Herrmann Wall Phone

The Herrmann wall phone was a type of telephone, created by the Portuguese inventor, Maximiliano Augusto Herrmann, in 1880. The pioneering use of buttons to activate the telephone played a fundamental role to the opening of public lines in the main cities of Portugal.[1] The telephone was composed by a double earpiece, made with long flexible tubes, and a transmitter fixed to main body of the machine.

Wall telephone developed by Herrmann as part of the Communication Museum in Lisbon.

Its inventor, Maximiliano Augusto Herrmann, worked for the North and East Portuguese Railway Company (Portuguese: Companhia dos Caminhos-de-ferro do Norte e Leste) as telegraph lines inspector. He later opened a workshop dedicated to the production of precision instruments.