Temperature monitoring systems: The hygrometer evolution.
Hygrometers are instruments used to measure the amount of water
in the air, which have been around since the mid 1700s. The ways
to actually do the measuring have evolved since then so that
today in addition to the hair hygrometer, thermohygrographs and
electronic hygrometers are used. Very inexpensive hygrometers
are used as barometers in meteorology to monitor and predict
weather changes, however this instruments are not accurate
enough for museums and art galleries.
Museums and art galleries use very accurate hygrometers to
monitor the amount of moisture in the indoor environment over a
long period of time. Most museums monitor these conditions 24
hours a day since the wrong moisture level can damage valuable
paintings and other works of art. They tend to use the more
accurate psychrometers and electronic hygrometers.
Temperature, expressed in degrees Celsius (