The Magnetc Telegraph Company Links Britain and Ireland via Submarine Telegraph Cable

The British and Irish Magnetic Telegraph Company (also called the Magnetic Telegraph Company or the Magnetic) was founded by John Brett in 1850. The Magnetic was the principal competitor to the largest telegraph company in the United Kingdom, the Electric Telegraph Company (the Electric). The Magnetic was the leading company in Ireland, while the Electric was the leading company in mainland Britain. Between them, they dominated the market until the telegraph was nationalised in 1870.

The Magnetic’s telegraph system differed from other telegraph companies. They favoured underground cables rather than wires suspended on poles. This system was problematic because of the limitations of insulation materials available at the time, but the Magnetic was constrained by the wayleaves owned by other companies on better routes. They were also unique in not using batteries which were required on other systems. Instead the operator generated the necessary power electromagnetically. The coded message was sent by the operator moving handles which moved coils past a permanent magnet thus generating telegraph pulses.