(b. London, England, 20 August 1831; d. Marz. Burgenland, Austria, 26 April 1914)
Although the name Suess had been known in Vienna since the fifteenth century, Eduard’s family came from Vogtland, a region surrounded by Bohemia, Saxony, and Bavaria. His father was the son of a minister at Bobenneukirchen, near the Bavarian frontier; his mother, Eleonore Zaekauer, was the daughter of a Prague banker. Suess’s father established a wool business in London, where Eduard, the couple’s second child, was born. The family left England in 1834 and traveled from the coast of the Netherlands to Prague by horse and carriage. As a child Eduard spoke English, and in order to preserve this knowledge he had an English instructor as well as German and French tutors. He therefore was able to enter the Gymnasium at an exceptionally early age.
In 1845 Suess’s father took over a leather factory, located near Vienna, which belonged to an ailing brother-in-law. During the revolutionary disturbances of 1848, Suess participated in demonstrations and joined the Légion Académique. He was elected to its committee and represented it on the Committee of Public Safety (Sicherheitsausschuss), of which he was the youngest member. His frequent participation in arbitration enabled him to learn to make decisions, assume responsibility for them, and justify them.
Treatment for an abscess on his foot obliged Suess to go to Prague, where he lived in his grandparents’ house. He thus escaped the upheaval in Vienna that put an end to the Metternich era.
While continuing his university studies at Prague, Suess also frequented the museums and made geological excursions to nearby fossil-rich areas. The samples he collected so stimulated his interest that he devoted himself increasingly to geology. When he returned to Vienna, he presented a manuscript on the graptolites to the Society of the Friends of Science, of which the leading member was Wilhelm Haidinger. This scientific work, Suess’s first, involved him in a minor dispute with the paleontologist Joachim Barrande; but their difference of opinion ended in friendship. Suess took charge of the society’s foreign correspondence and a portion of that of the Museum of Natural History. This work brought him valuable international contact.
A liver ailment compelled Suess to take a cure at Carlsbad (now Karlovy Vary). The region spurred him to analyze its differences from the countrysides around Prague and Vienna. (Comparisons of this sort long held Suess’s interest. He studied the granites and sketched the shapes of columns. As a result he was invited to write the chapter on geology for a tourist guide, his first published work.
Suess was imprisoned on 16 December 1850, probably as a result of a denunciation, but was released at the request of Haidinger, director of the Geological Survey. He then found regular studies at the Technical University to be impossible and devoted himself instead to geology at the Geological Survey and at the Imperial Mineralogical Collection, where he was assigned to classify the brachiopods and was appointed a paid assistant on 10 May 1852. During the summer he was in charge of surveys for the Semmering Tunnel and in the Mur Valley.
In 1853 Franz von Hauer undertook to make a geological profile across the Eastern Alps from Passau to Duino. Suess asked to be made responsible for the highest section, that of the Dachstein. With a guide he reached the summit, where he enjoyed a vast panorama which he compared with the countrysides around Vienna, Prague, and Carlsbad; the differences were puzzling, and he decided to devote himself to elucidation of this problem.
On 12 June 1855 Suess married Hermine Strauss, the niece of the director of the Museum of Natural History and the daughter of a prominent Viennese physician. Fearing that he would not be able to support a family, his father agreed to the marriage on the condition that his son work at the leather factory in the afternoon, while the mornings were devoted to the classification of brachiopods and alpine rocks. In 1856 Suess applied for the post of Privatdozent at the University of Vienna but, lacking the doctorate, he failed to qualify. At the recommendation of Haidinger, the minister of education circumvented this difficulty by naming Suess extraordinary professor of paleontology, thereby freeing him from work at the factory. He became full professor of geology five years later.
Looking back on his life, Suess realized that these youthful years had been decisive. The experiences and impressions determined the goals he was to pursue and the means by which he attained them. The outlook of the high bourgeoisie in a multinational empire favored intellectual life and research. A classical and technical education and the consciously exercised gift of presenting and explaining his ideas so as to make them comprehensible had prepared Suess for a manifold career. His knowledge of languages early brought him wide-ranging personal and literary associations. He made geological excursions with researchers from Switzerland (from 1854), France (from 1856), Germany (from 1856), England (from 1862), and Italy (from 1867). Suess thus had the opportunity to visit important regions in the company of those who had explored them, and to discuss his findings and make comparisons. At an advanced age he learned Russian in order to be able to consult the original literature.
