As a young girl, Margaret "Mattie" Knight never played with dolls, preferring to make toys for
her brothers instead. In 1849, Knight went to work in a cotton factory where she witnessed a
"shuttle," a device that carries thread back and forth across a textile loom(纺布机), fly off the
machine when the thread broke, striking and killing a young boy about her own age.
     The 12-year-old Knight developed a safety mechanism that made it impossible for a shuttle to
leave the loom. The design was so effective, soon virtually every new power loom carried her
invention, saving countless workers from injury or death. Being so young, she didn't bother to
patent the device, so she never received payment.
     Knight wouldn't make the same mistake later in life when she invented a machine that could
produce flat-bottomed paper bags. Knight had built a small wooden model in her home, but she
needed a metal version to show it could hold up to the stress of mass production. So she hired
Charles Annan to make the full-sized machine for her, only to have him try to claim the patent for
himself. When Knight sued(起诉), Annan's argument was that the design had to be his, because
no woman could possibly understand the complex mechanics. Knight proved him wrong when
she brought back her wooden prototype and explained how every part worked. She won the
case in 1871, making her the second woman to hold an American patent. Over a hundred years
later, her design is still used as the basis for many modern flat-bottom bag machines.
     But that wasn't the last the world heard of Mattie Knight. During her lifetime, she made about
90 inventions and received 26 patents, becoming one of the most productive female inventors of
the 19th century.