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|Alexander von Humboldt|
Alexander von Humboldt, (detail) by Joseph Stieler, 1843
|Born||September 14, 1769|
|Died||May 6, 1859 (aged 89)|
|Known for||Biogeography, Kosmos (1845)|
|Alexander von Humboldt|
Alexander von Humboldt, (detail) by Joseph Stieler, 1843
|Born||September 14, 1769|
|Died||May 6, 1859 (aged 89)|
|Known for||Biogeography, Kosmos (1845)|
Friedrich Wilhelm Heinrich Alexander von Humboldt ( listen (help·info); September 14, 1769 – May 6, 1859) was a Prussian geographer, naturalist and explorer, and the younger brother of the Prussian minister, philosopher and linguist Wilhelm von Humboldt (1767–1835). Humboldt's quantitative work on botanical geography laid the foundation for the field of biogeography.
Between 1799 and 1804, Humboldt travelled extensively in Latin America, exploring and describing it for the first time from a modern scientific point of view. His description of the journey was written up and published in an enormous set of volumes over 21 years. He was one of the first to propose that the lands bordering the Atlantic Ocean were once joined (South America and Africa in particular). Later, his five-volume work, Kosmos (1845), attempted to unify the various branches of scientific knowledge. Humboldt supported and worked with other scientists, including Joseph-Louis Gay-Lussac, Justus von Liebig, Louis Agassiz, Matthew Fontaine Maury, Georg von Neumayer, and most notably, Aimé Bonpland, with whom he conducted much of his scientific exploration.
Humboldt was born in Berlin in the Margraviate of Brandenburg. His father, Alexander Georg von Humboldt, belonged to a prominent Pomeranian family; a major in the Prussian Army, he was rewarded for his services in the Seven Years' War with the post of Royal Chamberlain. He married the daughter of the Prussian general adjutant, von Schweder. In 1766, he married Maria Elizabeth Colomb, the widow of Baron von Hollwede, and they had two sons. The money of Baron von Holwede, left to his former wife, was instrumental in funding Alexander's explorations, contributing more than 70% of Alexander's income.
Due to his juvenile penchant for collecting and labelling plants, shells and insects, Alexander received the playful title of "the little apothecary". His father died in 1779, after which his mother saw to his education. Marked for a political career, he studied finance for six months at the University of Frankfurt (Oder); a year later, on April 25, 1789, he matriculated at Göttingen, then known for the lectures of C. G. Heyne and J. F. Blumenbach. His vast and varied interests were by this time fully developed, and during a vacation in 1789, he made a scientific excursion up the Rhine and produced the treatise Mineralogische Beobachtungen über einige Basalte am Rhein (Brunswick, 1790) (Mineralogic Observations on Several Basalts on the River Rhine).
Humboldt's passion for travel was confirmed by a friendship formed at Göttingen with Georg Forster, Heyne's son-in-law and the companion of Captain James Cook on Cook's second voyage. Thereafter, his talents were devoted to the purpose of preparing himself as a scientific explorer. With this emphasis, he studied commerce and foreign languages at Hamburg, geology at Technische Universität Bergakademie Freiberg under A. G. Werner, anatomy at Jena under J. C. Loder and astronomy and the use of scientific instruments under F. X. von Zach and J. G. Köhler. His researches into the vegetation of the mines of Freiberg led to the publication, in 1793, of his Florae Fribergensis Specimen. Long experimentation on muscular irritability, then recently discovered by Luigi Galvani, were contained in his Versuche über die gereizte Muskel- und Nervenfaser (Berlin, 1797) (Experiments on the Frayed Muscle and Nerve Fibres), enriched in the French translation with notes by Blumenbach.
In 1794 Humboldt was admitted to the famous Weimar coterie and contributed (June 7, 1795) to Schiller's new periodical, Die Horen, a philosophical allegory entitled Die Lebenskraft, oder der rhodische Genius. In the summer of 1790 he paid a short visit to England in the company of Forster. In 1792 and 1797 he was in Vienna; in 1795 he made a geological and botanical tour through Switzerland and Italy. He had obtained in the meantime official employment by appointment as assessor of mines at Berlin, February 29, 1792. Although this service to the state was regarded by him as only an apprenticeship to the service of science, he fulfilled its duties with such conspicuous ability that not only did he rise rapidly to the highest post in his department, but he was also entrusted with several important diplomatic missions. The death of his mother, on November 19, 1796, set him free to follow the bent of his genius, and severing his official connections, he waited for an opportunity to fulfil his long-cherished dream of travel.
