1865.] GODWIN-AUSTEN POKLOCK FOEEST-BEDS. 7 



great masses or " trainees " of the debris have come down from 

 above, cutting deep channels through the detritus at lower levels. 



These accumulations of angular detritus along the lower slopes are 

 of great thickness ; the materials have also been carried forward to 

 considerable distances, more particularly in advance of deep glens. 

 The high ground from Countesbury to Dunkerry (1678) and Porlock 

 Hill has everywhere good illustrations of the character of these 

 masses of detritus. 



A section of such beds is to be seen in a low cliff extending east- 

 wards from Porlock Quarry, and serves to connect the detrital mate- 

 rials of the interior of the country with the beds beneath the bay. 

 It is a section of part of the under- terrace already noticed. 



This section, which has a depth of from 10 to 12 feet above the level 

 of the shingle, shows an accumulation of earthy materials, angular 

 fragments of all sizes, all derived from the rocks of Porlock HiU. 

 There is to be noticed a sort of horizontal arrangement resulting 

 from interbedded lines of finer materials, and showing successive 

 accumulation. On either side of the place at which a stream comes 

 down to the coast, cutting through the thickness of angular mate- 

 rials, there are to be seen, mixed with it, some water- worn, partially 

 rounded blocks ; these indicate the course of a torrential stream from 

 the high grounds above (as at present), but occasionally of greater 

 volume. 



This accumulation of angular materials is referable to like bygone 

 conditions as have been already indicated for the whole of the rest 

 of the West of England (Quart. Journ.Geol. Soc.vol. vii.pp. 121-131). 

 It is a condition of surface presented everywhere by that portion 

 of this country, and of Europe, which was not submerged during 

 the great subaqueous depression of the Northern hemisphere. In 

 geological history it belongs to the subaerial phenomena of the 

 " Glacial Period," and represents the whole of the variable conditions 

 of that long interval of time. 



III. Conclusion. 



Eeversing the order of superposition, the sequence of change at 

 this place is as follows : — 



1st. The formation of angular detritus, and its accumulation at 



lower levels. — Highest relative level. 

 2nd. Eorest-growths established on detrital beds. — Trees of 

 I great age. 



T 3rd. Accumulation of freshwater mud, resulting probably from 



ta depression of the level of the land. — Trees killed. 

 4th. Surface of water-plant growths on mud- deposit, or nearly 

 dry surface, on which the trees fell. 

 1 5th. Deposit of sea-mud, with JScrohicularia. — Area depressed 

 below the sea-level. 

 6th. Conversion into meadow, at the level of the highest springs 



at present. 

 7th. Shingle. 



