Popular Science Monthly/Volume 43/June 1893/Sketch of Sir Archibald Geikie

From Wikisource
Jump to: navigation, search
PSM V43 D156 Archibald Geikie.jpg


THE most prominent features in Sir Archibald Geikie's geological work are his studies of the effects of volcanic force, beginning in Scotland and extending to many countries; and his explanations of the fundamental part which geological processes have played in shaping the topographical features of the land, and in the origin of natural scenery.

Prof. Geikie was born in Edinburgh in 1835; was educated at the high school and the university in that city; was appointed an assistant on the Geological Survey of Scotland in 1855; acquitted himself so well in that capacity that when the Scottish branch of the survey was made a separate establishment in 1867, Sir Roderick Murchison appointed him its director. In December, 1870, he was appointed to the new professorship in the University of Edinburgh of Geology and Mineralogy, founded by Sir Roderick Murchison, with a concurrent endowment by the crown. He held this position till the beginning of 1881, when he resigned it, to take the place of Sir Andrew C. Ramsay as Director-General of the Geological Survey of the United Kingdom, and Director of the Museum of Practical Geology in London.

The published record of Prof. Geikie's life relates exclusively to his investigations, papers, addresses, and books on subjects relating to geology. In this field he has labored with unceasing diligence, and to it he seems to have devoted the whole energy of his active career. Complicated problems presented themselves to him when he entered upon the surveys, of which he was called upon to work out the solutions. One of the first to attract his attention was the relation of the crystalline rocks of the Highlands to the Silurian strata on which they rest, which Murchison had accepted as normal; an assumption from which logically followed the hypothesis that these gneisses were altered sediments. Mr. Geikie gradually became dissatisfied with this view, and commissioned two assistants to review the fields in which the most decisive evidence was to be obtained, instructing them "to divest themselves of any prepossession in favor of published views, and to map existing facts in entire disregard of theory." From the evidence afforded by this survey, Murchison's view was proved to be a mistaken one; and for it was substituted the theory that the elevation of the mountains and the metamorphism of the gneisses were the effect of enormous pressure resulting in the folding and breaking of the whole border of the dry land. The mountains have been reduced to their present shape by denudation, by which also much of the evidence of plication has been washed away, while the remains of the disturbed rocks occupy the position which, suggested Murchison's view. The displacements were accompanied by modifications of the rocks, of which Geikie wrote that "in exchange for this (Murchison's) abandoned belief we are presented with startling new evidence of original metamorphism on a colossal scale, and are admitted some way into the secret of the processes whereby it has been produced."

Sir Archibald Geikie's chief geological work, according to the estimate of Nature, seems to be his exhaustive review of the volcanic history of the British Isles. The northwestern part of Great Britain is marked, like the Snake River region in our own country, by the evidences of the outpouring over the land of immense sheets of lava, which in the present instance took place in Tertiary times. Sir Archibald made it his task in the investigation of this phenomenon "to discern the site of the centers of eruption, and determine the old chimneys, the remnants of which give a glimpse into the lowest parts of ascending lavas; to discriminate the volcanic necks, the intrusive sheets and dikes, the bedded lavas and the tuffs." Evidences of still earlier volcanic activity were also found in the Old Red Sandstone of Scotland, and in the oldest formations of England and Wales. In order to prepare himself more thoroughly for the investigation of this phenomenon, Mr. Geikie traveled over much of Europe, from northern Norway to the Lipari Islands; then came over to Canada and the United States, and followed the course of our geological surveys, particularly in the Western States and Territories and the lava-covered regions. In another department of the same investigation he gave more attention to petrological studies than any Englishman had done before him. Besides giving rise to many valuable memoirs relating directly to what he had seen and observed, these studies contributed greatly to the enlargement of Prof. Geikie's views and to the increase of the breadth of his work; and some of their results may be seen in the greater richness of illustration apparent in his subsequent writings. Their mature fruit is presented as a whole in his presidential addresses of 1891 and 1892. He was especially interested, they being exactly in the line of his principal study, in the lava beds of Snake River; and in his essay on the Lava Fields of Northwestern Europe refers to them as the site which first enabled him to realize the conditions of volcanic action described by Richtofen—the emission of vast floods of lava without formation of cones and craters—and, without acquiescing in all that author's theoretical conclusions, to judge of the reality of the distinction "which he rightly drew" between massive eruptions and ordinary volcanoes with cones and craters.

