We all know the inventor of telephone is Alexander Graham Bell. But direct invention of telephone had not happen. There was lot of inventions and discoveries leads to invention of Telephone. let's see what are all those:

The concept telephone initiated with Tin Can technology, this invention happened in the year 1667. A brief introduction about this topic I had already written a blog you can check there. 

Speaking Tubes  concept was proposed by Gottfried in the year 1796. New version of this is Megaphones.

You may all heard about Telegraph, a device used for transmitting and receiving messages electrically.

The idea of Speaking telegraph was suggested by Innocenzo Manzetti in the year 1844. Unfortunately this was proven as a rumor. No such speaking telegraphy was demonstrated until Bell Telephone demonstration. 

Later in 1854 Electric transmission of speech was published in an article this was demonstrated by Reis but this is only for musical sounds not for speech transmission. 

In 1875 Alexander Graham Bell's U.S patent on Transmitters and receivers for Electric Telegraphs is granted. This can transmit and receives the speech properly without any major errors.

Now what we are using is a Electromagnetic Telephones this was also proposed then by applying for patent on Electromagnetic Telegraphy and successfully granted. But major difference between then and now is at that time they have demonstrated using Amplitude modulation but now is different modulation techniques.

A scientist called Gray also applied for patent on the same topic called electromagnetic Telegraphy on the same date that Graham Bell applied but he got notified by patent office as interference between Bell's work and his work later Gray abandoned his patent application.

Liquid Transmitter was invented in 1876 and this was used to transmit the sentence called “ Mr. Watson, come here! I want to see you!”. The receiver used in this process is Electromagnetic.

Worlds first long distance call was happened on 10th August 1876 upto the distance of 13kms.

We experience a ring before connects to the destination at that time when Bell invented there was no ringer for hi Telephone later in the year 1877 one company includes a Ringer for Telephones and made it commercial. The ringer was made using Siemens pipe.

After this many inventions and developments have been done on Telephone and it is now we are at the Mobile Phone Era not the Telephones.

This is all about the history behind Telephone invention and their contributions.