J. MILNE ON THE SINAITIC PENINSULA AND N.W. ARABIA. 25 



pale maroon-coloured) sandstone. In the portion examined this was 

 made up of a fine-grained quartzose material, containing a small 

 quantity of lime, probably derived by infiltration from the calca- 

 reous beds with which it is so closely associated. One exception to 

 the colour of these beds was seen in a soft and friable yellow band. 

 The left side of the road, which is here in part an artificial formation, 

 is built up of blocks of red sandstone, which were obtained in large 

 regularly squared oblong masses by undermining several overhang- 

 ing beds upon the right. In these red beds, as might perhaps have 

 been anticipated, no trace of organic remains could be seen. 



On nearing the summit of the tableland of the Tih, which by baro- 

 metrical observation is about 2000 feet above the sea-level, a view 

 looking down into a north- and-south gorge showed the relation of 

 the red sandstones to the limestones before described. Upon the 

 east flat surfaces of limestone were seen dipping sharply towards the 

 east ; and from these scarps, and especially from the one forming 

 the right-hand wall of this north- and- south gorge, it would appear 

 as if they once covered over the nearly horizontal sandstones on 

 the left. 



Descent of the Tih. — The striking feature of this desert plateau, 

 when approached from the Akaba side, is its wonderful evenness of 

 surface, which, from the fineness of the material with which it is 

 covered, gives it an appearance not unlike an immense expanse of 

 gravel walk. This material consists in great part of white quartz 

 pebbles, which are intermingled with fine-grained porphyries and 

 other felspathic rocks derived from some low peaks several miles 

 away to the north. About eighteen miles across this flat country, at 

 Turf er Eukn, the track enters between low hills forming the 

 southern boundary of this great tableland, the surface-contour of 

 which, at this point, is represented by the letter V, the arms of 

 which form a shallow trough-like drainage- area, one arm trending 

 N.W. towards the Mediterranean, and the other to the N.E., towards 

 the southern continuation of the Dead Sea, whilst the apex of the 

 two is to the south. 



Turf er Rukn, which is continued towards the north as a low 

 and almost imperceptible rise of ground forming the water-parting 

 between the Y-shaped arms of the Tih, further to the south rises 

 about 400 feet above the plain as a long scarp of yellow lime- 

 stone. Near the foot of the southern end of this scarp there is a 

 small exposure of a yellowish sandstone, and also indications of 

 a band of siliceous haematite running in a direction about one 

 point to the south of west. This ore is easily distinguished by its 

 dark colour, which contrasts strongly with the light-coloured sand 

 on which it lies. 



Beyond this, upon the right or north side of the road, there are 

 some low ridges consisting of bands of limestone dipping towards the 

 north. Intercalated with these bands are layers of flint which, on 

 their exterior, very much resemble some dark-coloured portions of 

 the rock in which they are imbedded. 



This character of country, of limestone scarps on the left, and low 



