Humboldt's Cosmos Read online

  HUMBOLDT harbored great hopes for this expedition to the New World. It was a daring, some would say vain, notion, but it was one that had been in his mind for years, long before his arrival in Paris. On the eve of his departure from the Spanish port of La Coruna, Humboldt sat in his cabin aboard the frigate Pizarro and spelled out his hopes for the journey: “In a few hours we sail round Cape Finisterre. I shall collect plants and fossils and make astronomic observations. But that’s not the main purpose of my expedition—I shall try to find out how the forces of nature interact upon one another and how the geographic environment influences plant and animal life. In other words, I must find out about the unity of nature.”

  For Humboldt, “the unity of nature” meant the interrelation of all the physical sciences—such as the conjunction between biology, meteorology, and geology that determined where specific plants grew—which the scientist unraveled by discovering patterns in myriad, painstakingly collected data. This ambition to view nature as a whole wasn’t unique to Humboldt, though. It was a quest that historians believe had begun with the ancient Greek philosopher Thales of Miletus, in the sixth century B.C. Recognized as the founder of Greek geometry, Thales also taught that all matter is ultimately composed of water. Though dead wrong, the theory was still an intellectual turning point, since it marked the first time anyone had tried to explain natural phenomena without appeal to religious dogma. It was also the first time that anyone had tried to explain the whole, divergent physical world in one grand unifying principle. Thales, now recognized as the first natural philosopher, had tried to penetrate the obvious differences in things—between a rock and a person, say—and to see the not-so-obvious similarities.

  Two hundred years later, Aristotle had been the first to use extensive observation to try to tease the truth from the natural world. But the next great contribution along these lines had come nearly two millennia later, from Francis Bacon. Lord chancellor under James I as well as a philosopher, Bacon had defined the scientific method, thereby laying the conceptual groundwork of modern science. And science, in E. O. Wilson’s phrase, “was the engine of the Enlightenment,” that great eighteenth-century movement to replace dogma and tradition with reason and observation and to supplant tyranny and slavery with humanism and social progress. It had been during these rousing years that René Descartes had suggested that all knowledge could be expressed mathematically. And it hadn’t been long afterward that Isaac Newton had used a few simple formulas to explain the functioning of much of the physical world. Newton’s achievement had been a masterstroke of unification that would change the world forever.

  However, despite its transcendent successes, by the beginning of the nineteenth century, faith in the old paradigm was fading. A new worldview was rising in rebellion against the cool rationalism of the Enlightenment, suggesting that there is a higher truth that man can know, not through reason, but only through the emotions—the worldview of Romanticism. The approach to science in Germany had always been less mechanistic, more spiritual, and more speculative than in England and France, and by the late eighteenth century a school of thought had arisen there called Naturphilosophie. More influential in biology than in the physical sciences, the nature philosophers suggested that every animate and inanimate object was infused with the eternal World Spirit, the driving force behind the development of the universe. The school’s principal advocate was Johann Wolfgang von Goethe, who in addition to being one of the great poets of all time, was also an avid naturalist, and its leading philosopher was Friedrich Schelling, who suggested that there existed an underlying unity of all things that man could never discern through logic alone.

  This was the world in which Humboldt had come of age; in the waning days of the Enlightenment and the dawn of Romanticism, and along with figures such as Goethe, he formed a bridge between the rational and intuitive modes of understanding the universe. In his belief in rigorous quantification, Humboldt was a child of the Enlightenment. All too often, he believed, the nature philosophers (among whom he had once counted himself) spun imprecise observations and half-baked generalities into elaborate “scientific” theories that threatened to topple at the slightest nudge of logic. Instead, he envisioned a more stringent methodology in which painstaking observations were cemented, brick by scrupulous brick, into an enduring foundation.

