The question that brought the House down concerned the 60 million rats in Britain and rehashed the fact that Londoners are never more than nine metres from one. Mr Blair didn't know that, he said, but he does know that in this chamber the gap is never more than nine inches. He also knows, to his relief and joy, that the Westminster rat has a gratifying habit of clambering back aboard a ship that, having flirted with a capsize, has been successfully refloated.