Skip to main content

Professor Of The World’s Wonders

May 2024
18min read

Everything interested Louis Agassiz, from tiny fish to gigantic glaciers, and he transmitted his enthusiasm to the students of a whole generation

Louis Agassiz, the enthusiastic Swiss naturalist, appeared on the American scene at exactly the right time and place. The place was Boston, the time, the mid-nineteenth century. Science was beginning to challenge religious concepts long held sacred. Public attention was increasingly directed toward scientific advance and toward the study of nature. Now came Agassiz, the scientist “with the Gallic power of pleasing,” to demonstrate that the physical world was full of wonders and undiscovered secrets. It was just the thing that practical, intelligent young Americans were seeking: a new frontier—a glacial theory, expeditions to Brazil, mountain peaks to scale, and ocean depths to plumb. Agassiz was eager to teach, and he found an America eager to be taught.

It was as a scientist of recognized brilliance that Agassiz came to the United States in 1846. Just under forty, he had written and published his Recherches sur les poissons fossiles more than ten years before. He had received a doctorate in zoology in 1829 and a medical degree in 1830. At twenty five he was appointed lecturer and curator at the University of Neuchâtel, and during the fourteen years he was there, the small Swiss institution had become a major scientific center. By the time he left Switzerland, Agassiz had about 175 publications to his credit, including twenty books with some two thousand excellent plates. He had already formulated his revolutionary glacial hypothesis, having become infected with the idea of an ice age, a whole pre-historic continent under a sheet of ice—powerful, inexorable, carrying great jagged rocks upon its surface, and grinding rock to pebbles and sand beneath it.

King Friedrich Wilhelm IV of Prussia, continuing his predecessor’s support of Agassiz, now awarded the scientist sufficient funds to travel to America and continue his work on glaciers. Agassiz went, and with the aid of Charles Lyell, an eminent English geologist, soon obtained the esteemed Lowell lectureship at Harvard. It was his first public appearance in this country, and at once he captured the popular imagination.

“Plan of the Creation, especially in the Animal Kingdom” was the name of the series of lectures he gave for the Lowell Institute, and the scope suggested by the title was typical of the man. He demonstrated what were then new ideas concerning the great age of the earth, using his studies of marine fossils to demonstrate the long passage of time and his observations of Alpine glaciers to prove his point. Some clergymen denounced him for extending the seven days of Genesis to the eras of geological time—but there was no shorter road to fame than to be denounced in Boston.

To the over-capacity crowds that flocked to hear him in Boston and all along the eastern seaboard, Agassiz spoke with a strong foreign accent, one of the many fables about him being that he had learned just enough English to deliver his lectures. This was not strictly true. He never would abandon his accent, however, being too much the born showman not to realize that to Americans it was part of his charm.

Agassiz looked more like a Swiss mountaineer than the learned professor that he was. Describing his first encounter with Louis Agassiz, Longfellow wrote of “a pleasant, voluble man with a bright, beaming face.” And later, after they had become close friends, Longfellow said that Agassiz had “a laugh the Puritans forgot.” It was when they were both on a lecture tour and met in Charleston, South Carolina, that Thackeray described Agassiz as “a delightful bonhommious person, as frank and unpretending as he is learned and illustrious.” In the course of his investigations of Alpine glaciers, he and his associates had climbed the Jungfrau, claiming to have been the first to do so. With boyish frankness, he boasted to his new American friends that he had scarcely ever been ill, that he could carry a man on his back “and at the same time one under each arm,” and that he could “lift an anvil that the smith could not.”
From the moment he set foot on American soil, Agassiz regarded his stay in the United States as an educational mission. His introduction to Harvard was the occasion for his scathing remark that the university was no better than a preparatory school in Europe and that students there acted like spoiled children. His philosophy of education, both as preached and practiced, was strikingly opposed to that generally in use. “My intention,” he stated some years later, “is not, however, to impart information, but to throw the burden of study on you. If I succeed in teaching you to observe, my aim will be attained.” He extended this philosophy beyond the classroom, urging it on all with whom he came in contact.

