天下高楼无极限
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Home Insurance Building
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 …
摩天大楼创建于美国。早在19世纪80年代，两种新技术的发展使建立高楼成为可能。其一是机械升降梯，它的发展意味着人们上高楼时不用再爬楼梯。同样让建高楼成为可能的还有钢结构建筑技术的发展。 许多专家认为伊利诺伊州芝加哥市的家庭保险大楼是世界上的第一座摩天大楼。它建立于1885年，后来又加盖了几层，楼高大概有55米。…