What piece of equipment inspired Massachusetts Shaker Tabitha Babbitt to invent the circular saw in 1813?
The spinning wheel. Babbitt was working in a Shaker spinning house when she realized that the wheel could be applied to cutting logs. At the time, two-man pit saws were used in saw mills, and half the sawing motion was lost. Babbitt made a thin toothed disk, put it on the spindle of her spinning wheel, and discovered that her rotating circular blade could saw wood much more efficiently.