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But early in August he was back in London, hard at work in writing and correcting proofs. This business detained him longer than he anticipated, but his labours were cheered by the news of the eruption of Graham's Island. Here was another case in support of the thesis which he was ready to maintain against all comers. But a few months since there had been a depth of eighty fathoms, as was proved by sounding, on the site of this island. Now the cone "is 200 feet above water and is still growing.⁴⁹ Here is a hill 680 feet, with hope of more, and the probability of much having been done before the 'Britannia' sounded." Surely Nature herself was testifying "her approbation of the advocates of modern causes! Was the cross which Constantine saw in the heavens a more clear indication of the approaching conversion of a wavering world?"

But in the beginning of September Lyell broke away from the emissaries of the press and took passage by sea to Edinburgh, there to combine business with a fair amount of both scientific work and social pleasure. This visit afforded him an opportunity of hearing Chalmers preach. In a letter to Miss Horner he gives a brief abstract, and expresses his general opinion of the sermon⁵⁰: —

"It was a very long discourse, but admirable. The subject was 'repentance,' a hackneyed one enough… He explained the effect of habit, and its increasing power over the mind, as a law of our nature, with as much clearness and as philosophically as he could have done had he been explaining the doctrine to a class of university students in a lecture on the philosophy of the human mind. But then the practical application was enforced by a strain of real eloquence, of a very energetic, natural, and striking description… But, unfortunately, every here and there he seemed to feel that he was sinning against some of the Calvinistic doctrines of his school, and all at once there was some dexterous pleading about 'original sin,' which interfered a little with the free current of the discourse… Upon the whole, however, judging from this single specimen, I think I would sooner hear him again than any preacher I ever heard, Reginald Heber not excepted."

At this time Lyell was keeping a journal, which was forwarded to Miss Horner, then in Germany, to serve apparently as a substitute for ordinary letters; home news, disturbances arising from the struggle over the Reform Bill, visits of friends, geological researches, walks on the hills to search for plants or for insects, the habits of the Kinnordy bees, or the accomplishments of two parrots, brought from Africa by his naval brother – all being jotted down just as they occurred.

Among this farrago– though not of nonsense – geological topics, since Miss Horner had similar tastes, occupy a considerable space. She, however, evidently was, comparatively speaking, a beginner, and in one or two characteristic sentences her lover and preceptor passes from information to counsel: "If you are not frightened by De la Beche, I think you are in a fair way to be a geologist; though it is in the field only that a person can really get to like the stiff part of it. Not that there is really anything in it that is not very easy, when put into plainer language than scientific writers choose often unnecessarily to employ." He also records⁵¹ a piece of advice from his old friend, Dr. Fleming, which is enough to make a modern professor of geology sigh for "the good old times." He said to Lyell:

"If you lecture once a year for a short course, I am sure you will derive advantage from it. A short practice of lecturing is a rehearsal of what you may afterwards publish, and teaches you by the contact with pupils how to instruct, and in what you are obscure. A little of this will improve your power, perhaps as an author. Then, as you are pursuing a path of original and purely independent discovery and observation, it increases much your public usefulness in a science so unavoidably controversial to have thrown over you the moral protection of being in a public and responsible situation, connected with a body like King's College. But then you must stipulate that you are to be free to travel, and must only be bound to give one short course annually."

Truly those must have been halcyon days for professors!

The journal also proves, by its brief account of a Scotch festival, which accords with little hints dropped elsewhere in it or in letters, that our forefathers, not wholly excluding men of science, some sixty years ago habitually consumed much more "strong drink" than would be considered correct at the present day: —

"It was just an Angus set-to of the old régime. They arrived at half-past six o'clock and waited dinner one hour. Gentlemen rejoined the ladies at half-past twelve o'clock! They, in the meantime, had had tea, and a regular supper laid out in the drawing-room. After an hour with the ladies they returned to the dining-room to supper at half-past one o'clock, and my father left them at half-past two o'clock! The ladies did not go to this supper."

