198 Eminent Living Geologists — G. Poulett Scrope. 



axial in form), while the matter composing them was in a semi- 

 liquid or viscous state, and subjected to extreme and oblique 

 pressures — a view which he had been led to form and declare, as 

 early as 1824, by a study of the laminated pearlstones and trachytes 

 of the Ponza Isles.^ 



" On the Causes of Earthquakes." (Oeologist, vi. p. 455.) 



" On the Origin of Valleys." (Geological Magazine, Vol, III. p. 192.) 



" On the Origin of Hills and VaUeys." {Ibid. p. 241.) 



" On the Terraces of the Chalk Downs." (Ibid, p, 293.) 



" On Atmospheric Forces." (^Ibid. p. 379.) 



" On the Cause of Faults and Contortions of Strata." {Ibid. Vol. V. p. 339.) 



" On the Supposed Internal Fluidity of the Earth." {Ihid. Vol. VI. p. 145.) 



" On the Influx of "Water as the Cause of Volcanic Eruptions." {Ibid. p. 196.) 



" Review of MM. DoUfus and Montserrat's Geology of Guatemala." {Ibid. p. 455.) 



"Review of Baron Richthofen's System of Volcanic Rocks." {Ibid. p. 510.) 



" On the Pretended Raised Sea-beaches of the Inland Slopes of England and "Wales." 



{Ibid. p. 535.) 

 " On Lavas." {Ibid. Vol. VII. p. 100.) 



In these papers Mr. Scrope, it will be seen, confined himself to 

 the vindication of opinions, already put forward by him in his larger 

 works, upon the phenomena of subterranean or volcanic agency, and 

 also on the influence of " subaerial " — that is to say, atmospheric — ■ 

 agencies in moulding the surface of the earth. In some of these he 

 may, perhaps, be charged with an impatience of what he considered 

 the mischievous fallacies of the writers he opposes, as, for instance, 

 while combating the "upheaval" doctrines of Humboldt and Elie 

 de Beamnont, or the views on " exclusively marine denudation," 

 professed by Mr, D. Mackintosh. But, if this charge be true, it may 

 fairly be attributed to the earnestness with which, as a student of 

 nature and a pi-opagator of scientific truth, he looks on persistence 

 in a false theory, after its fallacy has been fully exposed, as " not 

 merely a fault, but a crime," from its baleful effect in checking the 

 progress of true science. Mr. Scrope, it will be seen, has not 

 allowed himself to be led from the line of geological study which he 

 first traced for himself in early life — namely, that of the igneous and 

 aqueous agents of change, discoverable on the surface of the globe, 

 and their influence on its past history. Commencing his observations 

 at a period when the Huttonian theory was absolutely discoun- 

 tenanced and discredited (1817-23), he perceived intuitively, and 

 proclaimed in his first publication, that one of ihe primary tasks of 

 the geologist is to obtain *' a knowledge of the processes which are 

 in continual or occasional operation upon the surface of our planet, 

 and the application of these laws to explain the appearances dis- 

 covered by our geognostical researches " into the character of its 

 rock formations, ''so as from these materials to deduce conclusions 

 as to its past histoiy" (Preface to first edition of Volcanos, 1825). 

 With this object he devoted himself to an examination of the pheno- 

 mena of volcanos, both active and extinct, taking note, at the same 

 time, of the effects of atmospheric action on the surface of subaerial 

 land ; and the facts he collected and the views he propounded on 



^ See his paper on the Ponza Islands, read before the Geological Society in 1827 

 (Geol. Trans. Ser. ii. vol. ii.) 



