18GS.] MACKINTOSH BRISTOL Cn.VNNEL. 281 



up in strange confusion. Under the lofty cliffs there is, generally- 

 speaking, a block-beach — further seaward, shingle and sand, often 

 alternating along-shore — then rocks more or less covered with clay 

 or silt, succeeded by ridges of bare rocks, like natural breakwaters, 

 which extend seaward to a great distance. The bed of the sea, 

 here, is far from being level, though the inequalities, it is true, are 

 on a small scale. At intervals along-shore there are miniature bays, 

 which are concealed at high water. Indeed the configuration of 

 the sea-bed under and for some distance from the cliffs very much 

 resembles the uneven ground at the base of many inland escarpments. 

 Beyond Blue Anchor, the old forest-ground rises out of the sea, 

 passes under a ridge of shingle, and runs along the adjacent valley. 



5. Raised Sea-bed. — Immediately to the east of Watchet a greater 

 or less thickness of gravel may be found filling up hollows in the 

 Infralias(?). It consists of well-rounded pebbles of quartz. Old Red 

 sandstone, Devonian slate, &c. Further eastwards, in Doniford Bay, 

 it attains a thickness of at least 20 feet, with a covering of about 

 4 feet of loam. Its surface there inclines in an easterly direction 

 until it passes under the sea-level. Landward it extends along the 

 valley leading to Williton, or thins out against the slopes of the hills. 

 Near Watchet it rises to a level above the sea of at least 50 feet. 

 Is it of the same age as the shingle of the so-called raised beaches ? 



6. Encroachments near Weston-snper-Mare. — The sea is converting 

 slopes into cliffs, where it is not silting up flat areas*, from Brean 

 Down to a considerable distance northwards. Both sides of Brean 

 Down (the outcrop side and dip side) bear witness to its action. 

 On the latter the appearance of a terrace about 30 feet above high- 

 water-mark strikes the eye at a distance. It has been regarded as 

 a " raised beach "; but I am not aware that it has ever been particu- 

 larly examined. Near Weston, the sea is forming a line of cliff on 

 the north-western side of Weorle Hill, which runs nearly parallel 

 to what appears to be an old line of sea- cliff near the top of the hill. 

 At Birnbeck Cove its encroachments have disclosed, or rather nearly 

 destroyed, the last remnants of a genuine raised beach, which, as it 

 may soon be no more, deserves a brief description. I found it repre- 

 sented at intervals along the top of the cliffs from the Flagstaff, as 

 far as the bathing-cove, by small rounded flints, angular flints like 

 chips or flakes, angular fragments of limestone, and loam, in places 

 covered with a thin layer of rounded stones — the whole associated 

 with land- and sea- shells (Littorina and Tellina). The raised 

 beach assumes its most decided character in Birnbeck Cove — a small 

 recess, which in stormy weather is one day choked up with blocks 

 and shingle, and the next cleared out by the sea. A brief description 

 of the raised beach has been given by Mr. Day in the ' Geological 

 Magazine ' (March, 1866), with a theoretical transverse section. I 

 subjoin a front view in Fig. 2. It rests on the upturned and denuded 



* As a general rule, where conditions are favourable to both processes, the 

 sea silts up valleys and denudes hills. Alternately, along-shore, it acts as a pre- 

 server and destroyer of land surfaces. This fact, I think, ought to be borne in 

 mind in speculating on the action of the sea during the glacial submergence. 



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