On July 13, 1772, with the Resolution and the Endeavour, he set out again to find the imaginary southern continent. He searched the sea eastward and southward between the Cape of Good Hope and New Zealand, and crossed the Antarctic Circle to 71° south latitude without seeing land; then the mounting danger from ice floes compelled him to turn back. He visited Easter Island, and wrote a description of its gigantic statues. He charted the Marquesas and Tonga Islands, and called the latter “Friendly” because of the gentleness of the natives. He discovered New Caledonia, Norfolk Island, and the Isle of Pines (Kunie). He traversed the South Pacific eastward to Cape Horn, continued over the South Atlantic to the Cape of Good Hope, sailed north to England, and reached port July 25, 1775, after a voyage of over sixty thousand miles and 1,107 days.
His third expedition sought a water route from Alaska across North America to the Atlantic. He left Plymouth July 12, 1776, with the Resolution and the Discovery, sailed around the Cape of Good Hope, touched again at Tahiti, proceeded northeast, and chanced upon his greatest discovery, the Hawaiian Islands (February, 1778). These had been seen by the Spanish navigator Juan Gaetano in 1555, but they had been forgotten by Europe for over two centuries. After continuing northeast, Cook reached what is now the state of Oregon, and surveyed the North American coast up to and beyond Bering Strait to the northern limits of Alaska. At 70° 41’ north latitude his advance was barred by a wall of ice rising twelve feet above the sea and stretching as far as the crow’s-nest eye could reach. Defeated in his search for a Northeast Passage across America, Cook returned to Hawaii. There, where previously he had received a friendly welcome, he met his end. The natives were kind but thievish; they stole one of the Discovery’s boats; Cook led a group of his men to recapture it; they succeeded, but Cook, who insisted on being the last to leave the shore, was surrounded by the angry natives, and was beaten to death (February 14, 1779), aged fifty-one. England honors him as the greatest and noblest of her maritime explorers, an accomplished scientist, a fearless captain loved by all his crews.
Almost as heroic was the expedition led by Jean François de Galaup, Comte de La Pérouse, commissioned by the French government to follow up Cook’s discoveries. He sailed in 1785 around South America and up to Alaska, crossed to Asia, and was the first European to pass through the strait (which till lately bore his name) between Russian Sakhalin and Japanese Hokkaido. Turning south, he explored the coast of Australia and reached the Santa Cruz Islands. There, apparently, he was shipwrecked (1788), for he was never heard of again.
Land exploration was also a challenge to the lust for adventure and gain. In 1716 a Jesuit missionary reached Lhasa, the “Forbidden City” of Tibet. Carsten Niebuhr explored and described Arabia, Palestine, Syria, Asia Minor, and Persia (1761). James Bruce traveled through East Africa and rediscovered the source of the Blue Nile (1768). In North America French explorers founded New Orleans (1718) and moved north along the Mississippi to the Missouri; in Canada they struggled to reach the Pacific, but the Rocky Mountains proved insurmountable. Meanwhile English settlers pushed inland to the Ohio River, and Spanish friars led the way from Mexico through California to Monterey, and up the Colorado River basin into Utah; soon North America would be one of the prizes in the Seven Years’ War. In South America La Condamine, after measuring a degree of latitude at the equator, led an expedition from the sources of the Amazon near Quito to its mouth at the Atlantic, four thousand miles away.
The mapmakers could never quite keep up with the explorers. Through half a century (1744–93) César François Cassini and his son Jacques Dominique issued in 184 successive sheets a map of France thirty-six feet long by thirty-six feet wide, showing in unprecedented detail all roads, rivers, abbeys, farms, mills, even wayside crosses and gallows. Torbern Olof Bergman, not content with being one of the greatest chemists of the eighteenth century, published in 1766 a Werlds Beskribning, or world description, summarizing the meteorology, geology, and physical geography of his time. He suggested that many islands were peaks of mountain ranges now mostly submerged; so the West Indies might be the remains of a range that had connected Florida with South America. Horace de Saussure, after twenty-four years as professor of philosophy at the University of Geneva, made famous ascents of Mont Blanc (1787) and the Klein Matterhorn (1792), and composed voluminous studies of Swiss mountains in their atmospheric conditions, formations, strata, fossils, and plants, making a marvelous mixture of meteorology, geology, geography, and botany. Let us remember, when we are told that history is the Newgate Calendar of nations, that it is also the record of a thousand forms of heroism and nobility.