The journal, in short, like the well-known Scotch dish, affords a great deal of "confused feeding" of a pleasant sort, but no samples of love-making. The nearest approach to it is in the following passage, which is worth quoting, not for that reason, but as incidentally disclosing the strength of the author's character: —

"I shall write a few words before I get into the steamboat just to tranquillise my mind a little, after reading several controversial articles by Elie de Beaumont and others against my system. If I find myself growing too warm or annoyed at such hostile demonstrations I shall always retreat to you. You will be my harbour of peace to retire to, and where I may forget the storm. I know that by persevering steadily I shall some years hence stand very differently from where I now am in science; and my only danger is the being impatient, and tempted to waste my time on petty controversies and quarrels about the priority of the discovery of this or that fact or theory."⁵²

Friends in plenty were awaiting him in London, which was reached about the first of November: the Murchisons and Somervilles, Broderip, Curtis, Basil Hall, and Hooker, with Necker from Switzerland, and many more. He is also cheered by finding that his ideas are steadily gaining ground among geologists, converts becoming more confident, unbelievers more uneasy. He made good progress with his book, and realised, before the end of the year, that his materials could not be compressed into a single volume; so he determined to issue the part already completed as a second volume, and to finish the work in a third.

From time to time the diary contains references to a recent contest for the Presidency of the Royal Society, and to political matters such as the Reform Bill; but, though in favour of the latter, he is not very enthusiastic on the subject, for on one occasion he expresses regret at having been absent, through forgetfulness, from a meeting of the Geographical Society, where he would have "got some sound information instead of hearing politicians discuss the interminable bill."

The lectures at King's College evidently weighed upon his mind as they drew near, and he was not stirred to enthusiasm by the prospect of teaching; for towards the close of the year he more than once debated with his friends the question whether or no he should retain the appointment. Murchison was in favour of resignation; Conybeare took the opposite view. Of his advice Lyell remarks, "The fact is, Conybeare's notion of these things is what the English public have not yet come up to, which, if they had, the geological professorship in London would be a worthy aim for any man's ambition, whereas it is now one that the multitude would rather wonder at one's accepting."⁵³ The British public apparently still lags a long way behind the Conybearian ideal, and retains its contempt for all those who, by presuming to teach, insinuate doubts as to its innate omniscience.

Lyell, however, clearly perceived that it was absolutely necessary that every teacher of professorial rank should be himself a pioneer in his subject – a fact of which government officials, as a rule, seem to be totally ignorant. His comments, a little later in the year, on the arrangements at the University of Bonn are worth recording. "The Professors have to lecture for nine months in the year – too much, I should think, for allowing time for due advancement of the teacher." Lyell's desires in regard to remuneration seem reasonable enough. He is anxious to earn by his scientific work enough to provide for the extra expenses which this work entails, and yet to command sufficient time to advance his knowledge and reputation. The fates proved more propitious to him than they are generally to men of science, for he succeeded in accomplishing both of his desires.

Little of importance happened during the early part of 1832. There was plenty of hard work in collecting facts, in consulting friends about special difficulties, and in working at the manuscript for the third volume of the "Principles," for the second made its appearance almost with the new year. Toil was sweetened by occasional pleasures, such as an evening with the Somervilles, or a dinner party at the Murchisons, a talk with Babbage or Fitton, or a symposium at the Geological Club, at which it is sometimes evident that good care was taken lest science should become too dry. One passage in his diary indicates that sixty years have considerably changed the habits of life in town and in the country, for at the present day most people would express themselves in the opposite sense. "I have enjoyed parties and two plays this month very much, because it was recreation stolen from work; but the difficulty in the country is that, on the contrary, one's hours of work are stolen from dissipation."

The lectures at King's College were begun in May. Lyell evidently was not a nervous man, but he regarded the near approach of this new kind of work with some trepidation, and admits that he slept ill before the first lecture. It was, however, a decided success in every respect, and the audience was a large one, for the Council, after some hesitation, had permitted the attendance of ladies. Each lecture was pronounced by the hearers to be better than the last, and Lyell uses the opportunity, as he says, to fire occasional shots at Buckland, Sedgwick, and others who are still hankering after catastrophic convulsions and all-but universal deluges. As a further encouragement, his publisher, Murray, agrees willingly to a reprint of the first volume of the "Principles," and only hesitates between an edition of 750 or of 1,000 copies. About this time, also, he was asked to undertake the presidency of the Geological Society, but that, notwithstanding Murchison's urgency, he firmly declined for the present; writing of it to Miss Horner, "It is just one of those temptations the resisting of which decides whether a man shall really rise high or not in science. For two more years I am free from les affaires administratives, which, said old Brochart in his late letter to me, have prevented me from studying geology d'une manière suivie, whereby you have already carried it so far."

