Louis Agassiz: His Life and Correspondence Part 14

. . .Lyell has adopted your theory in toto!!! On my showing him a beautiful cl.u.s.ter of moraines, within two miles of his father's house, he instantly accepted it, as solving a host of difficulties that have all his life embarra.s.sed him. And not these only, but similar moraines and detritus of moraines, that cover half of the adjoining counties are explicable on your theory, and he has consented to my proposal that he should immediately lay them all down on a map of the county and describe them in a paper to be read the day after yours at the Geological Society. I propose to give in my adhesion by reading, the same day with yours, as a sequel to your paper, a list of localities where I have observed similar glacial detritus in Scotland, since I left you, and in various parts of England.

There are great reefs of gravel in the limestone valleys of the central bog district of Ireland. They have a distinct name, which I forget. No doubt they are moraines; if you have not, ere you get this, seen one of them, pray do so.* (* Aga.s.siz was then staying at Florence Court, the seat of the Earl of Enniskillen, in County Fermanagh, Ireland. While there he had an opportunity of studying most interesting glacial phenomena. ) But it will not be worth while to go out of your way to see more than one; all the rest must follow as a corollary. I trust you will not fail to be at Edinboro'

on the 20th, and at Sir W. Trevelyan's on the 24th. . .

A letter of later date in the same month shows that Aga.s.siz felt his views to be slowly gaining ground among his English friends.

LOUIS AGa.s.sIZ TO SIR PHILIP EGERTON.

LONDON, November 24, 1840.

. . .Our meeting on Wednesday pa.s.sed off very well; none of my facts were disturbed, though Whewell and Murchison attempted an opposition; but as their objections were far-fetched, they did not produce much effect. I was, however, delighted to have some appearance of serious opposition, because it gave me a chance to insist upon the exactness of my observations, and upon the want of solidity in the objections brought against them. Dr. Buckland was truly eloquent. He has now full possession of this subject; is, indeed, completely master of it.

I am happy to tell you that everything is definitely arranged with Lord Francis,* (* Apropos of the sale of his original drawings of fossil fishes to Lord Francis Egerton.) and that I now feel within myself a courage which doubles my strength. I have just written to thank him. To-morrow I shall devote to the fossils sent me by Lord Enniskillen, a list of which I will forward to you. . .

We append here, a little out of the regular course, a letter from Humboldt, which shows that he too was beginning to look more leniently upon Aga.s.siz's glacial conclusions.

HUMBOLDT TO LOUIS AGa.s.sIZ.

BERLIN, August 15, 1840.

I am the most guilty of mortals, my dear friend. There are not three persons in the world whose remembrance and affection I value more than yours, or for whom I have a warmer love and admiration, and yet I allow half the year to pa.s.s without giving you a sign of life, without any expression of my warm grat.i.tude for the magnificent gifts I owe to you.* (* Probably the plates of the "Fresh-Water Fishes" and other ill.u.s.trated publications.)

I am a little like my republican friend who no longer answers any letters because he does not know where to begin. I receive on an average fifteen hundred letters a year. I never dictate. I hold that resort in horror. How dictate a letter to a scholar for whom one has a real regard? I allow myself to be drawn into answering the persons I know least, whose wrath is the most menacing. My nearer friends (and none are more dear to me than yourself) suffer from my silence. I count with reason upon their indulgence. The tone of your excellent letters shows that I am right. You spoil me.

Your letters continue to be always warm and affectionate. I receive few like them. Since two thirds of the letters addressed to me (partly copies of letters written to the king or the ministers) remain unanswered, I am blamed, charged with being a parvenu courtier, an apostate from science. This bitterness of individual claims does not diminish my ardent desire to be useful. I act oftener than I answer. I know that I like to do good, and this consciousness gives me tranquillity in spite of my over burdened life. You are happy, my dear Aga.s.siz, in the more simple and yet truly proud position which you have created for yourself. You ought to take satisfaction in it as the father of a family, as an ill.u.s.trious savant, as the originator and source of so many new ideas, of so many great and n.o.ble conceptions.

