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James Geikie
Chapter X. The Glacial Problem before James Geikie


In 1861, at the age of twenty-two, James Geikie, as stated in Chapter II., became an officer of the Geological Survey and determined to devote his life to scientific work.

For seventy years, ever since the time of the great discussions about the theories of Hutton and Playfair in the closing days of the eighteenth century, the inhabitants of Edinburgh had been keenly alive to the attractions of geological speculation. These older controversies had died down, and the science was gradually establishing itself on a broad basis of recorded facts and observations. It was not yet included among the subjects which had a place of honour in the University curriculum, though the professors of natural history since the time of Jameson had delivered lectures on geology (or geognosy as it was often called). Prof. Edward Forbes, who succeeded Jameson, and Prof. Fleming (of the Theological College) were both accomplished geologists. The Edinburgh Geological Society had been established in 1834, and though it did not as yet publish Transactions, it included many active geologists in the list of its members. Geology, with its mixture of open-air activities, hard facts of observation, and rich opportunities for speculative controversy, has always possessed an attraction for Scotsmen, and many of them have excelled in it. In the Scottish capital in the early sixties the burly figure of Hugh Miller was very well known. His writings, with their curious mixture of geological and theological matters, of fossil fishes and final causes, were very widely read at that time, and the sad tragedy of his death, the result of an overworked brain, was fresh in the memory of all.

A man of very different qualities, but a brilliant and thoroughly reliable geologist, who held a high place in the intellectual life of Edinburgh, was Charles Maclaren, one of the founders and for many years the editor of the Scotsman newspaper. His special field of work was the geology of the district around the Firth of Forth, a region filled with the most striking examples of geological structure and the effects of geological processes. Maclaren was constantly exploring the phenomena of this neighbourhood, and the results of his observations appeared regularly as articles in the Scotsman. No doubt this kept the science prominently before the public; few newspapers at the present time would venture to print columns of exact and rather technical description of the geological features of the district in which they are published. Maclaren died in August 1866, the year in which a second and much enlarged edition of his volume on the Geology of Fife and the Lothians was published. In the same year the Transactions of the Edinburgh Geological Society began to appear, but the Royal Physical Society, a successor of the Wernerian Society, had for several years been issuing Proceedings. Archibald Geikie had read a paper on the Geology of Strath in Skye to the Edinburgh Geological Society in 1853, and among the geologists of note who attended the meetings were Rose, Dr Page, Prof. Foster Heddle, and Dr Hunter of Carluke. Dr Page, afterwards Professor of Geology at Newcastle-on-Tyne, was a well-known popular lecturer on geology, and did a good deal to keep alive an interest in the science.

In later years James Geikie often acknowledged his indebtedness to Prof. George Wilson, and the stimulus he had received from him when a young man bent on scientific studies. Wilson was Professor of Technology in Edinburgh University, a subject no longer included in the University curriculum. It seems to have comprised parts of dynamics, mechanical engineering and applied chemistry. Wilson was a man of great personal charm, exceedingly well informed, and always willing to help young students along the path of learning. He was interested in geology also, and undertook to write the life of Edward Forbes, but finished only the first six chapters, and the work was ultimately completed by Archibald Geikie.

Although James Geikie was always a great reader, it is not likely that he had more than an elementary knowledge of geology when he joined the Survey in 1861. Trained geologists, however, in those days were much less common than they are now, and the Survey was prepared to enrol men who had a good general education and showed special inclination and aptitude for this line of work. Careful personal selection must have been exercised, for many of those who then joined its ranks rose subsequently to high eminence in science. In field geology no better training could have been given than was adopted for these young men. They were sent out day by day with surveyors who had acquired a knowledge of field work, and were inspected regularly by experienced geologists, who corrected their errors and helped to solve their difficulties. As already noted in Part I. (see p. 20), his first work was the addition of drift lines to the solid maps of parts of Fife and the Lothians, and the drifts of the low grounds of Central Scotland remained to the close of his life the subject which interested him above all others, and with which he had the fullest acquaintance in the field..

