THE GEOLOGICAL MAGAZINE. No. XIX-JANUARY, 1866. GEOLOGICAL PROGRESS. No. 3.1 YEOLOGISTS assert that the operations of Nature, of which they are the expounders, are performed with a slowness that renders their progress almost imperceptible to actual observation. Geology itself, however, has, since its origin as a science-less than a century ago-grown with a rapidity and vigour the very opposite of the gradual movement of physical change. But as sudden and rapid growth is seldom altogether healthy, so the exuberance of vitality in the young science has ever and anon originated errors which have, at times, checked its career. Hasty generalizations, and loosely formed theories, advanced by would-be leaders of the science, have occasionally led their followers into wrong trains of thought, whereby they have failed to see the true bearing of facts brought before them, and have ceased, for a time, to advance their knowledge, on account of the incorrectness or insufficiency of their principles of explanation. One great means of correcting existing errors and preventing for the future the general adoption of others, is to maintain for the scientific world an easily accessible medium of discussion. In order, however, to render the discussion of any Geological topic useful, it must be based in the first instance upon accurately recorded observations; and as every year increases the number of observers, it also becomes important to enlarge the opportunities of preserving the results of their labours. The aim of the GEOLOGICAL MAGAZINE, since its commencement in 1864, has been to supply this need, and to supplement, as far as possible, the authoritative and old-established Journal of the Geological Society. But the GEOLOGICAL MAGAZINE has in fact a wider scope, since it is not limited to the sphere of any one society, but opens its pages to all Geologists, in which to record their observations and discoveries, and so promote the general progress of the science both at home and abroad. Let us look at one or two points of Geological Progress during the past year. 1 "Geological Progress," Nos. 1 and 2, appeared in the July and August Nos. of the GEOLOGICAL MAGAZINE, 1865, pp. 289 and 337. VOL. III-NO. XIX. 1 Dr. Holl's work in the Malvern District,' is a labour of value in which the discussion of the origin of certain rocks will not merely alter their place and name in our classification, but will aid in the reconstruction of our ideas of the extent and distribution of strata which are the very basement of our entire Geological series. In-like manner Messrs. Salter and Hicks, in a remote district of South Wales, have worked out the presence of rocks of at least an approximately similar antiquity, revealing to us a fauna hitherto almost unknown in Britain, and similar to, but not identical with, the Primordial Zone of Barrande; and for which the discoverers have proposed the new term "Menævian Group." The interesting question of the earliest-known forms of life remains much where it was left in 1864, the discussion at Birmingham having elicited no new facts to alter the conclusions arrived at by the generality of British and Canadian Geologists, neither has further investigation afforded any new forms. 8 6 Sir W. E. Logan, Mr. T. Sterry Hunt, Dr. Dawson, Dr. Carpenter, and Prof. Rupert Jones, have each published the results of their separate investigations of Eozoon Canadense. Dr. Carpenter finds no difficulty in placing Eozoon in the Nummuline series of Foraminifera, with certain resemblances to Calcarina. It is wonderful to find so very lowly an organism spreading out in these ancient seas, and forming masses as large as coral-reefs; but our astonishment becomes even greater, when we are assured by Messrs. Parker and Jones' that the Foraminifera of the present day, form no less than 95 per cent of the ooze covering the floor of the wide Atlantic ocean. The Chalk is doubtless also largely indebted to these humble foraminated shells; whilst in some of the older Tertiaries they play a more conspicuous part than any other organism-the Nummulitic formation often attaining a thickness of many thousand feet, and extending from the Alps to the Himalayas, and from Algeria to Caboul.10 In addition to the great palæontological value of Dr. Duncan's descriptions of West Indian and other Tertiary Corals, etc.," his papers possess a higher claim to notice, in the suggestions they offer us concerning the physical history of particular localities, and also as aids in explaining more general geological phenomena of the movements and distribution of life in past times, and the share of such past life in forming our present faunas. The power of Glaciers to excavate Lake-basins met with an ener 1 Quart. Journ. Geol. Soc., vol. xxi. p. 72. 2 Ibid., vol. xxi. p. 476, and present No. of GEOL, MAG. p. 27. 3 GEOLOGICAL MAGAZINE, vol. i. p. 225. 4 Quart. Journ. Geol. Soc., vol. xxi. p. 45. 5 Ibid., p. 67. 6 Ibid., p. 51 (Plates VI. and VII.) 7 Ibid., p. 59 (Plates VIII. and IX.), and Intellectual Observer, vol. vii. p. 278. 8 Popular Science Review, April, 1865. 9 Phil. Trans., 1865, pp. 325-341. 8 plates. 10 Lyell's Elements, 1865, 6th edition, p. 305. Quart. Journ. Geol. Soc., vol. xxi. pp. 1, and 349. getic opponent in the President of the Geological Society, Mr. W. J. Hamilton, who, in his Anniversary Address,' discussed adversely the views lately promulgated by his predecessor, Professor Ramsay, from the same chair. Professor Phillips' has also expressed his views and observations upon Ice-action, and the height to which it is possible for Glaciers to ascend by the continuous pressure of the mass above. But his examination of Wastwater, in Cumberland, led him to the conclusion that Ice would not have been effective in excavating its basin. The eminent Swiss Geologist, M. Desor, in his recently published work, "Der Gebirgsbau der Alpen," adds the weight of his name to the adverse party. He divides lake-basins into three classes, namely: 1, lakes situated in depressions between mountains, at right-angles to their general direction-to which class belong the Italian lakes; 2, lakes in the plain or on the borders of mountains, whose basins have been excavated by water; and 3, moraine-lakes, whose waters are dammed up at their outlet, as the Brienzer-See. Every thoughtful geologist must admit that Seas and Rivers, Frost and Snow, Rain and Ice, have all shared in the labour of fashioning the present surface of our earth-nay, more, are doing so to-day— each performing its own portion of the task, and leaving (as Mr. J. F. Campbell has admirably shown) its "tool-marks" to testify to the engine used. Again, though many metamorphic rocks, formerly attributed to Igneous origin, are now known to be in reality sedimentary deposits, crushed and altered by pressure, beneath superincumbent strata of more recent date; we have still left, in all parts of the world, evidences of upheaval by volcanic action, accompanied by deposits of truly erupted or intruded material, the nature of which cannot be explained by shrinkage of the mass, or crumplings of the crust by lateral pressure, though each of these causes has produced its effect. Volcanic outlets like the Sumatran and Javan range, which comprise no less than 109 lofty fire-emitting mountains, or like that of Central America (lately visited by Professor K. von Seebach, of Göttingen, who examined upwards of 30 craters, nearly all of which were active) are slight surface-indications of what must be the pressure, and consequently the heat, at great depth beneath the crust of our globe. We trust that physical geologists will this year agree to divide the burden of work more equitably between Seas, Rivers, and Ice, Fire and Rain, Frost and Snow, taking into careful consideration the relative powers of each agent (as seen at work to-day) in having produced like results, but on a larger scale perhaps, in the past. (To be continued.) 1 Quart. Journ. Geol. Soc., vol. xxi. p. lxxxvii., Anniversary Address. GEOL. MAG., vol. ii. p. 513. Frost and Fire, etc. By a Traveller. Edinburgh: Edmonston and Douglas. 1865. 2 vols. 8vo. pp. 1015, and 117 illustrations. Scrope on Volcanoes, 2nd edition, 1862, p. 12. |