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"the evolution of the mourne mountains." 



The usual weekly meeting of the Club was held on 

 March 7th, in the Museum, College Square North. The 

 President (Mr. W. H. Phillips) occupied the chair, and briejfiy 

 called upon Mr. W. J. C. Tomlinson tO' read his paper on "The 

 Evolution of the Mourne Mountains." 



Mr. Tomlinson, in introducing his subject, referred to the 

 rise and progress of the science of geology in the last century. 

 During that period great changes came over the views held by 

 scientific men regarding the physical history of the earth, and 

 over their ideas regarding the origin and permanence of our 

 present mountain forms. The traditional, but rather incorrect, 

 views in vogue in earlier times came with the progress of in- 

 vestigation to be discarded. The study of field geology and 

 the observation of the forces of nature led students of the new 

 science to the conclusion that mountains, as a rule, are not the 

 outcome of recurring catastrophes. The truth was brought 

 home irresistibly to the patient observer that the slow, steady 

 sculpturing carried on from age to age by nature's eroding and 

 denuding agents was ample enough to produce all the outward 

 features we witness in the present aspects of our hills and 

 valleys. The British school of geologists has always been so 

 deeply engrossed in studying the stratigraphical relationship 

 and character of the various rock formations that the dynamical 

 questions involved in all theories of mountain architecture have 

 not received from them that full consideration which is their 

 due. This reproach, however, is now beginning to disappear. 

 On the other hand, American geologists, who in the pursuit of 

 their studies were confronted by geological phenomena on a 

 tremendous scale, both as regards magnitude and complexity, 

 v.ere forced to bestow upon dynamical geology that considera- 

 tion which it merited. Their conclusions are pregnant with the 

 most fertile ideas now extant regarding the history of mountain 

 building. The study of the structural geology of mountain 

 groups has led the foremost expositors of the science to adopt 

 a three-fold classification for all existino; terms. These are — 



