Editing London Waterloo station (section)

===Southern Railway===
The LSWR began to look at electrification of suburban services during the 1910s, using a 600 volt DC [[third rail]] mechanism. The first such service to Wimbledon via East Putney opened on 25 October 1915, with services to Shepperton following on 30 January 1916, the [[Hounslow Loop Line]] on 12 March and {{rws|Hampton Court}} on 18 June.{{sfn|Jackson|1984|p=232}} Ownership of Waterloo underwent a succession, broadly typical of many British stations. Under the [[Railways Act 1921|1923 Grouping]] it passed to the [[Southern Railway (UK)|Southern Railway]] (SR). The SR continued the third rail electrification of lines from Waterloo, including a full service to Guildford on 12 July 1925, and to Windsor on 6 July 1930.{{sfn|Jackson|1984|p=233}}

A [[public address system]] first ran in Waterloo on 9 March 1932, and by the following decade was regularly broadcasting music around the station.{{sfn|Jackson|1984|p=235}} In 1934, the SR planned to invest £500,000 (£{{inflation|UK|0.5|1934}} million as of {{inflation-year|UK}}) to improve the signalling and track layout to allow better use of all platforms.{{sfn|Jackson|1984|pp=233–234}} A full electric service to Woking, Guildford and {{rws|Portsmouth Harbour}} (for the [[Isle of Wight]]) opened on 4 July 1937, as did connecting services to {{rws|Aldershot}} and {{rws|Alton}}. On 1 January 1939 an electric service opened between Waterloo and Reading, with a branch to {{rws|Camberley}} and Aldershot, which was designed equally for the anticipated increase in military traffic in the area as well as commuters.{{sfn|Jackson|1984|p=235}}

Waterloo was bombed several times during [[World War II]]. On 7 September 1940, the John Street viaduct immediately outside the station was destroyed by a bomb, which prevented any services running for 12 days. Full services did not resume until 1 October, which particularly affected mail traffic with over 5,000 unsorted bags piling up on the station platform. Waterloo was closed again after bombing on 29 December 1940. It re-opened on 5 January 1941, on the same day that station offices on York Road were destroyed by bombing. The station took heavy damage again after an overnight raid on 10–11 May 1941, with fires lasting for four days.{{sfn|Jackson|1984|p=236}} One {{convert|2000|lb|adj=on}} bomb was not discovered until it was uncovered during building work along York Road in 1959.{{sfn|Jackson|1984|p=237}}