Seeking a foreign expedition With the financial resources to fund his scientific travels, he sought a ship on a major expedition. In the meantime, he went to Paris, where his brother Wilhelm was living. Paris was a great center of scientific learning and his brother and sister-in-law Caroline were well connected in those circles.
Louis-Antoine de Bougainville urged Humboldt to accompany him on a major expedition, likely to last five years, but the French revolutionary
Directoire placed
Nicolas Baudin at the head of it rather than the aging scientific traveler. On the postponement of Captain Baudin's proposed voyage of
circumnavigation due to continuing warfare in Europe, which Humboldt had been officially invited to accompany, Humboldt was deeply disappointed. He had already selected scientific instruments for his voyage. He did, however, have a stroke of luck with meeting
Aimé Bonpland, the botanist and physician for the voyage. Discouraged, the two left Paris for
Marseille, where they hoped to join
Napoleon Bonaparte in Egypt, but North Africans were in revolt against the French invasion in Egypt and French authorities refused permission to travel. Humboldt and Bonpland eventually found their way to
Madrid, where their luck changed spectacularly.
Spanish royal authorization, 1799 In Madrid, Humboldt sought authorization to travel to Spain's realms in the Americas; he was aided in obtaining it by the German representative of Saxony at the royal Bourbon court. Baron Forell had an interest in mineralogy and science endeavors and was inclined to help Humboldt. At that time, the
Bourbon Reforms sought to reform administration of the realms and revitalize their economies. At the same time, the
Spanish Enlightenment was in florescence. For Humboldt "the confluent effect of the Bourbon revolution in government and the Spanish Enlightenment had created ideal conditions for his venture". The Bourbon monarchy had already authorized and funded expeditions, with the
Botanical Expedition to the Viceroyalty of Peru to Chile and Peru (1777–88), New Granada (1783–1816), New Spain (Mexico) (1787–1803), and the
Malaspina Expedition (1789–94). These were lengthy, state-sponsored enterprises to gather information about plants and animals from the Spanish realms, assess economic possibilities, and provide plants and seeds for the Royal Botanical Garden in Madrid (founded 1755). These expeditions took naturalists and artists, who created visual images as well as careful written observations as well as collecting seeds and plants themselves. Crown officials as early as 1779 issued and systematically distributed
Instructions concerning the most secure and economic means to transport live plants by land and sea from the most distant countries, with illustrations, including one for the crates to transport seeds and plants. When Humboldt requested authorization from the crown to travel to Spanish America, most importantly, with his own financing, it was given positive response. Spain under the Habsburg monarchy had guarded its realms against foreigner travelers and intruders. The Bourbon monarch was open to Humboldt's proposal. Spanish Foreign Minister Don
Mariano Luis de Urquijo received the formal proposal and Humboldt was presented to the monarch in March 1799. Humboldt was granted access to crown officials and written documentation on Spain's empire. With Humboldt's experience working for the absolutist Prussian monarchy as a government mining official, Humboldt had both the academic training and experience of working well within a bureaucratic structure. , 1806 Before leaving Madrid in 1799, Humboldt and Bonpland visited the
Natural History Museum, which held results of
Martín Sessé y Lacasta and
José Mariano Mociño's botanical expedition to
New Spain. Humboldt and Bonpland met
Hipólito Ruiz López and
José Antonio Pavón y Jiménez of the royal expedition to Peru and Chile in person in Madrid and examined their botanical collections.
