of the Chalk Downs. 



189 



they would consist of chalk or other rock in situ. But on the 

 contrary they will be found on investigation, I believe, invariably 

 composed of made earth or soil such as would naturally result from 

 the downward wash of the loose surface-materials of the slopes 

 above, annually broken up by the plough through a series of years, 

 and exposed to the influence of subaerial denudation. 



It is indeed remarkable that these terraces, which are brought 

 forward by Mr. Mackintosh as " proofs of the impotence of rain 

 in moulding the earth's surface" since under his theory they have 

 remained unaltered from the distant period when the chalk hills 

 lay to their very summits beneath the sea waves, afford, on the 

 contrary, very pregnant and convincing evidence of the power 

 exercised by rain in altering the configuration of our hill slopes 

 within very recent and limited times. 



G. POULETT SCROPE. 



Fairlaivn, Cobham, Surrey, 

 July 10 th, 1869. 



P.S. — Since this paper was written, a volume has issued from 

 the press, by Mr. D. Mackintosh, " On the origin of the Scenery 

 of England and Wales," in which his views as to the formation of 

 these terraces by the erosive power of sea- waves, or marine currents, 

 is repeated, and what he calls my " agricultural theory " of their 

 origin, alluded to with contempt. 



In the number of the Geological Magazine for December last, I 

 therefore once more controverted Mr. Mackintosh's views, and still 

 further explained my own. With the former object I inserted in 

 my paper a few woodcuts, accurately copied from some of the 

 illustrations to Mr. M.'s volume, which are reproduced here as 

 examples of the general character of the terraces in question. 



No. 1 represents " a series of terraces near Stockbridge on a 



Fig. 1.— Terraces near Stockbridge. 



