Benjamin Banneker, originally Banna Ka, or Bannakay (November 9, 1731 – October 9, 1806)) was an African-American astronomer, clockmaker, and publisher, and was instrumental in surveying the District of Columbia.

Benjamin Banneker's mother was Mary Banneky, whose mother, Molly Welsh, was accused of stealing milk and sent from England to America as punishment. She became the owner of a farm and married one of her slaves, whom she freed.

Benjamin's father, Robert Bannakay, built a series of dams and watercourses that successfully irrigated the family farm, where Banneker lived most of his life. Banneker was taught to read and do simple arithmetic by his grandmother and by a Quaker schoolmaster, who changed his name to Banneker. Once he was old enough to help on his parents' farm, his formal education ended.

At 21, Banneker saw a neighbor's patent pocket watch, borrowed it, took it apart to draw all its pieces, then reassembled it, and returned it running to its owner. Banneker then carved large-scale wooden replicas of each piece, calculating the gear assemblies himself, and used the parts to make a striking clock. The clock continued to work, striking each hour, for more than 40 years.

This event changed his life, and he became a watch and clock builder. One customer was Joseph Ellicott, a surveyor, who needed a very accurate timepiece to make correct calculations of the locations of stars. Ellicott was impressed with his work and lent him books on mathematics and astronomy.

Banneker began his study of astronomy at age 58. He was able to make the calculations to predict solar and lunar eclipses and to compile an ephemeris for the Benjamin Banneker's Almanac, which he published from 1792 through 1797. He became known as the Sable Astronomer.

In 1791, he was hired to assist brothers Andrew and Joseph Ellicott to work with French architect Pierre L'Enfant by surveying the Federal District to lay out the new capital of the United States.

Also in 1791, Banneker wrote to Secretary of State, and author of the Declaration of Independence Thomas Jefferson, with an eloquent plea for justice for African Americans, calling on the colonists' personal experience as "slaves" of Britain and quoting Jefferson's own words. As a subtle hint of the capabilities of his people, Banneker included a copy of his newly published almanac with its astronomical calculations. Jefferson acknowledged Banneker's intellectual achievements, but did not help to abolish slavery.

Bibliography

" The Life of Benjamin Banneker: The first African-American Man of Science" by Silvio A. Bedini ISBN 0-938420-63-1.

External links

• Benjamin Banneker Historical Park & Museum
• The Friends of Benjamin Banneker Historical Park & Museum