238 NEW RED SANDSTONE. 



Other places for building-purposes. The Wonford stone was used 

 in the construction of the sea-wall at Torbay, and was formerly 

 used for coarse millstones. Sandstone from the cliffs east of 

 Exmouth was used in Exeter Cathedral. The beds are very 

 irregularly impregnated with iron-ore, and this has influenced the 

 weathering of the red cliffs, which, especially near Dawlish, assume 

 grotesque forms. Sometimes the sand is very dark and almost 

 black. Some of the brecciated clay-beds in the neighbourhood of 

 Exeter and near Torre are worked for brick and tile-making. The 

 red clay used in the Terra Cotta works at Watcombe (Watcombe 

 and Petitor sands and clays) has been shown by Mr. Ussher to 

 occur at the base of the Red rocks, although superficial loamy 

 deposits have also been employed in the manufacture of this 

 earthenware.^ 



The lower beds of Breccia between Teignmouth and Exeter have 

 been long known to contain opalescent crystals of a variety of 

 felspar known as Murchisonite, evidently derived as pebbles from 

 the granitic or igneous rocks (quartz-porphyry, etc.) of the Dart- 

 moor district, yet differing a little in colour and texture from the 

 mineral when found in situ. Mr. Ormerod has endeavoured to 

 trace out certain horizons in this series by the occurrence of 

 Murchisonite, whence the name * Murchisonite beds,' which he has 

 applied to the strata.- Some Igneous rocks are associated with 

 the beds near Tiverton, Crediton, and Exeter. (See sequel.) 



As yet we have no positive proof, by any deep-boring, that the 

 separate divisions that are visible in the coast-section between 

 Teignmouth and Axmouth are continuous one beneath the other, 

 so that at the latter locality all would be represented in vertical 

 section were a boring carried through the series ; and when the 

 question of the method of accumulation of the strata comes to 

 be solved some difficulties arise. ^ 



It may be observed that nowhere are the conglomerates and 

 breccias far removed from the margin of old rocks, but the pebble- 

 beds of Budleigh Salterton are seemingly the most distant from 

 their parent rocks. The former are all of local derivation, varying 

 according to the characters of the Palaeozoic rocks against which 

 they rest. The derivation of some of the latter is not exactly 

 known ; the fossils collected by Mr. W. Vicary, Mr. W. Linford, 

 and others, indicate species of Devonian and Cambrian age ; and 

 at one time the older pebbles were considered to have travelled 

 from the French area, as Mr. J. W. Salter regarded the fossils 

 as French, and not British species, and similar rocks occur in 

 Normandy, Brittany, etc. It is now considered that they may have 

 been derived from rocks at no very great distance from the spots 

 where the pebbles are found ; perhaps, as has been suggested, 

 from Gorran Haven, Mevagissey, and Veryan, or more probably 



1 Trans. Devon Assoc. 1877 ; A. Tyler, Q. J. xxii. 466. 



* Q. J. xxxi. 346 ; see also De la Beclie, Report on Geol. Cornwall, etc. p. 208. 



^ See Godwin-Austen, T. G. S. (2J, vi. 454. 



