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XXIX. — On the Geology of the Thracian Bosphorus. 

 By HUGH EDWIN STRICKLAND, Esq., F.G.S. 



[Read November 30, 1836.] 



During a short residence at Constantinople, in March 1836, I made some 

 researches into the geology of its vicinity. A very cursory examination suf- 

 ficed to show, that the district was unexplored, and that the brief geological 

 remarks, which exist in the works of other travellers, are very unsatisfactory. 

 I therefore communicate my observations to the Society, in the hope that, 

 though slight, they may serve as a guide to those geologists who may here- 

 after be induced to explore this interesting district*. 



The formations in the neighbourhood of the Bosphorus may be classed as 

 follows : — 



1. Silurian schist and limestone. 



2. Igneous rocks. 



3. Tertiary limestone. 



4. Ancient alluvium. 



1, Silurian Schist and Limestone. 

 This formation occupies both sides of the Bosphorus for about three quar- 

 ters of its length, and extends thence towards the W.N.W. and E.S.E., to an 

 unascertained distance in Europe and Asia. It may probably form a great 

 part of the Balcan range, of which the hills above the Bosphorus are a con- 

 tinuation. 



Section west coast of the Bosphorus from the Sea of Marmora to the Euxine. 



Trachyte and Tufaccous conglomerate. 



I I 



* These observations were made in company with Mr. Hamilton; but that gentleman beinc 

 still on his travels, I have been deprived of his direct assistance in drawing up tliis paper. 



