Benjamin Banneker (November 9, 1731 - October 19, 1806) was a mathematician, astronomer, almanac author, surveyor, naturalist and farmer. Born in Baltimore County, Maryland, to a free African-American woman and a former slave, Banneker had little formal education and was largely self-taught. The education that he did receive was thought to come from neighbouring Quakers who had established a school near the Banneker farm which provided him with his only classroom instruction.

Banneker is most famous for his widely published almanacs (1792-1797) for which he calculated the daily locations of stars and planets, forecast lunar and solar eclipses and included opinion pieces, literature, medical and tidal information. Their accuracy was validated by authorities in the field who endorsed Banneker’s work without exception. Banneker was an outspoken anti-slavery supporter who corresponded with Thomas Jefferson on slavery and racial equality and included the correspondence between them in his 1793 almanac.

Banneker did construct a wooden clock despite reputedly having seen only one other timepiece in his life. His clock output, however, was only the one and didn’t extend to exports. Similarly, there is little doubt that Banneker spent time assisting Major Andrew Ellicott in surveying the borders and layout of the original federal capital of the District of Columbia. However, his involvement in that project was brief and much exaggerated by his later enthusiastic admirers.

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