Born in 1731, Benjamin Banneker was one of the first African Americans recognized as an accomplished astrologist and mathematician. From 1791 to 1802, he published the "Pennsylvania, Delaware, Maryland and Virginia Almanac and Ephemeris," an annual journal that included tidal information, medical treatments and eclipse predictions.
Banneker escaped the bondage of slavery as the child of free black parents in Maryland. By studying stars, he taught himself astrology and borrowed text books to learn mathematics.
In 1752, after examining the mechanics of a borrowed pocket watch, he created the first wooden clock ever built in America. It worked precisely for more than 40 years, before a fire destroyed it.
Banneker caught the attention of Thomas Jefferson in 1789, after correctly predicting a solar eclipse. As a result, he was assigned to take part in the survey team that mapped out the nation's new capital of Washington DC.
His association with Jefferson continued through out his professional life. In 1791, Banneker wrote a letter to Jefferson that criticized his ownership of slaves. Jefferson responded, and Banneker published the communications in his 1793 almanac.
In his later years, Banneker continued to speak out against slavery as an active abolitionist. He died in 1806 near his family home in Ellicott City, Maryland.