456 ox THE ACTIOX OF LAXD-ICE AT &EEAT CEOSBT, LA5fCASHIEE. 



cilable with that view. The phenomena described in this paper 

 seem to me stronger evidence in favour of the land-ice hypothesis 

 than any I had previously seen. It seems to me next to impossible 

 that the disturbance of these shales could have been effected by 

 floating ice in any form, and the entire absence of extraneous material 

 in the " kneaded-up marls " lends further force to this view. 



It is not easy to get the exact direction of the dip of the shales ; 

 but it is from north to south or between that and north-east to 

 south-west. It follows from this that the lower beds must crop up 

 towards the north, though the country is so buried in a mantle of 

 Low-level Boulder- clay that the outcrop is not seen. If the dis- 

 turbance of the shales were due to land-ice coming from the north 

 or north-west (the nearest stride so far recorded are at Little Crosby 

 quarry, 22° W. of X., and opposite the Police Station at Great Crosby, 

 40"^ W. of J^.), the outcrop of the lower beds consisting of sandstones 

 would be torn up and pushed over and into the kneaded-up shales 

 at all angles, and this so far corresponds with the facts described. 

 Some of these rocks may have been glaciated in situ, and then 

 broken off and pushed along and into the shales. 



The tendency of the foregoing facts and phenomena is towards 

 proving that the period of greatest cold preceded the deposition of 

 the Low-level Boulder-clay. This I have already pointed out, first 

 in 1874 and in various papers since. 



DlSCTJSSIO^sT. 



The Peesidext, while admitting that Mr. Eeade's evidence seemed 

 to point to land-ice, said that it was diflScult to imagine a glacier 

 on so slight a slope as that between the Lake-country hills and 

 Liverpool. 



Mr. Whitakee insisted that the lower bed, having no erratics 

 from a distant source in it, must have been of different origin from 

 that with so many far-traveUed blocks. 



Dr. Hixde said that the absence of far-travelled erratics in the 

 till of the area described by Mr. Eeade was a local and not a general 

 characteristic of this kind of rock, since in the lake-region of 

 Canada and the United States the tiU, which is believed to have 

 been similarly formed by land-ice, contains an abundance of erratics 

 from distant localities, though it is mainly composed of the de'bris of 

 local rocks. 



The Atjthoe admitted the difficulty suggested by the President as 

 to the motion of ice from so distant a source as the Lake-district 

 over so slight a slope. He believed, however, that the mechanics of 

 land-ice remained to be explained ; but the facts he had recorded in 

 the paper seemed to him quite iiTCCon cilable with the theory that 

 the deposit was formed by floating ice either as icebergs or shore- 

 ice. In reply to Dr. Hinde, he stated that he did not think that the 

 view that the Canadian Boulder-clay was due to land-ice was by any 

 means proved to be the true one. 



