The structural definition of the word skyscraper was refined later by architectural historians, based on engineering developments of the 1880s that had enabled construction of tall multi-story buildings.This definition was based on the steel skeleton—as opposed to constructions of load-bearing masonry, which passed their practical limit in 1891 with Chicago's Monadnock Building. The force and power of altitude must be in it, the glory and pride of exaltation must be in it.Note that this criterion fits not only high-rises but some other tall structures, such as towers.
A Florentine law of 1251 decreed that all urban buildings be immediately reduced to less than 26 m.
The medieval Egyptian city of Fustat housed many high-rise residential buildings, which Al-Muqaddasi in the 10th century described as resembling minarets.
One common feature of skyscrapers is having a steel framework that supports curtain walls.
These curtain walls either bear on the framework below or are suspended from the framework above, rather than resting on load-bearing walls of conventional construction.
What is the chief characteristic of the tall office building? It must be every inch a proud and soaring thing, rising in sheer exaltation that from bottom to top it is a unit without a single dissenting line.