1872 Ramsay, Director General - Geological Survey of Great Britain (by E.B. Bailey)

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From: Bailey, Sir Edward. Geological Survey of Great Britain. London: Thomas Murby, 1952.
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Figure 10 First edition one-inch map publication in decades 1870-1879 (7), 80-89 (8), 90-99 (9). See Figs, 8, 28 pp, 62, 159.)
Figure 11 Weathering of Tunbridge Wells sandstone. (Quoted from Topley, Weald Mem., 1875, p. 247.)
Figure 12 Depositional area of Woolley Edge Rock. Newton Lane Ends to Hemmingfield is 14 miles. (Compare Figure 39, p. 244.) (Quoted from Green, Yorkshire Coalfield Mem., 1878, P. 433.)
Figure 13 Moel Tryfan. 1, Cambrian slate; 2, sand and gravel, with sea shells; 3, Boulder beds. Ramsay's comment: ' He would be a bold man who could see the ground and still maintain that these well-bedded strata have all been shoved up 1,000 ft. out the sea.' (Quoted from Ramsay, Mem., vol. iii, 2nd ed., 1881, p. 277.)
Figure 14 Slieve Gullion Ring-Dyke Complex, 55 m. N. of Dublin, as mapped on one-inch sheets 59, 60, 70, 71 (1874), slightly simplified for reduction. The complex was thought to be Late Paleozoic. It is now known to be Tertiary. Country-Rock (Silurian Greywacke and Newry Granite), left blank; Bm, Micaceous Dolerite; E, Elvanite (Quartz-Porphyry); F, Felstone; Fs, Agglomerate; Broken Lines, Faults.

1872 Ramsay, Director General

IN 1872 Andrew Crombie Ramsay, 59 years old, succeeded Murchison as Director General of the Geological Survey of the British Isles, together with the Museum of Practical Geology and the Office of Mining Records. The governance, however, of the Royal School of Mines passed to a Council of Professors, with Warington Smyth as Chairman.

Thus dissolution started. Chemistry, Physics and Natural History left at once to form the nucleus of New Science Schools, built at South Kensington on ground acquired by the Commissioners of the 1851 Exhibition. In other respects the change was gradual. Huxley divided his allegiance, continuing to function as Naturalist to the Survey at Jermyn Street until 1881. Ramsay, as Professor of Geology, went on lecturing in the old quarters till 1876—when his successor, Judd, who had retired from the Survey in 1871, naturally started in the new buildings. Percy remained at Jermyn Street till his resignation in 1880 ; and Warington Smyth till his death in 1890. The separation might well have broken De la Beche's heart, if he had lived to see it ; but viewed dispassionately it affords striking testimony to the greatness of the founder's success. It was growth and vigour that led to this departure from the parental home. Today the Geological Survey is happy to•recognise in the Imperial College of Science a sturdy, independent offspring.

Bristow succeeded Ramsay as Director for England and Wales. Howell succeeded Bristow as District Geologist. Archibald Geikie and Hull remained Directors for Scotland and Ireland respectively. The field staff averaged 61 during Ramsay's ten years, maintaining for the time being the high numerical level reached in Murchison's last 4 years. On the other hand, Headquarter Staff, owing to the transfer of the Royal School of Mines, averaged 12 instead of 16.

The most interesting enlistments all fell to the English Staff: Jukes-Browne, 1874, later to specialise in successive British geographies; Clement Reid, 1874, to achieve fame in the Pliocene and Pleistocene ; A. Strahan, 1875, a future Director ; C. T. Clough, 1875, and G. 'Barrow, 1876, eventual leaders in Scottish Highland research.

Maps

Ramsay's period saw an approximation to modern standards of field work. Six-inch mapping was the rule, except where, in some south-eastern counties of England, the one-inch map was alone available. Much of the English and Scottish work lay in coalfields and metalliferous districts. Naturally, collection of underground, as well as surface, information made progress relatively slow, now that there was welcome map-space to record considerable detail. In addition drift boundaries had to be traced. So it came about that the hectic rush of former periods was temporarily abandoned.

