538 NOTES ox THE PHYSICAL CONDITIONS EXISTING 



the peculiar formation of the famous Chesil Beach. As is well known, 

 this beach begins near Bridport with fine sand and extends a distance 

 of sixteen miles towards Portland, the sand gradually changing to 

 gravel and pebbles and thence to stones. The grading is so nice that 

 fishermen are said to be able to tell where they are, even in the dark, 

 by merely examining the materials of the beach. According to Cornish, 

 the east-going current of nine hours' duration is able to carry along 

 materials to a greater distance than the west-going current of only 

 three hours. Consequently the heavy stones are steadily being carried 

 to the eastward, until they are trapped by the projecting " island " of 

 Portland, which acts as a natural groyne. The lighter materials 

 remain longer in suspension and are carried onwards beyond the Bill 

 to the Shambles. The west-going stream may carry the suspended 

 sand backwards towards Bridport, but on the whole the drift is 

 easterly. * 



It has been mentioned that a returning eddy makes its appearance 

 in Start Bay after high water by the shore, and though this eddy has 

 not been definitely traced farther back than Berry Head, there are 

 indications of its presence even in Teignmouth Bay. In the centre 

 of the latter bay the tides are scarcely felt, and the trend of the 

 currents on the shore is in opposite directions at Teignmouth and 

 Exmouth. The former seems to be due to the returning eddy, which, 

 though weak, tends to deaden the flood-tide, whilst the latter is due 

 in part to the conjoined currents setting directly on to the shore. At 

 the lower end of the bay we have clearer evidence of the eddy in the 

 strong current which rushes through between the Orestone and the 

 mainland on the ebb, and in the accumulation of material from Teign- 

 mouth Bay on the Torbay side of the Orestone.f In Torbay itself the 

 only evidence I have found for the presence of the eddy is that the 

 trend of objects from the Brixham side of the bay is past the break- 

 water and on to Berry Head. Off Berry Head we have the deep, 

 though narrow, channel close in to land, which seems unmistakable 

 evidence of a strong eddy, and over Mudstone Ledge the eddy definitely 

 makes it appearance. Off Downend, again, we find a sandbank separated 

 from the land by a deeper channel, which has probably been formed by 

 the conflict of the flood-tide flowing easterly on the outside with the 

 eddy going to the west on the inside. Lastly, the whole appearance of 

 Start Bay is evidence of the presence and great influence of the eddy. 



On the chart it will be noticed that the depth contour lines in Start 



* According to Wheeler {loc. cit.) there is also a distinct northerly current flowing 

 along the island, and this accounts for the greater accumulation of material at Chesilton, 

 which lies at the bend where the island begins to separate from Chesil Beach. 



t See foot-note, p. 533. 



