LIST OF ILLUSTRATIONS

FIG.   PAGE
1. Model gyroscope with three degrees of freedom 4
2. Model gyroscope with three degrees of freedom 7
3. Model gyroscope, frictional transmission of turning moment 9
4. Model gyroscope, one degree of freedom lost 11
5. Model gyroscope, second degree of freedom lost 12
6. Model gyroscope, lost degrees of freedom restored 13
7. Elementary gyroscope at equator 15
8. Gyroscopic clock 16
9. Elementary gyro-compass 18
10. Elementary compass at equator 20
11. Elementary compass at 55 deg. N. Lat. 24
12. Compass at equator and near North Pole 26
13. Pendulum and compass 32
14. Damped and undamped vibrations 35
15. Damped pendulum 37
16. Air-blast damping system of Anschütz (1910) compass 43
17. Free and damped motion of axle 49
18. Damping curve from Anschütz (1910) compass 50
19. Damping system of Sperry compass 53
20. Action of excentric pin in Sperry compass 55
21. Action of excentric pin in Sperry compass 57
22. Gyro-pendulum with axle tilted 60
23. Damping system of Brown compass 62
24. The north steaming error at 0 deg. and 60 deg. N. 72
25. Sperry correction mechanism for latitude and north steaming errors 76
26. Ballistic force on compass when ship’s speed changes 83
27. Ballistic force on compass when ship’s speed changes 84
28. Ballistic deflection 86
29. Effect of rolling on due north course 93
30. Effect of rolling on due west course 94
31. External gimbal mounting 97
32. Effect of rolling on a due north course (simple mounting) 98
33. Effect of rolling on a due north course (external gimbal mounting) 99
34. Ship rolling on N.W. course 101
35. Sperry compass on N.W. course 108
36. Sperry ballistic gyro 111
37. Stabilised excentric pin (Sperry compass) 112
38. Diagram of Brown compass 113
39. Oil control bottles (Brown compass) 115
40. Brown compass on west course 117
41. Diagram of Anschütz (1912) compass 121
42. Plans of gyros (Anschütz compass) 122
43. Centrifugal forces on a pendulum 131
44. The Anschütz (1910) compass 139
45. The Sperry compass removed from binnacle 143
46. The Sperry compass 144
47. The Brown compass removed from binnacle 148
48. The Brown compass removed from binnacle 149
49. The Brown compass 150
50. Plan of Anschütz (1912) compass 155
51. Sectional elevation of Anschütz (1912) compass 159