Your admirable work on the fossil fishes draws to a close. The last number, so rich in discoveries, and the prospectus, explaining the true state of this vast publication, have soothed all irritation regarding it. It is because I am so attached to you that I rejoice in the calmer atmosphere you have thus established about you. The approaching completion of the fossil fishes delivers me also from the fear that a too great ardor might cause you irreparable losses.

You have shown not only what a talent like yours can accomplish, but also how a n.o.ble courage can triumph over seemingly insurmountable obstacles.

In what words shall I tell you how greatly our admiration is increased by this new work of yours on the Fresh-Water Fishes?

Nothing has appeared more admirable, more perfect in drawing and color. This chromatic lithography resembles nothing we have had thus far. What taste has directed the publication! Then the short descriptions accompanying each plate add singularly to the charm and the enjoyment of this kind of study. Accept my warm thanks, my dear friend. I not only delivered your letter and the copy with it to the king, but I added a short note on the merit of such an undertaking. The counselor of the Royal Cabinet writes me officially that the king has ordered the same number of copies of the Fresh-Water Fishes as of the Fossil Fishes; that is to say, ten copies. M. de Werther has already received the order. This is, to be sure, but a slight help; still, it is all that I have been able to obtain, and these few copies, with the king's name as subscriber, will always be useful to you.

I cannot close this letter without asking your pardon for some expressions, too sharp, perhaps, in my former letters, about your vast geological conceptions. The very exaggeration of my expressions must have shown you how little weight I attached to my objections. . .My desire is always to listen and to learn. Taught from my youth to believe that the organization of past times was somewhat tropical in character, and startled therefore at these glacial interruptions, I cried "Heresy!" at first. But should we not always listen to a friendly voice like yours? I am interested in whatever is printed on these topics; so, if you have published anything at all complete lately on the ensemble of your geological ideas, have the great kindness to send it to me through a book-seller. . .

Shall I tell you anything of my own poor and superannuated works?

The sixth volume is wanting to my "Geography of the Fifteenth Century" (Examen Critique). It will appear this summer. I am also printing the second volume of a new work to be ent.i.tled "Central Asia." It is not a second edition of "Asiatic Fragments," but a new and wholly different work. The thirty-five sheets of the last volume are printed, but the two volumes will only be issued together. You can judge of the difficulty of printing at Paris and correcting proofs here,--at Poretz or at Toplitz. I am just now beginning to print the first number of my physics of the world, under the t.i.tle of "Cosmos:" in German, "Ideen zur erner physischen Weltbeschreibung." It is in no sense a reproduction of the lectures I gave here. The subject is the same, but the presentation does not at all recall the form of a popular course. As a book, it has a somewhat graver and more elevated style. A "spoken book" is always a poor book, just as lectures read are poor however well prepared.

Published courses of lectures are my detestation. Cotta is also printing a volume of mine in German, "Physikalische geographische Erinnerungen." Many unpublished things concerning the volcanoes of the Andes, about currents, etc. And all this at the age when one begins to petrify! It is very rash! May this letter prove to you and to Madame Aga.s.siz that I am petrifying only at the extremities, --the heart is still warm. Retain for me the affection which I hold so dear.

A. DE HUMBOLDT.

In the following winter, or, rather, in the early days of March, 1841, Aga.s.siz visited, in company with M. Desor, the glacier of the Aar and that of Rosenlaui. He wished to examine the stakes planted the summer before on the glacier of the Aar, and to compare the winter and summer temperature within as well as without the ma.s.s of ice. But his chief object was to ascertain whether water still flowed from beneath the glaciers during the frosts of winter. This fact would have a direct bearing upon the theory which referred the melting and movement of the glaciers chiefly to their lower surface, explaining them by the central heat of the earth as their main cause. Satisfied as he was of the fallacy of this notion, Aga.s.siz still wished to have the evidence of the glacier itself.

The journey was, of course, a difficult one at such a season, but the weather was beautiful, and they accomplished it in safety, though not without much suffering. They found no water except the pure and limpid water from springs that never freeze. The glacier lay dead in the grasp of winter. The results of this journey, tables of temperature, etc., are recorded in the "Systeme Glaciaire."

