200 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 21, 



and from thence to the neighbourhood of the Abberley Hills. Its 

 component stones are often from 3 to 9 inches in diameter ; but, un- 

 like those in the breccias, they are all beautifully rounded ; and, 

 where they touch in the rock, they are not scratched, but indent 

 each other at the points of contact ; the indentations being, I believe, 

 due to the fact, that, while these gravels were still incoherent (they 

 may be dug out now with pickaxe and shovel) over great areas, the 

 upper parts of the New Red series, the Lias, and perhaps other newer 

 strata, were piled upon them, and the vertical pressure, consequent 

 on this vast superincumbent pile, induced a lateral pressure in the 

 loose-lying pebbles of the conglomerate ; so that, being squeezed, 

 not only downwards, but outwards, they ground on each other, and, 

 partly by the aid of intervening grains of sand, circular indentations 

 were formed, sometimes an inch in diameter. Occasional earthquake- 

 waves would assist this process. These marks rarely occur in the 

 Permian breccia ; for, whereas in the case of the conglomerates we 

 have sand mingled with the pebbles in the breccias, we find 



4th. A hardened cementing mass of red marl, in which the stones 

 are very thickly scattered, and which in some respects may be com- 

 pared to a red boulder-clay, in so far that both contain angular 

 flat-sided and striated stones and boulders brought from a distance. 



I conceive, therefore, that the peculiar forms, polish, and markings 

 of many of the stones indicate that these characteristics have been 

 produced by the agency of ice of the nature of glaciers, for mere 

 coast-ice would have picked up and drifted away numerous rounded 

 pebbles from the beach, and not a great majority of angular flattened 

 stones, such as form the breccias wherever they occur. 



If this conclusion be correct, and if the parent rocks whence 

 the stones were derived be properly identified, then it follows that the 

 ancient territory of the Longmynd and the adjacent Lower Silurian 

 rocks, having undergone many mutations, at length gave birth to the 

 glaciers, which, flowing down some old system of valleys, reached the 

 level of the sea, and, breaking ofl" into bergs, floated away to the east 

 and south-east, and deposited their freights of mud, stones, and 

 boulders in the neighbouring Permian seas. 



The few fragments of granite and syenite mingled wdth numerous 

 Longmynd fragments in the Malvern area would not invalidate this 

 conclusion, for what more likely than that the floating bergs should 

 sometimes have stranded on or grazed along some of the higher 

 Malvern hill-tops that, as islands, dotted the Permian Sea, and that 

 they thus picked up a few fragments to be mingled and deposited 

 with the foreign material wherever they chanced to melt ? 



It is in vain now to look for the terrestrial indications of these old 

 glaciers on the hills and sides of the existing valleys. The country 

 has passed through too many revolutions and denudations in later 

 periods to permit their traces to remain. It may, however, be asked, 

 what relation do the present levels of the Longmynd and of the 

 breccias bear to each other ? 



The higher points of the Longmynd, Stiper Stones, and Corndon 

 Hill attain a height of from 1500 to 1700 feet above the level of the 



