536 G. Poulett Scrope — On Pretended Raised Beaches. 



Mr. Mackintosh replied in a brief paper, in whicli he refused to 

 accept my correction of his theory (Vol. III. p. 381), declaring that, 

 " so far as his observations have extended, the plough " (to the action 

 of which I had attributed the formation of these terraces) " would 

 appear to obliterate rather than form regular systems of terraces 

 such as he had described." 



In his recently issued volume, " The Scenery of England and 

 Wales ; its Character and Origin," which was reviewed in the 

 October number of this Magazine, Mr. Mackintosh repeats and 

 enforces his views as to the marine origin of these terraces, with 

 a contemptuous allusion to my "Agricultural theory " (p. 9M). 



Now, since the causes which have modelled the existing surface- 

 forms of this island have a real geological interest of no little 

 moment — especially as the same causes, if of a geological character, 

 were no doubt at work very generally throughout the world during 

 the same period, — and as those to which Mr. Mackintosh assigns 

 the terraces in dispute indicate a very recent emergence from the 

 sea, and elevation of the entire island by at least a thousand feet ; 

 and also that this process took place through a series of slight steps 

 or jumps locally of a few feet at a time, corresponding to the 

 intervals of height between the numerously repeated terraces, — the 

 question becomes one not of mere controversy between individual 

 geologists, but of some importance in its bearing on general 

 geological history. This consideration will, I hope, be my sufficient 

 excuse for once more calling attention to the matter in dispute 

 between Mr. M. and myself. I must refer the readers of the 

 Magazine to my paper already mentioned (July 1866, p. 293) for 

 the arguments employed by me in support of the agricultural origin 

 of these terraces, popularly called Lynchets, or Balks, being un- 

 willing to repeat them here. But as Mr. Mackintosh reproduces his 

 theory of their marine origin in his present volume, with some 

 additional illustrations and examples, I will quote some passages 

 from that work in order to show the extent to which, if adopted, it 

 would carry us, appending as we go on a few brief comments. 



In p. 85, he instances " the successive levels of the Brent knoll 

 and its connected platform " as " terraces of marine erosion, which 

 could never have answered any human purpose,''^ but which may be 

 explained by "the action of a not very powerful sea, at different 

 tidal levels, during a gradual rise of the land." How or why these 

 levels could not have answered the purpose of facilitating the 

 culture of the steep slope — especially to the population which at 

 one period encamped for safety on the summit of the knoll, Mr. 

 M. does not explain. He proceeds to say, " In the adjoining 

 district traversed by the Glastonbury and Temple Combe Junction, 

 a geologist becomes bewildered among the thickly crowded variety 

 of these denudational phenomena. Among them he can here 

 and there discover single terraces and sets of terraces, nearly all 

 corresponding to the outcrop of the strata, and therefore not artificial." 



"Why so ? If the outcrop of a stratum or series of strata of rock 

 harder than the rest, on the slope of a hill, be tolerably horizontal, 



