Compensating compass deviation in iron ships (Airy)
Compensación del desvío del compás en buques de hierro (Airy)
- Date
- 1839 · confidence high
- Place
- Royal Observatory, Greenwich, London, United Kingdom
- Credited to
- George Biddell Airy
- Field
- Movement
What was discovered
Airy showed on the Rainbow (1838) that a ship's iron hull deflects the needle and that the deviation can be cancelled with magnets and soft-iron masses placed near the compass. It solved the problem that prevented safe navigation in iron ships.
The problem had earlier been tackled by Matthew Flinders (1801-1804, the Flinders bar); Airy applied a systematic solution.
What it led to
- compensated compasses for the navy
- the theory of Archibald Smith and Kelvin
- deviation cards for iron and steel ships