144

THE DECLINE AND FALL

CHAP.

XVIII.

low tile town, and the waters were confined onevery side by solid mounds of earth. On thisartificial lake, a fleet of armed vessels, filled withsoldiers, and with engines which dischargedstones of five hundred pounds weight, advancedin order of battle, and engaged, almost upon alevel, the troops which defended the ramparts.The irresistible force of the waters was alter-nately fatal to the contending parties, till atlength a portion of the walls, unable to sustainthe accumulated pressure, gave way at once,and exposed an ample breach of one hundredand fifty feet. The Persians were instantlydriven to the assault, and the fate of Nisibis de-pended on the event of the day. The heavy-armed cavalry, who led the van of a deep column,were embarrassed in the mud, and great num-bers were drowned in the unseen holes whichhad been filled by the rushing waters. Theelephants, made furious by their wounds, in-creased the disorder, and trampled down thou-sands of the Persian archers. The great king,who, from an exalted throne, beheld the misfor-tunes of his arms, sounded, with reluctant in-dignation, the signal of the retreat, and sus-pended for some hours the prosecution of theattack. But the vigilant citizens improved theopportunity of the night; and the return of daydiscovered a new wall of six feet in height,rising every moment to fill up the interval of thebreach. Notwithstanding the disappointmentof his hopes, and the loss of more than twentythousand men, Sapor still pressed the reductionof Nisibis , with an obstinate firmness, which