Showing posts with label Pantelegraph. Show all posts
Showing posts with label Pantelegraph. Show all posts

25 April 2019

Giovanni Caselli - inventor

Priest and physicist who created world’s first ‘fax' machine


Although Caselli was ordained as a priest in 1836 he devoted his life to the study of science
Although Caselli was ordained as a priest in
1836 he devoted his life to the study of science
Giovanni Caselli, a physics professor who invented the pantelegraph, the forerunner of the modern fax machine, was born on this day in 1815 in Siena.

Caselli developed a prototype pantelegraph, which was capable of transmitting handwriting and images over long distances via wire telegraph lines, in 1856, some 20 years ahead of the patenting of Alexander Graham Bell’s telephone in the United States. It entered commercial service in France in 1865.

The technology was patented in Europe and the United States in the 1860s, when it was also trialled in Great Britain and Russia, but ultimately in proved too unreliable to achieve universal acceptance and virtually disappeared from popular use until midway through the 20th century.

Caselli spent his early years in Florence studying physics, science, history and religion and was ordained as a priest in the Catholic Church when he was 21.

In 1841 he was appointed tutor to the sons of Count Marquis Sanvitale of Modena in Parma, where he spent eight years before his time there was abruptly ended by expulsion from the city as a result of his participation in an uprising against the ruling House of Austria-Este.

A model of Caselli's device can be seen at the Leonardo da Vinci museum in Milan
A model of Caselli's device can be seen
at the Leonardo da Vinci museum in Milan 
He returned to Florence in 1849, when he became a professor of physics at the University of Florence.  It was at this time that he began to study electrochemistry, electromagnetism, electricity and magnetism. He also launched a journal with the intention of explaining the science of physics in layman's terms.

Alexander Bain and Frederick Bakewell were two other physicists working on similar technology at the same time as Caselli but were unable to achieve the necessary synchronization between the transmitting and receiving parts so they would work together correctly. Caselli, though, built in a regulating clock that made the sending and receiving mechanisms work together.

In Caselli’s device, an image was made using non-conductive ink on tin foil, over which a stylus passed, lightly touching the foil, which conducted electricity where there was no ink and not where there was ink, causing circuit breaks that matched the image.

The signals were then sent along a long distance telegraph line to a receiver, where an electrical stylus reproduced the image line-by-line using blue dye ink on white paper.

In 1856, Caselli presented his prototype to Leopold II, Grand Duke of Tuscany, who was impressed enough to give Caselli some financial support, before he moved to Paris to introduce his invention to Napoleon III.

A 'fax' message that was transmitted between Paris and Lyon using Caselli's pantelegraph in 1862
A 'fax' message that was transmitted between Paris and
Lyon using Caselli's pantelegraph in 1862
Napoleon embraced the technology with great enthusiasm, and between 1857 and 1861 Caselli worked on perfecting his pantelegraph, sometimes known as the Autotelegraph or Universal Telegraph, with the French mechanical engineer Léon Foucault.

After seeing a demonstration of Caselli's improved pantelegraph in 1860, Napoleon gave Caselli the chance to test in within the French national telegraph network, providing him with financial backing. Among the successful tests was one between Paris and Amiens, over a distance of 140km (87 miles) of a document bearing the signature of the composer Gioachino Rossini. 

After a further successful test between Paris and Marseille, commercial operations started in 1865, first between Paris and Lyon line, extending to Marseille in 1867.

After patenting his device in Europe in 1861 the United States in 1863, and receiving the Legion d’Honneur from Napoleon in recognition for his work, Caselli oversaw trials in England and Russia, where Tsar Alexander II used the system to send documents between his palaces in Saint Petersburg and Moscow between 1861 and 1865.

In the first year of operation, Caselli’s pantelegraph transmitted almost 5,000 'faxes'.

Yet Caselli could not develop the technology quickly enough for reliability issues to be solved and eventually interest in it began to decline to the extent that he effectively abandoned it and returned to Florence, where he died in 1891 at the age of 76.

Although in the 1920s, the AT & T Corporation developed a way to transmit images using radio signals, it was not until 1964 that the Xerox Corporation introduced the first commercial fax machine of the kind recognisable today.

Many of Caselli’s patents, letters and proofs of teleautographic transmission are kept at the municipal library of Siena. Others can be found in the archives of the Museo Galileo in Florence.

The shell-shaped Piazza del Campo in Siena is regarded as one of the finest medieval squares in Europe
The shell-shaped Piazza del Campo in Siena is regarded
as one of the finest medieval squares in Europe
Travel tip: 

Siena, where Caselli was born, is famous for its shell-shaped Piazza del Campo, established in the 13th century as an open marketplace on a sloping site between the three communities that eventually merged to form Siena. It is regarded as one of Europe's finest medieval squares. The red brick paving, put down in 1349, fans out from the centre in nine sections. It has become well known as the scene of the historic horse race, the Palio di Siena.  Siena also has a beautiful Duomo - the Cathedral of St Mary of the Assumption - which was designed and completed between 1215 and 1263, its façade built in Tuscan Romanesque style using polychrome marble.


Piazza San Marco in Florence, a short distance from the centre of the city, is the home of the University of Florence
Piazza San Marco in Florence, a short distance from the centre
of the city, is the home of the University of Florence
Travel tip:

The University of Florence, the headquarters of which is in Piazza San Marco in the centre of the city, can trace its roots to the Studium Generale, which was established by the Florentine Republic in 1321. The Studium was recognized by Pope Clement VI in 1349, and included Italy’s first faculty of theology. The Studium became an imperial university in 1364, but was moved to Pisa in 1473 when Lorenzo the Magnificent gained control of Florence. Charles VIII moved it back from 1497–1515, but it was moved to Pisa again when the Medici family returned to power.  The modern university dates from 1859, when a group of institutions formed the Istituto di Studi Pratici e di Perfezionamento, which a year later was recognized as a full-fledged university, and renamed as the University of Florence in 1923.


More reading:

Antonio Meucci - the 'true' inventor of the telephone

Innocenzo Manzetti, the inventor who may have produced the first prototype telephone

The Italian physicist who pioneered the alternating current (AC) system

Also on this day:

Festa della Liberazione

1472: The death of Renaissance polymath Leon Battista Alberti

1973: The death of World War One flying ace Ferruccio Ranza

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