text: In 1920, Nikola Tesla patented a valvular conduit or Tesla valve that works as a fluidic diode. It's a leaky diode, i.e. the reverse flow is non-zero for any applied pressure difference. Tesla valve also has non-linear response, as its diodicity has frequency dependence. It could be used in fluid circuits, such as a full-wave rectifier, to convert AC to DC.  
  In 1957, Billy M. Horton of the Harry Diamond Laboratories (which later became a part of the Army Research Laboratory) first came up with the idea for the fluidic amplifier when he realized that he could redirect the direction of flue gases using a small bellows. He proposed a theory on stream interaction, stating that one can achieve amplification by deflecting a stream of fluid with a different stream of fluid. In 1959, Horton and his associates, Dr. R. E. Bowles and Ray Warren, constructed a family of working vortex amplifiers out of soap, linoleum, and wood. Their published result caught the attention of several major industries and created a surge of interest in applying fluidics (then called fluid amplification) to sophisticated control systems, which lasted throughout the 1960s. Horton is credited for developing the first fluid amplifier control device and launching the field of fluidics. In 1961, Horton, Warren, and Bowles were among the 27 recipients to receive the first Army Research and Development Achievement Award for developing the fluid amplifier control device.