Geology
2 of the 7 encyclopedias on this shelf carry an entry for Geology. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
the science which investigates the bygone history of the earth with the view of accounting for its present condition. It is the province of physical and political geography to describe what the earth now is, geology attempts to furnish the reason why. History. Though it was only during the 19th century that geology has started up into the vigor of manhood, yet its birth took place ages ago. Isolated geological observations or hypotheses occur abundantly in ancient literature. "As for the earth, out of it cometh bread; and under it is turned up as it were fire" (Job xxviii: 5); an anticipation of the Huttonian hypothesis. Egypt, according to Herodotus, is the gift of the Nile, that is, the river brought down the silt which constitutes the fertile soil of the delta and other parts of Lower Egypt. The best geologist of antiquity was the geographer Strabo, who lived in the 1st Modern geology began century A. D. with Werner, who was a professor in the School of Mines at Freiberg, in Saxony, in 1775. He believed that a series of universal formations had been deposited in succession from a chaotic fluid. Basalt was supposed to have had the same origin, but to this view various continental observers were opposed. Hutton published in 1788 his "Theory of the Earth," developed in a separate work in 1795. He assumed no causes but those now existing. He showed that geology and cosmogony were different. "In the economy of the world," he said, "he could find no trace of a beginning, no prospect of an end." He held basalt, granite, etc., . The Wernerians to be of igneous origin gin were called Neptunists, their opponents Vulcanists. In 1798 Cuvier published his "Fossil Bones," which gave a great impulse to palæontology. Forces or Causes in Operation. After inquirers had outgrown the belief in fossils produced by the plastic power of nature or all entombed simultaneously by the Noachian deluge, the belief was entertained that there had been a series of creations and catastrophies, the latter causing the universal destruction of all pre-existing species. The belief was also entertained that some external causes, say the forces producing earthquake and volcanic action, were more potent in former times than now. This Professor Huxley calls catastrophism, which he defines to be any form of geological speculation which, in order to account for these phenomena, supposes the operation of forces different in their nature or immeasurably different in power from those which are at present in action in the universe. The second school of geology is that called by Huxley uniformitarianism. This looks only to causes now in operation for the explanation of geological phenomena. Of this school Hutton was the founder, though it was Sir Charles Vol. IV-Cye-S Lyell that carried it forward to triumph. He showed the enormous changes which the causes now in operation are still producing, and that nearly every phenomenon, attributed to abnormally potent causes acting suddenly and briefly, could be produced by causes not more intense than those in action now, but operating through immense periods of bygone time. In his "Principles of Geology," he examines aqueous causes, the action of water acting in connection with tides, currents, etc., in seas, rivers, and lakes, also the action of ice in all its forms. Next he inquires into igneous causes, volcanoes, and earthquakes. Climate and organic life are also carefully investigated in the work. The doctrine of the third school of geologists is called by Professor Huxley evolutionism; it accepts nearly the whole of uniformitarianism, except the part referring to the development of organic life. In his later years Sir Charles Lyell became an evolutionist. See DARWINIAN THEORY: EVOLUTION. Geologic Time. Both the uniformitarian and the evolutionist believe that they may draw to any extent on what may be called the bank of time, which will be found "ready to discount any quantity of hypothetical paper." Sir William Thompson holds that any such drafts must be limited "within some such period as 100,000,000 years"; and another natural philosopher considers the time at call only about 60,000,000 years. Huxley believes the necessity for these limitations is not proved, though perhaps one, two, or three hundred millions of years might be enough to account for geological phenomena. With regard to the subdivision of the time, long or short, at the gelogists' command, the sedimentary strata ha ha having been laid down by water, the relative thickness of each stratum will measure the proportion of geologic time required for its deposition. Geologic strata. - The geological record is made up as follows, beginning with the five great PERIODS. 5. Quaternary. The age of man. 4. Cenozoic Period. Age of Mammals. 3. Mesozoic Period. Age of Reptiles. Age of Coal Plants. Age of Fishes. 2. Palæozoic Period. Age of Invertebrates. Lifeless and 1. Archæan Period. dawn of life. The following list gives the eras together with their dependent series and sub-divisions in descending order: 9. Quaternary or Post Tertiary: (3) Recent, (2) Champlain, (1) Glacial. 8. Tertiary Era: (4) Pliocene, (3) Miocene, (2) Oligocene, (1) Eocene. 7. Cretaceous Era: (4) Laramie, (3) Colorado, (2) Dakota, (1) Lower. 6. Jura-Trias: (b) Jurassic; (3) Purbeck, (2) Oölite, (1) Lias, (a) Triassic: (4) Rhætic, (3) Upper, (2) Middle, (1) Lower. 5. Carboniferous Era: (3) Permian, (2) Carboniferous, (1) Sub-carboniferous. 4. Devonian Era: (5) Catskill and Chemung, (4) Portage, (3) Hamilton, (2) Corniferous, (1) Oriskany. 3. Upper Silurian:. (3) Lower Helderberg, (2) Onondaga, (1) Niagara. 2. Lower Silurian: (3) Trenton, (2) Chazy, (1) Calciferous. 1. Cambrian. Eozoic (dawn of life), Azoic (lifeless). SUB-DIVISIONS. 9. Quaternary: Pleistocene; 8. Tertiary: English Crag, Upper Molasse, Rupelian and Tongrian of Belgium; 7. Cretaceous: Upper Chalk, Lower Chalk, Chalk Marl, Gault, Neocomian, Lower Greensand; 6. Jura-Trias: Wealden, Purbeck, Portland, Kimmeridge, Oxford Oölites, Lower or Bath Oölite, Lower beds, Dachstein beds; Alpine Trias, in Sandstein; 5. Carboniferous: Magnesian Limestone, Lower Red Sandstone, or Rothliegendes, Upper Coal Measures, Lower Coal Measures, Millstone Grit, Lower Carboniferous, Mountain Limestone; 4. Devonian: Old Red Sandstone- Catskill Red Sandstone, Chemung, Portage, Genesee Slate, Hamilton beds, Marcellus Shale, Upper Helderberg, Schoharie, Grit, Oriskany Sandstone; 3. Upper Silurian: Lower Helderberg, Onondaga Salt Group, Salina beds, Water Lime, Niagara Group, Wenlock Group, Clinton Group, Medina Sandstone (Upper Llandovery); 2. Lower Silurian: Hudson River beds, Cincinnati Group, Lower Llandovery, Utica Shales, Trenton Limestone, Caradoc and Bala Limestone, Black Shales, Armorican Grit, Gothlandian Calcareous Sandrock, Magnesian Limestone, Lower, Middle and Upper Cambrian; 1. Archæan: Laurentian, Huronian. Other Rocks. For these, see IGNEOUS Rocks. Fossils. For these, see FOSSIL: PA- LÆONTOLOGY. Applied Geology. - Geology applied to industrial or other practical purposes; as, for instance, to mining, drainage, railway tunneling, etc.
Aiton's Encyclopedia (1910)
. See many topics enumerated under GEOGRAPHY.