Geology of part of Asia Minor. 587 



be traced to the very foot of Mount Argaeus, although it cannot be supposed 

 that the whole of the volcanic matter has been derived from Hassan Dagh. 



4thly. The period when the valley between Hassan Dagh and the table-land 

 was hollowed out ; and 



Sthly. The period (which is the third of volcanic activity) when the nume- 

 rous cones at the foot of the mountain were produced, and from one of which a 

 stream of black vesicular and scoriaceous lava has flowed. This is a period 

 comparatively modern, and subsequent to the time when the surface of this 

 portion of the earth had assumed its present configuration. 



Notwithstanding the constant melting of the snows on Hassan Dagh, I was 

 surprised at not finding a single stream flowing down its side. At the head 

 of the valley, however, a rapid rivulet rushes along a deep and broken ravine 

 from the eastward, through the mass of trachytic conglomerate, which forms 

 the termination of the valley of Akserai. This stream issues from a deep 

 and narrow lake situated amongst the low hills of trachytic conglomerate, 

 close to the northern foot of the mountain, and is supplied from many copious 

 springs which rise at the foot of the mountain, in the village of Khalvardere. 

 It would appear that, as the snow melts, the water is absorbed by the porous 

 volcanic rocks, and percolating through them, emerges at the foot of the 

 mountain in the beautiful springs of cold sparkling and filtered water. 



The hills of red and yellow sandstones and grits, which rise to the north of 

 Akserai, and form the northern boundary of the valley, extend in a north-west 

 direction to the shores of the Lake of Touzla or Kodj-hissar. A considerable 

 river, cafled the Beas Su (White Water), issues from a deep gor^e directly 

 behind the town, and flowing W.N.W. through the plain, is ultimately lost 

 in the flat saline marshes^ which form the eastern boundary of the Salt Lake. 

 Owing to the nature of the country and the want of fresh water, it was im- 

 possible to examine these hills, as I might have done at a diff'erent season ; 

 and the road through the plain is generally four or five miles from them. 

 They appeared to consist of the same formation the whole way. About twenty 

 miles from Akserai, where they approach the lake, and between which and 

 the hills the road passes along a narrow slip of low, half-cultivated land, I had 

 an opportunity of more closely examining their structure. 



They consistprincipally of a brown sandstoneconglomerate, dipping nearly 

 south ; but several hard beds of conglomerate or grit, some of which contain 

 much calcareous matter, are interstratified with softer beds of thinly laminated 

 sandstone, slighlty micaceous. In some places, the sandstone becomes yel- 

 lowish, and contains a few bands of indurated shales, the whole of which 



VOL. V. SECOND SERIES. 4 G 



