The Telephone’s sesquicentennial

From harmonic telegraph to wearable technology

by Nigel Linge, Andy Sutton, Neil Johannessen, Andy Simmons, and Andrew Hurley

The 14th of February 2026 was an important sesquicentennial anniversary for telecommunications because it was on that day in 1876, 150 years ago, that Alexander Graham Bell submitted his patent for what became the telephone. Since then, the telephone has undergone a metamorphosis that has transformed it from something akin to a piece of furniture to a software app. Today, telephony has become a service that can be accessed using a smartphone, tablet, smart watch, virtual reality headset, or a traditional telephone. In this paper we celebrate the telephone’s amazing story with a specific focus on civilian and military life.

We start by reviewing Bell’s background and motivations, from his early fascination with speech and sound to his move from Scotland to Canada and then to Boston, where he tutored deaf students. Bell’s experiments with the “harmonic telegraph” and a key observation with assistant Thomas Watson led to an early “gallows” telephone design using a vibrating reed near an electromagnet. Bell’s patent application, titled “Improvement in Telegraphy,” did not use the word “telephone,” yet envisaged transmitting voice and music. However, as discussed, that patent courts controversy to this very day.

Thereafter, the paper describes how the telephone made its way to the UK in 1878. Turning to technology and everyday use, it charts the shift from battery-powered wall sets and operator-assisted calling to central-battery systems and automated switching (Strowger), followed by interwar and postwar expansion, mass-produced Bakelite and plastic telephones, electronic and then digital switching, and the transition from radio telephones to the mobile, cellular, smartphone.

As a parallel track, the paper explores military usage in terms of the field telephone which evolved as armies adapted voice communication to harsh battlefield conditions. Early use in the late 1800s relied on modified civilian phones connected by exposed wires, trialled in conflicts such as the Franco Prussian War. Their decisive role emerged in the First World War, where static trench warfare demanded reliable links. Between wars, designs became more portable and rugged and by the Second World War, sets like Britain’s Telephone Set D and L supported larger switched networks. Radios later dominated, but wired phones remained valuable against jamming and interception.

Finally, with all the advances that have been made over the previous 150 years, the future still remains bright for it must always be remembered that it’s not the telephone that does the talking, but people!

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