Electrical engineer Charles Ernest Paolo della Diana Spagnoletti was born at Brompton on 12 July 1832. His father Ernesto was a musician and his grandfather Paolo Spagnoletti was one of the leading violin players of his day. The Sardinian family, descending from the ancient noble house of Della Diana, had been forced into exile by Napoleon. In 1847 Spagnoletti started work for the Electric Telegraph Company, before joining the Great Western Railway (GWR). He made many electrical inventions. Besides signalling and telegraph equipment, he designed bells, bridges, clocks, and a fire alarm, all worked by electricity. He installed the first electric light at several London termini and advised on the use of electricity at the Crystal Palace.
In 1890 the City and South London Railway, acting on his advice, became Britain’s first electric underground railway. After leaving the GWR, Spagnoletti became managing director of the Phonophore Company, and worked on telephone development. Spagnoletti continued the musical interests of his father and grandfather. He composed many songs and had a good tenor voice. When William Preece showed the first Edison phonograph at a meeting of the Society of Telegraph Engineers in 1878, Spagnoletti sang the national anthem into it. Spagnoletti died in June 1915 at his home at no. 16 Frognal Lane, Hampstead, where he had lived for more than ten years.