When Geikie began to map both the solid and drift geology of a hitherto unsurveyed district, he was sent to Ayrshire and West Lanarkshire, where he undertook the survey of a large area stretching from Eaglesham southwards to New Cumnock. His brother was mapping, or had already mapped,. a broad "strip extending inwards from the coast-line and reaching from near Largs in the north to Dailly in the south, while to the east of him was Peach engaged in the survey of Southern Lanarkshire. In those days a fairly large area (several hundred square miles) was assigned to each geologist. The whole district had to be very carefully examined and the results recorded on topographical maps on the scale of six inches to a mile. Each geologist was expected to make a complete examination of his ground and to note all the particulars regarding it. Petrology was as yet in its infancy, and no very minute classification of volcanic rocks was to be expected; but the glacial geology and economic geology were to be carefully investigated and fossil localities noted, though, for the purpose of collecting fossils, the assistance of special officers was provided. The determination of all fossils requiring critical skill was in the hands of the Survey palaeontologists. Each geologist surveyed from a hundred to a hundred and fifty miles in a field season, which, allowing for holidays, amounted to seven or eight months, and to do this required regular hard work, much strenuous walking, and the power of concentrating on the general features, and not allowing one's attention to be absorbed by inconsequent details.

James Geikie seems to have had no difficulty whatever in picking up the essentials of field geology. He was very diligent and had sufficient physical strength for his work. In time he became a great walker, thinking nothing of covering fifty miles in a day. The open-air life suited him perfectly. He had one of the gifts most valuable to a field-geologist, sometimes described as "an eye for the country," the faculty of interpreting

the geological meanings that underlie surface features. Although never a professed palaeontologist he had a working knowledge of Carboniferous fossils, and he was always a keen and critical observer of rocks both in a fresh and in a weathered condition. His early maps, judged even by the standards of the present day, were astonishingly good, and always give the impression that he went thoroughly into the evidence so far as it was available. He was cautious and thorough, and as a result of this his maps show very few deletions due to changes of opinion as fuller information was acquired during the progress of his work. From the first he exhibited great ability as a draughtsman, and his maps and sections are not only very clear, well-proportioned, and pleasing to the eye, but show also an individuality which arose from natural gifts, and was not acquired by copying models.

Although at that time geologists on the Survey were not moved about the country so frequently as is now the case, but settled down for several seasons in a well-defined area, James Geikie had no reason to complain of a lack of variety in the ground allotted to him. His early stations in Fife and Kinross included stratified and igneous rocks of Old Red Sandstone and of Carboniferous Age, and in Peeblesshire he made acquaintance with Silurian rocks, which at that time were still very imperfectly understood, and presented many difficult problems then unsolved. It was in Ayrshire, however, that his powers most fully displayed themselves, and the long period of field work in that county from 1865 to 1872 undoubtedly saw the development of his abilities as a field-geologist. In after years many of the best illustrations both of structural geology and of glacial geology that enlivened his books and his lectures were culled from the note-books in which he constantly recorded the results of his observations in that field. From his letters it seems that he disliked the coalfield geology, which necessitated the examination of mining plans, frequent attendance at colliery engineers' offices, and great absorption in details which are of little general importance. But no one would have suspected this from his. field maps, which, if we remember how rapidly his work was done, show much detail of underground structures taken from colliery plans.

In Ayrshire he had for colleagues Sir Archibald Geikie and Dr Peach; one of these was ultimately to select volcanic geology as his province, while the other attained great eminence as a palaeontologist. Already James Geikie was absorbed in glacial geology; and each of the trio of geologists, though doing ostensibly the same work, had already chosen the special line of investigation in which he was ultimately to become a master. He had a great affection, too, for the warm-hearted, hospitable people of the west of Scotland, and in "braid Scots" used to relate many humorous episodes in which the sturdy farmers and "sma' lairds" displayed their pawky humour. No full or adequate account of the work he did in Ayrshire in these years has ever been published.

The short descriptions of sheets 22, 23, and 19, published by the Geological Survey, were in large part written by James Geikie, but, owing to the necessities of official publication entailing great brevity, they contain merely an outline of his main conclusions. The geologists who revised that ground forty years after the original survey are unanimous in regretting that more adequate description of the evidence which James Geikie had collected was not placed before the public.

