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Brief Notes on the Geology of the Country round Elsdon, in 

 Northumberland. By G. A. Leboue, M.A., F.G.S., Pro- 

 fessor of Geology in the University of Durham College of 

 Physical Science, Newcastle-on-Tyne. 



Although the -writer of these notes has, at various times, spent 

 many days and even weeks in working out the detailed geologi- 

 cal structure of the neighbourhood of Elsdon, he must confess 

 that the nature of that structure was such that at his departure 

 from the district the details remained masters of the field — not 

 he of them. Concerning the larger facts of the region there is no 

 doubt left ; but the exact horizon of some of the beds, and the exact 

 nature of some of the faults which dislocate those beds — these are 

 points on which evidence is yet needed, but which we may ex- 

 pect to see satisfactorily cleared up when the Geological Survey 

 maps of the area in question come to be published. 



If we tabulate the various members of the geological series that 

 may be studied within, say, four or five miles of Elsdon, we get 

 the following column : — 



Eecent Deposits. 

 Eainwash. 

 Calc-tuff. 

 Alluvium. 

 Peat. 



Sitb-Eecent Deposits. 

 Old Peats and Alluvia, 



Drift Deposits. 

 Moor Gravels. 

 Moraine heaps. 

 Ee-assorted Boulder Clay. 

 Boulder Clay. 



Lower Carboniperous. 

 Part of the Bernician Series. 



Igneous. 

 Dolerite. 



The Rainwash, a deposit the formation of which is of the 

 highest interest, as illustrating many important processes, and 

 which is far too little studied, is common on every hill-side, and 

 daUy adds its quota of sediment to the AUuvia of the vaUey bot- 

 toms — sand, coarse and fine, from the grits and sandstones which 

 form the great mass of the fells hereabouts, clay from the shales 

 accompanying the grits, and in much smaller quantity small 



