advised, the inventor himself stretching out at full
length. A little relief was experienced.

They knew it could not last long. Even the professor seemed to have
given up hope. The engine was not going to free the ship in time to save
the lives of those on board.

Washington crawled to the engine room, as some of the bearings needed
oiling. The professor seemed in despair. He opened one of the slides
that covered the glass bulls eye windows. Then he turned off the
electric lights. The opening was black, showing that the sea of grass
still surrounded them. With a groan Mr. Henderson turned aside. The last
hope was gone. He sank down on the floor of the darkened cabin.

Just then Mark happened to look at the bull's-eye. He saw a glimmer of
light. Then he noticed several fishes swimming about. The water was
clear. The grass had disappeared from the vicinity of the window.

"Look!" cried Mark to the professor.

The inventor peered forth. As he did so he uttered a cry. Then he
staggered rather than ran to the engine room.

"What are you doing?" he called to Washington.

"I jest let some ob de sulphuric acid out ob de storage battery tank,"
replied the colored man.

"That's it! That's it!" exclaimed the professor. "Quick, let some more
out, Washington. Let out all there is in that tank. It will save our
lives."

Wonderingly Washington obeyed. The air in the ship was growing more foul
every second. It was hard to breathe even on the floor, and all were
gasping for breath. A few minutes more and they would all become
unconscious and death would come in a little while if the air was not
freshened.

The professor staggered back to the main cabin. He looked out of the
bull's-eye windows. Then he exclaimed:

"See, it is getting lighter! Thank Heaven we are saved!"

The next instant the ship began to move backward. Then with increasing
speed it pulled out of the grip of the long grass, and in another minute
was floating on top of the water, at the edge of the Sargasso Sea.

"Quick! Open the man hole cover!" said Amos Henderson.

Washington threw back the lever cams, and in rushed the fresh air. It
was a blessed relief from the terrible oppressiveness of the foul
atmosphere of the boat. They all breathed deeply, and, in a few minutes
the effects of their long imprisonment had passed off.

They went out on the small deck. It was getting dusk, and the reflection
of the red sunset shone brightly on the heaving water.