Dumoulin Walnut Intercom
American Magnetic Electric intercom
1888

Speaking tube intercom telephone

About This Phone

Circa 1880. This is a Speaking Tube Telephone designed to work on a Commercial Intercom System within an office or plant. Speaking Tube Systems enabled any user to act as an Attendant, and each could speak with all other users on the system. We can tell, by how this unit is configured, that it was used on a system with 12 similar instruments.

Related PDFs

American Bell Telephone Annual Report, 1881
American Bell Telephone Annual Report, 1881
1881
 American Bell Telephone Annual Report, 1882
American Bell Telephone Annual Report, 1882
1882
 American Bell Telephone Annual Report, 1884
American Bell Telephone Annual Report, 1884
1884
 American Bell Telephone Annual Report, 1885
American Bell Telephone Annual Report, 1885
1885
 American Bell Telephone Annual Report, 1887
American Bell Telephone Annual Report, 1887
1887
 American Bell Telephone Annual Report, 1889
American Bell Telephone Annual Report, 1889
1889