And the results were no less exciting than the philosophy. People from all walks of life wanted to show Agassiz what they had seen, what they had observed. At Nahant, just north of Boston, where Agassiz eventually had a marine laboratory, fishermen would row long distances after selling the day’s catch—just to bring him some strange specimen they had found in their nets. “Come in, come in and sit down,” Agassiz would exclaim, delighted with the gift. If the fish were well known to him he would tell the fisherman strange facts about it; if the specimen proved new he would share with the fisherman the thrill of scientific discovery.

Strolling one day into the classroom of a young teacher at a country academy, Agasssiz remarked that he needed fresh-laid turtle eggs in order to complete a study in embryology. The young teacher promptly promised to find some and at once began haunting a nearby lake every morning at dawn. It was on a Sunday, and there were no passenger trains, when the young man finally caught a turtle in the act of laying and stole the eggs. He flagged a freight and after many hazards arrived at Agassiz’s door in Cambridge very early in the morning. In answer to his ring, down the stairs came Agassiz, still in his nightshirt, to greet the amateur scientist with enthusiastic praise. The gift of sharing enthusiasm made Louis Agassiz a hero to the young man who watched entranced as the professor dissected one of the eggs, discoursing all the while on the value of the gift. “No one,” a pupil said of Agassiz, “could stand before his words and his smile.”

Agassiz’s gift of persuasion had been early developed in pleading with his father, a Swiss Protestant clergyman, for permission to study natural history. His father was Louis’ only teacher until he was ten years old. By that time, the boy could read, speak, and write Latin, so no one objected very much if he spent part of his time catching fish in the Lake of Morat, where his home, the village of Motier, was located. The parsonage, besides having a view of the Bernese Alps, had a vineyard, an orchard, and a kitchen garden, these last being much to the point in a family that had to struggle to make ends meet. Louis kept his fish in a spring-fed pool in the garden, and they made a welcome addition to the family table. When he taught himself to dissect his catch, to mount and compare delicate bone structures, it seemed a harmless hobby. His mother thought perhaps Louis would be a doctor like her father and one of her brothers. Louis’ father thought that a doctor’s education would be beyond their means, however, and the youth was sent to a boarding school to learn bookkeeping.

Agassiz himself never made a secret of his plans. In fact, he was so openly aware of his own potentialities that, although most people took him at his own appraisal, there would always be those who considered him conceited. At about the age of fourteen he announced that he would one day head the greatest museum of his time—the Jardin des Plantes in Paris. Once literally a garden for the raising of medicinal herbs, the Jardin contained a menagerie, galleries of collections, a library, laboratories, and a lecture hall. Europe’s leading scientists, among them Baron Cuvier, founder of the science of comparative anatomy, and Baron Alexander von Humboldt, discoverer of the Humboldt Current off South America, lectured there. Agassiz’s father told him severely that he must prepare himself “for some humble walk in life” and not dream of such an exalted position. But Agassiz did more than dream: he went to the University of Zurich, then to Heidelberg, then to Munich, and finally to the Jardin des Plantes to study, where he became Cuvier’s protégé.

On Cuvier’s death, Agassiz was hired by the University of Neuchâtel in his native Switzerland at a salary of four hundred dollars a year. This princely sum enabled the young academician to marry Cécile Braun, sister of a student he had known at Heidelberg. He spent the next decade teaching and endeavoring to direct a printing and lithographing establishment which he had set up to produce his own immensely expensive monographs on European fresh-water and fossil fish. He won prizes and gradually gained a wide reputation. And during this period—almost overnight, it seemed—he became possessed by his idea that at one time the earth had been covered with ice. Baron von Humboldt, who had been his friend and patron at the Jardin des Plantes, reproached him bitterly for tossing aside his reputation as a scientist to propound so ridiculous a theory. But, after protracted argument, Humboldt came over to Agassiz’s side, as did other noted European scientists.

It was then, in 1846, that King Friedrich Wilhelm sent Agassiz to the New World. In triumph his students saw him off with a torchlight parade. But the opportunity came at a time of personal disaster. His wife, who was an artist, and whose fine drawings had enhanced his first Neuchâtel publications, had given up this work to care for their three children. Depressed because she could no longer help, harassed by lack of money and by the assistants who invaded her home as nonpaying guests, she left Agassiz to return to her family. The printing establishment failed and was sold at auction. When Agassiz accepted the King of Prussia’s offer, he was glad to get away. His popularity in the United States soon resulted in such high lecture fees that he was able to send money home to pay some of his debts and, as it were, to start life anew. Yet the smiling, genial face he presented to the world often hid a private sorrow.

