large ships. The action of these devices is based on the fact, proven in Art. 25, that if a body oscillating with a periodic angular motion be acted upon by a torque of the same period, and in the opposite phase to the velocity of the oscillating body, then the system producing the periodic torque will absorb energy from the oscillating body.
§2. The Inactive Type of Gyro Ship Stabilizer
88. The Effect on the Motion of a Swinging Pendulum Produced by an Attached Gyroscope: (a) When the Precession of the Gyro-Axle is Opposed by a Frictional Torque. Experiment. - The pendulum shown in Fig. 106 carries a gyro-wheel mounted so as to have two degrees of rotational freedom. The gyro-wheel spins about a nearly vertical axis through the center of mass of the wheel and attached frame, and it is capable of rotation about a perpendicular axis AA' in the plane of