68 

 ADDRESS ON THE GEOLOGY OF THE DISTRICT. 



BY THE REV. W. S. SYMONDS, M.A., F.G.S., 



PRESIDENT OF THE MALVERN NATURALISTS' FIELD CLDB. 



Ladies and Gentlemen, — When I received a request from your president 

 and my friend Dr. Bull that I would undertake to deliver an addiess upon the 

 Geology of the District we have visited to-day, I felt somewhat embarrassed 

 as to the manner in which I should treat the subject, and whether I should give 

 you a palceontological history of the rocks and the various organisms they 

 contain, or whether I should deal more particularly with the physical geology, 

 and describe, though necessarily very briefly, the way in which I conceive the 

 hiUs and vales by which we are now surrounded to have been moulded into 

 their present shapes, and assumed their present outlines of rock and hill, deep 

 valleys and high table lands. 



When the young geologist comes for the first time to the physical study 

 of mountain scenery, and examines the crags and vales, the ravines and pre- 

 cipices, with fragments of rock lying strewn over the sides and in the hollows, 

 he is very apt to attribute the broken features he beholds to convulsions caused 

 by the volcano, and the earthquake, which hurled up the mountains and threw 

 down the glens and rent asunder the valleys, down which now flow the rivers 

 and the brooks. I am old enough to remember the time when almost every hiU 

 in Wales was attributed to a catastrophic elevation, and every valley was believed 

 to have originated in an earthquake rent. As years passed by sounder views 

 respecting the origin of such scenery have been arrived at, and we have learned 

 to attribute the principal existing features of the land we inhabit, whether we 

 live among the mountains, by the sea- side, or in the river vales, to the operation 

 of pre-existing and natural causes, which in the glacier and snow drift were 

 at work for unnimibered ages, and natural causes which are still at work 

 through the action of frost and snows, rain, rivers, brooks, tides, in short all the 

 many agents of subaerial denudation which may now be observed in full action 

 upon the surface of this planet, mouldering the hills, and wearing and carrying 

 away the rocks. I must not, however, be misunderstood, and supposed to say 

 that the hill and mountain configuration of many districts visited by the Wool- 

 hope Club in their distant explorations does not owe much to the eruption of 

 volcanic materials, and large accumulations of ancient lavas and volcanic ashes, 

 which were poured during earthquake convulsions into the beds of seas which 

 no longer exist, and which lava currents often stand out as bold hiU rocks, and 

 serve as protectors of the softer sea-beds among which they are frequently 

 interstratified. During the period of the deposition of the Lower Silurian rocks 

 there must have been active volcanos in several parts of Wales and Siluria, 

 and probably volcanic islands were formed around the volcanic vents. In the 

 neighbourhood of Builth, some 20 miles distant, as the crow flies, many animals 



