Edward Merrick — The River Tyne Drainage Area. 359 



increase of coastal land ; the greater the amount of land and elevation 

 the greater the probability that the streams now running into the sea 

 would run into the continuation of the Tyne over the extra country. 

 This would cause the present watersheds to be deflected so as to 

 include these drainage areas, but these deflections could only affect 

 the south and north watersheds. The west one would remain 

 unaltered from this cause. 



It may be mentioned here that several authorities believe that the 

 western watershed has been altered by tributaries from the Eden 

 capturing the Irthing. The western watershed, through being part 

 of a long one, has a feature shared by many other rivers. This long 

 watershed separates the streams flowing into the North Sea from those 

 to the Atlantic, Irish Sea, and English Channel. The continuation 

 of this watershed in Europe separates the rivers flowing to the North 

 Sea from those to the Mediterranean Sea, and ultimately joins the 

 watershed between the Atlantic and Pacific Oceans. A geological 

 feature of this watershed is that from the North to the South of 

 England it lies upon rocks becoming younger and younger, as also do 

 the strata on the coast, the result being that the more south a drainage 

 area is, the younger it appears from the deposits contained in it. 



Fig. 10. — Soundings (diagrammatic) off the Mouth of the Tees following the 

 sea-level (0 feet) contour of the peneplains from Cross Fell (Palaeozoic 

 rocks) and the Cleveland Hills (Mesozoic rocks). 



The continental continuation of this watershed enters the Alpine 

 region, which was a centre of great mechanical energy. Is it an 

 allowable inference that movements contemporary with the formation 

 of the Alps would follow older lines of weakness to an increasing degree 

 as the distance from this centre of activity increased, and ultimately 

 with complete coincidence, where young deposits are absent, that the 

 age of these movements would consequently be dated further back? 



At the present time the Tyne area can.be considered as part of 

 a larger unit which includes all rivers receiving tributaries from Cross 

 Fell or which act as tributaries to them. This unit resolves itself into 

 the Eden and its tributaries on the west, and the Tees, "Wear, and 

 Tyne on the east. To these the Blyth, Wansbeck, and Coquet might 

 be added. 



The southern watershed to this system runs from the Lake District 

 to the Cleveland Hills, and is generally associated with anticlines. 



