Louis Agassiz: His Life and Correspondence

Birthplace.

Influence of his Mother.

Early Love of Natural History.

Boyish Occupations.

Domestic Education.

First School.

Vacations.

Commercial Life renounced.

College of Lausanne.

Choice of Profession.

Medical School of Zurich.

Life and Studies there.

University of Heidelberg.

Studies interrupted by Illness.

Return to Switzerland.

Occupations during Convalescence.

JEAN LOUIS RODOLPHE AGASSIZ was born May 28, 1807, at the village of Motier, on the Lake of Morat. His father, Louis Rodolphe Agassiz, was a clergyman; his mother, Rose Mayor, was the daughter of a physician whose home was at Cudrefin, on the shore of the Lake of Neuchatel.

The parsonages in Switzerland are frequently pretty and picturesque. That of Motier, looking upon the lake and sheltered by a hill which commands a view over the whole chain of the Bernese Alps, was especially so. It possessed a vineyard large enough to add something in good years to the small salary of the pastor; an orchard containing, among other trees, an apricot famed the country around for the unblemished beauty of its abundant fruit; a good vegetable garden, and a delicious spring of water flowing always fresh and pure into a great stone basin behind the house. That stone basin was Agassiz's first aquarium; there he had his first collection of fishes.* (* After his death a touching tribute was paid to his memory by the inhabitants of his birthplace. With appropriate ceremonies, a marble slab was placed above the door of the parsonage of Motier, with this inscription, "J. Louis Agassiz, celebre naturaliste, est ne dans cette maison, le 28 Mai, 1807.")

It does not appear that he had any precocious predilection for study, and his parents, who for the first ten years of his life were his only teachers, were too wise to stimulate his mind beyond the ordinary attainments of his age. having lost her first four children in infancy, his mother watched with trembling solicitude over his early years. It was perhaps for this reason that she was drawn so closely to her boy, and understood that his love of nature, and especially of all living things, was an intellectual tendency, and not simply a child's disposition to find friends and playmates in the animals about him. In later years her sympathy gave her the key to the work of his manhood, as it had done to the sports of his childhood. She remained his most intimate friend to the last hour of her life, and he survived her but six years.

Louis's love of natural history showed itself almost from infancy. When a very little fellow he had, beside his collection of fishes, all sorts of pets: birds, field-mice, hares, rabbits, guinea-pigs, etc., whose families he reared with the greatest care. Guided by his knowledge of the haunts and habits of fishes, he and his brother Auguste became the most adroit of young fishermen,-using processes all their own and quite independent of hook, line, or net. Their hunting grounds were the holes and crevices beneath the stones or in the water-washed walls of the lake shore. No such shelter was safe from their curious fingers, and they acquired such dexterity that when bathing they could seize the fish even in the open water, attracting them by little arts to which the fish submitted as to a kind of fascination. Such amusements are no doubt the delight of many a lad living in the country, nor would they be worth recording except as illustrating the unity of Agassiz's intellectual development from beginning to end. His pet animals suggested questions, to answer which was the task of his life; and his intimate study of the fresh-water fishes of Europe, later the subject of one of his important works, began with his first collection from the Lake of Morat.

As a boy he amused himself also with all kinds of handicrafts on a small scale. The carpenter, the cobbler, the tailor, were then as much developed in him as the naturalist. In Swiss villages it was the habit in those days for the trades-people to go from house to house in their different vocations. The shoemaker came two or three times a year with all his materials, and made shoes for the whole family by the day; the tailor came to fit them for garments which he made in the house; the cooper arrived before the vintage, to repair old barrels and hogsheads or to make new ones, and to replace their worn-out hoops; in short, to fit up the cellar for the coming season. Agassiz seems to have profited by these lessons as much as by those he learned from his father; and when a very little fellow, he could cut and put together a well-fitting pair of shoes for his sisters' dolls, was no bad tailor, and could make a miniature barrel that was perfectly water-tight. He remembered these trivial facts as a valuable part of his incidental education. He said he owed much of his dexterity in manipulation, to the training of eye and hand gained in these childish plays.

Though fond of quiet, in-door occupation, he was an active, daring boy. One winter day when about seven years of age, he was skating with his little brother Auguste, two years younger than himself, and a number of other boys, near the shore of the lake. They were talking of a great fair held that day at the town of Morat, on the opposite side of the lake, to which M. Agassiz had gone in the morning, not crossing upon the ice, however, but driving around the shore. The temptation was too strong for Louis, and he proposed to Auguste that they should skate across, join their father at the fair, and come home with him in the afternoon. They started accordingly. The other boys remained on their skating ground till twelve o'clock, the usual dinner hour, when they returned to the village. Mme. Agassiz was watching for her boys, thinking them rather late, and on inquiring for them among the troop of urchins coming down the village street she learned on what errand they had gone. Her anxiety may be imagined. The lake was not less than two miles across, and she was by no means sure that the ice was safe. She hurried to an upper window with a spy-glass to see if she could descry them anywhere. At the moment she caught sight of them, already far on their journey, Louis had laid himself down across a fissure in the ice, thus making a bridge for his little brother, who was creeping over his back. Their mother directed a workman, an excellent skater, to follow them as swiftly as possible. He overtook them just as they had gained the shore, but it did not occur to him that they could return otherwise than they had come, and he skated back with them across the lake. Weary, hungry, and disappointed, the boys reached the house without having seen the fair or enjoyed the drive home with their father in the afternoon.

