The architecture of Ancient Rome is probably one of the most significant testimonies of Roman civilization. It is characterized by having adopted the external language of classical Greek architecture, to which he added several original innovations. The two styles are often considered a body, which is known as classical architecture. Roman architecture flourished in the Roman Republic and even more so under the Empire, when the great majority of the surviving buildings were built. He used new materials, particularly Roman concrete, and technologies such as the semicircular arch, the arcade, the vault and the dome to make buildings that were normally strong and well designed.
Roman architecture covers the period between the establishment of the Roman Republic in the year 509 a. C. until approximately the IV century d. C., after which the late ancient or Byzantine architecture is present. Almost no substantial example survives from before the year 100 a. C., and most of the most important survivals come from the later Empire, after approximately 100 d. C. The Roman architectural style continued influencing construction for many centuries, and the style used in Western Europe from the year 1000 is called Romanesque architecture in reference to the dependence on basic Roman forms.
Canals and railroads were important to American development because both railroads and canals crisscrossed the states, providing transportation infrastructure that fueled the growth of American commerce.
The past war crash in america occured after WW1 as the result of high inventories of manufactored goods with no local buyers and a drop-off in exports, and falling prices for farm produce
