GEOLOGY. 395 



the same remarkable appearances, a circumstance which 

 has induced some naturalists to call it marmor embusca- 

 tum, or bushy marble. It was this singular feature that 

 led Buxtorf to derive the name of Sinai from the bushes 

 (the tamarisks and acacias) figured in the rocks ; although 

 it seems more natural that the appellation should have ori- 

 ginated from the shrubs themselves, as they are known 

 to abound in these deserts.* Shaw noticed some branches 

 of this fossil tamarisk that were nearly half an inch in 

 diameter: the constituent matter appeared rather of a 

 mineral substance, not unlike the powder of lead-ore, 

 which crumbled into dust when touched or rubbed with 

 the fingers. The porphyry, he says, is sometimes of so 

 small and compact a grain that the contexture is not in- 

 ferior to the ophites or serpentine marble ; and he thought 

 it probable, that out of this rock were hewn the two tables 

 of the law on which the Ten Commandments were writ- 

 ten with the finger of God. 



On the shore towards Akaba rise numerous promonto- 

 ries of black trap and basalt, the bases of which have 

 been scooped by the sea into creeks, resembling small 

 lakes with very narrow entrances. Some of these cliffs, 

 which run close by the water's edge for upwards of a 

 mile, present granite and red porphyry crossing each other 

 horizontally or perpendicularly in irregular layers. The 

 granite of this peninsula exhibits the same numberless 

 varieties, and the same beautiful specimens, of red, rose- 

 coloured, and almost purple, that are to be found near 

 Es Souan and above the cataract of the Nile. The transi- 

 tions from primitive to secondary rocks, partaking of the 

 nature of greenstone or gray wacke, or hornstone and trap, 

 present also an endless diversity, the description of which 

 would only tire the patience of the reader. Om Shomar 

 consists of granite : the lower stratum is red ; at the top 

 it is almost white, so as to appear from a distance like 



* Sinai mentis nomen a sine, rubus, quod lapides invent! in ea 

 figuratum in se habuerint rubum, &c. Buxtorf in voce f73D. 

 Other commentators say that sine also signifies a breast ; and as 

 Mounts Sinai and St Catherine are the highest peaks in that quar- 

 ter, they might be so called from their likeness to that part of the 

 human body ; a derivation far less probable than the other. The 

 dendritic appearance of these rocks is mentioned by Prospero Alpino 

 (Hist Nat Egypt cap. vi. p. 147), who speaks of tne " sifices 

 sylviferae, in quibus lapidibus sylvae, herbarum, fruticum, &c. pictas 

 imagines cernuntur." 



