It was the mine underneath the North Tower which brought the career of
Luffe to an end. The garrison, indeed, had lived in fear of this peril
ever since the siege began. But inasmuch as no attempt to mine had been
made during the first month, the fear had grown dim. It was revived
during the fifth week. The officers were at mess at nine o'clock in the
evening, when a havildar of Sikhs burst into the courtyard with the news
that the sound of a pick could be heard from the chamber of the tower.

"At last!" cried Dewes, springing to his feet. The six men hurried to the
tower. A long loophole had been fashioned in the thick wall on a downward
slant, so that a marksman might command anyone who crept forward to fire
the fort. Against this loophole Luffe leaned his ear.

"Do you hear anything, sir?" asked a subaltern of the Sappers who was
attached to the force.

"Hush!" said Luffe.

He listened, and he heard quite clearly underneath the ground below him
the dull shock of a pickaxe. The noise came almost from beneath his feet;
so near the mine had been already driven to the walls. The strokes fell
with the regularity of the ticking of a clock. But at times the sound
changed in character. The muffled thud of the pick upon earth became a
clang as it struck upon stone.

"Do you listen!" said Luffe, giving way to Dewes, and Dewes in his turn
leaned his ear against the loophole.

"What do you think?" asked Luffe.