General Science, Mathematics, and TechnologyIntroduction |
When was the first patent issued in the United States? |
The first U.S. patent was granted on July 31, 1790 to Samuel Hopkins (1743–1818) of Philadelphia for making “pot ash and pearl ash”—a cleaning formula called potash. It was a key ingredient for making glass, dyeing fabrics, baking, making saltpeter for gun powder, and most importantly for making soap.