When he was ten years old, Agassiz was sent to the college for boys at Bienne, thus exchanging the easy rule of domestic instruction for the more serious studies of a public school. He found himself on a level with his class, however, for his father was an admirable teacher. Indeed it would seem that Agassiz's own passion for teaching, as well as his love of young people and his sympathy with intellectual aspiration everywhere, was an inheritance. Wherever his father was settled as pastor, at Motier, at Orbe, and later at Concise, his influence was felt in the schools as much as in the pulpit. A piece of silver remains, a much prized heir-loom in the family, given to him by the municipality of Orbe in acknowledgment of his services in the schools.

The rules of the school at Bienne were rather strict, but the life led by the boys was hardy and invigorating, and they played as heartily as they worked. Remembering his own school-life, Agassiz often asked himself whether it was difference of climate or of method, which makes the public school life in the United States so much more trying to the health of children than the one under which he was brought up. The boys and girls in our public schools are said to be overworked with a session of five hours, and an additional hour or two of study at home. At the College of Bienne there were nine hours of study, and the boys were healthy and happy. Perhaps the secret might be found in the frequent interruption, two or three hours of study alternating with an interval for play or rest. Agassiz always retained a pleasant impression of the school and its teachers. Mr. Rickly, the director, he regarded with an affectionate respect, which ripened into friendship in maturer years.

The vacations were, of course, hailed with delight, and as Motier was but twenty miles distant from Bienne, Agassiz and his younger brother Auguste, who joined him at school a year later, were in the habit of making the journey on foot. The lives of these brothers were so closely interwoven in their youth that for many years the story of one includes the story of the other. They had everything in common, and with their little savings they used to buy books, chosen by Louis, the foundation, as it proved, of his future library.

Long before dawn on the first day of vacation the two bright, active boys would be on their homeward way, as happy as holiday could make them, especially if they were returning for the summer harvest or the autumn vintage. The latter was then, as now, a season of festivity. In these more modern days something of its primitive picturesqueness may have been lost; but when Agassiz was a boy, all the ordinary occupations were given up for this important annual business, in which work and play were so happily combined. On the appointed day the working people might be seen trooping in from neighboring cantons, where there were no vineyards, to offer themselves for the vintage. They either camped out at night, sleeping in the open air, or found shelter in the stables and outhouses. During the grape gathering the floor of the barn and shed at the parsonage of Motier was often covered in the evening with tired laborers, both men and women. Of course, when the weather was fine, these were festival days for the children. A bushel basket, heaped high with white and amber bunches, stood in the hall, or in the living room of the family, and young and old were free to help themselves as they came and went. Then there were the frolics in the vineyard, the sweet cup of must (unfermented juice of the grape), and, the ball on the last evening at the close of the merry-making.

Sometimes the boys passed their vacations at Cudrefin, with their grandfather Mayor. He was a kind old man, much respected in his profession, and greatly beloved for his benevolence. His little white horse was well known in all the paths and by-roads of the country around, as he went from village to village among the sick. The grandmother was frail in health, but a great favorite among the children, for whom she had an endless fund of stories, songs, and hymns. Aunt Lisette, an unmarried daughter, who long lived to maintain the hospitality of the old Cudrefin house and to be beloved as the kindest of maiden aunts by two or three generations of nephews and nieces, was the domestic providence of these family gatherings, where the praises of her excellent dishes were annually sung. The roof was elastic; there was no question about numbers, for all came who could; the more, the merrier, with no diminution of good cheer.

The Sunday after Easter was the great popular fete. Then every house was busy coloring Easter eggs and making fritters. The young girls and the lads of the village, the former in their prettiest dresses and the latter with enormous bouquets of artificial flowers in their hats, went together to church in the morning. In the afternoon the traditional match between two runners, chosen from the village youths, took place. They were dressed in white, and adorned with bright ribbons. With music before them, and followed by all the young people, they went in procession to the place where a quantity of Easter eggs had been distributed upon the ground. At a signal the runners separated, the one to pick up the eggs according to a prescribed course, the other to run to the next village and back again. The victory was to the one who accomplished his task first, and he was proclaimed king of the feast. Hand in hand the runners, followed as before by all their companions, returned to join in the dance now to take place before the house of Dr. Mayor. After a time the festivities were interrupted by a little address in patois from the first musician, who concluded by announcing from his platform a special dance in honor of the family of Dr. Mayor. In this dance the family with some of their friends and neighbors took part,-the young ladies dancing with the peasant lads and the young gentlemen with the girls of the village,-while the rest formed a circle to look on.

