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

A compass is an instrument containing a freely suspended magnetic element which displays the direction of the horizontal component of the Earth’s magnetic field at the point of observation.

Magnetic compass is the most important of all instruments aboard even the most modern vessel and it is probably the most reliable. It’s origins go back as long ago as 2300 BC, but the Chinese development of the compass card dates to the 14^th century and the sophisticated instrument we know today became stabilized with the advent of steel ships in the 19^th century.

Magnetic compass is a primary means of navigation as a direction indicating device, of a ship.