VALLUM
VALLUM a term applied either to the whole or a portion of the
fortifications of a Roman camp. It is derived from
callus (a stake), and properly means the palisade which ran along
the outer edge of the top of the agger, but it very frequently includes the
agger also. The vallum, in the latter sense, together with the
fossa or ditch which surrounded the camp outside of
the vallum, formed a complete fortification [
AGGER], and accordingly the word
vallum is almost always found in connexion with
fossa.
The
valli (
χάρακες) or
sudes (Caes.
Bell. Gall. 5.40, 6; Veg. 1.24, 3.8), of which the
vallum, in the former and more limited sense, was composed, are described by
Polybius (
18.18,
5
ff., ed. Hultsch = 18.1, ed. vulg.: see Mr. Strachan-Davidson's notes on
this difficult passage, pp. 416-17) and Livy (
33.5), who make a comparison between the vallum of the Greeks and
that of the Romans, very much to the advantage of the latter. Both used for
valli young trees or arms of larger trees with the side branches on them;
but the valli of the Greeks were much larger and had more branches than
those of the Romans, which had either two or three, or at the most four
branches, and these generally on the same side. From their similarity to the
antlers of a stag (
Sil. Ital. 10.414),
they were sometimes called
cervi (Varro,
L. L. 5.117, Miller; Caes.
Bell. Gall.
7.72, 4;
Tib. 4.1,
84:
cf.
Liv. 44.11,
4),
or
cervoli (Frontin.
Strateg. 1.5, 2;
Hygin.
de Mun. Castr. § 51). The Greeks placed their
valli in the agger at considerable intervals, the spaces between them being
filled up by the branches; the Romans fixed theirs close together, and made
the branches interlace, and sharpened their points carefully. Hence the
Greek vallus could easily be taken hold of by its large branches and pulled
from its place, and when it was removed a large opening was left in the
vallum. The Roman vallus, on the contrary, presented no convenient handle,
required very great force to pull it down, and even if removed left a very
small opening, as the stake itself was so small. The Greek valli were cut on
the spot; the Romans prepared theirs beforehand, and each soldier carried
three or four of them when on a march (Polyb.
l.c.;
Verg. G. 3.346,
347;
Cic. Tusc.
2.16, 37; Liv.
l.c. and
Epit.
lvii.). They were made of any strong wood, but oak was preferred.
The word
vallus is sometimes used as equivalent
to vallum (Caesar,
Caes. Civ. 3.63).
A fortification like the Roman vallum was used by the Greeks at a very early
period (
Hom. Il. 9.349,
350).
Varro's etymology of the word (viz. “vel quod ea varicare [stride over
it] nemo potest vel quod singula ibi extrema bacilla furcillata habent
figuram litterae V:”
L. L. 5.117, ed. Müller) is not worth much. The real
derivation is probably from the root
var (
val), “to protect,” whence
vereri,
ἧλος; cf. Vaniçek, pp. 900,
901.
In the operations of a siege, when the place could not be taken by storm, and
it became necessary to establish a blockade, this was done by drawing
defences similar to those of a camp round the town, which was then said to
be
circumvallatum. Such a circumvallation,
besides cutting off all communication between the town and the surrounding
country, formed a defence against the sallies of the besieged. There was
often a double line of fortifications, the inner
[p. 2.919]against the town, and the outer against any force that might attempt to
raise the siege. In this case the army was encamped between the two lines of
works.
This kind of circumvallation, which the Greeks called
ἀποτειχισμὸς and
περιτειχισμός, was employed by the Peloponnesians in the siege
of Plataeae (
Thuc. 2.78,
3.20-
23). Their lines consisted of
two walls (apparently of turf) at the distance of 16 feet, which surrounded
the city in the form of a circle. Between the walls were the huts of the
besiegers. The walls had battlements (
ἐπάλξεις), and at every tenth battlement was a tower, filling
up by its depth the whole space between the walls. There was a passage for
the besiegers through the middle of each tower. On the outside of each wall
was a ditch (
τάφρος). This description
would almost exactly answer for the Roman mode of circum-vallation, of which
some of the best examples are that of Carthage by Scipio (Appian,
Punic. 119, &c.), that of Numantia by Scipio
(Appian,
Hispan. 90), and that of Alesia by Caesar
(
Bell. Gall. 7.72, 73). The towers in such lines were
similar to those used in attacking fortified places, but not so high, and of
course not moveable. [
TURRIS]
(Lipsius,
de Milit. Rom. 5.5, in
Oper. iii.
pp. 156, 157; Poliorc. 2.1, in
Oper. 3.283; Marquardt,
Röm. Staatsverwaltung, ii.2
419; and the art.
CASTRA in Vol.
I. of this Dictionary.)
[
P.S] [
L.C.P]
