130 



NOTES ON THE DRIFT DEPOSITS 



resting fact is, the quantity of both granular and fibrous 

 gypsum and waterstone from the upper red marls of the trias. 

 These I have seldom found previously in the till of Lanca- 

 shire. But the greatest novelties, in the shape of rocks, are 

 two specimens of lias, containing the gryphaea incurva and 

 pieces of chalk flint. These I have never yet found in Lan- 

 cashire, except at Blackpool, nor have I ever heard of their 

 having been noticed by other parties. 



The shells met with in this deposit are, on the whole, much 

 more numerous than those found in Nos. 1 and 2, but they 

 are nearly all more or less broken. I have found specimens 

 of the genera turritella, nassa, buccinum, dentalium, nucula, 

 cardium, tellina, and psammobia, most of which had been 

 previously found by my friend, Mr. Robert Harkness, in the 

 till, near Ormskirk. 



The sea appears to be encroaching on the cliff composed of 

 till, where it is not protected, at the rate of about one yard 

 every year on the average. At places where the sand and 

 gravel beds occur, its attacks are more rapid. This destruc- 

 tion of the land seems to have gone on for centuries, as the 

 low water mark, at spring tides, shows numerous large blocks 

 of stone, evidently derived from the till and gravel, when the 

 boundary of the cliff was nearly at that point. Some of the 

 pieces of cemented gravel, like the Pennystone, are of im- 

 mense size. 



During the last year, the beds of sand and fine gravel (No. 2) 

 in the cliff between the Royal Edward and Dickson's Hotel, 

 have been exposed far more than they had been previously 

 supposed to exist in that neighbourhood ; and if the sea is 

 allowed to continue its attacks, without any attempt being 

 made to resist it, the destruction of land will, most probably, 

 be much greater than at the rate at which it has been destroyed 

 during the last ten years. 



As previously stated, the deposit. No. 2, in Bispham, bears 

 every resemblance to an old beach of shingle, like those at 



