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C
elsius and Fahrenheit
are two
scales
used to
measure
temperature
. Both scales are based on the
freezing point
and
boiling point
of pure water at sea level. The
Celsius
scale has 100°
between the two points. The Fahrenheit scale has 180° between the freezing
point and boiling point.
Today most countries use the Celsius scale to measure temperatures. The
United States, however, still uses the Fahrenheit scale.
Daniel G. Fahrenheit
The Fahrenheit scale is named for German
scientist Daniel G. Fahrenheit. Fahrenheit
lived from 1686 to 1736. In 1714, he invented
the first mercury
thermometer
. He invented
a temperature scale to go along with it.
Fahrenheit’s thermometer marked normal
human body temperature as 98.6°F.
Fahrenheit thought he had found the lowest
possible temperature by mixing ice and salt.
He set the temperature of this
mixture
at 0°F.
Then he set the freezing point of water at 32°F.
He also set the boiling point of water at 212°F.
Anders Celsius
The Celsius scale is named for Anders Celsius,
a Swedish astronomer. Celsius lived from 1701
to 1744. In 1742, he created a temperature scale.
This scale used 0°C to mark water’s boiling point
and 100°C to mark its freezing point. A few years
later, another scientist changed Celsius’s scale
so that 0°C was the freezing temperature and
100°C was the boiling temperature. Celsius’s scale
was originally called the centigrade scale. It was
renamed in the 1940s to honor the inventor.
Celsius and Fahrenheit
Fahrenheit
Body
temp
98.6°
Room
temp
72°
Freezing
point of
water
32°
Celsius
Body
temp
37°
Room
temp
22°
Freezing
point of
water
0°
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