“Whew!” whistled Bert, looking at the big, stuffed fellow.  “He could swim around with two or three boys on his back.”

“I’d like to have had a ride on him,” cried Freddie.  “But this one is pretty big, too!” and he pointed down at the large swimming turtle, which, just then, stuck his head up out of the water.  He seemed to be nearly a yard long and almost as broad.

“Oh!” screamed Flossie, as she saw the big turtle so close to her.  “Can he get out of the water, Daddy?”

“No, indeed,” laughed Mr. Bobbsey.

“I can’t see him very good,” said Freddie, and he gave a little jump up from the foot-rail on which he was standing.

Freddie must have jumped up harder and farther than he had any idea of, for before Bert, who was standing near his little brother, could put out a hand to hold him, the flaxen-haired twin had fairly dived over the rail, and down into the tank he fell with a great splash.

No, not such a great splash, either, for Freddie did not fall directly into the water.  Instead, only his two fat legs and feet went in, for the small boy landed, sitting right up on the broad back of the big turtle!  Right down on the turtle’s back fell Freddie Bobbsey!

CHAPTER XII

IN THE THEATRE

There was a scream from Nan, another from Flossie, and a sort of grunt of surprise from Bert, as they saw Freddie disappear over the railing of the tank, and come into view a second later on the back of the turtle, which was as much surprised as, probably, the little boy himself.

“Here, Freddie!  What are you doing down there?” asked Mr. Bobbsey, before he thought what he was saying.  He and his wife had so often to ask what Flossie or Freddie were doing, as the smaller twins were so often in mischief, that the father did it this time.

“Oh, the turtle will eat him up!  The turtle will eat Freddie up!” cried Flossie.

Freddie, too, after the first shock of surprise, was frightened, and as he clung with both hands to the edges of the turtle’s shell he looked over his shoulder, toward his father and the others, and cried: 

“Oh, get me out, Daddy!  Get me out!”

The cries of the children, and the call of Mr. Bobbsey, had drawn a crowd around the turtle pool, and among the throng were some of the attendants on duty in the Aquarium.

“What’s the matter?” asked one, elbowing his way through the crowd to the side of Mr. Bobbsey, who was trying to climb over the rail to go to the rescue of his little boy.

[Illustration:  “FREDDIE FELL IN!” “HE’S ON THE BACK OF A BIG TURTLE.” The Bobbsey Twins in a Great City.  Page 128]

“Freddie fell in,” explained Bert.  “He’s on the back of the big turtle!”

“Good land!” cried the man.  “What will happen here next?  Come back, sir,” he went on to Mr. Bobbsey, “I’ll get him out for you.”