As regards Geological position, from the clear de scription of the relations of the granite to the sur rounding rocks given by Lieut. Newbold, 1 and more recently by Mr. J. C. Hawkshaw, 2 it appears that this rock forms a ridge, throwing off meta- morphic schists on the south, and passing under a newer formation of brown sandstone, which, ac cording to M. Russegger, is again found with the same characters in Upper Egypt, in Nubia, and in Sinai. 3 The granite is traversed by dykes of diorite, and the metamorpliic rocks in contact with it are composed of gneiss, generally the lowest, talc and hornblende schists, clay-slate and quartz ite ; with these are also found dykes of diorite, porphyry, and masses of serpentine. The analysis of a large piece of the granite obtained from the Egyptian Museum in the Louvre has already been given (p. 28). Whether we consider its antiquity, or the noble monolithic works of art of which it has formed the material, we must allow the granite of Egypt to be the most remarkable of all building or orna mental stones. We cannot but admire the skill and labour which have been expended in quarry ing these huge blocks, in covering them with 1 Journ. Geol. Soc. Load. vol. iv. 328. 2 Ibid. vol. xxii. 115. 3 Reisen in Europa, Asien und Afrika.