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

[131] NOW the king of Babylon was very intent and earnest upon the siege of Jerusalem; and he erected towers upon great banks of earth, and from them repelled those that stood upon the walls; he also made a great number of such banks round about the whole city, whose height was equal to those walls. However, those that were within bore the siege with courage and alacrity, for they were not discouraged, either by the famine, or by the pestilential distemper, but were of cheerful minds in the prosecution of the war, although those miseries within oppressed them also, and they did not suffer themselves to be terrified, either by the contrivances of the enemy, or by their engines of war, but contrived still different engines to oppose all the other withal, till indeed there seemed to be an entire struggle between the Babylonians and the people of Jerusalem, which had the greater sagacity and skill; the former party supposing they should be thereby too hard for the other, for the destruction of the city; the latter placing their hopes of deliverance in nothing else but in persevering in such inventions in opposition to the other, as might demonstrate the enemy's engines were useless to them. And this siege they endured for eighteen months, until they were destroyed by the famine, and by the darts which the enemy threw at them from the towers.