(b. Liège, Belgium, 4 February 1891; d. Lausanne, Switzerland, 16 July 1949)
Gagnebin was the eleventh of the twelve children of Henri Gagnebin, a minister, and the former Adolphine Heshuysen. In 1892 the family moved to Switzerland, where the father was pastor of the Free Church (Église Libre) in Biel and, from 1899, in Lausanne. Gagnebin attended the classical Gymnasium in Lausanne and took the bachelier ès lettres when he was eighteen; he then attended the University of Lausanne, where the program in natural sciences did not sufficiently engage his critical spirit and high intelligence. He became a member of the Société des Belles Lettres, a merry group of student revolutionaries.
In 1912 Gagnebin earned the licence in natural and physical sciences and became assistant to Maurice Lugeon, a specialist in the tectonics of Switzerland and one of the first advocates of the nappe theory of the Alps. He began geological researches toward his doctorate in 1913; they dealt with the Préalpes Bordières and the region of Ch′âtel St. Denis, famous for its wealth of fossils. (The Préalpes, or fore-Alps, are divided into a northwest front, the Préalpes Bordières; a distinct central zone, the Préalpes Médianes; and a southeast Zone des Cols, or Préalpes Internes.) He received the doctorate at the University of Lausanne on 5 July 1920 with a dissertation (published in 1924) which he modestly entitled Communication préliminaire. In this Communication, Gagnebin set forth the main features of the stratigraphy and tectonics of the Préalpes Bordières, including the northward movement of the Ultrahelvetian nappes and klippes into the region. He continued to study this region during the next few years while furthering his professional knowledge by working under Wilfrid Kilian at Grenoble (1920) and Émile Haug at Paris (1921).
Gagnebin began his academic career in 1917, when he occasionally replaced Lugeon as lecturer in paleontology; he was officially assigned to this post in 1928. He was promoted to associate professor in 1933 and delivered an inaugural lecture, “La durée des temps géologiques,” on 16 May of that year. In 1940 he succeeded Lugeon as full professor.
As a field geologist Gagnebin had made his mark as early as 1922 when he published his Carte géologique des Préalpes entre Montreux et le Moléson et du Mt.-Pèlerin. On the basis of this work the Swiss Geological Commission entrusted him with preparing the map of St. Maurice, a project that occupied Gagnebin’s summers from 1925 to 1933 and was published in 1934. From 1931 he was also a member of the Service de la Carte Géologique de France.
In 1939 Gagnebin published his observations on the shredding of the Simme nappe in the Chablais Préalpes. In 1941, with Lugeon, he brought out the classic investigation “Observations et vues nouvelles sur la géologie des Préalpes romandes.” In this study Gagnebin and Lugeon proposed continental drift as the primary process in the formation of the Alps; gravity then caused the resulting accumulation of faulting and nappes to slide into their present positions. (The gravity sliding hypothesis had earlier been advanced by Lugeon and Hans Schardt and had received new attention through the work of Daniel Schneegans in 1938.) Gagnebin extended this hypothesis to the Helvetic Alps of eastern Switzerland in 1945.
Gagnebin’s other publications include a few short communications on chance paleontological finds and two popular works, Le transformisme et l’origine de l’homme (1943) and Histoire de la terre et des êtres vivants (1946). A study of the Quaternary led him to the concerns of the earlier book; in it he demonstrated man’s descent from a branch of the anthropoids and stated the hope that man is still evolving and that “a different and more developed race will succeed ours.” The success of this book encouraged him to write the Histoire, in the final chapter of which he formulated a finalistic ethics—“Good is that which goes in the direction of life . . .”—and called for a new Aquinas to create “a metaphysics and a religious doctrine capable of integrating the sum of truths of which man has become aware in the last three or four centuries. . . .”
Gagnebin was in addition an ardent champion of modern music. With his friend the Vaudois writer C. F. Ramuz, the composer Igor Stravinsky, and the conductor Ernest Ansermet, he created the drama L’histoire du soldat (1918), in which he took the role of the narrator.
Gagnebin’s most important works are Carte géologique des Préalpes entre Montreux et le Moléson et du Mt.-Pèlerin, carte spéciale no. 99, Matériaux pour la Carte de la Suisse (Bern, 1922); “Description géologique des Préalpes bordières entre Montreux et Semsales,” in Mémoires de la Société vaudoise des sciences naturelles, 2, no. 1 (1924), 1–70, diss.; “La finalité dans les sciences biologiques,” in Revue de théologie et de philosophic, no. 78 (1931), 1–38; “St.-Maurice,” map. no. 8 in Atles géologique de la Suisse au 1:25,000 (Bern, 1934), written with F. de Loys, M. Reinhard, M. Lugeon, N. Oulianoff, W. Hotz, and E. Poldini; “La durée des temps géologiques,” in Bulletin de la Société vaudoise des sciences naturelles, 58 (1934), 125–146; “Notice explicative de la feuille St.-Maurice,” in Atlas géologique de la Suisse au 1:25,000 (1934), pp. 1–6: “Ossements de mammouth trouves dans la moraine de Renens, près de Lausanne, et recensement des restes de mammouths connus dans la région lémanique,” in Bulletin de la Société vaudoise des sciences naturelles, 58 (1935), 385–391; “Mécanisme ou vitalisme en biologie?” in Revue de théologie et de philosophie, no. 100 (1936), 1–7; “Découverte d’un lambeau de la nappe de la Simme dans les Préalpes du Chablais,” in Comptes rendus hebdomadaires des séances de l’Académie des sciences, 208 (1939), 822; “Découverte d’une nouvelle défense de mammouth dans la terrasse du Boiron, près de Morges, et précisions sur quelques restes de mammouths de la région lémanique,” in Bulletin de la Société vaudoise des sciences naturelles, 61 (1940), 291–296; “Observations et vues nouvelles sur la géologie des Préalpes romandes,” in Mémoires de la Société vaudoise des sciences naturelles, 7, no. 1 (1941), 1–90, written with M. Lugeon: Le transformisme et l’origine de l’homme (Lausanne, 1943: 2nd ed., 1947); “Queleques problèmes de la tectonique d’écoulement en Suisse orientale,” in Bulletin de la Société vaudoise des sciences naturelles, 62 (1945), 476–494; Histoire de la terre et des êtres vivants, no. 10 in the series Gai Savoir (Lausanne, 1946); and “La notion d’espèce en biologie,” in Dialectica, 1, no. 3 (1947), 229–242.
An excellent appreciation is Maurice Lugeon, “E. Gagnebin, 1891–1949,” in Verhandlungen der Schweizerischen naturforschenden Gesellschaft (1949), 382–399, with portrait.