天下高樓無極限
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Chicago
Illinois
Skyscrapers were invented in the United States. As early as the 1880s, 2 new technical developments made these taller buildings possible. One development was the mechanical elevator. It meant that people would not have to climb many steps to reach the upper floors of tall buildings. The development …
摩天大樓創(chuàng)建于美國。早在19世紀80年代，兩種新技術的發(fā)展使建立高樓成為可能。其一是機械升降梯，它的發(fā)展意味著人們上高樓時不用再爬樓梯。同樣讓建高樓成為可能的還有鋼結(jié)構建筑技術的發(fā)展。 許多專家認為伊利諾伊州芝加哥市的家庭保險大樓是世界上的第一座摩天大樓。它建立于1885年，后來又加蓋了幾層，樓高大概有55米。…