26 maio 1813 ano - circular saw

Descrição:

A weaver named Tabitha Babbitt was the first to suggest that lumber workers use a circular saw instead of the two-man pit saw that only cut when pulled forward. She made a prototype and attached it to her spinning wheel in 1813. Babbitt's Shaker community didn't approve of filing a patent, but they took full advantage of the invention.

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