The principal work carried out by the XXth Corps during the period of concentration consisted in laying the standard gauge line to Imara and opening the station at that place on October 28; prolonging the railway line to a point three-quarters of a mile north-north-east of Karm, where the station was opened on November 3; completing by October 30 the light railway from the east bank of the wadi Ghuzze at Gamli _via_ Karm to Khasif; and developing water at Esani, Malaga, and Abu Ghalyun for the use first by cavalry detachments and then by the 60th Division. Cisterns in the Khasif and Imsiri area were stocked with 60,000 gallons of water to be used by the 53rd and 74th Divisions, and this supply was to be supplemented by camel convoys. Apparently the enemy knew very little about the concentration until about October 26, and even then he could have had only slight knowledge of the extent of our movements, and probably knew nothing at all of where the first blow was to fall. In the early hours of October 27 he did make an attempt to interfere with our concentration, and there was a spirited little action on our outpost line which had been pushed out beyond the plain to a line of low hills near the wadi Hanafish. The Turks in overwhelming force met a most stubborn defence by the Middlesex Yeomanry, and if the enemy took these London yeomen as an average sample of General Allenby's troops, this engagement must have given them a foretaste of what was in store for them. The Middlesex Yeomanry (the 1st County of London Yeomanry, to give the regiment the name by which it is officially known, though the men almost invariably use the much older Territorial title) and the 21st Machine Gun Squadron, held the long ridge from El Buggar to hill 630. There was a squadron dismounted on hill 630, three troops on hill 720, the next and highest point on the ridge, and a post at El Buggar. At four o'clock in the morning the latter post was fired on by a Turkish cavalry patrol, and an hour later it was evident that the enemy intended to try to drive us off the ridge, his occupation of which would have given him the power to harass railway construction parties by shell-fire, even if it did not entirely stop the work. Some 3000 Turkish infantry, 1200 cavalry, and twelve guns had advanced from the Kauwukah system of defences to attack our outpost line on the ridge. They heavily engaged hill 630, working round both flanks, and brought heavy machine-gun and artillery fire to bear on the squadron holding it. The Royal Flying Corps estimated that a force of 2000 men attacked the garrison, which was completely cut off.