Which of the following kitchen appliances was used to help create the first polio vaccine?

My brother Dan had polio when he was young. It didn't cripple him. He was always kinda puny and also fell out of the oak tree in our backyard a quite a few times. The Army drafted him for Vietnam. He "filled out" and became a Medic.

Thank you Salk and Sabin !

I believe there are still a couple of patients in Iron lungs from that time following paralysis by polio