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Seite 163 - Report of the Proceedings of the Geological and Polytechnic Society of the West Riding of Yorkshire, 1863 — 4.
Seite 157 - On the Claims of the Gigantic Irish Deer to be considered as contemporary with Man,'' there is a long discussion on this subject, from which I extract the following statements, which I have not verified personally : — The leg of a Megaceros, with a portion of the tendons, skin, and hair on it, was found in the county of Wexford, on the estate of H. Grogan Morgan, Esq., at Johnstown Castle. This specimen was sent to the RoyalDublin Society, and was exhibited by Mr. Peall, Professor of Veterinary...
Seite 81 - ... primitive rocks. * The question here arises, whether in the absence of organic remains, or of stratigraphical evidence, there exists any means of determining, even approximately, the geological age of a given series of crystalline stratified rocks; in other words, whether the chemical conditions which have presided over the formation of sedimentary rocks have so far varied in the course of ages, as to impress upon these rocks marked chemical and mineralogical differences.
Seite 143 - The remains were disposed in such a manner as to prevent the possibility of ascertaining the exact component parts of each skeleton; in some places portions were found removed many yards from others, and in no instance were two bones found lying close to each other. Their position also was singular; in one place two heads were found, with the antlers entwined in each other, and immediately under them a large blade-bone; in another, a very large head was discovered, and although a most diligent search...
Seite 85 - ... baths. From this he was led to suppose that the metamorphism of great regions might have been effected by hot springs, which, rising along certain lines of dislocation, and thence spreading laterally, might produce alteration in strata near to the surface, while those beneath would in some cases escape change. J This ingenious hypothesis may serve in some cases to meet the difficulty pointed out by Naumann ; but while it is un* "Proc. Royal Soc. London," May 7, 1857, and "Philos. Mag.
Seite 90 - Laurentian rocks of the Adirondack Mountains, of which, according to Emmons, they form the highest summits. In the third series, which we have referred to the Lower Silurian age, the gneiss is...
Seite 85 - These observations were the complement of my own, and both together showed the agency of heated alkaline waters to be sufficient to effect the metamorphism of sediments by the two modes already mentioned — namely, by molecular changes, and by chemical reactions. Following upon this, Daubree observed that the thermal alkaline spring of Plombieres, with a temperature of 160° F. had, in the course of centuries, given rise to the formation of zeolites, and other crystalline silicated minerals, among...
Seite 86 - ... thousands of square miles. On the other hand, the study of the origin and distribution of mineral springs shows that alkaline waters, whose action in metamorphism I first pointed out, and whose efficient agency...
Seite 85 - ... beneath : there being no apparent transition between the two. This, taken in connection with the well-known, fact that in many cases the intrusion of igneous rocks causes no apparent change in the adjacent unaltered sediments, shows that heat and moisture are not the only conditions of metamorphism.
Seite 49 - Marine denudation is effective only about the sea level, and along the margin of the land. It acts with a broad horizontal movement, tending to plane down the land to its own level. If the land be long stationary, it produces long vertical cliffs about its margin ; if the land rise slowly and equally, it forms gentle slopes upon it.