Invention of the compass

The compass is a device used to determine direction on the surface of the earth. The most familiar type of compass is the magnetic compass, which relies on the fact that a magnetic object tends to align itself with Earth's magnetic field.It dates back to the first century B.C,the Chinese learned that pieces of lodestone (an iron metal) always pointed North when placed on a flat surface.The discovery of Earth's magnetic field, electric energy carried between the North and South poles has been traced to the use of the lodestone.




Other types of compasses determine direction by using the position of the Sun or a star, or by relying on the fact that a rapidly spinning object (a gyroscope) tends to resist being turned away from the direction in which its axis is pointing.



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The north magnetic pole is situated at the northernmost point of the Arctic coast of north America and all compass needles in the northern Hemisphere point toward this point. But ancient people didn't know the difference. The sailors of later days noticed the difference and were greatly puzzled. After that this kind of puzzle came to the point and the difference between north geographical pole and north magnetic pole was considered and treated differently.