The excessively abundant urine has a low'specific gravity and contains relatively few solid constituents. "Water is the constituent which is chiefiy separated from the body by it, and it is very readily restored again ; no emaciation results, there- fore, and no hectic; on the contrary, the process is sometimes beneficial, and promotes the removal of diseased products, as in Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 45'7 many cases of hydrsemia and dropsy. This form of increase of tlie urinary secretion (hydruria) must, therefore, be most care- fully distinguished from true diabetes. Examples. A woman, 31 years of age, who had suffered for a long time from symptoms of anaemia and hysteria, with giddi- ness, headache, spasms of the cervical muscles, sensitiveness of several of the vertebrae, pale face, etc., passed an increased quantity of urine (the average of a fourteen days' observation amounted to 3,080 cc. daily). The specific gravity of the urine was only slightly diminished, and the calculated quantity of solid constituents in it amounted to a daily average of 87 grm., a quantity much greater than normal (the maximum in 24 hours was 136 grm., which was more than double the normal quan- tity). In this case, which was one of true diabetes insipidus, the increased separation of the solid constituents of the urine combined with a deficiency of nourishment was evidently the chief cause of the symptoms, which rapidly improved under a more generous diet in addition to the use of iron and other tonics. A man, 35 years old, of herculean frame, suffering from rheu- matism of the neck, passed a very large quantity of urine (the daily average of observations lasting twenty-four days was 2,983 cc), but its specific gravity was very low (between 1-005 and 1-012), and the daily average amount of solid constituents reckoned from it amounted only to 42 grm., therefore less than normal. This man did not appear to suffer at all from the in- creased secretion of urine ; it evidently was "not diabetes, but merely hydruria. Many other conclusions concerning the quantitative changes of metamorphosis in disease may be drawn from the specific gravity and quantity of the solid constituents of the urine ; thus, for example, the relation of the amount of solid constituents which are eliminated with the urine to that of those which are eliminated by the skin and lungs may be ascertained ; when the quantity of solid matters taken with the food is l^nown at the same time, we obtain the relation of the amount which is taken into the body to that which passes out of it, etc. The knowledge of all of these points is of great importance in rela- tion to the metamorphosis in disease, and the necessary means are of such a nature as to be procured in every clinic without Digitized by Microsoft® 458 BEMIOLOar OF HUMAN TJMINE. difficulty ; but so little lias been done tlius far in this field that no special conclusions have been drawn as yet. The specific gravity of the urine, moreover, gives the phy- sician indications which, though of themselves not sufficient to lead to any definite conclusions in diagnosis, prognosis, and treatment, are yet serviceable by leading to further investiga-. tions. The following considerations belong under this head : Urea is the chief solid constituent of the urine as a rule ; it usually equals all of the others together and sometimes exceeds them. Therefore, the specific gravity of the urine may also serve to point out approximately the quantity of urea contained in it. Such an estimation of the quantity of urea is, however, very uncertain, and considering the ease with which it may be directly determined quantitatively it will never replace the latter method. When urine is far below the normal in quantity and has a high specific gravity, we may generally infer in the case of healthy persons that its condition depends on abstinence from drink or upon an abundant loss of water by increased perspira- tion ; and in the case of disease it depends on an acute disease. When the amount of urine is increased far beyond the normal and the specific gravity is low, we may conclude that an excess of fluid has been taken. In the sick who are suffering from hydremia or dropsy such a condition of the urine is a very favorable sign, and indicates that the system is making an effort to get rid of the excess of water collected in the blood or tissues. If a superabundant amount of urine of high specific gravity is passed, or if it has only the ordinary specific gravity, we must bear diabetes mellitus in mind and test for sugar; or, when it contains no sugar, the case is diabetes insipidus. If the quantity of urine is not increased, or if it is diminished even and. yet its specific gravity is low, we may suspect the ex- istence of some impediment to the secretion of urea, and have reason to fear the results of retention of urea in the body (uraemia) in such a case. In most chronic diseases (except diabetes) the solid residue of the urine is diminished ; an increase of the solid residue in- dicates a more active metamorphosis and better nutrition, and is, therefore, a favorable sign as a rule. On the other hand, an increase of the solid residue of the Digitized by Microsoft® QUANTITATIVE CEANOBS IN THE URINE. 459 urine at the height of acute diseases is usually an unfavorable sign, because the inanition, which always occurs in such cases, is thereby increased and favored. The sj)ecific gravity of the urine, as a rule, in acute febrile diseases, is in inverse proportion to its quantity ; the specific gravity increases at the height of the attack in proportion as the quantity diminishes ; it afterward falls with the increase of the quantity, and sinis during convalescence frequently below the normal. We must be careful, however, not to infer too much from the specific gravity of the urine alone, and not to utilize it, for example, for the dififerentiation of diseases which in other respects present similar symptoms. It has been stated that the specific gravity of the urine in- creases much less in typhoid than in other acute diseases, and especially in inflammatory diseases; and that in the true ty- phous stage it amounts to only 1'017, while in acute affections of the brain, especially meningitis, from the beginning to the end, it is much higher (1"028 to 1'035). This difference, there- fore, may be utilized in cases where it is difficult to distinguish between a typhoid and such affections of the brain.* Such an attempt to distinguish diseases by a single phenomenon, and one which, in comparison with the other symptoms, is very un- important, belongs to the now happily ended ontological method of comprehending diseases. In the distinction and classifica- tion of diseases by this method, just as in the division of animals and plants into genera and species, only the external appearance , with its thousand accidents is regarded instead of their essen- tial character, their causes, connections, and interdependence being kept in view. Such a use of a single symptom can only be justified, when not only the fact itself has been surely estab- lished by numerous observations, but also its cause and signifi- cation have been explained, and its necessary relation with the disease in question. In the case before us, there is wanting not only a satisfac- tory explanation of the diminution of the specific gravity of the urine in typhoid, but also the truth of the fact, except in isolated cases, is only problematical. According to my very numerous investigations of the urine of typhoid patients, its * A. Ziegler, Die TJroscopie am Krankenbette, Erlangen, F. Enke, 1861, p. 8. Digitized by Microsoft® 460 SEMIOLOGY OF HUMAN UBINE. specific graTity, at least in tlie cases in which considerable fever and a certain degree of reaction is present, was high dur- ing the acme of the disease, as the following cases show : (The figures in all cases show the specific gravity of the whole quantity of urine passed in twenty-four hours during the height of the disease. The blanks, which sometimes cover several days, arise from the impossibility of always collecting the whole quantity of urine passed, unmixed with fasces, in patients who frequently pass urine involuntarily with their stools. This is a circumstance which renders accurate quan- titative examinations of the urine in typhoid at the height of the disease difficult or even impossible.) Case 1. Third day, 1-019— 1-029— 1-031— 1-026— l-024^(two days omitted)— 1-019— 1-021— 1-016. Subsidence of the fever. Convalescence. Case 2. Fourth day, 1-028- 1-029— 1-027— (one day omitted) —1-028—1-027. Death. Cases. Second week, 1-019— 1-020— 1-018— 1 -020-1 -022— 1-026. Slow convalescence. The specific gravity of the urine in typhoid, as in other acute diseases, falls as the fever diminishes and convalesence is es- tablished. On ,the other hand, I must admit that there are cases of typhoid in which the specific gravity of the urine, even during the height of the disease, is low, sometimes even far below the normal, as the following examples show : Case 1. 1-008— 1-014— 1-017— (two days omitted)— 1-017— 1-027—1-015—1-014—1-015—1-014-1-012. Death. Case 2. First week, 1-018 to 1-020. Second week, 1-012 to 1-015 ; then convalescence. Case 3. 1021— 1-020— 1-015— 1-014— 1-010— 1-006— 1 -010— 1-012— 1-013— 1-015—1-011. Convalescence. In all of these cases, however, the fever from the first had a distinctly marked adynamic character, and the general condi- tion of the patients, especially the weak and distinctly double pulse, afforded much more trustworthy signs for distinguishing the case from one of inflammatory affection of the brain and its membranes than the specific gravity of the urine, which, more- over, I have not always found so remarkably high in menin- gitis as Ziegler states it to be. Such a diminution of the spe- Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 461 cific gravity of the urine, moreover, does not occur exclusively ia typhoid ; it also occurs in other forms of fever, when they assume a well-marked adynamic character, as in pyaemia, pu- trid fevers, etc. § 122. The Quantity op Ubinaby Pigment.* The color of the urine and the pigments which cause it have been already spoken of in various places (§ 10, § 61, § 93). It is very difficult, indeed almost impossible, to obtain an accurate estimation of the quantity of coloring matter in the urine cor- responding to the requirements, which we are entitled to ex- pect of quantitative chemical analysis at the present day. I have, therefore, proposed another method, very simple and easy, of determining this substance quantitatively, so that every practitioner can avail himself of it. Although the results are not absolutely exact, but are merely approximate, they afford much that is interesting and valuable for diagnosis, prognosis, and treatment. This method, and the mode of employing it, has already been explained in § 61, and the color table in Plate IV. gives every one an opportunity of using it himself. As objections to this method, since its proposal, have been made by various writers, I will briefly answer them. First, it has been objected that the color of the urine does not depend on one and the same pigment, but on several differ- ent ones. This is correct, and has been already admitted in § 93. But the abnormal colors of the urine described there, whether they are merely accidental, depending on the pigments of rhubarb, senna, etc., or whether dependent on biliary pig- ment, uroxanthin, uroglaucin, urrhodin, and uroerythin, are relatively rare, and, when present, may be readily recognized. In all such cases it would doubtless be a mistake to use the color table for the quantitative estimation of the urinary pig- ment. But these are exceptional cases for which the method is not adapted ; and it can be no reproach to it that this is the case, for it very rarely happens in other quantitative chemical investigations that a method is applicable to all cases. In by far the greater number of cases the urine, especially when it has * J. Vogel, Archiv fiir gemeinscliaftliclie Arbeiten, i., p. 137. Digitized by Microsoft® 462 BEMIOLOar OF HUMAK UBINE. been filtered, contains either none, or only a very small quantity, of such abnormal coloring matters, but. is usually colored by the ordinary urinary pigment (Heller's uropbsein, Thudichum's urochrom, Jaffe's urobilin). Moreover, it has been objected that the shades of color given in the color table do not follow in an exact series, and that by diluting brown or very high-colored urine, we should not ob- tain exactly the same shades of color which pale urine yields ; and, therefore, the statement that a red urine contains thirty-two times, and a brown red one sixty-four times as much coloring matter as a pale yellow would not be exact. I am quite ready to admit that the coloring matter of the urine is not the same thing always and under all circumstances, but that it may pre- sent modifications which exercise an influence both over its coloring power and over the shade of color produced by it ; but this is no reason why we should not use the color of the urine as a means of estimating approximately the urinary pigment, if we do not assume the limits of possible error as too low. Hitherto, notwithstanding the praiseworthy efforts of Scherer, Harley, Thudichum, Jaffe, and others, we have not been able to obtain the urinary pigment in a pure state, so that the estab- lishment of the limits of error in this case is completely arbi- trary. But I believe I am rather above than below the mark, when I assume that the possible error may amount to one- fourth or even one-third of the number found. Variations which exceed these, therefore, indicate with certainty a differ- ence in the amount of coloring matter in two specimens of urine compared with each other, while other variations which are less than these might be neglected. If, for example, the quantity of pigment which a healthy in- dividual passes with his urine in twenty-four hours amounts to four units, and we find that a sick person passes from sixteen to twenty, a considerable increase of the coloring matter in this case is undoubted ; it is at least double or treble. There is also an undoubted diminution, if the calculation gives only one. But if, on the other hand, we should find three and a half or four and a half, we cannot conclude with certainty that there has been a diminution or an increase. On these grounds I consider ' that I may maintain that this method, carefully employed, may give useful results, and that Digitized by Microsoft® QUANTITATIVE CnANQES IN THE UBINE. 463 (for tlie reasons given in the following explanation of its signi- ficance) it may give the physician very important information as to the metamorphosis, or the destruction of blood corpus- cles, information which appears the more valuable because the means which the physician possesses of forming an opinion as to the extent of this kind of metamorphosis in the sick is very limited. The indication which an increase or diminution of the urinary pigment affords to the physician may be derived from the fol- lowing considerations, which indeed are not proved, but are in part hypothetical, and yet are probably correct. There is much reason to believe that a portion of the blood corpuscles in the living body is constantly undergoing a retro- grade metamorphosis and being dissolved, so that its coloring matter, hsematin, is so changed that it finally passes out of the body in the form of urinary and biliary pigment ; therefore, we have in the amount of the coloring matters of the urine and bile taken together a sort of measure of the degree of decomposition of the blood corpuscles. From it, in many cases of disease, the physician can obtain valuable hints and conclusions respecting diagnosis and treatment. It is too soon now to be able to determine how much bipod pigment or how large a quantity of blood corpuscles a certain amount of urinary pigment corresponds to. We know too little as yet about the changes which blood pigment undergoes be- fore it becomes metamorphosed into urinary pigment. For this reason I have preferred to take as a standard of compari- son for ascertaining the amount of urinary pigment an imagi- nary quantity, by fixing 1 as the quantity of urine pigment which 1,000 cc. of pale yellow urine contains, instead of attempting to ascertain the quantity of the coloring matter absolutely by weighing or by comparison with the color of a known quantity of blood corpuscles, such a determination in a short time being too difficult. The reasons for the above hypothesis, that the urinary and biliary pigments are modified blood pigment, are as follows : Blood coloring matter is very difficult to destroy ; we see that ex- travasations of blood in the body, as well as blood which has been subjected to various influences outside of the body, retain their color^th great tenacity, or only undergo slight modifications Digitized by Microsoft® 464 SEMIOLOGY OF HUMAN UBINE. of color. It is not probable, therefore, tliat tlie coloring matter of the blood which has become unfitted for the purposes of the economy is eliminated from the body as a colorless substance, but, on the contrary, there can be scarcely any doubt that it is still more or less colored when it is excreted. Since the only colored excretions of the body are the urine and the stools, we must consider the urinary pigment or the biliary pigment (as it appears modified in the faeces), or both, as formed from the used-up blood pigment. For these reasons many thorough ob- servers, as Scherer, PoUi, Virchow, Harley, and others, have not hesitated to regard the biliary coloring matter, the urinary pigment, or both, as in part educts of the hsematin. Moreover, some observers (Hoppe-Seyler, Maly) have recently succeeded in transforming blood pigment (haemoglobin) by chemical treat- ment directly into biliary pigment (bilirubin) and urine pigment (urobilin). (See page 64.) The quantity of urine pigment which an adult passes nor- mally in twenty-four hours amounts to from 3 to 6 units, or an average 4'8, therefore about 0'2 in an hour, the above unit beiag taken as the standard.* According to B. Lawsonf a much greater quantity of pig- ment is passed with the urine in the tropics (Jamaica), as a rule, than in our latitudes : 12 to 14 times the above unit in twenty-four hours in healthy men. This is the standard for judging the quantity of pigment in the urine in a given case of disease, whether it is normal, in- creased, or diminished. The quantity of urinary pigment is considerably increased in all acute febrile diseases in spite of the fact that, at the same time, there is a diminution in the amount of urine ; it usually reaches 16, 20, and more. This increase in the urinary pigment is still greater in fevers which are accompanied by dissolution of the blood (typhoid, septic fevers). We observe as a general consequence of all of these diseases * According to some of my investigations the quantity of coloring matter whicli is passed with, the stools is very variable. I found during twenty-four hours from 8 to 30 parts of coloring matter measured according to the above scale. f Some observations on the urinary and alvine excretions, as they appear with- in the tropics, British Rev., Oct. 1861, p. 483, et seq. Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 465 a diminution of the number of blood corpuscles, a more or less anaemic condition of the body (more exactly oligocytlisemia). Examples. In a large number of patients witli pneumonia the daily quantity of urinary pigment varied between 16 and 24 units during the height of the disease. In a case of acute rheumatism it amounted to between 30 and 32 when the disease was at its height ; in a man suffering from typhoid it amounted during several days to between 80 and 100 ; in a man who had inhaled arseniuretted hydrogen, from 600 to 800. In the last case the matter which colored the urine differed somewhat from the ordinary urinary pigment, as it was nearly pure hsematin, so that its determination quantitatively, according to the inten- sity of the color, could only be approximate; the difference, however, between the quantity found in these cases and the normal quantity is so very great, that an error in the estimation of one-quarter or even of one-third need scarcely to be taken into account. On the other hand the quantity of urinary pigment in many diseases is decidedly below the normal, in those cases in which a diminished metamorphosis of the blood corpuscles must be assumed to exist ; as in many cases of chlorosis and anaemia ; in convalescence from severe diseases ; in hysteria and nervous diseases, etc. In such cases the character of the urine fre- quently serves as an aid in the diagnosis and treatment, since tonics, especially preparations of iron, are usually indicated. Examples. The daily quantity of urinary pigment in chlorotic persons is frequently below 1 ; in convalescence from severe diseases it is often for a long time not above 1 or 2, etc. II. QUANTITATIVE ALTERATIONS OF THE URINE WHICH REQUIRE A COMPLICATED CHEMICAL ANALYSIS FOR THEIR DEMONSTRATION. §128. The quantitative alterations of the urine considered in the previous sections are very easily determined, and their estima- tion requires so little practice and special knowledge, so little apparatus and accessories, that, in point of fact, it is not too much to ask that every physician should undertake the investi- 30 Digitized by Microsoft® 466 SEMIOLOGT OF HUMAN URINE. gation of them himself, in those cases where it is of importance to determine these changes of the metamorphosis and to draw- conclusions from them. The quantitative alterations in the composition of the urine which are to be spoken of now, have been hitherto much more difficult to determine; for the most part they required much time, more in fact than the busy practitioner could give to them, and presupposed special chemical knowledge and a certain practice in quantitative chemical analysis, be- sides requiring manifold apparatus, utensils, and reagents. Many of them, indeed, could be carried out with the requisite certainty only in a completely furnished laboratory, which is rarely at the command of a physician. Consequently, ana- lyses of this kind have hitherto been undertaken almost solely by chemists for the solution of physiological questions, and rarely by physicians for practical purposes. Moreover, the report of such investigations has been regarded by most practitioners as no essential contribution, nor as a necessary part of the history of the disease in question, but as a super- fluous embellishment ; indeed, by many it is regarded as quite an unnecessary extravagance. Under these circumstances it w^as useless to expect physicians to undertake such investiga- tions. Only a few voluntarily applied themselves to it, partly through love of science, and partly because they were con- vinced that, by undertaking them in some cases of disease en- trusted to them, they might render important service. Happily this state of things has essentially changed in the last few years. Jointly with the ever-increasing application of chemistry to the arts and manufactures grew the discovery of methods which essentially simplified and shortened quantita- tive chemical analyses. These methods, especially the so-called volumetric methods, are very well adapted to the purposes of the physician. This applies especially to the quantitative ex- amination of urine. These simple methods of quantitative analysis are already completely worked out for many of the constituents of the urine, and we may hope that they will be speedily extended to the rest. In short, most of the quantita- tive examinations of urine, which a few years ago were difficult to perform, are now so simplified that they exceed neither the knowledge, skill, nor expedients which we may expect a physi- Digitized by Microsoft® QUANTITATIVE CHANGES IN TEE URINE. 467 cian to possess. Even want of time can no longer serve as an excuse for a physician for neglecting sucli investigations in cases, where they are necessary, since a chemist or an apothe- cary can be found almost anywhere, who, for a small sum, will undertake the simplified analysis for the physician; and, in case of need, any apt attendant on the sick, or servant, if he be careful and intelligent, may be taught in a short time enough for the purpose. In many cases, indeed, the patients them- selves are not only inclined, but are also qualified to undertake such investigations. The chief point for the physician who undertakes such ana- lyses, or causes them to be undertaken, is that he should always clearly know, as far as possible in each case, what he wishes and may expect to ascertain by the examination. Any one who is not quite clear on this point would do better to give up such investigations entirely, since, in such a case, the analysis is generally useless and often even mischievous. The chief "ob- ject which has been in my mind in the following sections has been to instruct the physician upon these points, as far as it is possible to do so at the present time. I must first, however, before considering the special investi- gations of the individual constituents of the urine, premise cer- tain general rules which are more or less applicable to all such quantitative examinations. They form the contents of the next section. § 124 Geneeal Eules foe Quantitative Analysis of the Ueine. 1. Hitherto observers have usually made use of an indefinite quantity of urine for quantitative estimations, and have been satisfied when they had ascertained how much urea, uric acid, chloride of sodium, etc., etc., was contained in 1,000 parts. And at the present time, also, such analyses of the urine are quite often sent or brought to me by patients who come to consult me about themselves. From such an analysis, however, we learn nothing more than the relation which the single constitu- ents of the urine bear to each other. It is, therefore, rarely of much service to the physician. And if such a quantitative analysis only includes a single constituent of the urine, so that we only learn from it how much urea, or uric acid, etc., 1,000 Digitized by Microsoft® 468 SEMIOLOGY OF BUMAN UBINE. parts of the urine contain, it is wholly useless. A quantitative analysis of the urine gives a measure of the metamorphosis only when, together with the relative quantities of the various constituents of the urine, the time is also given during which they were passed ; so that we must not only learn how much urea, uric acid, etc., are contained in 1,000 parts of urine, but we must also know what quantity was passed in a certain time, as in twenty-four hours, one hour, etc. Hence, the first requi- site in every quantitative analysis of the urine is the determina- tion of the time during which it has been passed. This deter- mination is very easy in certain patients. Either the urine of one day (twenty-four hours) is collected, when it rarely hinges on a quarter of an hour, more or less, or the patient carefully observes the quantity of urine secreted during a shorter inter- val. If, for example, the patient passed his urine at eight o'clock and it was not preserved, and at ten o'clock he passed a fresh quantity which was measured and subjected to quantitative analysis, we know that the whole amount of the different con- stituents of the urine found by the examination were derived from a two hours' secretion, and from it we can easily calculate how much urea, uric acid, chloride of sodium, etc., were passed in one hour, or in any given time. The determination of the quantity of the urine, and the time during which it was passed, therefore, forms the basis of all quantitative urinary analyses, and we cannot recommend the physician too strongly to pay the greatest care and attention to these fundamental determina- tions, because, if they are inaccurate, all attention and pains which have been expended on the analysis have been thrown away. The determination of the quantity of the urine passed in a given time is difficult and uncertain in many cases, espe- cially in the sick ; sometimes the time cannot be accurately as- certained, more commonly an uncertain quantity of urine is lost by being passed at stool, or involuntarily when the patient is seriously ill ; often some is thrown away by the fault of the at- tendants or nurse while the physician is absent. The physician must know and guard against all of these sources of error, and in cases where he is not certain that they can be avoided, it is better to dispense with a quantitative analysis of the urine alto- gether rather than to run the risk of arriving at erroneous con- clusions by starting with false premises. Digitized by Microsoft® QUANTITATIVE CHANGES IN THE UBINE. 469 2. It is very important, moreover, that the physician should know the limits of error of the diflferent methods which he makes use of in the analysis, and should always bear them in mind when drawing his conclusions. I will give these limits of error, as far as it is possible at present, in each individual case, but do not consider it superfluous to make a few general remarks on the subject here. The limit of error in an analytical method, that is, the quan- tity by which the result thus obtained may diBfer from the truth, depends on two circumstances : 1. On the accuracy of the method itself ; 2. On the greater or less skill and care of the analyst himself, the completeness of his apparatus, purity of his reagents, etc. The first is unavoidable, but may be deter- mined with tolerable accuracy, and its amount shows the greater or less utility of an analytical method. The second circumstance is variable ; when the analysis is bad the error is great, when it is good it is very small indeed. We cannot expect of every physician who performs a quantitative analysis of urine that he shall be an expert analyst, but we may require him to have an approximate idea of the reliability of his analysis. Any one can readily ascertain this by repeating a quantitative estimation of the same constituent of urine several times with the same ma- terials and following the same method. The greater or less degree of conformity which the different analyses exhibit, gives an idea at the same time of the reliability of the method em- ployed and of the accuracy of the analyst ; it shows how far the figures he finds are to be relied upon, and to what extent his conclusions are to be accepted. If, in this way, by repeated experiment, we have once fixed the limit of error which can be committed in an analysis, we may, in cases in which great ac- curacy is not necessary, content ourselves with a single uncon- trolled analysis. In all quantitative analyses, however, where great accuracy is required,, where the material admits of a repe- tition of the analysis, a second analysis to control the first is always to be made, and if the results differ very much, still a third, and the average of the results is then to be taken. Frequently cases occur where an accurate determination of the quantity of constituents of the urine is not necessary for practical purposes ; where, in fact, it is quite enough to know that a specimen of urine contains more or less than a cer- Digitized by Microsoft® 470 BEMIOLOar OF HUMAN UBINE. tain amount of any constituent. A few examples will illus- trate this. A healthy man passes about 10 to 13 grm. of chlo- ride of sodium with his urine in twenty-four hours. In most acute diseases during their height the separation of the chlo- ride of sodium by the kidneys is reduced to a minimum. If, therefore, we learn by an approximate analysis (which will be explained later) that less than 1 grm. of chloride of sodium is passed with the urine in twenty-four hours, we may conclude that there is a very considerable diminution in the separation of chloride of sodium : in many cases this is quite sufficient for the purposes of the physician, and it is of no importance to know whether the quantity of chloride of sodium amounts to O'l or 0"5 or 0'8 grm. A healthy man passes in an hour about 0'070 to 0*100 grm. of sulphuric acid with the urine. If we find by a simple experiment that a person passes more than 0'400 grm. in an hour, we can conclude that the separation of sulphu- ric acid is very much increased, and that the quantity amounts to at least four times the normal standard. Such approximate determinations, which may be variously modified according to circumstances, have the great advantage to the physician that they can be conducted in a very short time, within two or three minutes, while an accurate estimation would require perhaps thirty or forty minutes. However, we must draw no further conclusions than those which the results warrant. It appears from this that the quantitative analysis of urine may and must be carried out in very different ways according to our object. A physician who knows what he wants may in certain cases draw conclusions from an approximate quantita- tive analysis performed in a minute or two, which are more valuable to him than the results obtained by a careful analysis conducted by a skilled chemist who perhaps has devoted several days to the operation, but which is useless to the physician because just that point which he wanted to know has been omitted. This shows how important it is to keep clearly in mind the object aimed at. 3. The question as to the significance to the physician of the increase or diminution of this or that constituent of the urine will be answered under the head of each constituent. It appears advisable to me, however, to premise here a few Digitized by Microsoft® QUANTITATIVE ORANGES IN TEE UBINE. 471 general remarks which are equally applicable to several con- stituents. , The different constituents of urine may be divided iato two great classes, according to their origin. Those of the one class are doubtless formed within the body ; they are in fact the products of the activity of the body. Urea and uric acid, which are very rarely taken into the body as in- gesta, belong here. A diminished quantity of these bodies in the urine always shows that they have either been produced in less quantity than normal, or that they are stored up and re- tained in the economy ; perhaps also in a few rare cases they have been eliminated in an abnormal way, or have undergone a partial decomposition and transformation within the system. On the other hand, their increased secretion with the urine shows that they are either produced in larger quantity than normal, or that they have been stored up somewhere in the body and have all at once been eliminated. Most of the constituents of the urine belong to the second class ; they may be produced within the system in part, or be formed from other matters by chemical decomposition ; some of them only go through the body, however, and whether greater or less quantities of them are passed with the urine depends in part on the varying activity of the body, and in part also on whether greater or less quantities of them are taken into the body with food, drink, medicine, etc. Thus, for ex- ample, the oxalic acid of the urine, as described in § 110, may be formed within the body from other substances, or it may have been taken in with .food containing oxalic acid. The sulphuric acid of the urine may result from the oxidation of the sulphur contained in the protein substances and constitu- ents of the body, or it may come from sulphate of calcium con- tained in drinking water, etc. And whether the urine contains more or less chloride of sodium, may depend upon an increase or a diminution of the action of the kidneys, or upon the ad- dition of a greater or less quantity of salt to the food. When, therefore, an increase or diminution of the constitu- ents of the urine belonging to this class is found, we must be very careful in drawing our conclusions, and must only refer the cause to a change in the activity of the system or to its' pathological conditions, when we» are convinced that the in- Digitized by Microsoft® 472 SEMIOLOQT OF HUMAN UBINB. creased or diminished secretion does not depend upon a greater or less absorption. Sucli a conviction can only be obtained by determining quantitatively, or at least estimating approxi- mately, how much of the compound in question was taken into the body in a given time by the different ingesta. Such investi- gations are very laborious and have hitherto been very rarely undertaken. Therefore, this whole subject is still shrouded in darkness, and the statements which have hitherto been made by different observers concerning the increase or diminution of ■ single constituents of the urine in diseases must be received with a certain amount of caution. Finally, we will allow a place here for an observation which has been omitted in previous editions as unnecessary, because it appears self-evident to every intelligent person, but which perhaps is not superfluous, since experience has taught us that it has often been neglected and still continues to be. When we wish to determine alterations of the urine of a general nature, as, for example, those which are produced by certain influences, certain diseases, etc., very numerous observa- tions are necessary as a basis, if the conclusions drawn from them are to be in a measure exact and of scientific value. Only in those cases in which all of the observations without excep- tion show a very considerable deviation from the normal, and always in the same direction, as, for example, diminution in the quantity of urine in febrile diseases (see page 451), is a mode- rate number of observations sufficient. On the other hand, the less the deviations are from the normal, so that they in part fall within the limits of the necessary errors of observation, and the less these deviations follow each other in the same direction but appear sometimes positive and sometimes nega- tive, the greater must be the number of observations instituted; and in very complicated cases, in which at the same time many influences of different sorts act on the urinary secretion, some- times thousands of examinations do not suffice to establish a "law." Any one, who, heedless of this precaution, inconsiderately draws conclusions from a few investigations whose results are very easily influenced by accidental circumstances, does not con- tribute to science, but rather brings confusion into it, and has himself to thank when he reoeives a well-merited rebuke. Digitized by Microsoft® QUANTITATIVE CRANGMS IN TEM UBINE. 473 We now turn to the special consideration of the indications presented by the increase or diminution of the different con- stituents of the urine. § 125. Ueea.* The mode of determining the quantity of urea in the urine and the modifications of the process necessary in certain cases have been already described fully in § 65 ; it remains for us here only to consider the accuracy and limits of error of this method, as well as the information which may be obtained from the results. It seems to be very uncertain, and may lead to considerable error, to calculate the quantity of urea in a specimen of urine from its specific gravity according to certain formulas as re- commended by some authors, for example, Haughton. (See page 455.) I. The estimation by Liebig's method is certainly the most convenient, and, therefore, is to be recommended, especially for the purposes of the physician. It is very accurate, so that comparative analyses undertaken with the same urine, and very carefully performed, gave a difference of less than one per cent. There are two sources of error, however, in this method of de- termining the quantity of urea, which in certain cases may lead to considerable inaccuracy, and they can only be avoided by quite troublesome and long modifications of the original method. They are as follows : 1. The error which depends on the presence of chloride of sodium in the urine. This, together with the means of avoiding it, have already been pointed out on page 237, et seq. I have, therefore, only a few practical remarks to make on this point. In all cases in which we wish to obtain a very accurate estimation of the quantity of urea in a specimen of urine, where an error of one or two per cent, is not admissible, we must precipitate the chlorine from the urine by nitrate of silver, as described on page 238, et seq., before estimating the urea. In estimations in which so great accuracy is not required. * Th. L. W. BisctofE, Der HamstofE als Maass des StofEweclisels, Giessen, 1853. Voit, Zeitschr. f. Biologie, Band 4, p. 77, et seq. Digitized by Microsoft® 474 SEMIOLOGY OF HUMAlf UBINE. this tedious process may be omitted ; tlien two courses remaia . to us : First, we may take no account luhatever of the chloride of so- dium which is present. We then, except in the cases where there is no chloride of sodium at all, or merely traces of it, always obtain too high a figure for the urea. The error may amount to 10 or even 20 per cent. It will be great, for instance, if we compare the urine of healthy people, which usually con- tains an abundance of salt, or of persons suffering from chronic diseases, with the urine of those who are suffering from acute diseases, which usually contains very little chloride of sodium. Or we may make a correction for the amount of chloride of sodium in the urine in the quantity of urea which has been found. (See page 238.) Such a correction, however, is always merely approximate, and the error may reach as high as five per cent, and be either positive or negative. 2. A second source of error in the Liebig process is that other matters than urea may be precipitated, in which case the weight of the urea obtained will be too high. This is true of allantoin, kreatinin, and sarkosin (see page 241) ; it is also true of other nitrogenous constituents of the urine, which are more frequently present, especially in the urine of the sick. Kletzinsky* found in a number of carefully performed experiments that a nitrogenous compound, which was not urea, was precipitated by an acetate of lead solution from most urine, but in Liebig's method was precipitated with the urea and is included with it in the calculation. The quan- tity of this substance in the experiments of K. amounted to 4, 3, 3, 2, and 2 per cent, in healthy urine ; in the urine of sick people, on the other hand, it was much greater (amounting to about 12 per cent.). Hence too high a number for the urea, especially in the urine of the sick, may be found, and this error, in many cases, can probably reach as high as 20 per cent. This error is often, to a certain extent, counterbalanced, since the urine in acute diseases may contain very little chloride of so- dium, and, therefore, the amount of urea found in it, compared with that found in the urine of persons in health, without cor- * See Kletzinsky, Komparative Versuche iiber den Werth verschiedener Me- ttoden der Harnstofibestimmung, Heller's Aichiv, 1853, p. 253. Digitized by Microsoft® QUANTITATIVE GHANGE8 IN THE UEINE. 