After leaving Ayrshire he was transferred to Kelso, and subsequently to the district ranging from Perth to Dunkeld. From a geological point of view this ground was considerably less varied; but as his note-books show, he was by this time deeply absorbed in glacial and Pleistocene geology, and every scrap of information regarding the latest stages in the physical history of Scotland was most carefully recorded and its importance weighed. Many of the conclusions he had already arrived at in Ayrshire were confirmed by fresh evidence in these years. And the estuary of the Tay, with its rich succession of late-glacial and post-glacial accumulations, became of great importance in his interpretation of the "glacial succession," a subject to which the remainder of his life was devoted more than to any other.

The circumstances that determined his bent towards the investigation of glacial geology cannot perhaps be fully elucidated now in the absence of any statement from his own pen, but it is not difficult to find many reasons that may have influenced him. In considering this subject we may glance briefly at the state of knowledge of this department of geology at the time when he began field work. The years 1861 to 1865 saw a very remarkable development of interest in glacial geology, occasioned by a sudden appreciation of the importance of many facts previously well known but imperfectly understood. Many active geologists in Scotland were coming for the first time to adopt the views which have ultimately obtained acceptance in regard to the Pleistocene history of Scotland, and the change of opinion which was going on was somewhat similar to the still greater change which took place when evolution first began to take the form of a working hypothesis or even an established law of Nature, and to sweep away a great many honoured and treasured theories that had long held sway over the minds of men.

The superficial deposits of sand, clay, and stones that cover the solid rocks in the lower grounds of Scotland, often to a depth of many feet, were considered by most geologists as being of somewhat mysterious origin. It was well known that they contained boulders transported from a distance. Around Edinburgh and Glasgow, for example, large blocks of rock which must have been carried from the Southern Highlands, fifty miles or more, were familiar to those interested in geology. That the surfaces of the rocks on which the drift or boulder-clay rested were striated, grooved, and fluted, was also a well-known fact. Early in the nineteenth century a favourite explanation of these deposits, which had been supported by the celebrated Dean Buckland, was that they were the remains of the Deluge as described in Genesis. This theory, however, was soon discarded though the name " Diluvial," still used by some writers to designate these strata, bears witness to the former acceptance of that hypothesis. For a long time they continued to be considered as flood deposits, laid down by " debacles " of obscure origin. No rational explanation for these powerful "waves of translation" could be formulated, and they failed completely to account for the remarkable scratched surfaces on which the boulder-clay rested. As the study of glaciers advanced, it became clear that moving ice, bearing debris with it, could produce striations exactly like those in question, and the boulder-clay gradually came to be considered a glacial deposit. Very important confirmation of this hypothesis came from the observations of Mr Smith of Jordanhill on the recent shelly clays of the west of Scotland. Many of the mollusca which these clays contained proved to be of species now living in Arctic seas, and the inference was obvious that at no very distant epoch a glacial climate had prevailed in Scotland. About the year 1837 Agassiz had been led by his investigation of the boulder-clay of Switzerland to the conclusion that at one time the glaciers had extended far beyond their present limits, and had covered the plains at the foot of the Alps with a vast confluent sheet of ice. Agassiz, in 1840, visited Scotland with Dean Buckland, and as the result of his observations had not hesitated to declare that Scotland also had been swathed in an ice-sheet. British geologists, however, were slow to accept his conclusions, and the favourite explanation of the " drifts" was that they had been laid down at the bottom of a sea in which icebergs floated, transporting great rock boulders from one place to another.

In 1866 the veteran geologist Charles Maclaren, then at the age of eighty-four, published the second edition of his Geology of Fife and the Lothians, and in his account of the "alluvial phenomena" of the district he shows the transitional state in which opinion then was passing from the iceberg hypothesis to the land-ice hypothesis. "The dressed surfaces as well as the 'Till' or Diluvium [the lower boulder-clay] seem to have been mainly due to a great envelope of ice acting for ages; the newer alluvium, on the other hand [the upper boulder-clay], appears to have been chiefly due to icebergs and ocean currents. In thus attributing so much to the action of ice during a long glacial period, it must ever be borne in mind that oceanic currents preceded this ice action, and that similar currents must have been in existence to transport the icebergs to which we ascribe the erratic blocks and boulders. Alternate submergence and elevation of the north of Europe, combined with ice on land and ice on water (in my opinion), must satisfactorily explain these diluvial phenomena, which, as unsettled problems, are still engaging the attention of younger geologists."