VII. BOTANY
1. Linnaeus
And so we come to life! Now that the compound microscope had been developed, it was possible to examine more minutely the structure of plants, even to the secrets of their sex. Botany graduated from its servitude to medicine, and Linnaeus mapped the teeming world of life with the care and devotion of a scientific saint.
His father, Nils Linné, was pastor of a Lutheran flock at Stenbrohult in Sweden. The son of a clergyman has especial difficulty in preserving his piety, but Carl managed it, and found, especially in the plant world, endless reasons for thankfulness to the Creator. And indeed there are moments when life appears so beautiful that only an ingrate could be an atheist.
Nils was an enthusiastic gardener, who loved to secure choice trees and rare flowers and set them in the soil around his rectory as a living litany of praise. These were Carl’s toys and intimates in boyhood, so that (he tells us) he grew up with “an unquenchable love for plants.”78 Many a day he played truant from school to collect specimens in woods and fields. The father longed to make him a clergyman, for the lad was the soul of goodness, and might teach more by deed than by creed; but Carl took to medicine as the only career in which he could both botanize and eat. So in 1727, aged twenty, he was enrolled as a medical student in the University of Lund. A year later, with glowing recommendations from his teachers, he was sent to the University of Uppsala. As one of five children he could not receive much financial aid from his parents. Too poor to have his shoes repaired, he put paper in them to cover the holes and keep out some of the cold. With such incentives to study, he advanced rapidly in both botany and medicine. In 1731 he was appointed deputy lecturer in botany, and tutor in the home of Professor Rudbeck, who had twenty-four children; “now, through the grace of God,” he wrote, “I have an income.”79
When the Vetenskapssocietet (Scientific Society) of Uppsala decided to send an expedition to study the flora of Lapland, Linnaeus was chosen as leader. He and his young associates set out on May 12, 1732. He described the departure in his naturally flowery style:
The sky was bright and genial; a gentle breeze from the west lent a refreshing coolness to the air.… The buds of the birch trees were beginning to burst into leaf; the foliage on most trees was fairly advanced; only the elm and the ash remained bare. The lark was singing far on high. After a mile or so we came to the entrance of a forest; there the lark left us, but on the crest of the pine the blackbird poured forth his song of love.80
This is typical of Linnaeus; he was ever alert, with every sense, to the sights, sounds, and fragrances of nature, and never admitted any distinction between botany and poetry. He led his troop over 1,440 miles of Lapland, through a hundred dangers and hardships, and brought them back safely to Uppsala on September 10.
Still almost penniless, he tried to support himself by lecturing, but a rival had the lectures prohibited on the ground that Linnaeus had not yet completed the medical course or taken his degree. Meanwhile Carl had fallen in love with “Lisa”—Sarah Elisabeth Moraea, daughter of a local physician. She offered him her savings, he added his own, and, so financed, he set out for Holland (1735). At the University of Harderwijk he passed his examinations and received his medical degree. A year later, at Leiden, he met the great Boerhaave, and almost forgot Lisa. Inspired and helped by that nobleman of science, Linnaeus issued one of the classi
cs of botany, Systema Naturae. It ran through twelve editions in his lifetime; in the first it consisted of only fourteen folio sheets; in the twelfth it ran to 2,300 pages, in three volumes octavo. Near Amsterdam he replenished his funds by reorganizing and cataloguing the botanical collection of George Cliffort, a director of the East India Company. With incredible industry he brought out in 1736 Bibilotheca botanica, and in 1737 Genera Plantarum. In 1738 he went to Paris to study the Jardin du Roi. There, without introducing himself, he joined a group of students to whom Bernard de Jussieu was lecturing in Latin on exotic plants. One plant puzzled the professor; Linnaeus ventured to suggest, “Haec planta faciem americanam habet” (This plant has an American appearance). Jussieu looked at him, and surmised, “You are Linnaeus.” Carl confessed, and Jussieu, with the fine brotherhood of science, gave him an unstinted welcome.81 Linnaeus was offered professorships in Paris, Leiden, and Göttingen, but he thought it time to return to Lisa (1739). Such long betrothals were not then unusual, and in many cases they probably contributed to stability of morals and maturity of character. They married, and Carl settled down as a physician in Stockholm.
