POURTALèS, LOUIS FRANçOIS DE

(b.. Neuchâtel, Switzerland, 4 March 1823 or 1824; d. Beverly Farms, near Salem, Massachusetts, 17 or 18 July 1880)

oceanography.

One of Louis Agassiz’s favorite students, Pourtalès joined his master’s “scientific factory” in Neuchâtel about the age of fifteen. He came to the United States in 1847 when Agassiz resettled there, and he prepared most of the illustrations for Agassiz and A. A. Gould’s Principles of Zoology (Boston, 1848). Pourtalès joined the U.S. Coast Survey in 1848, and he served as assistant under three superintendents, making use of his education as an engineer by surveying and by heading the tidal division after 1854. The death of his father about 1870 brought Pourtalès the title of count and financial independence. He resigned from the Coast Survey and returned to Massachusetts in 1873.

In his choice of a successor to direct the Museum of Comparative Zoology that he had founded at Harvard, Agassiz vacillated between Pourtalès and his Son Alexander. After his death, Pourtalès became “keeper” and Alexander Agassiz, “curator.” Between them they presided over one of the world’s greatest museums of natural history, with Pourtalès responsible for much of the administrative work from 1873 until his brief, final illness in 1880. On his frequent trips home to Switzerland, Pourtalès often visited England, where he was well known among naturalists for his deep-sea work. Pourtalès was exceptionally modest and unassuming. He married Elise Bachmann of Boston: the couple had one daughter.

Pourtalès was a pioneer in two fields where America was abreast of Europe: marine biology and submarine geology. Upon taking over the Coast Survey in 1844, Bache turned it from hydrography to oceanography by insisting on the preservation of the specimens brought up by the sounding lead. Because the lead brought up only small samples of the bottom, the first fruits of Bache’s new policy came in the study of sediments. Using the microscope, J. W. Bailey of West Point characterized the sediments obtained from Coast Survey vessels. When Bailey died in 1857, Pourtalès, who had earlier studied the foraminifera, inherited the entire work. The chart that he prepared in 1870, from nine thousand samples, showed the distribution of bottom sediments along the coast between Cape Cod and Florida. Pourtalès demonstrated that glaciers had extended offshore as far south as New Jersey, and his results have not been greatly improved upon by the research of the 1960’s.

In addition to studying sediments, Pourtalès collected whatever marine fauna he could find, especially corals. At Bache’s invitation, Louis Agassiz had begun collecting in 1847 from Coast Survey vessels in shallow water off Massachusetts. In 1851 Agassiz accompanied Pourtalès on a Coast Survey party to the Florida reefs, where Pourtalès collected sipunculidsand holothurians, on which he later reported. With this background in shallow-water forms, Pourtalès was ready to extend his researches into deeper water when after the Civil War the Coast Survey resumed operations under Louis Agassiz’s close friend Benjamin Peirce. In the steamers Corwin (1867) and Bibb (1868, 1869), Pourtalès extended the technology of dredging, hitherto confined to shallow water, to depths as great as 850 fathoms off the east coast of Florida. These pioneering dredgings—slightly earlier in time although not as deep as those of W. B. Carpenter and C. W. Thomson in Britain—led to the “opening of a new era in zoological and geological research”(L. Agassiz, Report of the Superintendent of the U. S. Coast Survey for 1869, Appendix 10 [Washington, D.C., 1872], 208). Accompanied by Louis Agassiz on the last of these three cruises, Pourtalès based his most distinguished work, Deep-Sea Corals (1871), on the collections he had made. He also specialized among the coelenterates in halcyonarians and among the echinoderms in crinoids and holothurians.

Like his colleagues on both sides of the Atlantic, Pourtalès was astonished by the abundance of living forms at depths previously believed to be largely uninhabited. He eagerly joined the planning for what was to be the great American dredging expedition: the cruise of the new Coast Survey steamer Hassler westward around South America. Louis Agassiz led the 1871-1872 expedition, with Pourtalès in charge of dredging. Although Hassler’s cruise failed—because of faulty equipment—to achieve its hoped-for results, it inspired Carpenter to promote in Great Britain the far more successful Challenger Expedition (1872-1876). Pourtalès’ researches, left unfinished at his death, are commemorated in the Pourtalès Plateau, an area off southeast Florida rich in corals, and the sea urchin Pourtalèsia, named in 1869 by Alexander Agassiz and found by H.M.S. Challenger to be one of nature’s most widely distributed genera. Pourtalès was a member of the National Academy of Sciences and the American Academy of Arts and Sciences.

BIBLIOGRAPHY

I. Original Works. A list of Pourtalès’ major publications appears in the longer version of the obituary notice by Alexander Agassiz, cited below. The two most important works are Deep-Sea Corals (Cambridge, 1871) and “Der Boden des Golfstroms und der Atlantischen Kuste Nord Amerika’s in A. Petermanns Mitteilungen aus J. Perthes geographische Anstalt, 11 (1870), of which an English version, without the essential colored charts, was published as Report of the Superintendent of the U. S. Coast Survey for 1869, app. 11 (Washington, D.C., 1872). Publications other than those listed by Agassiz may be found in Coast Survey Reports (1853-1872) and in Bulletin of the Museum of Comparative Zoology at Harvard College. Pourtalès’ correspondence is among the Coast Survey records in the U. S, National Archives and in the Museum of Comparative Zoology.

II. Secondary Literature. Contemporary obituaries are Alexander Agassiz, Proceedings of the American Academy of Arts and Sciences, 16 (1881), 435-443; and National Academy of Sciences, Biographical Memoirs, V (Washington, D.C., 1905), 79-89, of which a shorter version is in American Journal of Science, 3rd ser., 20 (1880). 253 255; and Nature, 22 (1880), 371-372. Agassiz gives Penmates’ birth date as 1824; his assistant H. L. Clark, in Dictionary of American Biography, gives 1823. See also Theodore Lyman, in Proceedings of the Boston Society of Natural History, 21 (1880), 47-48; Henry N. Moseley. in Nature, 22 (1880), 322-323; and P. Martin Duncan, in Natim, 22 (1880), 337.

Modern evaluations of Pourtalès’ achievements are Thomas J. M. Schopf, Atlantic Continental Shelf and Slope of the United States—Nineteenth Century, U.S. Geological Survey Professional Paper 529-F (Washington, D.C., 1968); and Rudolf S. and Amelie H. Schcltema, “Deep-Sea Biological Studies in America, 1846 to 1872—Their Contribution to the Challenger Expedition” in Proceedings of the Royal Society of Edinburgh,B ser., 72 (1971-1972), 133-144; these achievements are set in a wider historical context in Susan B. Schlee, The Edge of an Unfamiliar World. A History of Oceanography(New York, 1973), chs. 1–3.

Harold L. Burstyn