Venezuela, 1799–1800 were in the Amazon rainforest by the
Casiquiare River. Oil painting by
Eduard Ender, 1856. Humboldt did not like the painting as the instruments depicted were inaccurate. based on Humboldt's 1799 observations Armed with authorization from the King of Spain, Humboldt and Bonpland made haste to sail, taking the ship
Pizarro from
La Coruña, on 5 June 1799. The ship stopped six days on the island of
Tenerife, where Humboldt climbed the volcano
Teide, and then sailed on to the New World, landing at
Cumaná,
Venezuela, on 16 July. The ship's destination was not originally Cumaná, but an outbreak of typhoid on board meant that the captain changed course from
Havana to land in northern South America. Humboldt had not mapped out a specific plan of exploration, so that the change did not upend a fixed itinerary. He later wrote that the diversion to Venezuela made possible his explorations along the Orinoco River to the border of Portuguese Brazil. With the diversion, the
Pizarro encountered two large dugout canoes each carrying 18 Guayaqui Indians. The
Pizarros captain accepted the offer of one of them to serve as pilot. Humboldt hired this Indian, named Carlos del Pino, as a guide. Venezuela from the 16th to the 18th centuries was a relative backwater compared to the seats of the Spanish viceroyalties based in New Spain (Mexico) and Peru, but during the Bourbon reforms, the northern portion of Spanish South America was reorganized administratively, with the 1777 establishment of a captaincy-general based at Caracas. A great deal of information on the new jurisdiction had already been compiled by François de Pons, but was not published until 1806. Rather than describe the administrative center of Caracas, Humboldt started his researches with the valley of Aragua, where export crops of sugar, coffee, cacao, and cotton were cultivated. Cacao plantations were the most profitable, as world demand for chocolate rose. It is here that Humboldt is said to have developed his idea of human-induced climate change. Investigating evidence of a rapid fall in the water level of the valley's Lake Valencia, Humboldt credited the desiccation to the clearance of tree cover and to the inability of the exposed soils to retain water. With their clear cutting of trees, the agriculturalists were removing the woodland's "threefold" moderating influence upon temperature: cooling shade, evaporation and radiation. Humboldt visited the mission at
Caripe and explored the
Guácharo cavern, where he found the
oilbird, which he was to make known to science as
Steatornis caripensis. He also described the
Guanoco asphalt lake as "The spring of the good priest" ("
Quelle des guten Priesters"). Returning to Cumaná, Humboldt observed, on the night of 11–12 November, a remarkable
meteor shower (the
Leonids). He proceeded with Bonpland to
Caracas where he climbed the
Avila mount with the young poet
Andrés Bello, the former tutor of
Simón Bolívar, who later became the leader of independence in northern South America. Humboldt met the Venezuelan Bolívar himself in 1804 in Paris and spent time with him in Rome. The documentary record does not support the supposition that Humboldt inspired Bolívar to participate in the struggle for independence, but it does indicate Bolívar's admiration for Humboldt's production of new knowledge on Spanish America. In February 1800, Humboldt and Bonpland left the coast with the purpose of exploring the course of the
Orinoco River and its tributaries. This trip, which lasted four months and covered of wild and largely uninhabited country, had an aim of establishing the existence of the
Casiquiare canal (a communication between the water systems of the rivers Orinoco and
Amazon). Although, unbeknownst to Humboldt, this existence had been established decades before, his expedition had the important results of determining the exact position of the
bifurcation,). Around 19 March 1800, Humboldt and Bonpland discovered dangerous
electric eels, whose shock could kill a man. To catch them, locals suggested they drive wild horses into the river, which brought the eels out from the river mud, and resulted in a violent confrontation of eels and horses, some of which died. Humboldt and Bonpland captured and dissected some eels, which retained their ability to shock; both received potentially dangerous electric shocks during their investigations. The encounter made Humboldt think more deeply about electricity and magnetism, typical of his ability to extrapolate from an observation to more general principles. Humboldt returned to the incident in several of his later writings, including his travelogue
Personal Narrative (1814–29),
Views of Nature (1807), and
Aspects of Nature (1849). Two months later, they explored the territory of the Maipures and that of the then-recently extinct Atures Indians. Humboldt laid to rest the persistent myth of
Walter Raleigh's
Lake Parime by proposing that the seasonal flooding of the
Rupununi savannah had been misidentified as a lake.