Suess took an early interest in education, at first promoting the popular university (from 1855), and then studying conditions at all levels of the educational system. As a result of his work in education, Suess was elected to the Vienna city council (1863–1886), to the provincial diet (1869–1896), and to Parliament (1872–1896). He was even approached to become secretary of state for education, but he preferred to remain a professor of geology. His vast knowledge enabled him to study conditions in other countries, to compare them with those in the empire, and to propose solutions. Investigating the conditions of workers in Great Britain, he offered predictions about the future status of labor in Austria and attempted to prepare the way for change. His recommendations influenced the passage of social legislation and the appointment of labor inspectors (1873).
On 20 December 1857 the dismantling of the bastions and fortifications of the old city of Vienna was begun, to make way for new neighborhoods and official buildings. Using the exposures presented by the excavations, Suess studied the city’s subsoil and in 1862 published Der Boden der Stadt Wien.
Two difficult projects brought Suess great fame and the gratitude of his fellow citizens: the diversion of drinking water from the mountains to Vienna and the Danube Canal.
A great part of Vienna was supplied with water from wells. Epidemics, particularly of typhoid fever, were frequent and claimed numerous victims. In 1863 Suess was elected to the city council and was named head of a commission to study the water supply. Of fifty-three competing projects, Suess’s proposal, which was one of the boldest, was chosen: it called for bringing water from mountain springs by an aqueduct. Three reasons determined its selection: mountain regions received more precipitation than the plains, they were sparsely populated, and the water could flow by gravity. Suitable springs existed in the Alps only seventy miles from Vienna, and their owner was ready to sell them. After convincing the taxpayers and their representatives, it was necessary to plan and direct the construction of the aqueduct, which began operation on 17 October 1873. The number of deaths from typhoid fever subsequently dropped from 34 to 9 per 1,000.
The low-lying sections of Vienna were often flooded. In 1869 Suess was appointed to a commission for the control of the Danube; and although he was an educational inspector busily engaged in reorganizing public instruction, he accepted. In November of that year he was a member of a delegation accompanying the emperor to Egypt to attend the opening of the Suez Canal. Noting the relevance of the canal to his own project, Suess discussed the technical problems of dredging with the head of these operations. He hired this official to come to Vienna in 1870, with his crew and machinery, to excavate the bed of the Danube Canal. Many difficulties arose, some unpredictable, such as the variations in the river’s flow. On 15 April 1875 the canal was opened, and there have been no major floods in Vienna since 1876.
After the Universal Exposition of 1873 a chain of financial failures and misfortunes began. Suess attempted to clarify the phenomena by linking political, economic, and geological problems in a new fashion. He also studied the problems associated with gold (1877) and silver (1892). His book on silver, translated into English at the initiative of the United States government, was published in America.
Suess also played an important role in what is now called the politics of science. In 1860 he was named a corresponding member of the Imperial Academy and a full member in 1867; he was elected vice–oresident in 1893 and president in 1898. He resigned in 1911, having reorganized the Academy into a more effective body for scientific research. Skilled in obtaining funds for important projects, Suess arranged archaeological expeditions to Egypt and oceanographic cruises in the Mediterranean and the Red Sea. He organized the union of German–language academies that later became the Union Mondiale des Académies; and he was able to orient and direct their collaboration toward great common goals, such as the Thesaurus linguae latinae.
Suess likewise wielded great influence at the University of Vienna. He was occupied both with the organization of the curriculum and the location and construction of the new university. Although Suess was a Protestant, his election as rector was supported by the votes of the Catholic faculty. Yet the greater part of his political and technical activities gradually yielded to geology and teaching, and Suess declined very attractive offers in order to devote himself to what he considered his principal responsibility. After reaching retirement age, he gave all his time to his fundamental work.
Suess emphasized the joy derived from contact with nature, considering it a relic of the savage state that had passed through the filter of civilization. It is, he believed, only in nature that the geologist can grasp the scale of the mountains and can immerse himself in their disposition, that he learns to read the explanation of their structure and of its development.
