Elevators

The long history of elevators includes the construction of the pyramids, the experiments of Archimedes, the platforms that raised gladiators to the floor of the Roman Coliseum, and the passenger elevators of King Louis XV of France and Empress Maria Theresa of Austria. The modern history of elevators begins in 1853, when Elisha Graves Otis of Yonkers, New York, [Page 240]invented an elevator safety device that stopped cars whose hoisting cables had snapped from falling to the bottom of the shaft. Otis marketed his elevators and their safety breaks aggressively. P. T. Barnum gave Otis a space at the center of New York's Crystal Palace in 1854, where he demonstrated his device by slashing the rope of his demonstration elevator, falling a few inches, and calling out that all was safe.

New Yorkers and the residents of other large cities did not immediately warm to elevators. The first machine solely devoted to passenger service, installed in 1857 in the Broadway department store of merchants E. V. Haughwout and Co., soon went out of service because it made customers nervous. But in the late 19th century, elevators transformed the landscape and social life of industrial cities. They had two basic effects on society. First, elevators and the advent of structural steel allowed architects to build higher than ever before, creating denser residential neighborhoods and commercial districts and offering the necessary tools to build and run skyscrapers. Second, elevators increased the tendency toward segregation of buildings and neighborhoods by class. Before, buildings with multiple tenants could not rent upper floors at the same rate as lower ones, because the walk up made them less valuable. The new mode of conveyance ended this problem, spurring the growth of luxury apartment houses and office towers with rents uniform enough to keep out people below a certain income.

Advances in the technology of elevators generally have run to three purposes: greater speed/height, increased safety, and decreased reliance on human labor. The shift from steam power to hydraulics in the 1870s and electricity in the 1890s increased the speed of elevators and the heights of their buildings (although hydraulics dominated tall buildings until the introduction of gearless traction elevators in 1902). Following Otis's invention of 1853, his company and competitors came out with an endless stream of safety improvements—systems of multiple cables, the “air-cushion” device (which locked rapidly, compressing air under a falling elevator car until resistance slowed it to a gentle stop), interlocks to stop motion until the car doors were closed, automatic car leveling, and electric eyes to protect passengers' limbs. Other inventions, such as Muzak, calmed passengers' anxieties about vertical travel without actually increasing safety.

Clearly, some safety devices also aided the shift to full automation, but the crucial technological advance involved the slow invention of elevators smart enough to deliver many passengers to different floors. Automatic, push-button elevators dated to 1892, but early models could not handle more than one call at a time and so were limited to short, mostly residential buildings. A concerted effort to develop sophisticated automatic elevators did not begin until the mid-20th century, when operators' unions drove up the price of labor and a cultural rage for automation swept America. The “Autotronic” and “Selectomatic” systems unveiled by Otis and Westinghouse in 1948 ran unstaffed elevators electronically and shifted their traffic schedule without human supervision during the course of the day; subsequent advances include Otis's Elevonic 101 system of 1979, the first method of elevator control run completely through microprocessors, and the use of fuzzy logic to increase efficiency in Japanese elevator systems in 1992.

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