The three giants rose slowly to their feet.  They uttered strange cries, and motioned with their hands toward the professor, the boys, and the others in the crowd.

“Look out!  They’re goin’ t’ grab yo’!” cried Washington.

Three of the giants approached Mark, and a like number closed in on Jack.

“Back to the ship!” cried the professor.  “We must defend ourselves!”

But by this time the big men had grabbed the two boys.  Then a strange thing took place.  Mark and Jack, though they felt that the giants must overcome them in a test of strength, struggled with all their might against being captured.  They fought, as a cornered rat will fight, though it knows the odds to be overwhelming.  But in this case the unexpected happened.

Both boys found they could easily break the holds of the giants, and Mark, by a vigorous effort, pushed the three men away from him, one at a time violently so that they fell in a heap, one on top of the other.

“Hurrah!  We can fight ’em!” cried Mark.  “Don’t be afraid.  They’re like mush!  They’re putty men!”

And, so it seemed, the giants were.  Though big in size they were flabby and had nothing like the muscle they should have had in proportion to their build.  They went down like meal sacks and were slow to rise.

Jack, seeing how successful his comrade was, attacked the three giants who were striving to make him a captive.  He succeeded in disposing of them, knocking one down so hard that the man was unable to rise until his companions helped him.

“That’s the way!” cried Washington.  “They’re soft as snow men!”

The vanquished giants set up a sort of roar, which was answered by their fellows, and soon there was a terrible din.

“All get together!” called the professor.  “They are evidently going to make a rush for us.  If we stand by one another we may fight them off, though they outnumber us a hundred to one.  Besides it will soon be dark, and we may be able to escape!”

Washington, Jack and Mark retreated toward the ship, in the direction of which the others had also made their way.  The big men had gathered in a compact mass and were advancing on the adventurers.

“What do you suppose makes them so soft?” asked Mark.  “I believe I could manage half a dozen.”

“It must be the effect of the climate and conditions here,” the professor replied.  “Probably they have to be big to stand the pressure of the thick water, and the increased attraction of gravitation.  Then too, being without the weight of the atmosphere to which we are accustomed, they have probably expanded.  If they were to go up to earth, they might shrink to our size.”

“Do you think that possible?”

“Of course.  Why do you ask?”

“Nothing in particular,” replied Mark.  But to himself, he added:  “That would explain it all.”

It was getting dusk now.  The travelers had reached their ship, and rushed inside and tried to close the doors in the face of the advancing horde.  But, by this time the giants were so close that one or two of them thrust their big feet in, and prevented this movement.  At the same time they set up a great howling.