David Unaipon (1872 – 1967), a Ngarrindjeri man of the Coorong region of South Australia, was an author, inventor, evangelical preacher, and political activist. His many significant accomplishments during a period that book-ends Australian federation challenged the prejudiced stereotypes held about Aboriginal people.
Unaipon spent much of his life reading science books and was particularly fascinated by perpetual motion. His deep understanding of the fundamental principles of physics led to his most successful invention, a sheep-shearing handpiece that converts curvilinear motion into the straight-line movement. This design, partially patented in 1909 greatly improved the efficiency of the cutting blades and is still in use today.
His helicopter design in 1914, based on the aerodynamics of the boomerang, pre-dates the manufacture of the world’s first ‘hovering aircraft’ by 25 years.
His research into the polarisation of light points to him also being a pioneer in the field of photonics. In an interview published in the Daily Herald (Adelaide, SA 1/6/1914) he said; “We are gradually coming to the age when we might expect to be able to hurl electricity, like Nature does, for instance, in the shape of lightning.”
Unaipon’s legacy has been re-examined in more recent times, and his image along with his shearing shears design has been on the Australian $50 banknote since 1995.