Suess knew most of the European geologists of the older generation—that of Élie de Beaumont, Haidinger, and Escher–as well as those of his own and the following one. He often experienced the strength of scientific ties, even across political frontiers. His friendship with the Italian geologist Quintino Sella (who also was the first minister of finance of the kingdom of Italy) was based on their common views on both science and the conduct of affairs of state.
Each summer was dedicated to geological expeditions. In autumn Suess often participated in meetings and geological excursions with foreign colleagues in the Swiss Alps, Italy, and other countries. All his field excursions were carefully planned and formed part of a flexible research program. Success also emphasized that his work on cataloging the mineralogical collections and in the library of the Museum of Natural History had enabled him to become familiar with groups of fossil forms from different strata and with the literature. Indeed, his knowledge of the geological literature and his gift for locating information in obscure publications was highly impressive.
Suess began his scientific career as a paleontologist. Graptolites, brachiopods, ammonites, and the mammals of the Tertiary especially attracted his attention. He studied their anatomy and compared their modes of life with those of existing species, engaging in what is now called paleobiology. Emphasizing the unity of the living world, in 1875 he created the concept of the biosphere. Earlier, in 1860, Suess had attempted to use the Paleozoic brachiopods to determine the depth of water at the time of sedimentation. He enlarged the goals of Lyell’s stratigraphy by comparing series deposited in different regions, on forelands and in mountain chains, and by distinguishing epicontinental and geosynclinal series. Accordingly, his studies gradually shifted from stratigraphy to tectonics, of which he must be considered a creator.
Suess received no formal training in paleontology or geology. An autodidact, he increased his knowledge through contact with his seniors, friends, and students. In 1865 he was commissioned to write a treatise on the geology of the Austrian Empire, for which project he obtained a leave of absence and funds to travel. He undertook long tours on foot. The comparative method, so advantageous in anatomy, appeared of increasing importance to him. After observing asymmetry in the Carpathians, the Sudetes, and the Apennines, he located it again in the Alps. The initial result of these peregrinations was Die Entstehung der Alpen (1875), which contained many of his governing ideas in embryonic form. Rather than a geological description of the Alps, it was an overall view of the genesis and structure of mountain chains.
During this period the ideas of Leopold vor Buch and Élie de Beaumont still largely deter mined the image of mountain chains. For Buch eruptive rocks were the active elements in mountain chains; they raised the central zones and exerted lateral pressures against the two sides, there by causing folds and other dislocations. Élie de Beaumont determined the folds of various ages and made a first attempt at a global tectonics. Lack of information obliged him to make extrapolations, such as his proposed system of the pentagonal dodecahedron, the directions of which supposedly corresponded to the ages of the folds.
Suess accepted neither the idea of the raising of the central zone by crystalline rocks nor the notion of symmetry with respect to that zone. He distinguished a foreland and a hinterland, between which movements were tangential and unilateral. There were, in his view, no rectilinear directions, but only an ensemble of curved lines. The mountain chains formed garlands and festoons, and their convex side was usually directed toward the exterior. The curves and the disposition of the folds depended on the form of the foreland and on the resistance of the materials. The crystalline rocks of the central zones were passive.
One of the first tasks of the geologist was to trace the contours of the festoons and garlands and to ascertain their internal organization. A hierarchy of features was thus discerned, enabling him to grasp the geometric anatomy and to locate its details. Next he had to reconstruct the movements that had caused these structures, in order to visualize the youth, maturity, and old age of the chain.
This work marked the beginning of the extraordinary development of tectonics and made possible the work of Marcel Bertrand, Pierre Termier, Hans Schardt, Maurice Lugeon, and Emile Argand. The point was stressed by Bertrand in his preface to the French translation of Das Antlitz der Erde when he gave an example of this fruitfulness that has become classic. In 1846 Arnold Escher recognized the great extent of the Permian overthrust on the Tertiary of the Glarus Alps. His student and successor Albert Heim extended the study and in 1870 constructed the “Glarus double fold”(Glarner Doppelfalte), thrust from both north and south, a phenomenon that aroused a heated polemic throughout Europe and pitted the partisans of overthrusts against those who interpreted the phenomenon as a stratigraphic superposition. Basing his argument on the principle of asymmetry, Bertrand interpreted the ensemble as a single nappe with a root lying to the south and a head plunging toward the north, a view incorporated into Lugeon’s synthesis of the Northern Alps (1902). (This was the origin of the modern concept of the nappe or decke.)
