Abstract Records of Dearborn Observatory, built in 1865 by the Chicago Astronomical Society and the University of Chicago and in 1889 moved to Northwestern University's Evanston campus. Dearborn Observatory was a significant contributor in the area of double star research. The records consist almost entirely of observational data gathered by astronomers using Dearborn's 18-1/2 inch refracting telescope or its meridian circle, calculations performed on the data, and the results of such...

Abstract Astronomer Truman Safford was the first director of the Dearborn Observatory (in its old location on the South Side of Chicago, before it was moved in 1889 to Northwestern University). The records consist mainly of notebooks in which he recorded observations, calculations and notes. Materials include Safford's teaching files from the first University of Chicago, astronomical observations, computations regarding celestial objects, extracts from astronomical catalogs and two manuscripts. One...