<Li> <P> 15 March 1889: Construction of the cupola . </P> </Li> <P> 15 March 1889: Construction of the cupola . </P> <P> Equipping the tower with adequate and safe passenger lifts was a major concern of the government commission overseeing the Exposition . Although some visitors could be expected to climb to the first level, or even the second, lifts clearly had to be the main means of ascent . </P> <P> Constructing lifts to reach the first level was relatively straightforward: the legs were wide enough at the bottom and so nearly straight that they could contain a straight track, and a contract was given to the French company Roux, Combaluzier & Lepape for two lifts to be fitted in the east and west legs . Roux, Combaluzier & Lepape used a pair of endless chains with rigid, articulated links to which the car was attached . Lead weights on some links of the upper or return sections of the chains counterbalanced most of the car's weight . The car was pushed up from below, not pulled up from above: to prevent the chain buckling, it was enclosed in a conduit . At the bottom of the run, the chains passed around 3.9 m (12 ft 10 in) diameter sprockets . Smaller sprockets at the top guided the chains . </P>

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