Publication rate of one-inch maps in England dropped during the 70's to less than half of what it had been during the 60's (Fig. 8). On the other hand, that of six-inch maps rose to nearly three times its previous value. In Scotland, where, it will be remembered, a separate staff had been organised in 1876, the rate of publication of both one-inch and six-inch maps was approximately doubled. In Ireland one-inch publication continued much as in the 60's; while six-inch publication remained a very minor proposition.

Without doubt much of the six-inch publication in the North of England was justified ; but some was excessive, where it covered districts devoid of mining possibilities. It is the easiest type of publication to extract from many a fieldsman, who naturally welcomes quick, large-scale expression of his research ; but such a one is only too apt to turn to another area without troubling overmuch to complete the corresponding one-inch map and its accompanying memoir. Murchison's plan for routine provision of one-inch sheet-explanations has, as we have already noted, only been successfully implemented in Ireland, where Jukes and Hull deserve our special gratitude.

The Annual Report for 1881 contains a statement that: ' In accordance with directions issued by the Department last year the publication of the six-inch maps has been to a large extent suspended …in order that the publication of the one-inch maps may be more rapidly pushed forward.' There can be little doubt that these directions resulted from discussions in which the Department sounded Archibald Geikie regarding the steps he would be prepared to take, after Ramsay's departure, to bring the seemingly interminable geological survey of our islands to a close. In keeping with this we find Geikie two years later, in his Annual Report for 1883, referring to an estimate he had furnished to Ramsay that, with doubled staff working in Scotland, the survey of that country could be completed in eleven years. We also note in the 1881 Report a further statement that Ramsay had sanctioned Geikie's proposition that in future Highland field-work be undertaken on the one-inch, rather than the six-inch scale. Some of the surveyors groaned, and handed in inferior results. Others bought their own supply of six-inch maps, and produced one-inch reductions for inspection. The system was dropped in 1885, when, as we shall presently see, a great shock was experienced in the North-West Highlands.

To return to 1881: The cessation of six-inch publication allowed of a very welcome release during the year of a great accumulation of English one-inch maps, exactly as many (reckoning in quarter-sheets, now the standard unit of publication) as had appeared during the whole of Ramsay's previous nine years of office. It is interesting to compare Ramsay's ten-year total with those of corresponding periods immediately before and after:

Murchison's last ten years, 1862-1871 56
Ramsay's ten years, 1872-1881 34
Geikie's first ten years 1882-1891 67

This is the last comparison of the kind that is feasible. We shall see in the sequel that field work on the primary survey of England, directed to the publication of one-inch sheets carrying Tertiary and Pre-Tertiary outcrops, was finished in the year 1883. Thereafter the field staff retained in England was engaged on drift mapping and revision.

Memoirs and underground water

We have said enough of the absence of descriptions of all too many areas published under Ramsay. If, for a change, we look at the memoirs actually produced, we are considerably cheered by a very fine assemblage indeed. Here we can note only a few outstanding examples.

1872. The fourth and last volume of the serial memoirs instituted by De la Beche deals with the Chalk and Tertiaries of the London Basin. The main author, W. Whitaker, fittingly acknowledges indebtedness to Joseph Prestwich—` for it would be presumptuous indeed for anyone to write on the Eocene Beds of the London district without studying his many papers.' A highly characteristic feature is the devotion of i50 pages to records of wells and bores. Whitaker had already in 1866 prevailed upon the Medical Officer of the Privy Council to allow him to publish an Appendix of this character. Records of underground exploration are of extreme value ; but they are unpalatable to a general geological reader, so that it is difficult for an enthusiastic collector to find a publisher. It is said that Whitaker in after years, a venerable figure, bald on top, but with long white side locks and beard to match, beloved of all, willingly accepted the presidency of any local society which was prepared to reproduce a presidential address consisting largely of the details of well sections. With growing experience, as we shall see, the Geological Survey has got over the difficulty by adopting a policy of segregation. The Survey's usefulness in regard to all aspects of underground water has steadily grown, but the lion's share of the credit still belongs to Whitaker. His services continued officially till his retirement in 1896, and in actual fact till his death in 1925.

