Hero of Alexandria conceived many hydraulic machines. An eolipile, also known as a Hero’s engine, is a simple bladeless radial steam turbine which spins when the central water container is heated. Torque is produced by steam jets exiting the turbine, much like a tip jet or rocket engine. In the 1st century AD, Hero of Alexandria described the device, and many sources give him the credit for its invention. The eolipile Heron described is considered to be the first recorded steam engine or reaction steam turbine. The name – derived from the Greek word Αἴολος and Latin word pila – translates to “the ball of Aeolus”, Aeolus being the Greek god of the air and wind.