Thus, between study and recreation, the four years which Agassiz's father and mother intended he should pass at Bienne drew to a close. A yellow, time-worn sheet of foolscap, on which during the last year of his school-life he wrote his desiderata in the way of books, tells something of his progress and his aspirations at fourteen years of age. "I wish," so it runs, "to advance in the sciences, and for that I need d'Anville, Ritter, an Italian dictionary, a Strabo in Greek, Mannert and Thiersch; and also the works of Malte-Brun and Seyfert. I have resolved, as far as I am allowed to do so, to become a man of letters, and at present I can go no further: 1st, in ancient geography, for I already know all my notebooks, and I have only such books as Mr. Rickly can lend me; I must have d'Anville or Mannert; 2nd, in modern geography, also, I have only such books as Mr. Rickly can lend me, and the Osterwald geography, which does not accord with the new divisions; I must have Ritter or Malte-Brun; 3rd, for Greek I need a new grammar, and I shall choose Thiersch; 4th, I have no Italian dictionary, except one lent me by Mr. Moltz; I must have one; 5th, for Latin I need a larger grammar than the one I have, and I should like Seyfert; 6th, Mr. Rickly tells me that as I have a taste for geography he will give me a lesson in Greek (gratis), in which we would translate Strabo, provided I can find one. For all this I ought to have about twelve louis. I should like to stay at Bienne till the month of July, and afterward serve my apprenticeship in commerce at Neuchatel for a year and a half. Then I should like to pass four years at a university in Germany, and finally finish my studies at Paris, where I would stay about five years. Then, at the age of twenty-five, I could begin to write."

Agassiz's note-books, preserved by his parents, who followed the education of their children with the deepest interest, give evidence of his faithful work both at school and college. They form a great pile of manuscript, from the paper copy-books of the school-boy to the carefully collated reports of the college student, begun when the writer was ten or eleven years of age and continued with little interruption till he was eighteen or nineteen. The later volumes are of nearly quarto size and very thick, some of them containing from four to six hundred closely covered pages; the handwriting is small, no doubt for economy of space, but very clear. The subjects are physiological, pathological, and anatomical, with more or less of general natural history. This series of books is kept with remarkable neatness. Even in the boy's copy-books, containing exercises in Greek, Latin, French and German, with compositions on a variety of topics, the writing is even and distinct, with scarcely a blot or an erasure. From the very beginning there is a careful division of subjects under clearly marked headings, showing even then a tendency toward an orderly classification of facts and thoughts.

It is evident from the boyish sketch which he drew of his future plans that the hope of escaping the commercial life projected for him, and of dedicating himself to letters and learning, was already dawning. He had begun to feel the charm of study, and his scientific tastes, though still pursued rather as the pastimes of a boy than as the investigations of a student, were nevertheless becoming more and more absorbing. He was fifteen years old and the time had come when, according to a purpose long decided upon, he was to leave school and enter the business house of his uncle, Francois Mayor, at Neuchatel. He begged for a farther delay, to be spent in two additional years of study at the College of Lausanne. He was supported in his request by several of his teachers, and especially by Mr. Rickly, who urged his parents to encourage the remarkable intelligence and zeal already shown by their son in his studies. They were not difficult to persuade; indeed, only want of means, never want of will, limited the educational advantages they gave to their children.

It was decided, therefore, that he should go to Lausanne. Here his love for everything bearing on the study of nature was confirmed. Professor Chavannes, Director of the Cantonal Museum, in whom he found not only an interesting teacher, but a friend who sympathized with his favorite tastes, possessed the only collection of Natural History in the Canton de Vaud. To this Agassiz now had access. His uncle, Dr. Mathias Mayor, his mother's brother and a physician of note in Lausanne, whose opinion had great weight with M. and Mme. Agassiz, was also attracted by the boy's intelligent interest in anatomy and kindred subjects. He advised that his nephew should be allowed to study medicine, and at the close of Agassiz's college course at Lausanne the commercial plan was finally abandoned, and he was permitted to choose the medical profession as the one most akin to his inclination.

Being now seventeen years of age, he went to the medical school of Zurich. Here, for the first time, he came into contact with men whose instruction derived freshness and vigor from their original researches. He was especially indebted to Professor Schinz, a man of learning and ability, who held the chair of Natural History and Physiology, and who showed the warmest interest in his pupil's progress. He gave Agassiz a key to his private library, as well as to his collection of birds. This liberality was invaluable to one whose poverty made books an unattainable luxury. Many an hour did the young student pass at that time in copying books which were beyond his means, though some of them did not cost more than a dollar a volume. His brother Auguste, still his constant companion, shared this task, a pure labor of love with him, for the books were more necessary to Louis's studies than to his own.

During the two years passed by Agassiz in Zurich he saw little of society beyond the walls of the university. His brother and he had a pleasant home in a private house, where they shared the family life of their host and hostess. In company with them, Agassiz made his first excursion of any importance into the Alps. They ascended the Righi and passed the night there. At about sunset a fearful thunder-storm gathered below them, while on the summit of the mountain the weather remained perfectly clear and calm. Under a blue sky they watched the lightning, and listened to the thunder in the dark clouds, which were pouring torrents of rain upon the plain and the Lake of Lucerne. The storm lasted long after night had closed in, and Agassiz lingered when all his companions had retired to rest, till at last the clouds drifted softly away, letting down the light of moon and stars on the lake and landscape. He used to say that in his subsequent Alpine excursions he had rarely witnessed a scene of greater beauty.

