“I have a plan to get rid of these rough men,” the mate said to Mark.  “It may work, and, again it may not.  At any rate it is worth trying, It all depends on you with what help I can give you.”

“I’m willing to do my share,” Mark said, and for the next ten minutes the boy and the mate were in earnest conversation.

It was about thirty-five minutes later when there arose a sudden commotion in the ship.  Mark had returned to his friends and the mate had disappeared.  The confusion seemed to come from the engine room where Tony had posted some of his men.

“We’re falling down!  We’ll all be killed!” shouted the men.  “The ship is falling into the sea!”

“What is the trouble?” asked the professor as he heard the commotion.

“It is part of the mate’s plan,” said Mark.  “He told me to tell you to do nothing.  If Tony or any of the other men come to you just refer them to me.”

Two minutes later Tony came rushing into the apartment where the captives were held prisoners.

“Here!  Come quickly, Mark!” he exclaimed.  “Something has gone wrong with the gas machine again, and you must come and fix it before we are all dashed to pieces!”

With every appearance of haste Mark rushed from the apartment, following Tony.  The latter led the way to the engine room.

“Can anything be done?” he asked.

Mark took a survey of the machinery.

“It is too late,” he said as though much excited.  “The ship is falling down toward the sea with terrific force.”

It needed but a glance at the height gage to show this.  The pointer was revolving rapidly about the face of the dial.

“Will the ship stand the blow?” asked Tony.

“Not at the rate it is falling,” replied Mark.  “She will go all to pieces when she strikes the water, and she may explode!”

“What are we to do then?” asked the leader of the mutineers.

“We must save ourselves!” cried the mate, running in at this juncture.  “Let our prisoners shift for themselves as best they can.  Let’s all leap into the sea.  There we at least have a chance for our lives.  But if we stay on this ship we will all be drowned like cats in a bag.”

“What do you propose?” asked Tony, his face white with fear.

“When the ship comes near enough the surface of the water to make it safe we should all drop overboard!” the mate exclaimed.  “We are near some islands, I understand, and we can thus save our lives by swimming ashore.”

This plan seemed to meet with instant favor, and a little later there was a rush for the deck, as each one wished to be the first to escape from the boat they believed to be doomed.

Lower and lower fell the Mermaid.  She was like a wounded bird which the shot of the hunter has crippled.  Down and down she fluttered.

By this time all the sailors, save the mate were on deck.  He and Mark remained in the engine room.