A FLUIDYNE STIRLING CYCLE HOT AIR ENGINE DESIGNED BY HARWELL IN THE EARLY 1970S AS A LOW TECH EASILY MADE WATER PUMP WITH NO MOVING PARTS FOR MAJORITY WORLD MANUFACTURE

A FLUIDYNE STIRLING CYCLE HOT AIR ENGINE DESIGNED BY HARWELL IN THE EARLY 1970S AS A LOW TECH EASILY MADE WATER PUMP WITH NO MOVING PARTS FOR MAJORITY WORLD MANUFACTURE,
consisting of a glass vessel with a U tube emerging from the closed top. One side of the U is heated by a candle and the other cooled. With the introduction of a long tube, the harmonic column frequency ensures that the two columns of water move up and down opposite to one another, thus displacing the air from the hot to the cool side. By the insertion of glass ball valves, water is sucked from the reservoir and emitted from the swan neck,