Benjamin Bradley was born into slavery around 1830 by an unidentified slave owner in Annapolis, Maryland. Bradley worked for a printing company at young age while living in Annapolis. At 16 he learned a skill in mechanical engineering. Bradley constructed a model of a steam engine out of two pieces of steel, a gun barrel, and pewter. His owner was impressed by this accomplishment arranged for Bradley to work at the Department of Natural and Experimental Philosophy at the Naval Academy in Annapolis, Maryland. Bradley would became the first African American to hold any but menial posts at the Naval Academy.
Bradley would learn how to read and write at the Academy. During this time he became an assistant who set up experiments for the Academy’s faculty.
While working at the Naval Academy Bradley sold his first small steam engine to a Midshipman living in Annapolis. This engine was powerful enough to run a small boat. Bradley used this money to expand on his findings and create an even larger model.
The around 1856 Bradley built an engine that was capable of propelling the first sloop-of-war (a small warship carrying guns on one deck) at the rate of 16 knots an hour. Bradley engine was the first ever created that was powerful enough to run a war ship. Bradley was unable to patent his invention under the United States law at the time because he was a slave. Bradley would sold the engine and earn enough money to purchase his freedom. The date of his death is unknown.
Rupert, A. (2009, February 21). Benjamin Bradley (1830-?). BlackPast.org. https://www.blackpast.org/african-american-history/bradley-benjamin-1830/
Michael Brodie, Created Equal: The Lives and Ideas of Black American Innovators (New York: William Morrow and Company, Inc., 1993); Jim Haskins, Outward Dreams: Black Inventors and Their Inventions (New York: Walker Publishing Company, Inc., 1991).
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