Mark Twain has popular credit for coming up with“A lie can travel halfway around the world while the truth is still putting on its shoes” but he didn't think it up: that was Virgil in The Ænid translated by H Rushton Fairclough, he wrote "Forthwith Rumour runs through Libya's great cities, rumour of all evils the most swift, Speed lends her strength and she wins vigour as she goes, small at first, soon she mounts up to heaven and walks the ground with head hidden in the clouds." That, research shows, is exactly what happens on Twitter...