In E. Desor's "Sejours dans les Glaciers" is found an interesting description of the incidents of this excursion and the appearance of the glaciers in winter. In ascending the course of the Aar they frequently crossed the shrunken river on natural snow bridges, and approaching the Handeck over fearfully steep slopes of snow they had some difficulty in finding the thread of water which was all that remained of the beautiful summer cascade. On the glacier of the Aar they found the Hotel des Neuchatelois buried in snow, while the whole surface of the glacier as well as the surrounding peaks, from base to summit, wore the same spotless mantle. The Finsteraarhorn alone stood out in bold relief, black against a white world, its abrupt slopes affording no foothold for the snow.

The scene was far more monotonous than in summer. Creva.s.ses, with their blue depths of ice, were closed; the many-voiced streams were still; the moraines and boulders were only here and there visible through the universal shroud. The sky was without a cloud, the air transparent, but the glitter of the uniform white surface was exquisitely painful to the eyes and skin, and the travelers were obliged to wrap their heads in double veils. They found the glacier of Rosenlaui less enveloped in snow than that of the Aar; and though the magnificent ice-cave, so well known to travelers for its azure tints, was inaccessible, they could look into the vault and see that the habitual bed of the torrent was dry. The journey was accomplished in a week without any untoward accident.

In the summer of 1841 Aga.s.siz made a longer Alpine sojourn than ever before. The special objects of the season's work were the internal structure of these vast moving fields of ice, the essential conditions of their origin and continued existence, the action of water within them as influencing their movement, and their own agency in direct contact with the beds and walls of the valleys they occupied. The fact of their former extension and their present oscillations might be considered as established. It remained to explain these facts with reference to the conditions prevailing within the ma.s.s itself. In short, the investigation was pa.s.sing from the domain of geology to that of physics. Aga.s.siz, who was as he often said of himself no physicist, was the more anxious to have the cooperation of the ablest men in that department, and to share with them such facilities for observation and such results as he had thus far acc.u.mulated. In addition to his usual collaborators, M. Desor and M. Vogt, he had, therefore, invited as his guest, during part of the season, the distinguished physicist, Professor James D. Forbes, of Edinburgh, who brought with him his friend, Mr. Heath, of Cambridge.* (* As the impressions of Mr.

Forbes were only made known in connection with his own later and independent researches it is unnecessary to refer to them here.) M.

Escher de la Linth took also an active part in the work of the later summer. To his working corps Aga.s.siz had added the foreman of M. Kahli, an engineer at Bienne, to whom he had confided his plans for the summer, and who furnished him with a skilled workman to direct the boring operations, a.s.sist in measurements, etc. The artist of this year was M. Jacques Burkhardt, a personal friend of Aga.s.siz, and his fellow-student at Munich, where he had spent some time at the school of art. As a draughtsman he was subsequently a.s.sociated with Aga.s.siz in his work at various times, and when they both settled in America Mr. Burkhardt became a permanent member of Aga.s.siz's household, accompanied him on his journeys, and remained with him in relations of uninterrupted and affectionate regard till his own death in 1867. He was a loyal friend and a warm-hearted man, with a thread of humor running through his dry good sense, which made him a very amusing and attractive companion.

As it was necessary, in view of his special programme of work, to penetrate below the surface of the glacier, and reach, if possible, its point of contact with the valley bottom, Aga.s.siz had caused a larger boring apparatus than had been used before, to be transported to the old site on the Aar glacier. The results of these experiments are incorporated in the "Systeme Glaciaire,"

published in 1846, with twenty-four folio plates and two maps. They were of the highest interest with reference to the internal structure and temperature of the ice and the penetrability of its ma.s.s, pervious throughout, as it proved, to air and water. On one occasion the boring-rod, having been driven to a depth of one hundred and ten feet, dropped suddenly two feet lower, showing that it had pa.s.sed through an open s.p.a.ce hidden in the depth of the ice.

The release of air-bubbles at the same time gave evidence that this glacial cave, so suddenly broken in upon, was not hermetically sealed to atmospheric influences from without.

Aga.s.siz was not satisfied with the report of his instruments from these unknown regions. He determined to be lowered into one of the so-called wells in the glacier, and thus to visit its interior in person. For this purpose he was obliged to turn aside the stream which flowed into the well into a new bed which he caused to be dug for it. This done, he had a strong tripod erected over the opening, and, seated upon a board firmly attached by ropes, he was then let down into the well, his friend Escher lying flat on the edge of the precipice, to direct the descent and listen for any warning cry.

