64 C. E. De Ranee — Mineral Veins i?i the North-ivest Country. 



denudation, and sucli too would be the case, as Mr. Wilson suggests, 

 "where the beds presented their upturned edges to the moving ice. 



The vast numbers of well-rounded and scratched stones that occur 

 in the Drift, and of which it is in fact in many cases mainly composed, 

 have alwaj^s been a great difficulty. Much has been written of late 

 years about the moraine profonde, as such masses of Drift are now 

 called : but no attempt has been made, that I am aware of, to explain 

 in a definite manner the origin of such heaps of scratched gravel ; it 

 seems to have been thought sufficient to call them moraine profonde. 

 This term, when originally used in Switzerland, was employed, as I 

 am informed by one who is an authority on the subject, to describe 

 the case of an advancing glacier overriding its own terminal moraine. 

 In such a case no doubt the glacier might so grow as to shove its 

 terminal moraine along in front of and partially beneath it : and the 

 matter of the moraine would be greatly altered in nature and 

 arrangement. 



Doubtless also at the commencement of the Glacial epoch the 

 ice as it advanced would sweep before it all the loose detritus from 

 the hill-sides and beds of river-gravel or old sea-beaches; and in 

 this progress the stones would get scratched and further rounded. 

 But all such heaps of detritus must have been long since swept 

 away from the hills and deposited mostly at the outskirts of the ice- 

 sheet ; and must now be sought perhaps in the vale of York. We 

 must seek another way to account for the masses of scratched gravel 

 and Boulder-clay found in the very heart of the fells. When these 

 were formed and deposited, the country must have been entirely 

 buried in ice, as Greenland now is. There could, therefore, have 

 been no cliffs sticking through the ice to afford boulders for the 

 Drift ; we are thus driven to suppose that such boulders were 

 derived from beneath the ice: and I see no means by which this 

 could have been effected save by the disintegrating power of frost, 

 aided in cases by a happy disposition of the chief divisional planes. 

 But however difficult to account for, and however hard to conceive, 

 I repeat the fact is certain that there has been an enormous amount 

 of rock disintegrated sub-glacially, so as to form gravel and coarse 

 stony detritus over and above the grinding of the rocks superficially 

 into fine powder or mud. 



Y. — On the Occurkence of Lead, Zinc, and Iron Ores, in some 

 EooKs of Carboniferoits Age in the North-west of England. 

 By Charles E. De Range, F.G.S. 

 PART I. 



IN former papers I have described central Lancashire as capable 

 of division into three plains of different elevations. The lowest 

 being often beneath high-water mark, and always below the 25-foot 

 Ordnance contour ; the second ranging from 25 and 50 feet to 600 feet 

 above the sea, terminating at the foot of the steep escarpment at the 

 western edge of the Lancashire and Yorkshire moorlands forming 

 the Pendle portion of the Pennine chain, with an average eleva- 



