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Show Ky Piece for the Lick Teleieop. The Gunlach optical works of this city have just completed an eye piece for the great Lick telescope. The eye piece is constructed on a perfected theory and is a great deal larger than any before made. Eye pieces of the same pattern are in use in many of the observatories in the country and everywhere excellent results are obtained.'' The GunlacH glass uses all the light gathered by the large field lens and at the same time covers the area of the larger glass of the telescope. There are two lenses in this eye piece. They are six inches apart. The larger one is called the .field Jens and, is six and one-half inches in diameter, . . , , . The other lens is the eyeglass proper. It is, three inches in diameter and is composed com-posed of three lenses, a double concave, double convex and meniscus cemented togetHr. The field lens u of crown glass. The concave and, convex lenses are also of crown glass. The meniscus, or correcting cor-recting lens, is of -flint glass. No other eye piece of anything like equal dimensions dimen-sions has ever been made. The largest now in use is not over two inches in diameter, di-ameter, and that is far above the average size. The light from heavenly bodies seen through the Lick telescope and this eye piece will be 20,000 times as bright as that seen with the naked eye. Roches-tor Roches-tor Democrat. |