1132 Capt Newbolds Geological Specimens. [No. 132. 



fossiliferous limestone ; in the age of which there may probably 

 be some difference ; though neither of them can be very ancient. 



4. Variety of Egyptian pebble. 



5. Nummulites, limestone of the Mokattem, used in the construc- 

 tion of the Pyramids. It is singular that the oldest monu- 

 ments reared by the hands of man should be built chiefly 

 of a rock of yesterday, in a geological point of view. Besides 

 these nummulites, which are exceedingly numerous, and noticed 

 by Herodotus, who mistook them for petrified lentils eaten by 

 the workmen, there are embedded echini, spatangi, crabs, 

 ostrea, fishes' teeth, hippurites, turrilited shells, and numer- 

 ous others, both bivalved and univalved. From the back of 

 the great sphinx, itself excavated from the limestone of the 

 Libyan range in situ, was quarried a block imbedding a 

 fossil reed, hollow, jointed and striated exteriorly, nearly half 

 an inch diameter. Rows of flint, resembling, in the manner 

 in which they are imbedded, those of our chalk formations, and 

 beds of fossil ostrea, occur in the limestone of the Thebaid ; 

 and the celebrated crystalloid, the morpholites or occellated 

 stones of Ehrenberg are scattered on the chalk-like soil of 

 Upper Egypt. Crystallized sulphur, bituminous lignite, mineral 

 bitumen and petroleum are found in the calcareous beds of 

 Ezzut. Sulphate of barytes near Cairo. Rock crystal, sele- 

 nite, and rock salt, arragonite, calc spar and stalagmite are 

 pretty generally distributed. The largest and finest known 

 deposit of the latter, called oriental alabaster, is situated 

 near Benihassan. 



6. Iron slag from the ruins of Arsinoe ; curious, as indicating 

 that this metal was reduced in Egypt, if not in the time of the 

 Pharaohs, at least during the Roman sway. 



7. Red porphyry — Mount Sinai. 



8. Iron ore from Hammamet — Desert of Thebaid. 



9. Shell limestone, tertiary, of Malta. 



10. Cellular basalt, from Aden. The whole of Aden, except a 

 few recent calcareous deposits, is a mass of lava passing into 

 trachyte, claystone porphyry, and pitchstone, penetrated by 

 dykes of a more recent lava. The town itself stands on 



