6 CONTENTS. 



46. Direct telephonic induction. Figs . 70, 71, 72, 73, 74 .......................... 64 



47. Narrow bifilar ............................................................ 67 



48. The vibratory stray magnetic fields ......................................... 68 



49. Resistance, capacity inductance in case of the compensated vibrator. Figs. 75, 



76, 77, 78 ................. ............................................ 69 



50. Ring transformer ......................................................... 72 



51. Magnetic screens ......................................................... 72 



52. Amplitude of the interrupter ............................................... 73 



53. Telephones in parallel ..................................................... 73 



CHAPTER VII. Self-adjusting Interferometer in Relation to the Achromatic 



Fringes and Refraction. 



54. Introductory. Fig. 79 .................................................... 74 



55. Character of the achromatic fringes. Fig. 80 ................................ 75 



56. Curvilinear compensators. Fig. 81 ......................................... 77 



57. Index of refraction, irrespective of form ..................................... 78 



58. The same. Glass plate. Lenses. Figs. 82, 83, 84 ............................ 78 



59. Adjustable compensators. Fig. 85 .......................................... 79 



60. Observations of refraction ................................................. 80 



61 . Equations and data. Table 6 .............................................. 81 



62. Micrometer measurements. Table 7 ........................................ 85 



63. Summary ............................................................... 86 



CHAPTER VIII. An Adjustment in Relation to the Fresnel Coefficient. 



64. Apparatus. One internal reflection. Figs. 86, 87, 88 ......................... 88 



65. Apparatus. Two internal reflections. Fig. 89 ............................... 89 



66. Equations. One internal reflection. Figs. 90, 91 ............................. 90 



67. Equations. Two reflections ................................................ 92 



68. Experiments. Figs. 92, 93 .................... . ........ ........ ............ 93 



69. Modification of the experimental design. Rotating, self-adjusting interferometer. 



Fig. 94 ............................................................... 95 



CHAPTER IX. Sharp Spectrum Fringes With an Indefinitely Wide Slit, including 

 the Superposition of Fringes Due to the Color and to the Obliquity of Rays. 



70. Introductory ............................................................. 96 



71 . Apparatus. Fig. 95 ...................................................... 96 



72. Equations ............................................................... 97 



73. Observations. Figs. 96, 97, 98, 99 ......................................... 98 



74. Summary ............................................................... 99 



75. Reversed spectra ......................................................... 100 



76. The same, continued ...................................................... IOC 



77. Monochromator. Figs. 100, 101 ........................................... 101 



78. Quartz prism. Fig. 102 ................................................... IO2 



CHAPTER X. Miscellaneous Results of the Preceding Experiments. 



79. Spectrum phenomena due to moving motes. Fig. 103 ........................ 104 



80. Separated Jamin plates. Figs. 104, 105, 106, 107 ....................... ...... 107 



81. Interferometry with aid of secondary and tertiary achromatic satellites. Fig. 108. 109 



82. The triangular self-adjusting interferometer. Fig. 109 ........................ no 



83 . Herschel's fringes. Fig. no ............................................... Hi 



84. The same, continued. Fig. in ............................................ 112 



85. Measurement of small angles by a half -silver plate. Fig. 112 ................... 113 



CHAPTER XL Interferometer Observations and Achromatic Fringes in Connection 



with the Horizontal Pendulum. 



86. Apparatus and data. Fig. 1 13 ............................................. 114 



CHAPTER XII. Gravitational Experiments. 



87. Introductory 



88. Apparatus. Fig. 117 ..................................................... 116 



89. Needle in air. The two methods. Fig. 114. Table 6 ......................... 117 



90. Reversal at symmetrical positions. Figs. 115, 116 ............................ 118 



91. Reversal after equal time intervals. Figs. 1 18, 119 ........................... 119 



92. Static elongation. Table 7 ................................................ 120 



93. Recent work ............................................................. 122 