Aga.s.siz especially desired to ascertain how far the laminated or ribboned structure of the ice (the so-called blue bands) penetrated the ma.s.s of the glacier. This feature of the glacier had been observed and described by M. Guyot (see page 292), but Mr. Forbes had called especial attention to it, as in his belief connected with the internal conditions of the glacier. It was agreed, as Aga.s.siz bade farewell to his friends on this curious voyage of discovery, that he should be allowed to descend until he called out that they were to lift him. He was lowered successfully and without accident to a depth of eighty feet. There he encountered an unforeseen difficulty in a wall of ice which divided the well into two compartments. He tried first the larger one, but finding it split again into several narrow tunnels, he caused himself to be raised sufficiently to enter the smaller, and again proceeded on his downward course without meeting any obstacle. Wholly engrossed in watching the blue bands, still visible in the glittering walls of ice, he was only aroused to the presence of approaching danger by the sudden plunge of his feet into water. His first shout of distress was misunderstood, and his friends lowered him into the ice-cold gulf instead of raising him. The second cry was effectual, and he was drawn up, though not without great difficulty, from a depth of one hundred and twenty-five feet. The most serious peril of the ascent was caused by the huge stalact.i.tes of ice, between the points of which he had to steer his way. Any one of them, if detached by the friction of the rope, might have caused his death.

He afterward said: "Had I known all its dangers, perhaps I should not have started on such an adventure. Certainly, unless induced by some powerful scientific motive, I should not advise any one to follow my example." On this perilous journey he traced the laminated structure to a depth of eighty feet, and even beyond, though with less distinctness.

The summer closed with their famous ascent of the Jungfrau. The party consisted of twelve persons Aga.s.siz, Desor, Forbes, Heath, and two travelers who had begged to join them,--M. de Chatelier, of Nantes, and M. de Pury, of Neuchatel, a former pupil of Aga.s.siz.

The other six were guides; four beside their old and tried friends, Jacob Leuthold and Johann Wahren. They left the hospice of the Grimsel on the 27th of August, at four o'clock in the morning.

Crossing the Col of the Oberaar they descended to the snowy plateau which feeds the Viescher glacier. In this grand amphitheatre, walled in by the peaks of the Viescherhorner, they rested for their midday meal. In crossing these fields of snow, while walking with perfect security upon what seemed a solid ma.s.s, they observed certain window-like openings in the snow. Stooping to examine one of them, they looked into an immense open s.p.a.ce, filled with soft blue light. They were, in fact, walking on a hollow crust, and the small window was, as they afterward found, opposite a large creva.s.se on the other side of this ice-cavern, through which the light entered, flooding the whole vault and receiving from its icy walls its exquisite reflected color.* (* The effect is admirably described by M. Desor in his account of this excursion, "Sejours dans les Glaciers" page 367.)

Once across the fields of snow and neve, a fatiguing walk of five hours brought them to the chalets of Meril,* (* Sometimes Moril, but I have retained the spelling of M. Desor.--E.C.A.) where they expected to sleep. The night which should have prepared them for the fatigue of the next day was, however, disturbed by an untoward accident. The ladder left by Jacob Leuthold when last here with Hugi in 1832, nine years before, and upon which he depended, had been taken away by a peasant of Viesch. Two messengers were sent in the course of the night to the village to demand its restoration.

The first returned unsuccessful; the second was the bearer of such threats of summary punishment from the whole party that he carried his point, and appeared at last with the recovered treasure on his back. They had, in the mean while, lost two hours. They should have been on their road at three o'clock; it was now five. Jacob warned them therefore that they must make all speed, and that any one who felt himself unequal to a forced march should stay behind. No one responded to his suggestion, and they were presently on the road.

