Monday, October 28, 2013

GOING DOWN?


For centuries, the drudgery of having to climb long flights of stairs ensured that buildings were seldom more than six or seven stories high. The least desired apartments in ancient Rome were those on the top floor--just the opposite of our modern preferences. This held true until the late nineteenth century, when elevators began to be incorporated in tall buildings. 

Elisha was here.
Yet the elevator isn’t  quite as modern an invention as you might think. The Roman architect Vitruvius reported that Archimedes built his first elevator around 236 B.C.  In 1743, Louis XV commissioned a personal lift to link his apartment in Versailles with that of his mistress.  Eighty years later, the painter Thomas Horner and the architect Decimus Burton collaborated on an “ascending room” that hoisted visitors to a 37-meter high platform from which they could view the London skyline.

Still, the general public remained understandably wary of such devices, since a single broken rope could send the hapless passeners plunging to their doom. This attitude began to change in 1853, when Elisha Graves Otis demonstrated his “safety elevator” featuring the first failsafe means of arresting the elevator’s fall should a support rope fail. Otis’s elevator went a long way toward easing public anxiety about riding on such contraptions, and in 1857 Otis installed the first public elevator in a five-story department store in New York, and in 1861 he patented an elevator powered by steam. Hydraulic and electric elevators eventually followed, finally obviating the need to climb endless flights of stairs in tall buildings.

Yet Otis’s product (which, in fairness, was greatly refined by a number of lesser-known inventors) would have remained a curiosity were it not for some concurrent trends that made taller buildings both more economicallydesirable and cheaper to build. By the last decades of the nineteenth century, the price of downtown land in rapidly expanding cities such as New York and Chicago began to skyrocket. This put pressure on developers to pack more building volume into the same amount of real estate, which meant only one thing: Build taller buildings. 

Yet the push to pile up more and more stories presented a problem of another sort. Large buildings of the late nineteenth century were still built of masonry and required thicker and thicker walls the taller they became. As an example, one of the last tall masonry buildings of the era, Chicago’s Monadnock Building, carried its seventeen stories on ground floor walls six feet thick. This kind of ponderous and expensive structure simply wouldn’t do if tall buildings were to become practical. Fortunately, a new building material--steel--solved this problem just in time. Steel was enormously strong in relation to its mass, meaning that even the tallest building could now be supported by a relatively wispy “skeleton frame” of girders rather than by hundreds of tons of stone or brick. 

By the late 1890s, the historic confluence of high real estate prices, the safety elevator, and the introduction of the steel skeleton frame set off a national boom in erecting tall buildings. The age of skyscraper building had begun.

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