The majority of these nomadic Arabs were Sabians, or Star-worshipers, before the adoption of Islam. History has preserved for us the names of several tribes who paid divine honors to single planets, or conspicuous fixed stars. No wonder that they should have fallen into such idolatry! The dust raised by the desert wind, which, as a rule, only blows during the day, and the heat of the sun compel them to pasture their herds and to undertake their hostile expeditions during the night. Leisure and necessity bid them gain information by directing their gaze at the starry sky, which is presented to them in a splendor of which we in our northern regions can scarcely form any idea. Since, therefore, the aborigines must have noticed at an early period that the nearly regular succession of changes in their climate took place in conformity with the annually recurring phenomena of the fixed stars, they ascribed to the latter a divine power. Thus originated the worship of the stars; and this once established, no other motives were needed to induce them to devote their constant attention to the starry skies. One result of this was that they applied proper names to the most conspicuous stars and groups of stars which were borrowed partly from the animal world around them, partly from their simple household effects, partly from various qualities and circumstances which they noticed in the stars. One tribe selected one name; another, another; and so it came to pass that one star, or group of stars, frequently bears more than one name. When, on the other hand, stars no less bright bear no names at all, the probable reason is that only fragments of the astronomical nomenclature of the Arab nomads have come down to us. After this terminology had been transmitted by oral tradition, and especially by folk-songs, for hundreds, perhaps thousands, of years in its original condition, it was combined into an entirely heterogeneous mass—that variegated mixture which we find in the works of Kazwini, Ulug Bekh, and others. When the Arabs in their fanatic zeal for the spread of Mohammed’s doctrines had conquered a great part of Asia, Africa, and Europe, and established in the heart of the ancient world a mighty empire, they adopted from the Greeks, with whom they had now come in contact, their astronomy among other sciences, and with it the Greek constellations and their method of distinguishing the stars according to their position in the figures.[15] Their astronomers now generally discriminated between the two classes of names in attributing the one to the Arabs, the other to the astronomers.