"Silurian" Quotes from Famous Books
 ... yet in a chaotic and formative condition; huge slides of Silurian slates and diorite are of frequent occurrence. A ridge of one of these softer stones had most probably been encased in the surrounding granite for many centuries; then, loosened by water or by time, had crumbled and slid into ...
— Under the Andes • Rex Stout
... possible knowledge of the early world and its inhabitants, we must compare, not the area of the whole field of our geological researches with the earth's surface, but the area of the examined portion of each formation separately with the whole earth. For example, during the Silurian period all the earth was Silurian, and animals were living and dying, and depositing their remains more or less over the whole area of the globe, and they were probably (the species at least) nearly as varied in different ...
— Contributions to the Theory of Natural Selection - A Series of Essays • Alfred Russel Wallace
... area, and to have extended thence through boreal and arctic latitudes into North America. Of the height and mass of this primeval land some idea may be formed by considering the enormous bulk of the material derived from its disintegration. In the Silurian formations of the British Islands alone there is a mass of rock, worn from the land, which would form a mountain-chain extending from Marseilles to the North Cape (1800 miles), with a mean breadth of over thirty-three miles, and an ...
— The Antediluvian World • Ignatius Donnelly
... classed as pre-Cambrian, occur as several unconformable groups, chiefly developed in the south where alone their stratigraphy has been determined. They are unfossiliferous, and in the absence of undoubted Cambrian, Ordovician and Silurian strata in Africa they may be regarded as of older date than any of these formations. The general occurrence of jasper-bearing rocks is of interest, as these are always present in the ancient pressure-altered sedimentary ...
— Project Gutenberg Encyclopedia
... this continent, north-west of Minnesota, and known as the Saskatchewan district, is estimated by English authorities to comprise 368,000 square miles. North-west from Otter Tail Lake, the geographical centre of Minnesota, extends a vast silurian formation, bounded on the west along the eastern base of the Rocky Mountains by coal measures. Such a predominance of limestone implies fertility of soil, as in the north-western States, and the speedy colonisation of Saskatchewan would be assured if the current objection to the severity ...
— Handbook to the new Gold-fields • R. M. Ballantyne
... misled by trusting to lithological evidence; yet his reasoning all through Siluria, shows that he still thinks it natural to expect formations of the same age to be chemically similar, even in remote regions. For example, in treating of the Silurian rocks of South Scotland, he says:—"When traversing the tract between Dumfries and Moffat, in 1850, it occurred to me, that the dull reddish or purple sandstone and schist to the north of the former ...
— Essays: Scientific, Political, & Speculative, Vol. I • Herbert Spencer
... hard, and very little enrichment by weathering has taken place; they carry in their richer portions 70 to 80 per cent calcium phosphate, and large sections range only from about 30 to 50 per cent. In the southeastern deposits (Silurian and Devonian in Tennessee and Tertiary in the Carolinas and Florida), there has been considerable enrichment, the rock is softer, and the general grade ranges from 65 to 80 per cent. Both calcium carbonate and calcium ...
— The Economic Aspect of Geology • C. K. Leith
... with the crowd of fishes pressing to the only outlet, there to meet their death. Various forms of fish-mouths peep out of the water—transparent jelly-fish, red tails, blue, green, and silver scales press up, and between them comes up sometimes a great silurian, the shark of the Balaton, a Wels of a hundred pounds' weight, with wide jaws and horse-shoe mustache; but it disappears into the depths again, as if to find ...
— Timar's Two Worlds • Mr Jkai
... awaited Margaret and her companions. Arithmetic and slates! Does anyone remember—can anyone forget—how horribly distasteful a slate can be when the icy fingers of youth have to clasp that cold educational formation (Silurian, I believe), and to fumble with the greasy slate-pencil? With her Colenso in her lap, Margaret Shields grappled for some time with the mysteries of Tare and Tret. "Tare an' 'ouns, I call it," whispered Janey Harman, who had taken, in the holidays, a "course" of Lever's Irish novels. ...
— The Mark Of Cain • Andrew Lang
... some family probably near to Cancellaridae. It is certainly entirely distinct in every respect from any known Gasteropod. It is a form of very great interest to the geologist, for in it we see the nearest representation of certain palaeozoic (especially Lower Silurian) univalves hitherto referred to Littorina, but which, judging from their associates and the indications afforded by the strata in which they are found, were assuredly either inhabitants of deep water or floaters in a great ocean ...
— Voyage Of H.M.S. Rattlesnake, Vol. 2 (of 2) • John MacGillivray
... "Colonies" (41/3. Lyell briefly refers to Barrande's Bohemian work in a letter (August 31st, 1856) to Fleming ("Life of Sir Charles Lyell," II., page 225): "He explained to me on the spot his remarkable discovery of a 'colony' of Upper Silurian fossils, 3,400 feet deep, in the midst of the Lower Silurian group. This has made a great noise, but I think I can explain away the supposed anomaly by, etc." (See Letter 40, Note.) and his agreement with E. de Beaumont's lines of Elevation, or such men as ...
