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Margaret E. Knight

Margaret E. Knight


American Inventor

As a woman and an inventor, Margaret Knight is significant due to the number of inventions she produced and for the number of patents she received during her lifetime. Her most notable work was her development of the first machine capable of making square-bottomed paper bags.

Margaret Knight was born in York, Maine, on February 14, 1838. Mattie, as her parents and friends called her, had woodworking tools as favorite toys, which she enjoyed putting to use to make things. She later said of her childhood, "the only things I wanted were a jack knife, a gimlet (a tool for boring holes) and pieces of wood." She received some education through secondary school but no formal education beyond this. As a child and an adult, Knight used her creative mind and her interest in mechanical things to produce many inventions.

Knight's family moved to New Hampshire during her childhood. Like many other young people during the early years of the industrial era in the United States, her brothers became employees of a local cotton textile mill. It is believed that Knight conceived the idea of her first invention in this mill.

At age 12, Knight visited her brothers at work. She watched the heavy steel-tipped shuttles move on the large looms. While watching, she saw a loom malfunction and a shuttle fly out and hit a worker. She designed a safety device to prevent this type of accident. Her shuttle restraining device turned the entire machine off when something malfunctioned. When used, it kept shuttles from falling out of the looms.

As an adult, Knight went to work in a paper bag shop in Springfield, Massachusetts. The bags being made were weak, narrow bags with an envelope shape. Like others, Knight worked to develop a better design. Knight's efforts to improve the bag design led to her improving the machine used to make paper bags. The new part she developed enabled the machines to fold square-bottomed bags. Unlike their flat predecessors, these new bags were superior in strength, and their ability to stand made them more practical. Knight took out her first patent for this invention in 1870.

Knight is best known for her inventions in the paper bag industry. She acquired two more patents in 1871 and 1879 for further improvements she made to the paper bag machine. Grocery stores around the world still use her bag design.

Knight invented three domestic items in the 1880s. In 1883 she designed a dress and skirt shield. The next year she developed a clasp for holding robes. Then in 1885 she designed a spit; a spit is a long, pointed tool used to skewer meat for cooking.

In 1890 Knight turned to a new field for her inventions. This time she focused on the making of shoes. Before shoes were sewn together, a person or machine used a pattern to cut them out of large pieces of material. Knight designed several machines that improved this process of shoe cutting. In just four years she acquired six patents for her inventions in this field.

A few years passed before Knight began working with motors and rotary engines to produce her next set of inventions. In the early 1900s she created a number of components for rotary engines and motors. Her first was patented in 1902, her last in 1915. The sleeve-valve automobile engine was her most notable invention in this category. Knight's lack of education prevented her from fully understanding the mechanics behind engines and motors and limited her understanding of her own work.

When she died in 1914, Knight had acquired at least 27 patents and made approximately 90 inventions. Her largely self-taught abilities and great interest in machinery made her an extraordinary American inventor of the industrial era.


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