‘None. Now here, sir, we have a bit of evidence that is new to you. I feel sure that if you’d had it earlier today it would have made a difference to your view of the case. We have found out that within a few hours of the murder, a bottle of iodine disappeared from the bathroom cupboard upstairs.’

Colonel Brammington stared a little wildly at Alleyn, made as if to speak, and evidently thought better of it. He waved his hand.

‘The bottle of iodine that was originally in the downstairs first-aid box,’ Alleyn continued, ‘was an entirely innocent bottle, with Abel’s prints on it and only his. Legge’s prints were added when he borrowed this bottle to doctor a cut on his chin. Abel gave it to him. Now that innocent and original bottle is, I consider, the one that was found under the settle. All that is left of the bottle Abel Pomeroy used when he poured iodine into Watchman’s wound, is represented, or so we believe, by the surplus amount of glass Mr Harper swept up from the floor and by the small misshapen fragments we found in the ashes.’

‘Hah!’ ejaculated the colonel. ‘Now I have you. A lethal bottle, taken from the bathroom and infected, was substituted for the innocent bottle in the first-aid box. Only Abel Pomeroy’s prints were found on the cupboard door and so on. Abel Pomeroy himself took the bottle from the box and himself poured the iodine into the wound. Splendid!’

‘Exactly, sir,’ said Alleyn.

‘Well, Alleyn, I readily abandon my second love. I return, chastened, to my first love. How will you prove it?’

‘How indeed! We hope that an expert will be able to tell us that the fragments of glass are, in fact, of the same type as that used for iodine bottles. That’s not much but it’s something and we have got other strings to our bow.’

‘What’s his motive?’

‘Whose motive, sir?’

‘Old Pomeroy’s.’

Alleyn looked at him apologetically.

‘I’m sorry, sir. I hadn’t followed you. Abel Pomeroy had no motive, as far as I know, for wishing Watchman dead.’

‘What the hell d’you mean?’

‘I didn’t think Abel Pomeroy was strictly your first love, sir. May I go on? You see, once we accept the iodine theory, we must admit that the murderer knew Watchman would be wounded by the dart. Nobody knew that, sir, but Legge.’

II

It took the second half of the last bottle of Treble Extra to mollify the chief constable, but he was mollified in the end.