One hundred years of continental drift: the early Italian reaction to Wegener’s ‘visionary’ theory

Abstract

One hundred years ago in 1915 ‘Die Entstehung der Kontinente und Ozeane’ by Alfred Wegener was published, destined to become one of the most controversial geological opus in the first half of the twentieth century. Wegener is the first to combine the most diverse geological (sensu lato) evidences in a single great synthesis. Nonetheless, apart from few upholders, the initial reaction to the drift hypothesis was fierce opposition, and the strongest criticism came from geophysics, the same discipline that, paradoxically, starting from the 1950s led to the Plate Tectonics revolution and, ultimately, to a complete re-evaluation of Wegener’s hypothesis. In the present paper we discuss the initial reaction of Italian scientists to the original continental drift theory, with particular focus on the period between the two world wars. Italian geologists like Fossa-Mancini and Gortani were almost favourable to the new theory, while authors such as Vardabasso and Sacco were neutral or even hostile to the new hypothesis, so iconoclastic for the widely accepted fixist vision of the time. In any case, all these scientists agreed that the new theory had great potential for reopening an enthusiastic debate on issues that were given as established paradigms – the genuine way for progress in science.