For a time, like any young doctor, he waited in vain for patients. One day in a tavern he heard a youth complain that no one had been able to cure him of gonorrhea. Linnaeus cured him, and soon other young men who had been too anxious to prove their manhood came for similar relief. The doctor’s practice spread to lung ailments. Count Carl Gustav Tessin, speaker of the House of Nobles in the Riksdag, became acquainted with him, and secured him appointment as physician to the Admiralty (1739). In that year Linnaeus helped to found the Royal Academy of Science, and became its first president. In the fall of 1741 he was chosen professor of anatomy at Uppsala; soon he exchanged this chair for that of botany, materia medica, and “natural history” (geology and biology); at last he was the right man in the right place. He communicated his enthusiasm for botany to his students; he worked with them in informal intimacy, and he was never so happy as when he led them on some natural-history foray.
We made frequent excursions in search of plants, insects, and birds. On Wednesday and Saturday of each week we herborized from dawn till dark. Then the pupils returned to town wearing flowers in their hats, and escorted their professor to his garden, preceded by rustic musicians. That was the last degree of magnificence in our pleasant science.82
He sent some of his students to various quarters of the world to secure exotic plants; for these young explorers (some of whom sacrificed their lives in their quest) he secured free passage on the ships of the Dutch East India Company. He stimulated them with the hope of adding their names to plants in the great system of nomenclature that he was preparing. They noted that he gave the name camellia to the flowering shrub that had been found in the Philippines by the Jesuit George Kamel.
In the Systema naturae, the Genera Plantarum, the Classes Plantarum (1738), the Philosophia botanica (1751), and the Species Plantarum (1753) he built up his monumental classification. In this task he had several predecessors, especially Bauhin and Tournefort; and Rivinus had already (1690) suggested a binomial method of naming plants. Despite these labors Linnaeus found the collections of his time in a state of disorder that seriously hampered the scientific study of plants. Hundreds of new varieties had been discovered, to which botanists had given conflicting names. Linnaeus undertook to classify all known plants first by their class, then in the class by their order, in the order by their genus, in the genus by their species; so he arrived at a Latin name internationally acceptable. As the basis of his classification he took the presence and character, or the absence, of distinctively reproductive organs; so he divided plants into “phanerogams,” those having visible organs of reproduction (their flowers), and “cryptogams,” in which (as in mosses and ferns) there are no flowers producing seeds, and the reproductive structures are hidden or inconspicuous.
Some timid souls objected that this emphasis on sex would dangerously influence the imagination of youth.83 Hardier critics, in the course of the next hundred years, pointed out more basic defects in Linnaeus’ classification. He was so interested in finding nooks and names for plants that for a time he diverted botany from the study of plant functions and forms. Since a transformation of species would have confused his system, and would have contradicted the Book of Genesis, he laid down the principle that all species had been directly created by God and had remained unchanged throughout their history. Later (1762) he modified this orthodox attitude by suggesting that new species might arise by the hybrid crossing of kindred types.84 Though he treated man (whom he trustfully called “homo sapiens”) as part of the animal kingdom, and classified him as a species in the order of primates, along with the ape, his system impeded the development of evolutionary ideas.
