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Giovanni Caselli

b. 1815, Siena, Italy
d. 1891, Florence, Italy

The pantelegraph developed by Giovanni Caselli was a system of sending and receiving images over long distances by means of telegraph. The images transmitted by telegraph were reproduced using electrochemistry. This system was actually the first prototype of a fax machine.

Giovanni Caselli, an Italian physicist, has an interesting history. He was born in Siena in 1815 and studied literature and science. From 1841 to 1849 he lived in Modena as a tutor of the sons of Marquis of San Vitale, but as he took part in the riots for annexation of Duchy of Modena to Piedmont, he was expelled from the Duchy.

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 over quite a few years for several researchers including the Britons Bain and Bakewell. Their problems were due to a failure to achieve a perfect synchronisation 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. Here he was to be given decisive help by the famous inventor and mechanical engineer Paul Gustave Froment. In 1862 Giovanni Caselli built a machine he called a "pantelegraph" (Pantèlègraphe) (the word is a combination of "pantograph", a tool that copies drawing, and "telegraph", a machine that sends messages over a wire.)

Caselli leaped ahead of his contempory inventors with his pantelegraph or Universal Telegraph, and included a "synchronizing apparatus" to help two machines work together. This unique machine was a precursor of what is now commonly known as the fax machine. Once completed, Castelli's 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.

In November of the same year, a telegraphic line was also allocated to Caselli between Paris and Amiens to enable a real intercity 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 pantelegraph, Caselli's first invention, was registered in 1861. 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. In 1865 the pantelegraph started its duty between Paris and Lyon, duty which ended in 1870 following the defeat of Sedan. The pantelegraph system transmited nearly 5,000 faxes in the first year.

Made of cast iron and standing more than 2 m high, this primitive, but effective machine worked as follows. The sender wrote a message on a sheet of tin in non-conducting ink. The sheet was then fixed to a curved metal plate. The stylus of the transmitter scanning an original document by moving across its parallel lines (three lines per millimetre). The signals were carried by telegraph to the marked out the message in Prussian blue ink, the colour produced by a chemical reaction, as the paper was soaked in potassium ferrocyanide. To ensure that both needles scanned at exactly the same rate, two extremely accurate clocks were used to trigger a pendulum which, in turn, was linked to gears and pulleys that controlled the needles.

At the time in which the Paris-Lyon Pantelegraph worked regularly, Napoleon, having in vain offered to Caselli the French citizenship to allow him accede to the rank of general inspector and co-ordinator of the French telegraph, awarded him the Legion of Honor. The Pantelegraph worked also between London and Liverpool in order to build up a public service. But the program was withheld because of the economical crisis which, in 1864 hit England and the Financial Society, with which Caselli had undertaken the final agreements. Even Russia was interested in his Pantelegraph, but instead of creating a public service, it was used to send messages between the two imperial residences of St. Petersburg and Moscow.

However, Caselli's system seems to have suffered from a number of deficiencies, and although it continued in use for some years on the telegraph lines around Le Havre and Lyons, it did not realise the hopes of its promoters, as the transmissions were often illegible. Probably this was because of the continuing difficulty of keeping the transmitter and receiver in synchronization.

The Pantelegraph Society did not prove equal to the market which was apparently opening up and, failing to undertake any energetic promotion of the device, was content to wait passively for its capital to be remunerated via the flood of orders which which were supposed to pour in from all over the world.

In Italy, after an initially euphoric reception, the sluggishness of the administration and haughtiness of ministers led Caselli to give up any further development of his invention. In France, he clashed with the Telegraphs administration which, fearing competition with its ordinary telegraphic network, refused to lower the tariff for handwritten dispatches - which were nevertheless prohibitive - and even advised taxing such dispatches at a higher rate than ordinary ones.

Sadly enough, Caselli's invention was introduced at a time when the World had started to invest heavily in conventional telegraph services. When the pantelegraph appeared, France was in fact in the process of setting up a complete telegraphic network, using the Hugues, Morse and then Baudot systems, replacing the former Chappe optical telegraph, which had been experimented since 1792. More than just a technical step forward, a qualitative transformation in the use of the telegraph system was underway. What had until then been an instrument of the governing powers and the stock exchange, was about to establish itself as a relatively commonplace means of communication, conveying a variety of urgent yet trivial pieces of news such as births, deaths, marriages or tourist hotel reservations.

Designed to transmit images, the pantelegraph, like today's fax, was perfectly able to transmit written texts correctly. However, whether conscious or not, there was a general refusal to allow it any other other role than the transmission of a banking signature or a trademark, since this was the only system capable of doing so, and the administration went on to ensure it was gently stifled out of existence.

In 1863, two top civil servants from the Chinese Empire requested a demonstration at the Froment workshops and could not hide their amazement and admiration in the face of an invention which, in one swoop, solved the tricky problem of the telegraphic transmission of ideograms. In 1884, fairly far-reaching negotiations appear to have taken place between China and Italy with the aim of carrying out experiments on the Caselli pantelegraph in Peking, but these were not followed up. However, this particular use of the telegraph, anticipated very early on by Caselli, was taken up much later by the Japanese, to whom we owe the massive diffusion of the fax.

Today, pantelegraphs lie dormant in a few rare museums. Those kept at the Musée National des Techniques were given another chance to prove their reliability in 1961, between Paris and Marseille, during the commemoration of the first tests, and in 1982, at the Postal Museum in Riquewihr, where they operated faultlessly, six hours a day, for several months.

Some of other Caselli's inventions were: an electrical marine torpedo which came back to the launching point in the event of missing the mark, an hydraulic press and an instrument that measures the speed of the locomotives.

In the minds of the public, the pantelegraph was associated exclusively with the transmission of images. The advantages of also using it to send text were only dimly perceived in the 1860s. The Pantelegraph company in Paris did little to improve the situation, making only feeble efforts to promote its services. Convinced of the superiority of its technology, it was content to wait for investors to appear. None did, however, and the Pantelegraph company was eventually squeezed out of the market - an early example of how a new and superior technology failed to gain a foothold because an earlier technology was already established.

Caselli's invention subsequently fell into disuse and he died a disappointed man in Florence in 1891.

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