In addition to the main strategy it was possible for endurance to be extended by a series of additional actions many, although not all of them, small. Together they made the difference between failure and success. Once the strike had started we concentrated on developing any means by which we could increase endurance. The need to do so became more urgent in late summer. The possibilities included increasing the output of oil-fired generating units, changing coal-fired units over to oil-firing, and recommissioning closed oil-fired power stations. Much activity and ingenuity was involved.