Re: Has anyone designed hydraulic logic gates or a water-logic computer?

Hello Pat: Fluid logic has been around for some time. I saw an example of 
pneumatic logic intended for aircraft applications implemented circa 
1960s. Size, response time, and degree of complexity limit the 
practicalities of use. The history of logic gives some insight of the 
thought processes and the technology available to actualize the building 
blocks. Refer to the Britannica on the Internet at:
 http://www.britannica.com/bcom/eb/article/0/0,5716,119910+1+110690,00.html

To some extent fluidic logic finds application in today's technology as 
you can see at:
 http://www.britannica.com/bcom/eb/article/9/0,5716,35299+1,00.html

and at:
 http://www.whiteknightpumps.com/public/pneulog.html

As you can see there are specific applications that lend themselves to use 
fluids rather than electricity to perform logical functions. In special 
applications, modern logic includes the element of probability. Fuzzy 
logic was developed in USA but was heavily exploited by the Japanese 
industry, typically in control of appliances. If you are interested, refer 
to: 
 http://www.britannica.com/bcom/eb/article/index/1/0,8377,2211,00.html
 http://itri.loyola.edu/kb/c5_s4.htm

Your MAD.SCI Micro