There were probably vaults beneath this courtyard, and this stone concealed the entrance to them.
Animated by this fresh hope, the party now worked away, and in a few minutes had lifted the ponderous flagstone.
A flight of rude steps, leading down into utter darkness, was discovered.
"As I thought," cried Jack, "these are vaults; we may baffle them after all. Bogey, run down immediately and see what they are like."
Bogey hesitated not a moment, but skipped down the rude steps and disappeared.
The others waited his return with great anxiety.
At this moment, a shout of triumph was raised by their enemies outside.
It signified that the cannon had been brought, and that the attack would soon recommence.
The hope of escape was still of the very slightest.
In a few moments Bogey returned.