An authenticated Edison letter's value depends on the rarity, condition, and content. Also whether it is typed or holographic, in his own handwriting. His classic "umbrella" signature alone can be worth $500 or more. Letters start closer to $1000 and can be many times that. Ultimately, the final value is determined by what someone is willing to pay
Submarine telegraph has written: 'The story of my life'
Edward Highton has written: 'The electric telegraph' -- subject(s): Telegraph, History
Chetwode Crawley has written: 'From telegraphy to television' -- subject(s): Television, Telegraph, Wireless, Radio, Telegraph, Telephone, Wireless Telegraph
Joseph S. Rich has written: 'Some notes on the telegraph companies of the United States' -- subject(s): Telegraph stamps, Telegraph
David Hochfelder has written: 'The telegraph in America, 1832-1920' -- subject(s): Telegraph, History
S. Guy Lawrence has written: '40 years on the Yukon telegraph' -- subject(s): Telegraph
Louis Casper has written: 'Telephone and telegraph cables' -- subject(s): Telegraph cables, Telephone cables
hand written letters
Cyril Methodius Jansky has written: 'Principles of radiotelegraphy' -- subject(s): Telegraph, Wireless, Wireless Telegraph
Alonzo B. Cornell has written: 'History of the electro-magnetic telegraph' -- subject- s -: Telegraph, History '\\'
A. E. Loring has written: 'A hand-book of the electromagnetic telegraph' -- subject(s): Accessible book, Operators' manuals, Telegraph
Lester G. Lindley has written: 'The impact of the telegraph on contract law' -- subject(s): Employers' liability, History, Law and legislation, Liability (Law), Social aspects of Telegraph, Telegraph