364 NOTES ON THE GEOLOGY 



» 



Robinson and Smith found it in descending from the prom- 

 ontory Ras el Feshkah to the plain, near the north end of the 

 sea ; and, in one instance, it formed the cement of pebbles, as if 

 it had flowed in among them. But such is often the appearance 

 of the cement of conglomerates ; and the rock in that region is 

 mostly conglomerate. I apprehend that this limestone, as well 

 as the conglomerate which it forms, were produced at the bottom 

 of waters abounding both in carbonate of lime and fluid bitu- 

 men. It occurs in large quantities on tlie west shore of the Sea 

 of Galilee, whence several thermal springs issue ; and not improb- 

 ably, a careful examination of that locality might show that it is 

 now in the course of formation, and unfold the precise mode of 

 its production. 



The compact limestone, No. 380, from Mars Hill in Athens, I 

 analyzed, partly on account of its classic locality, and partly to 

 see whether its composition agrees with that of the compact 

 limestones of Western Asia. In one hundred parts, I found 

 Earthy residuum, ....... 2.33 



Carbonate of magnesia, 0.84 



Carbonate of lime, 96.83 



100.00 



It mil be seen, by comparing the above analysis with those 

 previously given, that it corresponds closely with that of several 

 of the compact limestones of Palestine and Syria. 



The common rock of the island of Malta, Nos. 140 and 141, 

 very much resembles some of the chalky limestones of Sp'ia and 

 Palestine. But Professor Bailey could not detect in it any Poly- 

 thalamian remains ; and it may belong to a different geological 

 period. The organic remains found in it, however, would place 

 it higher rather tlian lower, in the scale of rocks. The large 

 shark's tooth. No. 250, appears almost as fresh as a recent one, 

 and probably belongs to the genus, Carcharias. No. 153 is a 

 Clypeaster, five inches in diameter, mostly converted into yel- 

 lowish calcareous spar. — {Bronii's Lethcea GeogTiostica, Tab. 

 XXXVI, fig. 9.) No. 151 is a very perfect nucleus in limestone 

 of a Cardium, or an Area ; No. 152 a similar nucleus of an Iso- 



