1868.] BAUEEMAN ARABIA PETRiEA. 35 



reduced copper-ore in the clay. The inhabitants were, however, not 

 entirely without metal, as a small bracelet of copper was found in a 

 tomb, the only one remaining unopened, in Wady Sidreh, associated 

 with lance- and arrow-heads of flint, and a necklace of beads formed 

 of spiral marine shells bored through for stringing. 



Alluvium of Ghenneh. — The alluvial deposits of the Ghenneh val- 

 leys have certain features of interest in connexion with the ancient 

 mines. The downland at the foot of the granitic escarpment is 

 covered with a gravel made up of pebbles of red, yellow, and white 

 quartz, and brown sand from the waste of the Triassic sandstones ; 

 a few pieces of fossil wood were also found. The watercourses are 

 bounded by steep and terraced cliffs, mainly of granitic detritus, of 

 a coarse but comparatively uniform grain (| inch) ; but in the cen- 

 tral valley these are bordered at lower levels by a coarser gravel, 

 with good-sized boulders, probably indicating the return of a more 

 rapidly flowing stream in later times. 



In the finer alluvium a single but unbroken shell of a large fresh- 

 water bivalve was fonnd, which, on comparLson, proves to be identical 

 with the large Anodon-like form, Spatlia Cliaziana (Lea), now living 

 in the Nile. Broken fragments of the same shell were also found in 

 the mine, accompanying the stone and wooden tools already men- 

 tioned, and apparently having been carried in by the miners for food. 

 These latter are well preserved, the nacre of the interior being fresh 

 and brilliant ; but the shell from the gravel is rongh and white, 

 having lost all trace of its original polish and colour. Unless, there- 

 fore, we suppose that these shells have been brought from the Nile, 

 which is not very likely, as the distance is about 300 miles, we must 

 admit that, in the days of the old miners, the Ghenneh plain and 

 valleys were sufficiently well watered to allow of large fluviatile mol- 

 lusca living in them. But even supposing the shells to have been 

 imported, the inference is that a great part of the gravels have 

 been deposited, and fresh channels cut through them, in the last 

 4000 years. 



Alluvium of Wady Ferran Sfc. — The evidence, however, of the 

 existence of lakes or slow-flowing rivers in Arabia Petra^a is not 

 confined to the somewhat doubtful case given above. In the upper 

 part of Wady Ferran and the higher valley of Wady el Scheick, which 

 are cut through a comparatively soft grey granitic gneiss, there are 

 considerable accumulations of fine-grained well-stratified alluvium, 

 forming terraced masses which, although much eroded by subsequent 

 action of the weather, often attain a height of from 40 to 60 feet above 

 the bottom of the valley. They have been attributed by a recent 

 traveller * to the action of glaciers, and described as moraines ; but 

 a close inspection proves them to be only ordinary lake- or river- 

 alluvium, as in places they are full of calcareous nodules (race or 

 knnkur), and also contain beds of calcareous tufa (incrusting the 

 stems of carices or plants of a similar character), as well as fresh- 

 water shells, including Lymncea truncatula and a species of Pisidium, 



* Dr. Oscar Fraas, ' Aus dem Orient. Geologische Beobachtungen am Nil, auf 

 der Sinai-Halbinsel, und in Syrien,' Stuttgart, 1867. See Anniversary Address 

 of the President (W. W. Smyth), Quart. Journ, Geol. Soc. vol. xxiv. p. 211. 



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