On Tue, 27 Apr 2004 10:50:04 -0700, Jim Kelley
wrote:



wrote:

On Mon, 26 Apr 2004 09:57:59 -0700, Jim Kelley
wrote:

How so?

Pascal's law.

Are you implying that any and every column of mercury must obey Pascal's
law?

Any column of any liquid should. Would you care to cite a
counter example?

You already cited one. (You can't apply pressure to a confined fluid if
it's sealed in an incompressible container.)

73, ac6xg

OK, nice specious argument. You can't have read this far in
the thread without understanding the intended parameters. And since
you seem to be referring to the thermometer, pressure could indeed be
applied. In absolute terms, any container can be compressed, however
slightly. In addition, pressure can be applied without compression by
application of heat or of cold, depending on relative coefficients of
thermal expansion.

Old science class demonstration -- completely fill a heavy
pipe, capping both ends, with a substance; heat the pipe with a torch
and it explodes; toss the pipe into a container of dry ice and it
explodes. What is the mystery substance? It turns out to be water at 4
degrees Centigrade.

Finally, I strongly suspect the "column" of mercury in a
thermometer does indeed obey Pascal's law, but it's effect is
overshadowed by the much stronger effects of temperature and
capillarity.