GEOLOGY 



stone pounder, charcoal, cockle and periwinkle shells. The position of 

 the kitchen midden needs verification. 



T. M. Hall,* in 1864, recorded the exposure at Westward Ho of 4 

 feet of peat with trunks of between seventy and eighty large trees, appar- 

 ently oak, birch and hazel, hazel nuts, flint flakes, bones of deer, ox, wild 

 boar, wolf, etc. He found decomposed pointed stakes driven in a rude 

 semicircle into a quantity of small perfectly angular stones which, in 

 places, were observed under the peat. 



In south Devon. — In Bigbury Bay, close to the north end of the 

 Thurlestone Rock reefs, Pengelly" records the exposure of dark blue clay 

 with trunks of trees, including oak, at 150 feet seaward of high water 

 mark. 



At North Sands, in the Salcombe estuary, peat with remains of trees, 

 including oak, is sometimes disclosed by gales. 



At Blackpool near Stoke Fleming brown clay with twigs, nuts, 

 leaves, tree trunks and rooted stumps, and bluish clays on the land- 

 ward side, were exposed in 1869.^ In 188 1 the forest traces were 

 again visible.* 



On Tor Abbey Sands 10 feet of peat with trees has been seen, 

 also on the foreshore at Paignton where the blue clay associated with 

 the forest bed is often visible. In this Torbay Forest, at Tor Abbey 

 Sands, Goodrington and Broad Sands, bones of red deer, wild boar, 

 horse, long-fronted ox and mammoth are said to have been found." 

 The peat passes under the alluvial clay of the Paignton and Goodrington 

 marshes. Signs of submerged vegetation have been observed at Sid- 

 mouth. The extensive peat bogs on Dartmoor may be included in the 

 same period of arboreal extension. 



The slower rate of denudation during the later stages of the sub- 

 sidence, which led to the advance of the sea to its present bounds and to 

 the final submergence of the lower forest areas, is exemplified by the 

 narrow waterways of the present streams and rivers excavated in their 

 older and broader beds, by the silting up of estuaries and the formation 

 of sandbanks like the Warren, or of gravel beaches as in, the case of the 

 Otter, Sid, and lesser streams across their mouths. 



During this movement of subsidence oscillations seem to have taken 

 place, and to this cause the occurrence of recent estuarine conditions in 

 sites no longer aff^ected by them, as in the case of the Alphington gravels, 

 has been ascribed by Godwin-Austen. How far such oscillations may 

 have contributed to the formation of such gravel beaches as Slapton 

 Sands, and the Northam Pebble Ridge, is open to conjecture. 



Caverns. — The bone caves and fissures of Devon are naturally con- 

 fined to the limestone areas of Plymouth, Yealmpton and Torquay. 



* Hall, Proc. Soc. yintiq. for I Dec. 1864. 



* 'On a Newly Discovered Submerged Forest, etc' Trans. Devon Assoc, for 1866. 

 ^ Pengelly, Trans. Devon Assoc, for 1869. 



* Hunt, ' On Exposures, etc' Trans. Devon Assoc, for 1881. 



' Pengelly, 'The Submerged Forests of Torbay,' Trans. Devon Assoc, for 186;. 



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