The Quarterly Journal of the Geological Society of London, Volume 6The Society, 1850 - Electronic journals Vols. 1-108 include Proceedings of the society (separately paged, beginning with v. 30) |
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Common terms and phrases
abundant accumulation Alenquer Ammonites angle ankerite appears Arenaceous shale argillaceous Argillaceous shale beds belong calcareous Cape Mondego carbonate carboniferous chalk Channel character cliffs coal coast Coimbra columella conglomerate containing crater cretaceous D'Orb d'Orbigny denudation deposits depth Desh district elevation Eningen eocene eruption feet ferruginous folds formation fossils fragments Franç genus Geol geological Goldf granite gravel greensand hills hippurite limestone inch island Jurassic Kimmeridge clay lava layers limestone Lisbon London clay lower margin marl mass miles mineral Mondego Monte n. s. PL nearly numerous Nummulites observed occur oolite organic remains pebbles period PLATE portion present quarry R. I. Murchison Radoboj red sandstone resembles river rocks sand seen shells side Silurian slate species specimens Stigmaria strata subcretaceous series surface tertiary Testa thickness tion traces trachyte Underclay Underclay Stigmaria upper valley valve veins volcanic whilst whorl
Popular passages
Page 305 - This river is several hundred miles in length, and from half a mile to a mile and a half in breadth, and winds through a hilly, and in many places a fertile and highly cultivated country.
Page 2 - REPORT ON THE GEOLOGY OF THE COUNTY of LONDONDERRY, and of Parts of Tyrone and Fermanagh, examined and described under the Authority of the Master-General and Board of Ordnance. By JE PORTLOCK, FRS &c.
Page xxxii - Geology," the conviction at which I had then arrived, after devoting some time to observation in the field, and to the study of the works of earlier writers, that the existing causes of change in the animate and inanimate world might be similar, not only in kind, but in degree, to those which have prevailed during many successive modifications of the earth's crust.
Page 350 - ... of yellow ochrey hydrous peroxide of iron. In some parts of the vein, the ankerite is intimately mixed with crystals and veinlets of yellowish spathose iron. The red ochrey iron ore occurs in minor veins and irregular masses dispersed in the ankerite. Some of these veins are two yards in thickness ; and the shapeless masses are often of much larger dimensions. Specular iron ore also occurs in small irregular veins, and in disseminated crystals and nests. At one part of the bank there appears...
Page xlv - Whewell has justly observed, that " mechanical power retains its amount, however much it be distributed through time and divested of the character of extraordinary violence,"* — a principle which should never be lost sight of when we contrast the effects of the historical with those of antecedent epochs. It is not the magnitude of the effects, however gigantic their proportions, which can inform us in the slightest degree whether the operation was sudden or gradual, insensible or paroxysmal.
Page 336 - Of the law which determines the extinction of races of highly organized beings, and whose effects through countless ages Palaeontology has in part revealed, we are as utterly ignorant as of that which governs the first appearance of the minutest living animalcule which the most powerful microscope enables us to descry : — both are veiled in inscrutable mystery, — the results only are within the scope of our finite comprehension. I have thus endeavoured to present a general idea of the facts and...
Page 16 - Jurassic strata, and still more with the palseozoic deposits, has been regarded by Dr. Boue', not without some probability, as the most ancient known effect of the influence of climate on the fauna of former worlds. In reality the most northerly point on the whole earth in which chalk has as yet been found is, according to Prof. Forchhammer's determination, in the vicinity of Thistedt in Jutland, not quite in 57 degrees of latitude, or in that of Aberdeen in Scotland, of Calmar, Mitau, Twer and Casan....
Page 244 - Strickland's paper the following remarks : — " (7) Ferruginous beds, consisting of coarse Oolite in the upper part, and of a very peculiar large-grained Oolite or Pisolite ('Pea-grit') in the lower. A few miles to the south the Pisolite disappears, and is replaced near Painswick and at Haresfield Hill by strata containing ferruginous oolitic grains in a brown paste.
Page xxxviii - English geologist who is old enough to remember when all the soft clays and loose sands overlying the chalk, some of them containing shells of species identical with those now living, were looked upon as very modern, and as the creations of yesterday, in comparison with the rocks of the higher Alps, it may well appear a startling proposition to learn that the clay of London was in the course of accumulation as marine mud at a time when the ocean still rolled its waves over the space now occupied...
Page 351 - ... band of slate and quartzite. Westward of the Acadia Mine the course of the vein over the high ground is marked by the colour of the soil, as far as Cook's Brook, about a mile distant. The outcrop of the ore was not exposed in this brook, but large fragments of specular ore have been found in its bed, and a .shaft, sunk on the course of the vein, has penetrated more than forty feet through yellow ochre containing a few rounded masses and irregular layers of ankerite. At this point the decomposition...