Going west from Petra, the valley of the _Araba_ is again entered, where the deeper _Wadi-el-Jeib_ is seen to wind along, very near the middle of it, from the south, then sweeping off NW., it meets the _Wadi-el-Jerafah_, which comes in from the SW. Afterwards, it is called only _Wadi-el-Jeib_; and being a deep valley within a larger valley, it forms the chief water-course of the greater portion of the Araba, and carries down to the Dead Sea, in the wet season, an immense body of water. El Araba, more to the north of Gebel Harun, is much wider; in parts of it there are _gravel_ hills; and here and there, masses of _porphyry_ lie about in the sand, having been washed down by the torrents. Eleven or twelve miles north of that Mount (_Hor_), occurs the pass of _Nemela_ among low hills of _limestone_, or rather a yellowish _argillaceous_ rock, the dark steep mass of the mountain being _porphyry_, as before described; thence the Wadi ascends between the porphyry and limestone formations; and on the top is a little basin of _yellow sandstone_ capping the _porphyry_. Coming back southward through the Wadi-el-Araba, as far as the _embouchure_ of the valley of the _Jerafah_--meaning "gullying,"--which is about a mile wide, the mountains on this west side are found to be composed of _chalk_ and _limestone_; and, in many places, with large pieces of black _flint_. On the north, and to the east of Lussan, the mountains of Idumæa are lofty, consisting of precipitous _limestone_ ranges; the solitary conical mount, about 600 feet above the plain, named _Gebel Araif-el-Naka_--"the crest of a she-camel," forms a conspicuous object; it is _calcareous_, and strewed with _flints_. Low ridges extend from it westward and eastward; the latter terminating in a headland or bluff, called Gebel _Makrah_. The wide sandy _Wadi-el-Ghudhagidh_--the _Ghudhaghidh_ of Robinson--is probably the _Gudgodah_; or, as it is written in Hebrew, _Ghudghodah_, mentioned in Deut. x. 7, whither the Israelites journeyed from Mosera (_Wadi Mousa_) after Aaron's death. After this valley were some low _chalky_ cliffs, and then succeeded a barren _flinty_ tract. Towards the NW. and W., a broad open district stretches out apparently to _Gebel Jaraf_, said to be 1300 feet above the sea level, through which is the course of the _Wadi Khereir_, elevated about 1000 feet at its nearest point to that mount, and flowing northward into the large _Wadi-el-Agaba_,--upon one side, and to _Gebel Yelak_, the "white mountain," on the other side; but it is broken in some places by _limestone_ or _chalk_ hills.