Pa.s.sing Lake Meril, with its miniature icebergs, they reached the glacier of the Aletsch and its snow-fields, where the real difficulties and dangers of the ascent were to begin. In this great semicircular s.p.a.ce, inclosed by the Jungfrau, the Monch, and the lesser peaks of this mountain group, lies the Aletsch reservoir of snow or neve. As this spot presented a natural pause between the laborious ascent already accomplished and the immense declivities which lay before them yet to be climbed, they named it Le Repos, and halted there for a short rest. Here they left also every needless inc.u.mbrance, taking only a little bread and wine, in case of exhaustion, some meteorological instruments, and the inevitable ladder, axe, and ropes of the Alpine climber. On their left, to the west of the amphitheatre, a vast pa.s.sage opened between the Jungfrau and the Kranzberg, and in this could be distinguished a series of terraces, one above the other. The story is the usual one, of more or less steep slopes, where they sank in the softer snow or cut their steps in the icy surfaces; of open creva.s.ses, crossed by the ladder, or the more dangerous ones, masked by snow, over which they trod cautiously, tied together by the rope. But there was nothing to appall the experienced mountaineer with firm foot and a steady head, until they reached a height where the summit of the Jungfrau detached itself in apparently inaccessible isolation from all beneath or around it. To all but the guides their farther advance seemed blocked by a chaos of precipices, either of snow and ice or of rock. Leuthold remained however quietly confident, telling them he clearly saw the course he meant to follow. It began by an open gulf of unknown depth, though not too wide to be spanned by their ladder twenty-three feet in length.

On the other side of this creva.s.se, and immediately above it, rose an abrupt wall of icy snow. Up this wall Leuthold and another guide led the way, cutting steps as they went. When half way up they lowered the rope, holding one end, while their companions fastened the other to the ladder, so that it served them as a kind of hand-rail, by which to follow. At the top they found themselves on a terrace, beyond which a far more moderate slope led to the Col of Roththal, overlooking the Aletsch valley on one side, the Roththal on the other. From this point the ascent was more and more steep and very slow, as every step had to be cut. Their difficulties were increased, also, by a mist which gathered around them, and by the intense cold. Leuthold kept the party near the border of the ridge, because there the ice yielded more readily to the stroke of the axe; but it put their steadiness of nerve to the greatest test, by keeping the precipice constantly in view, except when hidden by the fog. Indeed, they could drive their alpenstocks through the overhanging rim of frozen snow, and look sheer down through the hole thus made to the amphitheatre below. One of the guides left them, unable longer to endure the sight of these precipices so close at hand. As they neared their goal they feared lest the mist might, at the last, deprive them of the culminating moment for which they had braved such dangers. But suddenly, as if touched by their perseverance, says M. Desor, the veil of fog lifted, and the summit of the Jungfrau, in its final solitude, rose before them.

There was still a certain distance to be pa.s.sed before they actually reached the base of the extreme peak. Here they paused, not without a certain hesitation, for though the summit lay but a few feet above them, they were separated from it by a sharp and seemingly inaccessible ridge. Even Aga.s.siz, who was not easily discouraged, said, as he looked up at this highest point of the fortress they had scaled "We can never reach it." For all answer, Jacob Leuthold, their intrepid guide, flinging down everything which could embarra.s.s his movements, stretched his alpenstock over the ridge as a grappling pole, and, trampling the snow as he went, so as to flatten his giddy path for those who were to follow, was in a moment on the top. To so steep an apex does this famous peak narrow, that but one person can stand on the summit at a time, nor was even this possible till the snow was beaten down. Returning on his steps, Leuthold, whose quiet, unflinching audacity of success was contagious, a.s.sisted each one to stand for a few moments where he had stood. The fog, the effect of which they had so much feared, now lent something to the beauty of the view from this sublime foothold. Ma.s.ses of vapor rolled up from the Roththal on the southwest, but, instead of advancing to envelop them, paused at a little distance arrested by some current from the plain. The temperature being below freezing point, the drops of moisture in this wall of vapor were congealed into ice-crystals, which glittered like gold in the sunlight and gave back all the colors of the rainbow.

When all the party were once more a.s.sembled at the base of the peak, Jacob, whose resources never failed, served to each one a little wine, and they rested on the snow before beginning their perilous descent. Of living things they saw only a hawk, poised in the air above their heads; of plants, a few lichens, where the surface of the rock was exposed. It was four o'clock in the afternoon before they started on their downward path, turning their faces to the icy slope, and feeling for the steps behind them, some seven hundred in all, which had been cut in ascending. In about an hour they reached the Col of the Roththal, where the greatest difficulties of the ascent had begun and the greatest dangers of the descent were over. So elated were they by the success of the day, and so regardless of lesser perils after those they had pa.s.sed through, that they were now inclined to hurry forward incautiously.

