Flavius Josephus, The Wars of the Jews
William Whiston, A.M., Ed.

[161] Vespasian, therefore, in order to try how he might overcome the natural strength of the place, as well as the bold defense of the Jews, made a resolution to prosecute the siege with vigor. To that end he called the commanders that were under him to a council of war, and consulted with them which way the assault might be managed to the best advantage. And when the resolution was there taken to raise a bank against that part of the wall which was practicable, he sent his whole army abroad to get the materials together. So when they had cut down all the trees on the mountains that adjoined to the city, and had gotten together a vast heap of stones, besides the wood they had cut down, some of them brought hurdles, in order to avoid the effects of the darts that were shot from above them. These hurdles they spread over their banks, under cover whereof they formed their bank, and so were little or nothing hurt by the darts that were thrown upon them from the wall, while others pulled the neighboring hillocks to pieces, and perpetually brought earth to them; so that while they were busy three sorts of ways, nobody was idle. However, the Jews cast great stones from the walls upon the hurdles which protected the men, with all sorts of darts also; and the noise of what could not reach them was yet so terrible, that it was some impediment to the workmen.