In this connexion it is proper to recall the activities of a British Association Committee appointed at the Belfast meeting of 1874 with the formal blessing of Ramsay and Bristow. Its Chairman and Secretary throughout were Survey men, Hull and C. E. de Rance, with Whitaker always on its list of members. Its original title was a ' Committee for investigating the circulation of the Underground Waters in the New Red Sandstone and Permian Formations of England, and the quantity and character of the water supplied to various towns and districts from these formations ' ; but by 1882 its scope had been extended to cover water from all the permeable formations of the country. Its annual reports from 1875 to 1895 helped to emphasise the importance of England's underground water, especially in times of drought ; and two bibliographies of the subject, presented by Whitaker in 1887 and 1895, include 695 items and will always remain valuable works of reference.

Having wandered so far from the London memoir of 1872, provoked by its high water content, we may perhaps transgress further still to note an unusual water inquiry which in 1876 took Ramsay and James Geikie to Gibraltar. A valuable official Report resulted, illustrated by a map and sections on the scale of 25 inches to the mile. This may seem excessive at a time when much of England was being geologically surveyed on the one-inch scale ; but foot for foot Gibraltar is more important to England than most of the home countryside. As might be expected, Ramsay and Geikie during their visit found a great deal of scientific interest outside the water problem. This they communicated to the Geological Society.

In 1873 a large model showing the geology of the London basin was placed on exhibition in the Museum. It may be regarded as an illustration of the 1872 memoir.

1875. The Geology of the Weald is another famous memoir. Ramsay, in a foreword, points out that nine officers had been engaged in the mapping, during a period spread over 20 years; and of these, six had left and one had died. Even so, the author, W. Topley, had produced an ' eminently satisfactory' account. The succession, structure and topographic expression of the district are so marked that it is not surprising that Topley and Jordan had already in 1873 prepared a model to accompany that of London mentioned above. The Weald memoir contains all that it should, including adequate treatment of scenery, economics, water supply and health. Along with many other memoirs of the English branch it owes much of its bibliographical completeness to Whitaker's collecting instinct.

1875. The Geology of Rutland was written by J. W. Judd, gratuitously, to cover his researches while on the Geological Survey, 1867-1871. Judd had been mapping in Lincolnshire independently for 6 or 7 years, when he accepted an invitation from Ramsay to undertake the official survey of Rutland on the zonal lines elaborated by Oppel, Quenstedt, Fraas, Marcou and others on the Continent. The local character of many of the Lower Oolite formations of the Midlands involved the necessity of a new stratigraphical classification. This is accompanied in the memoir by a clear statement of the ideas inherent in zonal research in a district complicated by contemporaneous differences of lithological and faunal facies. Little wonder that Ramsay expressed deep regret that he had not been able to retain the services of this gifted geologist.

1878. The Geology of the Yorkshire Coalfield by A. H. Green and others is in the main an orderly account of the stratigraphy of the Millstone Grit and Coal Measures of Yorkshire, followed by a structural description under 38 district headings, the whole copiously illustrated. It is a great achievement, 823 pages, the largest Survey memoir, I hope, for all time. A less grandiose style is more suitable, especially for coalfield publication, where mining operations are constantly affording new information that cries out for production of new editions. Moreover, the date this memoir carries, 1878, is four years later than that of its main author's resignation to become Professor at Leeds, showing how nearly it might have failed to materialise. Ramsay, in his preface, points to the advantage the Yorkshire Coalfield has gained through six-inch mapping ; and hopes this advantage will soon be shared by coalfields to the south. His wish has taken some 70 years to fulfil.

