CONTENTS. 



Part I. General Outline of the Investigation. By Arthur A. Noyes. 



Part II. Original Apparatus and Method. Conductivity and Ionization of 

 Sodium and Potassium Chlorides up to 306. By Arthur A. Noyes and 

 William D. Coolidge. 



1. The conductivity vessel or bomb 9 



2. The conductivity measuring apparatus 11 



3. The heaters 11 



4. Thermometers 13 



5. Details of the construction of the bomb 13 



6. Procedure for the conductivity measurements 23 



7. Procedure for the specific-volume measurements 26 



8. Standardization of the apparatus . . . 27 



9. Preparation of the substances and solutions 30 



10. Discussion of the systematic errors and their correction .... 30 



11. The specific-volume data 35 



12. Summary of the specific-volume values 35 



13. The conductance-capacity of the apparatus 37 



14. The water correction 39 



15. The conductivity data 39 



16. Summary of the equivalent-conductance values reduced to 



round temperatures and concentrations 43 



17. Change of equivalent conductance with the concentration .... 48 



18. Change of the equivalent conductance with the temperature . . 52 



19. Ionization-values and their change with the concentration and 



temperature 54 



20. Summary 53 



Part III. Later Modifications of the Apparatus and Method. By William D. 

 Coolidge. 



21. New material for the shell of the bomb 59 



22. Screw-thread on the steel shell 59 



23. Special lathe-chuck used in the construction of the bomb .... 60 



24. A new composite lining for the bomb 60 



25. A method for removing the lining by hydraulic pressure .... 61 



26. A more delicate leakage test 62 



27. Solid platinum-iridium electrodes 62 



28. Apparatus and method for rotating the bomb in the heaters . . 64 



29. A vapor bath for heating the rotating bomb 66 



30. A liquid bath for the rotating bomb 67 



Part IV. Conductivity and Ionization of Silver Nitrate, Potassium Sulphate, 

 and Barium Nitrate up to 306, and of Magnesium Sulphate up to 218. 

 By Arthur A. Noyes and Arthur C. Melcher. 



31. Outline of the investigation .... 71 



32. Description of the apparatus and method 71 



33. Preparation of the substances and solutions 73 



34. Systematic errors and their elimination 74 



35. The conductance-capacity and the water correction 76 



iii 



