Figures Page 



55. Gear Modification of Brush Recorder Chart Drive to furnish 



chart speeds of 1.25, 6.25, or 31.25 mm per second . . . 106 



56. Gear Modification of Brush Recorder Chart Drive to 



furnish chart speeds of 1.0, 5.0, 25.0 mm per second . . 107 



57. Gear Train Brush Recorder prior to modification 109 



58. Gear Train Brush Recorder after Modification 110 



59. Sample Wave-period Template 112 



60. Sample of Wave-height Template 113 



61. Sample of Wave-height Template ........ 114 



62. Wave-data Compilation Sheet 115 



63. Pressure Response Curves for Various Depths and Wave 



Periods 116 



VII 



