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| | World Almanac for Kids |
 | | TELESCOPE, a lens, mirror, or other reflecting surface used to form an image of a distant object, together with a microscope, for the observer, a photographic camera, or some form of spectroscopic apparatus. |
 | | The mirrors for reflecting telescopes were usually made of speculum metal, a mixture of copper and tin, until the German chemist Baron Justus von Liebig discovered the method of depositing a film of silver on a glass surface. |
 | | In England, telescopes were mounted by having the polar axis supported at each end, but the German system, in which the mounting is in the center and the weight of the telescope is balanced by counterpoises, is not generally used for large refractors, and a modified form is employed for reflectors. |
| www.worldalmanacforkids.com /explore/space/telescope.html (1180 words) |
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