475 reotion for the chloride of sodium, would be too small ; but such compensations suffice only in very superficial investigations, and are not reliable when absolute accuracy is required. To avoid this error, we must add to the urine under examina- tion sugar of lead solution, rendered acid by a <^op or two of acetic acid, until the whole of the substances capable of pre- cipitation are separated ; then any excess of lead is precipitated from the filtrate by sulphuretted hydrogen and the urea deter- mined by Liebig's method. II. What conclusions are to be drawn from an increase or diminution in the quantity of urea in the urine ? Naturally the quantity of urea which is separated under nor- mal conditions by people in health, forms the basis of such conclusions. Numerous investigations, carried on by different persons, have shown that a well-nourished, healthy, adult man passes, on an average, from 25 to 40 grms. of urea in twenty- four hours, and from I'O to 1"66 grm. of urea in one hour. Thus, calculating for the weight of the body, it follows that from 0"37 to 0"60 grm. are passed, on the average, in twenty- four hours, and from 0-015 to 0-035 grm. are passed in one hour for every kilogram of weight of the body. The absolute quantity of urea passed by women, and, of course, also by children, is somewhat less. On the other hand, the rdative quantity of urea passed by the latter, in proportion to the weight of the body, is greater than in adults. According to the computations of IJhle,* children pass in twenty-four hours, for each kilogram of weight : Children from 3 to 6 years of age, about 1-0 grm. of urea. ce ei g li 11 II a ti " 0-8 " " " " " 13 " 16 " " " " 0-4 or 0-6 grm. of urea. These normal averages are naturally somewhat variable in different people, and also in the same person at different times, according to the bodily constitution, variety of diet, and greater or less activity of metamorphosis. Moreover, they do not in- clude the maximum and minimum quantities of urea in certain cases in perfectly healthy individuals. Food, especially, has a decided and very great influence on * Wiener medic. Wochenschr., 1859, 7 to 9. Digitized by Microsoft® 476 SEMIOLOar OF HUMAN UBINE. the quantity of urea excreted. More urea is passed -with a purely animal diet than with a mixed diet ; and more with a mixed than with a Tegetable diet ; least of all is passed during complete abstinence from food. The observations of O. von Franque * give a very intelligible idea of the degree of this influence. He passed in twenty-four hours : With a purely animal diet, 51 to 92 grm. of urea. " " mixed " 36 " 38 " " " " " vegetable " 24 " 28 " " " " "■ non-nitrogenous " 16 " " " The importance which urea has for the physiologist and phy- sician is that it forms an approximate measure of the meta- morphosis of the protein compounds which exist in the body, and thus we find the quantity, not of the whole metamorphosis, but at least of a very important part of it. Although the urea of the body comes originally from the protein substances, yet it does not spring directly from them. Various intermediate bodies are first formed by the metamor- phosis, some of which yield urea more readily than others. (See page 4) In certain processes of the metamorphosis, espe- cially pathological ones, other substances instead of urea, as leucin and tyrosin, are formed. (See § 133.) "Whatever increases the metamorphosis of the protein sub- stances, as a rule, increases the urea, and vice, versa; therefore, the production of urea is in general rather greater during the waking hours than during sleep ; it is increased by a rich, largely animal diet, and diminished by a sparing, or largely vegetable diet ; it increases and diminishes with the degree of activity of the body and the mind. Therefore, the quantity of urea may be increased or diminished in perfectly healthy indi- viduals by a variety of influences, which we will not consider any further here. The quantity of urea passed with the urine in a given time does not depend alone upon the amount of urea produced, but also upon whether the urea formed in the body is completely * Beitrage zur Kentniss der Harnstofiaussclieidung beim Menschen, Inaug. Abhaudl., Wurzburg, 1855. Digitized by Microsoft® QUANTITATIVE GHAJSfGES IN THE URINE. 477 separated- or partially retained in the blood and parenchyma- tous fluids. Hence, the quantity of urea increases tempora- rily with the increase of the urinary secretion, and diminishes when it lessens. The quantity of urea in disease depends on similar conditions. A long-continued increase of the urea in the sick, always in- dicates increased conversion of the nitrogenous elements. A temporary increase of the urea, however, may depend on an in- crease of the urinary secretion, by which the urea collected in the body is quickly passed off, and does not necessarily indi- cate an increased production of urea. A diminution of the quantity of urea may depend on : a. A diminution of the protein metamorphosis. b. A retention of the urea in the body (as in uraemia and dropsy). The secretion of urea in all acute febrile diseases (pneumonia, typhoid fever, etc.) has naturally the following course : At the commencement of the attack, and until the acme of the fever has been reached, the quantity of urea is generally increased, sometimes up to 50, 60, and even 80 grm. in twenty- four hours, and this in spite of a simultaneous low diet, and accompanying diminution of the quantity of urine. This in- crease of the urea, however, does not always keep pace with the increase of the bodily temperature. Later, when the fever diminishes and the increase of meta- morphosis has ceased, and while the continued disturbance of the appetite causes a diminished ingestion of food, the quantity of urea sinks below the normal. During convalescence the quantity of urea gradually returns again to normal. This regular course is naturally variously modified by indi- vidual circumstances. In intermittent fevers the excretion of urea is markedly in- creased during the paroxysm of fever. This increase commences before the occurrence of the cold stage, which is important with respect to the theory of the fever. In most chronic diseases, which are accompanied by a dimi- nution of the tissue metamorphosis or of the nutrition, the quantity of urea sinks below the normal. During intercurrent exacerbations, hectic fever, etc., it is increased again. Digitized by Microsoft® 478 SEMIOLOGY OF HUMAN URINE. The quantity is the least when diminished metamorphosis occurs at the same time with diminished action of the kidneys. For this reason, toward the fatal termination of many diseases, it is frequently very small (5 or 6 grm. daily). In dropsical conditions it is frequently very much diminished, a portion of the urea being dissolved in the dropsical fluids and thus retained in the body. When, on the other hand, the se- cretion of urine is rendered abundant in such patients by the action of diuretics, or by a spontaneously increased activity of the kidneys, the secretion of urea will sometimes be considera- bly increased for a time, and then much more urea will be passed than is produced at the time. The excess of the excre- tion over the production arises from the supply stored up in the body. If for a long time much less urea than normal is passed with the urine, we have reason to fear that ursemia may result from the retention of urea in the blood. Yet those cases are to be judged differently in which the urea is diminished in the urine or even wholly absent, because leucin and tyrosin are formed in its place, as in acute atrophy of the liver. (See § 133.) Urine which contains a large quantity of carbonate of ammo- nium, which results from the decomposition of the urea, natu- rally contains relatively less urea than normal ; the amount of urea, therefore, in strongly ammoniacal urine is no sure criterion of the quantity of urea produced. The method which must be followed in such cases in order to determine the urea is given on page 240. The following examples will serve as explanations and proofs of the conditions given above : A. In health. A large number of estimations of urea, made according to Liebig's method, without correcting for the chloride of sodium, gave the following figures for strong, healthy men on good diet : 1. In H., average quantity of urea per hour, . . . . 2-13 grm. 2. " M., " " <<<<<<<. .... 1-47 " 3. " J., " " " " " " 1st series of experi- ) . „„ „ ments, summer, 1853, J i- " J-, " " " " " " 3d series of experi- ) ^.^r „ meats, Oct., 1853, f -^ o" The numbers given under 2 to 4 are the averages of a large Digitized by Microsoft® QUANTITATIVE ORANGES IN TEE URINE. 479 number (far more than a hundred) of observations ; consequent- ly they represent pretty accurately the average production of urea in the individuals referred to at the time the experiments were conducted ; they are all, however, somewhat too high (pro- bably about 10 per cent.), because the chloride of sodium was not precipitated from the urine. On account of the large number of the above single observa- tions they may also serve to indicate the amount of urea pro- duced at different times of the day. The hourly quantity of urea amounted to : Morning. Afternoon. Night. In M., . 1-7 1-58 1-2 " J., 1853, 1-68 1-71 1-61 " " 1853, . 2-12 1-82 1-73 From this it appears that the amount of urea produced at dififerent times of the day does not show much variation ; only during the night it was a little less than during the day in every series of experiments. Observations on the same individual at different times of the year (in J., in summer, 1852, and in Octo- ber, 1853) likewise show a tolerably great uniformity. To give an idea of the amount of the variations which the hourly secretion of urea in healthy persons may present, I will give the maximum and minimum of the hourly excretion of urea in each of the above series of experiments : 1 3 4 B. In disease. In Typhoid Fefoer. During the height of the disease the daily quantity of urea varied between 40 and 55 grm. As the fever diminished, it gradually fell to 20 grm., and during convales- cence gradually rose again to the normal. In a case of typhoid which terminated fatally, the quantity of urea during the height of the fever amounted to 35, 40, and 50 grm ; it fell gradually as the disease approached a fatal issue to 25, 20, 10, and during the last twenty-four hours before death amounted to only 5 grm. In Pneunumia. During the height of the fever the quantity Digitized by Microsoft® iximum. Minimum. 3-13 1-54 2-45 0-88 3-41 1-05 2-82 0-89 480 8EMI0L0&T OF HUMAN URINE. of urea increased to 50, 60, and even 70 grm., falling as the fever diminislied to 25 and 20, and rising again during convales- cence. In a case of disease of the heart with dropsy the daily quan- tity of urea was for some time below the normal, 20, 25, and 28 grm. As the amount of urine was increased by diuretics, the quantity of urea also daily increased to 50 or 60 grm., but it fell again as the diuresis ceased. This state of things was several times repeated. In a patient with rigid arteries and emphysema of the lungs, and who also suffered from an intercurrent attack of acute bronchitis with oedema of the lungs, the quantity of urea was generally small, below 30 grm. With the occurrence of urse- mic symptoms the quantity fell to 12 and even 10 grm. ; under the influence of diuretics it temporarily rose again to 25. Then came a new collapse with simultaneous diminution of the quan- tity of the urine and of the urea (to 11 grm.), and death. During the last few years a large number of investigations respecting the quantity of urea secreted in different diseases have been published. They confirm in all main particulars the above general statements already published by me ; which statements were based on very numerous observations made by me in the clinic at Giessen, in part before the publication of Liebig's method, at the instigation and with the assistance of my revered friend. A closer study here of' the relation of the secretion of urea to particular diseases would lead us too far ; that belongs to special pathology.* * Those who wish, to pursue the subject further will And the most important literature as follows : Alfred Vogel (Henle and Pfeuffer Zeitschr., N. P. iv. 3). S. Moss (ibid. vii. 3). W, Brattler, Ein Beitrag zur Urologie, Milnchen, Palm, 1858. (All of these three works treat of the secretion of urea in dif- ferent diseases.) W. Mliller iiber HarnstofEabsonderung, etc., nach operativen BingrifEen (Wiss. Mittheil. d. Erlanger physik, med. Societat, 1858, Heft 1). E. Sander, HarnstofEausscheidung bei paralyt. Blodsinn (Virchow's Archiv, 1858, p. 100). P. S. Warnete, HarnstofEausscheidung im Typhoid (Bibl. for Laeger, xii. , p. 330). Desgl. im Wechselfieber ; Traube und Jochmann (Deutsche Klinik, 1855, Nro. 46). Sidney Ringer (Med. chirurg. transact., 1859, p. 360, et seq., Desgl. in der Cholera ; Fr. Lehraann (Inaug. Diss., Zilrich, 1857). Trajibe (Berl. klin. Wochensclir. , 1864, 17), Ueber vermehrte HamstofEpro- duction in fieberhaften Krankheiten. E. Unruh (Virchow's Archiv, 1869, 48, p. 227, et seq)., Ueber die StickstofEausscheidung bei fieberhaften Krankheiten. Digitized by Microsoft® QUANTITATIVE CHANQES IN THE UBINE. 481 § 126. Ubic Aom.* The quantitative estimation of uric acid is to be made ac- cording to the method described in § 73. In all cases in which the urine contains a sediment of uric acid or urates — and it is just in these cases that the quantitative estimation of uric acid has the most interest for the physician — we must naturally either employ the whole quantity of the urine in its estima- tion (in case it should not succeed the sediment is to be dissolved again completely by heat), or the urine must be filtered and the precipitated uric acid which remains on the filter, as well as that in solution in an aliquot part of the fil- trate, must be determined, and then the whole quantity of uric acid contained in the urine calculated from these two together. But such an exact quantitative estimation of the uric acid is tolerably tedious and troublesome, and will rarely be undertaken, therefore, practically by physicians, who will usually content themselves with judging from the presence of a sediment of uric acid or urates in the urine how much the quantity of uric acid in it exceeds the normal amount. Such a conclusion, however, is not reliable ; a sediment of urates fre- quently occurs without the quantity of separated uric acid ap- pearing absolutely (that is, in a given time) increased. (See §107.) When we have determined the quantity of uric acid in the urine, the next thing naturally is to ascertain whether the quantity found is normal, or greater or less than normal. For this purpose it is necessary to know the average daily or hourly quantity of uric acid secreted by healthy people. Numerous investigations, especially by Lehmann, Neubauer, and chiefly by Eanke, have furnished tolerably accurate information on this point. *H. Ranke, Beob. und Versuche iiber die Ausscheidung der Harnsaure beim Menschen, etc., Milnchen, Kaiser, 1858. B. J. Stokvis, Bijdragen tot de pliysiol. van bet acid, uricum, Ned. Tjidscbr., 1859 (Schmidt's Jabrb., Bd. 109, p. 3). Zabelin, Ueber die Umwandlung der Harnsaure im Tbierkorper, Annal. d. Cbem. u. Pbarm., 1863, Suppl. ii., p. 336, et seq. Bartels Untersucbungen iiber die Ursaohen einer gesteigerten Harnsaureausscbeidung in Krankbeiten (Deutsobes Arcbiv f. klin. Med.,i., p. 13, et seq.). B. Naunyn u. L. Eeiss, Ueber Harnsaureausscbeidung (Reicbert's u. DuBois-Raymond's Arcbiv, 1869, ' Heft 3). 31 Digitized by Microsoft® 482 BEMIOLOOT OF EUMAN TTBINB. According to these observers the average quantity of uric acid which an adult individual (male as well as female) passes with the urine in twenty-four hours is from 0"3 to O'S grm. This average quantity, however, differs considerably in differ- ent individuals. Also in the same person at different times variations occur, which in many individuals are very consider- able, in others less. The nature of the food appears to exercise the chief influence over the quantity of the uric acid excreted. During fasting the quantity is diminished very much, it increases rapidly after eating, and almost as much after taking non-nitrogenous as ani- mal food. (Eanke, W. Eoberts.) The relation of the quantity of uric acid to that of urea varies considerably (from 1 : 27 to 1 : 80, and indeed in a few cases from 1 : 300 and even more). Lehmann passed an average of 1*18 grm. of uric acid in twenty-four hours, but considered that this was an abnormal amount. According to Becquerel the daily average quantity amounts io 0-49 and 0-56 grm. Neubauer found in a large number of observations on two bealthy persons, that in one the average was 0'28, the maxi- mum 0"61, the minimum 0'002. In the second the average for twenty-four hours was 0*49, the maximum = 0"67, minimum = 0-33. Kanke, who has made numerous investigations, obtained as average numbers for twenty-four hours, in a long series of ob- servations on himself, average 0'648, maximum 0-875, minimum 0-445. In other men, 0-225— 0-654^0-556— 0-78— average =0-707, etc. In two women, the quantity in one was from 0-410 to 0-456, average = 0-429. In the second, from 0-458 to 0-565. Regarding the effect of sickness, Ranke found that in inter- mittent fever an increased amount of uric acid was excreted during the attack. He found, moreover, that the uric acid was decidedly increased in leukaemia, a fact which was also observed by others ; that it was sometimes diminished in diabetes melli- tus, and (as shown by Garrod and Neubauer) always markedly diminished in chronic gout (where, according to Garrod, it is stored up in the blood). Large doses of sulphate of quinine, according to Eanke, diminished the excretion of uric acid. Digitized by Microsoft® QUANTITATIVE CHANGES IN THE UBINE. 483 Bartels found a decided increase of the uric acid, especially in proportion to tlie urea, in all of tliose febrile diseases whicli are accompanied with marked disturbances of the respiratory pro- cesses, and he therefore concludes that such an increase is the result of a relative respiratory insuflSciency, that is,- of an in- complete oxidation. The causes and indications of an increase or diminution of the uric acid are, therefore, still somewhat obscure and hypo- thetical. Uric acid, like urea, is a product of the body, and in fact of the metamorphosis of the nitrogenous constituents. In so far it has the same indication as urea. But uric acid stands a step higher on the ladder of retrograde metamorphosis than urea; the latter may be formed from uric acid by oxidation. Therefore uric acid is often regarded as imperfectly oxidized urea, and it has been thought that the increase of the uric acid has always occurred at the expense of the urea, wherever, through the imperfect supply of oxygen, the decomposed nitro- genous elements of the body are incompletely oxidized before their removal from the system, and consequently in all diseases which are accompanied by disturbances of the respiration. This opinion, however, does not agree with the fact that per- fectly healthy people also always pass a certain quantity of uric acid. Moreover, we find in those diseases in which an in- crease of the uric acid is most constantly observed — at the height of febrile diseases — that the excretion of urea is always increased as well as the uric acid. Uric acid, therefore, is surely something more than imperfect urea; but we must wait for future investigations to form further conclusions as to the true source of its formation and its actual significance in the econ- omy. Since the phenomena which occur in animals may serve to extend our knowledge of these relations, it is worthy of mention that in carnivora confined in cages and whose freedom to move about at will is, therefore, removed, the uric acid in the urine is increased. In herbivora uric acid is not found at all, but it appears in their urine when they are fasting, that is, when they live on their own flesh. We have already spoken of the significance to the physician of uric acid deposited as a sediment within the body in § 107. Digitized by Microsoft® 484 SEMIOLOGY OF HUMAN UBINE. § 127. Free Acids* The quantitative estimation of the free acids in the urine is easily and quickly made according to the method given in § 68. Only it must be commenced as soon as possible after the urine is passed, since the quantity of the free acids is readily changed by the occurrence of the acid or alkaline fermentation of the urine. According to F. Soxhlet.t however, the titration of the degree of acidity of the urine by means of a solution of sodic hydrate yields a result which is accurate only within tolerably broad limits, since there is no soluble phosphate which has a neutral reaction, and since in titrating a point always occurs in which both acid and alkaline reactions are present at the same time. Still, these limits of error are not so broad as to set aside the usefulness of such analyses, especially for practical purposes, when we content ourselves with only drawing conclusions from them which are not impaired by those unavoidable errors. (See § 124.) Numerous observations of this kind which I conducted partly myself and partly had carried on under my guidance showed that a healthy man passed on an average daily about 2 or 4 grm. of acids with the urine, and in an hour about 0-10 to 0*20 grm. (calculated as oxalic acid). The hourly quantity varies not in- considerably according to the time of day, and in four different persons on whom investigations were made it was uniformly greatest at night, least in the forenoon, and between the two during the afternoon. The average hourly amount in the urine of the individual on whom thfe greatest number of investigations were made was in the night 0'19, forenoon 0"13, afternoon 0"15 grm. The quantity of acids in the urine is undoubtedly diminished *Tli. Eylandt, De acidorum sumptor. vi in urinsB acorem. Diss, inaug., Dor- pat, 1854. J. Ch. LehmanD, Bibl. for Laeger xiii., p. 18 (Schmidt's Jahrb., Bd. 108, p. 148). W. Roberts, A contrib. to urology, embracing observations on the diurnal variations in the acidity of urine, chiefly in relation to food, Manchester, 1859. Klilpfel (Hoppe-Seyler, Medio, chem. TJntersuchungen, Heft 3, p. 413, et seq.). A. Savdcky (Pfliiger's Archiv, 1872, v., p. 285, et seq. C. Qaethgens, Zur Prage der Ausscheidung freier Saure durch den Ham (Cen- tralbl. f. d. medic. Wissensch., 1872, p. 833, et seq.). f Journ. f. pratt, Chemie, 1873, vi. Digitized by Microsoft® QUANTITATIVE CHANGES IN THE UBINE. 