For centuries people have been thinking of ways to move heavy loads to higher places. As far back as 236 B.C., Archimedes developed a weight-lifting device operated by ropes and pulleys. Before him the Egyptians used hoists to build the Pyramids, the largest of which stands over 500 feet (150 meters) tall and has many building blocks weighing more than 200,000 pounds (90,000 kilograms) each. However, none of these early efforts were considered safe for lifting people because of one major flaw -when the hoisting rope broke, the lift fell.
It was not until 1852 that Elisha Graves Otis (1811–61) built a "safe" elevator. It was designed with a safety brake to prevent the hoist platform from falling even if the cable or rope holding it broke. A cable break caused springloaded bars on the elevator to snap out and hook onto the toothed guiderails in the elevator shaft. This locked the platform securely in place and prevented it from falling.
Otis successfully demonstrated his invention at the 1854 World's Fair in New York City. With safety guaranteed, people were willing to ride in elevators. The safe passenger elevator was an important step in the development of tall, multistory buildings. First known as cloudscrapers, and later called skyscrapers, these buildings would forever change the appearance of cities.
In 1857, Otis installed the world's first passenger elevator in a five-story New York City building. At that time, electric power was not widely available. Since few buildings had a source of power, Otis adapted a steam engine to power his elevators. The first electrically driven elevator was installed in a New York City building in 1889.
It was not until 1852 that Elisha Graves Otis (1811–61) built a "safe" elevator. It was designed with a safety brake to prevent the hoist platform from falling even if the cable or rope holding it broke. A cable break caused springloaded bars on the elevator to snap out and hook onto the toothed guiderails in the elevator shaft. This locked the platform securely in place and prevented it from falling.
Otis successfully demonstrated his invention at the 1854 World's Fair in New York City. With safety guaranteed, people were willing to ride in elevators. The safe passenger elevator was an important step in the development of tall, multistory buildings. First known as cloudscrapers, and later called skyscrapers, these buildings would forever change the appearance of cities.
In 1857, Otis installed the world's first passenger elevator in a five-story New York City building. At that time, electric power was not widely available. Since few buildings had a source of power, Otis adapted a steam engine to power his elevators. The first electrically driven elevator was installed in a New York City building in 1889.
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