linguistic:voice_change, stylistic:tone, linguistic:translation, information:highlighting
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, and even 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.

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."

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. This was most famously depicted in his published cross-section of Chimborazo, approximately two feet by three feet (54 cm x 84 cm) color pictorial, he called Ein Naturgemälde der Anden and what is also called the Chimborazo Map. It was a fold-out at the back of the publication. Humboldt first sketched the map when he was in South America, which included written descriptions on either side of the cross-section of Chimborazo. These detailed the information on temperature, altitude, humidity, atmosphere pressure, and the animal and plants (with their scientific names) found at each elevation. Plants from the same genus appear at different elevations. The depiction is on an east-west axis going from the Pacific coast lowlands to the Andean range of which Chimborazo was a part, and the eastern Amazonian basin. Humboldt showed the three zones of coast, mountains, and Amazonia, based on his own observations, but he also drew on existing Spanish sources, particularly Pedro Cieza de León, which he explicitly referred to. The Spanish American scientist Francisco José de Caldas had also measured and observed mountain environments and had earlier come to similar ideas about environmental factors in the distribution of life forms. Humboldt was thus not putting forward something entirely new, but it is argued that his finding is not derivative either. 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.

His services to geology were based on his attentive study of the volcanoes of the Andes and Mexico, which he observed and sketched, climbed, and measured with a variety of instruments. By climbing Chimborazo, he established an altitude record which became the basis for measurement of other volcanoes in the Andes and the Himalayas. As with other aspects of his investigations, he developed methods to show his synthesized results visually, using the graphic method of geologic-cross sections. He showed that volcanoes fell naturally into linear groups, presumably corresponding with vast subterranean fissures; and by his demonstration of the igneous origin of rocks previously held to be of aqueous formation, he contributed largely to the elimination of erroneous views, such as Neptunism.

Humboldt was a significant contributor to cartography, creating maps, particularly of New Spain, that became the template for later mapmakers in Mexico. His careful recording of latitude and longitude led to accurate maps of Mexico, the port of Acapulco, the port of Veracruz, and the Valley of Mexico, and a map showing trade patterns among continents. His maps also included schematic information on geography, converting areas of administrative districts (intendancies) using proportional squares. 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.

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.

One scholar says that his writings contain fantastical descriptions of America, while leaving out its inhabitants, stating that Humboldt, coming from the Romantic school of thought, believed '... nature is perfect till man deforms it with care'. 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. Other scholars counter that Humboldt dedicated large parts of his work to describing the conditions of slaves, indigenous peoples, mixed-race castas, and society in general. He often showed his disgust for the slavery and inhumane conditions in which indigenous peoples and others were treated and he often criticized Spanish colonial policies.

Humboldt was not primarily an artist, but he could draw well, allowing him to record a visual record of particular places and their natural environment. Many of his drawings became the basis for illustrations of his many scientific and general publications. Artists whom Humboldt influenced, such as Johann Moritz Rugendas, followed in his path and painted the same places Humboldt had visited and recorded, such as the basalt formations in Mexico, which was an illustration in his Vues des Cordillères.

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.