One of the ablest champions of the land-ice hypothesis was Robert Chambers, who was widely known as a historian and a member of the famous Edinburgh publishing firm. As early as 1852 he ranged himself on the side of Agassiz, declaring that floating icebergs and currents of water could not possibly be accepted as a satisfactory explanation of the boulder-clay and striated rock-surfaces. Mr T. F. Jamieson of Ellon was making a very careful study of the drifts of Aberdeenshire and the adjacent counties, and had little hesitation in accepting the theory of an extensive ice-sheet, covering these districts and filling up all the valleys, as the explanation most in accordance with the facts which he had observed. He admitted, however, that subsequently there had been a great submergence during which many of the uppermost drift deposits had been laid down.

Sir Charles Lyell, whose authority on questions of theoretical geology at that time was paramount, was also willing to accept the former existence of glaciers over very extensive regions of the British Isles, and described moraines that occur in the upland valleys of Forfarshire, though he considered the drifts of the lower grounds as mainly at any rate deposited in cold seas in which icebergs floated. Much more important than Lyell, or at least much more likely to exert influence on the mind of James Geikie at an early stage in his career, was Sir Andrew Ramsay, then local Director of the Geological Survey. Ramsay was a man after James Geikie's own heart, and therecan be no doubt that his influence on Geikie was very great. We should not be far wrong, in fact, in regarding Geikie as the direct successor of Ramsay in the line of scientific thought. Through his whole life James Geikie hardly departed from the position taken up by Ramsay on glacial geology, though of course he developed many new and important fields of investigation. There was a remarkable similarity in their outlook; they both relied on very much the same class of evidence, depending specially on field geology as a basis, but prepared to build up far-reaching deductions from the facts they had observed. Most of the theories enunciated by Ramsay were strongly and consistently maintained by James Geikie up to the close of his career. Ramsay also was more than a glacialist. He left a deep mark in the study of physiography, the origin and history of British scenery, and in structural geology; and in these subjects also James Geikie found continual inspiration.

When Geikie joined the Survey, Ramsay was at the zenith of his powers. He had been for twenty years an active field-geologist on the Survey staff; had travelled very extensively over Great Britain on geological work; was a well-known man in London scientific circles; and from his official position had unrivalled opportunities of making himself acquainted with the field evidence bearing on all geological questions then under review. He was endowed with great energy and a warm imagination; a genial and hearty comrade, very fond of a joke; well read in poetical and romantic literature; but withal a hard, untiring worker who never spared himself or any member of his staff where duty was concerned. The two men were in many ways alike, and no doubt they were very soon on terms of close friendship; and to the latest days of his life James Geikie spoke of Ramsay with deep affection and respect.

To the influence of Ramsay we must add that of his brother. Archibald Geikie was already widely known for his geological work, and second only to Ramsay as an authority on theoretical questions affecting British geology. He had been appointed to the staff of the Geological Survey in 1855, six years before James Geikie, and had rapidly risen into prominence. Although at first he had given his adhesion to the iceberg theory, his views had changed under the influence of Ramsay, and in a classic paper which he read to the Geological Society of Glasgow in 1862 he had described the glacial deposits of Scotland in an exhaustive manner. This paper, so full in its details and so lucid and moderate in statement, produced a great impression, at any rate in Scotland, and clearly marked out the way along which future progress was to be made. Though Sir Archibald Geikie subsequently made few contributions to glacial geology, deserting this field for the study of volcanoes, and of other parts of physical and historical geology, he did a very great service to science in so clearly defining his position on a much debated subject by publishing this paper.

As time went on, some of the younger geologists who had joined the Survey after James Geikie became enthusiastic workers at glacial science, and came to earn a reputation only second to Geikie himself in this department of geology. Of these, we may specially mention Dr John Home and Dr Benjamin N. Peach, both of whom- became eminent authorities on the glacial geology of Scotland. In early years they were James Geikie's most intimate friends; their observations were always at his service, and their criticism and advice he greatly valued.


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