He was, however, soon to be engrossed in an "affair" of another kind; one which has proved very detrimental to the progress of many men of science, but which, in Lyell's case, had the happiest results, and smoothed rather than it impeded his path to fame; for in the summer – on July 12th – he ceased to be a bachelor. The marriage was celebrated at Bonn, where Miss Horner's family were still resident. A Lutheran clergyman seems to have officiated, and the ceremony was a very quiet one; the distance from home preventing the attendance of English friends or even of relations of the bridegroom.

The newly-married couple departed from Bonn up the Rhine, and travelled by successive stages to Heidelberg, but they were not forgetful of geology, even in the first week of the honeymoon, for they visited as they journeyed more than one interesting section on the western edge of the Odenwald. Then they made excursions to Carlsruhe and Baden-Baden, and ultimately travelled from Freiburg to Schaffhausen through the romantic defiles of the Höllenthal, and across the corner of the Black Forest. A journal was now needless, and probably the newly-married couple were too much engrossed with their own happiness to write many letters, for few details have been preserved about their Swiss tour. It was, however, comparatively a short one, for they remained less than a fortnight in the country. Still Lyell probably found it useful in refreshing recollections and testing his early impressions by greatly increased knowledge and experience. From the valley of the Rhone they crossed the Simplon Pass into Italy and followed the usual road to Milan along the shore of the Lago Maggiore.

How long they remained in Italy, or by what route they returned to England, is not stated; indeed, for nearly six months next to nothing is on record concerning Lyell's movements or work, but in the beginning of 1833 he and his wife were settled in London at No. 16, Hart Street, Bloomsbury, which became their residence for some years. A state of happiness is not always indicated by much correspondence: probably it was so with Lyell; at any rate, a single letter, dated January 5th, gives the only information of his doings between September, 1832, and April, 1833. In this letter, however, he mentions that the Council of King's College had decided that in future ladies should not be admitted to Lyell's lectures, and that, in consequence, he had received a pressing invitation from the managers of the Royal Institution to give, after Easter, a course of six or eight lectures in their theatre, coupled with the offer of a substantial remuneration.

At the end of April, as he tells his old friend Mantell, both these courses had been begun. The one at the Royal Institution was attended by an audience of about 250, that at King's College, after the opening lecture, dropped down to a class of fifteen. The falling-off was entirely due to the above-named resolution. For this the Council had assigned a reason, which, perhaps, was not a prudent course, for bodies of that kind, when they give reasons, often succeed only in "giving themselves away." The presence of ladies was forbidden, "because it diverted the attention of the young students, of whom," Lyell remarks sarcastically, "I had two in number from the college last year and two this." Had the Council stated boldly that the College did not appoint professors to lecture urbi et orbi, their policy, though it would have appeared a little selfish and might have proved shortsighted, would have been defensible, because the institution was founded for the education of a particular class. But the reason assigned was open to Lyell's retort, and gave the impression of unreality. It is not impossible that the decision was the result of secret "wire-pulling," and represented not so much a fear of the disturbing influence of the fair sex as a dread of the popularity of the subject. Geology was still regarded with grave distrust by a very large number of people, and King's College, it must be remembered, was founded in the supposed interests of the Church of England and in the hope of neutralising the effects of the unsectarian institution in Gower Street. Many of its supporters may have been characterised rather by the ardour of their dislikes than by the width of their sympathies, and may have put pressure on the Council, so that this body may have considered it safer to risk driving a popular man from their staff than to alienate an important section of their adherents and to expose the College to the danger of being charged with lending itself to heretical teaching.⁵⁴

The preparation of these lectures must have been attended with some difficulty, for Lyell writes that, "like all the world," he and his household – everyone except his wife – had been down with the influenza, which in that year was even more rampant in London than it has been in any of its recent visits. But, notwithstanding this and any other interruptions, the third and final volume of the "Principles of Geology" made its appearance in the month of May, 1833.

