The wealth poured into Rome by the conquest of Carthage, of Greece, and
the East, and the considerable revenue derived from the permanent
taxation of the provinces, enabled the Romans to carry out a great
system of public works. Throughout Italy splendid military roads which
remain to this day were built, the provinces were traversed by imperial
highways, and fine stone bridges were thrown across the Tiber. In Rome
splendid public buildings were erected, the city was sewered, the
streets were paved (174 B. C.), two new aqueducts (the Marcian, built in
144 B. C., at a cost of ten million dollars) were constructed; and it
may be noted that the Consul P. Scipio Nasica, in 159 B. C., set up in
Rome a public clepsydra, or water clock, the citizens having for six
centuries gone on without any accurate means of knowing the time by
night as well as day.