African Americans’ scientific ingenuity has created numerous devices that have improved the quality of life and increased productivity and boosted business profits. A notable early invention was astronomer Benjamin Banneker’s watch created in 1753. Nineteenth century inventors were free-born, enslaved, and formerly enslaved people whose fields included dentistry, education, farming, and manufacturing. The U.S. Patent Law was enacted in 1790. Thomas Jennings was the first African American inventor to receive at patent in 1821. He used the proceeds from his dry cleaning process patent to liberate his enslaved family and contribute to the abolitionist movement. Lewis Temple of New Bedford invented the toggle harpoon that revolutionized the whaling industry, and Jan Matzeliger's shoe lasting machine greatly advanced shoe manufacturing.