Heliograph, TIL "Australian-Aboriginal man David Unaipon is known for his contributions to science and the #Aboriginal people. His inventions include a tool for sheep-shearing, a centrifugal motor, a multi-radial wheel and mechanical propulsion device. #Unaipon appears on #Australia's $50 note." :akko_fistup:
https://en.m.wikipedia.org/wiki/Timeline_of_Australian_inventions