MEMOIR ARNOLD GUYOT. 1807-1884. BY JAMES D. DANA. READ BEFORE THK NATIONAL ACADEMY, APRIL 21, 1886. 309 BIOGRAPHICAL MEMOIR OF ARNOLD GUYOT. It is a remarkable fact in the history of American science that, forty years since, the small Republic of Switzerland lost, and America gained, three scientists who became leading men of the country in their several departments—AGASSIZ, in Zoology, GUYOT, in Physical Geography, and LESQUEREUX in Paleontological Bot- any; Agassiz coming in 1846, Guyot and Lesquereux in 1848. A fourth, Mr. L. F. DE POURTALES, who accompanied Agassiz, also merits prominent mention; for he was " the pioneer of deep- sea dredging in America."* The Society of the Natural Sciences at Neuchatel lost all four. As an Americau Academy of Sciences we cannot but rejoice in our gain ; but we may also indulge at least in a passing regret for Neuchatel, and recognize that in the life and death of Agassiz, Pourtales, and Guyot we have common in- terests and sympathies. My own acquaintance with Prof. Guyot commenced after his arrival in America, when half of his life was already passed. In preparing this sketch of our late colleague, I have therefore drawn largely from others, and chiefly from his family, and from a memo- rial address by Mr. Charles Faure, of Geneva, one of his pupils, which was published in 1884 by the Geographical Society of Geneva.")" Youth. Education in Switzerland and Germany, 1807 to 1835.— To obtain a clear insight into the character of Prof. Guyot, it is important to have in view, at the outset, the fact that the Guyot family, early in the sixteenth century, became protestants, through the preaching of the French reformer, Farel, the cotemporary of Luther; and also, the sequel to this fact, that at the revocation of the edict of Nantes, the Guyot family was one of the sixty that moved into the principality of Neuchatel and Valangin from the valleys of Pragela and Queyraz in the high Alps of Dauphiny. Thus the race was one of earnestness and high purpose, of the kind *A. Agassiz, Amor. Jour. Sci., 3d Scr., xx, 254, 1880. t Vie ot Traviuix d'Arnold Guyot, 1807-1884, par Charles Faure, 72 pp. 8vo. Head before the Geographical Society of Geneva, April 25 and August 25, 1884. 311 NATIONAL ACADEMY OP SCIENCES. and origin that contributed largely to the foundations of the Ameri- can Republic. Prof. Guyot's father, David Pierre, esteemed for his " prompt in- telligence and perfect integrity," married, in 1796, Mademoiselle Constance Favarger, of Neuchatel, "a lady of great personal beauty and rare nobility of character." Arnold Henri, one of twelve chil- dren, was born at Boudevilliers, on the 28th of September, 1807, and was named after the Swiss patriot of the fourteenth century, Arnold von Winkelried. About 1818 the family moved to Hau- terive, three miles from Neuchatel, where his father died the follow- ing year. From the house at Hauterive young Guyot had before him, to the southeastward, the whole chain of the Alps, from Mt. Blanc to Titlis; and his sensitive nature must have drawn inspira- tion from the glorious view—the same deep draughts that he at- tributed to young Agassiz, in his academic memoir of his friend, with reference to the same circumstance—the snowy Bernese Ober- land, the Jungfrau, the Schreckhorn, the Finsteraarhorn,the Eigers, and other summits to Mt. Blanc, " looming up before his eyes in the view from his house." Such views are calculated to make physical geographers and geologists of active minds. Guyot early found pleasure in the collection of insects and plants, and evinced in this and other ways the impress that nature was making upon him. Previous to the year 1818 and for a while after, Guyot was at school at La Chaux-de-Fonds, a noted village " at the foot of a narrow and savage gorge of the Jura," 3,070 feet above the sea. In 1821, then fourteen years of age, he entered the College of Neu- chatel, where he was a classmate of Leo Lesquereux, the botanist. " Guyot and I," says Lesquereux, " were, for some years, brothers in study, working iu common, and often spending our vacations together, either at Guyot's home, at Hauterive, or with -my parents at Fleurier; and I owe much in life to the good influences of this friendship." His studies were classical—Latin, Greek, and Philos- ophy—arranged for preparing a boy for the profession of the Law, Medicine, or Theology, with almost nothing to foster his love of nature. In 1825, then eighteen, he left home to complete his education in Germany. After spending