Siluria: the history of the oldest known rocks containing organic remains, with a brief sketch of the distribution of gold over the earth by Sir Roderick Impey Murchison
John Murray, 1854 - 523 Seiten
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abundant animals Atrypa auriferous band Barrande beds Bohemia brachiopods Britain British calcareous Caradoc Caradoc sandstone carboniferous rocks characteristic coal coal-fields conglomerates contain corals crustaceans crystalline deposits described detected Devonian Devonian rocks district England eruptive exhibited fishes flagstones flank forms Foss fossiliferous fossils genera genus Geol geological geologists gold government surveyors granite graptolites grey greywacke grit Hills igneous rocks Journ known Lingula Llandeilo Llandeilo flags Llandeilo formation Lond Longmynd Lower Silurian Lower Silurian rocks lowest M'Coy masses mineral North Wales numerous occur Old Red Sandstone older organic remains Orthidae Orthis Orthoceratites overlying palaeozoic Pentamerus Permian Phacops plants portion primeval Professor Sedgwick Quart Rhenish Russia Salter schists Scotland shale shells Shropshire Silurian fossils Silurian strata Silurian System slates slaty species Spirifer stone strata Syst thickness tracts trilobites Upper Silurian rocks Ural Mountains Verneuil Wenlock limestone Wenlock shale whilst woodcut Woolhope
Seite 447 - Impressed with the conviction that gold would, sooner or later, be found in the great British colony, I learned in 1846 that a specimen of the ore had been discovered. I thereupon encouraged the unemployed miners of Cornwall to emigrate and dig for gold, as they dug for tin in the gravel of their own district. These notices were, as far as I know, the first published documents relating to Australian gold.
Seite 23 - He sees before him an enormous pile or series of early subaqeous sediment originally composed of mud, sand, or pebbles, the successive bottoms of a former sea, all of which have been derived from preexisting rocks ; and in these lower beds, even where they are little altered, he can detect no remains of former creatures. But lying upon them, and therefore evolved after, other strata succeed, in which some few relics of a primeval ocean are discernible, and these again are every where succeeded by...
Seite 12 - ... of the planet. Then it was, that looking to the whole history of former life, as exhibited in the strata, it was demonstrated from phenomena in one great empire alone (as had to a great extent been shown in Britain), that during the formation of the sediments which compose the crust of the earth, the animal kingdom had been at least three times entirely renovated ; the secondary and tertiary periods having each been as clearly characterized by a distinct fauna as the primeval series.
Seite 23 - that all the earliest sediments have been so altered as to have obliterated the traces of any relics of former life which may have been entombed in them, is opposed by examples of enormously thick and often finely levigated deposits beneath the lowest fossiliferous rocks, and in which, if many animal remains had ever existed, more traces of them would be detected.
Seite 240 - In no other tract of the world visited by me have I seen such a mass of red rocks (estimated at a thickness of not less than 10,000 feet) so clearly intercalated between the Silurian and the Carboniferous strata.
Seite 456 - Of these, though they are the lowest in the scale of the great division vertebrata, we are unable to perceive a vestige until we reach the highest zone of the Upper Silurian, and are about to enter upon the Devonian period. Even on that horizon, the minute fossil fishes, long ago noticed by myself, are exceedingly scarce, and none have since been found in strata of higher antiquity.
Seite 500 - ... own country. The large extinct British quadrupeds necessarily required a great range for their sustenance. They had doubtlessly roamed from distant tracts to our lands before the straits of Dover were formed and before the British dominions were broken into isles. Our great insular dislocations were, I conceive, coincident with that striking phenomenon in the Alps on which I have tried to rivet your attention, when the first glacial and icy period affected so large a portion of this hemisphere,...
Seite 478 - ... by which extensive fields of ice were first formed upon the sea, and large glaciers upon the land. As very lofty mountains in moderate latitudes, and masses of land and water in Arctic or Antarctic regions, are now essentially the seats of glaciers and icebergs ; so we know that these bodies alone have the power of transporting huge erratic blocks from their native mountains to considerable distances by land, or for hundreds of miles over the sea in floating icebergs. Now, of the translation...
Seite 634 - If Mr. Murray has shown good tact in choosing Goldsmith for his first author, he has shown equal judgment in selecting Mr. Cunningham for his editor, who has long devoted himself to the history of the lives and writings of the poets of the past century.
Seite 454 - Providence seems to have originally adjusted the relative values of these two precious metals, and that their relations, having remained the same for ages, will long survive all theories. Modern science, instead of contradicting, only confirms the truth of the aphorism of the patriarch Job, which thus shadowed forth the downward persistence of the one, and the superficial distribution of the other : " Surely there is a vein for silver. The earth hath dust of gold.