  Toward this end, Humboldt gathered perhaps the most sophisticated armamentarium of scientific instruments ever before assembled. Each of the forty-two instruments, nestled in its own velvet-lined box, was the most accurate and most portable of its kind yet devised. There were thermometers for measuring the temperature of air and water, barometers for fixing elevation above sea level, quadrants and sextants for determining geographic position (including a sextant small enough to fit in a pocket), telescopes, microscopes, a balance scale, chronometers, compasses, a rain gauge, substances for performing chemical assays, electric batteries, electrometers (for measuring electric current), a Leyden jar (a glass vessel capable of storing static electricity), theodolites (surveyors’ instruments for measuring vertical and horizontal angles), hygrometers (for measuring atmospheric moisture), a dip needle (for measuring variations in the orientation of the earth’s magnetic field), and eudiometers (for measuring the amount of oxygen in the air). Everything would be measured, using the finest instruments and most sophisticated techniques available, for such data were the basis of all scientific understanding. This exacting methodology, in fact, would become known as “Humboldtian science.”

  But despite his unyielding empiricism, Humboldt was also touched by the new Romantic spirit of the age. He was not content simply to measure and catalog nature. Combining meticulous observation with inspired description, scientific rigor with almost childlike wonder, he had an abiding passion for the transcendental beauty around him. Grandeur and marvel are words he used often to describe natural phenomena. For what was scientific understanding without aesthetic appreciation? What was the good of knowing that the earth’s atmosphere was seventy-eight percent nitrogen, if one couldn’t be moved by the beauty of a cloudless summer sky? What was the use of measuring the acceleration of falling water if one couldn’t be awed by a raging cataract? Even Humboldt’s countryman Immanuel Kant, the leading philosopher of the Enlightenment, had argued that reason alone, because it was limited by input from the senses, could never yield a complete understanding of reality. Aesthetic appreciation must complement pure reason, if one were ever to grasp the true nature of the world.

  “Nature herself is sublimely eloquent,” Humboldt wrote. “The stars as they sparkle in the firmament fill us with delight and ecstasy, and yet they all move in orbit marked out with mathematical precision.” To truly understand nature, one must feel the ecstasy as well as grasp the mathematics.

  Kant’s ideas influenced Humboldt in other ways as well. In his lectures on physical geography, Kant had taken the great Swedish naturalist Carl Linnaeus to task for his narrow, categorizing view of botany. Instead of trying to pigeonhole the natural world into prescribed classifications, Kant had argued, scientists should work to discover the underlying scientific principles at work, since only those general tenets could fully explain the myriad natural phenomena. Thus Kant had extended the unifying tradition of Thales, Newton, Descartes, et al. But besides arguing for the unity of knowledge, Descartes had also introduced the idea of reductionism—dividing the world into smaller units that can be studied separately—which has fueled the phenomenal growth of Western science in the centuries since. Humboldt agreed with Kant that a different approach to science was needed, one that could account for the harmony of nature that lay beneath the apparent diversity of the physical world. The scientific community, despite its prodigious discoveries, seemed to have forgotten the Greek vision of nature as an integrated whole. Content to collect and label rocks, they never thought to ask how those specimens were related to the surrounding types of soil, or what influence they exerted on the local flora. “Rather than discover new, isolated
facts I preferred linking already known ones together,” Humboldt later wrote. Science could only advance “by bringing together all the phenomena and creations which the earth has to offer. In this great sequence of cause and effect, nothing can be considered in isolation.” It was in this underlying connectedness that the genuine mysteries of nature would be found.

  This was this deeper truth that Humboldt planned to lay bare—a new paradigm from a New World. For only through travel, despite its accompanying risks, could a naturalist make the diverse observations necessary to advance science beyond dogma and conjecture. Although nature operated as a cohesive system, the world was also organized into distinct regions whose unique character was the result of all the interlocking forces at work in that particular place. To uncover the unity of nature, one must study the various regions of the world, comparing and contrasting the natural processes at work in each.