three months at Metzingen, near Stutt- gart, in the study of the German language, he went to Carlsruhe where he became an inmate of the family of Mr. Braun, a man of 312 ARNOLD GUYOT. wealth and scientific tastes, the father of the distinguished botanist and philosopher, Alexander Braun, the discoverer of phyllotaxis— terms of intimacy with the family on the part of several of his rela- tives having been of long standing. The family comprised also a younger sou and two daughters. Agassiz was then a student at Heidelberg, along with young Alexander Braun and Carl Schimper, but he spent his summer vacations at the Carlsruhe mansion. A vacation soon came. " The arrival of the eldest son of the house," says Guyot, " already distinguished by his scientific publications, with his three university friends—Agassiz, Schimper, the gifted co- laborer of Braun in the discovery of phyllotaxis, and Imhoff, of Bale, the future author of one of the best Entomological Faunas of Switzer- land and Southern Germany—was a stirring event, which threw new life into the quiet circle. After a short time devoted to a mutual acquaintance, every one began to work. The acquisition of knowl- edge was the rule of the day, and social enjoyment the sweet condi- ment to more solid food." " My remembrance," remarks Guyot, " of those few months of alternate work and play, attended by so much real progress, are among the most delightful of my younger days." "Add to these attractions the charm of the society of a few select and intimate friends, professors, clergymen, and artists, drop- ping in almost every evening, and you will easily understand how congenial, how fostering to all noble impulses, must have been the atmosphere of this family for the young and happy guests assembled under its hospitable roof." " Months were thus spent in constant and immediate intercourse with nature, the subjects of investigation changing with the advancing season. Botany and entomology had their turn," and " demonstrations of phyllotaxis," he says, " now reduced to definite formula by Braun and Schimper, and shown in various plant forms, but especially in pine-cones, were of absorbing interest. The whole plan of the present animal kingdom in its relations to the extinct paleontological forms was the theme of ani- mated discussions." He adds," It would be idle to attempt to deter- mine the measure of mutual benefit derived by these young students of nature from their meeting under such favorable circumstances. It certainly was great, and we need no other proof of the strong impulse they all received from it than the new ardor with which each pursued and subsequently performed his life-work."* * Guyot's Academic Memoir of Agassiz, pp. 9-12. (24) 313 NATIONAL, ACADEMY OP SCIENCES. Guyot took in, equally with Agassiz, the newly-developed views in botany, embryology, and zoological classification that were the subjects of thought and discussion, and became profoundly impressed thereby, as his later work shows. From Carlsruhe, Guyot went to Stuttgart and took the course at the gymnasium, where he made himself a proficient in the German language. Returning to Neuchatel in 1827, and there quickened in his religious faith and feelings by the preaching of the Rev. Samuel Petit-pierre, his benevolent impulses under a sense of duty led him to turn from science to theology, and commence serious preparation for the ministry. In 1829, then 22 years of age, hav- ing this purpose still in view, he went to Berlin to attend the lectures of Schleiermacher, Neander, and Hengstenberg, and there remained for five years—1830 to 1835. In order to meet his expenses he ac- cepted the invitation of Herr Miiller, Privy Counsellor to the King of Prussia, to live with him and give his children the benefit of con- versation in French. The position brought him. into intercourse with the highest of Berlin society, and was in many ways of great benefit to him. While pursuing theology in earnest, his hours of recreation found him making collections of the plants and shells of the country, and otherwise following his scientific leadings. Humboldt introduced him to the Berlin Botanical Garden, where the plants of the tropics were a source of special gratification and profit. Moreover, other courses of lectures attracted him, as those of Hegel, of Steffens on psychology and the philosophy of nature, Mitscherlich on chemis- try, Hofmann on geology, Dove on physics and meteorology, and especially those of Carl Ritter, the eminent geographer, whose