Before his Lowell lectures began, Agassiz toured America’s scientific establishments. He visited Princeton, where Professor Joseph Henry’s department of physics was “remarkably rich in models of machinery and in electrical apparatus, to which the professor especially devotes himself.” Of course it was of still more interest to Agassiz as a natural scientist that “in the environs of the town” of Printeton he tried—and almost succeeded—in catching “a rare kind of turtle, remarkable for … the length of the tail.”

At Yale, Agassiz met Benjamin Silliman and decided he was “the patriarch of science in America.” He admired Yale’s fine collection of minerals, but again it was American wildlife that attracted him most. He had never before seen such great flocks of ducks as fluttered around the steamer after he left the train at New Haven and embarked upon Long Island Sound to complete his journey from Boston to New York. He returned to Boston to begin his lectures with his baggage augmented by a large barrel of fish he had collected in New York—at the Fulton Fish Market.

On his lecture platform, Agassiz usually set up his own portable blackboard, a roll of canvas painted black which pulled down like a window shade. He began his talks with descriptions of the most primitive sea creatures, now found in fossil form, and as he talked he drew in chalk to illustrate his words. Ernest Longfellow, son of the poet and himself an artist, said that Agassiz’s sketches had the beauty of the finest Japanese drawing. “It was a real treat,” he said, “to see a perfect fish or a skeleton develop under his hand with extraordinary sureness and perfect knowledge, without any hesitation or correcting.” The audience always breathed a sigh of regret when Agassiz erased his work. Of course, his pictures were not always pretty. To one young lady who inquired why a certain fish was so ugly, Agassiz replied: “Oh, God must have His leetle joke.”

The Swiss professor always began with “things easy to understand” and then would plunge into the more difficult, “where only technical language could be used.” The faces of the “thousands of people who sat and listened would take on an expression of struggling perplexity,” only to relax into comprehending smiles as the great professor made them understand.

Everyday-scenes acquired a new meaning for Agassiz’s audiences as they learned to identify rocky outcroppings and to look for signs of glacial action. Wherever Agassiz went, he found something to admire, giving his lecture-goers a new sense of local pride. It seemed a distinction that Princeton’s turtles should have extra-long tails. A huge rock in a farmer’s pasture near Manchester, Massachusetts, once merely a nuisance, became “Agassiz Boulder,” and strangers could be told how an ice floe brought it there. Agassiz’s discovery of ice-scored cliffs increased the popularity of the White Mountains as a resort, and today a height near Bethlehem, New Hampshire, is called “Mount Agassiz.”

By 1848, Agassiz, was a widely respected and beloved scientific figure, but he still held no permanent place in American education. In that year, Abbott Lawrence, who had just given fifty thousand dollars to Harvard to establish the Lawrence Scientific School, offered Agassiz. the chair of zoology and geology, with a salary of fifteen hundred dollars a year to be paid by Lawrence personally for a term of three years. To a man who had considered four hundred a year adequate, the sum was magnificent. Agassiz accepted the offer and became Harvard’s first foreign-born professor.

Cambridge now found itself containing a “permanent fixture” whose personality, as well as his whole approach to education, was startlingly different from anything the town had yet encountered. At Harvard, the Boston Transcript reported, Agassiz “smashed all the traditions of correctness of demeanor and chilly aloofness ... He wore a soft hat and smoked like a steam engine.” His gait was often referred to as a “trot” as he crossed the Harvard Yard puffing his huge cigar. “He smoked in classroom and sent out scientific knowledge through smoke rings.”

Maturity of attitude was Agassiz’s first demand of his students. There were no entrance examinations at the Lawrence Scientific School. A prospective student came by to see Professor Agassiz, had a talk with him, and was told that he was free either to stay or to go. Thus, Edward Sylvester Morse, a truculent youth who had been expelled from all the schools he had attended, became a student of Agassiz’s because of his extraordinary knowledge of land snails and the gleam in his eye when shells were mentioned. Morse became a famous conchologist, a professor at the Imperial University of Tokyo, and later director of the Peabody Museum in Salem, Massachusetts.

