Faujas De Saint-Fond, Barthélemy

(b Montélimar, Dauphiné, France, 17 May 1741; d. Saint-Fond, Dauphiné, 18 July 1819)

geology.

Faujas (who took his full name from the family estate at Saint-Fond in Dauphiné) was for some years a successful lawyer but, possessed by an overwhelming passion for natural history and coming under the influence of Buffon, he abandoned his legal career and was appointed assistant naturalist at the Museum d’Histoire Naturelle in Paris in 1778. In 1785 he became royal commissioner of mines and in 1793 was made professor of geology at the museum, a post he held until his death.

Faujas was a wide-ranging naturalist, as was common in his day. His most continuous and concentrated attention was given to rocks, minerals, and fossils (i.e., to geology, a name adopted in the late 1770’s), but he was also a physicist and a chemist. He applied his discoveries and investigations to practical affairs: for instance, in 1775 he found, analyzed, and opened up a deposit of a volcanic tuff similar to the Italian pozzolana, which was used industrially in France in the making of cement; he also wrote treatises on the construction and navigation of balloons, a practical scientific activity fashionable at that time.

The existence of a group of old volcanoes in central France had been ascertained by Guattard in 1752 through observations begun at Montélimar itself, but Guettard wrote later that basalt, with its prevalent columnar structure, was a crystallization from water. In the 1760’s Desmarest found the true explanation (not published until 1774): this basalt was of volcanic origin. Meanwhile, Faujas had been exploring the hilly districts of Vivarais and Velay in east-central France and found that the basalt there was also volcanic. (It resulted from regional volcanic activity in the Tertiary period which produced as its latest manifestation, particularly in central France, the very new-looking cones of ashes and associated lava flows.) It is not clear to what extent Faujas was familiar with Desmarest’s work, but his discoveries were at any rate independent, and he embodied them in 1778 in a great folio work on the anciently volcanoes of Vivarais and Velay (accounts of other researches were included). This work established once and for all that basalt, a rock important scientifically because of its distinctive characteristics, its widespread occurrence, and the manner of its association with other kinds of rock, was the product of volcanic action. The controversy over the origin of basalt was, however, by no means settled; the Wernerian (neptunist) view that it was an aqueous precipitate was vigorously advocated until well into the nineteenth century. In fact, Faujas himself was, except on this question, generally a neptunist.

In 1784 Faujas journeyed through England to Scotland; a full account was published in 1797. He narrated entertaining details of his travels and described arts, industries, and customs, but his most important observations were geological. He realized the volcanic nature of the basalt of the inner Hebrides and paid special attention to the spectacular columnar occurrence on the isle of Staffa, about which his curiosity had been aroused by Banks’s account in Thomas Pennant’s Second Tour of Scotland... (1774). (The Staffa basalt was recognized as of volcanic origin by Bishop Uno von Troil in his Letters From Iceland, 1780.) He also recognized the volcanic nature of the terraced hills in central Scotland, but he had no idea that these were vastly older (Paleozoic) than those of the western islands (Tertiary). His discrimination between the various kinds of dark, finegrained rocks was faulty. In particular, Faujas contradicted Whitehurst’s correct hypothesis regarding the basaltic nature of the Derbyshire toadstones, and he identified as old lavas some rocks that were unquestionably sedimentary in origin. Unfortunately, his specimens had been lost in a shipwreck on the way back to France; probably a more careful scrutiny of them would have prevented some of his mistakes.

In his monograph on the chalk of Maastricht, Faujas described a huge reptilian skull which he thought was that of a crocodile. Cuvier discussed this at length in his Ossems fossiles (V, pt. 2, [1824]), calling it a “marine serpent-like reptile”; the name mosasaur was proposed by the English geologist W. D. Conybeare in Cuvier’s volume. It is now placed as the representative of an extinct group among the lizards. This was perhaps the most notable discovery in the field of vertebrate paleontology up to that time.

BIBLIOGRAPHY

I. Original Works. Faujas’s main geological works are Recherches sur les volcans éteints du Vivarais et du Velay (Grenoble, 1778); Minéralogie des volcans (Paris, 1784); Voyage en Angleterre, en Écosse et aux Îles Hebrides, 2 vols. (Paris, 1797), also trans. into English, 2 vols. (London, 1799) and, later, with notes and a memoir by Archibald Geikie, 2 vols. (Glasgow, 1907); Histoire naturelle de la montagne de Saint-Pierre de Maestricht (Paris, 1799); and Essai de geologie, ou Memoires pour servir à l’histore naturelle du globe, 2 vols. (Paris, 1803–1809).

There is a very full bibliography of Faujas’s works, including his papers in the Annales du Muséum d’histoire naturelle (Paris), in Nouvelle biographie générale, XVII (Paris, 1856), 167–171; the work was reprinted at Copenhagen in 1963–1969. The list in the British Museum General Catalogue of Printed Books, photolith. ed., LXXI (London, 1960), cols. 274–276, is also very full as regards books. The reader should note, though, that in each source there are one or two items that are not in the other.

II. Secondary Literature. The chief source in English is A. Geikie, “Memoir of the Author,” in his ed. of the Voyage (see above). See also British Museum General Catalogue of Printed Books; J. Challinor, “The Early Progress of British Geology—III,” in Annals of Science, 10 (1954), 107–148, esp. 126–129; and T. D. Ford, “Barthélemy Faujas de St. Fond,” in Bulletin of the Peak District Mines Historical Society, 2 (1965), 236–240.

John Challinor