CHAPTER V.
THE HISTORY AND PLACE IN SCIENCE OF THE "PRINCIPLES OF GEOLOGY."

The publication of the last volume of the "Principles of Geology" formed an important epoch in Lyell's life. It brought to a successful close a work on which his energies had been definitely concentrated for nearly five years, and for which he had been preparing himself during a considerably longer time. It placed him, before his fourth decade was completed, at once and beyond all question in the front rank of British geologists; it carried his reputation to every country where that science was cultivated. It proved the writer to be not only a careful observer and a reasoner of exceptional inductive power, but also a man of general culture and a master of his mother tongue. The book, moreover, marked an epoch in geology not less important; it produced an influence on the science greater and more permanent than any work which had been previously written, or has since appeared – greater even than the famous "Origin of Species by Natural Selection," for that dealt only with one portion of geology – viz. with palæontology, while the method of the Principles affected the science in every part. For a brief interval, then, we may desert the biography of the author for that of the book – the parent for his offspring – and call attention to one or two topics which are more immediately connected with the book itself. A brief sketch of its future history may be placed first; for, as its author was constantly labouring to improve and perfect his work, it underwent many changes in form and arrangement during the remainder – some two-and-forty years – of his life, which will be better understood from a connected statement than if they have to be gathered from scattered references in the other chapters of his biography.

The first volume of the "Principles of Geology" appeared, as has been mentioned, in January, 1830; the second in January, 1832; and the third in May, 1833. But a second edition of the first volume was issued in January, 1832, and one of the second volume in the same month of 1833; these were all in 8vo size. A new edition of the whole work was published in May, 1834. This, however, took the form of four volumes 12mo. This edition was called the third, because the first two volumes of the original work had gone through second editions. A fourth edition followed in June, 1835, and a fifth in March, 1837.

Thus far the "Principles" continued without any substantial alteration, but the author made an important change in preparing the next edition. He detached from it the latter part – practically, the matter comprised in the third volume of the original work. This he rewrote and published separately as a single volume in July, 1838, under the title of "Elements of Geology"; a sixth edition of the "Principles," thus curtailed, appeared in three volumes 12mo, in June, 1840. The effect of the change was to restrict the "Principles" mainly to the physical side of geology – to the subjects connected with the morphological changes which the earth and its inhabitants alike undergo. Thus it made the contents of the book accord more strictly with its title, while the "Elements" indicated the working out of the aforesaid principles in the past history of the earth and its inhabitants – that is, the latter book deals with the classification of rocks and fossils, or with petrology and historical geology. The subsequent history of the "Elements" may be left for the present.

In February, 1847, the seventh edition of the "Principles" appeared, in which another change was made. This, however, was in form rather than in substance, for the book was now issued in a single thick 8vo volume. The eighth edition, published in May, 1850; and the ninth, in June, 1853, followed the same pattern. A longer interval elapsed before the appearance of the tenth edition, and this was published in two volumes, the first being issued in November, 1866, and the second in 1868. In this interval – more than thirteen years – the science had made rapid progress, and the process of revision had been in consequence more than usually searching. The author, as he states in the preface, had "found it necessary entirely to rewrite some chapters, and recast others, and to modify or omit some passages given in former editions." Many new instances were given to illustrate the effect which forces still at work had produced upon the earth's crust, and these strengthened the evidence which had been already advanced. Into the accounts of Vesuvius and Etna much important matter was introduced, the result of visits which, as we shall find, Lyell made in 1857 and 1858; the chapters relating to the vicissitudes of climate in past geological ages were entirely rewritten, together with that discussing the connection between climate and the geography of the earth's surface; and a chapter, practically new, was inserted, which considered "how far former vicissitudes in climate may have been influenced by astronomical changes; such as variations in the eccentricity of the earth's orbit, changes in the obliquity of the ecliptic, and different phases of the precession of the equinoxes." But the most important change was made in the later part of the book – the last fifteen chapters.⁵⁵ These either were entirely new, or presented the original material in a new aspect. In the earlier editions of his work, Lyell had expressed himself dissatisfied, as we have already seen, with the idea of the derivation of species from antecedent forms by some process of modification, and had pointed out the weak places in the arguments which were advanced in its favour. But the evidence adduced by Darwin and Wallace in regard to the origin of species by natural selection, strengthened by the support of Hooker on the botanical side, had removed the difficulties which the cruder statements of Lamarck and other predecessors had suggested to his mind, so that Lyell now appears as a convinced evolutionist. The question also of the antiquity of man is much more fully discussed than it had been in the earlier editions.

