Woman of the Week - Margaret Knight

For the next few months, we’ve decided to dig into the CR4 archives and expand upon some blog posts from 2007. Back then, we published a series of lists of women inventors and now we will write full blog posts about those who have yet to be featured. Do you know of a great person to be a subject? Let us know!

This week, we chose Margaret Knight. She is an inventor of numerous machines and mechanisms but is perhaps most well-known for creating the idea of the flat-bottom paper bag.

Source:MIT

She was born in 1838 in York, Maine. Her father died when she as very young and the family moved to Manchester, New Hampshire. She left school early to start working at a cotton mill with her siblings.

Right from the start of her working life, she began coming up with solutions to problems she saw. At 12, she witnessed an accident at work where a worker was stabbed by a steel-tipped shuttle after it shot out of one of the mechanical looms. Within a few weeks, she invented a safety device to prevent more accidents like this. The device would automatically stop the machine if something became stuck.

After the Civil War, she started work at a paper bag plant in Massachusetts. At the time, the bottoms of paper bags were not flat. Knight thought that it would be much easier to pack things in the bag if it did have a flat bottom.

Knight built a wooden model of a device that automatically folded and glued a flat bottom to the bags. But in order to apply for a patent, she needed to build an iron version of the model.

Charles Annan, who was in the machine shop as she was working on the iron model, stole her design and patented the device. Knight filed a successful patent interference lawsuit and was awarded the patent in 1871.

Alongside a business partner, Knight established the Eastern Paper Bag Co. and received royalties. The invention made a huge impact on the retail landscape. To this day, flat bottom paper bags can be found in most grocery stores. They’re also used on a smaller scale to pack brown bag lunches and on a larger scale for collecting lawn clippings.

She created many other inventions and received several more patents over the years. They ranged from a number machine, a window frame and sash and lid-removing pliers.

She died in 1914 at age 76. She was inducted into the National Inventors Hall of Fame in 2006. The original bag-making machine is on display at the Smithsonian in Washington D.C.