‘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.