Fax machine

A fax machine sends copies of documents over a wire. It is usually thought of as a gadget of the 1980s, but the first fax machine was patented in 1843 by Alexander Bain, a Scottish clockmaker, more than thirty years before Alexander Graham Bell patented the telephone in 1876.^[1] For several decades, therefore, it was possible in principle to fax someone but not to ring them to ask whether it had come through.

Pendulums

Bain's device used two synchronised clock pendulums, one at each end of a telegraph wire, swinging in step. A stylus on the sending pendulum passed over raised metal type, and the matching pendulum at the receiving end marked chemically treated paper whenever the circuit was closed.^[2] It was, in effect, two clocks agreeing with each other about a letter.

In the 1860s an Italian inventor, Giovanni Caselli, built the pantelegraph, which was used for a commercial fax service between Paris and Lyon from 1865. Users mostly sent signatures and short handwritten messages, and nobody sent a cover sheet.

Lifespan

Fax machines became common in offices in the 1980s, more than 140 years after Bain's patent, and remain in use in some offices, hospitals and government departments today. The fax machine is therefore older than the telephone, the light bulb and the car, and has outlived the pager, which arrived more than a century later.

• Fax machine: 1843.
• Telephone: 1876.
• Fax machine in every office: 1980s.
• Confirmation that it was received: still pending.

See also

• Printing press – another way of copying
• Hour – clocks were involved
• Traffic light – another invention older than expected
• Transatlantic telegraph cable – an earlier way to send a message across the sea

References

1. Pendulum, P. (1843/2001). Two Clocks Agreeing. Fictional reprint.
2. Telegraph, T. (2007). “Before the Telephone”. Communications History 1843: 1.
3. Received, R. (1989). Did You Get My Fax? Office Press.