On the postponement of Captain Nicolas Baudin's proposed voyage of circumnavigation, which he had been officially invited to accompany, Humboldt left Paris for Marseille with Aimé Bonpland, the designated botanist of the frustrated expedition, hoping to join Napoleon Bonaparte in Egypt. Means of transport, however, were not forthcoming, and the two travellers eventually found their way to Madrid, where the unexpected patronage of the minister Don Mariano Luis de Urquijo convinced them to make Spanish America the scene of their explorations.
Armed with powerful recommendations from the King of Spain, they sailed in the Pizarro from A Coruña, on June 5, 1799, stopped six days on the island of Tenerife to climb the volcano Teide, and landed at Cumaná, Venezuela, on July 16. Humboldt visited the mission at Caripe and explored the Guácharo cavern, where he found the oil-bird, which he was to make known to science as Steatornis caripensis. Returning to Cumaná, Humboldt observed, on the night of November 11–12, a remarkable meteor shower (the Leonids). He proceeded with Bonpland to Caracas where he would climb the Avila mount with Andrés Bello. In February 1800, Humboldt and Bonpland left the coast with the purpose of exploring the course of the Orinoco River. This trip, which lasted four months and covered 1,725 miles (2,776 km) of wild and largely uninhabited country, had the important result of establishing the existence of the Casiquiare canal (a communication between the water-systems of the rivers Orinoco and Amazon), and of determining the exact position of the bifurcation, as well as documenting the life of several native tribes such as the Maipures and their extinct rivals the Atures (several words of the latter tribe were transferred to Humboldt by one parrot). Around March 19, 1800, von Humboldt and Bonpland discovered and captured some electric eels. They both received potentially dangerous electric shocks during their investigations. Two months later they explored the territory of the Maypures and that of the then recently extinct Aturès Indians.
On November 24, the two friends set sail for Cuba where they met fellow botanist and plant collector John Fraser, and after a stay of some months they regained the mainland at Cartagena, Colombia. Ascending the swollen stream of the Magdalena River and crossing the frozen ridges of the Cordillera Real, they reached Quito on January 6, 1802, after a tedious and difficult journey. Their stay there was marked by the ascent of Pichincha and an attempt on Chimborazo. Humboldt and his party reached an altitude of 19,286 feet (5,878 m), a world record at the time. The journey concluded with an expedition to the sources of the Amazon en route for Lima, Peru. At Callao, Humboldt observed the transit of Mercury on November 9, and studied the fertilizing properties of guano, the subsequent introduction of which into Europe was due mainly to his writings. A tempestuous sea-voyage brought them to Mexico, where they resided for a year, travelling to different cities.
Next, Humboldt made a short visit to the United States, staying in the White House as a guest of President Thomas Jefferson. Jefferson, a scientist himself, was delighted to have Humboldt as a guest and the two held numerous intense discussions on scientific matters. After six weeks, Humboldt set sail for Europe from the mouth of the Delaware and landed at Bordeaux on August 3, 1804.
This memorable expedition may be regarded as having laid the foundation of the sciences of physical geography and meteorology. 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; while his essay on the geography of plants was based on the then novel idea of studying the distribution of organic life as affected by varying physical conditions. 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 December 7, 1804, and its importance was attested by the speedy emergence of rival claims. His services to geology were based mainly on his attentive study of the volcanoes of the New World. He showed that they 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 is considered to be the "second discoverer of Cuba" due to all the scientific and social research he conducted on this Spanish colony. During an initial three-month stay at Havana, his first tasks were to properly survey that city and the nearby towns of Guanabacoa, Regla and Bejucal. He befriended Cuban landowner and thinker Francisco Arango y Parreño; together they visited the Guines 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. After traveling to the United States, Humboldt returned to Cuba for a second, shorter stay in April 1804. 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.
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 Gay-Lussac for the purpose of investigating the law of magnetic declination and a sojourn of two and a half years in his native city, he finally, in the spring of 1808, settled in Paris with the purpose of securing 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. In these early years in Paris, he shared accommodation and a laboratory with his former rival, and now friend, Joseph-Louis Gay-Lussac, both working together on the analysis of gases and the composition of the atmosphere.
Alexander von Humboldt thought an approach to science was needed 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 unravelling 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 critics say his writings contain fantastical descriptions of America, while leaving out its inhabitants. They claim Humboldt, coming from the Romantic school of thought, believed '... nature is perfect till man deforms it with care.' In this line of thinking, they think he largely neglected the human societies amidst this nature. The writing style that describes the 'new world' without people is a trend among explorers both of the past and present. Views of indigenous peoples as 'savage' or 'unimportant' leaves them out of the historical picture. In reality Humboldt dedicated large parts of his work to describing the conditions of slaves, indigenous peoples 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 the colonial policies. Some of Humboldt's descriptions or assumptions were not accurate.