Such of his letters from Zurich as have been preserved have only a home interest. In one of them, however, he alludes to a curious circumstance, which might have changed the tenor of his life. He and his brother were returning on foot, for the vacation, from Zurich to their home which was now in Orbe, where their father and mother had been settled since 1821. Between Neuchatel and Orbe they were overtaken by a traveling carriage. A gentleman who was its sole occupant invited them to get in, made them welcome to his lunch, talked to them of their student life, and their future plans, and drove them to the parsonage, where he introduced himself to their parents. Some days afterward M. Agassiz received a letter from this chance acquaintance, who proved to be a man in affluent circumstances, of good social position, living at the time in Geneva. He wrote to M. Agassiz that he had been singularly attracted by his elder son, Louis, and that he wished to adopt him, assuming henceforth all the responsibility of his education and his establishment in life. This proposition fell like a bomb-shell into the quiet parsonage. M. Agassiz was poor, and every advantage for his children was gained with painful self-sacrifice on the part of both parents. How then refuse such an opportunity for one among them, and that one so gifted? After anxious reflection, however, the father, with the full concurrence of his son, decided to decline an offer which, brilliant as it seemed, involved a separation and might lead to a false position. A correspondence was kept up for years between Louis and the friend he had so suddenly won, and who continued to interest himself in his career. Although it had no sequel, this incident is mentioned as showing a kind of personal magnetism which, even as child and boy, Agassiz unconsciously exercised over others.

From Zurich, Agassiz went to the University of Heidelberg, where we find him in the spring of 1826.

TO HIS FATHER.

HEIDELBERG, April 24, 1826.

. . .Having arrived early enough to see something of the environs before the opening of the term, I decided to devote each day to a ramble in one direction or another, in order to become familiar with my surroundings. I am the more glad to have done this as I have learned that after the lectures begin there will be no further chance for such interruptions, and we shall be obliged to stick closely to our work at home.

Our first excursion was to Neckarsteinach, two and a half leagues from here. The road follows the Neckar, and at certain places rises boldly above the river, which flows between two hills, broken by rocks of the color of red chalk, which often jut out from either side. Farther on the valley widens, and a pretty rising ground, crowned by ruins, suddenly presents itself in the midst of a wide plain, where sheep are feeding. Neckarsteinach itself is only a little village, containing, however, three castles, two of which are in ruins. The third is still inhabited, and commands a magnificent view. In the evening we returned to Heidelberg by moonlight.

Another day we started for what is here called "The Mountain," though it is at most no higher than Le Suchet. As the needful supplies are not to be obtained there, we took our provisions with us. We had so much fun out of this, that I must tell you all about it. In the morning Z-bought at the market veal, liver, and bacon enough to serve for three persons during two days. To these supplies we added salt, pepper, butter, onions, bread, and some jugs of beer. One of us took two saucepans for cooking, and some alcohol. Arrived at the summit of our mountain, we looked out for a convenient spot, and there we cooked our dinner. It did not take long, nor can I say whether all was done according to the rules of art. But this I know,-that never did a meal seem to me better. We wandered over the mountain for the rest of the day, and at evening came to a house where we prepared our supper after the same fashion, to the great astonishment of the assembled household, and especially of an old woman who regretted the death of her husband, because she said it would certainly have amused him. We slept on the ground on some straw, and returned to Heidelberg the next day in time for dinner. The following day we went to Mannheim to visit the theatre. It is very handsome and well appointed, and we were fortunate in happening upon an excellent opera. Beyond this, I saw nothing of Mannheim except the house of Kotzebue and the place where Sand was beheaded.

To-day I have made my visits to the professors. For three among them I had letters from Professors Schinz and Hirzel. I was received by all in the kindest way. Professor Tiedemann, the Chancellor, is a man about the age of papa and young for his years. He is so well-known that I need not undertake his panegyric here. As soon as I told him that I brought a letter from Zurich, he showed me the greatest politeness, offered me books from his library; in one word, said he would be for me here what Professor Schinz, with whom he had formerly studied, had been for me in Zurich. After the opening of the term, when I know these gentlemen better, I will tell you more about them. I have still to describe my home, chamber, garden, people of the house, etc.

The next letter fills in this frame-work.

TO HIS FATHER.

HEIDELBERG, May 24, 1826.

. . .According to your request, I am going to write you all possible details about my host, the employment of my time, etc., etc. Mr.-, my "philister," is a tobacco merchant in easy circumstances, having a pretty house in the faubourg of the city. My windows overlook the town, and my prospect is bounded by a hill situated to the north of Heidelberg. At the back of the house is a large and fine garden, at the foot of which is a very pretty summer-house. There are also several clumps of trees in the garden, and an aviary filled with native birds. . .

Since each day in term time is only the repetition of every other, the account of one will give an idea of all, especially as I follow with regularity the plan of study I have formed. Every morning I rise at six o'clock, dress, and breakfast. At seven I go to my lectures, given during the morning in the Museum building, next to which is the anatomical laboratory. If, in the interval, I have a free hour, as sometimes happens from ten to eleven, I occupy it in making anatomical preparations. I shall tell you more of that and of the Museum another time. From twelve to one I practice fencing. We dine at about one o'clock, after which I walk till two, when I return to the house and to my studies till five o'clock. From five to six we have a lecture from the renowned Tiedemann. After that, I either take a bath in the Neckar or another walk. From eight to nine I resume my special work, and then, according to my inclination, go to the Swiss club, or, if I am tired, to bed. I have my evening service and talk silently with you, believing that at that hour you also do not forget your Louis, who thinks always of you. . .As soon as I know, for I cannot yet make an exact estimate, I will write you as nearly as possible what my expenses are likely to be. Sometimes there may be unlooked-for expenditures, as, for instance, six crowns for a matriculation paper. But be assured that at all events I shall restrict myself to what is absolutely necessary, and do my best to economize. The same of the probable duration of my stay in Heidelberg; I shall certainly not prolong it needlessly. . .

