The Romance of Modern Chemistry
Forfatter: James C. Phillip
År: 1912
Forlag: Seeley, Service & Co. Limited
Sted: London
Sider: 347
UDK: 540 Phi
A Description in non-technical Language of the diverse and wonderful ways in which chemical forces are at work and of their manifold application in modern life.
With 29 illustrations & 15 diagrams.
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CHAPTER XVI
BELOW ZERO
IT is an old tale that Fahrenheit took as the zero of
his thermometer the lowest temperature which was
observed by him at Dantzic during the winter of
1709, and one of his contemporaries remarks that Nature
never produced a cold beyond zero. This is quite a
mistaken view, for plenty of cases are on record in which
considerably lower temperatures have been observed as
the direct result of natural cold. By artificial methods
it is possible to realise a much greater degree of cold,
and within the last ten years temperatures of about
— 400° Fahrenheit have been reached. As the mercury
in our thermometers freezes at about —40° Fahrenheit,
the reader will see that a lowering of the temperature
to — 400° brings us to altogether new conditions.
The way in which chemists and physicists have gradu-
ally pushed forward into the region of low temperatures
is very remarkable, and their discoveries are not only
of fascinating interest to the student of Nature, but
have in some cases proved of practical and commercial
value. The ambition to get “farthest north” has led
to many thrilling adventures, but the Arctic exploration
carried out recently in the laboratories of England and
the Continent is not a whit less romantic.
The first step in the direction of low temperatures
is taken when we can start with substances at the
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