The geography of the heavens, and class-book of astronomy: accompanied by a celestial atlas (1873)
Burritt, Elijah H. (Elijah Hinsdale), 1794-1838, Mattison, Hiram, 1811-1868, ed, Whitall, Henry, 1819-1887? Celestial planisphere · New York, Sheldon & company · leaf 327
. This instrument is located in the Observatory of the HighSchool of Philadelphia, Its focal length is eight feet, and itsaperture six inches—the same as the one on the preceding page.It was made by Merz <fc Mahler, of Munich, and cost $2,200. * We are indebted to the courtesy of Messrs. Harper… … 698. This instrument has a focal length of sixteen feet, withan object-glass thirteen-and-a-half inches in diameter. Its focallength is therefore about four feet less than is usual in the Mu-nich instruments of the same aperture. The flint and crownglass discs for it were imported from Germany, and…
Constellations · Stars
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