domesticated in the
Capitol; and these required more sumptuous fanes than those with which
the native deities had been contented. The brown tufa of the Tarpeian
Rock sufficed for the rude sanctuary of Vesta, the primitive
hearth-stone of ancient Rome; but in the reconstruction of the
sumptuous temple of Jupiter Capitolinus, which marked the grandest
period of Roman history, the most precious stones of Asia and Africa
were employed. Statues were imported wholesale from Greece to adorn
temples and theatres, constructed after the models of Greek
architecture, with pillars, friezes, and floors of precious Pentelic
and Sicilian marble. During the last century of the Republic marble
became a common building-stone. The tomb of Caecilia Metella, and the
temples of Ceres, Juno Sospita, and Castor and Pollux, indicate the
introduction of this precious and beautiful material. But it was
reserved for the period of the Empire to complete the architectural
glories of the city. Travertine, usually called _Lapis Tiburtinus_, a
straw-coloured volcanic limestone excavated in the plain below Tivoli,
which has the useful property of hardening on exposure, was now used
as the principal building-stone instead of the former lavas and tufas;
and the Colosseum, entirely constructed of travertine, which was
treated in the middle ages as a quarry, out of which were built many
of the palaces and churches of Rome, attests to this day the beauty
and durability of this material. Quarries of crystalline marbles,
admirably adapted for the purposes of the sculptor and architect, were
opened in the range of the Apennines overlooking the beautiful Bay of
Spezia, in the vicinity of Carrara, Massa, and Seravezza, and largely
worked in the time of Augustus. This emperor could boast that he had
found Rome of brick, and left it of marble. The marbles of each new
territory annexed to the Empire were brought at enormous expense into
the Imperial City. A quay, to which reference has already been made,
was constructed at the broadest part of the Tiber, where the vessels
that transported marbles from Africa, and from the most distant parts
of Eastern Europe and Western Asia, landed their cargoes. Here
numerous blocks of marble were lately found, one of which was
identified as that sent to Nero from a quarry in Carinthia; and
another, a column of even more colossal dimensions, weighing about
thirty-four tons of valuable African marble, was meant to serve as a
memori