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is to break off and wear down all the prominent angles, so that the 

 stones gradually assume more and more of a rounded form, just as 

 we see them in the bed of the Eden below us. Beds of stones 

 rounded in that way form what we call gravel when the stones lie 

 uncorapacted, and conglomerate when they are all bound together 

 into a compact mass. If the fragments are not rounded, then the 

 compacted rock formed of such material is distinguished as a 

 breccia. The coarse beds occurring in the Penrith Sandstone are 

 largely — often exclusively — made up of such angular fragments, 

 which form the rock locally denominated Brockram. The stones 

 in these breccias are mixed together without any regard to either 

 their shape or their size. In a bed consisting of fragments having 

 a general size of, say, a walnut, stones as big as one's head or 

 bigger are not at all uncommon ; and these stones are all frequently 

 quite angular. Now these beds of Brockram are well stratified 

 and are interbedded with sheets of fine-grained sandstone; so when 

 we find stones of all sizes up to two feet in diameter scattered 

 indiscriminately throughout both the breccias and the fine sand- 

 stone, we may venture to feel tolerably certain that they have not 

 got into their present position in the ordinary way. Floating trees 

 often transport big stones many miles entangled in their roots, but 

 there seems to have been no floating trees at that time, in this part 

 at least ; and besides, these stones are far too numerous to be 

 accounted for in so exceptional a way. There is a considerable 

 resemblance between these beds of breccia and many parts of our 

 well-known glacial drift, and if it had not been that the stones in 

 the breccias are all arranged with their longer axes parallel to the 

 bedding planes — if they did not all lie on their flat sides — and if 

 the rock as a whole had not been most clearly stratified throughout, 

 they would have been at once set down as old glacial deposits. 

 Indeed, they have been more than once referred to a glacial origin 

 by those who have not been fully aware of the facts I have 

 mentioned. That ice has had to do with their anomalous character 

 I have no doubt, but this ice must have been in the form of coast 

 ice, like the Ice-foot of the Arctic regions. As the land sank down 

 and various portions of the sloping shores were successively brought 



