LIST OF ILLUSTRATIONS. 



PLATES. Fadng 



Page. 

 Plate 1. a, c, and e, thin sections taken from potters' cells, b, d, and /, thin sections taken 



from cells made in the laboratory 16 



Plate 2. View of "manometer house," cathetometer, arrangement for pressing clays, and 



one style of rectangular bath 42 



Plate 3. View of circular and rectangular laboratory baths in use 6S 



Plate 4. Rectangular bath, end view 70 



Plate 5. Rectangular bath, side view 72 



TEXT FIGURES. 



Page. 



1. Steel press for clays. Ball-bearing disk 8 



2. Apparatus for pressing clays 10 



3. Clay cylinder after pressing. Clay cell after shaping the cylinder on the lathe 11 



4. Different views of special tool for cutting cell from cylinder 12 



5. Electric kiln for baking cells. Inner and outer coverings for electric kiln 14 



6. Electric kiln arranged as crucible furnace 14 



7. First form of complete cell 19 



8. "Fang" for introduction and removal of rubber stoppers 18 



9. Second form of complete cell 19 



10. Third form of complete cell 22 



11. Fourth form of complete cell 22 



12. Fifth form of complete cell; for use with substances which attack metals 23 



13. Solid glass stopper for use with substances which attack metals 25 



14. 15. Glass manometer attachments for cells with straight necks 25 



16. First arrangement for calibrating manometers 30 



17. Second arrangement for calibrating manometers 31 



18. Simplest form of manometer 32 



19. Manometer for high pressure 32 



20. Manometer with glass cone for cells with taper necks 36 



21. Manometer with glass connection for cells with straight necks 38 



22. "Steel block" for determination of gas volumes in manometers, for comparison of 



instruments, and for determination of capillary depression 40 



23. Electric hammer for tapping manometers 41 



24. "Manometer house" for calibration and comparison of instruments, etc 43 



25. Improvement in cathetometers for the fine adjustment of the telescope, which also 



serves as a substitute for the micrometer eye-piece 44 



26. Arrangement for filling manometers with nitrogen 46 



27. "Brass block" 49 



28. Apparatus used in emptying, filling, and cleansing the uncalibrated portion of the 



manometers 50 



29. General scheme for the electric regulation of bath temperature 58 



30. The thermostat 60 



31. Interior ice-bath for measurement of osmotic pressure at 0° 62 



32. 60-liter galvanized-iron bath for intermittent use 63 



33. Coil of block-tin pipe for cooling or heating water before it enters the circulating system 



within the bath 66 



34. Rectangular bath for general laboratory use 67 



35. 36. Lower and upper halves of rectangular bath for measuring osmotic pressure 69 



37. Hot-water circulating system with end of bath removed 70 



38, 39. Brass and copper bath for high temperature work 72 



40. Brass-copper bath for high temperatures 73 



41. Exterior view of bath for high temperatures 74 



42. View between interior and exterior baths, i. e., of space filled with water 74 



43. Automatic arrangements for maintaining temperature of upper door when open 75 



44. Larger (elliptical) bath for high temperatures 75 



45. Exterior view of larger bath for high temperatures 76 



46. First bath employed for measurement of osmotic pressure 114 



47. First bath in which water and air were circulated 119 



48. Pumping arrangements on larger scale than in figure 47 120 



49. Interior view of water compartment with covers partly removed 121 



v 



