J. MILNE ON THE SINAITIC PENINSULA AND N.W. ARABIA. 7 



stone — under the hammer the one giving a dull hollow earthy sound, 

 and the other a clear sharp metallic ring. 



Passing this bluff to the north side of the valley, we come on a 

 gradually sloping plane of sandstone, grit, and conglomerate, the 

 surface of which has been worn into a series of round hummock- 

 shaped forms, each about 4 feet in height. Winding in and out 

 between these there are smooth narrow channel -shaped hollows, 

 looking as if at times they formed courses along which water had 

 flowed ; and, in fact, down one of these a small and rapid stream of 

 water was descending, at the time of my visit, towards a palm- 

 grove which occupies the bottom of the valley. In places where a 

 cutting has been made from the valley into the hummocked plane of 

 conglomerate and sandstone, the unconformability just spoken of is 

 strikingly seen in several outliers, the tops of which are made up 

 of conglomerate, which joins in an irregular line the sandstone of 

 their lower portions. 



About three quarters of a mile up the valley, on its north side 

 there is an exposure, about 40 yards in length and from 20 to 30 

 feet in height, which exhibits a curious juxtaposition of sandstone, 

 conglomerate, and breccia. 



Not far from the place where this section is exhibited, and on the 

 same side of the valley, there are the ruins of a temple called by the 

 inhabitants the Mosque of Moses, which for the most part is built of 

 large square blocks of a fine-grained and perfectly white alabaster. 

 In the bed of the valley there were many large, tolerably angular 

 blocks of this stone, which had evidently travelled down from the 

 interior, where the inhabitants stated that at six hours' distance there 

 was a mountain or a large hill wholly composed of this material, 

 which, if like the samples seen, must be of an excellent quality for 

 building-purposes. 



A little further inland from this temple, where the valley forks, 

 the sandstone crosses to the south side, and there exposes a section 

 near 60 feet in height. On the top of this there are some 2 or 3 feet 

 of the coarse conglomerate, which lie on sandstone beds dipping 

 about 4° N.N.W. This sandstone is made up of some eighteen or 

 twenty bands of a light yellow, fine-grained, quartzose material. 

 Interstratified with these bands are one or two layers of an argilla- 

 ceous shelly material, one of which contains several narrow veins of 

 gypsum, each about half an inch in thickness, and, lower down the 

 valley, also a decided quantity of common salt. 



RoeJcs from Maclian. 



(All these, unless specially mentioned, were obtained from dykes traversing the 

 granite. The first four were determined microscopically.) 



1. Basalt, fine-grained, and of a greyish colour. 



2. Diabase, fine-grained, even-textured, dense, and of a blackish green colour. 



3. Diabase, only differs from No. 2 in being slightly greener and of a finer 



texture. 