Studies conducted in the Alps and in Calabria convinced Suess that earthquakes are manifestations of mountain chains in motion and are produced along great faults. Volcanoes and intrusions are only accessory phenomena, most often occurring at the interior of arcs.
The concept of the geosyncline, elaborated in the United States by James Hall and James Dana, had been introduced to Europe. Suess stressed not only the difference in thicknesses, but also the diverse evolution of the stratigraphic series of the forelands and of the folded and overthrust zones from the point of view of lithology and of the facies. This was the first rational classification of the features of terrestrial physiognomy and an attempt to interpret and synthesize them that Suess later took up in greater detail.
In 1883 Suess signed a publication contract for his masterpiece, Das Antlitz der Erde, scheduled to appear in three volumes. The first fascicle was published the same year, and the entire work was completed in 1909. Certain of the notions, principles, and ways of reasoning presented in the work have entered so profoundly into the thinking of geologists that many are unaware of their origin and consider them archetypes. It is therefore worth mentioning a few examples.
Suess avoided dogmatism in presenting his views. He sought to assimilate and coordinate a century of observations, attempting to extract order from chaos by means of several governing ideas. Field experience since his youth developed in Suess a profound grasp of the relations between major outlines and details, between the structures and the behavior of materials, and between assemblages of facies and their position in the whole. He thus was able to assimilate observations in the literature, most of which were made from different viewpoints. According to his contemporaries, Suess knew the literature better than any other scientist of his time and was familiar with sources that were difficult to obtain even in major libraries. The result was a three-dimensional picture on which he superposed changes through time.
Because Das Antlitz der Erde was the first presentation of global views of this type, it was necessary for Suess to create an appropriate language; and his book therefore contains a considerable number of new terms, many of which are still in use.
The principal value of the “great mosaic” method consists of its manner of observing, of representing, and of transmitting–in a language developed especially for the purpose–the ensemble that is the face of the earth, a multidimensional ensemble of forms and contours arranged hierarchically on different scales. The principal features emerged from a host of details, communicating the author’s enthusiasm to the reader. Enthusiasm for his discoveries did not, however, render Suess a prisoner of his ideas: over the years he reworked his syntheses and hypotheses. Some of the views presented in the first volumes are contradicted in the last, a circumstance Suess explained by invoking the image of a mountain climber: as an alpinist climbs from rock to rock, the scientist goes from error to error: and even if he does not reach the summit, at each stage his view encompasses more territory.
At the beginning and at the end of this masterpiece the entire earth revolves before the reader’s eye as Suess attempts to show its history by deciphering the features of its surface. He distinguished five ancient continents: Laurentia, Fennoscandia (a term created by Wilhelm Ramsay), Angaraland, Gondwanaland, and Antarctica. Between Eurasia and the Indo-African lands there extended a series of recently joined mountain chains that had originated in an ancient Mediterranean, called Tethys by Suess, extending from Central America to the Sunda Islands. These chains were generally concave toward the north in Asia and toward the south in Europe. Another series of mountain chains in festoons and garlands surrounded the Pacific Ocean. Suess distinguished three principal epochs of folding in Europe, evidence of which can be found in the more resistant rock massifs. Their age decreases as one goes from north to south. The most recent chains, bordering on the Mediterranean, are already subsiding. The ancient chains, eroded and covered by more recent deposits, can be reactivated and are therefore posthumous. Suess compared subsidences and giant grabens to tangential dislocations (folds and overthrusts), believing that subsidences characterize an important part of the surface of the earth.
The evolution of the concept of marine oscillations is an interesting example of the way in which Suess conceived a seminal idea, gathered observations to support it, followed its ramifications and weighed its consequences before proposing it, and finally, set it against the image of nature at the time.
