Targioni Tozzetti, Giovanni

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(b. Florence, Italy, 11 September 1712; d. Florence, 7 January 1783)

natural history.

Targioni’s father, Benedetto, was a doctor; his mother, Cecilia, was the daughter of Gerolamo Tozzetti, a jurist. He added her maiden name to his paternal surname, Targioni. In 1734 Targioni Tozzetti received his degree in medicine at Pisa; for the rest of his life he practiced medicine in Florence, where, among other things, he promoted prophylactic inoculation against smallpox. In 1739 he was appointed director of the Magliabechi Library, a position which required his cataloging thousands of books and manuscripts. Targioni Tozzetti was strongly inclined toward natural history. His father, a passionate student of botany, understood and appreciated this interest, and encouraged it by entrusting his son, in 1731, to the botanist Pier Antonio Micheli. For six years Targioni Tozzetti was Micheli’s shadow, the latter’s pleasure in teaching being matched by the former’s in learning. After Micheli’s death in 1737 Targioni Tozzetti was deemed worthy to be director of Florence’s botanical garden and to teach botany.

A scientific journey from Florence to Cortona, with Micheli in 1732, served to emphasize Targioni Tozzetti’s true vocation, that of traveling naturalist. Long journeys undertaken between 1742 and 1745 enabled him to observe natural phenomena and the ancient monuments of considerable sections of Tuscany. The harvest gathered in the field of natural science was truly outstanding, encompassing the three kingdoms of nature.

In his study on the relations between normal hydrography and landform, Targioni Tozzetti made wide-reaching synthetic observations, starting with the most minute analytic observations. Some of the major scientists of his time believed that the erosive action of currents, even though increased by time, was entirely insufficient to account for wide valleys and deep gorges. Assuming a decisive position against the most famous of them all, Buffon, who believed it essential in explaining these phenomena to posit the action of marine currents prior to the emergence of land, Targioni Tozzetti maintained that all the valleys and gorges he had observed were the result of erosion caused by currents. He also noted the enormous quantity of materials altered by the waters themselves in the course of time. On the basis of these observations Targioni Tozzetti was able to outline, for the first time in the history of science, the morphological evolution of certain landscapes, such as that of the hills of the Tuscan ante-Apennines, formed by Pliocene marine sediments. Going back to “very remote times, unknown to us,” Targioni Tozzetti said that the hills appeared to have been formed by current-caused erosion on the marine platform that emerged after the sea had receded. He reconstructed the movement of this platform by identifying it with the plane that connects the summits of the existing hills. Considering the future, he stated that these hills would also be “broken up and destroyed” by erosion.

Targioni Tozzetti’s interest was also aroused by the disappearance of early Pleistocene lakes, where we find today the characteristic intermountain basins of the Apennines. In the Upper Valdarno he demonstrated the existence of a large lake in antiquity; he then studied the disappearance of the waters as a result of the complete alluvial refilling of the basin. Last, he investigated the regressive erosion that the waters cause on the lacustrine deposits. He also explained with great clarity the origin of the gorges in the wide Arno Valley by the presence of very hard rocky masses which were buried by the lacustrine sediments lacking cohesion. It is in these sediments that one not infrequently finds the bones of elephants and other large mammals. Targioni Tozzetti demonstrated that these fossils are not the remains of elephants that accompanied Hannibal’s army during the Second Punic War, as scholars of the period believed: rather, they were a part of the fauna of Tuscany before the appearance of man in the region.

Throughout his life Targioni Tozzetti hoped to write a full description of Tuscany from both the general synthetic and the regional analytic points of view. The work was never carried out: but his Prodronlo, published in 1754, is of great interest, for it outlines in minute detail the plan of his work-a plan amazing for the modernity of its conception. The general description would have been developed in much the same manner as would be used today: examination of the relief, hydrography, climate, flora, fauna, and finally human manifestations. Targioni Tozzetti’s great understanding of the relations between nature and man extended to such diverse topics as the changes introduced by man in the courses of rivers or at their mouths: the changes in malarial marshlands (a very important economic and social problem in Tuscany in the eighteenth century): the location of population centers in relation to relief or to water: the construction of roads or ports: and the better exploitation by man of all the natural resources. In brief, he saw man as an indefatigable and efficient modifier of terrestrial surfaces: “It would not be useless to consider Tuscany as it indeed was before it was inhabited my man...to understand the great changes that have followed successively from industry and later from human negligence.” Today Targioni Tozzetti is recognized as one of the precursors of modern human geography.

Targioni Tozzetti was unable to devote much time to scientific research, since he was fully occupied with his duties as a physician and a librarian. He himself felt “condemned to waste his life in studies opposed to his inclination.” But the results he achieved, even though limited, justify his being considered, after Lazzaro Spallanzani, as the most active Italian naturalist of the eighteenth century. His scientific passion was transmitted to later generations: his son Ottaviano, his nephew Antonio, and his grandnephew Adolfo were doctors and naturalists of note.


I. Original Works. Targioni Tozzetti’s writings include Relazione d’alcuni viaggi fatti in diverse parti della Toscana, per osservare le produzioni naturali, e gli antichi monumenti di essa, 6 vols. (Florence, 1751–1754; 2nd ed., 12 vols., 1768–1779): Prodromo della corografia e dellatopografia fisica della Toscana (Florence, 1754), and two works valuable for the history of science, which he was one of the first to cultivate. Notizie sugli aggrandimenti delle scienze fisiche accaduti in Toscana nel corso di anni LX del secolo XVII (Florence, 1780), and Notizie della vita e delle opere di Pier’ Antonio Micheli (Florence, 1858). Some of his more interesting scientific material is in the anthology of F. Rodolico, La Toscana descritta dai naturalisti del settecento (Florence, 1945), passim.

II. Secondary Literature. Biographical and bibliographical information is in Novelle letterarie, 14 (1783), col. 97. On Targioni Tozzetti’s work, see the following (listed chronologically): O. Marinelli, “Giovanni Targioni Tozzetti e la illustrazione geografica della Toscana;” in Rivista geografica italiana, 11 (1904), 1–12, 136–145, 226–236; R. Concari, “La geografia umana nei ‘Viaggi’ di Giovanni Targioni Tozzetti,” ibid. , 41 (1934), 28–41; and F. Rodolico, “La collezione mineralogica di Giovanni Targioni Tozzetti,” in Catalogo del Museo di storia della scienza (Florence, 1954), 274–280: and “Lo studio ‘fisico’ della città di Firenze impostato da Giovanni Targioni Tozzetti nel 1754,” in Rivista geografica italiana, 64 (1967), 110–113. A detailed description of his journeys, accompanied by itinerary maps, is in F. Rodolico, L’esplorazione naturalistica dell’Appennino (Florence, 1963), 133–137, 152–160, 366–369.

Francesco Rodolico