It was a thousand times more so than he had expected; he discovered this almost immediately.
It was the first time that he had ever worked with a file, and he did not know how to use it.

His progress was despairingly slow.
Nor was that all.

Though he worked as cautiously as possible, each movement of the instrument across the iron produced a harsh, grating sound that froze his blood with terror.

What if someone should overhear this noise?
And it seemed to him impossible for it to escape notice, since he could plainly distinguish the measured tread of the guards, who had resumed their watch in the corridor.
So slight was the result of his labors, that at the end of twenty minutes he experienced a feeling of profound discouragement.
At this rate, it would be impossible for him to sever the first bar before daybreak, What, then, was the use of spending his time in fruitless labor?
Why mar the dignity of death by the disgrace of an unsuccessful effort to escape?
He was hesitating when footsteps approached his cell.

He hastened to seat himself at the table.
The door opened and a soldier entered, to whom an officer who did not cross the threshold remarked: "You have your instructions, Corporal, keep a close watch.