At 04:44 PM 2001-11-29 +0300, Eric Scace wrote:
> A stretch of garden hose (or several hoses connected together, or any
> other length of tubing) makes an excellent elevation
>measuring device. Lay it out along the ground with the ends sticking up
>in the air. Water inside the tube will be at the same
>elevation at both ends of the tube. Measure the height of the water in
>each end above the ground and you will be able to determine
>the difference in ground elevation. (You might need a ladder at one end
>if the ground drops off quickly!). It only takes one
>person (with a bit of care) to make the measurement.
>
>-- Eric K3NA
This is gennerally a very good method. HOWEVER, watch for heating along
the length of the hose. If one end is hotter than the other, such as, most
of the hose is in the shade and part in the blazing sun, the heated water
becomes lighter than the cooler water. Most of the time this does not
matter, but I had one condition just over 50ft where if I did it in the
forenoon when all the hose was in the sun VS in the evening when part was
in the sun, I observed two different elevations, delta 1/2 - 3/4 inch.
Chris opr VE7HCB
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