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were presented, it would ouly be at the expense of some decided break, such as 

 we find in Dormington AVood or at Lindels ; in fact, the very existence of these 

 ridges at all, instead of a series of irregular bosses, is a matter of surprise. 

 From local reasons, also, at some points the limestone itself might fall and be 

 denuded to the same level as the shale, as between Dormington Wood and 

 Mordiford, leaving a few low heights to mark its place. The whole district 

 should be carefully traversed and surveyed with the help of map, hammer, 

 compass, and clinometer ; and the practised geologist and the tyro will alike reap 

 great benefit from the visit, for we have here presented in a small and compact 

 area some remarkable results of the two great processes, which have mainly 

 caused the present configuration of the earth's surface, upheaval, and 

 denudation. 



UPHEAVAL. 



There cannot be the slightest doubt that the rocks visible in the Woolhope 

 district are made up of sediment deposited upon the same sea bottom with the 

 Upper Silurians about May Hill and between Ledbury and Malvern, and that 

 all these are connected beneath the Old Ked Sandstone with one another and 

 with the rocks of Siluria proper : their lithological composition is the same, 

 their fossil remains are identical, they lie in one and the same order of super- 

 position. What we have first to investigate then is the agency which has 

 thrust up this mass of Upper Silurian rocks through the strata which were 

 deposited upon them. The denudation and degradation resulting from aqueous 

 atmospheric or climatal action were, we must bear in mind, contemporaneous, so 

 far as opportunity allowed, with the upheaval ; but as the causes and processes 

 of upheaval and denudation are entirely distinct and antagonistic, except in the 

 fact that they have combined together to shape out our district to its present 

 figure, it will conduce to greater clearness if we consider them separately. 



The cause of the upheaval has been a continued volcanic action. Sir C. 

 Lyell (Principles, page 577, ed. 1867) has well defined this as "the influence 

 exerted by the heated interior of the earth on its external covering." We 

 must keep this definition in view throughout. Geology, as all other sciences, has 

 suffered much from its nomenclature. When volcanic action is mentioned, 

 the thoughts of some fly off immediately to Vesuvius and Hecla, lava and scoriae ; 

 they wish to be shown the crater. The clear sharp ridges at Woolhope do, 

 indeed, present a remarkable resemblance to the walls of a volcano, and an able 

 astronomer of our Club once pointed out to me the likeness between our 

 district and the annular mountains on the surface of the moon. But at 

 Woolhope no rock appears that is not of strictly Aqueous or sedimentary origin. 

 II we were to probe deep enough beneath the central dome, we should doubtless 

 find the upheaving agent in the shape of a boss of rock belonging to the Igneous 

 class. In a quany at Bartestree, of which more will be said hereafter, a mass 

 of Igneous rock has been injected up a fissure in the Old Red Sandstone with 

 BO clear an evidence of connection with the axial line of the Woolhope district, 