  The scientist, in other words, must become an explorer. And the New World, with its lofty mountains, volcanoes, and inexhaustible variety of plant life, offered “ample fields for the labors of the naturalist. On no other part of the globe is he called upon more powerfully by nature to raise himself to general ideas and the cause of phenomena and their mutual connection.” Humboldt planned to investigate Cuba, then to explore Spain’s vast holdings in North America. In the laboratory provided by the unspoiled New Continent, he hoped to discover how nature’s forces act upon one another and how the geographic environment works on animals and plants. It was toward this end that all his studies—of plants and minerals, physics and astronomy, history, art, mythology—his travels across Europe, even his experiments on human nerves and muscles, had been ineluctably building.

  And now, at last, he was embarked on a journey that would allow him to test these principles in the field. Aboard the Pizarro, Humboldt had the realization, at once heady and daunting, that the purpose of his life was about to be fulfilled.

  Assuming, that is, they could slip past the British blockade.

  Two: Tenerife

  THE ancient city of La Coruña, on the northwest tip of Spain, rested on a hammer-shaped peninsula in the Atlantic Ocean. From the battlements, one could take in the sweep of town and water below. Propped south of the hammer’s head, like a nail waiting to be pounded in, was a dot of an island holding the sixteenth-century fortress known as Castle San Antonio. A little more than a mile to the northwest, on the tip of the hammer’s claw, was the port’s other principal monument, the lighthouse called the Tower of Hercules, after La Coruña’s apocryphal founder. Ninety-two feet high, with square stone walls and an incongruous baroque roof, the tower had been rebuilt in the eighteenth century on a foundation laid by the Roman emperor Trajan some sixteen hundred years before. To the west sprawled La Pescadería, the fishermen’s quarter. And beyond that, on the hammer’s handle, stretched a long arc of waterfront enclosing the city’s raison d’être—the harbor.

  One of Spain’s most ancient seaports, La Coruña had been occupied by the Celts, Phoenicians, Romans, Moors, and Portuguese before the Spanish. It was from La Coruña that Prince Philip of Spain had set sail in 1544 for his wedding with Mary Tudor of England. It was also from here, in 1588, that the Spanish Armada had departed for Britain, bent on a less subtle brand of diplomacy. The following year, Francis Drake, whose name was still cursed in these parts, had sailed into the harbor and sacked the town in retribution for that ill-fated attack. More recently, the English had scored a naval victory against the French there in 1747. And it was from La Coruña, on June 5, 1799, that twenty-nine-year-old Alexander von Humboldt embarked on his monumental journey of discovery to Latin America.

  The Pizarro had been loaded and ready to sail for two days, but the weather had refused to cooperate. Then on the evening of June 4, the wind finally shifted to the northeast. By morning the fog was thick enough to obscure Castle San Antonio across the harbor, but the Pizarro’s Captain Cagigal consulted with the master of the Alcudia, a packet ship also delayed in port by the British blockade, and it was decided. The ships would sail that afternoon.

  The Pizarro nearly didn’t make it out of the harbor. Weighing anchor at two o’clock, the ship made eight short tacks in the confines of the port. But three of the maneuvers proved useless in the contrary wind, and the vessel stalled under the battlements. The crew and passengers watched with mounting terror as the current drove them helplessly toward shore. Only when it was practically on the rocks did the Pizarro finally gain some headway and sail out of danger. It was not an auspicious beginning to a long ocean voyage.

  Soon after, the ship passed under Castle San Antonio, and Humboldt couldn’t help thinking of the poor Marqués de Malaspina incarcerated there. Admiral Alessandro Malaspina had been the last man Spain had entrusted with making an exploration of their New World territory, a 1789 expedition in search of the Northwest Passage. Having failed in that mission, Malaspina had been arrested for his unconventional political beliefs and had spent the past decade imprisoned at La Coruña without benefit of trial. As he sailed by the castle where his most recent predecessor was being held, the lesson wasn’t lost on Humboldt. “On the point of leaving Europe to visit the countries which this illustrious traveler had visited with so much advantage,” he wrote, “I could have wished to have fixed my thoughts on some object less affecting.”