485 by the use of caustic alkalies, carbonates or organic salts of tlie alkalies, indeed tbey may entirely disappear after large doses of these compounds and the acid reaction of the urine become alkaline, as in the formation of carbonate of ammonium by de- composition of the urea, as has been repeatedly mentioned. ' On the other hand, the acidity of the urine is increased by the internal exhibition of the mineral acids. Example. In a young man who had taken large quantities of mineral acids (SO3 and CIH) for a long time on account of severe haemoptysis, the daily average quantity of acid in the urine amounted to 5"4 grm. (an average of six days), and in- creased on one day to 7'5 grm. Gaethgens found also in dogs into whose stomachs he injected dilute SO3, that the free acids of the urine were essentially increased thereby (from 13 to 72). The very numerous and careful observations made by W. Eoberts confirm the statements of B. Jones (see page 375, a) that during a period of time, from one to three hours after a meal, the secretion of acid by the urine diminishes both abso- lutely and in relation to the solid constituents of the urine. Not unfrequently, indeed, the urine at this time becomes tem- porarily alkaline. Mixed, purely vegetable, and purely animal diets have the same action. Eoberts ascribes this result of taking food, as does also B. Jones, not to the secretion of acid gastric juice, but rather to the passage of alkaline salts, or of those which will become alkaline, from the food into the blood. The greater or less amount of acid passed with the urine de- pends probably not only on the greater or less quantity taken, but also doubtless upon internal changes of metamorphosis, as already indicated in § 96, but not yet proved with certainty. According to Klupfel, the free acid of the urine is very much increased by great muscular activity. Sawioky, however, was unable to confirm Kliipfel's statements. According to his ex- perience, the quantity and quality of the food had more influ- ence on the degree of acidity of the urine than rest or work. Numerous estimations of the quantity of acid in sick people have shown that in most diseases, acute as well as chronic, the acid is diminished and almost never increased, except in those cases in which large quantities of mineral acids have been taken. Tet we find during the height of febrile diseases, espe- cially in pneumonia, acute rheumatism, etc., that the percentage Digitized by Microsoft® 486 BEMIOLOGY OF HJJMAN URINE. of free acid in the urine is not rarely increased, so tliat it ap- pears more acid than in health ; this evidently depends on the diminished quantity of the urine in such cases and its conse- quent greater concentration. The diminution of the quantity of acid in the urine of the sick doubtless chiefly depends on the diminished ingestion of food ; perhaps, also, it is due in part to a diminution of the muscular metamorphosis in the sick (see page 376, b). The inrestigations which have been made thus far, do not allow of more special conclusions. Examples — Male : In a patient with pneumonia, the quantity of acid gradually increased from to 1"50. The average of eight days amounted to 0-5. In another patient with pneumonia, who died, the daily quan- tity varied between 0'9 and 3'0. The average of four days was 1'9. In a case of gastric fever, the quantity varied between 0"6 and 1*6. The average of four days was I'l. In a case of acute rheumatism, the quantity for several days was 0"7 and 1. In a case of chronic bronchial catarrh, the quantity varied during eleven days between and 0*8. Average = 0"5. Female: ■ In a girl with scrofulous glandular swellings it was from 1'6 to 2 '4. The average of four days was 2'0. In a woman thirty years of age, suffering from spinal irrita- tion, from to 0"8. Average of five days = 0"7. In a woman seventy years old, suffering from ascites, the result of hepatic disease, from to 3'1. Average of eighteen days = 1-41, etc. § 128. Ammonia.* The methods of determining quantitatively the ammonia con- tained in the urine have been already described in § 77 and § 78. *C. Neubauer, Journ. f. prakt. Chemie, Ixiv., p. 177 and 378. W. Heintz and H. Bamberger, Wiirzburger medic. Wochensclir., Bd. 2, Heft 2 and 3. L. Thiry, Zeitschr. f. rat. Medic, 1863, p. 166, et seg. A. Duchek, Wochenbl. d. Zeitschr. d. k. k. Gesellsch. d. Aerzte zu Wien., 1864, Nr. 51. R. Koppe, Ueber Ammoniakausscheidung durch. die Nieren (Petersburger med. Zeitschr. xiv. 2, 1868). Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 487 It appears from the inTestigations of Boussaingault, Heintz, and Neubauer, that human urine always contains a small quan- tity of ammonia. According to many experiments made by Neu- bauer on different individuals, the average quantity passed by healthy adult males in twenty-four hours was about 0-7 grm. ; the quantity, however, may fall to O'S, and rise to over 1 gram. Koppe also found in normal urine from 042 to 0"45 of ammonia per thousand parts; in women somewhat less. The absolute quantity in men amounted to 0*8 grm. ; in women, to only 0"5 or 0'6 grm., in twenty-four hours. Since only a few experiments have thus far been made on this subject, especially on the urine of sick people, the question as to what importance the increase or diminution of ammonia in the urine has for the physician can at present be answered only very insufficiently and hypothetically. Duchek found ammonia always in the freshly passed urine of patients suffering from various febrile diseases and in not in- considerable quantity, though it did not essentially exceed the quantities given above as observed in the urine of healthy peo- ple. The quantity of ammonia contained in the urine, more- over, appeared to him to increase with the aggravation of the symptoms of the disease, and to decrease as convalescence oc- curred. Koppe found the excretion of ammonia was increased in infectious diseases (I'S to 1-5 grm. in twenty-four hours), and in the florescent stage of typhus, where it is increased with the temperature of the body. The following considerations may serve as a hint, and at the same time as an incentive to further investigations : The ammonia in the urine is evidently derived from two quite different sources : 1. It is derived from the food, from the drink, and from the respired air which contains more or less ammonia. Still, generally speaking, the amount of ammonia in these ingesta is but small, and consequently the quantity removed from the system by the urine is inconsiderable as a rule, less than }j grm. in twenty-four hours. Under certain circumstances an unusually large quantity of ammonia maybe taken into the sys- tem from without in health, as when we remain in an atmo- sphere filled with tobacco smoke, or eat certain food which contains much ammonia, such as radishes, etc.; in the sick. Digitized by Microsoft® 488 SEMIOLOGY OF HUMAN URINE. when preparations of ammonia are given as medicines, such as the carbonate or chloride of ammonium, etc. Neubauer has shown that the greatest part of the chloride of ammonium in- gested is eliminated again by the urine. In all cases in which the daily quantity of ammonia in the urine exceeds 1 grm. the physician should ascertain whether the excess depends upon one or several of these causes. 2. Without doubt ammonia may also be produced within the body by pathological processes. We know with certainty that urea may be decomposed into carbonate of ammonium, and one of the theories of uraemia is founded upon this dangerous pro- cess, that the urea retained in the system undergoes this change into carbonate of ammonium. The facility with which ammo- nia develops from all nitrogenous animal compounds, especially from the blood, the so-called extractive matters, etc., outside of the body, when a slight degree of decomposition has set in, allows us to conclude that in the pathological processes which we call putrid and septic, conditions of decomposition, such a development of ammonia has already taken place within the liv- ing body. Therefore, the detection of an increased separation of ammonia from the system is of great weight in the diagnosis of such conditions of disease (ammonsemia). The ammonia may be separated not only by the urine, but also in other ways, as by the intestine and the lungs, but its quantitative estima- tion in the urine is at present our simplest and surest guide. Great care, however, is necessary in the investigation of aU such cases, since under these circumstances the urea of the urine has a great tendency to decompose (which, as Neubauer has shown, does not happen in normal urine), and it is, there- fore, very difficult to determine how much of the ammonia present in the urine was present when it was first secreted, and how much has been formed by the subsequent decomposition of urea in the bladder or outside of the body. In order to avoid this source of error as much as possible, I would advise in all such cases : 1. To subject the urine to examination as soon as possible after its secretion by the kidneys, by introducing a catheter to draw off all of the urine present in the bladder, and then to subject that which drops from the catheter subsequently to an examination. Digitized by Microsoft® QUANTITATIVE OSAN&ES IN THE URINE. 439 2. To free this urine from coloring matter, extractive matter, mucus, etc, by the addition of acetate and basic acetate of lead solutions, as described on page 308, so as to guard against further decomposition as much as possible. Sometimes the urine contains sulphide of ammonium. Betz considers that in such cases it comes from the intestine, from which it is absorbed into the blood, and there causes danger- ous symptoms of disease (hydrothion-ammonsemia). (See page 143.) The acceptance of this origin, however, requires further proof, since the intestine, even in perfectly healthy persons, very often contains sulphuretted hydrogen without showing any re- sults of the action of this poisonous gas on the blood. § 129. Chloeine and CHLOErDE OF Sodium.* For the methods of estimating the amount of chlorine and common salt in the urine, see § 66. It is immaterial whether the result of the estimation is reck- oned as chlorine or chloride of sodium, although it is certain that in many cases all of the chlorine in the urine is not com- bined with sodium. Therefore care must be taken not to con- found the figures indicating chlorine with those which indicate chloride of sodium, which occasionally has happened, and has led to error, since many writers calculate their results as chlo- rine, and others as chloride of sodium. The starting point for deciding whether the elimination of chlorine with the urine is increased or diminished is the knowl- edge of the average daily elimination of chlorine in health. Hegar has reported a series of very careful examinations of the daily and hourly elimination of chlorine with the urine in seven young healthy men. The average daily amount in the urine varied with the individual, between 74 and 13 '9 grm. There- fore the average daily amount of chlorine passed with the urine by an adult man is about 10 grm. ( = 16'5 grm. NaCl), or hourly about 0*44 grm. 01 (0-73 NaOl). These figures are, however, * Alfr. Hegar, Ueber die Auscheidung der Chlorverbindungen durch den Ham. Giessen, 1852. F. Howitz, Hospitals Meddelelser : andere Eoetke, Bd. 1, p. 64, et seq. ; Schmidt's Jahrb., Bd. 95, p. 283, et acq. E. Ph. Hiokelbein, TJeber den Uebergamg des CSilornatriums in den Harn., Tnaug. Diss., Marburg, 1859. Digitized by Microsoft® 490 SEMIOLOGY OF HUMAN UBINB. probably somewhat too high, since the individuals taken for the examination were mostly students who were strong, ate food with much salt, and drank much. A somewhat lower figure would be more nearly correct for the majority of adults, about 6-8 grm. CI (=10-13 grm. NaCl) daily, and 0-25-0-33 grm. CI (=0-4:l-0-54 grm. JS'aCl) hourly. In women and children the amount of chlorine eliminated is still less. Bischoff found as the mean daily amount of chlorine in the urine of a well-nourished adult man, 8-7 grm., of a woman 43 years old, 5-5 grm., of a girl 18 years old, 4*5 grm., of a boy 16 years old, 5-3 grm., and in that of a boy of 3 years, 0-8 grm. Becquerel found only 0-66 grm. CI in the ignited residue of the daily urine of a healthy person, an estimate, like all others obtained in the same way, naturally of no value. But very considerable variations in the amount of chlorine eliminated daily and hourly may occur, not only in different individuals, but also in the same person under conditions of health. This follows partly a certain rule. Thus, in all healthy persons examined, the maximum chlorine elimination occurs in the afternoon, and the minimum at night. Hegar found as the mean hourly elimination in eight indi- viduals : afternoon, 0-57 ; night, 0-28 ; forenoon, 0-48 grm. The same author found in the same individual variations in the hourly elimination from 0-20 to 1-32 grm., so that the hourly maximum exceeded the minimum more than sixfold. The following are doubtless the causes which produce an in- crease or a diminution in the chlorine elimination in healthy persons : 1. The taking into the organism of a greater or less amount of chlorine, especially of common salt, which we eat with our food, has without doubt the greatest influence. Persons who eat much salt with their food have a greater average elimina- tion of chlorine, and a temporarily increased ingestion of chlo- rine results, as a rule, in a temporary increase in the elimina- tion. That the greatest hourly chlorine elimination in all persons examined here occurs during the afternoon and even- ing hours, depends, without doubt, chiefly upon the fact that all of these persons eat the greatest amount of salt with their principal meal at noon, a part being eliminated soon after its Digitized by Microsoft® QUANTITATIVE GHANGBS IN TEB UBINE. 491 passage into tlie blood. But also direct experience shows tliat after tlie increased ingestion of chlorine there is an increased elimination witli the urine and vice versa. Falck eliminated with the urine daily : 1. When eating food well salted — on the first day, 6'0 grm. CI ; on the second, 7"8 grm ; on the sixth day, 10'3 grm. 2. When eating food not salted — on the first day, 2'5 grm. 01 ; on the second, 1-6 grm., and on the third day, 0*9 grm. Several persons here took, for the purpose of experiment, common salt in non-purgative doses. In all cases the hourly elimination with the urine was increased ; it rose from 0*4 grm. to I'O, and even to 1*8 grm. In some the chlorine which was absorbed into the blood was again separated from it in large amount and quickly, but in others in smaller quantity and more slowly. In experiments which Stokvis undertook, the amount of chlo- rine in the urine diminished rapidly with the diminution of the amount ingested, and rose again gradually when more salt was eaten. 2. But the amount of chlorine eliminated with the urine de- pends not only upon the amount ingested, but may be increased or diminished by other circumstances, and even by conditions which lie within the organism itself. In all of the persons ex- amined by Hegar, the hourly elimination in the forenoon hours (0'48 grm.) was much greater than during the night (0-28 grm.), although one of these persons was accustomed to eat a meal of weU-salted food in the evening, and then take nothing but a glass of water until the next noon, and the others also ate food rich in salt in the evening, but in the morning only food con- taining but little salt (coffee and rolls) ; so that in all of these cases there must have been other causes which diminished the power of the kidneys to eliminate chlorine during the night and increased it during the forenoon. Without doubt these causes are, on the one hand, the physical and mental quiet during sleep, and on the other, the greater activity of metamor- phosis during the morning, causes which, as has been already shown, exert an analogous influence upon the amount of the urine and of the ilrea. An exceptional case, agreeing with this theory, occurred in one of the persons examined by Hegar, who was accustomed to strenuous mental exertion during the greater Digitized by Microsoft® 492 SEMIOLOGY OF HUMAN URINE. part of tlie niglit, in whom tlie mean hourly amount of chlorine in the night urine (0-47 grm.) exceeded that in the morning urine (0"44 grm.). I have also frequently observed myself that the elimination of chlorine was temporarily considerably in- creased by an increase of physical and mental labor. Agreeing with this also, the observation has been made that drinking a large amount of water, which excites the activity of the kidney and increases not only the amount of urine but also the amount of urea eliminated, as a rule, causes also a temporary increase in the amount of chlorine eliminated, followed usually by a diminution or lessening of the activity. Example. H. drank in the evening four glasses of water. The hourly elimination of chlorine, which averaged in this per- son only 0"13 grm. during the night, rose during the next hours to 0"60 grm., then fell to 0*12, and later to O'lO grm., and rose again in the morning without anything more having been eaten by increased metamorphosis (riding) to 0'51 grm. H. V. drank in the afternoon four glasses of water. The hourly chlorine elimination thereupon increased during the evening hours to 1"89 grm., and averaged during the night 0"57 grm. (instead of 0"38 grm.). In the morning two glasses more of water were taken, in spite of which the amount remained during the whole day below the normal (0"42 grm.), and even fell during the night to 0"014 grm. ( ! ), in the morning rose again somewhat (to 0'22 grm.), but then fell once more (to 0'18 grm.), notwithstanding that bread and butter with a large amount of salt was eaten. From these results it follows without doubt that the amount of chlorine eliminated depends not only upon the amount in- gested, but that it is influenced much more by other causes, es- pecially those which act generally upon the activity of the kid- neys, producing an increase or diminution in the amount of urine. But it is very difficult to estimate accurately the influ- ence of these conditions upon the elimination of chlorine gen- erally, and particularly in any given case. In order to do this we must give the individual chosen for the investigation a diet absolutely free from chlorine, which would, however, certainly disturb the purity and usefulness of the results obtained, or we must take the greatest care to estimate accurately the amount of chlorine in all of the food taken while the investigation lasts, Digitized by Microsoft® QUANTITATIVE CHANGES IN TEE UBINE. 493 as lias been done by Barral in some cases in his careful investi- gations.