ties of the globe; nor has the city in any age been
exposed to the convulsions of nature which in the climate of Antioch,
Lisbon, or Lima, have crumbled in a few moments the works of ages in
the dust. Fire is the most powerful agent of life and death....

From her situation, Rome is exposed to the danger of frequent
inundations. Without excepting the Tiber, the rivers that descend from
either side of the Apennine have a short and irregular course; a
shallow stream in the summer heats; an impetuous torrent when it is
swelled in the spring or winter by the fall of rain and the melting of
the snows. When the current is repelled from the sea by adverse
winds, when the ordinary bed is inadequate to the weight of waters,
they rise above the banks and overspread without limits or control the
plains and cities of the adjacent country. Soon after the triumph of
the first Punic war, the Tiber was increased by unusual rains; and the
inundation, surpassing all former measure of time and place, destroyed
all the buildings that were situate below the hills of Rome. According
to the variety of ground, the same mischief was produced by different
means; and the edifices were either swept away by the sudden impulse,
or dissolved and undermined by the long continuance of the flood.
Under the reign of Augustus the same calamity was renewed: the lawless
river overturned the palaces and temples on its banks; and after the
labors of the Emperor in cleansing and widening the bed that was
incumbered with ruins, the vigilance of his successors was exercised
by similar dangers and designs. The project of diverting into new
channels the Tiber itself, or some of the dependent streams, was long
opposed by superstition and local interests; nor did the use
compensate the toil and costs of the tardy and imperfect execution.
The servitude of rivers is the noblest and most important victory
which man has obtained over the licentiousness of nature; and if such
were the ravages of the Tiber under a firm and active government, what
could oppose, or who can enumerate, the injuries of the city after the
fall of the Western Empire? A remedy was at length produced by the
evil itself: the accumulation of rubbish and the earth that has been
washed down from the hills is supposed to have elevated the plain of
Rome fourteen or fifteen feet perhaps above the ancient level: and the
modern city is less accessible to the attacks of the river.

II. The crowd of writers