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Margaret Knight

Invention of the Paper Bag Machine

For many women inventors in years past, the invention process was twice as difficult because, in addition to the hardships of inventing, they also faced the skepticism of a world that didn't believe women could create something of value. Fortunately, over the years, that perception has been blown out of the water by women inventors like Margaret E. Knight, who were willing to fight for the accolades and recognition they unquestionably deserved.

Born in Maine in 1838 and raised by a widowed mother, Margaret Knight showed a proclivity toward inventing from a very young age – a characteristic of many of the world's famous inventors. After observing an accident at a textile mill at the age of 12, Margaret went to work producing her first real invention. Knight conceived a device that would automatically stop a machine if something got caught in it. By the time she was a teenager the invention was being used in the mills.

After the Civil war, Margaret Knight went to work in a Massachusetts paper bag plant. While working in the plant, Knight thought how much easier it would be to pack items in paper bags if the bottoms were flat (they were not at the time). That idea inspired Margaret to create the machine that would transform her into a famous woman inventor. Knight's machine automatically folded and glued paper-bag bottoms – creating the flat-bottom paper bags that are still used to this very day in most grocery stores.

Of course, no story of triumph would be complete without a villain. In this case, the villain was a man named Charles Annan – who attempted to steal Knight's idea (he spied on the woman hired to make her prototype) and receive credit for the patent. Not one to give in without a fight, Margaret took Annan to court to vie for the patent that rightfully belonged to her. While Annan argued simply that a woman could never design such an innovative machine, Knight displayed actual evidence that the invention indeed belonged to her. As a result, Margaret Knight received her patent in 1871.

Knight's invention immediately had a huge impact on the paper industry – and paper bags began to proliferate throughout the retail landscape. To this very day, thousands of machines based on Margaret Knight's idea are still used to produce flat-bottom paper bags. Knight didn't stop there though; throughout her lifetime she would receive over 20 patents and conceive almost 100 different inventions – including a rotary engine, shoe-cutting machine and a dress and skirt shield. At the time of her death, an obituary described Knight as a "woman Edison." In actuality, she was something greater – she was a woman inventor named Margaret Knight.