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Astronomy In California 1850 – 1950:
Telescope Makers, Telescopes, and Artifacts
Reflecting Telescope
By the John A. Brashear Company, American Telescope Maker
The John A. Brashear Company of Pittsburgh, Pennsylvania, under the guidance of John Brashear, J.B. McDowell, and Charles Hastings, made Chabot Observatory's 20-inch refractor, the company’s best representative in California. But the John A. Brashear Company also made reflector telescopes for professional observatories. In fact, John Brashear's very first successful telescope objective was a 12-inch reflector telescope mirror that he made at the age of 32 when he was still a rolling-mill foreman in Pittsburgh.
Fortunately, through the generosity of philanthropist William Thaw, Brashear left the rolling mill in 1881 to set himself up as a telescope and instrument maker. An 18-inch for Philadelphia, the Chabot 20-inch in Oakland, and a 24-inch for Swarthmore were among the important refractor telescopes produced by the John A. Brashear Company up until Brashear's death in 1920. But all of the largest (and more impressive) Brashear telescopes are reflectors. Large Brashear reflectors are in Chile (a 36-inch reflector made for Lick Observatory's station in Santiago in 1904), Pittsburgh (Allegheny Observatory's 30-inch reflector), and Victoria, Canada (the gigantic 72-inch reflector completed in 1918).
This exhibit contains a small Brashear reflector telescope. The tube is 77 1/2 inches long overall and 10 inches in diameter. The main mirror is silvered glass about 9 1/2 inches in diameter. On the bottom of the mirror is a signature in pencil: "by John A. Brashear, about 1900-1910." The telescope mount, which is equatorial, is cast iron painted dark gray.
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