Thus, only the southern interior of the peninsula remains to be visited. The name given to it by the Arabs, _Roba el-Khaly_, “the abode of emptiness,” no doubt describes its character. It is an immense, undulating, sandy waste, dotted with scarce and small oases, which give water and shelter to the Bedouins, but without any large tract of habitable land, and consequently without cities, or other than the rudest forms of political organization. CHAPTER II. EARLY EXPLORERS OF ARABIA. WHEN the habit of travel began to revive in the Middle Ages, its character was either religious or commercial, either in the form of pilgrimages to Rome, Palestine, (whenever possible), and the shrines of popular saints, or of journeys to the Levant, Persia and the Indies, with the object of acquiring wealth by traffic, the profits of which increased in the same proportion as its hazards. From the time of Trajan’s expedition to Arabia, (in A.D. 117) down to the sixteenth century, we have no report of the history or condition of the country except such as can be drawn from the earlier Jewish and Christian traditions and the later Mohammedan records. The first account of a visit to Arabia which appears to be worthy of credence, is that given by Ludovico Bartema, of Rome. After visiting Egypt, he joined the caravan of pilgrims at Damascus, in 1503, in the company of a Mameluke captain, himself disguised as a Mameluke renegade. After several attacks from the Bedouins of the desert, the caravan reached Medina, which he describes as containing three hundred houses. Bartema gives a very correct description of the tomb of the Prophet, and scoffs at the then prevalent belief that the latter’s coffin is suspended in the air, between four lodestones.