35).

A straight wall, about fifty feet in height, carried along the cliffs on the side next the river; but the walls looking towards the plain rose to eighty feet, and bristled with bastion-like projections (A.B.) jutting out for a distance of fifty feet from the curtain wall, measuring thirty feet thick at the base and thirteen feet at the top, and irregularly spaced, according to the requirements of the defence.

These spurs, which are not battlemented, served in place of towers.

They added to the strength of the walls, protected the walk round the top, and enabled the besieged to direct a flank attack against the enemy if any attempt were made upon the wall of circuit.

The intervals between these spurs are accurately calculated as to distance, in order that the archers should be able to sweep the intervening ground with their arrows.