On Thu, 28 Nov 2002 07:12:02 -0000, "Jim Webster"
wrote:

irrigation based a one centre point?

Thanks Jim, that's what I'd thought but she'd remarked that was that possible at
the size of these crops.. Anyway, I've been going through various satellite
photography etc and multiple documents on Google and finally found an
explanation:

http://llk.media.mit.edu/projects/circles/flying.html

In brief:

"As for the circles in the Midwest, the story is quite simple. The irrigation
equipment tells the story. There is a long horizontal pipe with one end on
wheels and the other end on a rotating joint. As the pipe pivots, water drips
out of the pipe. The result is a circle, with the rotating joint at the center."

Problem solved thank-you!

Cheers,


Aido