6 Mr. W. J, Hamilton and Mr. H. E. Strickland, on the Geology of 



or are wholly of the latter colour. Thin seams of mica often pervade the marble, which is then capable 

 of being split into slabs ; and they greatly assist the labours of the stone-mason. The vast abundance of 

 marble in Asia Minor enabled its ancient inhabitants to carry architecture and sculpture to their highest 

 perfection ; and the numerous antiquities which remain in this interesting country, prove that in these 

 arts the Asiatic Greeks fully equalled their kinsmen of Europe. 



The quartz rock of this formation is more local than the crystalline marble. In its purest state it is 

 white with a glassy lustre, and it is identical in appearance with the quartz rock which occurs in veins. 

 Its origin however is very different, for it is distinctly interstratified with beds of micaceous schist. La- 

 minae of mica are often disseminated through the quartz, and when these predominate, the rock passes 

 into regular micaceous schist. 



As might be expected in formations of such antiquity, the stratification of this 

 group is very irregular, both as to the amount and direction of the dip. The 

 strike however is more constant, and commonly coincides with that of the moun- 

 tain-range in which the observation is made. 



The following are the principal localities where rocks of this group are exhi- 

 bited : 



(a.) The island of Proconnesus {sea of Marmora), N. of the granitic ridge of 

 Cyzicus. — Large quarries of white marble exist here, and have given the modern 

 name of Marmora to the island, as well as to the adjoining sea, 



(6.) Cyzicus. — Near Erdek (ancient Art aki), at the south-western extremity of 

 the promontory of Cyzicus, thick beds of argillaceous schist and crystalline mar- 

 ble occur, having a S. and S.W. dip. The upper portion of the promontory of 

 Melanos, a mile S.S.W. of Erdek, consists of crystalUne marble dipping S.W. and 

 resting upon beds of argillaceous schist. The dip is quaquaversal, and evidently 

 caused by the granite which forms the central mass of the Cyzicene peninsula. 



(c.) Aidinjik, S. of Cyzicus (PI. III. Sec. 1). — The strata here present a steep 

 escarpment to theN., rising to the height of 900 or 1000 feet, while the hill slopes 

 much more gradually to the S. down to the lake of Maniyas. The summit of these 

 hills consists of a fine-grained crystalline marble, extensively quarried a little further 

 eastward, whence marble was probably obtained to supply the wants of Cyzicus, 

 one of the most splendid cities of antiquity in point of architectural decoration. 

 The marble is interstratified with beds of schist of various colours, red, black, 

 purple, yellow, and white, the whole dipping S. and S.E. by S. at angles of 70° 

 or 80°. 



(d.) Mount Olympus of Mysia (PI. III. Sec. 2). — We did not ascend to the sum- 

 rait of this precipitous mountain. It appears however from the evidence of 

 several travellers*, that a part at least of its loftier regions is composed of grey 



* Fontanier, Voyages en Orient, Paris, 1829, p. 92. Seetzen, quoted in Walpole's Travels in the 

 East, p. 113. M. Texier's personal communications. 