philo- sophical views were full of delight to his eager mind and touched a sympathetic cord. Under such influence he found his love for nature- science rapidly gaining possession of him; and, yielding finally to his mental demands and to his conscience, which would not permit him to enter the ministry with a divided purpose, he determined to' droj) theology and make science his chief pursuit. . Ritter, of all his Berlin teachers, made the profoundest impression on his course of thought; and his biographical sketch of him, pre- sented to the American Geographical Society in 1860, four years after his death, exhibits the admiring affection of a pupil who was like Ritter in his profounder sentiments. A paragraph from the memoir will show the tenor of Ritter's geographical teaching and 314 ARNOLD GUYOT. something of the mental affiliation between them. Guyot says (p 48): "Ritter, in the introduction to the 'Erdkunde,' declares that the fundamental idea which underlies all his work, and furnishes him a newprinciplefor arranging the well-digested materials of the science of the globe, has its deep root in the domain of faith. This idea, he adds, was derived from an inward intuition, which gradually grew out of his life in nature and among men. It could not be, before- hand, sharply defined and limited, but would become fully mani- fested in the completion of the edifice itself. That noble edifice is now before us, and, unfinished though it be, it reveals the plan of the whole and allows us clearly to perceive that fundamental idea on which it rests. It is a strong faith that our globe, like the to- tality of creation, is a great organism, the work of an all-wise Di- vine Intelligence, an admirable structure, all the parts of which are purposely shaped and arranged and mutually dependent, and, like organs, fulfill, by the will of the Maker, specific functions which combine themselves into a common life. But for Ritter that organ- ism of the globe comprises not nature only; it includes man, and, with man, the moral and intellectual life." " None before him per- ceived so clearly the hidden but strong ties which mutually bind man to nature—those close and fruitful relations between man and his dwelling place, between a continent and its inhabitants, between a country and the people which hold it as its share of the conti- nent—those influences which stamp the races and nations each with a character of their own, never to be effaced during the long period of their existence." We have here ideas that took, in Guyot, a still larger expansion. Guyot derived great profit also from the works and the friend- ship of Humboldt. His address at the Humboldt Commemoration of the American Geographical Society, in 1859, was a beautiful tribute to this model student of nature.* The five years of study at the Berlin University terminated with an examination which brought him the degree of Doctor of Philoso- phy. His graduating thesis, written in Latin, as was then the rule, was on " The Natural Classification of Lakes." To Paris, the Pyrenees, Italy, etc., 1835 to 1839.—From Berlin, * Journal of the American Geographical Society, vol. I, p. 242, October, 1859. 815 NATIONAL ACADEMY OP SCIENCES. Guyot, in his 28th year—June of 1835—went to Paris to take charge of the education of the sons of Count de Pourtales-Gorgier, and con- tinued with the family four years. Letters of introduction from Humboldt led to much intercourse with Brongniart and other sa- vants of the great city. For the summer he accompanied the family to Eaux Bonnes, in the Pyrenees. While there he made ascents of the higher peaks and took excursions in various directions—to the amphitheatre of Gavarnie, to the borders of Spain by the Pont d'Espagne and the pass beyond, to the valley of the Eaux Chaudes, etc.—in order to study the features and flora, and compare the mountains in these respects with the Alps. In the autumn he went with his pupils to Belgium, Holland, and the Rhine to study the characteristic features of these countries. The following year he visited Pisa, and there, besides enjoying the new scenes, made vari- ous barojnetrical measurements, determining the elevation of the Observatory at Florence and of other points. Trip to the Glaciers in 1838.