Humboldt was now one of the most famous men in Europe. The acclaimed American painter Rembrandt Peale painted him during his European stay, between 1808 and 1810, as one of the most prominent figures in Europe at the time. A chorus of applause greeted him from every side. Academies, both native and foreign, were eager to enrol him among their members. He was elected a foreign member of the Royal Swedish Academy of Sciences in 1810. King Frederick William III of Prussia conferred upon him the honour, without exacting the duties, attached to the post of royal chamberlain, together with a pension of 2,500 thalers, afterwards doubled. He refused the appointment of Prussian minister of public instruction in 1810. In 1814 he accompanied the allied sovereigns to London. Three years later he was summoned by the king of Prussia to attend him at the congress of Aachen. Humboldt was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1822. Again in the autumn of 1822 he accompanied the same monarch to the Congress of Verona, proceeded thence with the royal party to Rome and Naples and returned to Paris in the spring of 1823.
Humboldt had long regarded the French capital as his true home. There he found not only scientific sympathy, but the social stimulus which his vigorous and healthy mind eagerly craved. He was equally in his element as the lion of the salons and as the savant of the Institut de France and the observatory. During that time he met in 1818, the young and brilliant Peruvian student of the Royal Mining School of Paris, Mariano Eduardo de Rivero y Ustariz. They became good friends. Subsequently von Humboldt acted as a mentor of the career of this promising Peruvian scientist. Thus, when at last he received from his sovereign a summons to join his court at Berlin, he obeyed indeed, but with deep and lasting regret. The provincialism of his native city was odious to him. He never ceased to rail against the bigotry without religion[clarification needed], aestheticism without culture, and philosophy without common sense, which he found dominant on the banks of the Spree. The unremitting benefits and sincere attachment of two well-meaning princes secured his gratitude but could not appease his discontent. At first he sought relief from the "nebulous atmosphere" of his new abode by frequent visits to Paris; but as years advanced, his excursions were reduced to accompanying the monotonous "oscillations" of the court between Potsdam and Berlin. On May 12, 1827, he settled permanently in the Prussian capital, where his first efforts were directed towards the furtherance of the science of terrestrial magnetism. For many years, it had been one of his favourite schemes to secure, by means of simultaneous observations at distant points, a thorough investigation of the nature and law of "magnetic storms" (a term invented by him to designate abnormal disturbances of Earth's magnetism). The meeting at Berlin, on September 18, 1828, of a newly formed scientific association, of which he was elected president, gave him the opportunity of setting on foot an extensive system of research in combination with his diligent personal observations. His appeal to the Russian government, in 1829, led to the establishment of a line of magnetic and meteorological stations across northern Asia. Meanwhile his letter to the Duke of Sussex, then (April 1836) president of the Royal Society, secured for the undertaking, the wide basis of the British dominions.
The Encyclopædia Britannica, Eleventh Edition, observes, "Thus that scientific conspiracy of nations which is one of the noblest fruits of modern civilization was by his exertions first successfully organized." However, earlier examples of international scientific cooperation exist, notably the 18th-century observations of the transits of Venus.
Then President of Mexico, Benito Juárez, gave him honorary Mexican citizenship.
In 1811, and again in 1818, projects of Asiatic exploration were proposed to Humboldt, first by the Russian government, and afterwards by the Prussian government; but on each occasion, untoward circumstances interposed, and it was not until he had begun his sixtieth year that he resumed his early role of traveller in the interests of science. Between May and November 1829, he, together with his chosen associates, Gustav Rose and C. G. Ehrenberg, traversed the wide expanse of the Russian empire from the Neva to the Yenesei, accomplishing in twenty-five weeks a distance of 9,614 miles (15,472 km). The journey, however, though carried out with all the advantages afforded by the immediate patronage of the Russian government, was too rapid to be profitable. The correction of the prevalent exaggerated estimate of the height of the Central Asian plateau, and the discovery of diamonds in the gold-washings of the Ural, a result which Humboldt's Brazilian experiences enabled him to predict, and by predicting to secure.
Between 1830 and 1848 von Humboldt was frequently employed in diplomatic missions to the court of Louis Philippe, with whom he always maintained the most cordial personal relations.
His brother, Wilhelm von Humboldt, died in Alexander's arms on April 8, 1835. The death saddened the later years of his life; Alexander lamented that he had lost half of himself with the death of his brother.
Upon the accession of the crown prince Frederick William IV in June 1840, Humboldt's favour at court increased. Indeed, the new king's craving for Humboldt's company became at times so importunate as to leave him only a few waking hours to work on his writing.
