> Which leads me to a question. I see people here stating "My
> humidity is X%" - what I want to know is how do you measure the
> humidity to get a number like X?
'Officially' you use a wet/dry bulb thermometer - two thermometers,
one of which has a wick and a water reservoir to keep the 'bulb'
surrounded by the moist wick. The evaporation of the water (more
the lower the humidity it) cools this one. You take the temperature,
and the difference between the two readings, and look it up in a
table to get the humidity.
For less fuss, there are gauges which give a direct reading - they
must use a strip of something which reacts to moisture. I have one
together with a barometer in the house - it's reading 43% at the
moment (today was cold and dry here in England).
-- Clarke Brunt (clarke@brunt.demon.co.uk)