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Mordecai Yarnall

Mordecai Yarnall (1816-1879) is best known for his work on star catalogues. He was appointed a Professor of Mathematics in 1839, worked with O. M. Mitchel at the Cincinnati Observatory during the 1840s, and came to the Naval Observatory in 1852. At the Naval Observatory Yarnall became the quintessential observer with the meridian instruments, including the 5.3-inch transit instrument and the mural circle. Yarnall's star catalogs of 1873 and 1878 gained wide respect for the Observatory. Gift of Yarnall Family
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