The first two volumes of the Kosmos were published between the years 1845 and 1847. Humboldt had long intended to write a comprehensive work about geography and the natural sciences. The writing took shape in lectures he delivered before the University of Berlin in the winter of 1827–28. These lectures would form "the cartoon for the great fresco of the [K]osmos". The work attempted to unify the sciences then known in a Kantian framework. With inspiration from German Romanticism, Humboldt sought to create a compendium of the world's environment.
He spent the last decade of his long life — as he called them, his "improbable" years — continuing this work. The third and fourth volumes were published in 1850–58; a fragment of a fifth appeared posthumously in 1862.
Kosmos was very popular in Britain and America. In 1849 a German newspaper commented that in England two of the three different translations were made by women, "while in Germany most of the men do not understand it." The first translation by Augustin Pritchard — published anonymously by Mr. Baillière (volume I in 1845 and volume II in 1848) — suffered from being hurriedly made. In a letter Humboldt said of it: "It will damage my reputation. All the charm of my description is destroyed by an English sounding like Sanskrit."
The other two translations were made by Mrs. Sabine under the superintendence of her husband Col. Edward Sabine (4 volumes 1846–1858), and by Miss E.C. Otté (5 volumes 1849–1858, the only complete translation of the 4 German volumes). These three translations were also published in America. The numbering of the volumes differs between the German and the English editions. Volume 3 of the German edition corresponds to the volumes 3 and 4 of the English translation, as the German volume appeared in 2 parts in 1850 and 1851. Volume 5 of the German edition was not translated until 1981, again by a woman. Miss Otté's translation benefited from a detailed table of contents, and an index for every volume; of the German edition only volumes 4 and 5 had a (extremely short) tables of contents, and the index to the whole work only appeared with volume 5 in 1862.
Not so well known in Germany is the atlas belonging to the German edition of the Cosmos "Berghaus' Physikalischer Atlas", better known as the pirated version by Traugott Bromme under the title "Atlas zu Alexander von Humboldt's Kosmos" (Stuttgart 1861). In Britain Heinrich Berghaus planned to publish together with Alexander Keith Johnston a "Physical Atlas". But later Johnston published it alone under the title "The Physical Atlas of Natural Phenomena". In Britain its connection to the Cosmos seems not have been recognized.
On February 24, 1857, Humboldt suffered a minor stroke, which passed without perceptible symptoms. It was not until the winter of 1858–1859 that his strength began to decline, and that spring, on May 6, he died quietly in Berlin at the age of 89. The honours which had been showered on him during life continued after his death. His remains, prior to being interred in the family resting-place at Tegel, were conveyed in state through the streets of Berlin, and received by the prince-regent at the door of the cathedral.
The first centenary of Humboldt's birth was celebrated on September 14, 1869, with great enthusiasm in both the New and Old Worlds. Numerous monuments were constructed in his honour, such as Humboldt Park, Chicago, planned that year and constructed shortly after the Chicago fire. Newly explored regions and species named after Humboldt, as discussed below, also bear witness to his wide fame and popularity.
Much of Humboldt's private life remains a mystery because he destroyed his private letters.
In 1908 the sexual researcher Paul Näcke, who worked with outspoken gay activist Magnus Hirschfeld, gathered reminiscences of him from people who recalled his participation in the homosexual subculture of Berlin. A travelling companion, the pious Francisco José de Caldas, accused him of frequenting houses where 'impure love reigned', of making friends with 'obscene dissolute youths', and giving vent to 'shameful passions of his heart'. But author Robert F. Aldrich concludes hesitantly: "As for so many men of his age, a definite answer is impossible."
Throughout his life Humboldt formed strong emotional attachments to men. In a letter to Reinhard von Haeften, a soldier, he wrote: "I know that I live only through you, my good precious Reinhard, and that I can only be happy in your presence." He never married, yet there were at least two notable occasions where he seemed to have been drawn to the opposite sex. The first was an adolescent infatuation with Henriette Herz, the beautiful wife of Marcus Herz, his mentor, and the second was a short lived but intimate relationship with a woman named Pauline Wiesel in 1808 Paris. He was strongly attached to his brother's family. Four years before his death, he executed a deed of gift transferring the absolute possession of his entire property to an old family servant named Seifert.
Humboldt made many friends and had a reputation for widespread benevolence. He showed zeal for the improvement of the condition of the miners in Galicia and Franconia, detestation of slavery, and patronage of rising men of science.
