Appendix VII
The Gyroscope
The importance of the gyroscope in connection with the present subject is due to the fact that in certain actual cases, as in the flight of a projectile from a rifled gun, and in the flight of a boomerang, gyroscopic action plays an important part; and further, the gyroscope has actually been proposed as a means of securing stability in the flight of an aeronautical machine.
In view of these facts, and in view of the contingent possibility of the employment of gyroscopic action as a means of improving the stability of a flying machine, it has been thought desirable to include in the present work a discussion of the theory of the gyroscope, and an account of some of the more important of its present applications.
It is usual to treat the gyroscope and problems involving gyroscopic action exclusively by mathematical methods, in which the physical reality of the problem is partially obscured. One result of this is that, in spite of the unimpeachable nature of the said methods, mistakes are not infrequently made, even the direction of the gyroscopic torque is sometimes misstated.[1]
The author has for many years employed a direct method of
- ↑ In his "Dynamo Electric Machinery" (4th ed.), p. 388. Silvanus P. Thompson, discussing the gyroscopic couple, says:—"... Then F = 30.6lbs, on each bearing alternately acting up and down at each roll, if the axis of the dynamo lies athwart the ship." The actual direction of the gyroscopic couple is about an axis at right angles to the forced precession; in the case in point the resulting stresses on the hearings are horizontal, not vertical as stated.
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