* "We will now turn to the consideration of the elimination of chlorine in disease. In this subject I have a very large number of experiments, part of which I have performed myself and part have superintended. The results are chiefly as follows : 1. In all acute febrile diseases the amount of chlorine elimi- nated with the urine diminishes rapidly, frequently sinking to the minimum, almost to complete disappearance, so that some- times it amounts to scarcely the one-hundredth part of the nor- mal. With commencing recovery it increases, and during con- valescence sometimes exceeds the normal. Its curve usually runs parallel with that of the amount of urine, for the most part, however, in the opposite direction to that of the specific gravity and the coloring matters, and at the beginning to that of the urea, but during convalescence frequently parallel with that of the urea. Example. In the case of a man with severe pleuropneumonia the chlorine diminished rapidly, amounting on the third day after the commencement of the disease to 0-6 grm. daily, on the next day to 0-3 grm., and on the following to almost 0, from which time it increased continuously with the decrease of the disease and the increase of the appetite, with tolerable regu- larity, until the normal was reached (0-4 — 1-8 — 2-6 — 5-5 — 9-0 grm.). From this time the curve became irregular, and some- times exceeded the normal (10-7— 13-5— 9-7— 11-9— 15-9— 10-8 grm.). In a typhoid-fever patient it fell quickly to a minimum, re- maining for several days almost at 0. Then it increased with advancing recovery gradually, with variations, until it reached the normal. In a woman with acute rheumatism and pericarditis it fell during the acme to 1*0 grm., and rose gradually during con- valescence to 6"3 grm. In a young man with severe febrile bronchial catarrh it fell quickly to 0'8 grm., and then rose during five days to 10'6 grm. In an older man also with febrile bronchial catarrh it fell to * J. A. Barral, Statique chimique des animaTox, appliquee specialement S, la question du sel, Paris, 1850. Digitized by Microsoft® 494 SEMIOLOGY OF HUMAN UBINK 1-1 grm., but tlien rose during convalescence, when an abun- dant amount of nourisbment was taken, to the enormous height of 20-5 grm. In a man with exudative pleurisy it diminished to a mere trace, and then rose again with some variations, without, how- ever, reaching a very high figure (3'0 — 3"2 — 4-8 — 1"6 — 4"0 — 4'5 — 4-9^-6 grm.). The cause of this very great diminution in the amount of chlorine eliminated in all acute diseases is, without doubt, chiefly the diminution of the appetite and the meagre diet, poor in salt, taken by such patients ; the separation of chlorine from the blood by other channels (watery diarrhoea, serous exuda- tions) sometimes causes it. By all of these conditions the amount of chlorine in the blood is certainly diminished, and since, as we see in health, the excess of chlorine in the blood is preferably separated by the kidneys, it is very probable that the amount of chlorine in the urine is diminished. The amount of chlorine eliminated with the urine is also directly dependent upon the amount of urine, and the circum- stance, that this is always considerably diminished in all acute febrile diseases, probably diminishes also the amount of chlo- rine compounds eliminated. Since the above statements concerning the elimination of chlorine with the urine in disease, based upon numerous in- vestigations of my own, were published, several works upon this subject have appeared, such as that of Howitz and Hin- kelbein mentioned above, and those of Alfr. Vogel, Moos, and Brattler mentioned in connection with urea, which also dealt with the elimination of chlorine with the urine. They confirm, in the main, the above statements, and especially that it is not in single forms of disease only that the diminution in the amount of chlorine is observed, for example, in pneumonia, but in the whole class of the above-mentioned diseases, so that the diminution or the disappearance of the chlorine compounds from the urine cannot, as some state, be used for the purpose of making a differential diagnosis, of pneumonia, for example. My results have been confirmed by those of Howitz and Fel. Hoppe * in this respect also — that this diminution of the chlo- * Deutsche Klinit, 1858, No. 5,3. Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 495 rine is particularly dependent upon the diminislied ingestion of chlorine (naturally together with the other causes mentioned above). An exception to this rule, which otherwise applies to all acute febrile diseases, is intermittent fever. In this disease the elimination of chlorine with the urine appears usually to be in- creased, in many cases to a very great extent, during the par- oxysm, sometimes shortly after it, and more rarely shortly before it. Example. "W. K. suffered with tertiary intermittent. Shortly before the attack the hourly amount of NaCl eliminated with the urine was 0-07 grm., during the paroxysm it rose to 0-62 grm., then fell to 0-39 grm., and in the following interval to 0-17 grm. During the next paroxysm it increased again to 0'93 grm. and fell again during the interval to 0"04 grm. A. S. Tertiary intermittent. The hourly amount of chloride of sodium was 0'05 grm. before the paroxysm, rose to 2'5 grm. (!) during it, fell again to 0-12, and then rose again gradually to the normal, since there were no more attacks. A. C. Tertiary intermittent. The hourly elimination of chlo- ride of sodium amounted to 0'42 grm. before the attack, rose to 1'30 grm. during it, and then fell to 0'15 grm. It rose again toward the end of the interval, reached its maximum of 0"63 grm. shortly before the beginning of the fever, and then fell to 0-08 grm. The same rule naturally applies to women. Auguste S. suffered from tertiary intermittent. The hourly elimination of chloride of sodium amounted to 0-15 grm. shortly before the attack, during the paroxysm it reached the enormous height of 412 grm., and fell again after the paroxysm to 0-06 grm. The average daily elimination of chlorine in intermittent fever is, however, somewhat less than normal, but it does not for any length of time undergo the considerable diminution which is observed in other acute diseases ; this is due to the fact that intermittent-fever patients frequently have during the interval a good appetite and eat food with the ordinary amount of salt. The increased elimination during the paroxysm is pro- bably due to the increased blood pressure in the Malpighian bodies of the kidneys during the chilly stage. A diminished separation of chloride of sodium from the blood, which has be- Digitized by Microsoft® 4:96 SEMIOLOGY OF HUMAN URINE. come poor in salt, then naturally follows the increased elimina- tion. 2. In chronic diseases the elimination of chlorine is subject to great variation. As a rule it is diminished, corresponding to the diminished metamorphosis and ingestion of food by such patients, but in individual cases it is, on the contrary, increased. Some groups of diseases belonging under this head are of special interest in this respect and deserve a more accurate consideration. The chlorine apppears to be increased in diabetes insipidus, sometimes temporarily, sometimes for a long time together with an increase in the amount of urine and of the solid consti- tuents generally. In one case of this kind I found the elimina- tion of chlorine with the urine increased for a long time, so much that on one day the enormous amount of 29 grm. was reached. In dropsy at the time when the elimination of urine is sup- pressed, a part of the salt eaten is held back in the body : it transudes with the dropsical fluid into the tissues. With the appearance of diuresis the elimination of chlorine increases to- gether with the amount of urine, and then sometimes reaches an enormous amount. Thus, in one case, such a patient passed on three successive days 33 ( = 55 grm. NaCl), 28, and 21 grm. of chlorine, and in another the elimination of chlorine rose within twenty-four hours, on account of the influence of a decoc- tion of digitalis, from 4 grm. to 27, without the ingestion of chlorine being in the slightest increased. The same process which is injurious in the first class of cases, diabetes, by with- drawing substances from the economy which are necessary, is beneficial in the latter class, dropsy, by separating the super- fluous material. While a certain amount of chloride of sodium appears to be necessary to the organism, partly for many secre- tions, partly for the purposes of intermediate metamorphosis, secretion of the gastric juice, the bile, and for the formation of many tissues (especially cartilage ?), nevertheless an excess of it may be injurious, namely, by preventing the formation of the blood and by displacing albumen.* * Concerning this last property I have already given a detailed treatise in the Handhuch der spec. Pathologie und Therapie, published under B.. VirchoVs revision, Bd. 1, page 404, et seq., and I must here refer to that treatise. Digitized by Microsoft® QUANTITATIVE CHANQEa IN TEE UBINE. 497 A quantitative estimation of the amount of chlorine elimi- nated with the urine may in the present state of our knowledge give the practising physician information upon the following points : In all acute diseases a progressive diminution of the chlorine shows an increase, and progressive increase of the chlorine, a diminution of the disease. If the chlorine falls to a minimum (below 0-5 grm. daily), the conclusion that there is a consider- able intensity of the disease, a complete failure of the appetite, or, under certain circumstances, a previous abundant watery diarrhoea or moderate serous exudation is warranted. If the chlorine increases again in the urine we may, from its amount, draw a tolerably accurate inference as to the condition of the appetite and digestion of the patient. In all of these cases a very approximate estimation of the amount of chlorine is usually sufficient, and an error of 50 or 60 per cent, is of no importance, especially in cases where the elimination of chlo- rine is very slight. In chronic diseases the amount of chlorine is of importance to the physician, since it is a tolerably accurate measure of the digestive power of the patient. An abundant amount of chlorine (6-10 grm. daily) permits us to infer that digestion is good, a small amount (below 5 grm.) shows a weak digestion, providing that no large amount of chlorine is separated by other channels, as, for example, by abundant watery dejections, or any other moderate exudation, or that the diet of the patient has uninten- tionally been so chosen that a very small amount of chlorine is ingested. A very much increased chlorine elimination (more than 15-20 grm.) indicates diabetes insipidus, provided that there has not been an increased ingestion with food or drugs. Only in hydrsemia and dropsy is it a good sign. The considera- tion of the other urinary constituents serves often to strengthen or to modify the inferences drawn from the amount of chlorine alone. § 130. SuLPHUEic Acid.* The methods for determining quantitatively the amount of * G. Gruner, Die Ausscheidung der Schwefelsaure durch den Ham, Glessen, 1853. Wald. Clare, Experimenta de excretione acidi sulfurici per urinam. Dor- pat, 1854. P. Sick, Vers, iiber die Abhangigkeit des Schwefelsauregehalts des Urines von der Schwefelsaurezufulir, Inaug. AbMlg., Tubingen, 1859 32 Digitized by Microsoft® 498 BEMIOLOGT OF HUMAN UBINE. sulphuric acid in the urine have been already described in § 69, Both the gravimetric and the volumetric methods, when they are carefully performed, give very accurate results. If it is de- sired to obtain the result very quickly, the volumetric method should be used without boiling, since this operation is usually inconvenient for the physician. But the result is then less ac- curate, and the error may reach 10 per cent. An approximate estimation, which will not accurately give the amount of sul- phuric acid contained in the urine, but will only show whether it exceeds or falls below a certain point, may be performed still more quickly, and is sufficient for most purposes of the phy- sician. An example will explain the principle and the per- formance. We will take the case in which the physician wishes to know whether the elimination of sulphuric acid with the urine of a patient is comiderably increased or diminished. The average normal amount of sulphuric acid in the urine daily is about 2 grm. The patient whose urine is to be examined has passed 2,000 cc. in the twenty-four hours. If this contains the normal amount of 2 grm., then 100 cc. of it, which are taken for analy- sis, will contain O'lO grm. of SO3. To this 100 cc. is now added, after it has been acidulated, an amount of chloride of barium equivalent to 0*05 grm. SO3, and filtered. If the filtrate is not rendered turbid by more chloride of barium, we know that the patient is secreting less than 1 grm. of SO3 in twenty-four hours, and, therefore, that the elimination of sulphuric acid is considerably diminished in his case. If the filtrate is rendered turbid, however, by the addition of more chloride of barium, enough more must be added to correspond to 0"05 grm. of 80^. If then, after filtering, a turbidity is caused by the addition of chloride of barium, the amount of sulphuric acid in the urine exceeds the normal. Such approximate estimations, which are entirely sufficient for many practical purposes, may be per- formed in a few minutes, and in a clinic, directly at the bed- side. Even in cases in which a more accurate estimation is de- sirable, they may profitably be performed as a preliminary to a more careful analysis. The average amount of sulphuric acid eliminated with the urine in health has been established with tolerable certainty by different observations in various places. Thus Gruner, who Digitized by Microsoft® QUANTITATIVE GHANaES IN THE UBINE. 499 made his investigations in Giessen upon seven young men, found as tte average of the daily elimination 2-094 grm. Of these seven persons the average in those who passed the least sulphuric acid was 1-509 grm., and in those who passed the most was 2-485 grm. These figures, reckoned for 100 kilogr. weight of the person, give as the average 3-19, minimum 0-85, maximum 3-73 ; reckoned for 100 ctm. height of the person, give as the average 1-18, minimum 1-04, maximum 1-35. Clare found that the average daily elimination for 15 days in a young man in Dorpat was 2-288 grm., minimum 1-858, maximum 2-973. Neubauer found in one of two men living in Wiesbaden as the daily average (for 17 days) 2-48 grm., minimum 1-90, maximum 3-21 grm. In the other the average for 22 days was 2-27, mini- mum 1-70, maximum 3-20 grm. Sick found as the average in his own case 2-46 grm. Weidner, 2*1 grm. Therefore the aver- age daily elimination of sulphuric acid with the urine in healthy, well-nourished men varies between 1-50 and 2-50 grm. Gruner and I have made direct experiments upon the hourly elimina- tion of sulphuric acid in health and upon its variations. Prom these it follows that the general hourly average is about 0-090 grm., that in the afternoon is 0-108 grm., in the night 0-070 grm., and in the forenoon 0-063 grm. Prom this the general rule fol- lows that the elimination of sulphuric acid is most abundant a few hours after the principal meal, and then falls constantly until the time of the principal meal on the following day, after which it begins to rise again. But with different individuals the elimination of the sulphuric acid taken into the body with the food takes place with more or less energy, more quickly or more slowly, so that the sulphuric acid curve becomes more or less steep. But the variations in the hourly elimination of sulphuric acid are very considerable in the same person. Thus one person evacuated in one hour a maximum of 0-165 grm., and at another time in two hours an amount so small that it could not be estimated, at the most, therefore, a couple of milli- grams. In another person the hourly maximum was 0-317 grm., and immediately afterward only 0-016 grm. were passed per hour. As to the catises which influence an increase or diminution of the sulphuric acid elimination in health, the investigations have been quite numerous. Digitized by Microsoft® goo SEMIOLOGY OF HUMAN URINE. It follows from tlie aboTe reported rate of tlie hourly elimina- tion of sulphuric acid, that it depends to an important extent upon the amount of sulphuric acid or other sulphur compound, which is conyerted within the organism into sulphuric acid, taken into the body with the food. But it is also proven by numerous experiments, that sulphur compounds which are taken into the body in other ways, as for example as drugs, cause an increase of the SO3 elimination. The investigations hitherto made in this respect teach us the following points : 1. The elimination of sulphuric acid is increased by the in- gestion of sulphuric acid, sulphates, and other sulphur com- pounds whose sulphur may be oxidized within the body to sulphuric acid. Examples. In the case of a patient in my clinic, who took SO3 for a long time on account of haemoptysis, the daily sulphuric acid elimination was increased from 1"2 grm. to 3"0 and even 3-28 grm. Also in a case of SO3 poisoning, the amount of it in the urine during the first 24 hours was much increased. (Mannkopff.) In several experiments the hourly elimination of sulphuric acid was much increased by taking sulphate of sodium. Thus in one it was increased from 0'049 grm. to 0"122 — 0'176 — 0"145 and 0-220 grm., and in another from 0-041 to 0-138— 0-122 and 0-164 grm. This increase continued sometimes for a longer and sometimes for a shorter time, that is, the sulphuric acid ingested was separated from the body in some cases quickly and in some more slowly. (Gruner.) According to Krause * the internal use of sulphur increases the amount of sulphuric acid in the urine ; it is also increased, according to the experiments of Boecker and Clare, after large doses of sulphur auratum antimonii (golden sulphur). It follows from the experiments of Sick that small doses of sulphate of sodium taken internally are completely absorbed and eliminated with the urine, while only a part of large doses appears again in the urine — which would be expected on ac- count of the cathartic action of large doses of Glauber's salt (sulphate of sodium). 0. Gaethgens t found also that in dogs after the injection of *A. Krause, De transitu sulfuris in urinam, Dorpati, 1853. \ Centralbl. f. d. medic. Wissensch., 1873, p. 833, et seq. Digitized by Microsoft® qUANTITATIVB GSANGES /JV" THU URINE. 50I dilute sulphuric acid into the stomach its amount in the urine was considerably increased (from 2*7 to 7'1 grm.). 2. The sulphuric acid elimination is very decidedly increased after the abundant ingestion of meat, which is probably due to the separation during digestion of the sulphur which is in combination with the protein substances jn the meat, and its gradual oxidation in the blood to sulphuric acid, in which form it is eliminated with the urine. This increase of the SOs ia the urine after eating meat sometimes appears quickly, a few hours after eating, and sometimes not for a long time, 12-24 hours, a difference which is probably due to the greater or less rapidity of digestion. On the other hand, the sulphuric acid elimination is diminished by a predominance of vegetable food. Examples. A person who had eaten in the evening a very hearty supper consisting chiefly of meat, evacuated from 12 o'clock at midnight to 9 o'clock in the morning 0*50 grm. of SO3 per hour instead of 0*10 grm., and during the next 24 hours it amounted to the enormous sum of 7'3 grm. (!) instead of the daily average of 2 '02 grm. Several persons, whose metamorphosis I investigated, con- stantly eliminated more SO3 when they had eaten meat on the previous evening, and less when they had eaten no meat but only bread and butter, rice, and similar substances. Very instructive in this respect is a series of experiments which Clare made upon himself. During three days he took only a meat diet, and in this time evacuated, on the first day 2-094, on the second 5-130, and on the third 3-868 grm. of SO3. Then for two days he ate ordinary food and evacuated on the first day 3-592, and on the second 2-262 grm. of SO^. On the three following days he lived upon an exclusively vegetable diet, when the amount of SO3 was on the first day 2-262, on the second 1-394, and on the third 1-022 grm. ; on the two follow- ing days with ordinary diet it was 1-979 and 2-859 grm. It is plainly seen here that the increase of the SO3 caused by the meat diet first appeared on the second day, but extended over into the first day of the ordinary diet; in like manner the di- minution of the SO3 caused by the vegetable diet first appeared on the second day and extended over into the first day of the ordinary diet. Therefore, in these cases the action appeared later than in those which were observed by me, probably on Digitized by Microsoft® 502 SEMIOLOQT OF HUMAN URINE. account of individual predisposition, and for this reason proba- bly anotber experiment of Clare, in whicb he ate on alternate days a meat and vegetable diet, gave no positive result. Does the amount of sulphuric acid eliminated with the urine always depend entirely upon the amount ingested, or are there, as with common salt, cases in which the elimination of this substance is increased or diminished by other conditions, so that the system gives up a portion of its usual, fixed, normal amount of sulphur or sulphuric acid, whereby it becomes poorer in this constituent than usual, or, on the contrary, holds back a portion of the sulphuric acid obtained from without, and thereby becomes richer in this constituent than usual? This question cannot yet be answered with certainty. Gru- ner and Clare have endeavored to determine by experiments whether rest or strenuous exertion exerted any influence upon the SO3 elimination. None of their experiments gave a satis- factory result. Drinking a large amount of water, which de- cidedly increases the secretion of urea and chloride of sodium, has no marked influence upon that of sulphuric acid. But we are not yet warranted in concluding from these experiments that the SO3 elimination