As a consequence of his explorations, von Humboldt described many geographical features and species of life that were hitherto unknown to Europeans. Species named after him include:
Features named after him include the following:
The following places are named for Humboldt:
Alexander Von Humboldt also lends his name to a prominent lecture series in Human geography in the Netherlands (hosted by the Radboud University Nijmegen). It is the Dutch equivalent of the widely known annual Hettner lectures at the University of Heidelberg.
After his death, his friends and colleagues created the Alexander von Humboldt Foundation (Stiftung in German) to continue von Humboldt's generous support of young scientists. Although the original endowment was lost in the German hyperinflation of the 1920s, and again as a result of World War II, the Foundation has been re-endowed by the German government to award young scientists and distinguished senior scientists from abroad. It plays an important role in attracting foreign researchers to work in Germany and enabling German researchers to work abroad for a period
Charles Darwin made frequent reference to Humboldt's work in his Voyage of the Beagle, where Darwin described his own scientific exploration of the Americas. In one note, he placed Humboldt first on the "list of American travellers". When this Journal was published, Darwin sent a copy to Humboldt, who responded "You told me in your kind letter that, when you were young, the manner in which I studied and depicted nature in the torrid zones contributed toward exciting in you the ardour and desire to travel in distant lands. Considering the importance of your work, Sir, this may be the greatest success that my humble work could bring." In his autobiography, Darwin recalled reading "with care and profound interest Humboldt's Personal Narrative" and finding it one of the two most influential books on his work, which had "stirred up in me a burning zeal to add even the most humble contribution to the noble structure of Natural Science."
Alexander von Humboldt is also a German ship named after the scientist originally built in 1906 by the German shipyard AG Weser at Bremen as Reserve Sonderburg. She was operated throughout the North and Baltic Seas until being retired in 1986. Subsequently she was converted into a three masted barque by the German shipyard Motorwerke Bremerhaven and was re-launched in 1988 as Alexander von Humboldt.
Wilhelm von Humboldt: "Alexander is destined to combine ideas and follow chains of thoughts which would otherwise have remained unknown for ages. His depth, his sharp mind and his incredible speed are a rare combination."
Hermann von Helmholtz: "During the first half of the present century we had an Alexander von Humboldt, who was able to scan the scientific knowledge of his time in its details, and to bring it within one vast generalization. At the present juncture, it is obviously very doubtful whether this task could be accomplished in a similar way, even by a mind with gifts so peculiarly suited for the purpose as Humboldt's was, and if all his time and work were devoted to the purpose."
Le voyage aux régions equinoxiales du Nouveau Continent, fait en 1799–1804, par Alexandre de Humboldt et Aimé Bonpland (Paris, 1807, etc.), consisted of thirty folio and quarto volumes, and comprised a considerable number of subordinate but important works. Among these may be enumerated
The Nova genera et species plantarum (7 vols. folio, 1815–1825), containing descriptions of above 4500 species of plants collected by Humboldt and Bonpland, was mainly compiled by Carl Sigismund Kunth; J. Oltmanns assisted in preparing the Recueil d'observations astronomiques (1808); Cuvier, Latreille, Valenciennes and Gay-Lussac cooperated in the Recueil d'observations de zoologie et d'anatomie comparée (1805–1833).
Humboldt's Ansichten der Natur (Stuttgart and Tübingen, 1808) went through three editions in his lifetime, and was translated into nearly every European language.
The results of his Asiatic journey were published in Fragments de géologie et de climatologie asiatiques (2 vols. 8vo, 1831), and in Asie centrale (3 vols. 8vo, 1843) an enlargement of the earlier work. The memoirs and papers read by him before scientific societies, or contributed by him to scientific periodicals, are too numerous for specification.
A 1992 essay entitled "Journey to the Top of the World" details Humboldt's South American exploration and America's interest in him. The essay is chapter one of David McCullough's book, Brave Companions: Portraits in History (Prentice Hall Press, 1992).
Gerard Helferich's 2004 biography Humboldt's Cosmos: Alexander von Humboldt and the Latin American Journey that Changed the World (Gotham Books, 2004) provides a descriptive account of Humboldt's journey through Latin America, using Humboldt's journals.
Daniel Kehlmann's 2005 novel Die Vermessung der Welt, translated into English by Carol Brown Janeway as Measuring the World in 2006, explores Humboldt's life through a lens of historical fiction, contrasting his character and contributions to science to those of Carl Friedrich Gauss.
Humboldt's effect on American scientists and environmentalists (Clarence King, Jeremiah N. Reynolds, George Wallace Melville, and John Muir) is examined in The Humboldt Current: Nineteenth Century Exploration and the Roots of American Environmentalism, by Aaron Sachs (Viking, 2006).
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