Parker, John Henry: The archaeology of Rome (1,text): I. The primitive fortifications (Oxford [u.a.], 1874)

CHAPTER III.

THE DIFFERENT MODES OF CONSTRUCTION
Employed in Ancient Roman Buildings51, and the Periods
WHEN EACH WAS FlRST INTRODUCED.
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The building-materials employed in Rome—besides marble for
ornament—are stone, clay for bricks, sand, lime.
The varieties of stoneb are :—-
I. Tufa, a volcanic sandstone, generally soft and of a light
yellow, almost white in summer when it is dry0, or some varieties
light red, called by Vitruvius, lapis ruber. The tophus of Vitru-
vius is not the same as the tufa of Rome, but corresponds to the
pumex (VI.) Tufa is called by Virgild and Pliny0 tofts.
The ancient quarries of this are in the Coelian, Aventine, and
Capitoline hills, the modern ones in the Campagnaf. The walls of
Romulus are entirely of this material, and were probably built from
quarries s in the Palatine Hill itselfh, or cut out of the trenches of
the original fortifications. The arches and vaults of the Cloaca
Maxima and of the Mamertine Prison are of tufa.
II. Lapis Albanus, now called peperino, also a volcanic sand-
stone, but hard and rough, the surface covered with knobs of flint,
resembling pepper-corns, hence the name. There are ancient quar-
ries at Albano, near the gate of the town; another near Alba-Longa,
on Monte Cavo. The one at Marino, still in use, is also ancient;
the colour is gray with a tinge of green.

a Tn this Chapter I have been much
indebted to an essay on the subject by
the Cavaliere C. L. Visconti, written for
the British Archaeological Society of
Rome.
b See Vitruvius de Architectura, lib.
ii. c. 7.
c When tufa is wet and exposed to
the weather it is often of quite a dark
colour, looking at a distance almost
black ; it is a very porous stone, and
absorbs the moisture.
d Virgilii Georgic., lib. vii. v. 214.
e Plinii Nat. Hist., lib. xvii. s. 4.
1 See Brocchi—Suola fisico di Roma,
for a description of the quarries of tufa
on the hills of Rome.
There are also very large ancient
quarries of tufa on the bank of the river
Anio, near the sources of the Aqua

Appia, on the edge of the meadows of
Lucullus, and another series nearer to
Rome called the Caves of Cervaro. It
is supposed that the stones for the
great Wall of Servius Tullius were
brought from these quarries, and were
floated down the Anio on rafts.
Tufa varies very much in hardness
and other qualities, as well as in colour.
The different layers or beds of it in
Rome and in the Campagna vary very
much in thickness also, but the beds
are generally about ten or twelve feet
thick, alternately hard and soft.
h Some of the latomia, lautumia, or
quarries of the Palatine, are visible in
the excavations made by the Emperor
of the French, near the foundations of
the temple said to be that of Jupiter
Stator.

B