The enthusiastic teacher, realizing the limitations of nineteenth-century scholarship, never failed to caution his students that the books they read were not necessarily accurate. He put observation first, as always. Nathaniel Southgate Shaler, an early Lawrence student who was to become a professor of geology at Harvard, said Agassiz was the worst instructor but the best educator he had ever known. This would have pleased Agassiz, for it made just the point he was trying to explain to the president and fellows of Harvard: a university should be for men, not boys. Students should arrive well-instructed in the fundamentals so that they could take advantage of an opportunity for education.

It was a rule at Harvard that professors live in Cambridge, and Agassiz rented a house on Oxford Street just north of Harvard Yard. He established a startling household. Former associates from Europe, most of them penniless refugees, flocked to Oxford Street. Many were competent scientists, and Agassiz was able to find positions for them. Others were mere hangers-on who had heard that Agassiz was well paid in America and remembered his openhanded generosity. Sometimes Agassiz found himself with more than twenty nonpaying guests.

Along with the human assemblage, the house sheltered innumerable animal inmates. Everywhere he went, Agassiz continued to urge naturalists and laymen alike to send him specimens, live ones if possible. From Walden Pond, Henry David Thoreau sent fish, turtles, and a black snake. When Agassiz informed him joyfully that among the fish was an unnamed species, Thoreau was enchanted: “How wild it makes the pond and the township,” he wrote in his journal, “to find a new fish in it!” In a corner of Agassiz’s back yard was an eagle with clipped wings, and in a tank there were alligators. In his basement lived a bear who once got loose, managed somehow to open a keg of good German beer stored there, and then lurched up the cellar stairs—into the midst of one of Agassiz’s Sunday night supper parties. Scattering students, visiting scientists, and Harvard professors right and left, the tipsy bear climbed up on the table and helped himself to dinner.

In 1848, scarcely two years after Agassiz’s arrival in the United States, his wife, still in Switzerland, had died of tuberculosis. Agassiz sent for his son, but his two little girls remained for a time with relatives in Switzerland because his strange Cambridge household was not the place for them. With the thirteen-year-old Alex now added, however, Agassiz began to feel the need for some womanly assistance in managing his domestic affairs. It was Longfellow, who always took a great interest in his friends’ romances, who learned some news from the French wife of one of Agassiz’s scientist friends.

“It is true,” said the lady, “that he plans to marry. He has need of a housekeeper.” Nevertheless, it was a love match and not a marriage of convenience when, at King’s Chapel in Boston on April 25, 1850, Louis Agassiz married Elizabeth Cabot Cary, daughter of one of Boston’s leading bankers. “Lizzie looked lovely,” her sister wrote in her journal, “dressed in a green silk, white camel’s hair shawl, straw bonnet trimmed with white, and leathers on each side. After the ceremony they drove directly out of town”—to Agassiz’s home in “dusty Oxford Street.”

Elizabeth Agassiz received an early initiation in the sort of life that lay before her. Writing to her mother, she humorously issued a warning “to any woman who thinks of becoming the wife of a naturalist.’ One Sunday evening, she wrote, as she was dressing for church, “I ran to my shoe cupboard for my boots, and was just going to put my hands upon them when I caught sight of the tail of a good-sized snake, which was squirming about among the shoes. I screamed in horror to Agassiz, who was still sound asleep, that there was a serpent in my shoe-closet. ‘Oh, yes,’ said he sleepily, ‘I brought in several in my handkerchief last night.... I wonder where the others are.’” When all the snakes were finally rounded up, Agassiz “had the audacity” to call upon his wife to “admire their beauty.”

The deep attachment that Agassiz felt for his new home was clearly demonstrated when, in 1858, the directorship of the Jardin des Plantes and a seat in the French Senate were offered him. Here was the fulfillment of Agassiz’s boyhood ambition, but he declined the offer. The Jardin des Plantes now seemed to him a trifling affair compared to the vast museum he himself planned to build and direct, with laboratories, collections, lecture halls, and public exhibition rooms. His museum was to be “a library of the works of God,” Agassiz said, and he planned to build it in Cambridge, Massachusetts.