—In the spring of 1838 Agassiz found Guyot still at Paris. During the summer preceding Agassiz had startled the scientific world by his declarations as to a Universal Glacial Era, contained in a paper read before the Helvetic Society of Natural Sciences assembled at Neuchatel. His work in 1837— prompted in 1836 by Charpentier's discoveries proving the fact of a former epoch of immense glaciers in Switzerland—had led him to the bold conclusion, and he was full of his new idea when he met his old companion. He urged Guyot, who hesitated at accepting his views without examination, to study the facts, and obtained the promise that he would visit the glaciers that summer. In his memoir of Agassiz, Guyot states that his six weeks of in- vestigation that season in the Central Alps (nearly two years before Agassiz commenced his investigations on the Glacier of the Aar) were fruitful beyond expectation. He says that, from the examina- tion of the glaciers of the Aar, Rhone, Gries, Brenva, and others, he learned (1) the law of the moraines; (2) that of the more rapid flow of the center of the glacier than the sides; (3) that of the more rapid flow of the top than the bottom ; (4) that of the laminated or ribboned structure ("blue bands"); and (5) that of the movement of the glacier by a gradual molecular displacement, instead of by a sliding of the ice-mass, as held by de Saussure. The facts and conclusions were communicated to the Geological Society of France at a meeting at Porrentruy, in September, 1838. 310 ARNOLD GUYOT. The communication is mentioned in the Bulletin of the Society for that year,* but no report of it is given because the manuscript re- mained in his hands unfinished, in consequence of his protracted illness the winter following. The portion then finished (which was withheld from publication because, by special arrangement between them, Agassiz in 1840 entered upon the special study of the glaciers and Guyot on that of the Swiss erratic phenomena, for their separate parts of a general survey) has recently been printed in Volume XIII (1883) of the Bulletin of the Neuchatel Society of Natural Sciences. In 1842 this manuscript was deposited, by motion of Agassiz, in the archives of the Neuchatel Society, and in 1848 it was withdrawn by Guyot when he left for America. It is to be regretted that pub- lication was not substituted in 1842 for burial. Its recent publica- tion was made by the request of Guyot, early in 1883, from a certified copy of the original manuscript. This paper gives the facts on which Guyot based his conclusions, and since these conclusions comprise some of the most important of the views now accepted relating to glacier motion and structure, and antedate the observations of Agassiz, Eendu, and Forbes, they have special interest. The fact of a less rapid movement of the bottom ice than the top, owing to friction, he ascertained by the observation that in glaciers of steep descent, like the Rhone at its rapids, and the Gries, the transverse crevasses and the masses they cut off are at first vertical or nearly so ; but below the rapids, where the slope is gentle and the crevasses become mostly closed, the masses are inclined with the pitch up stream, and this up-stream inclination is reduced at the termination of the glacier to a few degrees. The crevasses, although closing up below, are still traceable. He says the so-called layers are not strictly layers; but great numbers of cracks remain, which give to the mass the appearance of being made up of beds several yards thick, as may be seen in the glaciers of the Grindelwald valley, Aar, and others. Further: To this pitch in the stratification at the lower extremity, the beds rising outward, Guyot attributes also the origin of the majestic ice-chambers, whence in most cases flow great streams, as that of the Rhone, of the Arveyron at the foot of the Mer de Glace, of the Lutschinen from the glaciers of Grindelwald. * Volume IX, page 407. 317 NATIONAL ACADEMY OF SCIENCES. The more rapid movement of the centre than the sides also was learned from the Rhone glacier and others of steep descent. The crevasses, at first transverse, were found to be arched in front below the rapids, and increasingly arched to the extremity, and the successive crevasse- lines were very nearly concentric with the semicircular outline of the extremity of the glacier. He gives a figure of the Rhone glacier as seen from the Maienwand in illustration, and other later glacia- lists have appealed to the same evidence of lateral friction. The semicircular outline of the terminal moraine was found to be another result of the cause just mentioned ; and so also the "even- tail" arrangement of the several moraines immediately above the termination. The greater