Buffon criticized the Linnaean classification on the ground that genera and species are not objective things but are merely names for convenient mental divisions of a complex reality in which all classes, at their edges, melt into one another; nothing exists, outside the mind, except individuals; here was the old medieval debate between realism and nominalism. Linnaeus (proving himself human) replied that Buffon’s eloquence must not be allowed to deceive the world; and he refused to eat in a room where Buffon’s portrait was hung along with his own.85 In a more genial moment he admitted that his arrangement was imperfect, that classification of plants by sexual apparatus left many loose ends; and in Philosophia botanica he proposed a “natural” system based upon the form and development of the organs of a plant. His nomenclature, as distinct from his classification, proved to be a great convenience, both in botany and in zoology, and with some modifications it still prevails.
In his old age Linnaeus was honored by all Europe as the prince of botanists. In 1761 he was knighted by the King, and became Carl von Linné. Ten years later he received a love letter from the second most famous author of the century, Jean Jacques Rousseau, who had translated the Philosophia botanica, and had found in botanizing a cure for philosophy: “Accept, kind sir, the homage of a very ignorant but very zealous disciple of yours, who owes in great part to meditation on your writings the tranquillity he enjoys… I honor you, and I love you with all my heart.”86
Linnaeus, like Rousseau and Voltaire, died in 1778. His library and botanical collections were bought from his widow by James Edward Smith, who joined others (1788) in founding the Linnaean Society of London to care for the “Linnaean treasure.” From that center a long series of publications spread the work of the botanist throughout Europe and America. Goethe named, as the greatest influences in his mental life, Shakespeare, Spinoza, and Linnaeus.87
2. In the Vineyard
Hundreds of devotees carried on the botanic quest. In France we find one of those virile families where a common dedication unites the members across the centuries. Antoine de Jussieu, coming up to Paris from Lyons, rose in 1708 to be director of the Jardin du Roi. His younger brother Bernard was a lecturer and “demonstrator” there; we have seen him welcoming Linnaeus. Another brother, Joseph, went to South America with La Condamine, and sent the Heliotropium peruvianum for transplantation in Europe. A nephew, Antoine Laurent de Jussieu, published in 1789 the work that began to replace the Linnaean system: Genera plantarum secundum ordines naturales disposita. He classified plants morphologically (according to their forms) by the presence, absence, or number of cotyledons (seed leaves): those plants that had none he called acotyledons; those with one only, monocotyledons; those with two, dicotyledons. His son Adrien carried on their work into the nineteenth century. In 1824 Augustin de Candolle, building upon the labors of the Jussieus, outlined the classification that is received today.
The sexuality of plants had been discovered by Nehemiah Grew in or before 1682, and had been confirmed by Camerarius in 1691. Cotton Mather reported from Boston to the Royal Society of London (1716) a demonstration of hybridization by wind pollination:
My neighbor planted a row of hills in his field with our Indian corn, but
such a grain as was colored red and blue; the rest of the field he planted with corn of the most usual color, which is yellow. To the most windward side this row infected four of the next neighboring rows, … to render them colored like what grew on itself. But on the leeward side no less than seven or eight rows were so colored, and some smaller impression was made on those that were yet further distant.88
In 1717 Richard Bradley proved the necessity of fertilization by an experiment with tulips. From twelve of these, “in perfect health,” he removed all pollen; “these bore no seed all that summer, while … every one of four hundred plants which I had let alone produced seed.”89 He studied cross-fertilization, and foresaw some fascinating results. “By this knowledge we may alter the property and taste of any fruit by impregnating the one with the farina [pollen] of another of the same class” but of a different variety or species. Moreover, “a curious person may by this knowledge produce such rare kinds of plants as have not yet been heard of”; and he told how Thomas Fairchild had grown a new variety “from the seed of a carnation that had been impregnated by the farina of the sweet William.” He found such interspecies hybrids to be sterile, and compared them with mules.