Just realized that this is in response to a rather old post (12/1). Here is
what prompted this:

"Todd H." wrote in message ...
"Mark" writes:
if you leave the top open so the water can expand, won't that work
ok?

Unfortunately for this problem, water freeze from the top down.

This property of water, however is fortunate overall, since none of us
critters would be here if water froze from the bottom up.

--
Todd H.
http://www.toddh.net/
______________________________

"Tomes" wrote in message
ink.net...

"Mark" wrote in message
oups.com...
yeah I remember reading that once, I don't recall why...enlighten us...

Mark

So life can happen underneath when the top is frozen. Useful in fresh
water
environments.