7. Margaret Eloise Knight
People deemed Margaret Eloise Knight one of the best American inventors. She’s the original inventor of the flat-bottomed paper bag and later went on to patent a dress and skirt shield, a clasp for robes, and a cooking spit. In fact, Knight had many as about 30 patents to her name. She was definitely a looker, too, with that charming smile and beautifully-curled hair. And behind those sparkling eyes were likely ideas for more inventions that this beauty never got to bring to fruition. Unfortunately, she had no interest in a spouse and never married or had children.