Sujet
Inventor Earl C. Hanson
Légende
United States: c. 1926
Inventor Earl C. Hanson holding the the peanut vacuum tube that he used in patenting the first vacuum tube hearing aid called the Vactuphone.
Crédit
Photo12/Underwood Archives/UIG
Notre référence
UMG20A21_439
Model release
Non
Property release
NA
Licence
Droits gérés
Format disponible
52,9Mo (7,3Mo) / 40,6cm x 32,6cm / 4800 x 3853 (300dpi)