334 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 28, 



2. Notes on the Geological Structure of parts of ^it^j)^. By Capt. 

 N. ViCARY of the Hon. East India Company's Service, in a letter 

 addressed to Sir R. I. Murchison, G.C.St.S., F.G.S., F.R.S., 

 and communicated by him to the Geological Society. 



Sir, — The following geological notes were written during an ex- 

 cursion from Kurrachee to Sukkur in November and part of December 

 1845, and as so little is known with respect to the geology of Sinde, 

 I trust that even these rude notes may not prove unacceptable. 



The station of Kurrachee, lat. 24° 53', long. ^7° 17', is situated 

 upon a coarse-grained, dirty yellowish, arenaceous rock, held together 

 by a calcareous cement. In some places this rock is loose-grained 

 and easily worked, in others hard and containing sufficient calcareous 

 matter to afford an impure lime. In all places it contains fossils in 

 abundance. This rock, although conformable, lies higher in the 

 series and is more recent than that which composes the elevated parts 

 of the Hala range of mountains. It is in many places directly over- 

 laid by a calcareously cemented conglomerate, in other places a sand- 

 stone of some thickness intervenes. This sandstone is usually desti- 

 tute of fossils, but near Kurrachee some of its thin beds, varying from 

 1 inch to 2 or 3 feet in thickness, are composed almost exclusively of 

 fossil shells. 



The pebbles forming the conglomerate are all rounded, and for the 

 most part derived from the nummulitic limestone of the Hala range, 

 and I found some broken remains of oysters and Cerithia in the rock. 

 A conglomerate retaining the same character is found flanking the 

 eastern face of the Hala Range, from Cape Monze to the west of 

 Mittun-Kot. In some places it attains sufficient elevation to con- 

 stitute a distinct and well-defined range, and is often of vast thickness. 

 We are still in want of information as to its extent in a northerly 

 direction along the base of the Sulleemaun Range. 



The neighbourhood of Kurrachee is characterized by low hills, not 

 exceeding 200 feet in height. In many places they appear like islands 

 in a shallow sea, and a subsidence of 150 feet would make them so ; 

 in other places they form a continuous narrow range for two or three 

 miles. They are often capped with the conglomerate, disintegrated at 

 the surface, but still cemented beneath. The low intervening valleys 

 and plains are composed of the same coarse arenaceous rock on which 

 Kurrachee stands. It is evident that the conglomerate, sandstones, 

 &c. have there been removed by the action of water ; by tidal action 

 perhaps, while the whole country was submerged. About three 

 miles east of the station there is a low range of hills running nearly 

 parallel with the sea-coast, from which they are now distant between 

 four and five miles. The rock is a fine-grained sandstone without 

 fossils, in some places capped with conglomerate, in other places that 

 rock has been swept away. The western face of this sandstone forms 

 an abrupt cliff, and undoubtedly has at some period been subjected to 

 the ebb and flow of the sea. The cliff is everywhere eroded by the 

 action of the waves, and is in many places pierced by saxicavous 

 mollusks. About a mile to the southward of these hills, and three miles 