To realize such a vision, Agassiz would need money, but, always a successful solicitor of funds for scientific projects, he would not miss the patronage of a Bonaparte or a Friedrich Wilhelm. In America he found Francis Calley Gray of Boston, descendant of a pioneer maker of shoes in Lynn. Impressed by Agassiz, Gray left fifty thousand dollars in his will to establish a museum of natural history connected with Harvard. But Mr. Gray earmarked his money expressly for the purchase of collections, prohibiting its expenditure for brick and mortar. Agassiz now went to the Massachusetts legislature and, contrary to the expectations of his friends and advisers, got an appropriation of one hundred thousand dollars. Over seventy thousand dollars more was raised by public subscription for construction, and the first section of what would eventually become a formidable row of tall brick buildings on Oxford Street could now be started. The name decided upon was “Museum of Comparative Zoology,” because Agassiz believed that the study of natural history transcended in importance the name of any one man. But the museum was soon familiarly known as “the Agassiz.” It still is. A later acquisition of curious examples of German glass-blowing gave the museum its present reputation as “the place where the glass flowers are.”

Agassiz found another sponsor for natural history while the Civil War was still in progress. Nathaniel Thayer, partner in the firm eventually to become Kidder, Peabody, and possessor of one of the largest fortunes acquired by any New Englander, financed Agassiz᾿s Thayer Expedition to Brazil. It realized another early dream. Ever since his Munich days, when he had described in Latin the Brazilian fish brought back by two scientists, Spix and Martius, he had longed to go to Brazil himself to find more and rarer specimens. In 1865 he was on his way.

Mrs. Agassiz went along, the only woman in the party. What had at first been planned as a vacation for Agassiz developed into a full-scale operation, with paid assistants and student volunteers. Among the volunteers was Stephen van Rensselaer Thayer, son of Agassiz’s patron, and Walter Hunnewell, blessed with a large income and an amiable disposition. Hunnewell brought along a camera and worked hard at learning the use of this remarkable contraption. Among the other students accepted was William James, future Harvard professor of psychology.

The Colorado, with Agassiz and his party on board, sailed from New York on March 30. Agassiz’s stateroom looked like “a huge Christmas stocking into which enthusiastic Santa Clausi (or æ) were perpetually thrusting wines, cigars, oranges, apples, chocolate drops and books and newspapers,” said Sam Ward, Julia Ward Howe’s genial brother, who had come to see the party off. Agassiz was “flying around … now drawing a check, now giving an order” and distributing handshakes “as freely as Louis Philippe on his accession.” He had been up all night, but when someone suggested he go to bed as soon as the ship cleared the Narrows, Agassiz scoffed at the idea. He must at once begin charting the temperature of the sea water “for our approach to the Gulf Stream,” he said.

Agassiz gave a lecture to his assistants every day aboard ship. It was a “ long lecture,” remarked William James, but Mrs. Agassiz took note of the fact that “all the passengers, several officers of the ship and the Captain” came. With the optimism that never left him, Agassiz planned the exploration, “explaining over the map of South America and making projects as if he had Sherman’s Army at his disposal,” James said.

The expedition reached the bay of Rio de Janeiro on April 23. Agassiz immediately exerted his charm upon Dom Pedro II, Emperor of Brazil, with the result that the Amazon, not yet officially open to commerce, was opened to Agassiz, with the Emperor furnishing guides and arranging free transportation. Off went the Thayer Expedition, north along the coast, then up the Amazon in the steamer Incamiaba. The deck provided the “pleasantest sleeping place,” and here the whole party slung their hammocks, Mrs. Agassiz’s being rose-colored with white gauze curtains. “Can this be really Lizzie Cary, floating up the Amazon with a parcel of naturalists?” she wondered. Or would she wake “and find it all a dream?”

There was nothing dreamlike about the way Agassiz worked. The Amazon was teeming with fish, none of them safe from his nets. He discovered many new species, among them one that carried its young in its mouth; this he named for the Emperor, a touching tribute. Agassiz also wanted botanical specimens, and bird skins, and living animals such as a sloth, assorted monkeys, and some turtles. He was especially interested in the natives, but as there seemed no practical way of bringing any home, he set Hunnewell to photographing them.

