Today, we'll ride on a cable car. The University of
Houston's College of Engineering presents this
series about the machines that make our
civilization run, and the people whose ingenuity
created them.
Cable cars symbolize San
Francisco just as powerfully as the Eiffel Tower
symbolizes Paris. And rightly so! Where else have
you ever seen anything quite like them?
Cable cars were the clever answer to a problem. In
1870 neither electricity nor internal combustion
engines were in general use. The only obvious way
to power a streetcar was with horses or steam
engines. You could hardly put a fleet of mini-steam
locomotives on city streets. And that seemed to
leave only horses.
But then, in 1869, Andrew Hallidie visited San
Francisco. He watched four horses pulling a
streetcar up one of the city's murderous hills. One
of them slipped and went down. That started a chain
reaction. The rest of the horses fell, and the car
rolled down the hill dragging the panicked beasts
behind it.
Hallidie was a wire-rope salesman, and he saw an
alternative. You could cut a slot in the street and
run a moving wire cable through it. You could use a
stationary steam engine to drive a moving cable.
Then streetcars could be equipped with a mechanism
that dropped down into the slot to grasp the cable.
The idea wasn't entirely new. Something like it had
been tried in London and again in New Orleans. But
Hallidie organized a company; he solved the thorny
problem of making a really good quick-release
mechanism to grip the cable; and his new system
made its debut on precipitous Clay Street in 1873.
It wasn't long before 600 streetcars were riding a
network of 1¼-inch cables. The length of
some cables reached four miles, and they towed
streetcars all over San Francisco at a steady 9
mph.
The cable car system quickly spread all over
America. But the timing was bad. Edison and
Westinghouse were just coming out with electric
motors and public electric-supply systems. By 1890
-- in the blink of an eye -- cable cars were made
obsolete by the electric streetcar.
Most of the San Francisco cable lines were also
abandoned. But what originally drove Hallidie to
make those doughty little vehicles was their
special talent for scaling San Francisco's
seemingly vertical hills. So a few cable lines
survived -- survived the earthquake -- survived the
fire -- and they're still running. Of course, the
system has shrunk. It had 110 miles of track in its
heyday. Now it has less than 11 miles.
But what remains is a brief piece of Americana --
frozen in time. The cable cars are sustained by
sentiment, of course, but they also survive because
they were the right technology in the right place.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
