Today in History-March 3, 1831–Thomas Jennings became the first African-American to receive a patent for his invention of ‘dry-scouring’, a process better known today as dry-cleaning.

As a free man, he established a local business in New York in which he sold clothing. However, customers became disgruntled that there was no means to effectively clean the materials used in the clothing Jennings sold. He took it upon himself to find a solution to this problem. He began testing cleaning liquids in hopes of finding a better way to clean the clothing, the one that worked best was the ‘dry-scouring’ idea which he sought and received patent for in 1831. “Under the United States patent laws of 1793 (and later, as revised in 1836), a person must sign an oath or declaration stating that they were a citizen of the United States” in order to receive a patent. Before the laws revision in 1836, slaves were allowed to make patents also. Since Jennings was free, he was able to patent his idea. It is documented that the money he received from the patent was used to free his family and endorse the abolishment of slavery. However, when the law which allowed him to make his patent was revised in 1836 (5 years after receiving his patent), slaves could not make patents because they were not considered citizens. This law was revised, after slave-owner Oscar Stuart took credit for his slave (Ned’s) invention of the ‘double cotton scraper’. He claimed, “the master is the owner of the fruits of the labor of the slave both manual and intellectual”. This case is essential in understanding the importance of Jennings status as a free man. His freedom validated his citizenship at the time of his patent making him the first African American to receive a patent. Jennings went on to serve as “the assistant secretary for the First Annual Convention of the People of Color in Philadelphia, Pennsylvania”. His accomplishments are extraordinary, making him a monumental figure ‘Today in History’.

For more information, browse the Engineering Pathway’s resources on African American scientists, engineers & inventors and our engineering diversity website.

Readers interested in inventions by African Americans may want to view the following blogs: Ice cream scoop invented (February 2),  First patent by African American Inventor Latimer (February 10), First African American woman to receive an American medical degree (March 1),  First African American to recieve a patent (March 3),  First African-American in Space, (August 30), Howard University founded in 1866 (November 20), John Hopkins hospital performs first open heart surgery (November 29), and Birth of first self-made millionairess (December 23).