Laying telephone cables, London, 5 November 1937.

Cros-section of a telephone cable, c 1900.

Submerged repeater (sectioned) for transatl

STC portable sound level meter, 1934.

Telephone cable damaged by fusion at Manchester, c 1900.

Telephone cable damaged by fusion at Manchester, c 1900.

Submarine telegraph cable laid across the River Medina, Isle of Wight, 1878.

Submarine telegraph cable laid across the River Medina, Isle of Wight, 1878.

Continuous wave burst set, c 1980.

Continuous wave burst set, c 1980.

Siemens telegraphic submarine cables.

Deserter marker, 1810-1850.