Техническое чтение для энергетиков. Бухарова Г.П. - 75 стр.

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77
Marquis's lifetime, a machine for raising water 40 feet by steam pressure in mines.
Freed from the Tower by the Restoration in 1660, he was granted a patent by Parlia-
ment. The machine was exhibited as a model, but it was never executed in full size.
The Marquis used a cylinder into which steam was blown and then condensed; the
resulting vacuum would suck the cylinder full of water after a valve had been opened.
By blowing in some more steam the water could be forced out of the cylinder, and the
cycle restarted.
It may seem surprising that even in the seventeenth century, when the
superstitious and reactionary forces of medieval society had lost much of their hold
over the minds of men technical progress was so slow and inventive ideas so rare.
Even the Marquis of Worcester must have suffered from some feeling of guilt; he
wrote, in connection with his water-raising machine, that he prayed to Providence to
punish him for his arrogance and for yielding to evil temptations.
Perhaps the most interesting personality among the seventeenth-century steam-
engine inventors was Denis Papin, a French Huguenot, who studied medicine and
physics as a young man. He met the great Dutch scientist Christian Huygens, inventor
of the pendulum clock and author of the wave theory of light, in Paris and went with
him to the Hague. They worked together for eight years, and then Huygens
recommended the young Frenchman to Robert Boyle, the famous English physicist,
whose special field was the pressure of gases.
From 1675, Papin lived in Boyle's house in Pall Mall, London, and here he
made an invention which has only recently become popular in the kitchens of the
world – the pressure cooker. It was the outcome of his investigations into the nature
of steam.
Papin's 'bone-digester', as he called his machine, worked on the principle that
when water or juice is boiled in a hermetically closed vessel so that the steam cannot
escape, the pressure increases so much that the steam is heated far beyond the
boiling-point of water. The superheated steam helps to cook the food much faster and
more thoroughly than is possible in ordinary saucepans. 'I took beef bones that had
never been boiled, but kept dry a long time,' Papin wrote in the description of his first
experiment, 'and of the hardest part of the leg; these being put into a little glass pot,
with water, and inserted in the engine.' He also invented the safety-valve, a little
stopper with a weight attached, which closed a hole in the pot so long as the pressure
did not increase beyond a certain point; when it became too great it forced the stopper
out, and some steam escaped. This invention alone would have established his fame
in the annals of technical history, for it was the first automatic control device.
Papin introduced his bone-digester to the scientists of the Royal Society by
cooking a meal for them. It was excellent, and they enjoyed this 'scientific dinner', as
Papin called it, very much. But he made it plain to them that he regarded his bone-
digester merely as a stepping stone to the steam-engine which he hoped to build one
day.
A political event of great importance interfered with Papin's plan to return to
his native country and continue his work there. Louis XIV revoked the Edict of
Nantes, that solemn garantee assuring the Huguenots of religious freedom. Denis

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