Homebrew Drum Computer Delay Lines

I've come across a reference to a reverb unit made with a garden hose, speaker, and microphone. Would something as bone-headed as this work as a data delay line? I've read that mercury was used in delay lines because it was a better impedance match with quartz transducers, but wouldn't water work nearly as well? Everything would need to be kept at a constant temperature, and no doubt there would be some dispersion of the compression waves. It's my understanding that a lot of materials were tried for delay lines, but that mercury was the "best." Magnetostrictive delay lines are attractive, though I hear they are more than a little microphonic. I notice that most magnetostrictive delay line designs use the transducers to generate torsional waves, which apparently suffer less from dispersion and have a slower propagation speed to boot. The pictures I've seen show the transductive materials spot welded to the delay wire such that they twist the wire when a magnetic pulse is applied: http://www.science.uva.nl/faculteit/museum/delayline.html Does anybody know how well plain nickel wire would work OK, or would some more exotic like Terfenol-D be required? The delay wire itself need not be magnetostrictive; it's just the storage medium. -Bobby