Hadley put his head down in his hands.
`Yes. You saw the start she couldn't help giving when she saw that note on my desk. She wasn’t close enough to have read it, but the colour of the paper was enough to identify it.. if she's ever seen any similar notes in connexion with Driscoll. H'm, yes. But that's not the point. I strongly suspect that the person she was actually shadowing this afternoon was… whom do you say, Doctor?'
Dr Fell relighted his pipe. `Mrs Bitton, of course. I'm afraid she rather gave herself away, if you listened to what she said.'
But, good God!' muttered the General. `You mean to say there's something between Driscoll and.. H'm. Yes. It fits, I suppose. But where's your proof?'
`I haven't any proof. As I say, it's only a suspicion.' Hadley rubbed his chin, 'Still, let's take it as a hypothesis for the moment, and work back. Let's assume Larkin was shadowing Mrs Bitton…. Now, this White Tower, General. That's the biggest and most important one isn't it? And it's some distance away from the Bloody Tower, isn't it?'
`Well, yes… it stands alone; it's in the middle of the inner ballium walls just beside the parade-ground.'
`And the tower where the Crown jewels are kept is directly beside the Bloody Tower?'
`The Wakefield Tower. Yes. Wait a minute!' said Mason, excitedly. `I've got it. Mrs Bitton went to see the Crown Jewels. So did Larkin. Mrs Bitton said she wandered up through the arch of the Bloody Tower; and up to the parade-ground…. Larkin' went to the Bloody Tower. She couldn't keep too close to Mrs Bitton. And if she went up the stairs of the Bloody Tower to Raleigh's Walk, she could have seen from a height where Mrs Bitton was going.'
`That's what I wanted to ask you,' said Hadley, knocking his fists against his temples. `She couldn't have seen very far in the mist, of course. It's more probable she did that — if she did — to keep up the illusion of being a tourist. Or she might, have thought Mrs Bitton had gone into the Bloody Tower. It's all supposition. But neither of them went to the White Tower, you see…. Those may be coincidences, but when you couple them with the presence of those two women here, and the statements of Mrs Bitton and Larkin, they sound pretty plausible indications.'
`You're assuming,' said the General, pointing to the table, `that Mrs Bitton wrote that note?' -