Charles Grafton Page
American Charles Grafton Page (1812-1868) in 1837 passed an electric current through a coil of wire placed between the poles of a horseshoe magnet. He observed that connecting and disconnecting the current caused a ringing sound in the magnet. He called this effect "galvanic music."
Innocenzo Manzetti
Innocenzo Manzetti considered the idea of a telephone as early as 1844, and may have made one in 1864, as an enhancement to an automaton built by him in 1849.
This make-or-break signaling was able to transmit tones and some vowels, but since it did not follow the analog shape of the sound wave (the contact was pure digital, on or off) it could not transmit consonants, or complex sounds. Bourseul's phrase "make and break the current" was inaccurately applied to later work by Philipp Reis who successfully transmitted faint voice sounds with unbroken current.[3]
Thomas Edison tested the Reis equipment and found that "single words, uttered as in reading, speaking and the like, were perceptible indistinctly, notwithstanding here also the inflections of the voice, the modulations of interrogation, wonder, command, etc., attained distinct expression."
Prior to 1947, the Reis device was tested by the British company Standard Telephones and Cables (STC). The results also confirmed it could faintly transmit and receive speech. At the time STC was bidding for a contract with Alexander Graham Bell's American Telephone and Telegraph Company, and the results were covered up by STC's chairman Sir Frank Gill to maintain Bell's reputation.
An early voice communicating device was invented around 1854 by Antonio Meucci, who called it a telettrofono. In 1871 Meucci filed a caveat at the US Patent Office. His caveat describes his invention, but does not mention a diaphragm, electromagnet, conversion of sound into electrical waves, conversion of electrical waves into sound, or other essential features of an electromagnetic telephone.
The first American demonstration of Meucci's invention took place in Staten Island, New York in 1854. In 1860, a description of it was reportedly published in an Italian-language New York newspaper, although no known copy of that newspaper issue or article survived to the present day. Meucci claimed to have invented a paired electro-magnetic transmitter and receiver, where the motion of a diaphragm modulated a signal in a coil by moving an electromagnet, although this was not mentioned in his 1871 U.S. patent caveat. A further discrepancy observed was that the device described in the 1871 caveat employed only a single conduction wire, with the telephone's transmitter-receivers being insulated from a 'ground return' path.
In the 1880s Meucci was credited with the early invention of inductive loading of telephone wires to increase long-distance signals. Unfortunately, serious burns from an accident, a lack of English, and poor business abilities resulted in Meucci failing to develop his inventions commercially in America. Meucci demonstrated some sort of instrument in 1849 in Havana, Cuba, but the evidence is clear that this was not an electromagnetic telephone and may have been a variant of a string telephone that used wire. Meucci has been further credited with invention of an anti-sidetone circuit. However, examination showed that his solution to sidetone was to maintain two separate telephone circuits, and thus use twice as many transmission wires. The anti-sidetone circuit later introduced by Bell Telephone instead cancelled sidetone through a feedback process.
An American District Telegraph (ADT) laboratory reportedly lost some of Meucci's working models, his wife reportedly disposed of others and Meucci, who sometimes lived on public assistance, chose not to renew his 1871 teletrofono patent caveat after 1874.
Meucci was recognized for his pioneering work on the telephone by the United States House of Representatives in 2002. The resolution stated that "if Meucci had been able to pay the $10 fee to maintain the caveat after 1874, no patent could have been issued to Bell." No such patent could have issued to Bell in March 1876. If Meucci had renewed his caveat, he would have been given an opportunity to prove to the examiner that the device described in his caveat was the electromagnetic telephone described in Bell's patent application.
The Meucci resolution by the US Congress was promptly followed by a Canada legislative motion by Canada's 37th Parliament, declaring Alexander Graham Bell as the inventor of the telephone. Others in Canada disagreed with the Congressional resolution, some of whom provided criticisms of both its accuracy and intent.
American Charles Grafton Page (1812-1868) in 1837 passed an electric current through a coil of wire placed between the poles of a horseshoe magnet. He observed that connecting and disconnecting the current caused a ringing sound in the magnet. He called this effect "galvanic music."
Innocenzo Manzetti
Innocenzo Manzetti considered the idea of a telephone as early as 1844, and may have made one in 1864, as an enhancement to an automaton built by him in 1849.
