Abbot and Inventor: Giovanni Caselli, the Pantelegraph, and Catholic Science in the 19th Century, by Carlo Bovolo, Università di Torino

In 1860 the famous composer Gioacchino Rossini sent an autographed text from Paris to Amiens, a distance of about 140 km, in only a few minutes. To celebrate such an important event, the musician wrote a piece for piano, the ‘Allegretto del pantelegrafo’. What made the incredibly fast transmission possible was the invention of an Italian priest: in the middle of the nineteenth century, the abbot Giovanni Caselli (1815–1891) had created the pantelegraph (a portmanteau of the words pantograph and telegraph – Figure 1), which, anticipating the facsimile machine, was able to send handwritten texts and pictures by telegraph.

Caselli, a priest from Siena devoted to physics, realized a prototype of the pantelegraph in Florence in 1856, a technology which mixed telegraphy and electrochemistry and whose operation was based on a regulating clock. Searching for funding, he then moved to Paris, where he improved his instrument thanks to Paule-Gustave Froment and attracted the attention of the public and of Napoleon III.

The French government funded further research and experiments, including Rossini’s transmission in 1860. The experiments were successful: in 1864 the French government officially adopted the pantelegraph, establishing lines between Paris, Lyon, and Marseille. Other short lines were built in England, Russia, and China.

At the Italian national exhibition in Florence in 1861 and, above all, at the Universal Exhibition in Paris in 1867, the pantelegraph reached the pinnacle of its success: public demonstrations were made, newspapers described its functioning and extolled its advantages, and Caselli was celebrated as a brilliant inventor. However, its success – though intense – was short. Due to the complexity of the technology, its costs, and an incomplete understanding of its potential, the pantelegraphic network remained very limited and was dismantled in subsequent years. Caselli (inventor also of a cinemograph for measuring the speed of trains, a nautical electric torpedo, and a hydromagnetic rudder) returned to Italy, where he died in Florence in 1891.

Despite the parable of the pantelegraph, Caselli became a hero of the Catholic apologetics of science: in the apologetical and propagandistic discourse about science and technology proposed by the Catholic press in the second half of nineteenth century, the inventor-priest was a symbol of the Catholic contribution to scientific and technological progress, represented a rebuttal to accusations of obscurantism against the Church, and laid claim to a public role for Catholicism in science.

Carlo’s research was funded by a 2020 SIS Grant. A longer piece on this subject will feature in a future SIS Bulletin.