Skip to content

RICS 150

27 MAR 2018

Benjamin Banneker: Surveying with the stars

Benjamin Banneker is best known for being part of a group led by Major Ellicott in 1791 to survey the border of the new federal District of Columbia, which would become the capital of the United States.

In 1791 surveyor Major Ellicott personally hired Benjamin to assist in the initial survey of the boundaries of the new federal state. The state which was formed from land between the Potomac River, Maryland and Virginia State, had ceded to the federal government the year prior to the survey.

Ellicott’s team placed boundary stones at, or near every mile of the 100-square mile territory. According to biographers Banneker’s main duties involved making astronomical observations.

Benjamin, who was also a keen horologist,would calculate his location by relating points on the ground to the positions of stars at specific times. This was particularly important at Jones Point in Alexandria, where Benjamin was able to ascertain the surveys starting point.  

Benjamin put his star gazing abilities to other uses, publishing his first almanac “Pennsylvania, Delaware, Maryland and Virginia Almanac and Ephemeris” in 1792. His book contained not only astronomical events such as sunrise and sunsets, but it also contained times for meetings of the courts including the Supreme Court. In his lifetime, Benjamin published six almanacs in 28 editions.

Benjamin was also well-known for having corresponded with Thomas Jefferson on the topics of slavery and racial equality. In his first letter to Jefferson in 1776, Benjamin quoted language from the Declaration of Independence, expressing a plea for justice for African Americans.

As one of America’s first African American surveyors, Benjamin’s achievements have been widely celebrated. In 1980 the United States Postal Service commissioned several stamps to feature his portrait and a number of recreational, cultural and educational sites throughout the US have commemorated Benjamin’s works.