of the Neighbourhood of Smyrna . 40 1 



§. 3. Trachytic Rocks. — These extend westward from the torrent of 

 Bournabat to the mouth of the Hermus, and compose, as before stated, the 

 whole mountain of Cordileon. The prevailing rock is a reddish brown tra 

 chyte, identical with that of Smyrna, and, like it, is occasionally divided into 

 laminae resembling strata. 



The junction of these rocks with the lacustrine beds near Bournabat, is al- 

 ready described. In following up the ravine to the lakes of Kizghioul and 

 Karaghioul, several varieties of trachyte and tufaceous rocks occur along the 

 junction of the hippurite limestone and schist. At the lake of Kizghioul, a 

 branch from the igneous rocks extends to the eastward for some distance. 

 The Section, No. 3., Plate XXXIl., is here exposed. 



About four miles further west, immediately opposite Smyrna, (see Map) a 

 long, narrow ridge descends the side of Cordileon, and divides the waters of 

 two torrents. The composition of this ridge differs greatly from that of the 

 brown trachyte of the surrounding hills. It consists of decomposing felspar, 

 principally of a white or yellow colour, yet it presents also various shades of 

 red and brown. It has a soapy feel, and would perhaps be a valuable material 

 for pottery. At the upper end of the ridge, near a village, is a steep, broken 

 escarpment, where some dikes of bluish and reddish trachyte penetrate the 

 light-coloured substance, above described. 



The soft, decomposing state of this rock has given that smooth, rounded 

 form to the ridge which so strongly contrasts it with the rugged neighbour- 

 ing hills. Its surface is covered with rounded, erratic bowlders of brown tra- 

 chyte, probably brought down by the torrents, which now flow on each side 

 of the ridge, at a time when they occupied a higher level. 



From an inspection of hand specimens, it would not be easy to decide, whe- 

 ther this white earthy trachyte has been altered since its ejection, or whether 

 it was originally poured forth in a different state from the ordinary brown tra- 

 chyte. The latter opinion, however, is the most probable, if we consider 

 first, the complete dissimilarity between this rock and those which imme- 

 diately surround it ; and secondly, the manner in which this long ridge de- 

 scends, like a coulee, from the higher parts of Cordileon. 



These are the principal phaenomena which I noticed on the north side of 

 the Bay of Smyrna ; and it will be seen that they present a great analogy to 

 those on the south. 



The geological events to be inferred from the facts described in this paper, 

 may be summed up as follows : — 



1. An elevation of several mountains, composed of rocks of the cretaceous 

 age. 



