"Reg Edwards" wrote in message
...

It later transpired in the laboratory that when water is under relatively
high pressure, such as at the bottom of the North Sea, when in contact
with
a thick polyethylene membrane it dissasociates into hydrogen and oxygen.

The very light element diffuses through leaving heavy oxygen on the
outside.
Thus, after a few years, the air-space on the inside becomes filled with
high pressure hydrogen.

What caused this "disassociation", and where did it happen? Just, I'd expect
the hydrogen to bubble off PDQ, assuming this process did occur. Also,
diffusion is the movement of something from a high to a low concentration,
assuming the mechanism is correct, I wonder how long before the
concentration would equalise (after all, the hydrogen around the cable must
have been in pretty low concentration.

Was the cable sealed at the ends? If so, what happened the gas (I assume
air) already in the cable?

If there's any copper on the outside then
presumably it becomes blackened by copper oxide.

How did get to the copper? If the insulation was all polyethylene, how did
it sometimes stop the oxygen and not others?

Is Dr Boris around?

--
Brian Reay
www.g8osn.org.uk
www.amateurradiotraining.org.uk
FP#898