In 1860 and 1861 Suess studied the littoral formation deposited by the Tertiary Mediterranean on the border of the Bohemian massif north of Vienna. Following these ancient shorelines, he speculated that the observed regularity of their elevations was due not to an uplift of the massif but to a lowering of the sea level. From then on, he gathered observations relevant to this subject. After his visit to the region of the Suez Canal in 1869, Suess asserted that the isthmus was the result not of an elevation but of a relatively recent lowering of the waters. He decided at that time to examine the vestiges of the similar shores of northern Norway but was not able to do so until the summer of 1885, when he made two trips to the interior from Tromsö. He described the countryside, including the solifluction phenomena, in minute detail. The stepped terraces on the flanks of the fjords and valleys strongly impressed him. Trusting his own eye and dispensing with leveling, Suess concluded that the terraces are horizontal and do not intersect. They indicate successively lower sea levels without elevation of the shield. Suess not only studied the terraces but also investigated the Scandinavian literature on the subject dating as far back as the eighteenth century.
From his conclusion that the ancient massifs have remained stable (єὐσтάσєια), Suess deduced that it was the level of the sea that had varied; as a result he proposed the principle of eustatic levels (Das Antlitz der Erde, II, 680). Theoretically, these levels should be found on the peripheries of all seas and oceans, with the exception of some interior seas, such as the Baltic. Suess probably would not have been as affirmative regarding the stability of the old shields had he leveled the traces of the ancient sea levels or had he taken into account the measurements of others.
He did, however, reflect for more than fifteen years on the consequences of this concept. In his view the changes in level resulted from deformations of the ocean floor:“The earth yields; the ocean follows”(ibid.) A multitude of phenomena, even the form of the continents, tapered toward the south and were connected to the stated principles. Sedimentary deposits in the seas displace the waters and cause them to rise, and major subsidences lower them. Suess traced the history of the great transgressions since the Silurian, concentrating especially on that of the Middle Cretaceous.“The history of the continents,”he wrote,“results from that of the seas”(II, 700). The virtual similarity of the great transgressions on all the continents would explain why the limits of the formations (recognized by William Smith and corresponding to interruptions of sedimentation) are found in so many localities.
In his attempt to learn more about the little-known sea floor Suess was forced to extrapolate from structures known on land. He distinguished the Atlantic coastal type from the Pacific, the former interrupting the structural lines and the latter being more or less parallel to them. Although Suess supposed that the great oceanic basins were formed by collapse between stable blocks, he was aware of the contradiction between the hypotheses of collapse and of contraction, and discussed the problem.
Volcanological studies led Suess to posit that oceanic waters result from the degasification of the earth (III , pt. 2, 631). He introduced the distinction between juvenile and vadose waters (III , pt. 2, p. 630). Juvenile gases and, higher in the earth’s crust, thermal waters not only displace and concentrate numerous chemical elements: they are also important in the transport of terrestrial heat. Juvenile gases, Suess thought, originate under the sialic crust, a term created to indicate that silicon and aluminum are the principal and characteristic elements of this terrestrial layer (III , pt. 2, 626). Under this first sphere would be that of sima (characterized by silicon and magnesium) and finally the barysphere or nife (nickel and iron), which is primarily metallic. Studies of abyssal rocks sometimes suggested the presence of a“crofesima”or“nicrofesima”(III, pt. 2, 627). Suess thought that juvenile gases also played a role in lunar volcanism (III, pt. 2, 689).
In a final chapter of Das Antlitz der Erde Suess discussed life and its distribution on the earth. The old shields provided refuge for the terrestrial faunas, sheltering them during marine transgressions. The history of communications between the ancient lands and of the invasions and exchanges of faunas constitutes an important chapter that completes the study of the formation of mountain chains and of marine transgressions.
The results of many later methods were not at Suess’s disposal for this synthesis, but those that did exist were employed to best advantage so that his work remains the structural model for such a project. His accomplishment is still more impressive when it is appreciated that one man was able to create such a panorama. Suess stressed several times that certain problems could be solved only by new techniques–for example, when he regretted the lack of methods for determining absolute ages (II, 703).
Such a critical analysis combined with a synthesis of broad compass strongly impressed his contemporaries and is reflected in the literature of the period. Marcel Bertrand wrote:“It would almost appear to us that he would be the most advanced in our science who has best understood this book. . . . It is not only a question of making known the origin of ideas that will have an important place in the history of our science; it is also a matter of bringing within the reach of a great number of readers an almost inexhaustible mine of documents, the primary material in every kind of research and new discoveries. At first readers have been struck by an initial flowering of ideas: others remain in embryo on the same pages.”Diverse and insular branches of the earth sciences were linked; and regional geologies were fitted into greater ensembles, thus forming new units that often transcended national frontiers.