Jacob, prudent when others were rash, as he was bold when others were intimidated, constantly called them to order with his: "Hubschle! nur immer hubschle!" ("Gently! always gently!")

At six o'clock they were once more at Le Repos, having retraced their steps in two hours over a distance which had cost them six in going. Evening was now falling, but daylight was replaced by moonlight, and when they reached the glacier its whole surface shone with a soft silvery l.u.s.tre, broken here and there by the gigantic shadow of some neighboring mountain thrown black across it. At about nine o'clock, just as they had pa.s.sed that part of the glacier which was, on account of the frequent creva.s.ses, the most dangerous, they were cheered by the sound of a distant yodel. It was the call of a peasant who had been charged to meet them with provisions, at a certain distance above Lake Meril, in case they should be overcome by hunger and fatigue. The most acceptable thing he brought was his great wooden bucket, filled with fresh milk. The picture of the party, as they stood around him in the moonlight, dipping eagerly into his bucket, and drinking in turn until they had exhausted the supply, is so vivid, that one shares their good spirits and their enjoyment. Thus refreshed, they started on the last stage of their journey, three leagues of which yet lay before them, and at half-past eleven arrived at the chalets of Meril, which they had left at dawn.

On the morrow the party broke up, and Aga.s.siz and Desor, accompanied by their friend, M. Escher de la Linth, returned to the Grimsel, and after a day's rest there repaired once more to the Hotel des Neuchatelois. They remained on the glacier until the 5th of September, spending these few last days in completing their measurements, and in planting the lines of stakes across the glacier, to serve as a means of determining its rate of movement during the year, and the comparative rapidity of that movement at certain fixed points. Thus concluded one of the most eventful seasons Aga.s.siz and his companions had yet pa.s.sed upon the Alps.*

(* Though quoting his exact language only in certain instances, the account of this and other Alpine ascensions described above has been based upon M. E. Desor's "Sejours dans les Glaciers". His very spirited narratives, added to my own recollections of what I had heard from Mr. Aga.s.siz himself on the same subject, have given me my material.--E.C.A.)

CHAPTER 11.

1842-1843: AGE 35-36.

Zoological Work uninterrupted by Glacial Researches.

Various Publications.

"Nomenclator Zoologicus."

"Bibliographia Zoologiae et Geologiae."

Correspondence with English Naturalists.

Correspondence with Humboldt.

Glacial Campaign of 1842.

Correspondence with Prince de Canino concerning Journey to United States.

Fossil Fishes from the Old Red Sandstone.

Glacial Campaign of 1843.

Death of Leuthold, the Guide.

Although his glacier work was now so prominent a feature of Aga.s.siz's scientific life, his zoological studies, especially his ichthyological researches, and more especially his work on fossil fishes, went on with little interruption. His publications upon Fossil Mollusks,* (* "Etudes Critiques sur les Mollusques Fossiles"

4 numbers quarto with 100 plates.) upon Tertiary Sh.e.l.ls,* (*

"Iconographie des Coquilles Tertiaires reputees identiques sur les vivans" 1 number quarto 14 plates.) upon Living and Fossil Echinoderms,* (* "Monographie d'Echinodermes vivans et fossiles" 4 numbers quarto with 37 plates.) with many smaller monographs on special subjects, were undertaken and completed during the most active period of his glacial investigations. More surprising is it to find him, while pursuing new lines of investigation with pa.s.sionate enthusiasm, engaged at the same time upon works seemingly so dry and tedious as his "Nomenclator Zoologicus," and his "Bibliographia Zoologiae et Geologiae."

The former work, a large quarto volume with an Index,* (* The Index was also published separately as an octavo.) comprised an enumeration of all the genera of the animal kingdom, with the etymology of their names, the names of those who had first proposed them, and the date of their publication. He obtained the cooperation of other naturalists, submitting each cla.s.s as far as possible for revision to the leaders in their respective departments.

In his letter of presentation to the library of the Neuchatel Academy, addressed to M. le Baron de Chambrier, President of the Academic Council, Aga.s.siz thus describes the Nomenclator.