E.S. Williamson’s “spring lift for stoopers,” patented in 1922, was essentially a stiff spring that a laborer could mount on his back “so that when the wearer bends over or stoops this spring body member is flexed and exerts a tendency to support and balance the bent-over portion of the body, whereby the muscles ordinarily brought into play to balance and support the body in such position need not be fully exercised and can rest.”

The wearer can sit or kneel normally, and there’s even an attachment to help bear the weight of a shovel during heavy work. “Thus it will be seen that a workman equipped with my device will not tire as easily and can do more work more comfortably and easily.”