is not afi'ected by such influences : it may have been very slight, or have been prevented in these ex- periments by opposing influences. The fact mentioned above, that the sulphates or sulphur constituents of meat which is eaten are eliminated rapidly by some persons and more slowly by others, renders it extremely probable that there exist still other considerations lying within the organism itself, which regulate the SO3 elimination, and that this power varies in dif- ferent persons and in the same person under different circum- stances. Also the experience often met with, that sulphates taken for a long time in digestible doses exert a decidedly dif- ferent action, is to my mind a proof that under certain circum- stances an amount of them greater than the normal may be retained within the organism. A definite answer to this ques- tion can only be obtained by either accurately, estimating the amount of sulphur and sulphuric acid in the blood and other parts of the body under different circumstances, or by simul- taneously accurately determining quantitatively the amount of sulphuric acid eliminated from the body and thq,t taken into it. Both of these requirements are so difficult to fulfil, that this Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 503 question will probably remain unanswered for a long time to come. As to the sulphuric acid elimination in disease I have made quite a number of investigations, without as yet having arrived at any very valuable result. In most acute febrile diseases I found the SO3 very much diminished, which was without doubt due to the scanty diet and the predominance of vegetable food in such cases. Examples. A man suffering with buccal diphtheria with vio- lent fever evacuated in the twenty-four hours only 0-5 grm. of SO3. A patient with catarrhal fever 0-29 and 0-38 grm. One with pleurisy 0'63 grm. An exception occurred, however, in three cases of severe pneumonia, in which the sulphuric acid was partly slightly diminished and partly considerably, in- creased. One of these patients, who was treated with large doses of digitalis, evacuated 2-4— 3-1 — 2-9 — 5-7 — 4-3 — 1-8 — ll — 1'6 — ^2-7 grm. Of the other two, in whom the pneumonia rapidly proved fatal, one eliminated 2*9 and 1"4 grm., and the other on the day of death 4"4 grm. A girl with severe rheumatic fever eliminated at the acme of the disease 0"8grm. One with facial erysipelas passed 0"48 grm. In chronic diseases also the sulphuric acid elimination was very slight in many cases, in others somewhat greater, but still considerably below the normal. In dropsy, at the time when, on account of diuresis, the chlorine elimination is so enormously increased, the sulphuric acid, as a rule, remains below the nor- mal. In chronic diseases the SO3 was found to be increased almost only after the use of sulphuric acid or sulphates, and in diabetes where an abundant meat diet was eaten. Examples. A patient with icterus passed 1'4 grm. of SO3, and one with rheumatism of the neck I'll grm. A patient with emphysema of the lungs 1'2 grm., one with amenorrhoea 0*5 grm., a girl with leucorrhoea 0*7 grm., and a patient with habi- tual hypermenorrhoea 0-97-1 '1 grm. A dropsical patient, after diuresis had commenced, passed in twenty-four hours 33 grm. of chlorine with the urine, but in the same time only 1 grm. of SOy and on the following day when he passed 28 grm. of chlo- rine only 0-5 grm. of SO,. A patient who had taken SO3 elimi- nated in twenty-four hours over 3 grm., and one with diabetes insipidus up to 5"2 grm. of SO3. Digitized by Microsoft® 50 i 8EMI0L0GT OF HUMAN URINB. According to Bence Jones, in those diseases in whicli the muscular system is especially attacked, as in chorea, also in diseases of the brain, both functional, as in delirium, and or- ganic, as in inflammation of the brain, the sulphates in the urine should be considerably increased. Heller claimed the same for inflammatory diseases, while, according to him, the SO3 should be diminished in chlorosis, the neuroses, and in chronic renal and spinal afiiections. The methods, however, which both of these investigators used were not sufficient to decide this difficult question. Single observations which Leh- man and Gruner made are not favorable to that view. My own observations in those diseases have not been sufficiently numer- ous to enable me to draw any definite conclusions either for or against them; the three cases of pneumonia reported above appear at all. events to favor the view that in many inflamma- tory diseases the SO3 increases. The physician can, in the present state of our knowledge, draw the following conclusions from an increase or diminution of the sulphuric acid in the urine : 1. A considerable diminution of the SO3 indicates that the patient has eaten very little animal food, or only vegetable food ; 2. An habitual, abundant sulphuric acid elimination in con- nection with a large amount of urea, indicates a preponderance of animal food. A temporary and considerable increase allows us to conclude that sulphur, sulphuric acid, sulphates, or large quantities of meat have been eaten ; 3. Only in those cases of violent febrile diseases, where little or nothing is eaten, and in which the SO3 appears to be con- siderably increased, can the conclusion be drawn that this in- creased elimination is due to an increased decomposition of those constituents of the body. § 131. Phosphoric Acm.* The most convenient and best method for estimating quanti- ^ A. Winter, BeitrSge zur Kenntniss der Urinabsonderung bei Gesunden, Giessen, 1853. F. Mosler, Beitrage zur Kenntniss der Urinabsonderung, Gies- sen, 1853. W. Brattler, Ein Beitrag zur Urologie, Milnchen, 1858. H. Krabbe, Ueber die Menge der Pbosphorsaure im Ham, etc., Virchow's ArcMv, 1857, Digitized by Microsoft® QUANTITATIVE CHANGES IN THE URINE. 505 tatively tlie amount of phosphoric acid in the urine is the volu- metric method with oxide of uranium, described in § 67. Formerly ferric chloride was used for this purpose instead of the oxide of uranium, but it gives much less accurate results. The investigations mentioned above, and those reported in the following pages, were mostly performed with ferric chloride. Tet the results agree closely enough with those which were ob- iaiaed by H. v. Haxthausen under my direction, and in which the oxide of uranium was used. There are numerous series of investigations concerning the daily and hourly elimination of phosphoric acid in health. Breed found as the average amount in twenty-four hours in four individuals 3-7 grm. ; "Winter, in one person, 3-7, in a second, 4-2, and in a third, 5-2 grm. ; in the same person at two different times, 2-4 and 3-7 grm. ; Neubauer found in one individual 3-1 grm., in another only 1-6 grm. ; Aubert found 2-8 grm. ; v. Hax- thausen found in a large series of investigations upon his own urine from 3-11 to 5-58 grm. ; Eiesell, 2-7 to 2-9 grm. We may, therefore, consider about 3 '5 grm. as the average amount of phosphoric acid eliminated in twenty-four hours by a male adult, although it must be observed that the individual ave- rage may vary very considerably from this figure. The average hourly amount is, therefore, about 0'15 grm. Winter has cal- culated the amount of PO^ for the weight and height of the body, and found that the average hourly amount for 100 kilogr. is 0*27 grm., and for 100 ctm. is O'l grm. The daily and hourly variations existing in the same indi- vidual under conditions of health are very great. Thus, Neu- bauer found that the daily maximum in one individual was 2-16 grm., the minimum, 1*21 grm. ; in another, the maximum was 4'88 grm., the minimum, 2'44 grm. ; Hosier found as the maximum, 4'86 grm., as the minimum, 2'40 grm., etc. Still greater dif- ferences are found when the hourly amounts eliminated are compared with each other. I found in a long series of obser- vations in the same individual that the maximum hourly elimi- xi., p. 478. H. v. Haxthausen, Acidum phosphoricum urin« et excremento- rum, Diss, inaug., Halle, 1860. E. BischofE, Die Ausscheidung der Phosphor- sSure im Thierlserper. A. Eiesell, Uelier die Phosphorsaureausscheldung im Ham bei Einnahme von kohlensaurem Kalk (Hoppe-Seyler, Med.-chem. Un- tersuchungen, Heft 3, 1868). Digitized by Microsoft® 506 SEMIOLOGY OF HUMAN UBINB. nation was 0-216 grm., the minimum, 0-085 grm. ; both extremes occurred on one day, while the whole series of observations lasted during ten days. The observations of "Winter, Mosler, Haxthausen, and myself, which exactly agree, show that the hourly elimination of phos- phoric acid is very regular, and in all of the individuals exam- ined by us shows a very uniform course. It begins to rise in the afternoon hours (after the principal meal), reaches its maxi- mum in the evening, falls during the night, and reaches its minimum in the forenoon hours. The following table shaws these differences in the various portions of the day in four individuals. The amount of PO^ eliminated in one hour : Afternoon. Night. Forenoon. By A, was 0-18 0-30 0-13 grm. " B, " 0-38 0-21 0-11 " " 0, " 0-18 0-16 0-10 " " D, " 0-11 0-14 0-11 " This table is instructive by showing how every general rule is modified in different persons by the individual peculiarity. In B, the curve is the steepest, the difference between the after- noon and the forenoon being the greatest. In this case, the greater part of the POj taken with the food was eliminated quickly, the summit of the curve falling in the afternoon hours. In the case of C, the elimination took place more slowly, the summit of the curve falling in the evening hours. In the case of D, the elimination occurred still later, perhaps on account of slower digestion, and the summit of the curve fell in the night hours, although D took his principal meal at the same hour as A, B, and C, at one o'clock p.m. As to the causes upon which the increase or the diminution of the phosphoric acid elimination with the urine depend, the facts thus far obtained teach us the following : 1. The phosphoric acid in the urine increases after taking phosphoric acid or soluble phosphates into the organism. Aubert * found that the amount of PO5 evacuated with the urine, the normal amount in twenty-four hours being 2-8 grm., * Henle u. Pf Buffer's Zeitschrift ffir ration. Medicin., 1852, ii. 3. Digitized by Microsoft® QUANTITATIVE CEANGM8 IN THE URINE. 507 rose after tlie ingestion of 31 grm. of sodic phosphate to 4-1 grm. Von Haxthausen found also that there was a regular increase ill the elimination of phosphoric acid with the urine after tak- ing sodic phosphate. 2. The phosphoric acid in the urine increases or diminishes according as more or less phosphoric acid already formed, or substances which are capable of being transformed in the body into phosphoric acid are taken into the organism with the food. It diminishes during fasting, but without entirely disappearing during long-continued starvation, as is the case with the chlo- rine. As a rule, a greater amount is eliminated upon a meat diet, a less upon a vegetable diet. Hosier found that during fasting the PO5 diminished almost one-half; and that it increased almost to double its original amount upon a diet rich in protein substances. Schmidt observed that a cat weighing 1 kilogr. upon an un- restricted diet eliminated in twenty-four hours 0'30 grm. PO5, but on long fasting only 0"107 grm. The fact which was proved with certainty above in the ease of chlorine, and was shown to be very probable in that of sul- phuric acid, that their elimination depends not merely upon the amounts taken into the organism from without, but that it is also regulated by conditions lying within the system, changes of metamorphosis, etc., applies also without doubt to that of phosphoric acid. Many facts speak decidedly in favor of this view. It has been already shown above, that different indi- viduals eliminate the phosphoric acid taken with the food with varying rapidity. It follows, from the observations made by me, that a remarkable diminution of the phosphoric acid elimination (0'084 grm. per hour) may succeed a temporary increase of the same (0'216 grm.«per hour). The phosphoric acid elimination is, as a rule, increased by drinking abundantly of water simultaneously with that of the urea and chlorine, and, indeed, by an amount much greater than that of the phosphates contained in the water ; it is, therefore, caused either by the increase of the general metamorphosis, or by the increas^e of the excretory activity of the kidneys, or by both together. It follows certainly, from these facts, that the organism under cer- tain conditions may contain an increased amount of phosphates Digitized by Microsoft® 508 SEMIOLOGY OF HUMAN URINE. on account of tlie retention of those ingested, or a diminished amount on account of their increased elimination. It is also certain that the knowledge of these conditions has the greatest importance for the physiologist as well as the physician, but what we do know at present concerning them is partly frag- mentary and partly conjectural, possessing no certainty, but at the most probability. Although it now appears important and even necessary to explain these conditions by accurate series of investigations, yet we meet the same obstacles which were brought forward above in reference to the determination of the analogous conditions in the case of chlorine and sulphuric acid. One of these is that all of the phosphoric acid is not eliminated by the kidneys, but the faeces also usually contain phosphates.* Therefore, either the amount of the phosphoric acid contained in different parts of the body under different circumstances must be quantitatively determined by a very large series of investigations, or the amount ingested with the food, etc., to- gether with that eliminated with the urine and faeces, must be accurately estimated. But this wish must remain for a long time ungratified on account of the difficulty of the circum- stances, and until then our ideas concerning the increase or diminution of the phosphoric acid in disease must be only con- jectural, and it is not my intention to enter more fully into this subject here. Kiesell found that the amount of phosphoric acid eliminated with the urine was diminished after the ingestion of a large amount of chalk, since a large portion of it combined with cal- cium passed with the faeces. This diminution, however, was only temporary (two days), since the phosphate of calcium formed in the intestine was later absorbed and eliminated with the urine. Direct investigations, of which I possess a large number * Upon this point Von Haxthausen has performed some experiments under my direction. He found that the following amounts of phosphoric acid — ob- tained, not by ignition, but by extracting the faeces with dilute nitric acid — were evacuated with the excrement in twenty-four hours : Average (of sev- enteen observations) = 0"666 grm. ; maximum = I'OSO grm. ; minimum = 0'370 grm. Hence, the amount separated with the urine is four or five times greater than with the fseces. Biesell (see above) found that the amount of phosphoric acid in the fajces was increased by the ingestion of chalk. Digitized by Microsoft® QUANTITATIVE ORANGES IN THE URINE. 509 (more tlian 1,000), as to the amount of phosphoric acid elimi- nated by patients, have taught me the following : In acute diseases of a mild grade the foUowing course of the elimination is frequently observed : It diminishes somewhat duriQg the first days, probably on account of the scanty diet, then increases again gradually as the patient eats more. It sometimes exceeds the normal during convalescence with the increased ingestion of food. In diseases of this kind of short duration, even when they are accompanied by severe fever, the diminution of the phos- phoric acid is sometimes very inconsiderable and scarcely ob- servable. Examples. In a young man with severe angina tonsillaris febrilis the PO5 on the day of his entrance into the hospital amounted to 2"8 grm. An emetic was given, followed by violent vomiting. Scanty diet. On the next day PO5 = 1"7 grm. Patient became better, \ diet. On the following day PO5 = 2'6 grm. ; on the next 2 '5 grm., ^ diet. On the following day 3 '2 grm. PO5. Discharged well. Pneumonia levior. The patient was able to be discharged well after eight days. PO^ = 3-4^2-5— 2-9— 2-4^2-3 grm. Severe pneumonia, at the height of the disease : 1"7 — 0'8 — 2'1 — 1-2— 0-9— 2-1— 1-9— 1-1 grm. Severe pneumonia : 1-6 — 1-4 — 2*2 — 2-3 — 1-6 grm. Bronchial catarrh with fever : 1-4 — 1-5 — 1-7 — 1-5— 2 '8 grm. Convalescence from a severe pneumonia : 3 '8 — 2*7 — 3 '2 — 3 '5 — 3-9— 1-8— 2-5 grm., etc. The same : 1-9— 5-6— 2-8— 1-5— 3-2— 2-8 grm. Convalescence from a severe febrile bronchial catarrh : 4-8 grm. Catarrh, organ, digest, eczemat. with violent fever. Eapid progress, so that the patient was able to be discharged well in eight days: 2-3— 2-6— 2-7— 2-6— 34 grm. FeTTwles. Eheumatic fever : 2-1— 2-3— 2-2 grm. Gastric catarrh : I'l — 1"2 grm. Catarrhal fever : Height of the disease = 1-6 grm. Convalescence from typhoid fever = 6'2 grm. In many cases in which the disease is severe and the food is Digitized by Microsoft® 510 SEMIOLOGY OF HUMAN UBINE. withdrawn for a long time, or toward death, the phosphoric acid is much diminished. Gases. Girl with seTere catarrh, pulmon. febrilis. At the height of the disease = 0"7 — 0"5 grm. During convalescence = 1-3 — 2'5 grm. Toward death in a case of acute pulmonary tuberculosis: 0-4^0-4— 0-3— 0-3— 0-2— 0-1— 0-08 grm. (day of death). Pulmonary gangrene with fatal termination : 3'0 — 2 "5 — 2*2 — 0'7 grm. In individual cases, however, the PO5 may, during the height of an acute disease, considerably exceed the normal, as the fol- lowing case shows : Severe pneumonia in a man of middle age, who was treated and cured with large doses of digitalis : 4:'3 — 5'1 — 4"1 — 8'4 — 7'9 4-5_2-9— 5-0 grm. In chronic diseases the elimination of phosphoric acid shows a very irregular progress ; it usually remains below the normal, but sometimes increases considerably. Since I possess a large number of series (30-40 observations) of investigations in cases of this kind, the complete report of which would be tedious, I will in the following cases give only the mean, maximum, and minimum values. Modes. Gases. Pulmonary emphysema. Mean of eight days =1*3; max. = 2*3, min. = 0'6 grm. Chronic bronchorrhoea. Mean of eight days '—I'l; max. = 4-7, min. = 1'3. Carcinoma of the liver. Mean of eleven days = 2'2 ; max. = 2 '6, min. = 1'6 grm. Subacute articular rheumatism. Mean of eighteen days = 2-4; max. = 3"1, min. = 1"7 grm. Hemiplegia following apoplexy. Mean of thirty-five days = 2 '7 ; max. = 5 '2, min. =1-0 grm. Hydruria. Mean of three days =5"0; max. =5"8, min. =4*4 grm. Dropsy. Stage of diuresis with great increase of the chlorine eliminated. Mean of two days = 1"8 grm. Females. Diabetes insipidus. Mean of fourteen days = 4-8 ; max. = 7"8, min. = 3'2 grm. Digitized by Microsoft® QUANTITATIVE OHANQEa IN THE UBINE. gn Ascites. Mean of fifteen days = 3*0 ; max. = 4*7, min. = 1"7 grm. Chronic rheumatism. Mean of seven days = 3-3 ; max. = 4-2, min. = 2*7 grm. Spinal irritation. 2-1 — 2*8 grm. Mean =24 grm. Amenorrhoea. 2"1 — 2'3 grm. Mean = 2"2 grm. Scrofula. 2*6 — 5 "2 grm. Mean = 3'5 grm. Pulmonary tuberculosis. 1-5 — 3"9 grm. (ten days). Chronic facial erysipelas. 1-5 — 3'6 grm. (eleven days), etc. Brattler gives the following resume of his investigations in disease : The elimination of phosphoric acid is diminished in diseases and functional disturbances of the kidneys with gen- erally diminished secretion of urine (Morbus Brightii, heart lesions), and in diseases of the digestive organs which diminish the absorption of the food ingested. It is increased in acute febrile diseases by the increased decomposition of the tissues containing phosphorus (the increase, however, is never as con- stant as in the case of urea), and further in those diseases in which by a functional disturbance of the kidneys the phosphoric acid has been held back and accumulated in the blood, after removal of the obstruction (Morbus Brightii, and cholera). Haxthausen observed a diminution of the phosphoric acid elimination in intermittent fever during the interval. E. Mendel * found that in chronic diseases of the brain the amount of phosphoric acid eliminated is, both absolutely and relatively to the amount of the other solid constituents in the urine, less than in healthy persons who eat the same food ; that in maniacs its amount is still less, and increases with recovery; that, on the contrary, it is increased after apoplectic and epi- leptic attacks. In some cases, after sleep was produced by chloral hydrate or bromide of potassium, he found the phos- phoric acid surprisingly increased. Earthy Phosphates. § 132. CALcroM. Magnesium, t In order to estimate quantitatively the amount of earthy (cal- * Die Phosphorsaure im Urin von Gehimkranken, Archiv f. PsycUatrie, 1873, iii., p. 636, et seq. f Beneke, Der phosphorsaure Kalk, etc., GSttingen, 1850. Derselbe, Zur Digitized by Microsoft® 512 SEMIOLOGY OF HUMAN UBINE. cium and magnesium) phosphates in the urine, different methods may be used according to the purpose of such investigation. 1. The amount of earthy phosphates is determined collectively according to Beneke's method. (§ 91, 1.) This method gives a result very quickly, but naturally is only suitable for approxi- mate estimations. 