TERRACES IN IRELAND. 35 



England. 



I traversed England in various directions, and yet generally over its more level 

 parts, and did not see much evidence of drift agency, nor many terraces. The latter 

 I did not expect to find well developed, save in regions where rivers are bordered 

 by hills of considerable elevation, so arranged as to form basins. Yet I did expect 

 to see them on the romantic banks of the Wye, but was disappointed; though 

 materials exist, they are not well formed into terraces. And the same is true of 

 all the streams of England where I passed them. Beds of gravel and sand do, 

 indeed, occur extensively, but they seemed to me to be beaches, or rather old sea 

 bottoms, and not terraces, and many of them sandy and gravelly bottoms of former 

 seas, belonging to a period anterior to the drift, being the beds of tertiary strata. 



Very probably good examples of terraces may be found in the more hilly parts 

 of England ; and geologists describe deposits of drift derived from Scandinavia and 

 Scotland. But they generally make no distinction between drift and remodelled 

 and comminuted drift, which last forms deposits of far posterior date. I think I 

 see in their descriptions, however, marks of what I call ancient beaches and sea- 

 bottoms of postdiluvian date. 



Ireland. 



I visited only the northeast of Ireland, passing from Dublin to Belfast, through 

 Dundalk, Castleblayney and Armagh ; from Belfast, along the coast, to Fair Head, 

 and the Giant's Causeway, and from thence back to Belfast, through Ballymoney, 

 Ballymena, Antrim, and Carrickfergus. A little south of Castleblayney, I met 

 with genuine unmodified drift, scattered over the slate and silurian rocks, and I saw 

 strias and embossed rocks ; the direction of the striae being from northwest to south- 

 east nearly. Here, also, were frequent examples of what I suppose to be the 

 Swedish Osar, viz., ridges of sand and gravel running northwest and southeast, the 

 rounded summit sloping very gradually, especially at its southeast extremity. At 

 the other end the slope is not so distinct, and indeed the ridge is sometimes termi- 

 nated by some obstruction. 



In Col. Portlock's " Report of the Geology of Londonderry, Tyrone, and Fer- 

 managh," which lie north and northwest from the region I am describing, he states 

 "that these trains of sand and gravel are found at an elevation of nearly 1000 

 feet." He says, also, that "in the eastern parishes of Derry the form of detritus 

 is peculiar and beautiful. It appears like so many streamers attached to each 

 basaltic knoll, and directed from north to south." These ridges are somewhat dif- 

 ferent from any that I have observed in the United States ; or rather, they seem 

 more distinctly to be the result of a current heaping up materials behind some 

 obstruction; precisely, in fact, what we see in the beds of our large rivers, or 

 smaller lakes. Whereas, with us, similar ridges, which I denominate Moraine Ter- 

 races, are often curved, have steeper escarpments, and do not seem connected with 

 obstructions. 



