454 Mr. Austen on the 



porphjTj', that in other places, after having supplied some materials, it became buried under the sand" 

 stone. We thus appear to have ascertained, for one point at least, the limit of the waters of that par- 

 ticular period. Other considerations would seem to point out, that in some places the existing limits 

 are nearly the original ones, such as the gradually decreasing thickness of the sandstone beds westward ; 

 the local character of the deposit in some places already noticed ; the manner in which it terminates 

 abruptly at the base of limestone cliffs, as near Wotton ; and where it follows depressions caused by old 

 disturbances in the slate rocks, as at Bowbridge. 



This formation is distinctly stratified throughout, and it is well known that from Babbacombe to 

 Sidmouth, a distance of twenty miles, the sea-cliffs are entirely composed of it, and that it finally 

 disappears beneath newer formations a little beyond Axmouth, about nine miles farther east. Along all 

 this line the strata dip at a slight angle towards the S.S.E. ; in one place only, on the south side of the 

 Teign, is the inclination reversed, and for a short space the beds are horizontal. Now if we suppose, as 

 has been done, that the order of conglomerates, sandstones and marls is constant throughout this forma- 

 tion, the one carried beneath the other with the same relative dimensions that may be observed in any 

 given section, and if we attempt to estimate the total thickness of the deposit, deduced from the mean 

 angle of its dip, we obtain a result which at once shows that such a supposition must be erroneous, viz. a 

 thickness of little less than five miles for the deposit at Axmouth. 



There is no reason why the divisions of the new red sandstone should be considered as members of an 

 ascending series, although the sandstones seem to overlie the conglomerates, and in turn to be covered 

 by the marls, as, in so doing, we tacitly admit a mode of accumulation very different from that which is 

 at present effected by large bodies of water. Successive additions now take place, as we have seen 

 (p. 4-35), over every part of the bed of the sea simultaneously, wherever particles of matter are carried ; 

 and the distribution of the conglomerates, sandstones and marls, the finer sediment occurring at the 

 greatest distance from the western boundary of the formation, show us the manner in which the deposi- 

 tion of the whole series could proceed contempoi:aneously. 



If we take the coarseness of the conglomerate as a measure of the forces which produced it, and compare 

 it with the effects of the action of the waves of the actual sea upon the very same mineral masses, we shall 

 see no reason to call in the aid " of a stormy and disturbed period, agitated by perpetual convulsions." 

 Such a state of things could never have existed. All the laws by which the stability of large masses of 

 water are maintained must have been in operation during every period, — waves, propagated by whatever 

 cause, must have had their limits confined by the same laws as regulate them now ; nor is a con- 

 trary supposition at all necessary, as no masses occur in the new red conglomerate which exceed in size 

 such as, during every gale, are removed by the waves on our own coasts. The largest porphyritic blocks 

 which fall from the cliffs east of Teignmouth are soon transported away ; and the conglomerate of the 

 raised marine beds of Hope's Nose is as coarse as any that occurs in the new red conglomerate series : beds 

 of conglomerate, of whatever age, indicate the action of breakers and an inconsiderable depth of water. 



The arenaceous beds of this series, as west of Sidmouth, present ripple-markings on their upper sur- 

 faces, and this beneath 200 feet of the deposit in a vertical line. It has been supposed that these 

 markings may be produced under any depth of water, but perhaps erroneously, from the well-known 

 tranquillity which prevails over the bed of the sea, even at the inconsiderable depths to which divers have 

 descended ; the castings of worms are also beautifully preserved over the same slabs of sandstone, — a 

 circumstance, coupled with the former, which would seem to indicate that a gradual encroachment of 

 the sea, or a slow subsidence of its bed, accompanied the accumulation of the deposit in this part of 

 England. 



The bright red colour of the formation, particularly the South Devon portion of 

 it, has not been satisfactorily accounted for. The colouring metals are iron and 