2. The amount of the earthy phosphates is estimated collec- tively according to page 255, b, by precipitating them with am- monia, washing the precipitate, dissolving in hydrochloric acid, and estimating the phosphoric acid in the solution volumetri- cally. In this way the true weight of the earthy phosphates is not found, but only that of the phosphoric acid combined with the earths. Or we may estimate : 3. The calcium and magnesium according to § 76. In order to be able to draw further conclusions from the re- sults which have been obtained by the one process or the other, the following may serve as indications : Beneke considers 1"2 grm. as the normal quantity of earthy phosphates which are passed with the urine in twenty-four hours by a healthy active man. Lehmann passed in twenty-four hours With ordinary diet, . . 1 -09 grm. of earthy phosphates. With purely animal diet, 3-56 " " " Bocker evacuated on the average 148 grm. daily. Hosier found that the amount of phosphoric acid combined with the alkaline earths (not earthy phosphates, therefore), was in his own case, I., during six days in April; II., during four days in October : I. II. Per Day. Per Hour. Per Day. Per Hour. Mean, . 1-153 0-048 0-390 0-015 grm. Maximum, 1-800 0-075 0-660 0-027 " Minimum, 0-370 0-015 0-170 0-007 " Physidogie und Pathologie des phosphorsauren und oxalsauren KaJkes, 2. Beitrag, GSttingen, 1850. Kletzinsky, Heller's Archjv, 1853, p. 270, et seq. C. Neubauer, Ueber die Erdphosphate des Hams, Journ. f. prakt. Chem., Bd. 67, p. 65, et seq. F. Huenke, De phospbatum terrarum in urinse quantitate. Diss, inaug., Berlin, 1859. A. Eiesell (see tbe preceding section). S. Soborow, Ueber die Kalkausscheidung im Ham, Centralbl. f. d. med. Wiss., 1872, p. 609. Digitized by Microsoft® QUANTITATIVE CEANOES IN THE URINE. 513 In another healthy individual the hourly mean was from 0-015 to 0-019 grm. Hegar found that the mean amount of phosphoric acid com- bined with the alkaline earths was, in his own case, 1-31 grm., the observation lasting eight days ; a half year later the mean daily amount of a four days' observation was 0-902 grm. Neubauer obtained, as the result of very numerous investiga- tions, the following values, which deserve the greatest confidence on account of the great number of observations (52) and the ac- curacy of the methods employed. The average mean amount of earthy phosphates which are passed with the urine by an adult man in twenty-four hours, is from 0-941 to 1-012 grm. The average maximum=l-138 to 1-263 (highest number = 1-554). Average minimum = 0-8 (smallest amount=0-328 grm.). The daily amount of calcic phosphate averaged 0-31 — 0-37 grm. Its average maximum=:0-39 to 0-52 grm. (largest amount=0-616 grm.). Average minimum = 0-25 (smallest amount=0-15 grm.). C. Bodeker * found that the daily amount of (JaO passed with the urine by nine young men varied from 0-2 to 0-6 grm. The mean was 0-32 grm. The magnesic phosphate averaged 0-64 grm. The average maximum =0-77 (largest amount=0-938 grm.). Average mini- mum=0-5 grm. (smallest amount=0-178 grm.). On the average, therefore, one equivalent of the phosphate of calcium is evacuated to three equivalents of the phosphate of magnesium, or in 100 parts 33 of calcic phosphate and 67 of magnesic. According to the investigations of Neubauer, calcium salts when ingested do not appear in the urine, or only to very slight extent. On the contrary, W. Eoberts found that after eating, the earthy phosphates were considerably increased in the urine, almost doubled. The experiments of A. Eiesell show than an increase of earthy phosphates in the urine took place after the ingestion of a large amount of chalk, and at the same time an increase in proportion to the amount of phosphoric acid combined with the alkalies. He found that under normal conditions of the * Zeitschr. f ration. Med., 1861, p. 164, e,t seq. 33 Digitized by Microsoft® 514 8EMI0L0QT OF HUMAN UBINE. total amount of phosphoric acid contained in the urine (from 2-7 to 2-9 grm. in the twenty-four hours) about | was combined with the alkalies and | with the alkaline earths. After the in- gestion of chalk, however, the proportion changes during the first two days to about equal parts (i : ^), together with a dimi- nution in the total amount of phosphoric acid contained in the urine (from 1-3 to 1-6 grm. in twenty-four hours), while there is an excess in the fseces. In the next two days, when the amount of PO5 has again increased in the urine (2*2 grm. in twenty-four hours), the proportion becomes reversed, so that about f of the phosphoric acid eliminated with the urine is combined with the alkaline earths and only \ with the alkalies. During these last two days the urine also contains a sediment of the phosphate of calcium, which had formed within the urinary passages. In disease the absolute amount of the earthy phosphates as well as the relative proportion between the calcic and magnesic phosphates appears to vary very much from the above-men- tioned normal. Thus it is almost universally accepted that in certain diseases of the bones (osteomalacia, rachitis, etc.) the elimination of the earthy phosphates, especially, of calcic phos- phate, with the urine is very much increased. For the com- plete explanation of this symptom, important not merely to the pathologist but also to the therapeutist, still more numerous and careful investigations are desirable. But these, in order to give information concerning the metamorphosis of the earthy phosphates as they naturally would, must take account of the earthy phosphates eliminated not merely with the urine but also with the fseces. An increase of the earthy phosphates, especially of the calcic .phosphate, has special importance to the physician, when it leads to the formation within the urinary passages of a sedi- ment which may give rise to the formation of urinary gravel or calculi. For further particulars on this point consult § 135, under the head of calcic phosphate calculi. The urinary constituents considered in the previous sections are those whose quantitative estimations are, for the purposes of the practising physician, of especial importance, since they give the most indications for judging of the processes of meta- Digitized by Microsoft® QUANTITATIVE CHANGES IN THE UBINE. 515 morpliosis in the body, and, moreover, the methods of their quantitative analysis are relatively simple. In certain cases, however, it is desirable to estimate the amount of some other urinary constituents, normal and abnor- mal. We wUl consider these in the following section. § 133. Potassium. Keeatinin. Leucin akd Tykosin. Allantoin. Lactic Acid. Oxymandel Acid. Caebonic Acid. The quantitative estimation of the amount of potassium elimi- nated with the urine is performed according to the familiar methods. (Compare § 78 and § 79.) In many cases this is of interest to the physician, since a diminution as" well as an increase of this substance in the organism is regarded by many as the cause of diseased disturbances. The statements of Weidner may assist in judging of the results obtained by such investigations. This observer evacuated in twenty-four hours on the average 3"91 grm. of KO (max. = 59, min.= 2 grm.). He found that the proportion of potassium and sodium in the urine was as 1 : 1"35. Kreatinin. For its properties consult § 3, and for the methods for estimating it in the urine § 74. The average daily amount in the urine of men is about 1 grm. Neubauer* found in his own urine from 0-6 to 1-3 grm., mean = 1 grm. of kreatinin. In several other adults he ob- tained the same results (O'S— 0-9 grm. per day). Loebe t obtained a similar average (0-839 grm. per day) from ten ob- servations upon two men. K. B. HofmannJ found in twenty- seven observations upon himself as the daily average 0-681 grm. (max. = 0-810, min. = 0-519 grm.). In other persons he found somewhat more : mean = 0-99 grm. per day. The urine of infants (nursing) contains no kreatinin. Women eliminate somewhat less than men. The daily average in women (of seven observations) was 0-65 grm. The kreatinin of the urine originates from the kreatin of the muscles, which, before it has left the body (probably in the * Annal. d. Chem. u. Pharmac, Bd. 119, page 27, et seq. f Journ. f. prakt. Chemie, 1860, page 170, et seq. jvirchow's ArcMv, 1869, Bd. 48, page 358, et seq. Digitized by Microsoft® 516 SEMIOLOGY OF HUMAN URINE. kidneys), is changed into kreatiain. The muscular tissue of the meat which is eaten partly contributes to this, and partly the muscles of the body, when they are decomposed by meta- morphosis. An increased muscular activity, when not accom- panied by a chemical decomposition of the muscular tissue, produces no increased elimination of kreatinin, as Nawrocke,* Voit,t and Meissner % have shown. Hofmann found that the amount of kreatinin in the urine diminished during starvation. It was considerably increased by a meat diet even in children, who otherwise eliminated little or no kreatinin with the urine. Bodily activity, on the con- trary, had no influence upon the amount of kreatinin. We must consider also the increase or diminution in the elimination of kreatinin with the urine in pathologmil cases. In this respect the facts hitherto obtained teach us the follow- ing : Munk found the kreatinin increased in the urine in acute diseases, like pneumonia, the efflorescent stage of typhoid, and intermittent fever, and diminished during convalescence from acute diseases. Hofmann came to the following conclusions: Purely local aff'ections were without influence ; febrile diseases produced an increase (at the expense of the muscular tissue of the body) ; diseases attended with scanty nourishment pro- duced a diminution. In advanced degeneration of the kidneys the amount of kreatinin in the urine diminished even when an abundance of meat was eaten (probably because the kidneys were unable to change the kreatin present in the blood into kreatinin). H. Senator § found it considerably diminished in the urine in two cases of tetanus — a disease in which, however, there is an excessive activity of the muscles. This fact, which is according to the earlier opinions an apparent paradox, finds its explanation in the above-mentioned experience of Voit and others. Whether there is an increased elimination of kreatinin or not in trichinosis, as would be expected, must be decided by further investigations. Leucin (see § 36) and tyrosin (see § 37, § 48, and page 425) *Centralbl. f. d. med. Wissensch., 1866, page 635. t Zeitsch. f. Biologie, Bd. 4, page 114, et seq. JZeitsch. f. ration. Medic, 1868, Bd. 31, p. 334, et seq. § Ueber die BesobafEenheit des Harnes im Tetanus. Virchow's Aichiv, Bd. 48. Digitized by Microsoft® QUANTITATIVE CHANGES IN TEE UBINE. Qyi ■usually occur together. They are the products of the decom- position of nitrogenous substances, and are, therefore, found in parts of the body which have been preserved for a long time in alcohol, whereby the tyrosin which is insoluble in alcohol separates in the form of a white deposit. When the metamorphosis is normal, they form in the body in, at the most, small amounts ; but when there is an abnormal, putrefac- tion-like decomposition (gangrene, etc.), they form in larger quantity. In such cases they may also pass over into the urine, and their importance for the physician rests upon this, that from their abundant presence in the urine we may infer the existence of such an abnormal decomposition within the organism. They take the place of the diminished, or even ab- sent, urea (compare page 478). Up to the present time they have been found especially in acute atrophy of the liver and in acute phosphorus poisoning, and in a few cases of leucocy- thsemia, typhoid, small-pox, etc.* The presence of aUantoin in the urine has, up to the present time, but slight importance for the physician. It has been found by Frerichs and Stadeler in the urine of dogs when the respiration has been impeded; also by Kohler.t SchottinJ found it in the urine of men also after taking tannic acid. The presence of lactic add (§ 30) and oxymandd acid (§ 38) in the urine of persons suffering with acute atrophy of the liver, need only be mentioned here. A. Ewald § has in a number of cases of persons suffering with acute diseases determined the amount of carbonic acid in the urine, and has found that it is regularly higher during the febrile stage than when there is no fever. The quantitative estimations of albumen and sugar, which are sometimes necessary, have been already treated in § 97 and §104. * Compare Frerichs and Stadeler in Mailer's Archiv f. Anat. nnd Physiol., 1854, page 393, et seq. Schmeissner, Archiv d. Pharmac, October, 1849, Bd. 150, page 11. O. Schultzen und L. Kiess, Ueber akute Phosphorvergiftung u. Leberatrophie, Berlin, 1869. fDe allantoini in nrina impedita respiratione praesentia. Diss. Hal ens, 1857. JLehmann's Hdbch. d. physiol. Chemie, 1859, page 93. § Ueber den Kohlensauregehalt des Hams, Archiv von Reichert und DuBois- Eaymond, 1873. Digitized by Microsoft® 528 semiologt of human ubink % 134. Concluding Observations. The attempt lias been made above to explain the importance of the quantitative changes of the urine for the physician, in such a way as to include the semiology and significance of the different diseases. But the information, Avhich the physician may obtain from the observation of the urine in disease, has by no means been exhausted. He is enabled to draw still more important conclusions in reference to diagnosis, progno- sis, and treatment than the single changes in the urine war- rant in themselves by observing various changes which are present simultaneously or follow each other closely, or even by going a step farther and comparing these with abnormities in other secretions, as the intestinal, the lung exhalations, the perspiration, etc., which give him information as to the general metamorphosis in the organism. It is not my intention to go any farther into this domain, which is still enveloped in dark- ness, and has, for the most part, only recently been investigated. I wish only to give a few cases from which the physician can draw important inferences, and with relatively little trouble.. The following cases have all been taken from real life, and have been observed by me in the manner to be described. In order to avoid being tedious, I only give a sketch of them, bringing out the principal features, and adding a few general observa- tions, where necessary for an explanation : 1. A girl, 20 years old, who had been ailing for a long time and suffering with indefinite symptoms, which were considered to be due to beginning pulmonary tuberculosis, had great thirst, diminished perspiration, and no fever. She passed a very large amount of urine (3,000 to 6,600 cc. daily) of high specific gravity (1'025 to 1'034), and it contained a considerable amount of sugar. The diagnosis was without any doubt dia- betes mellitus. After the use of an animal diet, meat and gluten bread, together with the administration of alkalies (mag- nesia and bicarbonate of sodium) and opium, improvement took place, but it was not of long duration. An intervening pneu- monia fulminans quickly proved fatal. In contrast to this case of decided diabetes mellitus, the author has during the last year Observed a large number of cases in which the urine has contained sugar, usually tempo- Digitized by Microsoft® QUANTITATIVE CHANGES IN TEE URINE. gig rarily and after the ingestion of smaller or larger amounts of sugar, without the general health being disturbed thereby to any great extent. This occurred usually in men of advanced life (although there were a few cases in women) who lived well and suffered more or less with symptoms of arthritis (rich man's gout, podagra, etc.). In some of these cases the urine contained, together with the sugar, considerable quantities of albumen also. Some of these patients the author has had under his observa- tion and treated (usually with slight attacks) for a long time (ten years and more), without having seen any dangerous com- plications occur, or even with only a slight disturbance of the general health. Possibly this report may serve to give consolation to those patients to whom the fear brings more danger than the disease, itself : that glycosuria is not in all cases dangerous. 2. A woman, 36 years old, with a puffy, pale, anaemic loot,, and blue rings about the eyes, suffered with all sorts of nervous symptoms (mental hypersesthesia with a tendency to spasms),, such as are ordinarily included under the name of "hysteria." A more accurate examination showed that the amount of urine passed was very much increased (between 3,000 and 4,000 cc). The urine was pale yellow to bright yellow, its coloring matters; were rather diminished than increased (3 to 5) ; it was only feebly acid, even frequently alkaline, and the free acid was decided- ly diminished (0 to 0-5). Its specific gravity was below the normal (1"012 to 1"015), but the amount of the solid constituents was decidedly increased (80 to 120). This increase included . most of the urinary constituents (urea 40 to 49, chlorine 20 to 30, phosphoric acid 5 to 9, and sulphuric acid 3 to 5 grm.). The urine contained no trace of sugar. Diagnosis : diabetes insipidus. The patient obviously suffered from an abnormal increase of the metamorphosis of tissue (only that of the blood globule being decidedly diminished, and the temperature was also below the normal), the emunctories of the body were almost all increased, and since the patient lived in poor circum- stances, this increased elimination could not be made up by an abundant ingestion of food, so that her nutrition rapidly fell : she lost in weight about three pounds in two days. With an abundant amount of concentrated food combined with tonics (preparations of quinine and iron) and opium, the secretion of Digitized by Microsoft® 520 SEMIOLOGY OF HUMAN URINE. urine gradually became normal, tlie appearance of the patient improved, her strength increased, and the nervous symptoms disappeared. Since, however, the patient returned to her for- mer way of living, the attacks were repeated — diabetes insipidus intermittens. I have frequently observed exactly analogous cases in conse- quence of drinking an excessive amount of water after the care- less employment of water cures, undertaken in consequence of false indications or continued for too long a time. 3. A strong man, ih consequence of exposure to cold, was seized with severe tearing pains in the region of the neck and shoulder (rheumatismus nuchse). The skin became cool and dry, and the amount of perspiration diminished; his urine, how- ever, was increased (3,000 to 4,000 cc). The amount of coloring matter in it was about normal (4 to 5), and also that of the free acid (1-8 to 2-3). Its specific gravity, however, was far below the normal (1-006 to 1-008), and the amount of the total solid con- stituents was rather diminished (36 to 40 grm.), also that of the individual substances, the urea, chlorine, phosphoric acid, and sulphuric acid was rather below than above the normal. Diag- nosis : hydruria. The increase of the urine was evidently only dependent upon an increased elimination of water by the kid- neys, which made up for the diminished separation of water by the skin and lungs. Although the hydruria continued for several days, yet the strength and weight of the patient did not diminish. After treatment with diaphoretics, which pro- duced an increase of the perspiration, the polyuria gradually disappeared, and also, after the use of wet cups, the rheuma- tismus nuchas. 4. In the case of a young man with organic heart disease (in- sufficiency of the bicuspid valve with consequent hypertrophy and dilatation of the right ventricle), the amount of urine gradu- ally diminished (from 1,600 to 1,200, 800, and 600 cc.) ; at the same time the elimination of the urea (26, 20, 18 grm.) and chlorine (8, 5, 3, grm.) diminished considerably, and to a less extent that of the phosphoric acid (2 to 1-5 grm.) and sulphuric acid (1-5 to 1 grm.). Dropsical effusion into the abdominal cavity and oedematous swelling of the extremities, especially the lower, followed. After the administration of powerful diure- tics (infusion of digitalis and acetate of potassium) the amount Digitized by Microsoft® QUANTITATIVE OHANGES IN THE URINE. 