Cuba, 1800, 1804 On 24 November 1800, the two friends set sail for Cuba, landing on 19 December, where they met fellow botanist and
plant collector John Fraser. Fraser and his son had been shipwrecked off the Cuban coast, and did not have a license to be in the Spanish Indies. Humboldt, who was already in Cuba, interceded with crown officials in Havana, as well as giving them money and clothing. Fraser obtained permission to remain in Cuba and explore. Humboldt entrusted Fraser with taking two cases of Humboldt and Bonpland's botanical specimens to England when he returned, for eventual conveyance to the German botanist Willdenow in Berlin. Humboldt and Bonpland stayed in Cuba until 5 March 1801, when they left for the mainland of northern South America again, arriving there on 30 March. Humboldt is considered to be the "second discoverer of Cuba" due to the scientific and social research he conducted on this Spanish colony. During an initial three-month stay at
Havana, his first tasks were to survey that city properly and the nearby towns of
Guanabacoa,
Regla, and
Bejucal. He befriended Cuban landowner and thinker
Francisco de Arango y Parreño; together they visited the area in south Havana, the valleys of
Matanzas Province, and the
Valley of the Sugar Mills in
Trinidad. Those three areas were, at the time, the first frontier of sugar production in the island. During those trips, Humboldt collected statistical information on Cuba's population, production, technology and trade, and with Arango, made suggestions for enhancing them. He predicted that the agricultural and commercial potential of Cuba was huge and could be vastly improved with proper leadership in the future. On their way back to Europe from the Americas, Humboldt and Bonpland stopped again in Cuba, leaving from the port of Veracruz and arriving in Cuba on 7 January 1804, staying until 29 April 1804. In Cuba, he collected plant material and made extensive notes. During this time, he socialized with his scientific and landowner friends, conducted mineralogical surveys, and finished his vast collection of the island's flora and fauna that he eventually published as ''Essai politique sur l'îsle de Cuba''.
The Andes, 1801–1803 volcano, painting by
Friedrich Georg Weitsch (1810) After their first stay in Cuba of three months, they returned to the mainland at
Cartagena de Indias (now in Colombia), a major center of trade in northern South America. Ascending the swollen stream of the
Magdalena River to Honda, they arrived in Bogotá on 6 July 1801, where they met the Spanish botanist
José Celestino Mutis, head of the Royal Botanical Expedition to New Granada, staying there until 8 September 1801. Mutis was generous with his time and gave Humboldt access to the huge pictorial record he had compiled since 1783. Mutis was based in Bogotá, but as with other Spanish expeditions, he had access to local knowledge and a workshop of artists, who created highly accurate and detailed images. This type of careful recording meant that even if specimens were not available to study at a distance, "because the images travelled, the botanists did not have to". Humboldt was astounded at Mutis's accomplishment; when Humboldt published his first volume on botany, he dedicated it to Mutis "as a simple mark of our admiration and acknowledgement". Humboldt had hopes of connecting with the French sailing expedition of Baudin, now finally underway, so Bonpland and Humboldt hurried to Ecuador. They crossed the frozen ridges of the
Cordillera Real and reached
Quito on 6 January 1802, after a tedious and difficult journey. Their stay in Ecuador was marked by the ascent of the active volcano
Pichincha and their climb of the extinct, snow-capped volcano
Chimborazo, where Humboldt and his party, consisting of himself, Bonpland, a number of Indians and the Ecuadorian nobleman
Carlos Montúfar, reached an altitude of . This was a world record at the time, higher even than had been ascended in a balloon, (for a westerner—
Incas had climbed much higher altitudes centuries before), but 1000 feet short of the summit. Humboldt's journey concluded with an expedition to the sources of the Amazon
en route for
Lima, Peru. At
Callao, the main port for Peru, Humboldt observed the
transit of Mercury on 9 November and studied the fertilizing properties of
guano, rich in nitrogen, the subsequent introduction of which into Europe was due mainly to his writings. Humboldt and Bonpland arrived in Mexico City, having been officially welcomed via a letter from the king's representative in New Spain, Viceroy Don
José de Iturrigaray. Humboldt was also given a special passport to travel throughout New Spain and letters of introduction to intendants, the highest officials in New Spain's administrative districts (intendancies). This official aid to Humboldt allowed him to have access to crown records, mines, landed estates, canals, and Mexican antiquities from the prehispanic era. Humboldt read the writings of Bishop-elect of the important diocese of Michoacan
Manuel Abad y Queipo, a
classical liberal, that were directed to the crown for the improvement of New Spain. They spent the year in the viceroyalty, traveling to different Mexican cities in the central plateau and the northern mining region. The first journey was from Acapulco to Mexico City, through what is now the Mexican state of
