20 



clay and the subjacent Hastings' sands, is not well defined in the 

 tract which the author describes. A considerable bed of sand oc- 

 curs within the clay at its upper part ; after this comes in a bed of 

 Sussex marble ; and, lower down in the clay, a second layer of 

 sand containing siliceous grit in thin beds, — beneath which, the prin- 

 cipal beds of Sussex marble (about 18 inches in thickness) occur; 

 and these are finally succeeded by blue, brown, and red clay, and 

 micaceous sand, the commencement of the forest ridge. 



The author gives a particular description of the defile of the 

 Arun, the principal outlet of the Weald in the south of Sussex. 

 This river traverses about 15 miles of a country almost mountain- 

 ous, cutting across the ridges of the sand and the chalk escarp- 

 ment nearly at right angles to the valley of the Weald. The gorge, 

 where it enters the green sandstone, is more than 400 or 500 

 yards in width at the bottom ; the banks rise quickly to the 

 height of about 200 feet on the east, and on the west to about 400 

 or 500 feet. At Bury and Amberly, where the river penetrates the 

 chalk, the hills are 600 or 700 feet high ; the ravine having all the 

 characters of a fissure. And, as the strata, in several cases of this 

 description, rise on both sides towards the crack, the author sup- 

 poses that the channels now existing on the surface, have been 

 produced by the operation of some internal forces by which the beds 

 were broken up and elevated ; and that the drainage of the country 

 by the present outlets, can be thus explained, without having re- 

 course to a debacle, or to denuding operations : and he supports 

 this hypothesis by reference to the local features of the country, 

 illustrated by sections. 



April. 6. — William Carpenter Row, Esq. of Baliol College, Ox- 

 ford ; W. A. Mackinnon, Esq. of Hyde Park Place, London ; John 

 Lindley, Esq. of Chiswick, F.L.S. ; Neil Malcolm, Jun. Esq. M.P. of 

 Duntroun Castle, Ayrshire ; and The Rev. J. Mc Enery, of Torquay, 

 Devon, — were elected Fellows of the Society. 



M. C. Von Oeynhausen, of Berlin ; and M. C. Von Dechen, of 

 Berlin, — were elected Foreign Members of the Society. 



The reading of a paper " On the magnesian limestone of the 

 northern counties;" by the Rev. Adam Sedgwick, Woodwardian 

 Professor in the University of Cambridge, was begun. 



