But at this moment there was a faint whistle from the tow-path. A similar whistle answered from the boat. Two other signals were exchanged at regular intervals.
A church clock struck midnight.
"It's an appointment," Paul conjectured. "This is becoming interesting. Follow me. I noticed a place below where I think we shall be safe against any surprise."
It was a back-cellar separated from the first by a brick wall containing a breach through which they easily made their way. They rapidly filled up the breach with bricks that had fallen from the ceiling and the walls.
They had hardly finished when a sound of steps was heard overhead and some words in German reached their ears. The troop of soldiers seemed to be fairly numerous. Bernard fixed the barrel of his rifle in one of the loop-holes in their barricade.
"What are you doing?" asked Paul.
"Making ready for them if they come. We can sustain a regular siege here."
"Don't be a fool, Bernard. Listen. Perhaps we shall be able to catch a few words."
"You may, perhaps. I don't know a syllable of German. . . ."
A dazzling light suddenly filled the cellar. A soldier came down the ladder and hung a large electric lamp to a hook in the wall. He was joined by a dozen men; and the two brothers-in-law at once perceived that they had come to remove the dead.