The second region, or Arabia Deserta, is bounded on the north and north-east by the Euphrates, on the east by a ridge of mountains which separates it from Chaldea, on the south by Arabia Felix, and on the west by Syria, Judea, and Arabia Petræa. This was more particularly the country first of the Cushites, and afterward of the Ishmaelites; as it is still of their descendants, the modern Bedouins, who maintain the same predatory and wandering habits. It consists almost entirely of one vast and lonesome wilderness, a boundless level of sand, whose dry and burning surface denies existence to all but the Arab and his camel. Yet, widely scattered over this dreary waste, some spots of comparative fertility are to be found, where, spread around a feeble spring of brackish water, a stunted verdure, or a few palm trees, fix the principal settlement of a tribe, and afford stages of refreshment in these otherwise impassable deserts. Here, with a few dates, the milk of his faithful camel, and perhaps a little corn, brought by painful journeys from distant regions, or plundered from a passing caravan, the Arab supports a hard existence, until the failure of his resources impels him to seek another _oasis_, or the scanty herbage furnished on a patch of soil by transient rains; or else, which is frequently the case, to resort, by more distant migration, to the banks of the Euphrates; or, by hostile inroads on the neighbouring countries, to supply those wants which the recesses of the desert have denied. The numbers leading this wandering and precarious mode of life are incredible. From these deserts Zerah drew his army of a million of men; and the same deserts, fifteen hundred years after, poured forth the countless swarms, which, under Mohammed and his successors, devastated half of the then known world.