What I have just said suggests that I should, as briefly as my modest ability permits, give a concise description of engines of this kind, for the benefit of those who are unacquainted with them; and I shall first explain the form of the ballista.See illustrations between pp. 328 and 329. These give a general idea of the scorpion and the ram, although they do not contain all the features of Ammianus’ description.

Between two posts along, strong iron baris fastened, and projects like a great ruler; from its smooth, rounded surface, which in the middle is highly polished, a squared staff extends to a considerable distance, hollowed out along its length with a narrow groove, and bound there with a great number of twisted cords. To this two wooden rollers are very firmly attached, and near one of them stands the gunner who aims the shot. He carefully places in the groove of the projecting iron bar a wooden arrow, tipped with a great iron point. When this is done, strong young men on both sides quickly turn the rollers and the cords.

When its point has reached the outermost ropes, the arrow, driven by the power within, flies from the ballista out of sight,Its action is like that of a huge crossbow. The arrow is drawn back by a cord fastened to the ropes on the rollers. When the catch is released, these ropes drive out the arrow. sometimes emitting sparks because of the excessive heat. And it often happens that before the weapon is seen, the pain of a mortal wound makes it felt.

The scorpion, which is now-a-days called the wild ass, has the following form. Two posts of oak or holm-oak are hewn out and slightly bent, so that they seem to stand forth like humps. These are fastened together like a sawing-machine and bored through on both sides with fairly large holes. Between them, through the holes, strong ropes are bound, holding the machine together, so that it may not fly apart.

From the middle of these ropes a wooden arm rises obliquely, pointed upward like the pole of a chariot,I.e. when the horses are not harnessed to it. and is twined around with cords in such a way that it can be raised higher or depressed. To the top of this arm, iron hooks are fastened, from which hangs a sling of hemp or iron. In front of the arm is placed a great cushion of hair-cloth stuffed with fine chaff, bound on with strong cords, and placed on a heap of turf or a pile of sundried bricks; for a heavy machine of this kind, if placed upon a stone wall, shatters everything beneath it by its violent concussion, rather than by its weight.

Then, when there is a battle, a round stone is placed in the sling and four young men on each side turn back the bar with which the ropes are connected and bend the pole almost flat. Then finally the gunner, standing above, strikes out the pole-bolt, which holds the fastenings of the whole work, with a strong hammer, thereupon the pole is set free, and flying forward with a swift stroke, and meeting the soft hair-cloth, hurls the stone, which will crush whatever it hits.

And the machine is called tormentum as all the released tension is caused by twisting (torquetur); and scorpion, because it has an upraised sting; modern times have given it the new name onager, because when wild asses are pursued by hunters, by kicking they hurl back stones to a distance, either crushing the breasts of their pursuers, or breaking the bones of their skulls and shattering them.

Now we shall come to the ram. A tall fir or mountain ash is selected, to the end of which is fastened a long, hard iron; this has the appearance of a projecting ram’s head, and it is this shape which has given the machine its name. This is suspended between ironbound beams running across on both sides, so that it hangs from a third beam like the pan of a balance. Then a number of men, as great as the length of the pole permits, draw it back and then shove it forward again with powerful blows, just as a ram charges and retreats, to break everything in its way. As this is renewed with the force of a repeated stroke of lightning,The ancients believed that a stroke of lightning returned to the sky, doing damage as it came and as it went. Cf. Lucan, i, 156. buildings are cracked and shattered as the structure of their walls is destroyed.

If this kind of engine is worked with full vigour, the strongest cities, after their walls have been stripped of defenders, are laid open, and the siege is thus brought to an end.

In place of these devices of rams, which, because they are now so frequent, are in less esteem, a machine is made, well known to the historians, which we Greeks call helepolis.City-taker. The descriptions of Diod. xx. 48 and 91, and Athen. v. p. 206 d, are of a more powerful machine, including lofty towers. It was through the constant employment of this engine that Demetrius, the son of King Antigonus, after taking Rhodes and other cities gained the name of Poliorcetes.Besieger of cities.

It is built in the following manner: a huge mantletOr tortoise-shed. is constructed of strong planks of great length fastened together with iron nails, and covered with ox-hides and hurdles of green twigs; and over these is spread mud, in order to protect it from fire and falling missiles.

On its front side are set very sharp,Cf. falces praeacutae, Caes., iii. 14, 5, and , vi. (1910), pp. 133 f. three-pronged spear-points, of the form which our painters and sculptors give to thunderbolts, made heavy with iron weights, so that whatever it attacks it shatters with the projecting points.