A HISTORY OF DEVONSHIRE 



A minor feature forming an escarpment on Westdown Hill near 

 Budleigh Salterton runs northward to Talaton, attaining a height of over 

 580 feet on Woodbury Common. Apart from these elevations the 

 features of the eastern area are low and tame in comparison to those of 

 the western, except near the border where the newer sediments mantle the 

 slopes and cap the summits of the older rocks, attaining heights of from 

 700 to 800 feet. Tongues of the newer rocks with their accompanying 

 features run westward through Tiverton and Crediton, causing the eastern 

 area to dovetail irregularly into the western. 



It will therefore be seen that the terms eastern and western area are 

 synonymous with the extension of the newer and older rocks respectively. 

 It may not be out of place here to give a brief general outline of the 

 distribution of the rocks in each district and of their general structure, 

 as these have so clear a connection with the physical features of the 

 county, commencing with the older rocks or Palasozoic area. 



The northernmost and most of the southernmost parts of this area 

 are composed of Devonian rocks, the marine sediments of the epoch 

 between the deposition of the Carboniferous and Silurian, during which 

 the Old Red Sandstone was accumulated in lakes and estuaries. 



The Devonian rocks of north Devon, consisting of great alternating 

 masses of slate and sandstone, were deposited in shallower water and 

 nearer to land than the corresponding rocks of the southern district. 

 The latter consist principally of slates with local masses of limestone and 

 contemporaneous volcanic rocks. Grits and silty intercalations are 

 almost entirely confined to the lower horizons which crop out between 

 Staddon Heights on the Plymouth coast and Southdown Cliff near Berry 

 Head, reappearing on the north in the environs of Paignton and in the 

 higher hills of the Torquay promontory. By fossils and by strati- 

 graphical position the rocks of Upper, Middle and Lower Devonian age 

 have been traced, both in the northern and southern outcrops. The 

 strike, or outcrop, of the northern rocks is nearly east and west. The 

 strike distribution of the southern Devonian rocks is in an easterly and 

 westerly direction ; except in parts of the district between Chudleigh 

 and Ivybridge where it is deflected in rough parallelism to the Dartmoor 

 granite boundary. 



The Devonian areas are separated by rocks of Carboniferous age, 

 extending from Tavistock, Okehampton and Ashburton over the great 

 central district to Bideford Bay, Barnstaple and Morebath. 



These rocks are of a type met with in Germany and are called 

 Culm Measures ; they consist of an assemblage of grits, shales and sand- 

 stones with plant remains, upon a series of fine grained sediments with 

 beds of chert, calcareous bands and local limestone developments, con- 

 taining marine fossils. The discovery of Radiolaria in the chert beds by 

 Fox and Hinde' led them to infer that the deposition of these Lower 

 Culm rocks took place in deep water. 



' ^art. Journ. Geol. Soc. (1895), vol. li. pp. 609-67. 

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