428 DERWENTHAUGH LAND IN DERWENT GUT. 



bed thins out towards the present Derwent mouth from 

 6-ft. 9-in. to i-ft. 9-in., and towards the Tyne from 6-ft. 9-in. 

 to 4-ft. 6-in. at No. 9 hole, whilst it is entirely removed from 

 Nos. I and 5. 



The yellow clay and soil, whose average depth is 5-ft. 2-in., 

 of course belongs to recent times, and brings us up to date. ' 



There is a good deal of prose in life, and still more perhaps 

 in science, but here we have some of its poetry. Here, with 

 the help of imagination, are a few layers of mud, and sand, 

 and gravel, and peat, telling us a story of changes in the far 

 past, that one might have thought had hopelessly receded out 

 of human ken. Telling us that the Derwent flowed into the 

 Tyne once upon a time, in the long ago, when the North Sea 

 was perhaps unknown ; when the Tyne itself was the tributary 

 of a greater Rhine; when our two counties of Northumberland 

 and Durham raised their heads hundreds of feet nearer the 

 sky than they do to-day ; and when the seasons were so 

 different that life could scarce exist, for ice and snow reigned 

 supreme, filling the lower valleys and wrapping the inter- 

 vening plains in a cloak of glacial ice slowly making its way 

 down the eastern slope like an irresistible plough, pushing 

 before it all the earth's soft coverings, and laying the bones of 

 the land bare. Further the cold grew in intensity and the ice 

 in power, till deep furrows were ploughed in the bottoms of 

 the valleys, in this case at least 144 feet below sea-level. 

 How then a change came slowly and intermittently on ; the 

 furrows grew no deeper, and were channels now for ice, now 

 for water ; life came back, animal and vegetable, and con- 

 ditions were once again as in the good old times, when water 

 always flowed. 



But meanwhile another mighty power had begun to make 

 itself felt. The surface had begun gradually to fall and fall 

 slowly but continuously inch by inch, century by century, till 

 the old smooth floor was hidden under an ever-growing 

 accumulation of mud, sand, and gravel, brought down by 

 rain and storm from the upper reaches of the river, and 

 simultaneously the sea invaded the plains of the North Sea, 



