The early telephone technology was a result of research & development by numerous scientists and
researchers whereby each propelled the development by basing their work on earlier advancements achieved by other researchers.
The American Charles Grafton Page had in 1837 passed an electric current through a coil of wire placed between the poles of a horse shoe magnet whereby in so doing he was able to observe a phenomena he dubbed “galvanic music”simply by closing and opening the electric circuit. The “galvanic music” was a ringing sound in the magnet.
In1844 the Italian scientist Innocenzo Manzeti conceived the idea of the telephone and did extensive research on the idea which culminated in 1864.
Electric signals were used in 1860 by the German scientistJohann Philipp Reis to create an operational electromagnetic device capable of transmitting musical notes and speeches to a limited degree.
The Italian Antonio Meuci had invented a crude voice transmitter/receiver device in 1854.
In 1874 the American Elisha Gray had developed a ‘harmonic telegraph’ whereby vibrating steel reeds tuned to varying frequencies interrupted the current, which at the other end of the line passed through
electromagnets and vibrated matching tuned steel reeds near the electromagnet poles. This device was patented by Elisha Gray at the US patent office on 27thJuly 1875. On further development, Gray applied for a patent caveat on the US patent office for a telephone device on the same day (14th February
1876) as Alexander Graham Bell, due to the striking similarities between the two applications and
considering the two knew each other, one would suspect that either one of them had grabbed the idea of the other.
Alexander Graham Bell is credited for the development of the first functional, practical and commercially feasible telephone device. After extensive research on devises developed by his
predecessors Bell and his assistant Watson achieved a breakthrough on 10th March 1876 when testing their telephone devise. Bell spoke into the device, “Mr. Watson, come here I want to see you”, and a reply was made by Watson. Bell's telephone transmitter (microphone) consisted of a double electromagnet, infront of which a membrane, stretched on a ring, carried an oblong piece of soft iron cemented to its middle. A funnel-shaped mouthpiece directed the voice sounds upon the membrane, and as it vibrated, the soft iron "armature" induced corresponding currents in the coils of the electromagnet. These currents, after traversing the wire, passed through the receiver which consisted of an electromagnet in a tubular metal can having one end partially closed by a thin circular disc of soft iron. When the undulatory current passed through the coil of this electromagnet, the disc vibrated, thereby creating sound waves in the air.
This device was refined to a great extent by Bell and it was finally patented at the US patent office on
30th January 1877. To date Alexander Graham Bell is known as the inventor of the 1st telephone device.
Mganga,F.M (c) 2013
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