Geological Society of London. 325 



Prof. M'Coy. The surface-rock in the neighbourhood of Cape York 

 is an ironstone, varying from a light friable clay to a dense ferru- 

 ginous conglomerate, sometimes nodular and magnetic ; an average 

 specimen contained 39'69 per cent, of iron. This deposit extends 

 at least as far south as the Mitchell Eiver, on the west side of the 

 peninsula, and as far as Weymouth Bay on its east side. It is re- 

 garded as Post Tertiary by Mr. Clarke. Between this and the igneous 

 rock intervenes a local deposit of coarse quartzose sandstone, which 

 forms bold cliffs in Albany Island and on the opposite coast of the 

 mainland. No boulder-deposits or glacial markings were detected 

 by the author. 



The author referred to the occasional occurrence of earthquakes 

 in Eastern Australia, and to the evidence that at least the North- 

 East of that continent is being slowly elevated, namely, the occur- 

 rence of water- worn caves above high-water mark in Albany Island 

 and on the opposite coast, the existence of extensive plains covered 

 with sand-dunes, especially towards the north of the peninsula, and 

 the gradual emergence of islands in the line of the great Barrier 

 Eeef. 



2. '■ On the Formation of the Chesil Bank, Dorset." By H. W. 

 Bristow, Esq., F.E.S., F.G.S., and Wm. Whitaker, Esq., B.A., F.G.S. 



The authors first described the general character of the bank, and 

 noticed the previous hypotheses that have been suggested to account 

 for its formation. They maintained that it had been formed as an 

 ordinary shingle-beach banked up against the land, and afterwards 

 separated by the wearing action of the small rivers flowing to the 

 sea at this part. They stated that west of the Chesil Bank there 

 are cliffs of greater or less elevation, through which small streams 

 flow down to the shore, when they turn a little eastward between 

 the beach and the land, and then filter through the shingle without 

 breaching it. The effect of a similar river-action on the low shore 

 behind the Chesil Bank would, in the authors' opinion, be to cut 

 such a channel as that of the Fleet, by which this bank is separated 

 from the shore. 



Discussion. — Mr. Evans suggested that tidal action may have assisted materially 

 in the formation and widening of the Fleet, which may have originated in a breach 

 between Portland Island and the mainland. 



Mr. W. Boyd Dawkins instanced a case at Pagham Harbour, where a bank of 

 shingle was advancing and diverting the course of a stream to the East. He also 

 instanced the shingle-beach at Shoreham, and argued in favour of the marine origin 

 of the channel. 



Mr. Flower inquired as to the rocks fi-om which the pebbles had been derived, 

 and suggested that the examination of this deposit might throw light on the origin 

 of such formations as the Wool'nach and Reading Beds. 



The President observed on the similarity of the operation of the sea on such beaches 

 to that of winds on sand-dunes, which travel forward diuing high winds and storms, 

 and inquired why the beach still continued so straight without trending to the north 

 when no longer supported by the land, and to the east of Abbotsbury. 



Mr. Whitaker did not regard the cases at Pagham and Shoreham as analogous with 

 that of the Chesil Bank, inasmuch as the point of the shingle-banks did not touch 

 the land like the Chesil Bank, which rests on high land at Portland. The pebbles 

 were of all rocks, and derived from the westward. There were no data by which to 

 judge of the travelling landwards of the beach, M-hich was, however, far from straight. 



