Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/63

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M U R M U R 51 into a definite order of succession, as the Secondary rocks of England had been made to tell their story by William Smith. For several years he continued to work vigorously in that region. The result was the establishment of the Silurian system, a definite section of the geological record, bringing into notice for the first time a remarkable series of formations, each replete with distinctive organic remains older than and very different from those of the other rocks of England. The full import of his discoveries 1 was not at first perceived ; but as years passed on the types of existence brought to light by him from the rocks of the border counties of England and Wales were ascertained to belong to a geological period of which there are recog nizable traces in almost all parts of the globe. Thus the term "Silurian," derived from the name of the old British tribe Silures, soon passed into the familiar vocabulary of geologists in every country. The establishment of the Silurian system was followed by that of the Devonian system, an investigation in which Sedgwick and Murchison were fellow-labourers, both in the south-west of England and in the Rhinelands. Soon after wards Murchison projected an important geological cam paign in Russia with the view of extending to that part of the Continent the classification he had succeeded in elaborating for the older rocks of western Europe. He was accompanied by De Verneuil and Keyserling, in con junction with whom he produced a magnificent work on Russia and the Ural Mountains. The publication of this monograph in 1845 completes the first and most active half of Murchison s scientific career. In 1846 he was knighted, and later in the same year he presided over the meeting of the British Association at Southampton. During the later years of his life a large part of his time was devoted to the affairs of the Royal Geographical Society, of which he became president. So constant and active were his exertions on behalf of geo graphical exploration that to a large section of the con temporary public he was known rather as a geographer than as a geologist. He particularly identified himself with the fortunes of David Livingstone in Africa, and did much to raise and keep alive the sympathy of his fellow- countrymen in the fate of that great explorer. The chief geological investigation of the last decade of his life was devoted to the Highlands of Scotland, where he suc ceeded in showing that the vast masses of crystalline schists, previously supposed to be part of what used to be termed the Primitive formations, were really not older than the Silurian period, for that underneath them lay beds of limestone and quartzite containing Lower Silurian fossils. By this important discovery he not only changed at once the accepted views of the structure of half a king dom but furnished a gigantic example of regional meta- morphism, the true significance of which in regard to theories of metamorphism is not yet adequately appreciated. In the year 1855 Murchison was appointed director- general of the geological survey and director of the Royal School of Mines and Geological Museum, Jermyn Street, London, in succession to Sir Henry de la Beche, who had been the first to hold these offices. Official routine now occupied much of his time, but he found opportunity for the Highland researches just alluded to, and also for pre paring successive editions of his work Siluria, which was meant to present the main features of the original Silurian System together with a digest of subsequent discoveries, particularly of those which showed the extension of the Silurian classification into other countries. His official position gave him still further opportunity for the exercise 1 The results of these researches were embodied in a massive quarto volume entitled The Silurian System (London, 1839). of those social functions for which he had always been distinguished, and which a considerable fortune inherited from near relatives on his mother s side enabled him to display on a greater scale. His house was one of the great centres where science, art, literature, politics, and social eminence were brought together in friendly inter course. In 1863 he was made a K.C.B., and three years later was raised to the dignity of a baronet. The learned societies of his own country bestowed their highest rewards upon him : the Royal Society gave him the Copley medal, the Geological Society its Wollaston medal, and the Royal Society of Edinburgh its Brisbane medal. There was hardly a foreign scientific society of note which had not his name enrolled among its honorary members. The French Academy of Sciences awarded to him the Prix Cuvier, and elected him one of its eight foreign members in succession to Faraday. One of the closing public acts of Murchison s life was the founding of a chair of geology and mineralogy in the university of Edinburgh, for which he gave the sum of 6000, an annual sum of 200 being likewise provided by a vote in parliament for the endowment of the pro fessorship. While the negotiations with the Government in regard to this subject were still in progress, Murchison was seized with a paralytic affection on 21st November 1870. At first his life was in danger, but he eventually rallied, and was able to see his friends, read, and take in terest in current affairs until the early autumn of the fol lowing year, when his malady began to make rapid progress. At last after a brief attack of bronchitis he died on 22d October 1871. The chief work for which Murchison will always hold a high place in the annals of geology is the investigation of the older Palaeozoic rocks, which culminated in the establishment and subse quent development of the Silurian system of formations. He added a new chapter to geological history, and one of peculiar interest, because it contains the story of almost the earliest appearance of living things upon this planet. From the year 1825, when his first paper was read, down to the year of his death lie continued to augment the literature of his favourite science with papers and memoirs. These, upwards of 150 in number, were published in the transactions of scientific societies at home and abroad. His Silu rian System, Russia and the Ural Mountains, and Siluria were the most voluminous and important of his independent works. As a careful original observer, a sympathetic and liberal friend of scientific progress, and a man of wealth and good social position Murchison enjoyed a peculiar eminence among the scientific men of his day, and occupied a place which none of his surviving compeers could wholly fill. See Murchison s Life by A. Geikie, 1875. (A. GE.) MURCIA, a maritime province of south-eastern Spain, is bounded on the E. and S. by Alicante and the Mediter ranean, on the W. by Almeria and Granada, and on the N. by Albacete, and has an area of 4478 square miles. The total extent of coast is about 75 miles ; from Cape Palos westwards to Villaricos Point (where Almeria begins) it is fringed by hills reaching their greatest elevation immediately to the east of Cartagena; northwards from Cape Palos to the Alicante boundary a low and sandy tongue of land encloses the shallow lagoon called Mar Menor. Eastward from the Mar Menor and northward from Cartagena stretches the plain known as El Campo de Cartagena, but the surface of the rest of the province is diversified by ranges of hills of which the general direction, connecting the mountains of Almeria and Granada with those of Alicante, is from south-west to north-east, and which reach their highest point (5150 feet) on the Sierra de Espuna, between the Mula and Sangonera valleys. They belong to the Nevada system, and their geology will be best treated in connexion with that of Spain generally ; they are rich in iron, copper, and argentiferous lead, and also yield large quantities of alum, sulphur, and salt petre ; and important mineral springs occur at Mula, Archena (hot sulphur), and Alhama (hot chalybeate).