1881. The second edition of vol. iii. of De la Beche's memoirs, which deals with North Wales, appeared in Ramsay's last year of office. The field section, written by Ramsay himself, shows in its Column of Succession a strong break between Arenig slates, above, and Tremadoc slates, below ; but the Lower Silurian bracket is carried down to the base of Salter and Hicks' Menevian beds, below which comes the Survey's Cambrian, of Murchisonian scope. This does not, however, allow its author to continue his claim that the Cambrian strata, ' excepting annelid burrows, and a doubtful trilobite, have nowhere yielded in England and Wales well authenticated organic remains '—for owing to Hicks' discoveries Ramsay now knows of many pre-Menevian trilobites. The break at the base of the Arenig, Ramsay points out, intensifies towards Anglesey, where ' the Arenig and Llandeilo and Bala series lie directly and unconformably on Cambrian strata,' without intervention of Tremadoc and Menevian. It is a matter of interest, rather than criticism, that Ramsay here speaks of Cambrian in Anglesey, whereas Hicks and Callaway have already used the word Precambrian for the same rocks—the difference seems a trifle meaningless as no one yet had defined the basal zone of the Cambrian.

Ramsay extended greatly his reference to glacial phenomena in this second edition, and introduced new physiographical chapters on the history of the Menai Straits, the Clwd and the Dee. This was in keeping with his heightened interest in river development, as evidenced by his researches on the Moselle, the Rhine and the Po.

Detailed discussion of stratigraphical classification is reserved for the long palaeontological Appendix, which has been greatly extended and brought up to date by Robert Etheridge since Salter's death in 1869. It is full of interesting historical items, and contains among other things many appreciative references to Charles Lapworth's recent work in Scotland; though Etheridge does not think this has much bearing upon North Wales' problems.

Charles Lapworth

In retrospect the years of Ramsay's Director-Generalship are chiefly memorable in our Science as those in which Lapworth, whom we have just mentioned, grew up to be, perhaps, the greatest geologist who has ever lived. All the same, Lapworth's contributions to knowledge, though accepted by Etheridge in 1881, did not produce much immediate effect upon the Geological Survey—as is evidenced, for instance, by the fact that Archibald Geikie in his Memoir on Ramsay, published in 1895, did not find occasion to mention them at all. The feature which gives Lapworth a unique position among geologists is his combination in one person of qualities which are more often distributed among a number of individuals. He had physical and mental capacity for first class field work, with an eye for significant minor features of lithology, a delight in large-scale mapping and a penetrating grasp of structure, even where badly exposed. He had the instinct of a connoisseur, who loved to find and extract his own fossils, and who appreciated them as works of natural art. He could reconstruct the living creatures which fossils represent, studying them as a zoologist, distinguishing them as a systematist, and dating them according to the principles of William Smith, applied with the utmost refinement. Then, too, he was a great reader in his own and foreign tongues, able to extract gold from among dross of a sadly muddled literature ; and a wonderful correspondent, establishing an invigorating interchange of knowledge among contemporary workers engaged on cognate problems. Finally, he was a master of a lucid, logical style and fully realised that research is not completed till it is published for the benefit of others.

Among Survey men, the nearest comparison can be drawn with Peach ; but Peach in matters geological could scarcely read or write ; and in all directions found correspondence an anathema. Apart from his use of the picture books of palaeontology, Peach depended for his knowledge of the work of other men upon his supreme power of conversation ; and if he had not had companions like Archibald Geikie and John Horne to record his ideas he would today be little more than a tradition.

Lapworth was born in 1842. In 1864, after passing out of a training college in the South of England, he accepted a teaching post in Galashiels School, drawn thither by his interest in Sir Walter Scott's writings. He soon found friends among the intelligentsia of the town, such as James Wilson of the Border Record, and had his attention turned to geology. His progress was rapid, for in 1870 he read a paper to the Edinburgh Geological Society dividing by their graptolitic contents the rocks of his district into two great groups, the Galas, younger, and the Moffats, older. In this he did little more than develop in his own locality, and on evidence of his own finding, ideas of his friend-by-correspondence, Professor H. A. Nicholson: but soon he outstripped all competitors, except perhaps G. Linnarsson in Sweden. By 1872 he had divided the Moffat Shales into three main divisions with several subsidiary zones ; by 1878 he had published a great memoir in the Quarterly Journal of the Geological Society dealing comprehensively with this subject ; and by 1882, the year after Ramsay's retirement, in another monumental paper, again in the Quarterly Journal, he had extended his conquest to the widely different facies of the Girvan district.

