A fax before the telephone
Most people think of the fax machine as a late twentieth-century office device. Its basic idea is much older. The first patent for a system that could send an image by wire dates to 1843, more than three decades before the telephone, and it was granted to a Scottish clockmaker and inventor named Alexander Bain.
The claim “first fax machine” needs a caveat. Bain’s patent described a principle, and it is not clear how well, or whether, it was demonstrated as a working image transmitter in his lifetime. What can be said confidently is that his ideas set out the main elements that every later machine used: scanning, synchronization and a way of marking paper at the receiving end.
How Bain’s idea worked
Bain had worked on electric clocks, and he applied the same thinking to the telegraph. His 1843 British patent covered, among other things, a method of copying surfaces. The idea was to scan a flat original line by line with a stylus mounted on a swinging pendulum. If the stylus touched a raised metal part, the circuit was completed; if it touched a gap, it was not. At a distant station, a second pendulum, swinging in step with the first, moved a stylus across chemically treated paper. Where current arrived, the paper changed color, a chemical effect not unlike those used in early photography, and a copy gradually formed.
The weak point was synchronization. The two pendulums had to swing in exact time together. Bain suggested using electric clocks to keep them aligned, but the problem of keeping distant machines in step plagued all early facsimile systems.
Bakewell’s image telegraph
An English physicist, Frederick Bakewell, improved on the idea in the late 1840s. He wrote a message or drew a picture in non-conducting ink on tin foil wrapped around a rotating cylinder. A stylus scanned the foil in a spiral, and an identical cylinder at the receiving end, rotating in step with the first, produced a copy on chemically treated paper.
Bakewell’s machine was shown at the Great Exhibition in London in 1851 and attracted attention. It worked, but the pictures were crude, and as with all these systems, drift in synchronization could spoil the image. It remained a curiosity, partly because the telegraph already had a cheaper way of sending words.
Caselli and a working service
The Italian priest and physicist Giovanni Caselli built a better machine, which he called the pantelegraph, and patented it in the mid-1850s. It combined parts of earlier work, including an improved arrangement for keeping the sender and receiver synchronized using a pendulum mechanism.
Caselli’s machine reached a commercial stage. In 1865 a service began between Paris and Lyon, and it was later extended to other French cities. Customers could send handwriting, drawings and signatures, which made the system attractive for banks and businesses that wanted to confirm an authorized signature. The service ran for several years. It was not a mass medium, and it came to an end amid costs, technical limits and political changes in France.
Photographs by wire
Facsimile began to turn toward photographs in the early twentieth century. The German physicist Arthur Korn demonstrated sending photographs by wire around 1902, using a light-sensitive element made of selenium, and by about 1906 his equipment was in use between German cities. The French engineer Édouard Belin developed a smaller system that became known as the belinograph, which was used by newspapers.
Newspapers were the logical customers. A photograph of a news event could arrive in a distant newsroom in a shorter time than it would take to carry the print by train or ship. Later services such as news agency wirephoto networks in the 1930s relied on the same scanning principle, and some experiments used radio rather than wires. The principle was also developed for weather maps and charts.
These devices owed much to other technology of their time. Scanning used a rotating drum, a light source and a sensor, the same family of ideas behind later image scanners and, in a different way, television, which also scans pictures line by line using cathode ray tubes.
Why the office fax came late
The fax had to wait for several things. It needed a cheap, reliable way to scan and print a page at low cost. It needed telephone lines everywhere, so that any two offices could be connected. And it needed standards, so that machines from different makers could talk to each other. Copying technology such as xerography and later laser printers also made cheap paper output realistic. The first office-style machines began to appear in the 1960s, and standardized machines that worked over ordinary telephone lines spread widely in the 1980s. That later phase is a separate story from the 1840s inventions, but it grew from the same idea.
What the early history shows
The fax is a good example of an invention that existed in principle long before the surrounding technology made it useful. Bain, Bakewell and Caselli all had working ideas, but without cheap electronics and an extensive telephone network, the machines stayed specialized. When those conditions arrived, the concept was ready.