Lenses and Mirrors to See the Universe
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Lenses and Mirrors to See the Universe Astronomy has changed a great deal since 1608, when the Dutch optician Hans Lippershey was refused a patent for his invention of the telescope. His patent was refused on the grounds that scientists had been using magnifying lenses since the 13th Century to study nature. Galileo heard of Lippershey's invention, though, and built one of his own. His observations eventuaUy caused a great stir among the scientific Community, not to mention extreme distress to the Catholic church. Lippershey's type of telescope, with magnifying lenses mounted on the ends of a tube, is a refracting telescope. A Century ago this year, one of the largest refractors in the world (36 inches in diameter) was installed on Mount Hamilton, near San Jose, California. The project to establish an observatory on Mount Hamilton—then a complete wilderness—was funded by the eccentric millionaire James Lick, who had made his fortune in the California gold rush. The Alvan G. Clark Company of Cambridge, Massachusetts, then the master telescope maker in the United States, created the 36-inch objective lens after several years of work. Thomas Fräser, one of the two men Lick designated to supervise the observatory's construction, rraveled in winter from California to Massachusetts so he could accompany the completed lenses on their joumey back to San Jose. Alvan Clark was careful to pack the precious lenses in a wooden box padded with human hair, which was then sealed inside a steel box to protect it on the long train ride. (The railroads gave the private car special priori ty.) Once back in San Jose, Fräser transferred the box containing the lenses to a wagon, which he then took up the winding and treacherous road to the top of the mountain. Fräser and Richard Hoyd, the second Supervisor of the observatory's construction, installed the lens into the cell that would be mounted to the telescope. Though the 36-inch refractor was ready for Operation on December 31, 1887, the worst winter storm in decades Struck Mount Hamilton. Four days later the sky finally cleared, but the dorne was frozen into position and could not be rotated. Nevertheless, observers managed to focus on a star overhead, Aldebaran. Several days later, when the observers first looked 82
at Saturn as it crossed the narrow window of visibility through the frozen dorne, one of the assistants wrote that it was "the greatest telescope spectacle ever beheld by man." The largest refracting telescope in existence today is the 40-inch refractor at Yerkes Observatory in Williams Bay, Wisconsin. It was installed in 1897 under the supervision of George Ellery Haie, a physics graduate of the Massachusetts Institute of Technology. Haie was running a small observatory in Chicago when he learned, at a scientific meeting in the surruner of 1892, that a pair of 40-inch glass disks were available. They had been made by the Paris firm, Mantois, and had tested out to be optically perfect by the Alvan G. Clark Company. George Haie, ambitious and only 24, took his idea to Wil
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