Now for the first time the paths of the two brothers separated, Auguste returning from Zurich to Neuchatel, where he entered into business. It chanced, however, that in one of the first acquaintances made by Louis in Heidelberg he found not only a congenial comrade, but a friend for life, and in after years a brother. Professor Tiedemann, by whom Agassiz had been so kindly received, recommended him to seek the acquaintance of young Alexander Braun, an ardent student, and an especial lover of botany. At Tiedemann's lecture the next day Agassiz's attention was attracted by a young man who sat next him, and who was taking very careful notes and illustrating them. There was something very winning in his calm, gentle face, full of benevolence and intelligence. Convinced by his manner of listening to the lecture and transcribing it that this was the student of whom Tiedemann had spoken, Agassiz turned to his neighbor as they both rose at the close of the hour, and said, "Are you Alex Braun?" "Yes, and you, Louis Agassiz?" It seems that Professor Tiedemann, who must have had a quick eye for affinities in the moral as well as in the physical world, had said to Braun also, that he advised him to make the acquaintance of a young Swiss naturalist who had just come, and who seemed full of enthusiasm for his work. The two young men left the lecture-room together, and from that time their studies, their excursions, their amusements, were undertaken and pursued in each other's company. In their long rambles, while they collected specimens in their different departments of Natural History, Braun learned zoology from Agassiz, and he, in his turn, learned botany from Braun. This was, perhaps, the reason why Alexander Braun, afterward Director of the Botanical Gardens in Berlin, knew more of zoology than other botanists, while Agassiz himself combined an extensive knowledge of botany with his study of the animal kingdom. That the attraction was mutual may be seen by the following extract from a letter of Alexander Braun to his father.

BRAUN To HIS FATHER.

HEIDELBERG, May 12, 1826.

. . .In my leisure hours, between the forenoon and afternoon lectures, I go to the dissecting-room, where, in company with another young naturalist who has appeared like a rare comet on the Heidelberg horizon, I dissect all manner of beasts, such as dogs, cats, birds, fishes, and even smaller fry, snails, butterflies, caterpillars, worms, and the like. Beside this, we always have from Tiedemann the very best books for reference and comparison, for he has a fine library, especially rich in anatomical works, and is particularly friendly and obliging to us.

In the afternoon from two to three I attend Geiger's lectures on pharmaceutical chemistry, and from five to six those of Tiedemann on comparative anatomy. In the interval, I sometimes go with this naturalist, so recently arrived among us (his name is Agassiz, and he is from Orbe), on a hunt after animals and plants. Not only do we collect and learn to observe all manner of things, but we have also an opportunity of exchanging our views on scientific matters in general. I learn a great deal from him, for he is much more at home in zoology than I am. He is familiar with almost all the known mammalia, recognizes the birds from far off by their song, and can give a name to every fish in the water. In the morning we often stroll together through the fish market, where he explains to me all the different species. He is going to teach me how to stuff fishes, and then we intend to make a collection of all the native kinds. Many other useful things he knows; speaks German and French equally well, English and Italian fairly, so that I have already appointed him to be my interpreter on some future vacation trip to Italy. He is well acquainted with ancient languages also, and studies medicine besides. . .

A few lines from Braun to his mother, several weeks later, show that this first enthusiasm, poured out with half-laughing extravagance to his father, was ripening into friendship of a more serious character.

BRAUN TO HIS MOTHER.

HEIDELBERG, June 1, 1826.

. . .I am very happy now that I have found some one whose occupations are the same as mine. Before Agassiz came I was obliged to make my excursions almost always alone, and to study in hermit-like isolation. After all, two people working together can accomplish far more than either one can do alone. In order, for instance, to utilize the interval spent in the time-consuming and mechanical work of preparing specimens, pinning insects and the like, we have agreed that while one is so employed the other shall read aloud. In this way we shall go through various works on physiology, anatomy, and zoology.

Next to Alexander Braun, Agassiz's most congenial companion at Heidelberg was Karl Schimper, a friend of Braun, and like him a young botanist of brilliant promise. The three soon became inseparable. Agassiz had many friends and companions at the university beside those who, on account of their influence upon his after life, are mentioned here. He was too affectionate not to be a genial companion among his young countrymen of whom there were many at Heidelberg, where they had a club and a gymnasium of their own. In the latter, Agassiz bore his part in all the athletic sports, being distinguished both as a powerful gymnast and an expert fencer.

