Issel, Arturo

(b. Genoa, Italy, 11 April 1842; d. Genoa, 27 November 1922)

geology.

Issel was the son of Raffaele and Elisa Sonsino Issel. He studied under Giuseppe Meneghini and graduated with a degree in natural science from the University of Pisa in 1863. From 1866 to 1917, he taught geology, mineralogy, paleontology, and geography at Genoa. Issel was a skillful geologist, but the most characteristic aspect of his talent was the versatility that enabled him to work in an astonishing variety of fields. Based on a solid foundation of learning and far from being any sort of dilettantism, this versatility was particularly oriented toward the study of living mollusks, a field in which Issel soon became a master, and ethnology, especially the then emerging paleethnology.

Issel belonged to that elite group of traveling Italian naturalists who, in the second half of the nineteenth century, contributed much to the scientific knowledge of distant regions, especially of Africa. In 1865 he traversed a considerable portion of the coast and the island of the Red Sea, collecting living and fossil mollusks, both on the present shores and in the sediments deposited since Miocene times. Thus, he simultaneously carried out zoology nad paleontological researches, which are presented in the excellent Malacologia del Mar Rosso (1869), in which 804 species, eighyy-five of them previously unknown, are described and discussed in relation to the fauna of the neighboring seas. Also worthy of mention are Issel’s minor contributions to the malacology of Italy and of regions outside Europe (including Tunisia, Peria, and Borneo). He returned to the coast of the Red Sea in 1870, also making an expedition to Cheren in the Ethiopian highlands. Shortly thereafter he published a lively diary entitled Viaggio nel Mar Rosso e ter i Bogos (1872). He reflected at length on his geological observations of the two voyages, and not until almost thirty years later did he issue his valuable paleogeographic study “Essai sur l’origine et la formation de la Mer Rouge”(1899).

Much of Issel’s research concerns the recent geological events of the Mediterranean basin, which he traversed from the Greek archipelago to Malta, from the Ligurian coast to the Tunisian coast. He contributed to the geological study of Malta, Zante, and Galite (Jezīret Jālita); he established a geological stage of the Pleistocene marine series, the Tyrrhenian, which followed the Calabrian and the Sicilian; he devoted particular attention to the valleys which, in Liguria, continue below sea level. This last subject is related to Issel’s research on the slow oscillations of the ground, for which he proposed the name “bradyseisms.” Collecting and synthesizing not only his own observations made along the shores of the Red Sea and the Mediterranean but also those made previously by other investigators, he wrote the now classic “Le oscillazioni lente del suolo o bradisismi”(1883). The criteria set forth there were further used in the detection and exact determination of bradyseisms on the shore. Issel also concerned himself with the present-day conditions in the Mediterranean through the study of samples from its bottom.

Born and raised in Liguria, Issel devoted much time to the study of this region, which is small but very interesting from a naturalist’s point of view. In addition to geologic surveys made in collaboration with L. Mazzuoli and D. Zaccagna, he made dozens of contributions in geography, seismology, geology, petrography, paleethnology, and paleontology, which were collected in two large volumes: Liguria geologica e preistorica (1892). The title of this work invites closer consideration of the science of paleethnology, in which Issel was already interested at the age of twenty; in fact, there are two articles, dated 1864 and 1866, devoted to the ossiferous caverns which he visited near Finale (Liguria) and on Malta. Throughout his life he conducted fruitful research on the remains of prehistoric man in Liguria, maintaining close contact with the famous paleethnologist L. Pigorini, on whose Bullettino di paletnologia italiana he collaborated. The 1892 analytical work was followed by the synthetic “Liguria preistorica” (1908). He also conducted some more purely ethnological investigations, studying African (Bogos, Niam Niam) and Burmese populations.

BIBLIOGRAPHY

I. Original Works. Issel’s writings include Malacologia del Mar Rosso: Ricerche zoologiche e paleontologiche (Pisa, 1869); Viaggio nel Mar Rosso e tra i Bogos (Milan, 1872);“Le oscillazioni lente del suolo o bradisismi: saggio di geologia storica,” in Atti della R. Universita di Genova, 5 (1883), 1-422; Liguria geologica e preistorica, 2 vols. (Genoa, 1892); “Essai sur l’origine et la formation de la Mer Rouge,” in Bulletin de la Société belge de géologie, de paléntologie et d’hydrologie, 13 (1899), 65-84; and “Liguria preistorica,” in Atti della Societa ligure di storia patria, 30 (1908), 1-775.

II. Secondary Litrature. Biographical and bibliographical notes are M. Canavari, “Commemorazione di Arturo Issel,” in Memorie dell’ Accademia dei Lincei, classe di scienze fisiche, matematiche e naturali, 5th ser., 14 (1923), 679-697, with complete bibliography; P. Principi, “Arturo Issel,” in Bollettion della Societâ geologica italiana, 42 (1923), xx-xxiv; and F. Sacco, “Arturo Issel,” in Bollettion del R. Ufficio geologic, 49 (1922-1923), 1-25. On Issel’s voyages, see F. Rodolico, Naturalisti esploratori dell’Ottocento italiano (Florence, 1967), pp. 151-1071, with selections from Issel’s work.

Francesco Prodolico