This article traces the evolution of the powered passenger elevator from its initial development in the mid-19th century to the installation of the three separate elevator systems in the Eiffel Tower in 1889. The design of the Tower’s elevators involved problems of capacity, length of rise, and safety far greater than any previously encountered in the field; and the equipment that resulted was the first capable of meeting the conditions of vertical transportation found in the just emerging skyscraper.
The Author: Robert M. Vogel is associate curator of mechanical and civil engineering, United States National Museum, Smithsonian Institution.
The 1,000-foot tower that formed the focal point and central feature of the Universal Exposition of 1889 at Paris has become one of the best known of man’s works. It was among the most outstanding technological achievements of an age which was itself remarkable for such achievements.
Second to the interest shown in the tower’s structural aspects was the interest in its mechanical organs. Of these, the most exceptional were the three separate elevator systems by which the upper levels were made accessible to the Exposition visitors. The design of these systems involved problems far greater than had been encountered in previous elevator work anywhere in the world. The basis of these difficulties was the amplification of the two conditions that were the normal determinants in elevator design—passenger capacity and height of rise. In addition, there was the problem, totally new, of fitting elevator shafts to the curvature of the Tower’s legs. The study of the various solutions to these problems presents a concise view of the capabilities of the elevator art just prior to the beginning of the most recent phase of its development, marked by the entry of electricity into the field.
The great confidence of the Tower’s builder in his own engineering ability can be fully appreciated, however, only when notice is taken of one exceptional way in which the project differed from works of earlier periods as well as from contemporary ones. In almost every case, these other works had evolved, in a natural and progressive way, from a fundamental concept firmly based upon precedent. This was true of such notable structures of the time as the Brooklyn Bridge and, to a lesser extent, the Forth Bridge. For the design of his tower, there was virtually no experience in structural history from which Eiffel could draw other than a series of high piers that his own firm had designed earlier for railway bridges. It was these designs that led Eiffel to consider the practicality of iron structures of extreme height.
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