Inventor and mathematician who created a computerized switching system for Bell Labs, the principles of which were used for generations.
She earned a Ph.D. from Yale University, majoring in philosophy and mathematical foundations.
She was rewarded by Bell Labs with a supervisor post for devising a way in which they could handle more phone calls.
She was in the hospital giving birth to one of her three sons when she devised the idea for the new switching system.
She and Sarah Grimke both made professional contributions that helped women gain equality with men.