Pons
（
γέφυρα). A bridge. The earliest bridge mentioned in
history is one built at Babylon across the Euphrates. It was of wood, and was constructed in
the reign of Queen Nitocris, about B.C. 606 (
Herod.i. 178-186). In
Greece the earliest bridges were temporary ones
resting on floats like a pontoon, with cables of flax and papyrus tightly strained by
windlasses to support the planking. These bridges were called
σχεδίαι, and were for military purposes only. Such was the high bridge thrown
across the Thracian Bosporus by a Samian Greek named Mandrocles at the order of the Persian
king Darius (
Herod.iv. 83Herod., 85Herod., 87Herod., 88), and such also, though
more carefully built, was that over the Hellespont connecting Sestos and Abydos, built for
Xerxes when he invaded Greece in B.C. 480 (
Herod.vii. 36). It was
not, in fact, until Greece had fallen under Roman influence that permanent bridges were built
over its streams, partly because these were so very narrow, and partly perhaps because of the
feeling that to span a river with a bridge was an insult to the rivergod. Later, however, the
Roman engineers erected massive structures of stone of remarkable size, as that over the
Acheron which was a thousand feet in length (Pliny ,
Pliny H. N. iv. 1), and that which united the island
of Euboea to the mainland.
The Romans, in fact, were great bridge-builders, employing brick
and concrete, or solid stone masonry fastened by iron clamps and lead. Roman bridges were
usually quite narrow in proportion to their length. The central roadway for horses and
vehicles was called
iter. By the side of it ran footpaths, slightly
raised and protected on the outside by a low wall. In the most elaborate bridges, such as the
Pons Aelius at Rome, statues and columns were set at regular intervals along the parapet,
while the main arches were decorated with mouldings. In some cases a tower was built as a
defence at each end of the bridge.
Under the later Roman Empire the following bridges existed in the city of Rome:
1.
The Pons Sublicius, which got its name from the wooden beams
(
sublicae) of which it was built. Until the second century B.C. this
was the only bridge in Rome. It was said to have been built by Ancus Martius, and it
connected the main city with the long walls leading from the right bank of the Tiber to the
fortress on the Ianiculum. No traces of it now exist.
2.
The Pons Aemilius, also called the Pons Lapideus, which was the
first stone bridge built in Rome. It was begun in B.C. 179 and completed about 146. It
spanned the river near the theatre of Marcellus on the site now occupied by the Ponte
Rotto.
3.
The Pons Fabricius, built in B.C. 62 by L. Fabricius, as is
recorded in inscriptions cut across the face of its arches. It unites the Insula Tiberina
with the left bank of the river. During the Middle Ages this bridge was called Pons Iudaeus,
from its proximity to the Jewish quarter (Ghetto).
4.
The Pons Cestius, which unites the Insula Tiberina to the right
side of the river. It was probably built in B.C. 46, and an inscription upon it records its
restoration in A.D. 370.
5.
The Pons Aelius, built in A.D. 135 by the emperor Hadrian to
connect his Mausoleum with the Campus Martius. (See illustration, p. 1018.)
6.
The Pons Aurelius, of uncertain date and probably on the site of
the modern Ponte Sisto.
7.
The Pons Neroniānus or Vaticānus, begun by Caligula and completed by Nero. The foundations of its
piers are still visible in summertime a little below the Pons Aelius.
8.
The Pons Mulvius, now called Ponte Molle, continues the Via
Flaminia across the Tiber. It was built in B.C. 109 by the censor, M. Aemilius Scaurus. On
this bridge Cicero caused the arrest of the ambassadors of the Allobroges at the time of
Catiline's conspiracy, and in A.D. 312 it was the scene of the rout of Maxentius by
Constantine. Under the Empire the Pons Mulvius was a favourite pleasure-resort for the lower
classes of Rome (
Tac. Ann. xiii. 47). Bridges
in general were thronged by beggars who importuned the passersby. See
Mendicus.
Among the best-preserved stone bridges built by the Romans and still preserved are
the bridge at Rimini (Ariminum), shown in the accompanying illustration; the combined
aqueduct and bridge near Nîmes, in France (see illustration under
Nemausus); the single-arched bridge near Brioude
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Roman Bridge at Rimini.
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over the Allier; and (in a less complete condition) the bridges at Narni near Rome
and at Alcantara across the river Tagus in Spain, this last being 670 feet in length.
The Romans showed great skill in constructing temporary bridges. The most famous of these
was the bridge built by Caesar over the Rhine and described by him in a passage (
B.
G. iv. 17) whose translation and explanation are the terror of school-boys, and of
some schoolmasters as well. This bridge was finished within ten days, and may be described as
follows:
It was supported on a series of double piles, formed of two baulks of timber, each eighteen
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Plan of Caesar's Bridge over the Rhine. (a) Rough joists. (b) Wattle-work. (c) Roadway of earth.
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inches square (in section), pointed at one end, and driven into the bed of the
river by machines called
fistucae; they were set in a sloping direction,
so as to resist the force of the current. A corresponding parallel row of piles was driven in
at a distance of forty feet, thus forming a very wide roadway for the Roman army. The
cross-pieces were two feet thick, and were supported by cross struts
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Transverse Section of Caesar's Bridge.
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so as to diminish the bearing. A little higher up the stream a third row of piles
was fixed to support “fenders,” to secure the main structure from injury
in case the enemy set heavy trees to float down the river and strike against the supports of
the bridge.
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Longitudinal Section of Caesar's Bridge.
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Other temporary bridges were supported by floating casks (
dolia,
cupae) or on boats (Veget. iii. 7; Florus, iii. 5). The accompanying illustration shows
one of the latter bridges.
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Bridge Supported on Boats. (Column of Trajan.)
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See
Mayerhöfer, Die Brücken im alten Rom
(1884); Zippel in the
Jahrbücher für klass.
Philologie, pp. 481 foll.
(1886); and Middleton,
Remains of
Ancient Rome, ii. 362-371
(1892).
The word
pons also denotes any sort of wooden gangway, such as the
pons suffragiorum through which the voters passed at the Comitia (see
illustration under
Ovile); and was applied to the
gangplank (
ἀποβάθρα) of a ship whence, by a species of
metonymy, the deck itself is called
ponte in modern Italian and
pont in French.
