Техническое чтение для энергетиков. Бухарова Г.П. - 22 стр.

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A greater scientist than he, Alessandro Volta of Pavia, solved the mystery and
found the right explanation for the jerking frogs. Far from being the 'primary source
of life', they played the very modest part of electric conductors while the steel of the
scalpel and the zinc of the plate were, in fact, the important things. Volta showed that
an electric current begins to flow when two different metals are separated by moisture
(the frog had been soaked in salt water), and the frog's muscles had merely
demonstrated the presence of the current by contracting under its influence.
Professor Volta went one step further – a most important step, because he
invented the first electrical battery, the 'Voltaic pile'. He built it by using discs of
different metals separated by layers of felt which he soaked in acid. A 'pile' of these
elements produced usable electric current, and for many decades this remained the
only practical source of electricity. From 1800, when Volta announced his invention,
electrical research became widespread among the world's scientists in innumerable
laboratories.
EARLY HISTORY OF ELECTRICITY
Let us now turn our attention to the early facts, that is to say, let us see how it all
started.
History shows us that at least 2,500 years ago, or so, the Greeks were already
familiar with the strange force (as it seemed to them) which is known today as
electricity. Generally speaking, three phenomena made up all of man's knowledge of
electrical effects. The first phenomenon under consideration was the familiar
lightning flash –a dangerous power, as it seemed to him, which could both kill
people and burn or destroy their houses. The second manifestation of electricity he
was more or less familiar with was the following: he sometimes found in the earth a
strange yellow stone which looked like glass. On being rubbed, that strange yellow
stone, that is to say amber, obtained the ability of attracting light objects of a small
size. The third phenomenon was connected with the so-called electric fish which
possessed the property of giving more or less strong electric shocks which could be
obtained by a person coming into contact with the electric fish.
Nobody knew that the above phenomena were due to electricity. People could
neither understand their observations nor find any practical applications for them.
As a matter of fact, all of man's knowledge in the field of electricity has been
obtained during the last 370 years, or so. Needless to say, it took a long time before
scientists learned how to make use of electricity. In effect, most of the electrically
operated devices, such as the electric lamp, the refrigerator, the tram, the lift, the
radio, and so on, are less than one hundred years old. In spite of their having been
employed for such a short period of time, they play a most important part in man's
everyday life all over the world. In fact, we cannot do without them at present.
So far, we have not named the scientists who contributed to the scientific
research on electricity as centuries passed. However, famous names are connected
with its history and among them we find that of Phales, the Greek philosopher. As
early as about 600 B. C. (that Is, before our era) he discovered that when amber was

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