Wheelchair Model Premier C12673, Manufacturer Everest and Jennings Company, Don Mills, Ontario, post 1968. Canada Science and Technology Museum, artifact no. 1983.0029. 

In 1933, California engineers, Herbert Everest (who had paralysis) and Harry Jennings, re-designed the wheelchair to improve the folding chairs then available. They lightened the structure using cloth and metal tubing and put the drive wheels at the rear. Everest could tip the chair over obstacles and work at a desk. As form followed function, the wheelchair acquired a modern look. Why then did old-fashioned heavy chairs remain so common for another decade?