height and breadth of the central moraine is made a consequence of the greater velocity of the ice at the middle of the upper surface, more transportation taking place consequently in a given time. Again": The conclusion that the movement of the glacier was largely through molecular displacement was supported by his observation that the ice, instead of breaking up and rising into an accumulation of masses on its passage by an isolated rock, or rocky islet, in its course, spread around and enveloped it without fracturing; and he refers to a fine example of this at the two isolated islets of rock in the midst of the great Brenva glacier, called the eyes of the glacier." The same thing is observed "at the Jardin duTalefre, a true islet in the midst of a mer de glace, having a border of blocks of rock, or of a moraine, cast upon its sides by the march of the glacier, just like the coast dunes of an island in the ocean." In view of such facts, Guyot observes: "If it is true that the differ- ent parts of a glacier move with different velocities; if the glacier adapts itself to the form of a valley and fills all depressions without ceasing to be continuous; if it can bend around an obstacle and closely enclose it without the fracturing of its mass, like a spreading liquid, we may affirm that the movements take place through a molecular displacement, and we must abandon, at least as the only cause, the idea of a slow sliding of the mass upon itself as incom- patible with the phenomena presented.* *In French his words of 1888 are: " On pout affirmerquoces mouvements no pcuvont avoir lieu qu' en vertu d' 1111 deplacement moleeulaire, ot il faul abandonnor, au moins comme cause unique, 1' idee d' un glissement lent de la masse sur cllc memo, eomme incompatible avec les phenomenes que pres- ente la marche des glaciers." 318 ARNOLD GUYOT. The "blue bands" of the glacier were first described by Guyot. He called the structure stratification, and observed it in the ice of the summit of the glacier of Gries, at a height of about 7,500 feet. A peculiar furrowing of the surface of the ice, the furrows one or two inches broad, attracted his attention; and this result of weathering he found to have come from the unequal firmness of the layers constituting it, layers of a softer " snowy ice " alternat- ing with those of firm bluish glassy ice. The stratification was found by him to extend over hundreds of square meters, and down- ward, on the sides of crevasses, twenty to thirty feet deep, or as far down as the eye could penetrate; and it was evident that " the layers of the two sides of a crevasse were once continuous, like the strata of the opposite sides of a transverse valley." He compared the stratification to that of certain coarsely schistose limestones.* He remarks, in conclusion : " We should say that the layers were not annual layers, but rather a series made day by day from small successive snow-falls that were melted in part by the sun of the day, and covered each night by the thick frost-glazing which en- velops all the snowy summits of the high Alps."f He further observes that " these beds were evidently formed at a greater height and in a different position from that where observed." He adds, in closing his remarks on the subject: "Do the beds, at first horizontal, or at least parallel to the surface of the glacier, ac- complish, during its movement, evolutions, as yet imperfectly un- derstood, analogous to those before mentioned [that is, those occa- sioned by differences in velocity of the middle, sides, and bottom, owing to unequal friction]. This is a point which should have further examination, with observations as minute, numerous and universal as possible. Unfortunately a thick fog and threatening weather forced me to stop work before I had ascertained whether this structure was general for the whole mass of the glacier at that altitude, or whether restricted to that locality notwithstanding the proof of so large an extension of it." *His words arc: " Stratifie a la facon do certains calcaires grossierement sehistcux," and he explains it himself as implying a lamellar structure. fin the original, the words are: " On aurnit clit, non pas des couches an- nuellos, mais une serie de couches plutot journalieres de noigo tombee suc- cessivement par petites quantites, puis fondue en partie par lo solei] de la juurnee, et couverte chaque nuit de cct epais verglas qui, au debits do la region des glaces, recouvro toutes les sommites neigeuses des hautes Alpes." 319