Journal of the Royal Geological Society of Ireland, Volumen5 |
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Términos y frases comunes
action angles appears Ballycotton bands Bantry Bay basalt beds boulders brachiopoda C. W. Hamilton calcareous Captain Portlock carbonate carboniferous chalk clay coast colour conglomerate contortions copper County crust crystalline crystals D'Orbigny December deposits Devonian district disturbance drift Dublin dykes earth earth-wave elevation epoch eruption exhibited fact feet felspar formation fossils genera Geological Society geologists glacier granite gravel graywacke greenstone Haughton hills hornblende igneous rocks Ireland iron James Apjohn John Scouler Journal June lime limestone lode M'Adam magnesia magnetic mass matter mica miles mineral observed occur old red sandstone oolitic peculiar phenomena porphyry portion present probably produced Professor Oldham pyrites quantity quartz rock remarkable Richard Griffith Robert Mallet sand scratches serpentine shale shell shore silica Silurian slate slaty species strata stratified surface tertiary thickness tion traces trap upper veins volcanic whilst Wicklow WILLIAM EDINGTON Zoantharia
Pasajes populares
Página 6 - Proceedings of the Geological and Polytechnic Society of the West Riding of Yorkshire, 1847.
Página 206 - An address delivered at the anniversary meeting of the Geological Society of London, on the 19th of February, 1841 ; and the announcement of the award of the Wollaston medal and donation fund for the same year.
Página 207 - Map of that part of the mineral lands adjacent to lake Superior, ceded to the United States by the treaty of 1842 with the Chippewas.
Página 6 - Memoirs of the Geological Survey of the United Kingdom. Figures and Descriptions illustrative of British Organic Remains.
Página 27 - ... range of our observation, are mutually convertible, and both convertible into heat. Currents of both we know are ever passing, with variable activity, through enormous volumes of the earth's crust, the different parts of which possess very different conducting powers. Can it be that these currents, constrained to pass through narrow and bad conductors, at vast depths in some formations, ignite them in their progress ? Will it be found that the great lines of volcanic activity (as dreamed...
Página 27 - But by what force was that crust thus torn asunder, and streams of mineral matter forced through it? Mr. Mallet appears to adopt electric agency as the great final cause which has produced such results. " Thus, then," he says, " ignorant as we are of all within the outer surface or skin of our globe, we are compelled to see the close connexion of these mighty heating powers, in which ignition is present on the vastest scale, yet without combustion^ with the forces of terrestrial electricity and magnetism...
Página 74 - ... not seem altogether reduced in comparison with the other two, if we could not be satisfied that its perfect period of development were the former geological ages when its numbers were far greater than at present, a circumstance which places the whole class in peculiar relations to its type, which must be rather appreciated under the point of view of the conditions which prevailed in former ages, when the ocean covered more extensively the whole surface of the globe than at present ; so that the...
Página 72 - ... animals and the surrounding media in which they live has of late been so entirely disregarded, that it is time to reconsider this question with all the attention ,-- its importance demands, since we find in it a decided relation to the structure and functions of all animals. For though it is plain that the mere living in water or upon dry land is in itself of slight importance, as there are so many animals which dwell in the two elements, although having the same identical structure, it should...
Página 130 - On the National Importance of studying Abstract Science, with a view to the healthy Progress of Industry, by Lyon Playfair.
Página 49 - Mr Greenough, not considering the force of running water, either as exhibited in the torrents of rivers or in the sea, sufficiently great to account for such results, ascribes them to the deluge. Hutton had ascribed them to the tumultuous rush of water consequent on great debacles, the result of sudden elevations of mountain chains and masses. Dr M'Culloch, in his System of Geology (1831), observes in his chapter on Changes in the Disposition of the Sea and Land, " But I must not omit one argument...