Storri was especially struck by the fact that a considerable stream of water gushed from the drain's mouth; the stream had a fair current, four miles an hour at least, and showed a depth of full six inches.

This was a discovery that set Storri's wits in motion; the drain boxed in a living brook.
It was eleven o'clock that night when Storri returned to the mouth of the drain; he was wrapped in a greatcoat and wore high boots.

There were no houses about; as for loiterers, the region was deserted after dark.

Storri looked out on the broad bosom of the river; he noticed that even at low tide a boat drawing no more than eighteen inches might push within a dozen feet of the drain.
Satisfied that no one observed him, Storri stepped to the mouth of the drain and disappeared.

He splashed along in the running water with his heavy boots for something like a rod; then he stopped and lighted a bicycle lantern which he took from his greatcoat pocket.