The tradition respecting this seems to have been already very confused when Genesis was compiled, for we find in chap. xv. vers. 15, 16, the Lord saying to Abraham, that his descendants shall come back to Palestine and possess the whole country from the river of Egypt to the river Euphrates, "in the fourth generation" after Abraham had "gone to his fathers in peace, and been buried in a good old age"; while only one verse before it is said, "thy seed shall be a stranger in a land that is not theirs, and shall serve them; and they shall afflict them for four hundred years." Even if 400 years were allowed for the sojourn of the Hebrews in Egypt, it would not extend the interval between Moses and Abraham to more than 500 years, or 400 years less than is required by the synchronism with Chedorlaomer. It is needless to say that neither in the fourth or in any other generation did the descendants of Abraham "possess the whole country from the river of Egypt to the river Euphrates." There is no period of Jewish history so obscure as that of the sojourn in Egypt. The long date is based entirely on the distinct statement in Genesis xii., that the sojourning of the children of Israel was 430 years, and other statements that it was 400 years, both of which are hopelessly inconsistent with the genealogies. Genealogies are perhaps more likely to be preserved accurately by oral tradition than dates and figures, which Oriental races generally deal with in a very arbitrary way. But there are serious difficulties in the way of accepting either date as historical. There is no mention of any specific event during the sojourn of the Israelites in Egypt between their advent in the time of Joseph and the Exodus, except their oppression by a new king who knew not Joseph, and the building of the treasure cities, Pi-thom and Ramses, by their forced labour. The latter fact may be taken as probably true from the monuments discovered by Mr. Flinders Petrie; and if so, it occurred in the reign of Ramses II. But there is no other confirmation, from Egyptian records or monuments, of any of the events related in the Pentateuch, until we come to the passage quoted from Manetho by Josephus, which describes how the unclean people and lepers were oppressed; how they revolted under the leadership of a priest of Hieropolis, who changed his name from Osarphis to Moyses; how they fortified Avaris and called in help from the expelled Hyksos settled at Jerusalem; how the Egyptian king and his army retreated before them into Ethiopia without striking a blow; and the revolters ruled Egypt for thirteen years, killing the sacred animals and desecrating the temples; and how, at the end of this period, the king and his son returned with a great army, defeated the rebels and shepherds with great slaughter, and pursued them to the bounds of Syria.