All this as here narrated may seem good work, but perhaps expectable. To realise its true value one must take count of the difficulties it surmounted, local and external. Among the local difficulties we find the following:—(1) Lithological distinctions, such as may in one part of the Southern Uplands allow of separation of formations, break down, as Lapworth discovered in the course of his researches, in a cross-strike direction, owing to amazing changes in the character and thickness of individual groups. (2) Most of the rock exposures are almost unfossiliferous. (3) Where fossil bands do occur, they often constitute parts of a series, so attenuated that their faunas, mixed on a scree slope or in the collector's bag, are apt to give a false impression of actual admixture in Nature. (4) The district has been subjected to close packing with development of steep isoclinal folds and accompanying faults. (5) Away from stream gorges, the hills are rounded and cloaked with grass or heather—there are no continuous exposures of key horizons, such as so often tie together outcrops in other complicated districts.

To these local difficulties was superadded an external difficulty of imposing magnitude: by far the greater number of the fossils of the region were graptolites, and graptolites had already been condemned by Joachim Barrande as transgressors against William Smith's law of faunal succession. Barrande was a confirmed disciple of Smith in regard to shelly fossils, such as brachiopods and trilobites—so much so that his protests against apparent anomalies reported from Quebec led Logan in 1861 to introduce large-scale over-thrusting into Canadian interpretations ; but graptolite faunas, Barrande imagined from his own misreading of Bohemian tectonics, were capable of establishing a succession of temporary colonies in advance of their main entry into an area. Barrande's theory of colonies seems to have been adopted, to some extent at least, by all pre-Lapworthian British workers. Indeed, many of Lapworth's contemporaries, when speaking in public, deprecated the attention that he was paying to lowly organisms ' and, in private, expressed more freely their contempt for his damned graptolites.' Nowadays, of course, Lapworth's graptolite zones in the Lower Palaeozoic are as universally admired as the ammonite zones in the Jurassic worked out by Oppel and others some twenty years earlier. Graptolite zones, as soon as unravelled, have always been found to harmonise with trilobite zones, such as Salter and Hicks established in South Wales. Examples of this began to be realised in the latter district as early as 1872, by Hopkinson.

It must be admitted that the Geological Survey Staff in Southern Scotland under Archibald Geikie, working and publishing concurrently with Lapworth, were as slow as anybody else to accept the revolution of values introduced by the latter. Horne, a careful and diligent reader, first saw the light. Often he asked Peach whether, supposing Lap-worth's fossil facts were dependable, one had any option but to accept his conclusions ; and in after years he constantly congratulated himself on having been able to defer the publication of the Moffat and Loch Doon one-inch sheets for -Which he was largely responsible until, as we shall presently see, Lapworth's results came to be officially recognised.

Meanwhile, let us remember that Barrande's martialling of evidence in support of his colonies was not altogether labour lost. I feel certain that it helped Lapworth greatly both in his realisation and in his demonstration of the broad significance of the secrets he wrested from the uninviting exposures of Southern Scotland. To avoid misconception, let us add that no one questions the importance of migration in interpreting certain aspects of fossil sequence. For instance, shelly faunas, interbedded between graptolitic faunas, owe their position to migration, not, of course, to evolution in situ. Equally certainly Birkhill graptolites replace Hartfell graptolites towards the top of the Moffat Shales, by migration—unless one is prepared to invoke the aid of special creation. Where Barrande has been corrected is in regard to particular misapplications which he made of the migration concept.

Microscopic petrology

Lapworth, in his successful attack upon the graptolite problem, inherited a wealth of experience not available to William Smith, experience so full as to include detailed palaeontological descriptions by men such as Barrande of Bohemia and Hall of New York ; but his only instrumental advantage over the Father of English Geology lay in his possession of large-scale maps. Now let us turn to a totally different field of research, modern petrology, the very inception of which depended upon the introduction of microscopic examination of thin slices of rocks, whereby much that was formerly invisible came clearly into view. It was in Ramsay's Director-Generalship that microscopic petrology began to figure somewhat prominently in Survey work, though Ramsay himself was quite unimpressed by its possibilities.

