moon that had lately risen.

Washington gave one frightened, startled look, and then, with a tongue
that could hardly move, he yelled out:

"De ghost! De ghost! He'll git me suah!"

Then the colored man made a dive for the stairway leading to the cabin,
but missed it and brought up with a crash on the steel floor of the
conning tower.

"What is it?" called Professor Henderson, springing out of his bunk.

"De ghost!" wailed Washington from the huddled up heap he was in.

"Catch him!" yelled the captain.

"I dasn't," moaned Washington.

The next instant the ship quivered from stem to stern. There was a
terrible shock, followed by a grinding, crashing sound. Then the craft
seemed to be pressed down by some great weight. It heeled over to one
side, and the water began to pour down the open man-hole.

"Quick! Clamp on the covers!" shouted Mr. Henderson as he felt the sea
dashing into the interior of the boat.

Jack and Mark sprang to obey. It took all their strength, for the water
was running in like a mill-race.

"What has happened?" asked Andy, as he tried to climb up the
companionway ladder, that was tilted backward.

"I guess we've hit your iceberg!" cried Mr. Henderson.

"I knew I smelled the frozen stuff," replied the old hunter.

They got the covers on the manhole only just in time and they all
crowded into the cabin, while Jack switched on the electric lights.

"Is the ship damaged?" asked Mark.

"I think not," replied Mr. Henderson. "But we are sinking. Look at the
depth gage."

The hand on the clock-face was moving slowly around. From ten it went to
twenty feet, then to thirty and kept going until it stood at seventy.

"Look to the air tanks," ordered Mr. Henderson to Washington, who, by
this time had recovered from his fright. "See if they are all right."

The colored man came back in a few minutes and reported that the supply
of compressed atmosphere was safe and that there was plenty of it.

"That's good," remarked Mr. Henderson. "Whatever else happens we can
breathe for a while."

"But what has happened?" asked Andy.

"I think the top part of an iceberg toppled down on us," was the reply.
"You know about nine-tenths of a berg is under water. Sometimes there is
a warm current of the ocean underneath the ice, and it melts. Then it
becomes top-heavy and tilts over. One of that sort must have caught us,
and has shoved us down into the sea."

"But why don't we rise again when the ice floe