Some of Agassiz’s happiest days were spent on a plantation on a lake inland from the Amazon. His artist was kept frantically busy recording the colors of lake fish new to science, while Agassiz jotted down observations and plopped hundreds of specimens into preserving alcohol. Here, after watching native dances one evening, Mrs. Agassiz was asked by the Indians to demonstrate a dance of her own people. She and “Ren” Thayer waltzed, to illustrate the folkways of Boston.

Agassiz found what he thought were glacial remains in Brazil, and would have liked to look for more in the Andes; so he was disappointed in not being able to visit Peru and Uruguay. In July, 1866, the Thayer Expedition, stocked with more than eighty thousand specimens for the museum, had to return home.

Five years later, however, on a gray December afternoon in 1871, with “the first snow-storm of the New England winter” just beginning, Agassiz and his wife set out again. This time, they would explore a glacier in the Strait of Magellan, easily seen from the main channel of the strait. It had been mentioned often in the accounts of travelers, but no one had ever recorded approaching it. “A wall of ice” stretched the whole width of the valley, and Agassiz declared that this was “one of the greatest glaciers he had ever seen.” Along its lower edge, where a rushing river began its course, were “deep caves of blue, transparent ice” and on going inside one, they saw “between the lower surface of the ice and the ground the accumulated mass of stones, pebbles, and boulders” called ground moraine. That night they “dined gayly,” pledging the glacier in a glass of champagne and naming it, by right of exploration, the Hassler—in honor of their Geodetic Survey steamer.

During the Civil War, Agassiz became a naturalized American citizen. “I seem like the spoiled child of the country,” he said, and he wanted to do something in return for all the happiness he had found here. When he had arrived in 1846, natural history museums were almost nonexistent. There were collections of curios here and there—skulls in Philadelphia, shells in Maine. By 1872, when he came back from the Hassler expedition, there were good museums in almost every American city, most of them Agassiz-inspired, many of them with Agassiz-trained curators. But Louis Agassiz could never feel that his debt to the United States was paid, and he plunged into a new project, a summer school for the teaching of marine natural history—the forerunner of the Marine Biological Laboratory at Woods Hole, Massachusetts.

Once more a sponsor came forward as soon as Agassiz proposed his plan. This time it was John Anderson, a New York merchant, who gave his island of Penikese in Buzzard’s Bay off New Bedford, together with fifty thousand dollars, to start the project. The Anderson School of Natural History opened in July, 1873, with about fifty students, many of them women. Considerable publicity resulted from the startling sight of “ladies dissecting fish.” Agassiz’s charm as a lecturer was undiminished, and workmen, in the midst of remodeling some buildings, would put down their tools to listen to him. It was perhaps a still greater tribute when the carpenters agreed to work overtime to finish the lecture hall. Most of the students gathered at Penikese during the summer were teachers, and this was perhaps the most sympathetic group Agassiz ever had. It was to be his last experience as a leader in the ever-expanding field of natural science, and it was perhaps his happiest one.

Agassiz always worked at high tension and he had had several warnings of ill health, the most serious being a cerebral hemorrhage which temporarily impaired his speech and kept him in bed for many months. That was in 1869, and he had recovered. But one day in December, 1873, he went to his laboratory feeling “strangely asleep.” He returned home earlier than usual and lay down on the couch in his study. Soon losing consciousness, he died December 14, at the age of sixty-six.

“Men who have made their mark in the history of science, disappear from the history of the very center where they have been most active.” So said Agassiz’s son, himself a scientist of high repute. But it was Louis Agassiz, the man, whom people remembered. The poets who knew him—Longfellow, Whittier, Emerson, and Lowell—all tried to express what this warm-hearted human being had meant to them. Longfellow remembered him “in life’s rich noon-tide, joyous, debonaire.” To Whittier he was always “hopeful, trustful, full of cheer.” James Russell Lowell memorialized Agassiz in more than five hundred lines, but came closest to catching the essence of the man in eleven words:

“His magic was not far to seek,—/ He was so human!”

We hope you enjoy our work.

Please support this magazine of trusted historical writing, now in its 75th year, and the volunteers that sustain it with a donation to American Heritage.