Innocenzo Manzetti first mooted the idea of a “speaking telegraph” (telephone).
Drawing a Draft
Antonio Meucci demonstrates a communicating device to individuals in Havana. It is disputed if this is an electromagnetic telephone, but is said to involve direct transmission of electricity into the body.
Charles Bourseul publishes a description of a make-break telephone transmitter and receiver in L'Illustration, (Paris) but does not construct a working instrument
Try to Understand me!
Antonio Meucci demonstrates an electric voice operated device in New York, but it is not clear what kind of device he demonstrated.
The German Johann Philipp Reis demonstrates a make-break transmitter after the design of Bourseul and a knitting needle receiver. Witnesses said they heard human voices being transmitted.
I can hear you!!
Johann Philipp Reis manages to transfer voice electrically over a distance of 340 feet
I did it!!
In an attempt to give his musical automaton a voice, Innocenzo Manzetti invents the 'Speaking telegraph'. He shows no interest in patenting his device, but it is reported in newspapers.
Can you hear me????
Meucci reads of Manzetti's invention and writes to the editors of two newspapers claiming priority and quoting his first experiment in 1849. He writes "I do not wish to deny Mr. Manzetti his invention, I only wish to observe that two thoughts could be found to contain the same discovery, and that by uniting the two ideas one can more easily reach the certainty about a thing this important." If he reads Meucci's offer of collaboration, Manzetti does not respond.
I got a patent!
Antonio Meucci files a patent caveat (a statement of intention to patent) for a Sound Telegraph, but it does not describe an electromagnetic telephone.
I'll say it for you!!!
Prof Vanderwyde demonstrated Reis's telephone in New York.
noting some facts down
Thomas Edison notes variable resistance in carbon grains due to pressure, builds a rheostat based on the principle but abandons it because of its sensitivity to vibration.
Gray invents electromagnet device for transmitting musical tones. Some of his receivers use a metallic diaphragm.
Gray demonstrates his musical tones device and transmitted "familiar melodies through telegraph wire" at the Presbyterian Church in Highland Park, Illinois.
an electro-dynamic receiver
1875 Thomas Edison experiments with acoustic telegraphy and in November builds an electro-dynamic receiver but does not exploit it.
a plucked steel reed
Alexander Graham Bell transmits the sound of a plucked steel reed using electromagnet instruments.
starting to work
Bell uses a bi-directional "gallows" telephone that was able to transmit "indistinct but voicelike sounds" but not clear speech. Both the transmitter and the receiver were identical
The liquid transmitter
11 February 1876 Elisha Gray invents liquid transmitter for use with a telephone, but does not build one.
(about 9:30am) Gray or his lawyer brings to the Patent Office Gray's caveat for the telephone. (A caveat was like a patent application without claims to notify the patent office of an invention in process.)
14 February 1876 (about 1:30pm) Approximately two hours later Elisha Gray's caveat was registered in the cash blotter. Although his caveat was not a full application, Gray could have converted it into a patent application, but did not do so because of advice from his lawyer and his involvement with acoustic telegraphy. The result was that the patent was awarded to Bell.
I got a patent too!!
(about 11:30am) Bell's lawyer brings to the Patent Office Bell's patent application for the telephone. Bell's lawyer requested that it be registered immediately in the cash receipts blotter.
7 March 1876 Bell's US patent No. 174,465 for the telephone is granted.
10 March 1876 Bell transmits speech "Mr. Watson, come here! I want to see you!" using a liquid transmitter as described in Gray's caveat, and an electromagnetic receiver.
first patent application for acoustic telegraphy
16 May 1876 Thomas Edison files first patent application for acoustic telegraphy for which US patent 182,996 was granted October 10, 1876.
The first 6mile telephone
10 August 1876 Alexander Graham Bell makes the world's first long distance telephone call, about 6 miles between Brantford and Paris, Ontario, Canada
The carbon microphone
October 1876 Thomas Edison tests his first carbon microphone.
The first two-way long distance telephone call
9 October 1876 Bell makes the first two-way long distance telephone call between Cambridge and Boston, Massachusetts, USA.
First long-distance telephone
1877: First long-distance telephone line in French Corral, California