If he had really understood electricity, Alexander Graham Bell is reported to have once said, he would never have set about inventing it. But the inventor, who died 100 years ago on August 2, set to work - and on February 14, 1876, filed an application in the USA for patent number 174,465 for the "method and apparatus for the telegraphic transmission of spoken and other sounds, by causing electronic wave movements similar to the vibrations of sound-accompanying air", the telephone.

Preparatory work from Hesse

The Hessian inventor Johann Philipp Reis, who presented a telephone to the Physical Society in Frankfurt as early as 1861, was one of the pioneers. The spontaneously invented fantasy sentence "The horse won't eat cucumber salad" is said to have been sent through the machine during one of the first presentations. But the device only worked in one direction - it was impossible to answer.

Bell and his colleague Thomas Watson tried a different approach: using a diaphragm, they converted sound waves into electrical voltage fluctuations and sent them through an electrical cable, at the end of which they were converted back into sound. On June 2, 1875, they succeeded in transmitting sound electrically for the first time. Almost a year later, Watson is said to have heard the first sentence transmitted via a telephone in his study: "Watson, come here, I need you."

Flop at the world exhibition

Bell, who was born on March 3, 1847 in Edinburgh, Scotland, had already spent a lot of time working with language and communication. His father was a language educator and teacher for the deaf, and his son also took a job as a language teacher at a boarding school at the age of 16. A few years earlier, the family had emigrated to the USA. Two of Bell's brothers had died of tuberculosis and the family hoped to find a healthier climate on the other side of the Atlantic. Bell soon opened his own language school and then became a professor of speech physiology and linguistics at Boston University.

The pioneer of modern communication's groundbreaking invention initially attracted little attention. Even at the World's Fair in Philadelphia, the device, which had to be held alternately to the mouth and ear, went largely unnoticed. But Bell continued to work on improving his telephone. With the help of rented telegraph lines, he was able to talk to his assistant Watson over a distance of more than 200 kilometers by the end of 1876.

Precursor of the AT&T company founded

Interest followed. In April 1877, a businessman in the US East Coast metropolis of Boston had a permanent telephone connection set up between his home and his business. In July 1877, Bell and his supporters founded a telephone company named after him - the "Bell Telephone Company", which still exists today in a modified form as the telecommunications group "American Telephone and Telegraph Company" (AT&T). After just three weeks, the company was already renting out 25 new telephones a day.

One of the first public telephone networks was built in Berlin in 1881 with 48 subscribers. The connection to the exchange was established by means of a crank. The telephone made space and time seem to melt together, brought together the voices of people who were far apart, found its way into film, theater and music and increasingly became a cultural and historical asset.

From luxury item to everyday device

However, it initially remained a luxury item - and met with skepticism. The very early telephone directory, which appeared in Berlin in 1881, was called the "Book of Fools". "Now we've been trying to shut up our neighbors for ages, and now you come along and make everything much more difficult," the US writer Mark Twain, one of the first telephone owners in the city of Hartford, is said to have commented.

Meanwhile, Bell continued his research, financed by the proceeds of his telephone company - including on airplanes. He married a former student and moved with her to the Canadian Atlantic province of Nova Scotia, where he died on August 1, 1922 at the age of 75. In his honor, all telephone service in the USA was interrupted for one minute.