Of the professors then at Heidelberg, Leuckart, the zoologist, was, perhaps, the most inspiriting. His lectures were full of original suggestions and clever hypotheses, which excited and sometimes amused his listeners. He knew how to take advantage of the enthusiasm of his brighter pupils, and, at their request, gave them a separate course of instruction on special groups of animals; not without some personal sacrifice, for these extra lectures were given at seven o'clock in the morning, and the students were often obliged to pull their professor out of bed for the purpose. The fact that they did so shows at least the friendly relation existing between teacher and scholars. With Bischoff the botanist also, the young friends were admitted to the most kindly intercourse. Many a pleasant botanical excursion they had with him, and they owed to him a thorough and skillful instruction in the use of the microscope, handled by him like a master. Tiedemann's lectures were very learned, and Agassiz always spoke of his old teacher in comparative anatomy and physiology with affectionate respect and admiration. He was not, however, an inspiring teacher, and though an excellent friend to the students, they had no such intimate personal relations with him as with Leuckart and Bischoff. From Bronn, the paleontologist, they received an immense amount of special information, but his instruction was minute in details rather than suggestive in ideas; and they were glad when their professor, finding that the course must be shortened for want of time, displayed to them his magnificent collection of fossils, and with the help of the specimens, developed his subject in a more general and practical way.* (* This collection was purchased in 1859 by the Museum of Comparative Zoology in Cambridge, Massachusetts, and Agassiz had thus the pleasure of teaching his American pupils from the very collection in which he had himself made his first important paleontological studies.) Of the medical professors, Nageli was the more interesting, though the reputation of Chelius brought him a larger audience. If there was however any lack of stimulus in the lecture rooms, the young friends made good the deficiency by their own indefatigable and intelligent study of nature, seeking to satisfy their craving for knowledge by every means within their reach.* (* The material for this account of the student life of the two friends at Heidelberg and of their teachers was chiefly furnished by Alexander Braun himself at the close of his own life, after the death of Agassiz. The later sketches of the Professors at Munich in 1832 were drawn in great part from the same source.)

As the distance and expense made it impossible for Agassiz to spend his vacations with his family in Switzerland, it soon became the habit for him to pass the holidays with his new friend at Carlsruhe. For a young man of his tastes and acquirements a more charming home-life than the one to which he was here introduced can hardly be imagined. The whole atmosphere was in harmony with the pursuits of the students. The house was simple in its appointments, but rich in books, music, and in all things stimulating to the thought and imagination. It stood near one of the city gates which opened into an extensive oak forest, in itself an admirable collecting ground for the naturalist. At the back certain rooms, sheltered by the spacious garden from the noise of the street, were devoted to science. In the first of these rooms the father's rich collection of minerals was arranged, and beyond this were the laboratories of his sons and their friends, where specimens of all sorts, dried and living plants, microscopes and books of reference, covered the working tables. Here they brought their treasures; here they drew, studied, dissected, arranged their specimens; here they discussed the theories, with which their young brains were teeming, about the growth, structure, and relations of animals and plants.* (* See "Biographical Memoir of Louis Agassiz" by Arnold Guyuot, in the "Proceedings of U.S. National Academy".)

From this house, which became a second home to Agassiz, he wrote to his father in the Christmas holidays of 1826:. . ."My happiness would be perfect were it not for the painful thought which pursues me everywhere, that I live on your privations; yet it is impossible for me to diminish my expenses farther. You would lift a great weight from my heart if you could relieve yourself of this burden by an arrangement with my uncle at Neuchatel. I am confident that when I have finished my studies I could easily make enough to repay him. At all events, I know that you cannot pay the whole at once, and therefore in telling me frankly what are our resources for this object you would do me the greatest favor. Until I know that, I cannot be at peace. Otherwise, I am well, going on as usual, always working as hard as I can, and I believe all the professors whose lectures I attend are satisfied with me.". . .His father was also pleased with his conduct and with his progress, for about this time he writes to a friend, "We have the best possible news of Louis. Courageous, industrious, and discreet, he pursues honorably and vigorously his aim, namely, the degree of Doctor of Medicine and Surgery."

In the spring of 1827 Agassiz fell ill of a typhus fever prevalent at the university as an epidemic. His life was in danger for many days. As soon as he could be moved, Braun took him to Carlsruhe, where his convalescence was carefully watched over by his friend's mother. Being still delicate he was advised to recruit in his native air, and he returned to Orbe, accompanied by Braun, who did not leave him till he had placed him in safety with his parents. The following extracts from the correspondence between himself and Braun give some account of this interval spent at home.

AGASSIZ TO BRAUN.

ORBE, May 26, 1827.

. . .Since I have been here, I have walked faithfully and have collected a good number of plants which are not yet dry. I have more than one hundred kinds, about twenty specimens of each. As soon as they can be taken out of the press, I'll send you a few specimens of each kind with a number attached so that you may identify them. Take care that you do not displace the numbers in opening the package. Should you want more of any particular kind let me know; also whether Schimper wishes for any. . .At Neuchatel I had the good fortune to find at least thirty specimens of Bombinator obstetricans with the eggs. Tell Dr. Leuckart that I will bring him some,-and some for you also. I kept several alive laid in damp moss; after fourteen days the eggs were almost as large as peas, and the little tadpoles moved about inside in all directions. The mother stripped the eggs from her legs, and one of the little tadpoles came out, but died for want of water. Then I placed the whole mass of eggs in a vessel filled with water, and behold! in about an hour some twenty young ones were swimming freely about. I shall spare no pains to raise them, and I hope, if I begin aright, to make fine toads of them in the end. My oldest sister is busy every day in making drawings for me to illustrate their gradual development. . .I dissect now as much and on as great a variety of subjects as possible. This makes my principal occupation. I am often busy too with Oken. His "Natur-philosophie" gives me the greatest pleasure. I long for my box, being in need of my books, which, no doubt, you have sent. Meantime, I am reading something of Universal History, and am not idle, as you see. But I miss the evenings with you and Schimper at Heidelberg, and wish I were with you once more. I am afraid when that happy time does come, it will be only too short. . .