The newly created field of structural geology was tied by many threads to stratigraphy–once the central concern of geology–and to geomorphology. Many paths of communication were opened toward the understanding of terrestrial substances and of their behavior, composition, origin, and evolution. Friedrich Becke, another Viennese professor, had developed links to petrography by defining the families of Atlantic and Pacific rocks and especially by creating the notion of zones of depth of metamorphism and the principle of diaphthoresis, thereby making it possible to grasp the upward motion of certain metamorphic rocks. Bruno Sander at Innsbruck and Schmidt at Leoben established relations between the deformations and fine structures of rocks and between internal displacement and mineralogical evolution.
In 1912 Alfred Wegener outlined in several lectures his new global kinematics and mobilism. As Bertrand had affirmed, Suess’s work was not an end, for it opened many paths toward new knowledge and explanations. The impetus given in different directions to Austrian science and to the international scientific community can still be detected in the greater part of the earth sciences.
I. Original. Works. Suess’s memoirs, Erinnerungen (Leipzig, 1916), discuss his family origins as well as his scientific and political activities to the age of sixty and offer valuable insight into the development of his concepts and the reasoning and motivation for his accomplishments.
His separately published works include Über das Wesen und den Nutzen palaeontologischer Studien (Vienna, 1857): Der Boden der Stadt Wien nach seiner Bildungsweise (Vienna, 1862); Die Entstehung der Alpen (Vienna, 1875): Die Zukunft des Goldes (Vienna, 1877); and Die Zukunft des Silbers (Vienna, 1892), translated into English as The Future of Silver (Washington, 1893).
Das Antliz der Erder 3 vols. (Prague–Vienna–Leipzig, 1883–1909), was translated into French as La face de la terre, 4 vols. (Paris, 1897–1918), and into English as The Face of the Earth 5 vols. (Oxford, 1904–1924).
The Royal Society Catalogue of Scientific Papers lists 81 memoirs published before 1900: V, 883–884: VIII, 1043–1044: XI 530: and XVIII, 1034. See also Poggendorff, III, 1313–1314; IV, 1464; and V 1230.
II. Secondary Literature Biographical studies of Suess include the notices by A. Geikie, in Nature, 72 (1905), 1–3; C. F. Parona, in Atti dell’ Accadmia delle scienze (Turin), 49 (1913–1914), 959–966; E. von Koerber, in Almanach der Akademie der Wissenschaften in Wien64 (1914), 349–362; N.Krebs, in Mitteilungen der Geographischen Geselleschaft in Wien, 57 (1914). 296–311;R.Michanle, in Zeitschrift der Deutschen geologischen geologischen Gesellschaft, 66 (1914) 260–264: and p.Termier, in Revue généreale des sciences pures et appliquées, 25 (1914), 546–552, translated into English in Smithsonian Annaul Report for 1914 (Washington, 1915), 709–718.
On his importance in the history of geology, see G. Sarton, “La synthèse géologque de 1775 à 1918,” in Isis, 2 (1914–1919), 381–392.
"Suess, Eduard." Complete Dictionary of Scientific Biography. . Encyclopedia.com. (July 24, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/suess-eduard-0
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"Suess, Eduard." A Dictionary of Earth Sciences. . Encyclopedia.com. (July 24, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/suess-eduard
"Suess, Eduard." A Dictionary of Earth Sciences. . Retrieved July 24, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/suess-eduard
Eduard Suess (ā´dōōärt züs), 1831–1914, Austrian geologist, b. London. He was a professor (1857–1901) at the Univ. of Vienna and served for more than 20 years in the Austrian parliament. He was an authority on structural geology, especially of mountains, and postulated the existence of the giant land mass Gondwanaland (see continental drift). His great work was Das Antlitz der Erde (5 vol., 1883–1901; tr. The Face of the Earth, 1904–24).
"Suess, Eduard." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (July 24, 2017). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/suess-eduard
"Suess, Eduard." The Columbia Encyclopedia, 6th ed.. . Retrieved July 24, 2017 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/suess-eduard