‘Could a barrel be changed, or completely emptied and filled with something else?’ ‘It could not. The thing’s altogether impossible.’ ‘I’m much obliged to you, captain. Good-day.’ Inspector Burnley was nothing if not thorough. He questioned in turn the winch drivers, the engineers, even the cook, and before six o’clock had interviewed every man that had sailed on the _Bullfinch_ from Rouen. The results were unfortunately entirely negative. No information about the cask was forthcoming. No question had been raised about it. Nothing had happened to call attention to it, or that was in any way out of the common. Puzzled but not disheartened, Inspector Burnley drove back to Scotland Yard, his mind full of the mysterious happenings, and his pocket-book stored with all kinds of facts about the _Bullfinch_, her cargo, and crew. Two messages were waiting for him. The first was from Ralston, the plain-clothes man that he had sent from the docks in a northerly direction. It read:-- ‘Traced parties as far as north end of Leman Street. Trail lost there.’ The second was from a police station in Upper Head Street:-- ‘Parties seen turning from Great Eastern Street into Curtain Road about 1.20 p.m.’ ‘H’m, going north-west, are they?’ mused the Inspector taking down a large scale map of the district. ‘Let’s see. Here’s Leman Street. That is, say, due north from St. Katherine’s Docks, and half a mile or more away. Now, what’s the other one?’--he referred to the wire--‘Curtain Road should be somewhere here. Yes, here it is. Just a continuation of the same line, only more west, say, a mile and a half from the docks. So they’re going straight, are they, and using the main streets. H’m. H’m. Now I wonder where they’re heading to. Let’s see.’ The Inspector pondered. ‘Ah, well,’ he murmured at last, ‘we must wait till to-morrow,’ and, sending instructions recalling his two plain-clothes assistants, he went home. But his day’s work was not done. Hardly had he finished his meal and lit one of the strong, black cigars he favoured, when he was summoned back to Scotland Yard. There waiting for him was Broughton, and with him the tall, heavy-jawed foreman, Harkness. The Inspector pulled forward two chairs. ‘Sit down, gentlemen,’ he said, when the clerk had introduced his companion, ‘and let me hear your story.’ ‘You’ll be surprised to see me so soon again, Mr. Burnley,’ answered Broughton, ‘but, after leaving you, I went back to the office to see if there were any instructions for me, and found our friend here had just turned up. He was asking for the chief, Mr. Avery, but he had gone home. Then he told me his adventures, and as I felt sure Mr. Avery would have sent him to you, I thought my best plan was to bring him along without delay.’ ‘And right you were, Mr. Broughton. Now, Mr. Harkness, I would be obliged if you would tell me what happened to you.’ The foreman settled himself comfortably in his chair.