In October and November, 1917, about the time of the third battle of Gaza, the Turks were still in Maan, and tried to assume the offensive against the Arabs, but proved too weak to succeed. After the fall of Jerusalem, the Turks withdrew to some extent, and the Arabs advanced towards the lands east of the Dead Sea. From this period forward, the history of the Hejaz revolt merges in that of the Palestine campaign. The Arab forces east of the Dead Sea afforded a safeguard against any possible Turkish attempt to move round our right flank and raid our line of communications. In February and in March, 1918, Turkish expeditions moving against the Arab forces of the King of the Hejaz southward from Kerak, near the south-eastern corner of the Dead Sea, met with failure. The former expedition ended in disaster, and the latter was forced to withdraw, owing to the imminence of a British crossing of the Jordan in its rear. Arab activity on the railway now definitely isolated Medina. Although the Arabs were never strong enough to push a powerful force up through Eastern Palestine, yet the presence of a friendly force operating in that country exercised considerable influence upon the later stages of the Palestine campaign. The assistance which the Arabs gave in the ultimate destruction of the Turkish army was invaluable. CHAPTER IV PALESTINE The story of a campaign is more interesting if we have a general idea of the topography of the country in which it is conducted. Our time will, therefore, not be wasted if we leave the British Army on the frontiers of the Holy Land for a few minutes longer and form a mental picture of the terrain over which they are about to operate. Picture a country, about the size of Wales, divided into parallel strips running north and south, zones of alternate elevation and depression. This will give a rough idea of the conformation of Southern Palestine. On the west is the Mediterranean Sea. Skirting the sea are a series of sand dunes, beyond which comes the Coastal Plain. Together, these form the first depressed strip, averaging about 15 miles in width. Northwards, it tapers to a point where the mountains reach the sea at Cape Carmel. Beyond the Coastal Plain is the range of mountains on which stands Jerusalem, the mountains of Samaria and of Judaea, rising to a height of about 3,000 feet above the level of the sea. On the eastern side of these mountains is a steep drop to the Valley of the Jordan and the Dead Sea, the level of the latter being nearly 1,300 feet below the level of the Mediterranean, and more than 4,000 feet below the summit of the adjoining Mount of Olives. Beyond the Jordan valley the country rises again abruptly into the hills of Moab or Eastern Palestine. Beyond lies the waterless desert.