> suppose if you could throw a switch and turn gravity on or off it would be a closer analogy I mean, you could, insofar as you can mechanically control the h

> suppose if you could throw a switch and turn gravity on or off it would be a closer analogy I mean, you could, insofar as you can mechanically control the height difference between the start and end of the maze. I think the real problem with the analogy was just that the hydrodynamic version wasn't a circuit in the sense that the electrical version was. The water just falls out of the system, so of course you can't control the pressure difference :) The exit of the hydrodynamic version should have been a (sealed) pipe that flows into an (open) buffer-chamber thatis after the maze; from which a pump operating on a control system then brings pumps water back to the (open) buffer-chamber that sits before the maze. Additionally, said pump's speed should be determined by the water-level imbalance between the two buffer-chambers, such that it's always trying to bring the two chambers into water-pressure equilibrium. (This pump is then a proper hydrodynamic analogue of a generator: two terminals with a constant height [voltage] differential between them, that pumps faster or slower [= varies current] to maintain the same potential difference in the system, whether the system is loaded or unloaded.) Then "turning off gravity" would just mean moving everything (the input buffer, maze, output buffer, and pump) from being in a vertically descending sequence (where the pump would be doing constant work to maintain the potential difference despite the "load"), to being on a flat plane (where everything would reach potential equilibrium, and the pump would then turn off.) And you could then represent AC flow, by just alternatingly raising and lowering the two chambers, and using a bidirectional pump.