Today, an uplifting tale of a recently forgotten
technology. 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.
The Smithsonian Institution
acquired a small hydraulic elevator in 1984. It
came from a five-story Boston house. It had been
installed there in 1902, and it ran until it jammed
40 years later. Curator Robert Vogel describes this
lift, along with the whole forgotten technology of
early domestic elevators.
The electric elevators that we ride appeared in the
1880s, right on the heels of public electric power.
And they made it possible to build really tall
buildings. But serious elevator-building had
started 50 years before that. The first powered
elevators appeared around 1830, when factories
began using their central power systems to drive
rope-and-pulley lifts.
Those early systems couldn't serve businesses and
dwellings. They needed independent power supplies.
Steam engines were the court of first resort, but
they were cumbersome. Someone had to be on duty,
stoking a boiler and lubricating valves.
An even more pernicious problem had to be solved
before the public was going to accept any kind of
elevator. People wanted some guarantee that the cab
wouldn't fall like a stone if the power failed or a
rope broke. Potential buyers looked at a small room
riding on the end of spindly cable, and it reminded
them of the hanging sword of Damocles.
Elisha Otis, whose name still decorates elevators
today, solved the safety problem in 1854. He
invented a foolproof automatic braking system.
After that, at least for a time, steam elevators
became as popular as any system that cumbersome
could become.
Meanwhile, high-pressure public water systems were
being put in after the Civil War, and people found
two ways to put them to use: You could put an
elevator at the end of a two or three-story
plunger, but you usually wanted to ride higher than
that. In the more useful system, a large hydraulic
piston drove rope through a series of pulleys. A
five-foot hydraulic piston stroke lifted an
elevator fifty feet or more, and the power simply
came out of the central water main.
So, at the same time electric elevators were making
it possible to erect skyscrapers, these hydraulic
lifts appeared in the high-rise houses that were
springing up in the crowded Eastern cities. In 1901
and 1902, 68 of them were installed in Boston
alone.
The Smithsonian's lift shows us a technology that
most of us aren't even aware of -- one that's long
since been overtaken by cheaper electric systems.
But it was once a clean, ingenious, and wonderfully
simple solution to a hard problem that arose as our
crowded cities began to grow upward.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
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