521 of urine increased considerably (3,000, 4,000, 4,500 cc), and with this very considerable amounts of urea (50, 55, 60 grm.) and chlorine (25, 30, 33 grm.) were eliminated, while the sulphuric and phosphoric acids scarcely exceeded the normal amount. In this case evidently large quantities of water, urea, and chlo- riae, instead of being evacuated with the urine, had gone over into the dropsical effusions and had accumulated in them, and after the abundant diuresis were separated with the urine. The same course, diminution of the secretion of urine, and simultaneous dropsical swellings with an increased elimination ■of water, urea, and chlorine with the Urine after the use of ■diuretics, was repeated several times afterward in the same ■case. 5. An elderly man, who suffered with a very marked rigidity of the arteries, was attacked with a pretty severe bronchitis, extending over both lungs. The condition of the patient was subject to extraordinary variations ; violent attacks of dyspnoea with a small rapid pulse of 100 to 126 beats, which sometimes caused fainting, alternated with a tolerable condition. The ex- amination of the urine showed that there were similar variations in the metamorphosis of tissue, which ran a parallel course with the general condition of the patient. On some days only 300 or 400 cc. of urine were passed, and on others 1,200 to 1,500 cc. Its color varied from bright yellow to red ; the coloring matter, from 2 to 18, was, however, as a rule, increased (influence of the fever) ; the specific gravity was about the average (1'012 to 1"023), the amount of solid constituents was, ^n the average, far below the normal (18 to 30 grm.), the amount of urea was also very varying, but was also, in spite of the fever, far below the normal (12 to 25 grm.) ; the urine frequently contained a sedi- ment of urates. The chlorine showed the greatest variation ; it was always considerably diminished, and sometimes only traces were found in the urine (0*1 to 5 grm.). The phosphoric and sulphuric acids were also diminished. These considerable variations in the metamorphosis of the patient, depending upon a shattered constitution, taken in connection with the existing lung disease, led to the fear of a speedy collapse. In fact this took place very suddenly. On one evening after the patient felt better and more brisk than usual, he complained of great weakness in the night, and a rapidly spreading oedema of the Digitized by Microsoft® 522 SEMIOLOGY OF HUMAN URINE. lungs, which withstood all counter-irritants used, proved fata! in a few hours. 6. A man, 57 years old, in consequence of a severe exposure to cold upon a journey, was attacked with a pneumonia of the left side, which was, from the beginning, treated with cupping and digitalis in large doses {\ drachm daily). The patient had very severe fever ; the urine was less scanty than in other simi- lar cases (at the height of the disease, 900, 1,000, 1,950, 1,500, 1,350, and 1,200 cc), very high colored, the amount of coloring matter considerably increased (28 to 32), the specific gravity about normal (1-018 to 1-024:), and the solid constituents usually below but sometimes above the normal. The urea was increased (40 to 60 grm.), the sulphuric acid at first increased (3-5 to 4 grm.), but later was below the normal (1-8 — 1-1 — 1*6 grm.), and the phosphoric acid was almost always increased (4 — 5 — 7 — 8 grm.). The chlorine, during the first two days, was present only in traces, increased gradually (3 — 4 — 7 grm.), and reached the normal from the eighth day. The patient improved very rapidly in spite of his advanced age, and in spite of the fact that he had previously had pneumomia, so that his lungs were pro- bably not entirely normal, and was able to leave the hospital well in ten days. This case is especially interesting in refer- ence to the metamorphosis, since it shows the favorable action of the digitalis. There was in this case, as in all violent fevers, an increased decomposition of the constituents of the body, and unusually large quantities of urea and urinary coloring matter were formed, an^ increased amounts of phosphoric and sul- phuric acids were set free from their organic compounds. But the secretion of urine was, in this case, oving no doubt to the influence of the digitalis, much more abundant than in other similar cases, whereby the decomposition products formed were quickly separated from the body, and convalescence hastened. I do not mean to say that the action of digitalis in such cases is limited to this efi'ect, but only mention that method of action as an apparent one in this case. 7. A man sufi'ered with a chronic affection of the liver and stomach with organic change which could be ascertained, al- though its exact nature could not be diagnosticated. Long-con- tinued disturbances of digestion and severe pain had exhausted his strength, and, therefore, it was desirable to obtain a nearer Digitized by Microsoft® qXTANTITATIVE GHANOES IN THE UBINE. 533 insiglit into the metamorphosis of the patient, partly to establish the indication for the means to be first used for the symptoms, and partly for the purpose of giving a prognosis. !For this reason the patient's urine was examined for several days in suc- cession, and the following were obtained as the average propor- tions : The quantity was about normal (1,500 cc), the color bright yellow, the coloring matter somewhat below the normal (3), the reaction feebly acid, and the free acid considerably di- minished (0"4). The specific gravity was somewhat low (1'014), and also the solid constituents (42 grm.) ; of the single consti- tuents, the urea (29 grm.) and sulphuric acid (1'4 grm.) were somewhat diminished, while the phosphoric acid (3'3 grm.) was about normal, and the chlorine (10 grm.) was rather in excess of the normal. This showed at that time a good condition of the digestion (chlorine and PO5 abundant), but, on the contrary, a somewhat diminished decomposition of the nitrogenous tis- sues (urea and SO3 below the normal), and also a diminished metamorphosis of the blood globule (small amount of pigment and considerable diminution of the free acid). The last part of the diagnosis was confirmed by the pale anaemic appearance of the patient. In consequence of this information the patient received a good diet, with tonic drugs, whereby his strength and vital energies were, for a time at least, increased, although the complete cure of the organic changes forming the principal trouble could not be expected. 8. There are cases in which a febrile increase of the meta- morphosis can be recognized almost solely by the composition of the urine. The pulse is entirely quiet, the temperature of the external parts of the body scarcely increased, the appetite but little diminished, and yet there exists an increased tendency to the decomposition of the constituents of the body and a ces- sation of the excretory activity of the kidneys, a condition which may be especially dangerous when, with an existing disease of an important internal organ, like the lungs, liver, etc., it gives rise to congestion of this organ, which, if long continued, easily leads to organic changes or increases any such already present. The following is a case of this kind. A very powerful man, 48 years old, with a broad, full chest, came with symptoms which pointed to a commencing pulmo- nary tuberculosis. He had for a long time had a cough with Digitized by Microsoft® 524 BEMIOLOGT OF HUMAN URINE. expectoration, slight dulness of percussion over the apex of the right lung, with ill-defined, almost bronchial, respiration and rales at this point. His respiratory power was less than corre- sponded to the size of his body ; fulness of body and strength had diminished somewhat during the last month. His pulse was, however, entirely quiet (60 to 63), his appetite was tolera- bly good (^ diet with various extra dishes), the temperature of the extremities was not increased, and only in the night there was sometimes profuse perspiration. The urine, on the contrary, was remarkably abnormal ; it was very much dimin- ished (400 to 600 CO.), almost always turbid, with a sediment of uric acid ; very high colored, and the coloring matter increased (16 to 24) ; the specific gravity was very high (1-022 to 1-028), the urea was rather above the average (28 to 35 grm.), the chlo- rine very much diminished (3 to 5 grm.), and the phosphoric acid (2-5 grm.) and sulphuric acid (1-6 grm.) were somewhat below the normal. The excretory activity of the kidneys was, therefore, decidedly diminished, and since at the same time the decomposition of the constituents of the body was in- creased, the blood was overcharged with irritating ingredi- ents. It happened that the patient had for a long time pre- viously suffered with a chronic skin disease (probably psori- asis), which had disappeared six months before. There existed here, therefore, several conditions together, which must have caused an excessive activity of the lungs, and thereby an in- crease of the disorganization to be expected in them. (An ac- curate examination revealed, in spite of the slow and quiet arterial pulse, an increased activity of the right ventricle of the heart and an evident strengthening of the pulmonic second sound, an overloading of the lungs with blood : at the same time the patient complained of considerable dyspnoea and tightness of the chest.) The principal indication appeared to be to free the lungs of the patient from the irritation caused by the accumulation of excrementitious substances in the blood by increasing the secretion of urine. He was given mild diu- retics and blood-purifying drugs (infusion of digitalis with ace- tate of potassium ; a tea of the viola tricolor). In general, as the secretion of urine increased, the patient felt freer in the chest, and much more comfortable in his general condition, so that, after a while, he was able to be discharged much improved. Digitized by Microsoft® qUANTITATIVE CHANGES IN THE URINE. 535 Since, however, he could not and would not pursue a desirable mode of living outside of the hospital, and, moreover, was an excessive spirit drinker, the disease made new progress, and lie returned to the clinic after six months with settled pulmo- nary tuberculosis, and died there a few days later. 9. A man, 45 years old, was attacked suddenly with all of the symptoms of a violent febrile disease : chills and heat, loss of appetite and bloody urine. Within one and a half days an cedematous swelling spread over the whole body with the ex-, ception of the face. When the patient was admitted a few days later into the clinic at Gie^sen, the symptoms were the same as those given except with the addition of violent vomiting. During the first three days of his stay there the urine had the following appearances : Its amount was somewhat below the normal (900 to 1,500 cc), and its color intense blood-red. Under the microscope it was seen to contain unchanged blood cor- puscles in considerable quantity, numerous pus corpuscles, and a few granular casts. It contained an abundance of albumen. The reaction was alkaline, the specific gravity was low (I'OIO to 1'012), the amount of urea was far below the normal (8 to 20 grm.), the chlorine was considerably diminished (1 to 3 grm.), the phosphoric acid somewhat (1'3 to 2'8 grm.) and the sul- phuric acid considerably (0"5 to 1"6 grm.) diminished. On long standing, a slimy sediment formed in the urine, due to the ac- tion of the ammonia upon the pus corpuscles suspended in it. The perspiration (sum of the evaporation from the skin and the lung exhalation) was far below the normal (460 to 780 grm. in twenty-four hours), the ingesta considerably exceeded the ex- creta, so that the patient increased in weight ten pounds in three days, which naturally was due only to the constantly in- creasing dropsical swelling. Diagnosis : Morbus Brightii acu- tus. On account of the great danger that uraemia might de- velop suddenly under such circumstances, the most powerful means were employed to increase the secretion of the kidneys and bowels, but without effect. All remedies taken internally (sulphate of sodium with acetate of potassium, gamboge with carbonate of sodium, croton oil) were vomited again by the pa- tient ; applications of decoction of digitalis made over the whole body remained without effect ; enemeta of croton oil dissolved in Linseed oil irritated the rectum to such an extent that it was Digitized by Microsoft® 526 SEMIOLOGY OF HUMAN UBINE. necessary to omit them. Tlie excretory activity of the kid- neys diminished daily ; the amount of urine fell from 800 to 700, 500, and 450 cc. daily, having a specific gravity of from 1-015 to I'OIO. The amount of urea diminished continuously (6 to 8 grm. daily), also the chlorine (0-8 to 1 grm.), sulphuric, acid (04 to 0-6 grm.), and phosphoric acid (1-3 to 1-7 grm.). Symptoms of ursemia (vertigo, delirium) developed, which con- tinued to increase (coma vigil, sopor) till the patient died, scarcely three weeks from the commencement of his disease. The section showed the existence of two stages of Bright's disease in the kidneys. 10. A man, 52 years old, of strong physical constitution, was attacked with acute Bright's disease, exactly as in the above case. Considerable oedematous swelling of the whole body, followed quickly by violent febrile symptoms : the blood- red urine was rich in albumen and showed under the micro- scope the presence of traces of renal casts together with numerous blood and pus corpuscles. But in this case power- ful diuretics (pills of gamboge and carbonate of sodium, and especially applications of the decoction of digitalis which were made on a large scale over the whole lower half of the body) succeeded in producing an abundant secretion of urine. The urine (from the 25th of October to the 1st of November) had the following properties : The amount was very much in- creased (4,800 to 6,800 cc), the color was red (bloody), the reaction neutral or alkaline, the specific gravity low (1"003 to 1"005), the urea increased (between 45 and 97 grm. daily), also the chlorine (20 to 30 grm.), phosphoric acid (11 to 18 grm.), and sulphuric acid (41 to 4-7 grm.). With this increase in the secretion of urine the dropsical swelling disappeared entirely, the symptoms of ursemia (wandering, somnolence) which ap- peared at first ceased, and the patient felt very well. After a while a fresh exacerbation came on : violent fever with swell- ing of the lips and a phlyctsenoid eruption about the mouth, more scanty and very bloody urine. Since the last symptom showed a violent inflammation of the kidneys and there was no dropsy, diuretics appeared to be no longer indicated, and I considered the principal indication to be now to act upon the kidneys with remedies to lessen the inflammation. An emulsion of oannabis-indica seeds with bitter-almond water was given, Digitized by Microsoft® qXTANTITATIVSl CEANQES IN THE URINE. 537 and after two days the deep bloody urine became almost color- less. 11. Hcematuria, caused by dissolved hcemoglobin. (Compare § 100.) A young man, 20 years old, always well up to tlie present time, complained that he had not felt well for about eight days. His face was extremely pale, livid in spots, espe- cially under the eyes, where there were bluish-red rings ; the temperature of the skin was not increased, the pulse was rapid (90 to 100), small, and feeble. There were mild, tearing, draw- ing pains over the greater portion of the body, especially the ■extremities, together with a sensation of weariness and depres- sion. There was also a mild catarrh of the organs of respira- tion and digestion (loss of appetite, coated tongue, moderate diarrhoea), and slight increase in the size of the spleen. He was received into the clinic, and it was suspected that a ty- phoid fever was coming on. This suspicion, however, was not realized. The mild febrile symptoms diminished rather than increased, the very feeble, often dicrotic, pulse became slower and fuller, the temperature did not rise above the normal, but usually remained below 37° C, the intellect remained clear, while the patient became so weak that he could scarcely raise himself, and the anaemic livid appearance was so extreme that it reminded one of the algid stage of cholera. The urine was of normal amount, and dark brownish-red color (between 7 and 8 in the color table), similar to, although not quite as dark as, specimens which I have seen after the inhalation of arseni- uretted hydrogen. (See page 392.) It contained at least 300 parts of pigment. No blood corpuscles, and in general, no morphological elements could be detected under the micro- scope. Upon boiling, a very abundant reddish-brown coagulum of haemoglobin was formed, the filtrate from which had a feeble yellow color. Otherwise it contained the ordinary constituents in normal amount, only the chlorides being somewhat dimin- ished on account of the scanty diet. This condition of the urine, which had certainly existed before the admission of the patient (he could give no explanation of it), lasted about eight days and then disappeared gradually. It indicated that the disease consisted essentially of a continued extensive decom- position of the blood globules within the blood vessels, the products of which were eliminated with the urine (perhaps Digitized by Microsoft® 528 SEMIOLOGT OF HUMAN URINE. partly, also, witli the bile), and wMcli by its intensity and long duration produced an oligocytlisemia of high grade. The con- dition of the urine together with the great depression and the pains in the limbs pointed also to scorbutus, but the change in the gums as well as the ecchymoses into the skin and subcu- taneous cellular tissue, etc., were absent, and also any etiologi- cal fact which could play any part in the production of scor- butus. The patient took mineral acids, at first alone, but later with quinine, and during convalescence preparations of iron. He recovered slowly but completely. No cause could be discovered. A few months later, without any cause which could be de- tected, another attack of hsematuria appeared, only shorter and less intense than the former one. During this attack, as during the first one, the patient was entirely free from pain in any part of the uropoetic system. 12. The following case, essentially different from the pre- ceding one, and also occurring without any discoverable cause, affords an example of vesical hcEmrduria. Friedrich P., but- cher, 22 years old, never sick before, born of healthy parents ■ (the father is said to have suffered from haemorrhoids only),, was attacked with a mild gastritis with dizziness and ring- ing in the ears, and was on that account admitted into the clinic. Formerly he had never had attacks of hemorrhage^ but a few years before his sickness he had frequently had nose-bleed. A more accurate examination of the patient showed that his urine was blood red, and a further investiga- tion showed that he suffered with dysuria, a frequent involun- tary impulse and desire to urinate, so that he was forced to mic- turate almost every quarter of an hour. The urine, especially that . last evacuated, was always very bloody. Examination of the orifice of the urethra showed nothing abnormal, the poste- rior part of the urethra was not tender on pressure, nor did the digital examination, per anum, of the prostate and bladder show any abnormity. The plainly bloody-colored urine depos- ited after long standing a scanty dark-red sediment, which be- came diffused upon shaking and which consisted only of blood corpuscles without admixture with pus. If the urine was fil- tered, the filtrate appeared to be completely free from blood,. Digitized by Microsoft® qUAN'TITATlTE GEAN&ES IN TEE UHmE. 539 of a clear yellow color, while a dark-red precipitate of blood corpuscles remained behind on the filter ; the urine contained, therefore, only undecomposed blood globules and no dissolved blood pigment. The blood corpuscles came without doubt from the bladder, and the cause of their passage into the urine was probably a congestive hypersemia of the mucous mem- brane of the bladder, which had increased to such an extent as to rupture the vessels. The treatment was limited to the administration of hemp- seed tea with bitter-almond water, under which the patient im- proved so much that the dysuria disappeared in a few days, and the blood gradually ceased to appear. 13. The following case is interesting since it resembled most delusively a case of hsematuria, the non-existence of which was only recognized by the microscope. An old man, 72 years old, had had for about five years an affec- tion of the bladder, which was chiefly, characterized by the fact that the patient, who had previously been well and was for his age very robust, from time to time after straining, too long re- tention, etc., passed a little blood with his urine, and had slight pain in the region of the bladder. The simultaneous occasional evacuation of gravel had given rise to the suspicion that a vesi-. cal calculus might exist. He had, therefore, consulted various physicians and had been examined several times, but no calcu- lus had been detected. Most of the physicians explained his affection by the existence of bladder hsBmorrhoids, and the pa- tient had in consequence used Kissingen and Carlsbad waters without any marked benefit. He had never lost blood with his stools. Examination showed no trace of haemorrhoids and no enlargement of the prostate. His general health was good and his arteries were not rigid. The urine of the patient was very strongly acid and deposited a sediment of large crystalline masses of uric acid. There was, besides, a very abundant dirty-red (cinnamon colored) sediment, in which there were large flocculi and which settled pretty^ quickly. Disseminated through the urine it gave it the appear- ance of being mixed with blood, and it had been so considered by the patient and his various physicians up to this time. Under the microscope numerous cellular forms were seen, which at first sight appeared to be blood globules, but which upon 34 Digitized by Microsoft® 530 BEMIOLOaT OF HUMAN UBINE. more careful examination were seen to differ from them in im- portant particulars. They were round and reddish colored like blood globules, but were somewhat larger (-jJu to ^h'" ^^