LONDON, ENGLAND - APRIL 29:  Commuters travel on the Northern Line of the London Underground which is running a limited service due to industrial action on April 29, 2014 in London, England. At 9pm last night members of the Rail, Maritime and Transport (RMT) Union commenced a 48 hour strike on the London Underground over plans to close all ticket offices with the loss of nearly 1000 jobs.  (Photo by Oli Scarff/Getty Images)