ELISHA GRAY

And the development of the musical(acoustic) telegraph.Ciaran Keane, Egne Oispuu, Ray Dineen, Abby Livingstone

OUR AIMS Ciarán - Elisha Gray Biography

Egne - Legal dispute / Telephone

Ray - Musical Telegraph Abby - Development

BIOGRAPHY Born (1835) in Barnesville Ohio

Worked at young age – Oberlin Taught and invented there Inventing for his entire life Died 1901 aged 65

INVENTIONS Self-adjusting telegraph relay Needle annunciator for elevators Telautograph Telephote (Early television) Telephone - disputed / no patent Musical telegraph

CONTROVERSY BETWEEN ELISHA GRAY AND A. GRAHAM BELL A.Graham Bell and Elisha Gray. Who

invented the telephone? Did A.Graham Bell steal the telephone invention from Gray?

14, February 1876 Gray’s lawyer filed in a patent caveat to U.S. Patent office. The same day Bell’s lawyer hand-delivered Bell’s patent application for telephone.

Bell’s application was suspended for 3 months to see who actually invented the telephone.

SUSPICION OVER A.GRAHAM BELL’S INVENTION On 24th of February 1876 Bell flew to

Washington DC. By that time he had no recordings in his lab notebook. After he flew back to Boston on 7th of March 1876 he recorded a diagram very similar to Gray’s one.(Picture on the next slide)

Bell admits to Gray that he was aware of Gray’s telephone patent caveat although by that time Gray’s patent caveat was still confidential.

GRAY’S (LEFT) AND BELL’S (RIGHT) DIAGRAM

AFFIDAVIT FROM ZENAS FISK WILBER On 6th of April,1886, Zenas Fisk Wilber

made a sworn affidavit where he told that he showed Gray’s drawing to his long-time friend Marcellus Bailey(Bell’s lawyer) and later to Bell himself.

On 22nd of May 1886, Wilber’s affidavit was published in the Washington Post. On 25th of May, 1886, Washington Post published a sworn denial from Bell.

BELL WON THE CASE!

Gray’s and Bell’s case over the telephone patent was one of the most famous cases in the history.

Although the case was more than 125 years ago, there are people who are still looking for the proof that Gray invented the telephone. And at the same time Bell supporters are looking proof for saying that he was innocent

Nonetheless Gray didn’t stop inventing and later in the 1876 he invented the first musical telegraph.

MUSICAL TELEGRAPH

Elisha Gray accidently discovered that he could control sound from a self vibrating electromagnetic circuit.

He used steel rods to act as a medium for sound as they vibrated. They produced a different pitch depending on the frequency of the vibrations. These are called oscillators.

MUSICAL TELEGRAPH

The sound/vibrations cause interruptions in a near by electromagnet which them proceeds to send the signal though telegraph lines to the destination.

In later models Gray made a simple loudspeaker for the destination point which created the first electromechanical musical device.

MUSICAL TELEGRAPH

Gray used several oscillators for his new invention. Each were linked to different keys of the key board and were assigned a different pitch.

Grays keyboard was able to play 2 octaves.

MUSICAL TELEGRAPH PARTS

A telegraphic circuit composed in part of animal tissue.

A resonant receiver, which is also a conductor of electricity.

MUSICAL TELEGRAPH PARTS

A series of circuit breakers capable of producing musical tones of different pitch

A corresponding series of keys for throwing the circuit breakers into operation, where by several tones simultaneously may be transmitted through a single wire.

RESOURCES

The telephone patent conspiracy of 1876 by A.Edward. Chicago, Illinois, United States Pateent Office, July 27 1875.

“Improvement in electric telegraphs for transmitting musical tones.” http://

en.wikipedia.org/wiki/Elisha_Gray_and_Alexander_Bell_telephone_controversy

http://en.wikipedia.org/wiki/Elisha_Gray http://www.google.com/images - search terms “Elisha Gray” +

“Alexander Graham Bell” + “Musical telegraph” http://inventors.about.com/od/gstartinventors/a/Elisha_Gray.html http://www.oberlin.edu/external/EOG/OYTT-images/ElishaGray.html

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