The legend goes that it was the late great Irish music journalist, Bill Graham, who told the late, great Island press officer, Rob Partridge, that U2 were going to be bigger than Thin Lizzy. So it was that Partridge dragged Chris Blackwell away from the Crystal Palace Bowl on a Saturday night in July 1980, where Bob Marley and the Wailers had just mesmerised fifty thousand people, to a south London pub, the Half Moon in Herne Hill, where U2 were struggling to keep the attention of about fifty punters. These are the photographs.