), from ad
in general for a heap or mound of any kind which might be made of stones,
wood, earth, or, any other substance. It was more particularly applied to a
mound, usually composed of earth, which was raised round a besieged town,
and which was gradually increased in breadth and height, till it equalled or
overtopped the walls. Hence we find the expressions aggere oppidum oppugnare, aggere oppidum cingere;
making of the agger is expressed by the verbs exstruere,
construere, jacere, facere,
&c. Some of these aggeres
were gigantic works, flanked with [p. 1.44]
towers to defend the workmen and soldiers, and
surmounted by parapets, behind which the soldiers could discharge missiles
upon the besieged towns. At the siege of Avaricum, Caesar raised in
twenty-five days an agger 330 feet broad, and 80 feet high. (B.
Agger, from Column of Trajan.
the agger was sometimes made of wood, hurdles, and similar
materials, we read of its being set on fire. (Liv.
; Caes. Gal. 7.24
2.14, 15.) The word agger
was also applied to the earthen wall surrounding a Roman
encampment, composed of the earth dug from the ditch (fossa
), which was usually nine feet broad and seven feet
deep; but if any attack was apprehended, the depth was increased to twelve
feet, and the breadth to thirteen feet. Sharp stakes, &c., were
usually fixed upon the agger, which was then called vallum.
When both words are used (as in Caesar, Caes. Gal. 7.72
, agger ac
), the agger means the mound of earth; and the vallum
the sharp stakes (valli
) which were fixed upon
At Rome, the formidable rampart erected by Servius Tullius to protect the
north-eastern side of Rome was called agger.
extended sevenstadia, or about 1400 yards, from the Porta Collina to the
Porta Esquilina, at the back of the Esquiline hill, where Rome is least
fortified by nature. It was fifty feet broad, and protected by a ditch a
hundred feet wide and thirty feet deep; and the Servian wall was carried
along the top of it. (Cic. de Rep.
; Dionys. A. R. 9.68
Pliny (Plin. Nat. 3.67
) attributes the
erection of this rampart to Tarquinius Superbus, who may have completed the
work of his predecessor. Recent excavations have greatly cleared up the
subject of this agger,
which the older writers
sometimes failed to distinguish from the wall itself. (See Burn,
p. 48 ff., and the map facing p. 49.)