Branca's steam turbine. Artwork of the steam turbine proposed in 1629 by the Italian engineer Giovanni Branca (1571-1645). Branca published this design in his book Le Machine, but did not build a working model. Steam produced by the heat of a fire (left) would have rotated the turbine at centre. A system of gears would have transferred the energy to a set of pistons (right). These pistons would move up and down and grind wheat and other crops placed in the pestles.