— More Letters of Charles Darwin - Volume I (of II) • Charles Darwin
... if the "nexts" would grow on so that at last it would only be our old "set" that would be in any danger of getting left out. "Society is like a coral island after all," says Leslie Goldthwaite. "It isn't a rock of the Old Silurian." ...
— We Girls: A Home Story • Mrs. A. D. T. Whitney
... thirdly, of all the terrestrial animals, which now exist—during distinct intervals of time; modern science teaches that, throughout all the duration of an immensely long past so far as we have any adequate knowledge of it (that is as far back as the Silurian epoch), plants, aquatic, aerial, and terrestrial animals have co-existed; that the earliest known are unlike those which at present exist; and that the modern species have come into existence as the last terms of a series, the members of which have ...
— Collected Essays, Volume V - Science and Christian Tradition: Essays • T. H. Huxley
... attached the greatest importance. In Wales he took up the question of the age of the rocks in the neighbourhood of Dolgelly, and after much study of their fossils proposed the now accepted classification of the Lingula flags of the Lower Silurian system into the Maenturog flags and slates, the Festiniog flags, and the Dolgelly slates. The collecting of lepidoptera was his chief amusement in Brazil, where he made his first acquaintance with the ...
— The Naturalist in Nicaragua • Thomas Belt
... other irregularly. The ore-bed in which the remains were found, and part of which seems to have formed after the period of human occupation of the cave, lies in the second (or saccharoidal) sandstone of the Lower Silurian." ...
— Ragnarok: The Age of Fire and Gravel • Ignatius Donnelly
... of the lower vertebrata (Elasmobranch and Ganoid fishes) occur, indeed, in early strata (upper Silurian); but still far from the earliest in which some of the invertebrata are found. The general statement in the text applies chiefly to the more highly organised forms of ...
— The Scientific Evidences of Organic Evolution • George John Romanes
... a simple tube in the Leptocardii; it divides itself into two cavities in the fishes, into three in the reptiles, and into four in the birds and mammals. So the ossification of the vertebral column takes place progressively, from the Silurian to ...
— Time and Change • John Burroughs
... forms of life are the lineal descendants of those which lived long before the Silurian epoch, we may feel certain that the ordinary succession by generation has never once been broken, and that no cataclysm has desolated the whole world. Hence we may look with some confidence to a secure future of equally inappreciable length. And as natural selection works ...
— The Idea of Progress - An Inquiry Into Its Origin And Growth • J. B. Bury
... transitional form. These fishes have organs as complex and perfect as the fishes of to-day. Suddenly, in the "carbonic age" amphibia and reptiles appear, and then come, in the "Triassic" the huge reptiles known as dinosaurs. Insects and scorpions have been found in the "Silurian." [tr. note: sic on punctuation] They stand among the highest of even living articulates, and they are the "oldest" known airbreathing animals. "We seek in vain for the progenitors of these highly organized articulates or for some conceivable method by which ...
— Evolution - An Investigation and a Critique • Theodore Graebner
... through a place called absurdly enough Paris, from the quantity of gypsum with which the neighbourhood abounds; and fine specimens of silurian fossils of the trilobite family and of madrepores, millepores, and corallics, are found here. Love's Hotel is the best in the village, and a good one ...
— Canada and the Canadians, Vol. 2 • Richard Henry Bonnycastle
... structure than in any of the forms we have hitherto considered. Forms closely related to it occur among the earliest remains of vertebrata that are to be found in the geological record. Since the immeasurably remote Silurian period, sharks and dog-fish have probably remained without any essential changes of condition, and consequently without any essential changes of structure, down to the present day. Then, as now, they dominated the seas. They probably branched off from the other vertebrata before bone ...
— Text Book of Biology, Part 1: Vertebrata • H. G. Wells
... abundant fauna of mixed mesozoic and palaeozoic types, in rocks of an epoch once supposed to be eminently poor in life; witness, lastly, the incessant disputes as to whether a given stratum shall be reckoned devonian or carboniferous, silurian or devonian, cambrian ...
— Darwiniana • Thomas Henry Huxley
... time in what were then supposed to be the most ancient fossiliferous beds. When Agassiz first began his researches on fossil fishes, no vertebrate form had been discovered below the coal. The occurrence of fishes in the Devonian and Silurian beds threw the vertebrate type back, as he believed, into line with all the invertebrate classes, and seemed to him to show that the four great types of the animal kingdom, Radiates, Mollusks, Articulates, ...
— Louis Agassiz: His Life and Correspondence • Louis Agassiz
... indefatigable Ehrenberg had discovered that the "greensands" of the geologist were largely made up of casts of a similar character, and proved the existence of Foraminifera at a very ancient geological epoch, by discovering such casts in a greensand of Lower Silurian age, which ...
— Discourses - Biological and Geological Essays • Thomas H. Huxley
... the first form which existed of each of the great divisions would present points intermediate between existing ones, but immensely different. Most geologists believe Silurian{117} fossils are those which first existed in the whole world, not those which have chanced to be the oldest not destroyed,—or the first which existed in profoundly deep seas in progress of conversion from sea to land: if they ...
— The Foundations of the Origin of Species - Two Essays written in 1842 and 1844 • Charles Darwin |
