Journal, Том 14 |
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animal arborescent markings Beasley Birkenhead Blundellsands Bootle boulder C. F. Webb canines carbon Caves Chair character Cheirotherian footprints Cheirotherium Chirosaurus Clague claws colour Committees Cornwall Council crystals digits Eocene Eozoon exhibited extinct felspar FIELD MEETING footprint bed fore and hind fore feet fossil Free Library Genus Geological Society gneiss granite H. T. White Howarth humus or soil ichnites illustrated impressions inches incisors J. H. JONES Keuper known Labyrinthodont Landscape Marble large number length of manus Library on Monday limestone Liverpool London Melbourne metamorphic mica Microscopical minerals Miocene molars Museum Natural History Naturalists ORDINARY MEETING orthoclase Owen Oxton Paper was read PATERSON peat Perissodactyls PLATE Potter pre-molars President Pritchard proboscidians Professor Miall quartz quartz and mica Rhyncosaurus Road rock Runcorn sandstone saurian SCOTT-WALKER showing Slab species specimens stone Stoneycroft Storeton Storeton Quarry stortonensis Street T. R. Connell teeth Thompson toes tourmaline Triassic typical granite WILLIAM BROWN STREET
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Стр. 30 - ... explanation to account for the formation of the rock, and maintains that its peculiar characters are due to interbedded layers of vegetable matter, which decomposed and evolved carbonicacid gas and marsh-gas. This decomposition continued while several inches of new sediment were laid down, the result being that arborescent markings were produced along the lines taken by the escaping bubbles...
Стр. 25 - ... a thoroughly granitic character. Between gneiss and granite there is no difference in mineralogical composition ; in the one rock the minerals are arranged in folia, in the other they have no definite arrangement. Gneiss might be called a foliated granite ; granite might be termed a non-foliated gneiss. The two rocks may be observed to graduate into each other.
Стр. 18 - The. older geologists regarded granite as the primitive rock of the earth's crust, forming the floor of all stratified deposits and the nucleus of mountain chains. Such a view, however, has been long exploded. It is known indeed that granite, so far from being in all cases an original rock, may be of almost any geological age. Some is undoubtedly as old as the Silurian period, whilo cither granites are certainly as young as the Tertiary rocks, and perhaps of even more recent date.
Стр. 19 - A portion of this mass, undergoing extreme alteration, may so completely lose all trace of its original fissile structure as to become amorphous crystalline granite, some of which may even be thrust as veins into the less highly changed parts above and around.
Стр. 21 - He instanced especially several gadolinites, orthites, and allanites, which cannot endure a higher ternperature than a dull-red heat without altering their physical characters ; and he concluded that granite, though it may have possessed a high temperature, cannot "have solidified from simple igneous fusion. We may conclude, therefore, that the manner in which rocks have...
Стр. 14 - ... investigations on Labyrinthodonts, chiefly from a biological point of view, and though he apparently accepts Owen's correlation — since he terms it " successful " (p. 67) — he shows very clearly that the Cheirotherium impressions do not coincide with the normal type of Labyrinthodon. For the " handfooted kind, where the hind limbs by reason of their greatly increased size depart from the central type,
Стр. 19 - Fundamentally, indeed, . igneous and metamorphic granite seem to be due only to different modifications of the same subterranean processes. A mass of originally sedimentary rocks may be depressed to a depth of several thousand feet within the earth's crust, subjected there to vast pressure and considerable heat in presence of interstitial water or steam, and may thus be metamorphosed into crystalline schists.
Стр. 6 - By OSMUND W. JEFFS. EVERY geologist is familiar with the name of Storeton Quarry, which may fitly be termed the " home of the Cheirotherium," celebrated as being the scene of the earliest discovery in England of the fossil footprints, first described by Messrs. John Cunningham and James Yates in 1839. Fifty years...
Стр. 18 - Hull, and other islands in the Inner Hebrides. As Mr Jukes suggested many years ago, granite or granitoid masses may lie at the roots of volcanoes, and may be the source whence the more silicated lavas, such as trachyte and liparite, proceed.3 That some granite...
Стр. 25 - The sarcophagus of the Duke of Wellington in St. Paul's Cathedral is wrought out of a splendid block of this granite.