PROCEEDINGS 



OF 



THE GEOLOGICAL SOCIETY OF LONDON. 



1831—1832. No. 23. 



Nov. 2. — The Society assembled this evening for the Session. 



James Forbes, Esq. F.R.S.E., Edinburgh ; and the Hon. Charles 

 Harris, of Privy Gardens, were elected Fellows of this Society. 



A paper was read, " On certain younger deposits in Sicily, and on 

 the phenomena accompanying their elevation." By Dr. Turnbull 

 Christie, F.G.S., and communicated by the President. 



The observations contained in this essay were made partly during 

 a short visit to Palermo, and partly on an excursion in which the. 

 author travelled from Palermo along the northern coast as far as the 

 Castello di Tusa, crossed the central chain of mountains by way of 

 Mistretta and the Monte di Castellito Nicosia, Leonforte, and Castro- 

 Giovanni, turned eastward by way of San Filippo d'Argire to Ca- 

 tania, and then proceeded along the east coast by Lentini, Syracuse, 

 and Noto to Cape Passero, where he embarked for Malta. In this 

 route he had an opportunity of examining most of the principal stra- 

 tified formations in Sicily, and hopes to have clearly determined the 

 exact place in the geological series to which many of them must be 

 referred. 



The formations described by the author are arranged under the 

 eight following divisions : — 



1. The oldest formation which he met with is a sandstone with a 

 few subordinate beds of marl and limestone, occupying a great portion 

 of the central chain of the island, and extending along part of the 

 northern coast. Its exact age he was unable during his rapid tour to 

 determine, but it is older than the Jura or Apennine limestone. In 

 travelling along the coast eastward from Palermo, the author first 

 came on this sandstone near the river Pilato, a few miles to the west 

 of Cefalu ; and the island eastward of this point principally consists 

 of the same rock and its accompanying shales. In his route thence to 

 Mistretta he passed over the great chain of the island, which in this 

 part consists entirely of this sandstone^ and attains a very great ele- 

 vation. The mountain of Sancta Diana rises 3875 feet above the 

 level of the sea, and is overtopped by many others within sight, on 

 the loftiest of which, the Madonia, patches of snow were still visible 

 on the 8th of June. 



The dip of the sandstone strata is various ; but they are in general 

 highly inclined, and sometimes vertical. Their direction is for the 

 most part parallel to the general direction of the chain itself, — namely* 

 inclining from the north of east to the south of west. At Mistretta 

 the strata are seen distinctly to dip away from an anticlinal line, 



