How can we know what to believe about a disaster as it unfolds? It all depends upon our frame of reference. When, at 8.50 am on 7 July 2005, London Underground staff at Aldgate, Edgware Road and Russell Square stations phoned their Network Control Centre (NCC) to report bomb explosions, the NCC refused to believe them for a full 27 minutes. Instead, they spoke to the media about the effects of a power surge. This was thought by some people on the Underground to be an official cover story designed to minimise panic. The fact is that the bombs led to the breaking of the track circuit and that this showed up on the NCC computer systems as a power surge because this is what had happened in 2003. See http://news.bbc.co.uk/1/hi/england/london/4674469.stm