We have referred to Prof. Geikie's work in tracing the origin of the present shaping of land surfaces and of natural scenery to its geological factors as constituting one of his special titles to fame. To his aptitude in this application Nature largely ascribes the success of his more popular works, which, it says, "will be easily understood if we remember that in Sir Archibald's works the traditional barrenness of geology is always smoothed and adorned by a deep and intense feeling for Nature. Nobody has done more than he to associate geological science with the appreciation of scenery." Mr. G. K. Gilbert, in a review of his TextBook of Geology, remarks as a single departure in the volume the elevation of physiographical geology to the rank of a major division. "The same title, it is true, has been placed by Dana at the head of a primary division of the subject, but it was used by him in a different sense. With Dana it is a synonym for physical geology; with Geikie it is 'that branch of geological inquiry which deals with the evolution of the existing contours of the dry land.' So far as the subject has had place in earlier treatises, it has been regarded as a subdivision of dynamical geology, and the classification which placed it there was certainly logical. In dynamical geology, as formulated by Geikie, the changes which have their origin beneath the surface of the earth (volcanic action, upheaval, and metamorphism) and the changes which belong exclusively to the surface (denudation and deposition) are separately treated. In physiographical geology the conjoint action of these factors of change is considered with reference to its topographical results. Starting from geological agencies as data, we may proceed in one direction to the development of geological history, or in another direction to the explanation of terrestrial scenery and topography, and if the development of the earth's history is the peculiar theme of geology, it follows that the explanation of topography, or physiographical geology, is of the nature of an incidental result—a sort of corollary to dynamical geology. The systematic rank assigned to it by Geikie is an explicit recognition of what has long been implicitly admitted—that geology is concerned quite as really with the explanation of the existing features of the earth as with its past history."

The subject was first formally presented from this point of view in the Lectures on the Scenery of Scotland viewed in Connection with its Physical Geology, which were delivered in 1865. At this time, as Mr. A. H. Green remarks in his review of a new edition of the lectures in 1887, the controversy respecting Hutton's theory of denudation as the main and most efficient agency in shaping the earth's surface was at its height. The author acknowledged in the preface to his second edition that his views when first published ran directly counter to the prevailing impressions on the subject; but now, after a lapse of twenty-two years, they were accepted as part of the general stock of geological knowledge. "How largely," Mr. Green says, "this result is due to his own steady and powerful advocacy all geologists are aware; but he gracefully reminds us that we also owe much to the labors of those American geologists who have found in the Western Territories such convincing instances of the work of denudation in shaping the surface." The first part of the book, comprising the lectures, deals with land-sculpture in general, and describes the working of Nature's sculpturing tools. The reader is then taken in succession to the different characteristic regions in the country and shown in detail, with much wealth of illustration, how the hills and valleys and salient features have been wrought out. The subject could very well be treated in such a manner as to make the presentation of it formal and dry in the extreme; but, says Mr. Green, the author "knows and loves his fatherland too well to look upon it merely as the object of geological research. Legend and history, old ballads and modern poetry, have all been pressed into his service, and he interweaves into his narrative allusion and quotation in a way that enlivens even the most technical parts of the volume. The chapter on The Influence of the Physical Features of Scotland upon the People shows well what a vast amount of human interest attaches even to so special a science as geology."

Prof. Geikie himself predicted in an address before the Geological Society of Edinburgh, in 1873, for the future of his theory: "Of one thing I feel surely confident: When the din of strife has ceased and men come to weigh opinions in the dispassionate light of history, the profound influence of the Huttonian doctrines of the present time on the future course of geology will be abundantly recognized. By their guidance it will be possible to reconstruct the physical geography of the continents in successive ages back into some of the earliest periods of geological history."

Prof. Geikie's theory is further elaborated and applied in his five lectures, delivered at the Royal Institution, in 1884, on The Origin of the Scenery of the British Isles. In these lectures the author held that "the present surface of Britain is the result of long, complicated processes in which underground movements, though sometimes potent, have only operated occasionally, while superficial erosion has been continuous so long as any land has remained above the sea. The order of appearance of the existing features is not necessarily that of the chronological sequence of the rocks. The oldest formations have all been buried under later accumulations, and their re-emergence at the surface has only been brought about after enormous denudation." The lectures conclude with an indication of the connection between the scenery of a country and the history and temperament of its people. This subject was considered from four points of view, the influence of landscape and geological structure being traced in the distribution of races, national history, industrial and commercial progress, and national temperament and character. Prof. Geikie found in the United States an emphatic confirmation of his theory in one of the most impressive features of our geology, which he records, in 1887, in a review of Newberry and Macomb's Survey of the Upper Colorado. "The whole of this Colorado basin or plateau is justly regarded as the most magnificent example on the face of the globe of how much the land may have its features altered by the action of running water."

