Note 254 — Chapter V · WAR AGAINST THE BELGÆ. (Year of Rome 697.) (Book II. of the “Commentaries.”)

The terrace (agger) was an embankment, made of any materials, for the purpose of establishing either platforms to command the ramparts of a besieged town, or viaducts to conduct the towers and machines against the walls, when the approaches to the place presented slopes which were too difficult to climb. These terraces were used also sometimes to fill up the fosse. The agger was most commonly made of trunks of trees, crossed and heaped up like the timber in a funeral pile.—(Thucydides, Siege of Platæa.—Lucan, Pharsalia.—Vitruvius, book XI., Trajan Column.)