Техническое чтение для энергетиков. Бухарова Г.П. - 76 стр.

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78
Papin had become an exile.
At this turning-point in his life, a German Protestant prince offered him a chair
at the University of Marburg. Papin accepted, hoping that under the protection of an
enlightened ruler he would be able to develop his steam-engine; his pet idea was that
of driving a ship with it 'against the wind'.
He built an experimental model at Marburg. It was a complicated and rather
clumsy machine whose energy derived more from atmospheric pressure than from the
power of the expanding steam; a workman had to solve a fire-box under it at certain
intervals to produce the steam, and remove it again to cause condensation. But it had
one ingenious feature which pointed the way to a really efficient prime mover: Papin
used the cylinder and piston of a pump in his design. This, above all, was Papin's
most valuable contribution to the development of the steam-engine.
He described his invention in a pamphlet published in 1690, hopeful that the
whole world would acclaim him as its benefactor. But the world seemed to have little
use for the steam-engine; only one inventor, an English captain by the name of
Thomas Savery, carried out some of Papin's ideas and took out a patent for a water-
lifting machine.
So Papin decided to return to England, where he hoped to find more support.
He bought a boat and fitted it with paddle-wheels, later to be driven by steam power;
but as a kind of propaganda act Papin intended to propel it by means of hand-cranks
from Marburg all the way to England, with his wife and his numerous children on
board.
He did not get very far. A few miles down the river, at the next town, the
watermen's guild barred the way to the strange vessel full of foreigners. There was a
tussle, the irate scientist tried to push on, but the watermen pulled the boat on land
and cut it to pieces with their pickaxes.
Desperate and without a penny to his name Papin arrived back in London. In
vain he tried to get the Royal Society
to help him build his steam-engine, or at least:
compare his designs with those of Savery. In the end he had to struggle for a bare
livelihood. His traces are lost in the slums of London; the last document in his
handwriting, a letter to a friend, dates June 1712, closes thus:
'I am in a melancholy situation; in spite of all my effort I only bring down
enmity on myself. But I have no fear.'
In the same year an ironmonger and Baptist preacher from Dartmouth, Thomas
Newcomen, completed his own steam-engine after years of experimenting with
Savery's pumps. The only place where such an engine was urgently needed was in
Britain's mines, which filled with water faster than it could be cleared out. Savery had
used the method of creating a partial vacuum in the cylinder by dashing cold water on
its outside, thus causing the steam inside to condense; Newcomen, however, sprayed
the cold water directly into the steam-filled cylinder to create a vacuum so that the
atmospheric pressure forced the piston down. From the time of Savery's death in
1715, Newcomen controlled the manufacture of steam pumps in Britain for a good
many years. Some were exported to the Continent although they wasted an enormous
amount of coal and had to.have constant attention.

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