Crassus had under his command no contemptible force--seven legions, 4,000 cavalry, and an equal number of light-armed troops. The first reports that reached him represented the enemy as shrinking from the contest. This notion was confirmed by an Arab chief, Abgarus of Edessa, who was believed to be friendly to Rome. He had certainly done good service to Pompey, but he was now acting in the interest of the Parthian king. He urged on Crassus an immediate advance; the enemy, he declared, were already removing their most valuable property to a place of safety. This was all false. The Parthian king with half his army was ravaging Armenia; his commander-in-chief had been detached with the other half to deal with Crassus. The Romans moved forward with all the haste that they could compass. Day after day they advanced, but no enemy could be seen. At last some horsemen were descried in the distance, and Abgarus was sent on in advance to reconnoitre. He did not return, and the army again moved forwards. Their march brought them to a river called the Balissen. Crassus was advised by his staff to halt and encamp. He was too impatient to listen to this counsel, and still advanced. It was not long before he came in sight of the enemy. At first sight the Parthian host did not seem very formidable. It did not display any of the pomp and circumstance of war, and its numbers had been carefully concealed. Then by a sudden movement the banners of glistening silk embroidered with gold were displayed, and the helmets and coats of mail glittered in the sun, the drums giving out all the time a terrific volume of sound. Never before had the Romans encountered a similar enemy. It was a host of cavalry which they had to meet, most of them archers, both man and horse being protected with armour made sometimes of iron, sometimes of leather. The Romans were taken at a terrible disadvantage. All their tactics, especially the close order in which they were accustomed to fight, told against them, whilst their light-armed troops were hopelessly outnumbered. The younger Crassus was sent forward by his father with a picked force, in the hope that he might relieve the legions of the brunt of the attack. The enemy retreated before him, but when they had lured him on out of sight or reach of the main army they turned upon him. He had no choice, so overwhelming were their numbers, but to fall back before them. He made a stand at a hill, on the sloping side of which he ranged what troops remained to him. But the ranks rising one above another offered a broader target to the Parthian archers. Nearly the whole force perished, Crassus and his officers by their own hands. Five hundred were taken prisoners; none escaped. The first knowledge that the elder Crassus had of his son's fate was the sight of his head on a pole. The attack upon the legions was renewed again and again until darkness brought a temporary relief. During the night the Romans retreated, and reached Carrhæ in safety.