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Re: absolute pressure



Why do they call it a "mercury" barometer?

as aposed to the original Torricelli barometer? (water) http://www.islandnet.com/~see/weather/history/barometerhistory1.htm

Until the advent of S.S. electronics, neroid barometers were
significantly more efficient (cost per performance) than the mechanical
ones (aneroid). Geologists use(d) aneroids for mapping. Their
resolution is ~ one foot. (memory) The pilot on this list can compare
this to his. [What does he use now?]

bc whose aeronautical altimeter was "spot on" with the road signs on the
way to skiing, until he dropped it, damn!

Herbert H Gottlieb wrote:

On Wed, 05 Jun 2002 07:27:57 -0500 Brian Whatcott <inet@INTELLISYS.NET>
writes:

Where can one purchase a "mercury barometer" that does not
require any air to operate?
*******************
Taking up Herb's question, the mercury barometer absolutely
requires the absence of air in the Torricellian vacuum of the
overhead
space.
*******************

OK! Now let's carry this insignificant dialog one step further
......................

Why do they call it a "mercury" barometer?
After all, it is made almost entirely of glass with a bit of metal and
leather
here and there. If fact a mercury barometer is sometimes sold without
any
mercury at all and the purchaser has the option of adding. or not adding
mercury later.

BTW.Do you remember how can you find the height of a building using a
mercury barometer???

Herb Gottlieb from New York City
(Where we have found ingenious ways to measure the heights of our
buildings with mercury barometers)