Section of the mains electricity cable used to connect the Grosvenor Galleries to the Deptford substation. Made by Sebastian Ziani de Ferranti around 1890.

Sebastian Ziani de Ferranti’s design for high-voltage underground mains cables became the global standard. Existing cables could not handle the 10,000-volt current generated by Ferranti’s Deptford Power Station. Ferranti developed paper-insulated cables with conductors arranged in circles around a shared centre. Layers of waxed paper separated the outer earthed conductor from the inner live conductor.

From label attached to object: "Sample of original Ferranti cable laid in 1890 between Grosvenor Galleries (now Aeolian Hall) and Deptford substation. Cable was laid in 20 ft. lengths. There were 7,000 joints throughout the length laid. The engineer in charge was a Mr. Partridge. An article and photographs in connection with this cable was printed in The Electrical Review, March 1938."