BRAUN TO AGASSIZ.

HEIDELBERG, May, 1827.

. . .On Thursday evening, the 10th, I reached Heidelberg. The medical lectures did not begin till the second week of May, so that I have missed little, and almost regret having returned so soon. . . I passed the last afternoon in Basel very pleasantly with Herr Roepper, to whom I must soon write. He gave me a variety of specimens, showed me many beautiful things, and told me much that was instructive. He is a genuine and excellent botanist, and no mere collector like the majority. Neither is he purely an observer like Dr. Bischoff, but a man who thinks. . .Dr. Leuckart is in raptures about the eggs of the "Hebammen Krote," and will raise them. . .Schweiz takes your place in our erudite evening meetings. I have been lecturing lately on the metamorphosis of plants, and Schimper has propounded an entirely new and very interesting theory, which will, no doubt, find favor with you hereafter, about the significance of the circular and longitudinal fibres in organisms. Schimper is fruitful as ever in poetical and philosophical ideas, and has just now ventured upon a natural history of the mind. We have introduced mathematics also, and he has advanced a new hypothesis about comets and their long tails. . . Our chief botanical occupation this summer is the careful observation of all our plants, even the commonest, and the explanation of whatever is unusual or enigmatical in their structure. We have already cracked several such nuts, but many remain to be opened. All such puzzling specimens are spread on single sheets and set aside. . .But more of this when we are together again. . .Dr. Leuckart begs you to study carefully the "Hebammen Unke;"* (* Bombinator obstetricans referred to in a former letter.) to notice whether the eggs are already fecundated when they are in the earth, or whether they copulate later in the water, or whether the young are hatched on land, and what is their tadpole condition, etc. All this is still unknown. . .

AGASSIZ TO BRAUN.

ORBE, June 10, 1827.

. . .Last week I made a very pleasant excursion. You will remember that I have often spoken to you of Pastor Mellet at Vallorbe, who is much interested in the study of the six-legged insects. He invited me to go to Vallorbe with him for some days, and I passed a week there, spending my time most agreeably. We went daily on a search after insects; the booty was especially rich in beetles and butterflies. . .I examined also M. Mellet's own most excellent collection of beetles and butterflies very carefully. He has many beautiful things, but almost exclusively Swiss or French, with a few from Brazil,-in all about 3,000 species. He gave me several, and promises more in the autumn. . .He knows his beetles thoroughly, and observes their habits, haunts, and changes (as far as he can) admirably well. It is a pity though that while his knowledge of species is so accurate, he knows nothing of distribution, classification, or general relations. I tried to convince him that he ought to collect snails, slugs, and other objects of natural history, in the hope that he might gain thereby a wider insight. But he would not listen to it; he said he had enough to do with his Vermine.

My brother writes me that my box has arrived in Neuchatel. As I am going there soon I will take it then. I rejoice in the thought of being in Neuchatel, partly on account of my brother, Arnold (Guyot), and other friends, and partly that I may study the fishes of our Swiss lakes. The species Cyprinus and Corregonus with their allies, including Salmo, are, as you know, especially difficult. I will preserve some small specimens in alcohol, and, if possible, dissect one of each, in order to satisfy myself as to their identity or specific variety. As the same kinds have received different names in different lakes, and since even differences of age have led to distinct designations, I will note all this down carefully. When I have made it clear to myself, I will send you a catalogue of the kinds we possess, specifying at the same time the lakes in which they occur. As I am on the chapter of fishes, I will ask you:

1. What are the gill arches? 2. What the gill blades? 3. What is the bladder in fishes? 4. What is the cloaca in the egg-laying animals? 5. What signify the many fins of fishes? 6. What is the sac which surrounds the eggs in Bombinator obstetricans?

. . .Tell Dr. Leuckart I have already put aside for him the

Corregonus umbla (if such it be), but can get no Silurus glanis.

I suppose you continue to come together now and then in the evening . . .Make me a sharer in your new discoveries. Have you finished your essay on the physiology of plants, and what do you make of it?. . .

BRAUN TO AGASSIZ.

CARLSRUHE, Whitsuntide, Monday, 1827.

. . .I am in Carlsruhe, and as the package has not gone yet, I add a note. I have been analyzing and comparing all sorts of plants in our garden to-day, and I wish you had been with me. On my last sheet I send some nuts for you to pick, some wholly, some half, others not at all, cracked. Schimper is lost in the great impenetrable world of suns, with their planets, moons, and comets; he soars even into the region of the double stars, the milky way, and the nebulae.

On a loose sheet come the "nuts to pick." It contains a long list of mooted questions, a few of which are given here to show the exchange of thought between Agassiz and his friend, the one propounding zoological, the other botanical, puzzles. Although most of the problems were solved long ago, it is not uninteresting to follow these young minds in their search after the laws of structure and growth, dimly perceived at first, but becoming gradually clearer as they go on. The very first questions hint at the law of Phyllotaxis, then wholly unknown, though now it makes a part of the most elementary instruction in botany.* (* Botany owes to Alexander Braun and Karl Schimper the discovery of this law, by which leaves, however crowded, are so arranged around the stem as to divide the space with mathematical precision, thus giving to each leaf its fair share of room for growth.)

"1. Where is the first diverging point of the stems and roots in plants, that is to say, the first geniculum?

