The Persians now for the first time appeared in force. As Julian drew near the great stream, he perceived that his passage of it would not be unopposed. Along the left bank, which was at this point naturally higher than the right, and which was further crowned by a wall built originally to fence in one of the royal parks, could be seen the dense masses of the enemy's-horse and foot, stretching away to right and left, the former encased in glittering armor, the latter protected by huge wattled shields. Behind these troops were discernible the vast forms of elephants, looking (says the historian) like moving mountains, and regarded by the legionaries with extreme dread. Julian felt that he could not ask his army to cross the stream openly in the face of a foe thus advantageously posted. He therefore waited the approach of night. When darkness had closed in, he made his dispositions; divided his fleet into portions; embarked a number of his troops; and, despite the dissuasions of his officers, gave the signal for the passage to commence. Five ships, each of them conveying eighty soldiers, led the way, and reached the opposite shore without accident. Here, however, the enemy received them with a sharp fire of burning darts, and the two foremost were soon in flames. At the ominous sight the rest of the fleet wavered, and might have refused to proceed further, had not Julian, with admirable presence of mind, exclaimed aloud--"Our men have crossed and are masters of the bank--that fire is the signal which I bade them make if they were victorious." Thus encouraged, the crews plied their oars with vigor, and impelled the remaining vessels rapidly across the stream. At the same time, some of the soldiers who had not been put on board, impatient to assist their comrades, plunged into the stream, and swam across supported by their shields. Though a stout resistance was offered by the Persians, it was found impossible to withstand the impetuosity of the Roman attack. Not only were the half-burned vessels saved, the flames extinguished, and the men on board rescued from their perilous position, but everywhere the Roman troops made good their landing, fought their way up the bank against a storm of missile weapons, and drew up in good order upon its summit. A pause probably now occurred, as the armies could not see each other in the darkness; but, at dawn of day, Julian, having made a fresh arrangement of his troops, led them against the dense array of the enemy, and engaged in a hand-to-hand combat, which lasted from morning to midday, when it was terminated by the flight of the Persians. Their leaders, Tigranes, Narseus, and the Surena, are said to have been the first to quit the field and take refuge within the defences of Ctesiphon. The example thus set was universally followed; and the entire Persian army, abandoning its camp and baggage, rushed in the wildest confusion across the plain to the nearest of the city gates, closely pursued by its active foe up to the very foot of the walls. The Roman writers assert that Ctesiphon might have been entered and taken, had not the general, Victor, who was wounded by a dart from a catapult, recalled his men as they were about to rush in through the open gateway. It is perhaps doubtful whether success would really have crowned such audacity. At any rate the opportunity passed--the runaways entered the town--the gate closed upon them; and Ctesiphon was safe unless it were reduced by the operations of a regular siege.