Considerable changes were introduced into the eleventh edition, which appeared in January, 1872, but these were chiefly additions which were made possible by the rapidly increasing store of knowledge, as, for instance, much important information concerning the deeper parts of the ocean. On this interesting subject great light had been thrown by the cruises of the several exploring vessels, notably those of the Lightning, the Bulldog, and the Porcupine, commissioned by the British Government – cruises in the course of which soundings had been taken and temperatures observed in the North Atlantic down to depths of about 2,500 fathoms; and in the lowest parts of the western basin of the Mediterranean. Samples also of the bottom had been obtained, and, in many cases, even dredgers had been successfully employed at these depths. Thanks to the skill of the mechanician, the way had been opened which led into a new fairyland of science. This was not, like some fabled Paradise, guarded by mountain fastnesses and precipitous ramparts of eternal snow; it was not encircled by storm-swept deserts, or secluded in the furthest recesses of forests, hitherto impenetrable; but it lay deep in the silent abysses of ocean – on those vast plains, which are unruffled by the most furious gale, or by the wildest waves. In these depths, beneath the tremendous pressure of so vast a thickness of water, and far below the limits at which the existence of life had been supposed to be possible, numbers of creatures had been discovered – many of them strange and novel: molluscs, sea-lilies, glassy sponges of unusual beauty – creatures often of ancient aspect, relics of a fauna elsewhere extinct; and the ocean floor, on and above which they moved, was strewn with the white dust of countless coverings of tiny foraminifera, which, even if none were actually living, had fallen like a gentle but incessant rain from the overhanging mass of water.

Similar changes were introduced into the twelfth edition of the "Principles," upon which the author was engaged even up to the last few weeks of his life. The Challenger, it will be remembered, started on her memorable voyage of exploration at the close of the year in which the eleventh edition had appeared; and though she did not actually return till after Lyell's death, notes of some of her most interesting discoveries had been communicated from time to time to the scientific journals of this country. The edition, however, was left incomplete. The first volume had been passed for the press, but the second was still unfinished; so that this twelfth edition was posthumous, the work of revision having been finished by the author's nephew and heir, Mr. Leonard Lyell.

By such conscientious and unremitting labour, the scientific value of the "Principles" was immensely increased; it kept always in step with the advance of the science, but at the same time it lost, as was inevitable, a little of that literary charm and that sense of freshness which was at first so marked a characteristic. Books, like children, are apt to lose some of their beauty as they increase in size and strength. One must compare an early and a late edition, such as the first or third and the tenth or eleventh, in order to realise how great were the changes in this passage from childhood to adolescence. New material was incorporated into every part; it makes its appearance sometimes on every page; changes are made in the order of the subjects; many chapters are entirely rewritten; nevertheless, a considerable portion corresponds almost word for word in the two editions. Lyell was no hurried writer, or "scamper" of work; he paid great attention to composition, so that when the facts which he desired to cite had undergone no change, he very seldom found any to make in his language. Nevertheless, here and there, some small modification, a slight verbal difference, a trifling alteration in the order of a sentence, the insertion of a short clause to secure greater perspicuity, shows to how careful and close a revision the whole had been subjected. In the substance of the work, besides the excision of nearly one-third of the material and the complete reconstruction of the part relating to the antiquity of man and the origin of species, already mentioned, the following are the most important changes. The chapters which discuss the evidence in favour of past mutations of climate and the causes to which these are due, are rewritten and greatly enlarged. In the earlier editions, the effects of geographical changes were regarded as sufficient to account for all the climatal variations that geology requires; in the later editions, the possible co-operation of astronomical changes is admitted. Great additions also are made to the parts referring to the condition of the bed of the ocean, and much new and important information is incorporated into the sections dealing with volcanoes and earthquakes; including many valuable observations which had been made during visits to Vesuvius and to Etna in the autumns of 1857 and 1858. The section on the action of ice is so altered and enlarged as to be practically new; for when the first edition of the "Principles" was published comparatively little was known of the effects of land-ice, and the art of following the trail of vanished glaciers had yet to be learnt. But, with this exception, the part of the book dealing with the action of the forces of Nature – heat and cold, rain, rivers, and sea – remains comparatively unaltered, as do the first five chapters, which give a sketch of the early history of the science of geology.

