It was called Pantelegrafo, transmitted signatures and scores via telegraph and was the work of a Sienese abbot
The first telephax is Italian and was invented in 1856 by the Sienese abbot Giovanni Caselli. It was called “panthelegraph” (from the Greek pan-hillé-graphos, or universal distance writing) and was an electromechanical device capable of transmitting manuscript images and texts using the telegraph line, practically a scanner and a fax ante litteram. Caselli, born in 1815, was interested after the ecclesiastical order in Florence, mathematics and physics and in particular in the nascent branch of electromagnetism. It was together with the French physicist Alexandre Bain who put knowledge in the electromechanical field into practice for the realization of the first tool that allowed to send long -distance texts and images by telegraph.
Distance writing before the phone
The panthelegraph worked through a line of line scan principle: the message to be sent was written with an insulating ink on a special tablet covered with a conductive paint. The written parts were therefore not conductive and created a sort of “electric negative”. A mobile nib flowed on the tablet and, when it touched a conduction area, the current passed, while when it met the insulating ink, the current stopped.
The synchronism between the transmitter and the receiver was guaranteed by perfectly synchronized electric pendulums, a solution that ensured that the nibs in both devices (transmitter and recipient) moved synchronously. The receiver, on the other hand, used a sheet of paper soaked with chemical salts sensitive to the current, such as potassium ferrocyanide. When the current came, a chemical reaction took place that left a blue sign on the paper. In the absence of current, no sign was traced. In this way, the drawing or text written at the origin was faithfully reproduced on the sheet of the receiver appliance.
The system was able to transmit complex designs, signatures, texts and even musical scores. The transmission time for a page was about 8-12 minutes, with an incredibly high quality for the time. The panthelegraph, patented in France in 1856, was successfully adopted on the Paris -Lyon telegraph line. The great composer Gioacchino Rossini also tried the Italian abbot device. Giovanni Caselli did not draw economic advantages from his prodigious tool and died in Florence in a modest house in 1891. A replica of the panthelegraph is located at the Museum of Science and Technology in Milan.
