Carbon microphone,invented in 1878 by David Edward Hughes (1831-1900),English inventor. From R. Wormell Electricity in the Service of Man,London,1890. Engraving | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / UIG / Universal History Archive |
Taille de l’image : | 6000 px × 5532 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |