Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: temp. calibration



On Mon, 6 Jan 1997, James Mclean wrote:

Michael N. Monce says:
calibration curve. More accuarcy can be obtained by correcting the data
for stem effects, etc. on the Hg thermometer.

This sounds interesting. What are "stem effects" on a thermometer?



These are corrections due to the stem of the thermometer not being
in contact with the same substance as the bulb. For example, if the bulb
is placed in water but the stem is in air, then the expansion of the Hg
will be different from the case when the entire thermometer was immersed.
Very similar to some of the corrections necessary when making pressure
measurements with a McLeod gauge. I don't recall details off the top of
my head; I think you would have to look back into the literature from the
50's. I do recall a paper I have buried somewhere from circa 1950 which
describes such corrections, especially in the Hg column on a McLeod gauge.


Mike Monce
Connecticut College