The gate opened.

He drew it close after him, but did not lock it, so as to avoid delay on his return.

The crowbar he left at the corner of the gate.
Then, with straining ears, dilated pupils, every sense tense with this effort to hear, the need to breathe, the impossibility of seeing, he advanced slowly, a pistol in one hand, touching the wall with the other to guide himself.

He walked thus for fifteen minutes.

A few drops of ice-cold water fell through the roof on his hands and shoulders, and told him he was passing under the river.
At the end of this time he found the door which opened from the passage into the quarry.