Clark Refracting Telescope

Alvan Clark & Sons were the leading telescope opticians in the United States in the second half of the 19th century. The firm came to prominence in 1865 when their 18½-inch refractor, then the largest in the world, was installed in the Dearborn Observatory in Chicago. Other notable achievements included the 26-inch telescope installed in the U.S. Naval Observatory in Washington, D.C., in 1873; the 30-inch objective lens installed in the Imperial Russian Observatory at Pulkowa in 1883; the 36-inch objective lens installed in the Lick Observatory in California in 1887; and the 40-inch objective lens installed in the Yerkes Observatory in Williams Bay, Wisconsin, in 1897.
The Clarks also made many smaller instruments for investigation, education, and recreation. This example is marked "Alvan Clark & Sons 1894 Cambridgeport, Mass." It has a nickel-plated brass tube assembly, an objective lens of 5 inches aperture, an equatorial mount, and a wooden tripod.
Ref: Deborah Jean Warner and Robert B. Ariail, Alvan Clark & Sons. Artists in Optics (Washington, D.C., 1996).
Currently not on view
Object Name
telescope, refractor
date made
Alvan Clark & Sons
overall: 81 1/4 in x 34 1/2 in x 24 in; 206.375 cm x 87.63 cm x 60.96 cm
place made
United States: Massachusetts, Cambridgeport
ID Number
accession number
catalog number
Science & Mathematics
See more items in
Medicine and Science: Physical Sciences
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Clifford Anderson
Additional Media

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