“The main thing with people of that sort,” said Holmes, as we sat in the sheets of the wherry, “is never to let them think that their information can be of the slightest importance to you. If you do, they will instantly shut up like an oyster. If you listen to them under protest, as it were, you are very likely to get what you want.”

“Our course now seems pretty clear,” said I.

“What would you do, then?”

“I would engage a launch and go down the river on the track of the Aurora .”

“My dear fellow, it would be a colossal task. She may have touched at any wharf on either side of the stream between here and Greenwich. Below the bridge there is a perfect labyrinth of landing-places for miles. It would take you days and days to exhaust them, if you set about it alone.”