Margaret E. Knight was an ingenious woman. She started tinkering with things when she was still just a tiny child, and the first invention that really improved the lives of those around her came about at the age of 12.
Research:

SYMHC Classics: Dr. Lucy Hobbs Taylor
29:58

Behind the Scenes Minis: Carry-on Bags
28:38

Gustave Flaubert and the ‘Madame Bovary’ Trial
45:15