Bill and Tom were so alarmed that they were of little use in doing anything, and they were not disturbed in their staterooms where they went when it became known that the ship was unmanageable.

The boys and the professor, while greatly frightened at the unexpected turn of events, decided there was no use in giving way to foolish alarm.  They realized they could do nothing but await developments.

At the same time they took every precaution.  They piled all the bedding on the floor of the living room, so that the pillows and mattresses might form a sort of pad in case the ship was dashed down on the bottom of the big hole.

“Not that it would save us much,” Jack observed with a grim smile, “but somehow it sort of makes your mind easier.”

All this while the ship was being sucked down at a swift pace.  The pointer of the gage, indicating the depth, kept moving around and soon they were several hundreds of miles below the surface of the earth.

The professor tried, by means of several instruments, to discover in which direction they were headed, and whether they were going straight down or at an angle.  But some strange influence seemed to affect the gages and other pieces of apparatus, for the pointers and hands would swing in all directions, at one time indicating that they were going down, and, again, upward.

“There must be a strong current of electricity here,” Mr. Henderson said, “or else there is, as many suspect, a powerful magnet at the center of the earth, which we are nearing.”

“What will you do if the ship is pulled apart, or falls and is smashed?” asked Mark with much anxiety.

“You take a cheerful view of things,” said Jack.

“Well, it’s a good thing to prepare for emergencies,” Mark added.

“If the ship was to be separated by the magnetic pull, or if it fell on sharp rocks and was split in twain, I am afraid none of us could do anything to save ourselves,” the professor answered.  “Still, if we were given a little warning of the disaster, I have means at hand whereby we might escape with our lives.  But it would be a perilous way of——­”

“I reckon yo’ all better come out an’ have supper,” broke in Washington.  “Leastways we’ll call it supper, though I don’t rightly know whether it’s night or mornin’.  Anyhow I’ve got a meal ready.”

“I don’t suppose any of us feel much like eating,” observed Mr. Henderson, “but there is no telling when we will have the chance again, so, perhaps, we had better take advantage of it.”

For a while they ate in silence, finding that they had better appetites than they at first thought.  Old Andy in particular did full justice to the food Washington had prepared.

“I always found it a good plan to eat as much and as often as you can,” the hunter remarked.  “This is a mighty uncertain world.”

“You started to tell us a little while ago, Professor,” said Mark, “about a plan you had for saving out lives if worst came to worst, and there was a chance to put it into operation.  What is it?”