Page:Mount Seir, Sinai and Western Palestine.djvu/220

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NARRATIVE OF AN EXPEDITION THROUGH ARABIA PETRÆA,

and corals were found round the camp of the 3rd December at an elevation of about 130 feet above the Gulf of Akabah.

These ancient sea beds are represented in the Egyptian area by the old coast-line of 220 feet, discovered by Fraas along the flanks of the Mokattam Hills above Cairo, and recently described by Schweinfurth. (Über die geol. schichtungliederung d. Mokottam bei Cairo; Zeit. d. Deuts. Geol. Gesel, 1883.) The period in which the sea rose to this level may be stated in general terms as the Pliocene, but it continued downwards till more recent times; and the author believes that at the time of the Exodus the Gulf of Suez reached as far as the Great Bitter Lake (Quarterly Statement, April, 1884). It is scarcely necessary to observe that throughout the longer portion of this period of submergence Africa was disconnected from Asia.

8. The Miocene period is not represented by any strata throughout the district traversed by the Expedition. The author considers that in this part of the world the Miocene period was one of elevation, disturbance, and denudation of strata; not of accumulation. To this epoch he refers the emergence of the whole of the Palestine, and of the greater part of the Sinaitic areas, from the sea, in which the Cretaceo-nummulitic limestone formations were deposited. To the same epoch also he considers the faulting and flexuring of the strata is chiefly referable; and notably the formation of the great Jordanic line of fault, with its branches and accompanying flexurings of the strata—which are very remarkable along the western sides of The Ghôr. These phenomena were accompanied and followed by extensive denudation, and the production of many of the principal physical features of the region referred to.

9. The evidences of a Pluvial period throughout this region are to be found (a) in the remains of ancient lake beds, (b) in the existence of terraces in the river valleys, (c) in the great size and depth of many valleys and gorges, now waterless except after severe thunderstorms, and (d) in the vastly greater size of the Salt Sea (or Dead Sea), which must have had a length of nearly 200 English miles from north to south, at the time when its surface was at a higher level than that of the Mediterranean at the present day. The author considers that this Pluvial period extended from the Pliocene through the post-Pliocene (or Glacial) down to recent times. As it is known, from the observations of Sir J. D. Hooker, Canon Tristram, and others, that perennial snow and glaciers existed in the Lebanon during the Glacial epoch, the author infers