In "The Fall of Rome: And the End of Civilization," Bryan Ward-Perkins reports that the pollutants which are the byproducts of industrial activity did not reach Roman levels in Britain until the 18th century! I am not naive enough to be such a partisan of the “ancients” as to suggest that Europe did not reach Roman levels of civilization in the generality until the 1700s. But, up until the Industrial Revolution occurred in Britain there were aspects of European civilization which had not yet climbed back up to the Roman scale of grandeur or virtuosity. For example, it seems that it was only in 1800 that London attained the size of the city of ancient Classical Rome (which had fallen in its nadir in the 7th century to a population of 50,000).
- Per Razib (links omitted, punctuation added in lieu of link emphasis).