The Queen of the Savannah by Gustave Aimard

However brave a man may be it is not without a feeling of instinctive terror that he finds himself suddenly cut off from society and shut up far from the company of other men, deprived of light and almost of the vital air necessary for the due play of the lungs. Darkness brings with it sad and despairing thoughts; and however powerfully a man's character may be tempered the first moments he passes in a dungeon, whatever may be the cause that has led him there, are crushing; but, fortunately, hope is the last feeling that breaks down in a man's heart. His thoughts, constantly directed to the future, promptly recall to his heart the courage which had deserted it, and in a few hours, growing accustomed to his dungeon, he shakes off the prostration which had seized upon him, regards the position calmly, and only dreams of the means by which to regain the liberty he has lost, for that is the sole object of his thoughts, desires, and efforts.

The adventurer experienced all the feelings we have attempted to describe; but as he was an energetic man, accustomed for many years to a life of struggle, mixed up with strange episodes, he did not allow himself to be overcome by the horror of his situation, but, on the contrary, regarded it with considerable calmness and philosophy. When he had succeeded in restoring some order in his ideas, which had been upset by such rapidly succeeding events, he prepared to inspect his dungeon, which did not appear so dark as when he entered. In fact, on leaving the daylight his eyes had been at first blinded by the darkness, but they gradually grew accustomed to the obscurity, and now, though he could not see clearly, he was able to distinguish objects sufficiently to walk about without groping his way.