  By six-thirty the ship had rounded the point and passed the Tower of Hercules, whose weak coal fire barely penetrated the afternoon fog. As night deepened, the wind picked up and they began to make better speed, though the seas had risen as well. Leaving the harbor, they tacked to the northwest to skirt the British squadron that had been reported offshore—a necessary precaution because the Pizarro was a Spanish ship.

  Though Spain had originally allied herself with England and the other monarchies as France sought to export its revolution to the rest of Europe, it had made peace with Paris in 1795, along with Holland, Tuscany, and Humboldt’s own Prussia. Accordingly, if the Pizarro were captured, she would be conveyed to Spain’s neighbor and Britain’s ally, Portugal. Though Humboldt and the other civilian passengers would be released, they would lose their passage to the New World. After the myriad frustrations he and Bonpland had endured to get even this far, the thought of starting all over again was more than Humboldt could bear.

  Though he’d dreamed of this moment since childhood, the prospect of leaving Europe for the first time filled Humboldt with an unexpected solemnity. “Separated from the objects of our dearest affections, and entering in some sort on a new state of existence, we are forced to fall back on our own thoughts,” he wrote, “and we feel within ourselves a dreariness we have never known before.” At nine o’clock on that first evening out of port, the Pizarro passed the town of Sisarga. There was a light burning in a fishing hut there, and, knowing it was the last object they would see in Europe, Humboldt and Bonpland sat on deck and watched the lamp slip from sight. “So many memories are awoken in our imagination by a dot of light in a dark night, flickering above the rough waves, signaling our homeland!” Humboldt found.

  The next day, the Pizarro passed Cape Finisterre, southwest of La Coruña. On June 8, at sunset, they spied the English squadron scudding southeast along the coast and abruptly changed course. Named in honor of the Spanish conqueror of Peru, the Pizarro has been variously described as a corvette or a light frigate. The difference is semantic—corvettes and frigates were similar classes of fighting ship, with three square-rigged masts and with their guns carried on a single deck. The corvette was smaller and faster, with only twenty cannon or so, versus the thirty or forty that would be shipped on a full-size frigate.

  Whether a small frigate or a corvette, the Pizarro was built for speed more than for firepower. This made her an ideal vessel for the long passage to Spain’s New World colonies, but it meant that en route she would have to rely on her agility to evade enemy warships, especially England’s huge ships-of-the-line, which carried sixty to a hundred cannon stacked in three deadly tiers. In t
he interest of stealth, there would be no lamps permitted in the great cabin for the remainder of the voyage, standard procedure on Spanish ships at sea during those perilous times.

  Though he appreciated the need for such a precaution, the ever restless Humboldt despaired at all those dark, empty evenings without his books or his work. “In the torrid zone, where twilight lasts a few minutes, our operations ceased almost at six in the evening,” he complained. “This state of things was so much the more vexatious to me as from the nature of my constitution I never was subject to seasickness, and feel an extreme ardor for studying during the whole time I am at sea.”

  Humboldt and Bonpland’s days aboard the Pizarro quickly settled into a scientific routine. One can fairly see them standing on deck, hunched over their instruments and notebooks, while the crew scurries around them and the other passengers watch with frank curiosity or outright mistrust. Taking advantage of the calm seas between Madeira and the coast of Africa, the pair unpacked their dip needle. Rotating freely on its axis, the dip needle acted as a kind of vertical compass, measuring the orientation of the earth’s magnetic field. Humboldt and Bonpland also took water-temperature readings during this part of the voyage and confirmed Benjamin Franklin and Jonathan Williams’s counterintuitive observation that Atlantic waters are actually cooler over shoals than over deeper regions, due to the upwelling of cold water from the ocean floor.