What is a Magnetic Compass, its principle, types and errors?

July 22, 2016

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Dry card compass.
Wet card compass.

Dry card compass:

In olden days there used to be a dry card compass on the upper bridge for use in navigation. It is now part of history.

Made by rice paper.
Diameter 254mm (10 inches)
Cover aluminum ring.
Silk thread used to be attached.
The weight of the card is usually around is grams.

Wet card compass:

Made of mica
Diameter 15cm
Bowl diameter 23cm

The ring magnet wet card compass is the most efficient type of marine magnetic compass.

The bowl is filled with a mixture of distilled water and pure ethyl alcohol so that the mixture has the following properties.

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About the author

Amit Sharma

Graduated from M.E.R.I. Mumbai (Mumbai University), After a brief sailing founded this website with the idea to bring the maritime education online which must be free and available for all at all times and to find basic solutions that are of extreme importance to a seafarer by our innovative ideas.

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3 Comments

Magnetic Compass - When does it need an adjustment? - Ocean-Faring says:

December 20, 2018 at 11:33 pm

[…] Compass Errors & Principles retrofits of the magnetic compass I need to take care of? […]

Reply
Capt k p joy says:

October 6, 2018 at 9:20 pm

Good work..

Reply
Lubna manzoor says:

July 19, 2018 at 12:26 am

Thanks!JAZAKALLAH

Reply

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