728 DR. OLIVER LODGE ON ABERRATION PROBLEMS. 
Page. 
Section 29. ' Moving matter, on Feesnel’s hypotLesis, does not disturb the ether of space . 752 
30. No first-order experimental result yet obtained can discriminate bet-ween com¬ 
plete connection and complete independence of ether. 752 
31. Question ■whether purely irrotational motion is possible in a medium through 
which planets move. 753 
32. Viscous motion must curve rays and cause a real or negative aberration . . 754 
Experimental Portion. 
33-46. Details of apparatus made to examine into the velocity of light near moving 
matter; and experiments tending to the conclusion that the ether is not 
connected to matter by anything resembling viscosity. 754r-76 
47. Future experiments. The effect of moving air is too small for observation 
so far. 778 
More detailed consideration of Aberrational Effects in Moving Medium. 
48. Change of entme medium changes aberration constant. 779 
49. Motion of entire medium has a second-order effect on aberration. 779 
50. Change of a part of the medium does not appreciably modify abeiration 
effects. 780 
51. Connection of this with Fresnel’s law. 781 
52. Motion of a part of the medium does cause aberrational effects. 782 
More detailed consideration of Eoppler Effects. 
63. Differences between moving source and mo'ving receiver. 782 
54. Steady motion of medium causes no Doppler effect. 784 
55. But is able to modify one otherwise caused. 785 
56. The apparent change of wave-length observed by a moving grating is really 
an aberrational effect, due to motion of observer partly across the line of 
sight. 786 
57. The same is true for observation made with a moving prism. In both cases 
dispersion depends really on wave-length, apparently on frequency . . . 788 
68. Dispersive power due to motion. 789 
More detailed consideration of Michelson Experiment or Interference Effects in Moving Medium. 
59. Geometrical treatment of the reversal of a ray on itself in any azimuth with 
respect to the motion of source . 789 
60. Another treatment, with medium moving. 791 
61. Effect of the glass lenses and slabs used by Michelson. 791 
62. Effect of a completely different medium. 792 
The Lazes of Reflexion azid Refraction in a Moving Medium. 
63. General considerations. 793 
64. Summary of results. 794 
65. Warning against possible errors. 795 
66. Reflexion in a mo-ving medium. 795 
67. Effect of drift on zvaves, and on width of beam. 797 
