xii CONTENTS 



PAGE 



CHAPTER IV. THE COMPOUNDS OF THE PROTEINS 67 



1. The Amphoteric Character of the Proteins 67 



2. The Direct Method of Demonstrating the Existence of Protein 



Compounds by Precipitation or Coagulation 68 



3. The Direct Method of Demonstrating the Existence of Protein 



Compounds by the Solution of otherwise Insoluble Substances. 71 



4. The Indirect Method of Precipitation 71 



5. The Method of Electrical Conductivity 74 



6. The Cryoscopic Method 74 



7. The Potentiometric Method 76 



8. The Method of Catalysis 79 



9. The Indicator Method 81 



10. The Method of "Masking" the Physiological Effects of Ions by 



the Addition of Proteins to their Solutions 82 



CHAPTER V. THE COMPOUNDS OF THE PROTEINS Continued 85 



1. Stoichiometrical Relations in Protein Compounds 85 



2. The Compounds of the Protamines with Inorganic Acids and 



Bases 86 



3. The Compounds of Casein with Bases, Acids, and Salts 88 



4. The Compounds of Serum Globulin with Inorganic Acids and 



Bases 98 



5. The Compounds of Fibrin with Inorganic Acids and Bases 101 



6. The Compounds of the Vegetable Proteins with Inorganic Acids 



and Bases 101 



7. The Compounds of Ovomucoid with Acids and Bases 103 



8. Summary of Some of the Results Cited in this Chapter 103 



CHAPTER VI. THE COMPOUNDS OF THE PROTEINS Continued 107 



1. General Remarks on the Precipitation of the Proteins by Inorganic 



Salts 107 



2. Earlier Investigations on the Significance of the State of Hydra- 



tion of the Proteins in Relation to their Coagulation by Salts. 108 



3. The Influence of the Electrical Condition of the Proteins upon 



their Precipitation and Coagulation by Electrolytes 112 



4. Later Investigations on the Significance of the State of Hydration 



of the Proteins in Relation to their Coagulation by Electro- 

 lytes 119 



5. Application of the Phase-rule to Protein-salt-water Systems 123 



6. The Chemical Mechanics of the Precipitation and Coagulation of 



Proteins by Salts 125 



CHAPTER VII. THE COMPOUNDS OF THE PROTEINS Continued 137 



1. Compounds with the Heavy Metals 137 



2. Compounds with the Phosphoric Acids 142 



3. Compounds of the Proteins with Carbonic Acid 144 



