EVENTS IN IRAC--MOTHANNA AND THE PERSIANS--NEED OF REINFORCEMENTS. Moharram--Jumâd, A.H. XIII. March--August, A.D. 634. [Sidenote: Mothanna attacked by the Persians.] After bidding Khâlid farewell, Mothanna returned to Hîra, and made the best disposition of his small force that he could, so as to strengthen his defences towards the Persian capital. That the position was not altogether secure is shown by the precaution of Khâlid, just before his departure, in sending the sick and infirm with the women and children home, for the time, to Arabia. A new prince, Shahrîrân, had succeeded to the throne; and he now thought to expel the invaders by sending an army under Hormuz, 10,000 strong, against them.[176] Mothanna, having timely warning, immediately called in his outlying garrisons, but, with every exertion, the force brought together was dangerously small in comparison with the Persian host. The king, confident of victory, wrote to Mothanna an insulting letter that ‘he was about to drive him away with an army of fowl-men and swine-herds.’ Mothanna answered: ‘Thou art either a braggart or a liar. If what thou sayest be true, then blessed be the Lord that hath reduced thee to such defenders!’ Having despatched this reply, he advanced boldly to meet Hormuz. Leaving Hîra, the little force passed under the dreary ruin of Birs Nimrud, and crossing the Euphrates, encamped to the north of the vast mound which marks the site of Babylon. [Sidenote: Battle of Babylon. A.H. XIII. Summer, A.D. 634.] There, some fifty miles from the capital, amid a network of canals watering the country (now a wilderness or a swamp), he chose the battle-ground; and, placing his two brothers in charge of either wing, himself at the head of the centre, awaited the attack of Hormuz. The Persian line was preceded by a war-elephant, which threw the Arab ranks into confusion, and for a while paralysed their action. Mothanna, followed by an adventurous band, surrounded the great creature, pierced it in a mortal part, and so brought it to the ground. Deprived of this adventitious help, the enemy gave way before the fierce onslaught of the Arabs, who pursued the fugitives across the plain of Dura to the very gates of Medâin. The praises of ‘the hero of the elephant’ have been handed down in Arabian verse.[177] [Sidenote: Mothanna asks Abu Bekr for reinforcements.]