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Dead medium: Caselli's Pantelegraph (Part One)
From: From: (Bruce Sterling)
Source(s): "Caselli's Pantelegraph" by Julien Feydy.- Musee des arts et metiers *La Revue,* June 1995, n 11, p.50-57.

(((A beautifully written, classic article placed on the Web from one of the great global centers of dead media production, France -- bruces)))


"Both Christophe in his *The Fenouillard Family,* written in 1893, and Jules Verne in his recently discovered manuscript *Paris in the 20th Century* dating from 1863, mention a process enabling the long-distance transmission of drawings, ideograms or facsimiles: the Caselli pantelegraph.

"Its inventor, Giovanni Caselli, born in Siena in 1815, was the incumbent of an ecclesiastical living. While teaching physics at the University of Florence, he devoted his research to making progress in the telegraphic transmission of images, an issue which had been proving a stumbling block for several researchers for quite a few years, including the Britons Bain and Bakewell, due to a failure to achieve a perfect synchronization between transmitting and receiving devices.

"In 1856, the results were conclusive enough for the Grand Duke of Tuscany to take an interest in Caselli's invention and, the following year, Caselli went to Paris where he was to be given decisive help by the famous inventor and mechanical engineer Paul Gustave Froment, to whom he had been recommended by Foucault, who had already entrusted Caselli with the task of making his pendulum.

"Once completed, the final device met with unequivocal enthusiasm from the Parisian scientific world and a Pantelegraph Society was created to prepare its exploitation.

"What is more, the Emperor Napoleon III himself, passionately interested in mechanics and modern inventions, visited Froment's workshops on May 10th 1860 to watch a demonstration of the device. The enthusiastic Emperor gave Caselli access to the lines he needed in order to continue his experiments in Paris, from the

Froment workshops to the Observatory. Then, in November of the same year, a telegraphic line was also allocated to Caselli between Paris and Amiens to enable a real inter- city experiment, which was apparently a total success.

"Caselli had in fact managed to eliminate the last remaining fault in his machine by making the synchronization timers independent of the current relayed by the telegraphic line itself, which was too sensitive to atmospheric disturbances.

"The French press was brimming with laudatory articles on the pantelegraph, while the top brass from high society and the scientific and administrative worlds hurried along to Froment's workshops to find out about the new process. In September 1861, King Victor-Emmanuel invited Caselli and his machines to a series of triumphant demonstrations at the Florence Exhibition.

"Finally, in 1863, the French Legislature and Council of State adopted texts authorizing the official exploitation of an initial line between Paris and Marseille, while across the Channel, Caselli obtained authorization for the experimental use of a line between London and Liverpool over a four-month period."