Hutton, it may be noted, had employed a ' microscope ' (the word may perhaps mean no more than a lens) to examine surfaces of fine-grained rocks for evidence of origin ; and others, from about the same early date, had similarly studied rock powders and residues. The real foundations, however, of microscopic petrology were not laid till the 1820's, when William Nicol, soon to become inventor of the nicol prism, began to grind thin slices for mineralogical and palobotanical research. Henry Clifton Sorby, apprised of Nicol's technique, turned it to more direct geological advantage. In 1850 (published 1851) he communicated to the Geological Society a paper on the Calcareous Grit of Yorkshire, in which he gives an account of the microscopic appearance of thin slices as well as of acid-resistant concentrates. Sorby continued to publish at intervals, always with some definite point of view. We may note, for instance, in 1858 a particularly thoughtful micropetrological discussion, supported by experimental detail, in which he extracted much information from the cavity-fillings of rock-forming minerals. Another skilful pioneer was the far-travelled chemist, mineralogist and geologist, David Forbes, whose best known writing on the subject, The Microscope in Geology, appeared in 1867 as a guide to beginners. In this excellent work, which is beautifully illustrated, little mention is made of polarised light. On the other hand, S. Allport, a business man of Birmingham, produced a stream of important papers, starting in 1869, all of which benefited conspicuously from the use of crossed nicols. A characteristic feature of Allport's researches is his conviction of the essential identity of ancient igneous rocks in Britain with much more modern lavas of the Rhine and Central France, ' another proof,' he said in 1870, ' of the doctrine long taught by Lyell—the uniformity and continuity of the laws of Nature.'

By this time Germany had become the main focus of petrological research. Zirkel, whom Sorby had initiated into his methods in 1862, Vogelsang and Rosenbusch advanced our knowledge by leaps and bounds. At home a few members of the Survey took a hand in the general progress. Geikie recalls how Zirkel, on first meeting him in 1868 at Largs, where he was investigating the Carboniferous lavas of the Clyde, was surprised to find a microscope and thin slices among his household goods. Others of like mind were Clifton Ward and Rutley in England, and Hull in Ireland. Ramsay's lack of enthusiasm for minutiae did not prevent Ward's memoir on The Northern Part of the Lake District, 1876, and Rutley's on The Eruptive Rocks of Brent Tor, 1878, from carrying coloured illustrations of microslices nor did it hinder Geikie from establishing primitive chemical and slicing departments at his Edinburgh headquarters—a most valuable innovation. Rutley also started a petrographical laboratory in London.

Hull, in the Geological Magazine for 1873, pointed to appreciable differences between the Irish Carboniferous basalts (Limerick) and their Tertiary compeers (Antrim).

This observation holds good for the British area as a whole ; but it allows us still to subscribe to Allport's broad generalisation regarding magmatic uniformity and continuity for the world, a much larger whole. Further experience has shown that, if no attention be paid to locality, the total possibilities of magma seem to be essentially the same today as in all preceding geological periods.

Volcanoes and glaciers

Apart from microscopic research one of the most interesting steps taken about this time in the study of vulcanology was the publication, 1875-6, of four Irish one-inch sheets showing a Tertiary ring-dyke complex at Slieve Gullion. The authors responsible, F. W. Egan, J. Nolan and W. A. Traill, did their work well ; but do not seem to have realised that they were introducing a new idea into igneous tectonics. It was 30 years before much more was to be heard on the subject.