Guerrero. The route was suitable only for mule train, and all along the way, Humboldt took measurements of elevation. When he left Mexico a year later in 1804, from the east coast port of Veracruz, he took a similar set of measures, which resulted in a chart in the
Political Essay, the physical plan of Mexico with the dangers of the road from Acapulco to Mexico City, and from Mexico City to Veracruz. This visual depiction of elevation was part of Humboldt's general insistence that the data he collected be presented in a way more easily understood than statistical charts. A great deal of his success in gaining a more general readership for his works was his understanding that "anything that has to do with extent or quantity can be represented geometrically. Statistical projections [charts and graphs], which speak to the senses without tiring the intellect have the advantage of bringing attention to a large number of important facts". Humboldt was impressed with Mexico City, which at the time was the largest city in the Americas, and one that could be counted as modern. He declared "no city of the new continent, without even excepting those of the United States, can display such great and solid scientific establishments as the capital of Mexico". He pointed to the
Royal College of Mines, the
Royal Botanical Garden and the
Royal Academy of San Carlos as exemplars of a metropolitan capital in touch with the latest developments on the continent and insisting on its modernity. He also recognized important
criollo savants in Mexico, including
José Antonio de Alzate y Ramírez, who died in 1799, just before Humboldt's visit; Miguel Velásquez de León; and
Antonio de León y Gama. Humboldt spent time at the Valenciana silver mine in
Guanajuato, central New Spain, at the time the most important in the Spanish empire. The bicentennial of his visit in Guanajuato was celebrated with a conference at the
University of Guanajuato, with Mexican academics highlighting various aspects of his impact on the city. Humboldt could have simply examined the geology of the fabulously rich mine, but he took the opportunity to study the entire mining complex as well as analyze mining statistics of its output. His report on silver mining is a major contribution, and considered the strongest and best informed section of his
Political Essay. Although Humboldt was himself a trained geologist and mining inspector, he drew on mining experts in Mexico. One was
Fausto Elhuyar, then head of the General Mining Court in Mexico City, who, like Humboldt was trained in Freiberg. Another was
Andrés Manuel del Río, director of Royal College of Mines, whom Humboldt knew when they were both students in Freiberg. The Bourbon monarchs had established the mining court and the college to elevate mining as a profession, since revenues from silver constituted the crown's largest source of income. Humboldt also consulted other German mining experts, who were already in Mexico. While Humboldt was a welcome foreign scientist and mining expert, the Spanish crown had established fertile ground for Humboldt's investigations into mining. Spanish America's ancient civilizations were a source of interest for Humboldt, who included images of Mexican manuscripts (or codices) and Inca ruins in his richly illustrated ''Vues des cordillères et monuments des peuples indigènes de l'Amerique'' (1810–1813), the most experimental of Humboldt's publications, since it does not have "a single ordering principle" but his opinions and contentions based on observation. For Humboldt, a key question was the influence of climate on the development of these civilizations. When he published his
Vues des cordillères, he included a color image of the
Aztec calendar stone (which had been discovered in 1790 buried in the
main plaza of Mexico City), along with select drawings of the
Dresden Codex and others he sought out later in European collections. His aim was to muster evidence that these pictorial and sculptural images could allow the reconstruction of prehispanic history. He sought out Mexican experts in the interpretation of sources from there, especially Antonio Pichardo, who was the literary executor of
Antonio de León y Gama's work. For American-born Spaniards (
criollos) who were seeking sources of pride in Mexico's ancient past, Humboldt's recognition of these ancient works and dissemination in his publications was a boon. He read the work of exiled Jesuit
Francisco Javier Clavijero, which celebrated Mexico's prehispanic civilization, and which Humboldt invoked to counter the pejorative assertions about the new world by Buffon, de Pauw, and Raynal. Humboldt ultimately viewed both the prehispanic realms of Mexico and Peru as despotic and barbaric. However, he also drew attention to indigenous monuments and artifacts as cultural productions that had "both ... historical
and artistic significance". One of his most widely read publications resulting from his travels and investigations in Spanish America was the
Essai politique sur le royaum de la Nouvelle Espagne, quickly translated to English as
Political Essay on the Kingdom of New Spain (1811). This treatise was the result of Humboldt's own investigations as well as the generosity of Spanish colonial officials for statistical data.
