Even in this dungeon, where escape seemed hopeless, Rupert determined to do his best to keep life and strength together.  Nothing but the death of the king seemed likely to bring relief, and that event might be many years distant.  When it took place, his old friend would, he was sure, endeavour in every way to find out where he was confined, and to obtain his release.  At any rate he determined to live as long as he could; and he kept up his spirits by singing scraps of old songs, and his strength by such gymnastic exercises as he could carry out without the aid of any movable article.  At first he struck out his arms as if fighting, so many hundred of times; then he took to walking on his hands; and at last he loosened one of the stones which formed the top of the bed, and invented all sorts of exercises with it.

“What is the day and month?” he said one day to his gaoler.

“It is the 15th of October.”

“It is very dark,” Rupert said, “darker than usual.”

“It is raining,” the jailer said; “raining tremendously.”

Late that night Rupert was awoke by the splashing of water.  He leaped to his feet.  The cell was already a foot deep in water.

“Ha!” he exclaimed, “it is one thing or the other now.”

Rupert had been hoping for a flood; it might bring death, but he thought that it was possible that it might bring deliverance.

The top of the loophole was some two and a half feet from the vaulted roof; the top of the door was about on the same level, or some six inches lower.  The roof arched some three feet above the point whence it sprang.

Rupert had thought it all over, and concluded that it was possible, nay almost certain, that even should the water outside rise ten feet above the level of his roof, sufficient air would be pent up there to prevent the water from rising inside, and to supply him with sufficient to breathe for many hours.  He was more afraid of the effects of cold than of being drowned.  He felt that in a flood in October the water was likely to be fairly warm, and he congratulated himself that it was now, instead of in December, that he should have to pass through the ordeal.

Before commencing the struggle, he kneeled for some time in prayer on his bed, and then, with a firm heart, rose to his feet and awaited the rising of the water.  This was rapid indeed.  It was already two feet over his bed, and minute by minute it rose higher.

When it reached his chin, which it did in less than a quarter of an hour from the time when he had first awoke, he swam across to the loophole, which was now but a few inches above the water, and through which a stream of water still poured.  Impossible as it was for any human being to get through the narrow slit, an iron bar had been placed across it.  Of this Rupert took hold, and remained quiescent as the water mounted higher and higher; presently it rose above the top of the loophole, and Rupert now watched anxiously how fast it ran.  Floating on his back, and keeping a finger at the water level against the wall, he could feel that the water still rose.  It seemed to him that the rise was slower and slower, and at last his finger remained against a point in the stones for some minutes without moving.  The rise of the water inside the dungeon had ceased.