The Maderia quivered from stem to stern, seemed to hesitate a moment as though she had been brought to a sudden stop, and then plowed on, only to bring up against some obstruction again, with that same sickening jar throughout her length.

“Bless my soul!  What’s that?” cried Mr. Damon, springing from his berth.

“Something has happened!” added Tom, as he reached out and switched on the electric lights.

“We hit something!” declared Ned.

The ship was now almost stopped and she was rolling from side to side.

Up on deck could be heard confused shouts and the running to and fro of many feet.  The jangling of bells sounded—­hoarse orders were shouted—­and there arose a subdued hubbub in the interior of the ship.

“Something sure is wrong!” cried Tom.  “We’d better get our clothes on and get on deck!  Come on, Ned and Mr. Damon!  Grab life preservers!”

CHAPTER XII

INTO THE UNKNOWN

“Bless my overshoes!  I hope we’re not sinking!” cried Mr. Damon, as he struggled into some of his clothes, an example followed by Ned and Tom.

“This boat has water-tight compartments, and if it does sink it won’t do it in a hurry,” commented Tom.

“I don’t care to have it do it at all,” declared Ned, who found that he had started to get into his trousers hindside before and he had to change them.  “Think of all our baggage and supplies and the balloon on board.”  For the travelers had shipped their things by the same steamer as that on which they sailed.

“Well, let’s get out and learn the worst,” cried Tom.

He was the first to have the stateroom, and as he rushed along the passages which were now brilliant with light he saw other half-clad passengers bent on the same errand as himself, to get on deck and learn what had happened.

“Wait, Tom!” called Ned.

“Come along, I’m just ahead of you,” yelled his chum from around a corner.  “I’m going to see if Eradicate is up.  He’s an awful heavy sleeper.”

“Bless my feather bed!  That shock was enough to awaken anyone!” commented Mr. Damon, as he followed Ned, who was running to catch up to Tom.

Suddenly a thought came to our hero.  The mysterious passengers in Stateroom No. 27!  Surely this midnight alarm would bring them out, and he might have a chance to see who they were.

Tom thought quickly.  He could take a turn, go through a short passage, and run past the room of the mysterious passengers getting on deck as quickly as if he went the usual way.

“I’ll go look after Rad!” Tom shouted to Ned.  “You go up on deck, and I’ll join you.”

Eradicate’s stateroom was on his way, after he had passed No. 27.  Tom at once put his plan into execution.  As he ran on, the confusion on deck seemed to increase, but the lad noted that the vessel did not pitch and roll so much, and she seemed to be on an even keel, and in no immediate danger of going down.