Go back to article: A tale of two telegraphs: Cooke and Wheatstone’s differing visions of electric telegraphy
Figure 3

© Trustees of the Science Museum Group/Science & Society Picture Library
Wheatstone’s escapement or dial telegraph (1840 specification) employed two wires for its operation and was based on the step-by-step technology. The transmitter (or communicator) can be seen on the left, the receiver (or indicator) on the right.