Turning their thoughts wholly to arms, the Romans always conducted their military enterprises in the most advantageous way, both as to cost and every other circumstance of war.  For which reason they avoided attempting towns by siege, judging the expense and inconvenience of this method of carrying on war greatly to outweigh any advantage to be gained by it.  Accordingly, they thought it better and more for their interest to reduce towns in any other way than this; and in all those years during which they were constantly engaged in wars we find very few instances of their proceeding by siege.

For the capture of towns, therefore, they trusted either to assault or to surrender.  Assaults were effected either by open force, or by force and stratagem combined.  When a town was assailed by open force, the walls were stormed without being breached, and the assailants were said “aggredi urbem corona,” because they encircled the city with their entire strength and kept up an attack on all sides.  In this way they often succeeded in carrying towns, and even great towns, at a first onset, as when Scipio took new Carthage in Spain.  But when they failed to carry a town by storm, they set themselves to breach the walls with battering rams and other warlike engines; or they dug mines so as to obtain an entrance within the walls, this being the method followed in taking Veii; or else, to be on a level with the defenders, they erected towers of timber or threw up mounds of earth against the outside of the walls so as to reach the top.

Of these methods of attack, the first, wherein the city was entirely surrounded, exposed the defenders to more sudden perils and left them more doubtful remedies.  For while it was necessary for them to have a sufficient force at all points, it might happen that the forces at their disposal were not numerous enough to be everywhere at once, or to relieve one another.  Or if their numbers were sufficient, they might not all be equally resolute in standing their ground, and their failure at any one point involved a general defeat.  Consequently, as I have said, this method of attack was often successful.  But when it did not succeed at the first, it was rarely renewed, being a method dangerous to the attacking army, which having to secure itself along an extended line, was left everywhere too weak to resist a sally made from the town; nay, of itself, was apt to fall into confusion and disorder.  This method of attack, therefore, could be attempted once only and by way of surprise.

Against breaches in the walls the defence was, as at the present day, to throw up new works; while mines were met by counter-mines, in which the enemy were either withstood at the point of the sword, or baffled by some other warlike contrivance; as by filling casks with feathers, which, being set on fire and placed in the mine, choked out the assailants by their smoke and stench.  Where towers were employed for the attack, the defenders sought to destroy them with fire; and where mounds of earth were thrown up against the walls, they would dig holes at the base of the wall against which the mound rested, and carry off the earth which the enemy were heaping up; which, being removed from within as fast as it was thrown up from without, the mound made no progress.