The method based upon this theory prevails in Prof. Geikie's Physical Geology, which is described by Dr. Jukes as "an example of the treatment of geographical questions from the point of view of the geologist." The author is actuated, the reviewer continues, "by the conviction of the necessity for a broader and more vivid presentation of the action and reaction upon one another of the various forces acting and reacting upon the surface of the globe than is usually found in works on physical geography, in order to convey a just idea of the character and significance of the features which it presents."

The subject is again presented in the presidential address at the Edinburgh meeting of the British Association in 1892, the special topic of which was the commemoration of the centenary of Hutton's theory and uniformitarianism, and in which special stress is laid on Hutton and Playfair's recognition of the fact that existing inequalities in topographical detail "are only varying and local accidents in the progress of the one great process of the degradation of the land."

This breadth of view concerning the methods and purposes of geological study marks those of the author's addresses of which that was the principal subject. In the opening lecture before the class in geology of the University of Edinburgh, delivered in 1871, he advises his hearers, "Let us turn from the lessons of the lecture-room to the lessons of the crags and ravines, appealing constantly to Nature for the explanation and verification of what is taught."

The introduction to his Class Book of Geology, published in 1886, concludes with the words: "Geology is essentially a science of observation. The facts with which it deals should, as far as possible, be verified by our own personal examination. We should lose no opportunity of seeing with our own eyes the actual progress of the changes which it investigates, and the proofs which it adduces of similar changes in the far past. To do this will lead us to the banks of rivers and lakes, and to the shores of the sea. We can hardly take any country walk, indeed, in which, with duly observant eye, we may not detect either some geological operation in actual progress, or the evidence of one which has now been completed. Having learned what to look for and how to interpret it when seen, we are as it were gifted with a new sense. Every landscape comes to possess a fresh interest and charm, for we carry about with us everywhere an added power of enjoyment, whether the scenery has been long familiar or presents itself for the first time. I would therefore seek at the outset to impress upon those who propose to read the following pages that one of the main objects with which this book is written is to foster a habit of observation and to serve as a guide to what they are themselves to look for, rather than merely to relate what has been seen and determined by others." At the very outset in this work, geology is regarded, "not as an amusement for the collector and a means of learning where he will get pretty and curious objects for his cabinet; not as a field where the ingenuity or perversity of the classifying mind may delight itself with grouping natural products as reason prompts; not in any other of those limited aspects beyond which it is feared the wisdom of some geologists never reaches; but as a history—the history of the earth in ages long gone by."

Believing that no branch of the study should be overlooked, we find him lamenting, in 1871, that while in all that relates to stratigraphic geology the British had kept ahead of other nations, they had allowed petrography, or the study of rock species, to fall into disuse. Matters had improved, partly perhaps under his own influence, in 1880, when, writing of the Mineralogical Society of Great Britain, he remarked upon a revival of interest in mineralogy, which had before been neglected for fossil-hunting.

In one of the reviews of Prof. Geikie's Science Primer of Geology, in 1874, a curious omission is remarked, in that the author had not referred to Darwin's theory of coral islands as a "proof that a part of the crust of the earth has sunk down"—the reviewer suggesting that to lead pupils up to this theory, and then test it as Darwin had tested it, was "an excellent exercise in that peculiar kind of reasoning about past causation which is of the essence of geology." Prof. Geikie appears to have built, as the saying is, better than he knew; for in 1884 he confessed himself reluctantly compelled, in view of Mr. Murray's observations in the Challenger Expedition, to admit that Mr. Darwin's theory could no longer be accepted as a complete solution of the problem of coral reefs.

Prof. Geikie has long taken an intense interest in the American geological surveys, and has followed them up with the closest attention for many years; and his notices of their reports and summaries of their results constitute a very considerable part of his frequent contributions to Nature. He was fully impressed with the magnitude and extent of the geological phenomena of the United States, and of the vahie of the study of them for the contributions it affords to our general knowledge of the subject and the explanations it furnishes of phenomena in other countries.