The United States, 1804 Leaving from Cuba, Humboldt decided to take an unplanned short visit to the United States. Knowing that the current U.S. president,
Thomas Jefferson, was himself a scientist, Humboldt wrote to him saying that he would be in the United States. Jefferson warmly replied, inviting him to visit the
White House in the nation's new capital. In his letter Humboldt had gained Jefferson's interest by mentioning that he had discovered
mammoth teeth near the Equator. Jefferson had previously written that he believed mammoths had never lived so far south. Humboldt had also hinted at his knowledge of New Spain. Arriving in
Philadelphia, which was a center of learning in the U.S., Humboldt met with some of the major scientific figures of the era, including chemist and anatomist
Caspar Wistar, who pushed for compulsory smallpox vaccination, and botanist
Benjamin Smith Barton, as well as physician
Benjamin Rush, a signer of the
Declaration of Independence, who wished to hear about
cinchona bark from a South American tree, which cured fevers. Humboldt's treatise on cinchona was published in English in 1821. After arriving in Washington D.C, Humboldt held numerous intense discussions with Jefferson on both scientific matters and also his year-long stay in New Spain. Jefferson had only recently concluded the
Louisiana Purchase, which now placed New Spain on the southwest border of the United States. The Spanish minister in Washington, D.C. had declined to furnish the U.S. government with information about Spanish territories, and access to the territories was strictly controlled. Humboldt was able to supply Jefferson with the latest information on the population, trade agriculture and military of New Spain. This information would later be the basis for his
Essay on the Political Kingdom of New Spain (1810). Jefferson was unsure of where the border of the newly-purchased
Louisiana was precisely, and Humboldt wrote him a two-page report on the matter. Jefferson would later refer to Humboldt as "the most scientific man of the age".
Albert Gallatin, Secretary of the Treasury, said of Humboldt "I was delighted and swallowed more information of various kinds in less than two hours than I had for two years past in all I had read or heard." Gallatin, in turn, supplied Humboldt with information he sought on the United States. A government-funded project to digitize the Spanish American expedition as well as his later Russian expedition has been undertaken (2014–2017) by the University of Potsdam and the German State Library–Prussian Cultural Heritage Foundation.
Achievements of the Hispanic American expedition Humboldt's decades' long endeavor to publish the results of this expedition not only resulted in multiple volumes, but also made his international reputation in scientific circles. Humboldt came to be well-known with the reading public as well, with popular, densely illustrated, condensed versions of his work in multiple languages. Bonpland, his fellow scientist and collaborator on the expedition, collected botanical specimens and preserved them, but unlike Humboldt who had a passion to publish, Bonpland had to be prodded to do the formal descriptions. Many scientific travelers and explorers produced huge visual records which remained unseen by the general public until the late nineteenth century. In the case of the Malaspina Expedition, it was not until the late twentieth century when Mutis's botanical, some 12,000 drawings from New Granada, was published. Humboldt, by contrast, published immediately and continuously, using and ultimately exhausting his personal fortune, to produce both scientific and popular texts. Humboldt's name and fame were made by his travels to Spanish America, particularly his publication of the
Political Essay on the Kingdom of New Spain; his image as the premier European scientist was a later development. For the Bourbon crown, which had authorized the expedition, the returns were not only tremendous in terms of sheer volume of data on their New World realms, but in dispelling the vague and pejorative assessments of the New World by
Guillaume-Thomas Raynal,
Georges-Louis Leclerc, Comte de Buffon, and
William Robertson. The achievements of the Bourbon regime, especially in New Spain, were evident in the precise data Humboldt systematized and published. This memorable expedition may be regarded as having laid the foundation of the sciences of
physical geography,
plant geography, and
meteorology. Key to that was Humboldt's meticulous and systematic measurement of phenomena with the most advanced instruments then available. He closely observed plant and animal species in situ, not just in isolation, noting all elements in relation to one other. He collected specimens of plants and animals, dividing the growing collection so that if a portion was lost, other parts might survive. , 1805, who met Humboldt when he visited the U.S. in 1804 Humboldt saw the need for an approach to science that could account for the harmony of nature among the diversity of the physical world. For Humboldt, "the unity of nature" meant that it was the interrelation of all
physical sciences—such as the conjoining between
biology,
meteorology and
geology—that determined where specific plants grew. He found these relationships by unraveling myriad, painstakingly collected data, data extensive enough that it became an enduring foundation upon which others could base their work. Humboldt viewed nature
