On the 18th of September, the day before the attack, a large force of bombing aeroplanes was directed over Nablus, where it was known the enemy had his main telephone and telegraph exchange. This was completely destroyed, a fact which played an important part in enabling our cavalry to reach the Plain of Esdraelon next day, before the enemy G.H.Q. knew they had broken through.
The striking success of these measures was afterwards proved by captured enemy documents. Among these was the German Intelligence Service map, issued on the very day before our attack commenced. This map shows three cavalry divisions still in the Jordan Valley, and only one in the coastal sector. Only two infantry divisions are shown in the coastal sector instead of five, and the whole map points to an attack in, or east of, the Jordan Valley. A German air reconnaissance report, dated 17th of September, and found among Liman von Sanders' papers at Nazareth, stated that 'far from there being any diminution in the cavalry in the Jordan Valley, there are evidences of twenty-three more squadrons there.'
The Turkish line on the plain consisted of two defensive positions, well constructed and heavily wired. The first, 14,000 yards in length and 3000 in depth, ran along a sandy ridge in a north-westerly direction from Bir Adas to the sea. It consisted of a series of works connected by a continuous network of fire trenches. The second, or El Tire system, 3000 yards in the rear, ran from the village of that name to the mouth of the Nahr el Falik. On the enemy's extreme right the ground, except for a narrow strip along the coast, was marshy, and could only be crossed in few places. The defence of the second system did not, therefore, require a large force.
The attack of these positions was entrusted to the 21st Corps (3rd, 7th, 54th, and 75th Divisions), to which were also attached the 60th Division, the French Infantry Detachment, and the 5th A.L.H. Brigade (Australian Mounted Division), together with a large number of heavy guns and two brigades of mountain artillery. This force was to break through the enemy's defences between the railway and the sea, in order to open the door for the cavalry, and, at the same time, to seize the foothills south-east of Jiljulie. The Corps was then to swing to the right, pivoting on Jiljulie, as already explained, on to the line Hableh-Tul Keram, and advance in a north-easterly direction, converging on Samaria and Attara (on the Jenin-Samaria Railway about five miles north-west of the latter place), so as to drive the enemy up the two roads from Messudieh Junction and Samaria to Jenin, into the arms of the cavalry on the Plain of Esdraelon. The 5th A.L.H. Brigade was to cover the outer (left) flank of the Corps during this turning movement, capture Tul Keram station, and then raid and cut the Messudieh-Jenin Railway, near Ajje.
As soon as the infantry had broken through, the three cavalry divisions were to advance rapidly up the plain, the 5th Division along the coast road, through Mukhalid, the 4th via Tabsor and Mughair, and the Australian Mounted Division following the 4th.
The enemy had partially prepared an entrenched position across the plain from about Jelameh, through El Mejdel and Liktera, to the sea near the mouth of the Nahr Mefjir, and this was known to be held by a few troops. The 4th Division had orders to seize the portion of this line between Jelameh and Liktera, while the 5th dealt with the western half from Liktera to the coast.
Having made good the line of the Nahr Mefjir, they were to turn north-east and cross the Carmel Range, the 4th and Australian Divisions by the Musmus Pass, and the 5th by a little-known track from Sindiane to Abu Shusheh, and enter the Plain of Esdraelon. Arrived on the plain, the 4th Cavalry Division was to seize Afule and then push rapidly down the Valley of Jezreel to Beisan, occupy the Jordan bridges there, and send a force to hold and, if necessary, destroy the bridge at Jisr Mejamieh, twelve miles farther north. This programme entailed a ride of ninety-seven miles on end, and included the crossing of a mountain range by a difficult pass.
The 5th Division was directed on Nazareth (seventy miles) to capture the enemy General Headquarters, which was located there, and, if possible, Liman von Sanders himself, and then clear the plain as far east as Afule. The Australian Division was to remain on the Plain of Esdraelon at El Lejjun, sending a force to Jenin (sixty-eight miles), to intercept the Turks retiring from Samaria, when that place had been captured by our infantry.
As these immense distances had to be covered in one 'bound,' speed was essential. The 4th and 5th Divisions, were, therefore, ordered to move up the coast on a wide front, and sweep over the Jelameh-Liktera positions with the sword and lance. If unexpectedly strong opposition was encountered there, the Australian Division was available, immediately in rear, to reinforce. The crossing of the Carmel Range was to be carried out as rapidly as possible, as it was recognised that our troops could only move in very narrow columns over the mountains, especially through the Musmus Pass, and flank guards would be out of the question. The 5th Division was, however, directed to drop a small force on the Sindiane-Abu Shusheh track, at the top of the range, to protect the left flank of the other two divisions, while they were passing through the defile.
The 20th Corps, in the hills north of Jerusalem, was ordered to attack all along its front on the day after the attack in the coastal plain, and drive the enemy northwards into the arms of the cavalry, while, in the Jordan Valley, Chaytor's Force had first to seize the bridge over the river at El Damieh, and then to cross the Jordan for the third and last time, and advance on Amman.