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Wednesday, March 28, 2007

What is a compass?

Well, have you ever thought what a compass is? I can tell you a little I know about it. Compass is an instrument that contains a freely suspended magnetic element. And this element, on the other hand, displays the direction of the horizontal component of the Earth's magnetic field at the point of observation.
This magnetic device is known as an old Chinese invention. Compass' ancestor is called lodestone, and it was used to construct fortune telling boards. But later on someone noticed that lodestones point out real directions, that was the beginning of a first compass. The pointing need in that early time compass was a lodestone spoon-shaped device, with a handle that always pointed south.
Posted by OpticsPlanet at 2:14 PM Read Article

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