(b. Salins, France, 20 April 1824; d. Cambridge, Massachusetts, 17 April 1898)
geology, paleontology, topography.
Marcou was born in the Jura, and the natural history of the area had much to do with determining the course of his work in science. Educated in his native Salins and the lycée at Besançon, Marcou went to Paris to study at the Collége Saint-Louis. III health caused an interruption in his education, and after returning to Salins he began to explore the geology and paleontology of his native Jura. Marcou’s first published work was in mathematics, but his growing knowledge of natural history had become so extensive that by 1845 he was able to publish a highly original analysis of Jurassic fossils (“Recherches géologiques sur le Jura Salionis”) in the Mémories de la Société d’historie naturalle de Neuchâtel. Louis Agassiz, editor of the journal, was impressed by the yiung man’s grasp of a complex subject. The Swiss paleontologist encouraged the young man to do further work in the field, an ambition buttressed by Marcou’s appointment as professor of mineralogy at the Sorbonne in 1846 and curator of fossil conchology at the Jardin des plantes in 1847. With the support of Agassiz, in 1848 Marcou was awarded a traveling fellowship under the auspices of the Jardin des Plantes. He chose to spend this time under the guidance of Agassiz, who had gone to the United States. Thus in a short time, Marcou had established himself as a rising figure in geology and paleontology.
Marcou’s outstanding contributions were in stratigraphical geology and geological mapping, most notably a “Geological Map of the World” published in two European editions in 1862 and in 1875, a work one biographer classified as “the point of departure for all subsequent maps of this class.” The majority of his more than 180 publications—books, collections of maps, and articles—were French.
In 1850 Marcou married Jane Belknap, daughter of the historian Jeremy Belknap, and this association with New England lineage and wealth made him independent of material concerns, and he was able to carry on exploration and publish his findings. Marcou did not consider America or its scientist in the light of any permanent physical ort intellectual association. After exploring Lake Superior with Agassiz during 1848–1849, he returned to Europe in 1850. He came to the United States again in 1853 as an explorer of the trans-Mississippi West but left the fellowing year. He remained in Europe, Chiefly as a professor at the École Polytechnique of Zurich, until 1859, when he returned and teaching activities of tge newly established Museum of Comparative Zoology at Harvard College. After 1864 he returned to France on several occasions but considered Cambridge. Massachusetts, his primary residence. Marcou was physically prepossessing and intellectually dogmatic, with a high opinion of his own abilities—which were significant in areas other than science. His Derivation of the Name America (Washington, 1890) remains a highly original piece of scholarship, and his two-volume study of the life of Agassiz was a particularly modern appraisal for its time, especially for its dispassionate presentation of Agassiz’s scientific work. In 1867 Marcou was awarded the grand cross of the Legion of Honor, and in 1875 he undertook his last scientific exploration, in the employ of the United States Geographical Surveys West of the One Hundredth Meridian, wherein he did original work in the topography and stratigraphy of southern California.
Marcou did not support the theory of organic evolution. Three years before his death he wrote that Charles Darwin had “failed to give a doctrine well based and acceptable,” insisting that natural history progressed through reliance on new facts rather than hypotheses and theories.
This position was in some contrast to Marcou’s career in American science. As a field geologist, his experience was limited. Nevertheless, beginning in 1853 he became a party to a series of controversies that demonstrated his disdain for the work of Americans, and at the same time were a witness to the rise of modern American geology. Marcou’s role in these disputes took the form of insistence on the correctness of his identification of American stratigraphic topology. This certainty was grounded on little direct knowledge or experience, a condition that infuriated men of the caliber of William P. Blake, James Dwight Dana, James Hall, and William Barton Rogers, who were establishing the character of American professional geology. Early in his American career, Marcou stoutly defended the veracity and general utility of Ebenezer Emmons’ so-called Taconic system of New York stratigraphy, pitting himself against Dana and Hall in a matter not fully resolved for nearly fifty years. The Geology of North America (Zurich, 1858) contained an entire chapter castigating the scientific work and methods of Blake, Hall, and Dana, as well as “criticisms of the American Journal of Science and Arts,” Marcous’s controversies with American geologists of established reputation were epitomized in his attack on John Wesley powell and the research orientation of the United States Geological Survey in his The Geological Map of the United States and the United Stated Geological Survey (Cambridge, Mass., 1892).
