2. Here it may be observed, that the migrations of Abraham and his sons show the manner in which the earth was gradually covered with people. In those ages some cities had been built, and the country to some extent about them cultivated; but wide spaces of unoccupied land lay between them. A part of society following therefore the pastoral life, led forth their flocks, and, in large family tribes, of which the parent was the head, uniting both the sovereign power and the priesthood in himself, and with a train of servants attached to the tribe by hereditary ties, pitched their camps wherever a fertile and unappropriated district offered them pasture. A few of these nomadic tribes appear to have made the circuit of the same region, seldom going far from their native seats; which would probably have been the case with Abraham, had he not received the call of God to depart to a distant country. Others, more bold, followed the track of rivers, and the sweep of fertile valleys, and at length some built cities and formed settlements in those distant regions; whilst others, either from attachment to their former mode of life, or from necessity, continued in their pastoral occupations, and followed the supplies afforded for their flocks by the still expanding regions of the fertile earth. Wars and violences, droughts, famines, and the constant increase of population, continued to impel these innumerable, but at first, small streams of men into parts still more remote. Those who settled on the sea coast began to use that element, both for supplying themselves with a new species of food, and as a medium of communication by vessels with other countries for the interchange of such commodities as their own lands afforded with those offered by maritime states, more or less distant. Thus were laid the foundations of commerce, and thus the maritime cities were gradually rendered opulent and powerful. Colonies were in time transported from them by means of their ships, and settled on the coasts of still more distant and fertile countries. Thus the migrations of the three primitive families proceeded from the central regions of Armenia, Mesopotamia, and Assyria; and in succession they established numerous communities,--the Phenicians, Arabians, Egyptians, Ethiopians, and Lybians southward;--the Persians, Indians, and Chinese eastward;--the Scythians, Celts, and Tartars northward;--and the Goths, Greeks, and Latins westward, even as far as the Peruvians and Mexicans of South America, and the Indians of North America.