12 



ON THE RED CHALK OF ENGLAND. 



also taken some account of its neighbours. We have noticed, too, 

 that in Yorkshire it for the most part reposes on the Speeton clay, 

 though in certain localities it is next the lias and Kimmeridge clay, 

 and that in Lincolnshire and Norfolk it rests on a dark brown pebbly 

 mass supposed to belong to the lower greensand formation of the south 

 of England. 



The Eed Chalk has also been discovered in a very unexpected place, 

 although not in situ. I allude to the drift of Muswell Hill. In that 

 collection of different materials, comprising examples from every for- 

 mation from the London clay to the mountain limestone in a stratum 

 of eighteen feet, the Red Chalk has been seen in a bouldered condition. 



By the kindness of Mr. Wetherell of Highgate, I am euabled to 

 exhibit specimens from the drift of Muswell Hill. Any person who 

 compares them with others from Hunstanton, would declare they 

 came from the same bed, so alike are they in appearance. 



There was a time no doubt when this Red Chalk had a more 

 extended range : its presence in the drift of Muswell Hill, as well as in 

 the drift of other places, implies as much. Perhaps it may still exist 

 elsewhere, deep down in the earth. 



In a well sunk at Stowmarket a red substance was found under the 

 White Chalk, at a depth of 900 feet ; and in another well sunk at 

 Kentish Town, the workmen met, at a depth of 1,113 feet below the 

 surface, beneath the gault, a bed of red matter 188 feet thick — some 

 of this red matter appeared to contain belemnites. 



Geologists are divided in opinion with respect to this deep-sunk 

 red bed, which certainly is not always continuous (for instance, it was 

 not found at a boring at Harwich), and some incline to the opinion 

 that it belongs to the New Red, others that it is the equivalent of 

 what is styled the Red Chalk. But it is difficult to give a solution at 

 present. It is certain that in the gault formation, or near it, beds of 

 a red colour are occasionally found. Near Dorking the lower green- 

 sand is capped by a local bed of bright red clay, eight feet 

 thick. And examples of red clays from the gault of Ringmer in 

 Sussex and Charing in Kent can be seen in the Museum of the 

 Geological Society of London. Whether they have any relation with 

 the Red Chalk proper of England depends upon the position which is 

 given to that formation. 



