DERWENTHAUGH LAND IN DERWENT GUT. 



427 



A close examination thus reveals the fact that these 

 changes of surface level and of climatal conditions were not 

 quite continuous, for much of the several deposits that were 

 made were afterwards removed before the next deposit began. 

 The times of deposition were separated by times of denuda- 

 tion, so that denudation has its say in the story as well as 

 deposition, and the inevitable conclusion is forced on us that 

 the general sinking of the surface was broken by stationary 

 periods. Such stationary periods have produced the irregu- 

 larity which marks the upper face of the boulder clay, whose 

 base or lower face is of wonderfully uniform slope, as the 

 following figures show. And the same holds good for the 

 hard gravel and sand, and also for the peat-bed. 









Boulder Clay. 







Western Group, 

 fths ft. ins. 



Middle Group, 

 fths. ft. ins. 



Eastern Group. 

 fths. ft. ins. 



24 



5 



6 



22 4 



19 



4 6 



20 



4 



8 



22 10 



18 



4 



19 



I 



3 



213 



21 







19 



2 







19 4 6 

 Hard Gravel and Sand. 



19 



I 



Westei 

 fths. 



rn Group. 

 ft. ins. 



Middle Group, 

 fths. ft. ins. 



Eastern Group, 

 fths. ft. ins. 



7 



3 



4 



7 5 



8 



2 4 



7 



4 



8 



7 3 9 



8 



2 



7 



3 







7 3 4 



8 



I 



7 



2 



II 



7 I 5 



8 



4 



Observe the decline in the slope as the Gut is filling up ; in 

 the boulder clay the fall is measured by fathoms, in the later 

 time of the gravel and sand scarcely by feet. 



The upper soft clay, with its yellow and brown clays, its 

 river mud and loamy sand, and especially its loamy and 

 mossy peat, belongs to comparatively recent times, and to 

 conditions not much dissimilar to those now existing. Yet 

 those times, even for the peat-bed, are most likely pre-historic, 

 for that deposit suffered considerable denudation before the 

 yellow clay, which overlies it, was dropped down, and con- 

 siderable and uniform denudation demands time. The Peat 