"2. How do you explain the origin of those leaves on the stem which, not arising from distinct geniculi, are placed spirally or scattered around the stem?

"3. Why do some plants, especially trees (contrary to the ordinary course of development in plants), blossom before they have put forth leaves? (Elm-trees, willow-trees, and fruit-trees.)

"4. In what succession does the development of the organs of the flower take place?-and their formation in the bud? (Compare Campanula, Papaver.)

"5. What are the leaves of the Spergula?

"6. What are the tufted leaves of various pine-trees? (Pinus sylvestris, Strobus, Larix, etc.). . .

"8. What is individuality in plants?"

The next letter contains Agassiz's answer to Dr. Leuckart's questions concerning the eggs he had sent him, and some farther account of his own observations upon them.

AGASSIZ TO BRAUN.

NEUCHATEL, June 20, 1827.

. . .Now you shall hear what I know of the "Hebammen Krote." How the fecundation takes place I know not, but it must needs be the same as in other kinds of the related Bombinator; igneus throws out almost as many eggs hanging together in clusters as obstetricans; fuscus throws them out from itself in strings (see Roseld's illustration). . .I have now carefully examined the egg clusters of obstetricans; all the eggs are in one string and hang together. This string is a bag, in which the eggs lie inclosed at different distances, though they seem in the empty space to be fallen, thread-like, together. But if you stretch the thread and press the eggs, they change their places, and you can distinctly see that they lie free in the bag, having their own membranous envelopes corresponding to those of other batrachian eggs. Surely this species seeks the water at the time of fecundation, for so do all batrachians, the water being indeed a more fitting medium for fecundation than the air. . .It is certain that the eggs were already fecundated when we found them in the ground, for later, I found several not so far advanced as those you have, and yet after three weeks I had tadpoles from them. In those eggs which were in the lowest stage of development (how they may be earlier, nescio), nothing was clearly visible; they were simply little yellow balls. After some days, two small dark spots were to be seen marking the position of the eyes, and a longitudinal streak indicated the dorsal ridge. Presently everything became more distinct; the mouth and the nasal opening, the eyes and the tail, which lay in a half circle around the body; the skin was so transparent that the beating of the heart and the blood in the vessels could be easily distinguished; the yolk and the yolk sac were meanwhile sensibly diminished. The movements of the little animal were now quite perceptible,-they were quick and by starts. After three or four weeks the eggs were as large as peas; the bags had burst at the spots where the eggs were attached, and the little creatures filled the egg envelopes completely. They moved incessantly and very quickly. Now the female stripped off the eggs from her legs; she seemed very uneasy, and sprang about constantly in the tank, but grew more quiet when I threw in more water. The eggs were soon free, and I laid them in a shallow vessel filled with fresh water. The restlessness among them now became greater, and behold! like lightning, a little tadpole slipped out of its egg, paused astonished, gazed on the greatness of the world, made some philanthropic observations, and swam quickly away. I gave them fresh water often, and tender green plants as well as bread to eat. They ate eagerly. Up to this time their different stages of development had been carefully drawn by my sister. I now went to Vallorbe; they promised at home to take care of my young brood, but when I returned the tadpoles had been forgotten, and I found them all dead; not yet decayed, however, and I could therefore preserve them in alcohol. The gills I have never seen, but I will watch to see whether they are turned inward. . .

BRAUN TO AGASSIZ.

CARLSRUHE, August 9, 1827.

. . .This is to tell you that I have determined to leave Heidelberg in the autumn and set forth on a pilgrimage to Munich, and that I invite you to be my traveling companion. Judging by a circumstantial letter from Dollinger, the instruction in the natural sciences leaves nothing to be desired there. Add to this that the lectures are free, and the theatre open to students at twenty-four kreutzers. No lack of advantages and attractions, lodgings hardly more expensive than at Heidelberg, board equally cheap, beer plenty and good. Let all this persuade you. We shall hear Gruithuisen in popular astronomy, Schubert in general natural history, Martius in botany, Fuchs in mineralogy, Seiber in mathematics, Starke in physics, Oken in everything (he lectures in winter on the philosophy of nature, natural history, and physiology). The clinical instruction will be good. We shall soon be friends with all the professors. The library contains whatever is best in botany and zoology, and the collections open to the public are very rich. It is not known whether Schelling will lecture, but at all events certain of the courses will be of great advantage. Then little vacation trips to the Salzburg and Carinthian Alps are easily made from there! Write soon whether you will go and drink Bavarian beer and Schnapski with me, and write also when we are to see you in Heidelberg and Carlsruhe. Remind me then to tell you about the theory of the root and poles in plants. As soon as I have your answer we will bespeak our lodgings from Dollinger, who will attend to that for us. Shall we again house together in one room, or shall we have separate cells in one comb, namely, under the same roof? The latter has its advantages for grass-gatherers and stone-cutters like ourselves. . .Hammer away industriously at all sorts of rocks. I have collected at Auerbach, Weinheim, Wiesloch, etc. But before all else, observe carefully and often the wonderful structure of plants, those lovely children of the earth and sky. Ponder them with child-like mind, for children marvel at the phenomena of nature, while grown people often think themselves too wise to wonder, and yet they know little more than the children. But the thoughtful student recognizes the truth of the child's feeling, and with his knowledge of nature his wonder does but grow more and more. . .