Rus Articles Journal

Why unit of sound intensity is called by the name of the teacher of deaf-and-dumb children?

Alexander Grekhem Bell was born on March 3, 1847. He was surdopedagogy - learned to talk deaf-and-dumb children. Alexander`s father developed many years system of record of sounds of the speech, using which, people could pronounce correctly words in any language - from English to Chinese. And the most part of scientific works and inventions Bella - the son was devoted to improvement of achievements of the father and creation of means of communication for deaf-mutes.

Bell designed devices for demonstration by the deaf of an articulation. For this purpose studied acoustics, physics of the human speech. It began to put experiences with the device in which the membrane transferred fluctuations of sounds to a needle. Bell would invent a phonograph before Edison, but he was interested only in a graphic sound recording, but not his further reproduction which deafs would not hear.

Once, in 70 - e years, he learned that the cable company Western Union promises the huge sum to the one who will be able to transfer several telegrams on one wire at the same time. He decided to try to apply the acoustic experiment to simultaneous transfer of different musical tones on a cable wire here.

Without being a physicist, he invited the assistant - the expert. Bell also discussed the ideas with various scientists working in this area. In particular, spring of 1875 Bell decided to learn opinion of the most visible American scientist, aged Joseph Henry whose name called inductance unit now. Henry grabbed an essence of idea at once and advised Bella not to give up these researches at all.

And in a year Bell incidentally found out that his device can transmit not cable signals, but the human speech. This invention did not interest the " company; Western Union who expected multichannel telegraph, and Bell did not receive from it any money. But just in case patented the invention. And correctly made!

inflamed Later the whole dispute for a priority in the invention of phone. So Bell called the creation.

The patent granted Bella was one of the most valuable patents in the United States. Later it brought it millions of dollars. In 1877 Bell Telephone Company, one of the companies, known in the world was based (in particular, in laboratory of the company in 1947 the transistor was invented). In further Bell invented fotofon - the device for transfer of a human voice by means of light beams, the audiometer - the device for measurement of level of a sound, induction balance (in fact, the first metal detector) and many other devices.

All Bell took out 26 patents for inventions among which, except various electric devices, there were aircraft and hydroairplanes. At the same time Bell did not stop work on a surdopedagogika, physiology, eugenics. In 1918. its book " was published; The Longevity and conditions connected with its extension . Now there is physical unit - Bell. It is a decimal logarithm of the relation of capacities of two signals. The physical nature of the compared capacities does not make a reservation and, in essence, there can be any - electric, acoustic, mechanical - it is important only that the power of both signals was expressed in identical units.

Alexander Grekhem Bell died on August 2, 1922]