Sounds a wee bit like those little flash steam model boats we used to make
as kids.
A U shaped bit of copper tubing would project from the stern of the boat
just on the water line. And would run slightly down for about 3" to a meths
burner.
After heating up, the boat would be put into the pond or whatever, a little
water would enter the pipe and run down to the hot part where it would be
vapourised causing a jet of steam to come out of the pipe, propelling the
boat along with a series of Put Put Puts
Good fun, I think I might go and make one now for the Kids!
Patrick

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In article , "malcolm"
wrote:


you might find this interesting.
http://www.pursuitdynamics.com/default.asp
radical new form of water pulse Jet for Boats.
regards malcolm