26-inch Refracting Telescope

$26-inch Refractor Telescope Column, 25 feet high, weight 18 tons. Polar axis of steel, 9 inches in diameter weight 1800 pounds. Declination axis of steel, 8 inches in diameter, weight 1200 pounds Main driving wheel, 51 inches in diameter Rotating the polar axis moves 6 1/2 tons Rotating the declination axis moves 2 tons. Objective lens made by Alvan Clark and Sons, circa 1873, 26 inches clear aperture, weight with cell 220 pounds, focal length 32.475 feet, faintest star observable 16.3 magnitude (Argelander scale extended), separating power .18 seconds of arc (Dawes Formula), scale 1mm. equals 20.84 seconds of arc. Tube 32 1/2 feet long, 32 inches in diameter, weight 1 1/2 tons. Total weight of telescope and mounting, 28 tons.$ ref11d.jpg

$26-inch Refractor Telescope Column, 25 feet high, weight 18 tons. Polar axis of steel, 9 inches in diameter weight 1800 pounds. Declination axis of steel, 8 inches in diameter, weight 1200 pounds Main driving wheel, 51 inches in diameter Rotating the polar axis moves 6 1/2 tons Rotating the declination axis moves 2 tons. Objective lens made by Alvan Clark and Sons, circa 1873, 26 inches clear aperture, weight with cell 220 pounds, focal length 32.475 feet, faintest star observable 16.3 magnitude (Argelander scale extended), separating power .18 seconds of arc (Dawes Formula), scale 1mm. equals 20.84 seconds of arc. Tube 32 1/2 feet long, 32 inches in diameter, weight 1 1/2 tons. Total weight of telescope and mounting, 28 tons. Photo taken in March 1961.$ ref11e.jpg