Improving the telephone . . .
One of the innovations which has somehow survived, is an example of the telephone, originally invented by Alexander Graham Bell and which Trouvé improved in 1878.
Each piece measures 17 cm long by 8cm in diameter and is in the collection of a Monsieur Alain Groult, the President of the National Association of Telephone Collectors in France.
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Is this the great-great grandpa of the mobile phone?