Writing on the subject in 1875, he said the United States had certainly done noble work in the exploration and mapping of its vast empire. Having spoken commendatorily of the style in which the reports were prepared and distributed, he added, "But whatever be their external guise, these narratives are pervaded by an earnestness and enthusiasm, a consciousness of the magnitude of the scale on which the phenomena have been produced, and yet a sustained style of quiet description, which can not but strike the reader." In reviewing Hayden's Report at the end of 1883, he ascribes a singular fascination to American geology. "Its features are as a whole so massive and colossal, their infinite detail so subordinated to breadth of effect, their presentation of the great elements of geological structure so grand, yet so simple and so clearly legible, that they may serve as types for elucidating the rest of the world. The progress of sound geology would assuredly have been more rapid had the science made its first start in the far West of America, rather than among the crumpled and broken rocks of western Europe. Truths that have been gained on this side of the Atlantic by the laborious gathering together of a broken chain of evidence would have proclaimed themselves from thousands of plateaux, cañons, and mountain ranges, in language too plain to be mistaken. No European geologist can visit these Western regions without realizing more or less distinctly what an amount of time has been wasted over questions about which there should never have been any discussion at all. This impression is renewed by every new geological memoir which brings to us fresh revelations of the scenery and structure of the Western Territories."

On the occasion of his appointment as Director-General of the Geological Survey of Great Britain and Ireland, Prof. Geikie was presented in March, 1882, by past and present students of the geology class in the University of Edinburgh with an illuminated address, recording their sense of loss on his leaving the university; referring to the distinguished services he had rendered the science; recognizing the signal success with which he had maintained the reputation of the Scottish school of geology, and of Edinburgh; and expressing the sympathy and affection with which they regarded him. Prof. Geikie responded in similar spirit, and said that he believed he was the first in Scotland, if not in Britain, to organize a practical class for the study of mineralogy and the microscopic investigation of rocks. He had tried always to make the cultivation of field geology a prominent part of the work of the class; and some of their pleasantest associations had been among the glens of the Highlands and the hills and shores of the Lowlands.

Prof. Geikie is a prolific writer on all subjects relating to geology. When ho was appointed in 1871 to the chair in Edinburgh he had the whole department to organize—a difficult task, but also an educating one—and to that, says Nature, we are indebted for the undisputed superiority which he has displayed in his Text Book, as well as in his other educational writings, "such as the Class Book, a very model of clearness, whereby it has been once more demonstrated that those only are qualified for writing elementary books who are in the fullest possession of the whole matter." Likewise he is the author of small books or primers on Physical Geology and Physical Geography, of which some hundreds of thousands of copies have been sold, and which have been translated into most European languages, as well as several Asiatic tongues. He is also author of numerous memoirs in the Quarterly Journal of the Geological Society, the Transactions of the Royal Society of Edinburgh, the memoirs of the Geological Survey, the Quarterly and North British Reviews, Nature, etc.; of the Story of a Boulder, 1858; in conjunction with the late Dr. George Wilson, of The Life of Prof. Edward Forbes, 1861; of the Phenomena of the Glacial Drift of Scotland, 1863; The Scenery of Scotland viewed in Connection with its Physical Geology, 1865, and a new edition, largely rewritten, in 1887; in conjunction with the late J. B. Jukes, of a Student's Manual of Geology, 1871; of the Science Primers of Physical Geography, and Geology, 1873; Memoir of Sir Roderick I. Murchison, with notices of his Scientific Contemporaries, and of the Rise and Progress of Palæozoic Geology in Britain, 2 vols., 1874; of the Geological Map of Scotland, 1876; of the Class Book of Physical Geography, 1877; of Outlines of Field Geology, 1879; of Geological Sketches at Home and Abroad, 1882; of A Text-Book of Geology, 1882; of A Class Book of Geology, 1886. Prof. Geikie was associated with Sir Roderick Murchison, in the Scottish Highlands, in the preparation of a memoir of that district, and of a new Geological Map of Scotland, both published in 1861. Ho was elected to the Royal Society before reaching the age of thirty years, and is now its foreign secretary. He is past President of the Geological Society. He received the Murchison Medal of the Geological Society in 1881, and has been twice awarded the McDougal Brisbane medal of the Royal Society of Edinburgh. He is an associate of the Berlin Academy, of the Royal Society of Sciences at Göttingen, of the Imperial Leopold Caroline Academy, of the Imperial Society of Naturalists at Moscow, and a correspondent of the French Academy of Sciences.