Mary Beatrice Davidson Kenner

"Mom, don’t you think someone could invent a self-oiling door hinge?” At just six years old, Mary dedicated herself to the invention. “I [hurt] my hands trying to make something that, in my mind, would be good for the door. After that I dropped it, but never forgot it.”

Mary Beatrice Davidson Kenner, N.D.,

The Sanitary Belt, N.D.,