Detailed maps had been issued, not only of the Turks' position at Ctesiphon, but also of Bagdad and the methods to be adopted to push the enemy through and out of the city. At Lajj we were about nine miles from the Arch of Ctesiphon, built by Chosroes I. in the 6th cent. B.C. and round which battles had been fought from time immemorial. From the top of a sand-dune near general headquarters, the magnificent ruin was clearly visible standing up gaunt and alone above the flat plain. The Turks' position surrounded the Arch and stretched back on both banks of the river. We bivouacked one night at Lajj and at nine o'clock the following evening--Sunday, November 21st--the final advance began. Our plan was to surround and defeat the Turks on the left bank, where the greater part of their forces lay, and to drive them back on the Tigris or Diala River. The force was split into four columns, which were to attack from different angles, the "Flying" column being deputed to complete the victory by dashing on to Bagdad and seizing the Bagdad end of the Samarra Railway. At midnight we reached our station on some sand-hills about four to five miles due east of the Arch, which we could see very clearly as soon as it became light. It was a bitterly cold night and after digging in we lay down to get what sleep we could before dawn broke. The attack was to be begun by the columns further north, who had had a longer march and were further round the Turkish flank. There appeared to be considerable delay on their part, and it was an hour after the advertised time when our advance began. In the meantime a troop of Turkish cavalry had come out on a reconnaissance, but had thought better of coming up as far as our sand-hills and, after hesitating, retired unmolested by us. As we debouched from the high ground, we could see masses of Turks, apparently retiring in orderly formation towards their second line or still further, and the thought occurred that they were not going to wait even for us to attack. Actually, however, these were troops from the other side of the river being hastily brought across to strengthen the Turkish reserves opposite to us.