In 1853 Agassiz’s influence had gained Marcou a position as geologist with the United States Army Topographical Corps surveying a Pacific railroad route along the thirty-fifth parallel. Marcou’s field experience, extending from Arkansas into California, was sufficient to embolden him to publish a geological map of the United States. This map (published in enlarged editions in 1855 and 1858) was an epitome of the argumentations surrounding the professionalization of American geology. The 1858 edition was especially offensive to American naturalists. Each edition of the map was criticized first by Hall, then by Blake, and finally by Dana, and each condemnation was met by Marcou with greater insistence on his veracity. The points at issue were matters of stratigraphic identification. Marcou was criticized for identifying large portions of the United States as belonging to the jurassic and Triassic periods, rather than the conventional Cretaceous classification. The matter was made even less agreeable by Marcou’s retention of important fossil evidence which belonged to the government; and upon its ultimate return, it was plain that these materials were of European rather than American Jurassic origin. Marcou had identified large portions of the continent as belonging to a period younger than the Jurassic, and, in the view of men such as Blake, all such analyses had been done without benefit of field experience and were of little service to American geology.
Subsequent investigations demonstrated that Marcou was at least partially correct in his nonempirical support of the Taconic system and his definition of the American Jurassic. It is significant that this European geologist, working in the tradition of Georges Cuvier, Jules Thurmann, and Agassiz, was consistent with an earlier period of universalist ambitions to define natural history. It is also noteworthy that his critics demonstrated, by the nature of their disputation, that it was impossible, on the basis of limited knowledge, to construct an American geological map of sufficient detail. By the late 1880’s, the work of the early railroad surveys and post-Civil War government geographical and geological efforts had made such contributions possible. Marcou’s independence was not unusual in the annals of other aspects of American natural history.
Marcou, whose career began as a promising fieldworker, was at his best as a teacher and descriptive stratigraphic geologist whose observations stimulated Americans to be more critical of their physical history. In this respect, his work served an important purpose in that it helped persuade both Americans and Europeans of the need for careful, comparative research methods and publications.
I. Original Works. A bibliography of Marcou’s publications in invertebrate paleontology is in John Belknap Marcou, “Bibliography of Publications Relating to the Collection of Fossil Invertebrates in the United States National Museum,” Bulletin. United States National Museum, no. 30 (Washington, 1885–1886), 241–244. Marcou’s works published in the United States are listed in Max Meisel, A Bibliography of American Natural History, 3 vols. (New York, 1924–1929), II-III.
Among his significant works are A Geological Map of the United States and the British Provinces of North America… (Boston, 1853); Carte géologique des États Unis… (Paris, 1855); Geology of North America… (Zurich, 1858): Letter to M. Joachim Barrande on the Taconic Rocks of Vermont and Canada (Cambridge, Mass., 1862); Carte géologique de la terre (Zurich, 1875); American Geological Classification and Nomenclature (Cambridge, Mass., 1888); and Life, Letters and Works of Louis Agassiz, 2 vols. (New York-London, 1895).
II. Secondary Literature. Alpheus Hyatt, “Jules Marcou,” in Proceedings of the American Academy of Arts and Sciences,34 (1899), 651–656; Hubert Lyman Clark, “Marcou, Jules,” in Dictionary of American Biography; William Goetzmann, Army Exploration in the American West:1803–1863 (New Haven, 1959), Passim; Edward Lurie, Louis Agassiz: A Life in Science (Chicago, 1960), passim; George P. Merrill, The First One Hundred Years of American Geology (New Haven, 1924), passim.