Charles Bourseul
In 1854 Charles Bourseul, a French telegrapher, published a plan for conveying sounds and even speech by electricity in the magazine L'Illustration Paris.Bourseul's ideas were also published in Didaskalia (Frankfurt am Main) on September 28, 1854: "Suppose", he explained, “that a man speaks near a movable disc sufficiently flexible to lose none of the vibrations of the voice; that this disc alternately makes and breaks the currents from a battery: you may have at a distance another disc which will simultaneously execute the same vibrations.... It is certain that, in a more or less distant future, speech will be transmitted by electricity. I have made experiments in this direction; they are delicate and demand time and patience, but the approximations obtained promise a favourable result."This make-or-break signaling was able to transmit tones and some vowels, but since it did not follow the analog shape of the sound wave (the contact was pure digital, on or off) it could not transmit consonants, or complex sounds. Bourseul's phrase "make and break the current" was inaccurately applied to later work by Philipp Reis who successfully transmitted faint voice sounds with unbroken current.[3]
Johann Philipp Reis
In 1860 Johann Philipp Reis produced a device that could transmit musical notes, indistinct speech, and occasionally distinct speech. The first sentence spoken on it was "Das Pferd frisst keinen Gurkensalat" (the horse doesn't eat cucumber salad). In the Reis transmitter, a diaphragm was attached to a needle that pressed against a metal contact. This resembled the make-or-break design of Bourseul, although Reis used the term "molecular motion" (molekulare Bewegung) to describe the contact points of his transmitter.[4] The Reis transmitter was very difficult to operate, since the relative position of the needle and the contact were critical to the device's operation. This can be called a "telephone", since it did transmit voice sounds over distance, but was hardly a commercially practical telephone in the modern sense, as it failed to reliably transmit a good copy of any supplied sound.#Thomas Edison tested the Reis equipment and found that "single words, uttered as in reading, speaking and the like, were perceptible indistinctly, notwithstanding here also the inflections of the voice, the modulations of interrogation, wonder, command, etc., attained distinct expression."
Prior to 1947, the Reis device was tested by the British company Standard Telephones and Cables (STC). The results also confirmed it could faintly transmit and receive speech. At the time STC was bidding for a contract with Alexander Graham Bell's American Telephone and Telegraph Company, and the results were covered up by STC's chairman Sir Frank Gill to maintain Bell's reputation.
Antonio Meucci
The first American demonstration of Meucci's invention took place in Staten Island, New York in 1854. In 1860, a description of it was reportedly published in an Italian-language New York newspaper, although no known copy of that newspaper issue or article survived to the present day. Meucci claimed to have invented a paired electro-magnetic transmitter and receiver, where the motion of a diaphragm modulated a signal in a coil by moving an electromagnet, although this was not mentioned in his 1871 U.S. patent caveat. A further discrepancy observed was that the device described in the 1871 caveat employed only a single conduction wire, with the telephone's transmitter-receivers being insulated from a 'ground return' path.
In the 1880s Meucci was credited with the early invention of inductive loading of telephone wires to increase long-distance signals. Unfortunately, serious burns from an accident, a lack of English, and poor business abilities resulted in Meucci failing to develop his inventions commercially in America. Meucci demonstrated some sort of instrument in 1849 in Havana, Cuba, but the evidence is clear that this was not an electromagnetic telephone and may have been a variant of a string telephone that used wire. Meucci has been further credited with invention of an anti-sidetone circuit. However, examination showed that his solution to sidetone was to maintain two separate telephone circuits, and thus use twice as many transmission wires. The anti-sidetone circuit later introduced by Bell Telephone instead cancelled sidetone through a feedback process.
An American District Telegraph (ADT) laboratory reportedly lost some of Meucci's working models, his wife reportedly disposed of others and Meucci, who sometimes lived on public assistance, chose not to renew his 1871 teletrofono patent caveat after 1874.
Meucci was recognized for his pioneering work on the telephone by the United States House of Representatives in 2002. The resolution stated that "if Meucci had been able to pay the $10 fee to maintain the caveat after 1874, no patent could have been issued to Bell." No such patent could have issued to Bell in March 1876. If Meucci had renewed his caveat, he would have been given an opportunity to prove to the examiner that the device described in his caveat was the electromagnetic telephone described in Bell's patent application.
The Meucci resolution by the US Congress was promptly followed by a Canada legislative motion by Canada's 37th Parliament, declaring Alexander Graham Bell as the inventor of the telephone. Others in Canada disagreed with the Congressional resolution, some of whom provided criticisms of both its accuracy and intent.
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