ILLUSTRATIONS. 



PAGE. 



FIG. 1. Bed respiration calorimeter 15 



2. Air-circuit and purifying arrangements of tension-equalizer unit 22 



3. Arrangement of Benedict respiration apparatus (tension-equalizer unit). . . 22 



4. Pneumatic nosepiece 23 



5. Tension-equalizer with three-way valve and mouthpiece 25 



6. Carbon-dioxide absorber and accompanying water-absorber 27 



7. Moistener 29 



8. Apparatus used for tests of respiration apparatus with burning ether 31 



9. Schematic outline of ventilation system of spirometer unit 34 



10. Detailed plan of ventilation system in spirometer unit 35 



11. Cross-section of the three-way valve, ventilating pipe, and connection for 



mouthpiece and moistener 36 



12. Details of moistener and connection for nosepieces 37 



13. Details of spirometer, with recording attachments 38 



14. Specimen graphic record of respiration 40 



15. Bohr meter 41 



16. General view of the spirometer unit 41 



17. Specimen kymograph records in the calibration of the ventilation adder. . . 45 



18. Mouthpiece and valves used in the Zuntz-Geppert apparatus 54 



19. Most recent form of the Zuntz valves 54 



20. Zuntz-Geppert apparatus, showing Elster meter, automatic sampling device, 



and gas-analysis apparatus 56 



21. Caustic potash pipette used in the Zuntz-Geppert analysis apparatus 58 



22. Absorption pipette used in the Zuntz-Geppert analysis apparatus 58 



23. Nosepieces and valves used with the Tissot method 62 



24. Modified glass nosepieces 62 



25. Apparatus for registering the respiration-rate used with the Tissot method . 63 



26. Tissot spirometer with capacity of 50 liters 64 



27. Tissot spirometer with capacity of 200 liters 64 



28. Apparatus for registering the volume of air in the Tissot spirometer 65 



29. Mica-flap valve used with the Douglas method 68 



30. Rubber-flap valve used with the Douglas method 69 



31. Mueller valve 70 



32. Haldane gas-analysis apparatus (laboratory form) 72 



33. Hand spirometer 79 



34. Apparatus used for alcohol check-tests of the Tissot method 80 



35. Type of respiration of subject H. F. T. as shown by chest pneumograph in 



the first period with the bed calorimeter on August 29, 1911 88 



36. Type of respiration of subject H. F. T. in the first period with the bed 



calorimeter on August 31, 1911 89 



37. Probability curves for the series of comparison experiments with the spiro- 



meter unit and the tension-equalizer unit 117 



38. Probability curves for the series of comparison experiments with the tension- 



equalizer unit and the Zuntz-Geppert apparatus 128 



39. Types of respiration of subject H. F. T. in third and sixth periods with the 



spirometer unit on January 18, 1912 130 



40. Types of respiration of subject H. F. T. in first and second periods with the 



spirometer unit on January 30, 1912 131 



41. Types of respiration of subject P. F. J. in the seventh and eighth periods 



with the spirometer unit on February 7, 1912 133 



42. Probability curves for the series of comparison experiments with the spiro- 



meter unit and the Zuntz-Geppert apparatus 143 



43. Probability curves for the series of comparison experiments with the tension- 



equalizer unit and the Tissot apparatus 151 



44. Probability curves for the series of comparison experiments with the spiro- 



meter unit and the Tissot apparatus 161 



5 



