ScientificAmerican1894-02-03.jpg Radio Digest 1932-01ThumbnailsScientific American 1894-11-24Radio Digest 1932-01ThumbnailsScientific American 1894-11-24Radio Digest 1932-01ThumbnailsScientific American 1894-11-24Radio Digest 1932-01ThumbnailsScientific American 1894-11-24Radio Digest 1932-01ThumbnailsScientific American 1894-11-24
Details of construction of the Bell telephone. Single wire circuit. Metallic circuit.



Source: Steve Kirch, collector, and creator of a great website about SCIENTIFIC AMERICAN in the past

Restoration by: magscanner