Page:Archaeological Journal, Volume 1.djvu/111



military works of the Saxons were formed by throwing the contents of a ditch inwards as a rampart, upon the ridge of which they appear in some cases to have placed a palisade of timber. The spot chosen was usually the top of a hill, and the figure of the entrenchment depended upon the disposition of the ground. Additional banks and ditches were added upon the less steep sides, and the road winding up from below passed obliquely through the defences.

In more permanent intrenchments a wall was constructed upon the outer face of the mound. The Romans, whose works were defended on this principle, called the ditch, bank, and wall, the fossa, agger, and vallum.

The Romans, who carried heavy baggage, trusted more to the discipline of their sentinels, and cared less for a distant view. Their field works lie in the lower country, and though formed of earth, are set out by the rules of castrametation, and are commonly rectangular, with two or four entrances.

Their permanent stations were constructed upon a greater scale. A rectangular area was enclosed by a thick wall, from fifteen to twenty feet high, strengthened by buttresses, or towers projecting externally, and a ditch. The 'Prætorian' and 'Decuman' gates were in the middle of opposite sides, and the 'Principal' gates were similarly placed in the remaining sides, the roads crossing at right angles in the centre. The direction of the main streets of Chester, Wallingford, and Caerwent, shew the Roman origin of each place. The