Might it not be that in their shaft sinking they had followed a vein dangerously near the old shaft?
In fact, it was not impossible that in a few hours they might not dig their way actually through into the old mine.
The thought gave Frank a deep thrill of hope.
“Barney,” he said, earnestly, “upon my soul, I believe that we are bound to make our escape.”
“Shure, Misther Frank, phwat do yez mean?” cried Barney, in surprise.
“Hush! let us wait and watch.”
For some time the two prisoners listened to the sounds of the pickaxes, and the voices of the workmen could almost be distinguished.
Suddenly, however, the sounds ceased.
All was quiet beyond the wall of earth.
What did it mean?