DICTIONARY OF

Gyro Compass 160 Gyrostat
Gyro Compass. Gyroscope so mounted, ballasted and fitted that the diurnal revolution of
Earth is made to constrain the North-South line of compass to seek the meridian, and remain
in it. Speed of gyro varies with different makes: Anshutz being 20,000, Brown 14,000,
Sperry 6000, Arma-Brown 11,800, revolutions per minute. Weights of rotors are
respectively, 5 Ib., 4 ½ Ib., 52 Ib. and ½ Ib. Corrections have to be made for latitude and
speed of ship; some corrections are made by hand, others are automatically adjusted by the
compass. Gyro compasses are ineffective in latitudes higher than about 75°.
Gyropilot. Gyro-controlled automatic steering device.
Gyro Repeater. Electrically-operated dial that is graduated as a compass and kept in step
with master gyro compass; so indicating position of gyro compass at stations remote from it.
Gyroscope. Rapidly-rotating wheel so mounted that it has three degrees of freedom:
1, freedom to rotate on its own axis; 2, freedom from constraint about its horizontal axis;
3, freedom from restraint about its vertical axis. These allow the rotating body to keep its
direction in space unless otherwise disturbed.
Gyrostat. Rapidly rotating wheel that is constrained about either its vertical or its horizontal
axis. It thus has two degrees, only, of freedom.