PISCI´NA
PISCI´NA (
κολυμβήθρα,
δεξαμενὴ) is properly a fish-pond, either
of salt water or of fresh; see the passages in Forcellini and the
Dictionaries. It denotes also any kind of reservoir, especially those
connected with the aqueducts and the baths (
AQUAEDUCTUS p. 149
a;
BALNEAE
[p. 2.430]p. 275
b, note).
Conversely, the Greek
κολυμβήθρα was by no
means confined to its original meaning of a swimming-bath, but included the
various senses of
piscina.
Reservoirs were made, as in modern times, by damming up the lower end of a
valley. One of the largest and finest was constructed at Agrigentum and is
described by Diodorus (
11.25), though in his
time it had ceased to exist; it was seven stadia in circumference, twenty
cubits deep, an ornamental sheet of water abounding with fish and swans: he
calls it
κολυμβήθρα, a good example of this
use of the word. The hollow of the hill which this reservoir occupied is
still plainly to be distinguished, especially from the Temple of Castor and
Pollux (cf.
EMISSARIUM).
The Romans, with their unbounded command of water-tight cement, were
particularly successful in the excavation of underground reservoirs; and
having to deal with the highly calcareous water from the Apennines, they had
learnt how to get rid of the sedimentary deposits. In the so-called
Sette Sale on the Esquiline, a still existing reservoir
attached at first to the Golden House of Nero, afterwards to the Baths of
Titus, the water was made to flow through no less than eighteen
subdivisions, in as devious a course as possible, so that any sediment it
contained might be deposited on the way (Middleton,
Anc. Rome
in 1885, p. 352).
An unrivalled work of this description is the
Piscina
Msirabile as it is now called, on the road between Baiae and the
promontory of Misenum, and still in perfect preservation. This reservoir is
excavated out of the tufa rocks on the seacoast, and was used for watering
the fleet in days when the naval head-quarters were at Misenum; it is not
mentioned by Pliny or any other Latin writer, but it is referred by
Winckelmann with great probability to the time of Augustus, and to Agrippa
as its constructor. It is 223 feet long and 83 broad, with a vaulted roof of
massive masonry, supported by 48 large cruciform pilasters, arranged in
regular lines of 12 each, and forming 5 distinct galleries or conpartments.
It is entered at the two extremities by stairs of 40 steps each, one of
which has been repaired and made accessible. In the middle of the piscina is
a depression or sink, extending nearly from wall to wall, for collecting the
sediment from the water. The roof is perforated by square openings, which
probably served for ventilating the interior. The walls and pilasters are
covered with a calcareous deposit as high as the spring of the arches. It
was supplied by the Julian aqueduct from Lake Serino in the Apennines, whose
waters have within the last few years been re-introduced into Naples; the
traces of the aqueduct entering the piscina may be seen near the entrance.
(Murray's
Handbook of Southern Italy, ed. 1883, p. 330;
Handbook of Sicily, s. v.
Agrigentum; personal observation.)
[
W.W]
