Commuters brave the rush hour on the northern line on the London underground in London, Britain August 5, 2015. Londoners face major transport disruption from Wednesday evening as train drivers and staff on the underground rail network walk out for the second time in less than a month. Unions are angry over plans to introduce a new night service from September and weeks of talks with transport bosses have failed to clinch a deal over pay and conditions. REUTERS/Dylan Martinez TPX IMAGES OF THE DAY