SECT. I.]

Introduction.

15
hedge, or wall, or protection of some kind ; these outer fortifications
were called the moenia, and also the finis or end of the fortifications.
Each fortification usually consisted of three parts :—
a. The arx, or citadel, or keep, of comparatively small dimen-
sions, and more strongly fortified than the rest, generally with a triple
line of defence.
b. The dwelling-place, strongly fortified, though not quite so much
so as the arx, generally with a double line of defence, and of larger
extent.
c. The pasture-ground, usually of much greater extent than the
other two, but slightly fortified with a single line of defence only on
the edge of the cliff, for this is usually placed on the top of a hill
also when practicable.
d. The divisions between these parts are frequently made by the
hand of man. If the place is on the end of a promontory, ditches
or valleys are cut right through from one cliff to the other, and thus
insulate each of these parts.
Any neighbouring small hill or vantage-ground of any kind is also
taken possession of and fortified as an outwork, to prevent the enemy
taking advantage of it, and these are called detached fortse.
There were also forts to protect weak points, projecting at inter-
vals from the line of the wall; these are connected with the wall by
one end of the fort only, three sides of the parallelogram of which
each consists standing clear, and the line of the foss following the
projection. In the time of Romulus we had the simple fortress, but
by the time of the later kings, these and other small detached forts
had been placed just outside the gates, to protect them.
The general principles already described are applied on an
enormous scale in the Etruscan city of Veii, within twenty miles
of Rome, and the great rival of the ancient Romans until it was
conquered by Camillus, and the population incorporated with the
Romans and transferred to Rome. On one side, the foss or trench
is cut through the solid rock to the depth of thirty feet, like the dry

e The Romans in this country have
left us a large number of primitive forti-
fications, which help us to understand
those of Rome. There is a fine series
of them on the tops of all the hills
from Bristol to Weymouth. Similar
fortifications were made in the fifth and
sixth centuries to defend the western
counties against the Saxon invaders.
In these and in many similar instances
we find a scarped cliff, and an outer

ditch, making a pomcerium between
them. We also find that each fortress
consisted of two parts : a small one
more strongly fortified, intended for hu-
man habitation, equivalent to the inner
ward or body of a medieval castle ; and
a large one, equivalent to the outer
bailey, less strongly fortified, and evi-
dently intended for cattle only. There
is frequently also a third part, of small
dimensions, for the arx or citadel.