Without some knowledge of this history it is hardly possible to appreciate the true greatness of the "Principles," and its unique value as an influence on scientific thought at the time it appeared. This, however, to some extent may be inferred from those chapters which we have mentioned; but the perspective of half a century enables us to understand it better at the present time; for the author, of course, had to deal with contemporary work and opinion only in a very indirect way. We may dismiss briefly the crude speculations of the earliest observers – those anterior to the Christian era – of which the author gives a summary in the second chapter of the "Principles"; for at that early date few persons had made any effort to arrange the facts of Nature in a connected system. These were too scanty and too disconnected for any such effort to be successful. The general result cannot be better summed up than in Lyell's own words: —

"Although no particular investigations had been made for the express purpose of interpreting the monuments of ancient changes, they were too obvious to be entirely disregarded; and the observation of the present course of Nature presented too many proofs of alterations continually in progress on the earth to allow philosophers to believe that Nature was in a state of rest, or that the surface had remained and would continue to remain, unaltered. But they had never compared attentively the results of the destroying and the reproductive operations of modern times with those of remote eras; nor had they ever entertained so much as a conjecture concerning the comparative antiquity of the human race, or of living species of animals and plants, with those belonging to former conditions of the organic world. They had studied the movements and positions of the heavenly bodies with laborious industry, and made some progress in investigating the animal, vegetable, and mineral kingdoms; but the ancient history of the globe was to them a sealed book, and though written in characters of the most striking and imposing kind, they were unconscious even of its existence."⁵⁶

The above remarks hold good for the centuries immediately succeeding the Christian era; and the influence of the new faith, when it ceased to be persecuted and became a power in the state, was adverse on the whole to progress in physical or natural science. With the decline of the Roman empire a great darkness fell upon the civilised world; art, science, literature withered before the hot breath of war and rapine, as the northern barbarians swept down upon their enfeebled master on their errand of destruction. It was well nigh eight centuries from the Christian era before the spirit of scientific enquiry and the love of literature began to awaken from their long torpor; and it was then among people of an Eastern race and an alien creed. The caliphs of Bagdad encouraged learning, and the students of the East became familiar by means of translations with the thoughts and questionings of ancient Greece and Rome. The efforts of their earliest investigators have not been preserved, but in treatises of the tenth century – written by one Avicenna, a court physician, the "Formation and Classification of Minerals" is discussed, as well as the "Cause of Mountains." In the latter attention is called to the effect of earthquakes, and to the excavatory action of streams. In the same century also, "Omar the Learned" wrote a book on "the retreat of the sea," in which he proved by reference to ancient charts and by other less direct arguments that changes of importance had occurred in the form of the coast of Asia. But even among the followers of Mohammed theology declared itself hostile to science; the Moslem doctors of divinity deemed the pages of the Koran, not the book of Nature, man's proper sphere of research, and considered these difficulties ought to be settled by a quotation from the one rather than by facts from the other. So progress in science was impeded, and recantations at the bidding of ecclesiastics are not restricted to the annals of Christian races. But men seem to have gone on speculating, and Mohammed Kazwini, in a striking allegory which is quoted by Lyell, tells his readers how (to use the words of Tennyson)⁵⁷: —