Dearborn Telescope

Dearborn Telescope Soundex Code D616

Wikipedia page about the Dearborn Telescope

In 1863 the firm of Alvan Clark & Sons constructed an 18.5" lens for a telescope, which made it, at the time, the largest refracting telescope in the world. The lens had been commissioned by the University of Mississippi. However, the American Civil War began before the lens could be delivered. The lens therefore remained in the Clark's shop in Cambridge, Massachusetts where it was eventually put up for sale.

The lens was bought instead by the Chicago Astronomical Society, for the sum of $11,187. The Chicago Astronomical Society intended the lens for the University of Chicago and a tower was constructed on Cottage Grove Avenue around the lens. The structure was named the "Dearborn Observatory."

In 1887, the Chicago Astronomical Society signed a deal with Northwestern University to bring the telescope to Evanston, and a new observatory was built on Northwestern's Evanston Campus to house the telescope.