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Elevators

June 20, 2000

A public radio commentary

What is the safest way to travel? Its a method that every year moves forty-five billion passengers a distance of one and a half billion miles - and with only about fifteen deaths.

It is an elevator.

Now its useful only, of course, for traveling up and down a building; although, according to insurance companies, its five times less hazardous that climbing steps. Elevator were not always this safe; in the early 1800s people used them only for moving freight - no reasonable person would ride on such a thing - it was not uncommon to hear of a heavily loaded elevator plummeting and killing everyone aboard.

The key innovation in making elevators appealing to people came from Elisha Graves Otis - a name still seen on millions of elevators. In 1853, at the Crystal Palace Exposition in New York, Otis, dressed in tails and a top hat, stepped into one of his elevators, filled with boxes and barrels, and was hoisted forty feet above the ground. When the elevator stopped Otis ordered a workman with an ax to cut the hoist cable supporting the elevator. The crowd watched in horror as the platform jerked and then ... nothing happened: Otis and his elevator platform stayed right where they were.

As the stunned crowd stared Otis took off his top hat, bowed, and made his sales point, he cried out "All safe, ladies and gentlemen, all safe." A new rope was attached and the elevator lowered safely to the ground. Otis called this his "safety elevator." He built a spring loaded lever into the its floor. The hoist cable kept the lever retracted, but if it were cut and tension lost the spring instantly thrust the lever into the shaft stopping the elevator's descent. Today this same basic device still keeps elevators from tumbling down their shafts.

In spite of this dramatic demonstration it took Otis three years to sell a passenger elevator. His first was installed in a five-story china and glass emporium on Broadway in New York. It whisked passengers up at forty feet a minute - an elevator this slow would take thirty minutes to reach the top of Chicago's Sears Tower, a trip made in less than a minute with today's elevators. Otis' elevator company succeeded, unlike his previous business ventures partly because it became crucial in accommodating the large urban growth of the last two decades of the 1800s.

Because of a huge influx of workers house prices in cities skyrocketed - there simply wasn't enough land to go around. Elevators made apartment buildings attractive, which in the past had been segregated by economic class: Wealthy families lived on the lower few floors so they didn't have to climb many stairs, while poor families were usually confined to the basement or the upper floors.

The elevator allowed taller buildings to be built and, in a sense, democratized apartment buildings allowing all floors to be equally attractive. Today, of course, elevators are not viewed as a force for democracy, or even as a mechanical miracle that saves lives. Like all successful technological innovation our interest in them has been reduced to social psychology; to a set of rules governing our behavior in elevators - conversations should be whispered, eyes focused forward toward the door, and strangers should keep a distance from one another - all because Elisha Graves Otis attached a spring and a lever to bottom of an elevator.

Copyright 2000 William S. Hammack Enterprises