The envoys then betook themselves to their own army. And when Vittigis enquired of them what manner of man Belisarius was and how his purpose stood with regard to the question of withdrawing from Rome, they replied that the Goths were hoping for vain things if they supposed that they would frighten Belisarius in any way whatsoever. And when Vittigis heard this, he began in great earnest to plan an assault upon the wall, and the preparations he made for the attempt upon the fortifications were as follows. He constructed wooden towers equal in height to the enemy's wall, and he discovered its true measure by making many calculations based upon the courses of stone. And wheels were attached to the floor of these towers under each corner, which were intended, as they turned, to move the towers to any point the attacking army might wish at a given time, and the towers were drawn by oxen yoked together. After this he made ready a great number of ladders, that would reach as far as the parapet, and four engines which are called rams. Now this engine is of the following sort. Four upright wooden beams, equal in length, are set up opposite one another. To these beams they fit eight horizontal timbers, four above and an equal number at the base, thus binding them together. After they have thus made the frame of a four-sided building, they surround it on all sides, not with walls of wood or stone, but with a covering of hides, in order that the engine may be light for those who draw it and that those within may still be in the least possible danger of being shot by their opponents. And on the inside they hang another horizontal beam from the top by means of chains which swing free, and they keep it at about the middle of the interior. They then sharpen the end of this beam and cover it with a large iron head, precisely as they cover the round point of a missile, or they sometimes make the iron head square like an anvil. And the whole structure is raised upon four wheels, one being attached to each upright beam, and men to the number of no fewer than fifty to each ram move it from the inside. Then when they apply it to the wall, they draw back the beam which I have just mentioned by turning a certain mechanism, and then they let it swing forward with great force against the wall. And this beam by frequent blows is able quite easily to batter down and tear open a wall wherever it strikes, and it is for this reason that the engine has the name it bears, because the striking end of the beam, projecting as it does, is accustomed to butt against whatever it may encounter, precisely as do the males among sheep. Such, then, are the rams used by the assailants of a wall. And the Goths were holding in readiness an exceedingly great number of bundles of faggots, which they had made of pieces of wood and reeds, in order that by throwing them into the moat they might make the ground level, and that their engines might not be prevented from crossing it. Now after the Goths had made their preparations in this manner, they were eager to make an assault upon the wall.But Belisarius placed upon the towers engines which they call "ballistae."[103] Now these engines have the form of a bow, but on the under side of them a grooved wooden shaft projects; this shaft is so fitted to the bow that it is free to move, and rests upon a straight iron bed. So when men wish to shoot at the enemy with this, they make the parts of the bow which form the ends bend toward one another by means of a short rope fastened to them, and they place in the grooved shaft the arrow, which is about one half the length of the ordinary missiles which they shoot from bows, but about four times as wide. However, it does not have feathers of the usual sort attached to it, but by inserting thin pieces of wood in place of feathers, they give it in all respects the form of an arrow, making the point which they put on very large and in keeping with its thickness. And the men who stand on either side wind it up tight by means of certain appliances, and then the grooved shaft shoots forward and stops, but the missile is discharged from the shaft,[104] and with such force that it attains the distance of not less than two bow-shots, and that, when it hits a tree or a rock, it pierces it easily. Such is the engine which bears this name, being so called because it shoots with very great force.[105] And they fixed other engines along the parapet of the wall adapted for throwing stones. Now these resemble slings and are called "wild asses."[106] And outside the gates they placed "wolves,"[107] which they make in the following manner. They set up two timbers which reach from the ground to the battlements; then they fit together beams which have been mortised to one another, placing some upright and others crosswise, so that the spaces between the intersections appear as a succession of holes. And from every joint there projects a kind of beak, which resembles very closely a thick goad. Then they fasten the cross-beams to the two upright timbers, beginning at the top and letting them extend half way down, and then lean the timbers back against the gates. And whenever the enemy come up near them, those above lay hold of the ends of the timbers and push, and these, falling suddenly upon the assailants, easily kill with the projecting beaks as many as they may catch. So Belisarius was thus engaged.