The message
from "Phil L" contains these words:

The pipe contains 15 mm of water, encased in a 1 mm copper sheath, the tap
contains 25mm of water encased in a 10mm brass sheath, which is going to
freeze first?

The water in the tap.

:: Air is not a good conductor, nor does it have a high energy
:: potential.
::
:: However, leaving the tap open will certainly lessen the liklihood
:: of a burst, especially if the freezing is very slow. Ice at or near
:: freezing-point melts readily when under pressure, resulting in a
:: certain amount of it being pushed through the tap as ice, and once
:: unconstricted, the fluid fraction immediately freezes, making it
:: appear as if the ice has been pushed out as a lump.

Like I said, it expands out of the open tap.

Only under *VERY* slow freezing conditions. A hard frost, and the water
in the tap freezes hard, and the expansion takes the easier way out -
through the copper pipe.
God sends the meat, the Devil sends the cooks.

--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
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