| FIG. | Illustrations of Aberration. |
| 1. | Cannon shots | [35] |
| 2. | Boats or Waves | [36] |
| 3. | Lighthouse beams | [37] |
| 4. | Ray through a moving stratum | [40] |
| 5. | Wave-fronts in moving medium | [41] |
| 6. | Normal reflexion in moving medium | [43] |
| Experiments on Ether drift. |
| 7. | Interference Kaleidoscope | [51] |
| 8. | Hoek's experiment | [53] |
| 9. | Experiment of Mascart and Jamin | [54] |
| 10. | Diagram of Michelson's experiment | [61] |
| Illustrations of Ether Machine (Lodge). |
| 11. | Diagram of course of light | [69] |
| 12. | General view of whirling part of Ether Machine | [72] |
| 13. | General view of optical frame | [73] |
| 14. | Drawing of optical details | [74] |
| 15. | View of Ether Machine in action | [Frontispiece] |
| 16. | Appearance of interference bands and micrometer wires | [76] |
| 17. | Iron mass for magnetisation | [77] |
| 18. | Appearance of bands | [76] |
| 19. | Arrangement for electrification | [78] |