24 



PERMIAN BRECCIAS, 



Upper 

 Gallery. 



Table-case 



in Recess 41 



ancient Silurian beacli in the Longmynd country, and the 

 inference is that they were transported from thence- Along 

 with these " a well-rounded waterworn pebble is of rare 

 occurrence. The surfaces of a great majority of the peb- 

 bles are much flattened, numbers are highly polished, and 

 when searched for, some of them are found to be distinctly 

 grooved and finely striated. The striae in some are clear and 



i 



sharp, and run parallel to or cross each other at various 



while in others, though you see their remains, age 

 and surface decomposition have impaired their sharpness, 

 and roughened the original polish of the stone," In general 

 the surfaces, including the scratches, are covered by a thin 



angles 



ferruginous crust. 



The confused and irregular manner in 



which the whole is bedded, the angularity of all, and the 

 great size of many of the stones, together with the clay in 

 which they lie, present such strong resemblances to much of 

 the " drift " boulder clays, that the appearances may almost be 

 said to be identical. All the places where the breccias occur 

 lie from 25 to 45 miles from the presumed parent rocks ; and 

 few English geologists now believe that unrounded boulders 

 sometimes several feet in diameter, and deposits of this kind 

 generally, could have been carried so far, either by ordinary 

 marine currents or by assumed violent floods. I believe 

 that only the transporting power of floating ice, long con- 

 tinued, could have produced results of such magnitude, 

 marked by the peculiarities above described. The rock is 

 of the same age as the German Roth-todte-liegende, and is 

 identical with it in general appearance 



to 



further 



details, see " Journal of the Geological Society," August 



1855, p. 185. 



) 



Pieces of Pi 



if stones collected fk 



100. — From Woodbury Bock, Knightsford Bridge, Abberley 



Uills. 



