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Here's the original patent for 'revolving stairs' from 1859: https://patents.google.com/patent/US25076A/en https://patents.google.com/patent/US25076A/en
by helloplanets 2y ago
Here's the original patent for 'revolving stairs' from 1859: https://patents.google.com/patent/US25076A/en https://patents.google.com/patent/US25076A/en