134 



NOTES ON THE DBIFT DEPOSITS 



let us suppose a glacier filling the deep valley of the Duddon, 

 or any of the other valleys of Cumberland, and extending 

 from the mountain sides down into the sea, until part of it 

 broke off and floated away across Morecambe Bay as an ice- 

 berg, (a circumstance of common occurrence with the glaciers 

 of Spitzbergen and other northern countries,) and afterwards 

 melted or toppled over, having deposited its cargo of rocks and 

 debris on the bottom of a sea composed of soft mud. This 

 would account for most of the phenomena we witness in the 

 till. The Scotch and Irish rocks might have been brought by 

 a stray iceberg conveying specimens of stones from those more 

 remote districts. I mention this opinion, formed after a care- 

 ful consideration of the appearances observed in examining 

 the bed of stony till, but, of course, it will not account for the 

 sand and shingle beds, which are evidently nothing more than 

 old littoral deposits. The beds of clay, containing pebbles 

 Nos. 1 and 2, do not afford such strong proofs of glacial and 

 iceberg action as deposit No. 4, but still they exhibit more 

 appearances of having been deposited at the bottom of a sea 

 in which icebergs floated than under any other condition. 



The deposit No. 4 is by far the greatest in thickness, 

 although very little of it is exposed at Blackpool or North 

 Fell under the beds of silt, which I think might be termed 

 its upper boundary. 



The two anticlinal axes of the bed of silt lead me to suppose 

 that the deposits Nos. 1 and 2 lie in a synclinal axis of it, 

 which extends from near the Gynn to North Fell. The dip 

 of the beds of gravel may scarcely bear out this view, but that 

 is by no means so great as appears in the section, as I previ- 

 ously stated ; in fact, in some places it takes a northerly dip, 

 and at others is so small as scarcely to be appreciated ; so I 

 have little doubt of the beds of silt and stony till underlying 

 the whole of the gravel between the two last named places. 

 It appears to me the till was once an old sea bottom. Upon 

 its being elevated, it would soon be exposed to the action of 



