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Show 'Vi CONTENTS. PAGE CHAPTER IV. Werner's application of Geology to the art of Mining-Excursive character of his lectures-Enthusiasm of his pupils-His authority-His theoretical errors-Desmarest's map and description of Auvergne-Controversy between the Vulcanists and Neptunists-Intemperance of the rival Sects-Hutton's theory of the Earth-His discovery of granite veins-Originality of his views-Why opposed-Playfair's illustrations-Influence of Voltaire's writings on Geology-Imputations cast on the Huttonians by Williams, Kirwan, and De Luc-Smith's map of England-Geological Society of LondonProgress of the Science in France-Growing importance of the study of or-ganic remains 55 CHAPTER V. Review of the causes which have retarded the progress of Geology-Effects of prepossessions in regard to the duration of past time-Of prejudices arising from our peculiar position as inhabitants of the land-Of those occasioned by our not seeing subterranean changes now in progress-All these causes combine to make the former course of Nature appear different from the present -Several objections to the assumption, that existing causes have produced the former changes of the earth's surface, re~oved by modern discoveries 76 dHAPTER VI. Proofs thai the climate of the Northern hemisphere was formetly hotterDirect proofs frotrl the Organic remains of the Sicilian and Italian strataProofs from analogy derived from extihct Quailrupeds-Imbeddirtg of Ani. mals in Icebergs-Siberian Mammoths-Evidence in regard to temperature, from the fossil remains of tertiary and secondary rocks-From the plants of the coal formation 92 CHAPTER VII. On the causes of vicissitudes in climate-Remarks on the present diffusion of heat over the globe-On the dependence of the mean temperature on therelative position ofland and sea-Isothermal lines-Currents from equatorial re· gions-Drifting of Icebergs-Different temperature of Northern and Southern hemispheres-Combination of causes which might produce the extreme cold of which the earth's surface is susceptible-On the conditions necessary for \he ~roduction of the extreme of heat, and its probable eff~:~cts on organic life 104 CONTENTS. CHAPTER VIII. Geological proofs that the geographical features of the northern hemisphere, at the ptlriod of the deposition of the carboniferous strata, were such as would, according to the theory before explained, give rise to an extremely hot climate -Origin of the transition and mountain limestones, coal-sandstones, and coal -Change in the physical geography of northern latitudes, between the era of the formation of the carboniferous series and the lias-Character of organic remains, from the lias to the chalk inclusive-State of the surface when these deposits originated-Great accessioh of land, and elevation of mountain-chains, between the consolidation of the newer secondary and older tertiary rocksConsequent refrigeration of climate-Abrupt transition from the organic remains of the secondary to those of the tertiary strata-Maastricht beds-Re- 'Vii marks on the theory of the diminution of central heat • 125 CHAPTER IX. Theory of the progressive development of organic life considered-Evidence in its support w_holly inconclusive-Vertebrated animals in the oldest strataDifferences between the organic remains of successive formations-Remarks on the comparatively modern origirt of the human race-The popular doctrine of successive development not confirmed by the admission that man is of modern origin-In what manner the change in the system caused by the introduction of man affects the assumption of the uniformity of the past and future course of physical events • 144 CHAPTER X. Division of the subject into changes of the ~rganic and inorganic worldInorganic causes of change divided into the aqueous and igneous-Aqueous causes-Destroying and transporting power of running water-Sinuosities of rivers-Two streams when united do not occupy a bed of double surfaceHeavy matter removed by torrents and floods-Recent inundations in Scotland- Effects of ice in removing stones-Erosion of chasms through hard rocks-Excavations in the lavas of Etna by Sicilian rivers-Gorge of the Simeto-Gradual recession of the cataracts of Niagara-Speculations as to the time required for their reaching Lake Erie l6i' CHAPTER XI. Action of running water, continued-Course of the Po-Desertion of its old ~hannel-Artificial embankments of the Po, Adige, and other Italian rivers-Basin of the Mississippi-Its meanders-Islands-Shifting of its |