holistically, and tried to explain natural phenomena without the appeal to religious dogma. He believed in the central importance of observation, and as a consequence had amassed a vast array of the most sophisticated scientific instruments then available. Each had its own velvet lined box and was the most accurate and portable of its time; nothing quantifiable escaped measurement. According to Humboldt, everything should be measured with the finest and most modern instruments and sophisticated techniques available, for that collected data was the basis of all scientific understanding. This quantitative methodology would become known as
Humboldtian science. Humboldt wrote "Nature herself is sublimely eloquent. The stars as they sparkle in firmament fill us with delight and ecstasy, and yet they all move in orbit marked out with mathematical precision." However,
Andreas Daum has recently revisited the concept of Humboldtian Science and set it apart from "Humboldt's science". . His
Essay on the Geography of Plants (published first in French and then German, both in 1807) was based on the then novel idea of studying the distribution of organic life as affected by varying physical conditions. The Chimborazo map displayed complex information in an accessible fashion. The map was the basis for comparison with other major peaks. "The Naturgemälde showed for the first time that nature was a global force with corresponding climate zones across continents." Another assessment of the map is that it "marked the beginning of a new era of environmental science, not only of mountain ecology but also of global-scale biogeophysical patterns and processes." By his delineation (in 1817) of
isothermal lines, he at once suggested the idea and devised the means of comparing the climatic conditions of various countries. He first investigated the rate of decrease in mean temperature with the increase in elevation above sea level, and afforded, by his inquiries regarding the origin of tropical storms, the earliest clue to the detection of the more complicated law governing atmospheric disturbances in higher latitudes. This was a major contribution to climatology. His discovery of the decrease in intensity of Earth's
magnetic field from the poles to the equator was communicated to the Paris Institute in a memoir read by him on 7 December 1804. Its importance was attested by the speedy emergence of rival claims. The U.S. was keen to see his maps and statistics on New Spain, since they had implication for territorial claims following the Louisiana Purchase. Later in life, Humboldt published three volumes (1836–39) examining sources that dealt with the early voyages to the Americas, pursuing his interest in nautical astronomy in the fifteenth and sixteenth centuries. His research yielded the origin of the name "America", put on a map of the Americas by
Martin Waldseemüller. , an example of his detailed drawing Humboldt conducted a census of the indigenous and European inhabitants in
New Spain, publishing a schematized drawing of racial types and populations distribution, grouping them by region and social characteristics. He estimated the population to be six million individuals. He estimated Indians to be forty percent of New Spain's population, but their distribution being uneven; the most dense were in the center and south of Mexico, the least dense in the north. He presented these data in chart form, for easier understanding. He also surveyed the non-Indian population, categorized as Whites (Spaniards),
Negroes, and castes (
castas). American-born Spaniards, so-called
creoles had been
painting depictions of mixed-race family groupings in the eighteenth century, showing father of one racial category, mother of another, and the offspring in a third category in hierarchical order, so racial hierarchy was an essential way elites viewed Mexican society. Humboldt reported that American-born Spaniards were legally racial equals of
those born in Spain, but the crown policy since the Bourbons took the Spanish throne privileged those born in Iberia. Humboldt observed that "the most miserable European, without education and without intellectual cultivation, thinks himself superior to whites born in the new continent". The truth in this assertion, and the conclusions derived from them, have been often disputed as superficial, or politically motivated, by some authors, considering that between 40% and 60% of high offices in the new world were held by creoles. The enmity between some creoles and the peninsular-born whites increasingly became an issue in the late period of Spanish rule, with creoles increasingly alienated from the crown. Humboldt's assessment was that royal government abuses and the example of
a new model of rule in the United States were eroding the unity of whites in New Spain. Humboldt's writings on race in New Spain were shaped by the memorials of the
classical liberal, enlightened Bishop-elect of Michoacán,
Manuel Abad y Queipo, who personally presented Humboldt with his printed memorials to the Spanish crown critiquing social and economic conditions and his recommendations for eliminating them. The further assessment is that he largely neglected the human societies amidst nature. Views of indigenous peoples as 'savage' or 'unimportant' leaves them out of the historical picture. The editing and publication of the encyclopedic mass of scientific, political and archaeological material that had been collected by him during his absence from Europe was now Humboldt's most urgent desire. After a short trip to Italy with
Joseph Louis Gay-Lussac for the purpose of investigating the law of
magnetic declination and a stay of two and a half years in Berlin, in the spring of 1808, he settled in Paris. His purpose for being located there was to secure the scientific cooperation required for bringing his great work through the press. This colossal task, which he at first hoped would occupy but two years, eventually cost him twenty-one, and even then it remained incomplete. ==Scholarly and public recognition==