Here a few words may be added in regard to Archibald Geikie's outstanding contributions to the history of vulcanicity in the British Isles. His interest in the subject antedated his entry into the Survey in 1855. His publications are many, and among them his share in the official memoirs on Mid and East Lothian, 1861 and 1866, show great skill in dealing with field relations of lavas, ashes and intrusions. In 1866 he announced a new point in Scottish geology: the discovery of Permian eruptions and associated necks in Ayrshire. In 1867, in a Sectional Presidential Address to the British Association at Dundee, he was able to offer a complete review of British vulcanicity. All this was before Ramsay became Director General, and even before Zirkel in 1870 and 1871 began publishing microscopic descriptions of Scottish rocks.

In 1874, Judd opened a new chapter. He had come to Scotland to study the Mesozoic sediments of the country, and now he startled the Geological Society with a long field and microscope account of the Tertiary volcanic rocks, which in the West have sheltered so many occurrences of their frail predecessors from destruction by erosion. As in Geikie's own early work there was much in Judd's account that was crude and mistaken, largely because of the poor maps available at the time ; but subsequent criticism has left a great deal more of permanent value than at one time seemed likely. We shall return later to the Judd-Geikie controversy, which had its origins in this 1874 paper. Meanwhile, we may note that Judd administered a substantial additional pinprick nearer home, when in 1875, he corrected an interpretation of the Carboniferous volcano of Arthur's Seat, Edinburgh, which Geikie had adopted in his boyhood from Charles Maclaren. Geikie's next great volcanic paper was published by the Royal Society of Edinburgh in 1880, and deals with The Carboniferous Volcanic Rocks of the Basin of the Firth of Forth—their Structure in the Field and under the Microscope

Glaciation figures prominently as a subject among outside papers by the staff in England, Scotland and Ireland. For instance, in 1870 Croll had published on The Boulder-clay of Caithness a Product of Land-ice.' He argued from available information, gathered by others, that Caithness, the Orkneys and Shetlands had been glaciated by a confluent Scotto-Scandinavian ice-sheet. This grand conception Peach and Horne confirmed in 1879 and 1880 as a result of holiday excursions. Their holiday work arose largely from an idea, which Archibald Geikie held in common with a number of others similarly situated, that the head of a research institute should act as mouthpiece for any extra-official announcement of results obtained by its members in the course of their duties. It is refreshing to think of the curious circumstances from which good has sometimes resulted.

Perhaps the most important extra-official publication of the period by a Survey man was James Geikie's book, The Great Ice Age, which first appeared in 1874. It produced a profound impression on glacial investigation, both at home and abroad.

Ramsay, Huxley and Croll retire

In 1881 Ramsay retired at the age of 65. Worn out by his long and fruitful service, he had not the strength to contribute further serious work before his death in 1891. He was knighted in 1881, and had received the Royal Medal of the Royal Society in 1879 and the Wollaston of the Geological in 1871. The Royal Medal has been awarded to nine (including Ramsay) whose names figure on the Geological Survey roll, four of them geologists.

The same year, 1881, saw the virtual severance of Huxley's long and honourable connection with the Geological Survey. He left to become Dean of the Royal College of Science. It was also marked by the resignation of James Croll. Poor Croll's infirmities had increased, and for a time he lost the power of intelligible speech. The Civil Service authorities allotted him the minimum pension corresponding with his years of service; so that he found his income reduced from £350 to £75 16s. 8d. Encouraged by friends, he made three applications for a further pension on the Civil List, two during Gladstone's premiership, and one during Salisbury's. His sad fate aroused almost as much sympathy as if he had been convicted of a romantic murder. One of his appeals, for instance, carried the signatures of 4 Dukes, 1 Marquis, 14 M.P.'s, The President, 3 Vice-Presidents and 62 other Fellows of the Royal Society, the Poet Laureate and 39 others holding distinguished places in academic and ecclesiastic life. The net result was disappointing, merely £Ioo from the Queen's Bounty. Croll's friends, however, made life livable, and with ameliorated health he continued working to the end, giving all the time he could spare to his dearest love, Philosophy. In 1889 and 1890, unable to write, he dictated The Philosophical Basis of Evolution, which he had the great satisfaction of seeing in print in the autumn of the latter year, before he himself closed his eves for the last time on this world of struggle.