Today, let's look at steam engines in
eighteenth-century England. The University of
Houston's College of Engineering presents this
series about the machines that make our
civilization run, and the people whose ingenuity
Steam engines were England's
gift to the world in the eighteenth century. Thomas
Savery began it all with his steam pump in 1698. He
was followed by Thomas Newcomen's first real steam
engine in 1711. When James Watt sold his first
engine in 1769, steam engines had been around for
seventy years. Almost 600 of them had been built.
What Watt did was to make improvements that left
steam engines four times more efficient. His first
engines put out only about six horsepower -- not
much more than the first Newcomen engines -- but
they were smaller and they ate far less coal. And
in less than 20 years he'd increased the output to
as much as 190 horsepower.
In those days 190 horsepower would by no means fit
under the hood of a car. Those early engines were
enormous. The cylinders of the old Newcomen engines
were from two to ten feet in diameter. A Newcomen
engine was a two-story structure. Watt's engines
were more compact, but their cylinders were still
between one-and-a-half and five feet in diameter.
Historians Kanefsky and Robey tell us that, as good
as they were, Watt's engines didn't dominate
production. By the end of the century, over 2000
steam engines had been built in England, and fewer
than 500 of them were Watt engines.
Actually, steam engines never did become the major
power source during the eighteenth century. Most of
the power still came from waterwheels and
windmills. Steam-engine factories never did produce
more than a few hundred total horsepower per year.
But two things were happening: Steam power picked
up those specialized tasks that were absolutely
essential for the industrial revolution -- like
pumping water out of mines so we could have the
coal and metals we needed. And steam power was the
basis for the heavy power industries that so
changed nineteenth century life.
By 1800 the total power capacity of all the steam
engines ever built was about the same as one of our
larger diesel engines today. They didn't change the
English countryside overnight. But they were the
stalking horse of the greatest revolution the world
had ever seen -- the agents of changes that far
outstripped anything their makers had ever thought
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
Kanefsky, J.,and Robey, J., Steam Engines in
18th-Century Britain: A Quantative Assessment,
Technology and Culture, Vol. 21, No. 2, April,
1980, pp. 161-186.
This episode has been greatly revised as Episode 1440.
From Steam Engines Familiarly
Savery's 1698 Steam Pump
From the 1832 Edinburgh
Newcomen's Atmospheric Steam Engine