Dear Robert L Judge

I am a farmer in New Zealand and today I have been trying to siphon water 
from
a reservoir, over a ridge about 14m higher than the water level in the
reservoir, and down the hillside on the other side to a level about 10m 
lower
than the reservoir water level. The horizontal distances involved are about
100m from the ridge to the reservoir and from the ridge to the outfall.

We failed, even though we believe that we had filled the pipe full. We used
both 15mm and 20mm inside diameter pipes in our testing.

We wondered if there was a limit on the height of the lift from the 
reservoir
level to ridge.

Can you advise us please why you think our system failed and whether you 
think
that the pipe diameter has an influence.

Bob Wakelin
Farmer
Rangiwahia
New Zealand

Yours faithfully