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glacial epoch, matters to that extent would be much simplified, 

 and it may be wise in our explorations if we ask ourselves whether 

 the observations we may make will not fit in with the more simple, 

 as well as with the most complex theories. Doubtless these so- 

 called Middle Drifts are most difficult of explanation, so much the 

 more must we patiently examine them, and not be too ready to 

 draw rash conclusions. They have already given rise to innume- 

 rable discussions and disputations, whilst the most opposite theories 

 have been derived from them. In Ireland some members of the 

 Geological Survey think that the Boulder Clay in that country may be 

 divided in such a manner that it may only be necessary to assume 

 one glacial epoch, which was succeeded by warmer conditions, 

 with the sea at higher levels, and that this period was that to which 

 we must attribute the so-called Middle Drifts, whilst in addition 

 there is much moraine matter due to local glaciers from the high 

 ground. If the results of years of study in Ireland have led to 

 these conclusions, may we not hope that the same may be the 

 case later on in England, especially when we remember that the 

 author of the Geological Survey memoir for the south of our own 

 district acknowledges the extreme difficulty of determining over 

 large areas whether the so-called upper deposits are Upper or 

 Lower Boulder Clay. Doubtless in Furness there is the appear- 

 ance of sand and gravel beds separating the Boulder Clay into 

 two great divisions, but no palseontological evidence has yet been 

 adduced in support, and it may be that as in Ireland we may have 

 a threefold division, and that in our district what has been taken 

 to be the Upper Clay may partly be of moraine origin, and partly, 

 with the underlying gravels and sands, may be the work of the sea, 

 re arranging the old boulder clay beneath, tliough this suggestion 

 would be difficult to reconcile with our present knowledge. There 

 is here room for much study, and I believe that there are not a 

 few students who are ready to work on the subject, and we must 

 hope that the result will be that within a few years the tangled 

 history of this portion of the past will be unravelled, when we 

 shall see the true bearing of these disputed beds. Clearly 

 there is much to learn, when even the origin of the deposit is 



