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- A compass is any instrument for finding
- direction. A magnetic compass is most
- commonly used, consisting of a thin piece of
- magnetic material with the north-seeking pole
- indicated, free to rotate on a pivot and
- mounted on a compass card on which the points
- of the compass are marked. When the compass
- is properly adjusted and used, the
- north-seeking pole will point to the magnetic
- north, from which true north can be found
- from tables of magnetic corrections.
- Compasses not dependent on the magnet are
- gyrocompasses, dependent on the gyroscope,
- and radiocompasses, dependent on the use of
- radio. These are unaffected by the presence
- of iron and by magnetic anomalies of the
- Earth's magnetic field, and are widely used
- in ships and aircraft. See navigation.
-
- Subject by: Samantha Good
-