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settle the question. If this rock prove to be Cumbrian, it will be 

 the strongest proof that we can offer as to the local derivation of 

 the Boulder Clay, and should serve as another argument against 

 the iceberg theory, that assumes that our district was a grand 

 rendezvous for ancient bergs, which here melted and deposited 

 their solid contents borne from the ice-fields of the Arctic circle ; 

 though this theory has received well-nigh a death-blow from the 

 elaborate work of the Scotch Geological Survey, which has proved 

 that the boulders in the deposits in that country are derived from 

 the two great mountain districts of the north and south 

 respectively, each within their own boundaries, except in a zone 

 running across the central districts of the valleys of the Clyde and 

 Forth, where the two great glacial systems coalesced, and where 

 boulders from the north and from the south are intermingled. 



We have scarcely begun the examination of the so-called 

 Middle Drifts, deeming them perhaps the most difficult part of our 

 work, and that it would be wiser to take first the simpler branches; 

 and we find no lack of subjects, for the more we have done the more 

 we see there is to do ; or in other words — the more we have 

 learned, the more we find we do not know ; at every turn some- 

 thing fresh crops up, often leading far away into other fields of 

 science. I do not doubt but that it will be found that these drift 

 beds are, in Furness, a very difficult subject, as they are 

 frequently of wide extent and of considerable thickness; as a 

 sample may be taken, a very fine section of gravel south of Furness 

 Abbey, about forty feet high, which is slightly stratified, and 

 contains, in certain zones, large quantities of Red Hematite at a 

 much greater altitude than any known deposit of that mineral in 

 Furness ; and I may here mention that we have found Hematite 

 in several other localities several miles from the nearest known 

 deposits, and occasionally in comparatively large quantities within 

 small areas. If our Boulder Clay owed its origin to icebergs, it is 

 indeed a strange vicissitude of fortune that large numbers of 

 pebbles of a mineral so rare in quantity as Red Hematite, should 

 be brought from the frozen north, to be cast on the shores of 

 Cumberland and Furness ! 



