Техническое чтение для энергетиков. Бухарова Г.П. - 19 стр.

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21
process, always getting similar results.
On placing an unmagnetized iron bar near a strong magnet, we magnetize it.
Rubbing the magnet is not required for that process. In other words, our iron bar has
been magnetized by the strong magnet without rubbing it.
EARLY DAYS OF ELECTRICITY
There is electricity everywhere in the world. It is present in the atom, whose
particles are held together by its forces; it reaches us from the most distant parts of
the universe in the form of electro-magnetic waves. Yet we have no organs that could
recognize it as we see light or hear sound. We have to make it visible, tangible, or
audible, we have to make it perform work to become aware of its presence. There is
only one natural phenomenon which demonstrates it unmistakably to our senses of
seeing and hearing – thunder and lightning; but we recognize only the effects – not
the force which causes them.
Small wonder, then, that Man lived for ages on this earth without knowing
anything about electricity. He tried to explain the phenomenon of the thunderstorm to
himself by imagining that some gods or other supernatural creatures were giving vent
to their heavenly anger, or were fighting battles in the sky. Thunderstorms frightened
our primitive ancestors; they should have been grateful to them instead because
lightning gave them their first fires, and thus opened to them the road to civilization.
It is a fascinating question how differently life on earth would have developed if we
had an organ for electricity.
We cannot blame the ancient Greeks for failing to recognize that the force
which causes a thunderstorm is the same which they observed when rubbing a piece
of amber: it attracted straw, feathers, and other light materials. Thales of Miletos, the
Greek philosopher who lived about 600 В. С, was the first who noticed this. The
Greek word for amber is elektron, and therefore Thales called that mysterious force
'electric'. For a long time it was thought to be of the same nature as the magnetic
power of the lodestone since the effect of attraction seems similar, and in fact there
are many links between electricity and magnetism.
There is just a chance, although a somewhat remote one, that the ancient Jews
knew something of the secret of electricity.
Perhaps the Israelites did know something about electricity; this theory is
supported by the fact that the Temple at Jerusalem had metal rods on the roof which
must have acted as lightning-conductors. In fact, during the thousand years of its
existence it was never struck by lightning although thunderstorms abound in
Palestine.
There is no other evidence that electricity was put to any use at all in antiquity,
except that the Greek women decorated their spinning-wheels with pieces of amber:
as the wollen threads rubbed against the amber it first attracted and then repelled
them – a pretty little spectacle which relieved the boredom of spinning.
More than two thousand years passed after Thales's discovery without any
research work being done in this field. It was Dr. William Gilbert, Queen Elizabeth

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