The barometer must be hung on a wall or a post. This instrument is an alcohol-in-glass thermometer
(the alcohol is coloured red) with a range of minus 10 to plus 110 degrees Celsius. Each graduation
is 1 degree. Other thermometers use mercury - a silvery-coloured liquid - to measure temperature.
- Hold the thermometer gently but securely near the 20-degree Celsius mark. If you are measuring
air temperature, don’t hold the thermometer at the ‘red’ end - that would give a false reading. Your
skin temperature is generally warmer than the air temperature.
- Take the thermometer to where you want to measure the air temperature. Hold it or hang it up
(there is a loop at the top of the instrument) on a wall or a tree, for instance, for at least five
minutes before taking a reading.
- Return the thermometer to its protective cardboard case when you have finished.
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