11. Margaret E. Knight
Margaret E. Knight, a prolific American inventor, created her first invention while working in a cotton mill with only an education that ended when she was 12. She witnessed an industrial accident in which a man was stabbed by a shuttle that came out of a cotton loom. She invented an unknown safety device for the loom that was reportedly adopted by other looms throughout the northeastern United States.
After moving to Massachusetts from New Hampshire, Knight began working at a paper bag factory. While working there, in 1868, she invented a press to create the flat-bottom, sealed paper bags that we still use today. A man who worked in the machine shop where Knight’s iron prototype of the press was being built stole her idea and patented the device. She sued him for patent interference and was successful, receiving a patent for the invention in 1871.
At her death, at the age of 76, in 1914 she held 87 U.S. patents. She patented designs for numerous items including motors, reels, cutting machines, and more. She was posthumously inducted into the inventor’s hall of fame in 2006. Her original iron prototype paper bag machine is preserved in the Smithsonian Museum.
