The retreat commenced on June 16. Scarcely were the troops set in motion, when an ominous cloud of dust appeared on the southern horizon, which grew larger as the day advanced; and, though some suggested that the appearance was produced by a herd of wild asses, and others ventured the conjecture that it was caused by the approach of a body of Julian’s Saracenic allies, the emperor himself was not deceived, but, understanding that the Persians had set out in pursuit, he called in his stragglers, massed his troops, and pitched his camp in a strong position. Day-dawn showed that he had judged aright, for the earliest rays of the sun were reflected from the polished breastplates and cuirasses of the Persians, who had drawn up at no great distance during the night. A combat followed in which the Persian and Saracenic horse attacked the Romans vigorously, and especially threatened the baggage, but were repulsed by the firmness and valor of the Roman foot. Julian was able to continue his retreat after a while, but found himself surrounded by enemies, some of whom, keeping in advance of his troops, or hanging upon his flanks, destroyed the corn and forage that his men so much needed; while others, pressing upon his rear, retarded his march, and caused him from time to time no inconsiderable losses. The retreat under these circumstances was slow; the army had to be rested and recruited when it fell in with any accumulation of provisions; and the average progress made seems to have been not much more than ten miles a day. This tardy advance allowed the more slow-moving portion of the Persian army to close in upon the retiring Romans; and Julian soon found himself closely followed by dense masses of the enemy’s troops, by the heavy cavalry clad in steel panoplies, and armed with long spears, by large bodies of archers, and even by a powerful corps of elephants. This grand army was under