There were some very large turtles in the tank, swimming by moving their broad flippers. Sometimes they would swim about close to the white tiled bottom of the tank, but the water was clear, so they could be seen easily.

Again the turtles would rise to the top, so that their big, hard sh.e.l.ls were out of water, like a raft which the boys build to play with when the city's vacant lots or country meadows are flooded in the Spring.

In one end of the tank was a big turtle--the largest of all--swimming by himself, and overhead, hung by a wire from the room, was a stuffed one, larger yet. This, so a sign near it said, was a "leather-back turtle," and when alive had weighed eight hundred and fifty pounds.

"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 sh.e.l.l 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.

[Ill.u.s.tration: "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."

"Then please be quick. He may fall off and the turtle may bite him or drown him," said Freddie's father.

"Well, the turtle _could_ give him a bad bite," returned the Aquarium man.

"But if he holds on a little longer I'll get your boy."

The man jumped up on the ledge of the pool and made his way to the piece of wood that held up the heavy wire screen which divided the turtle pool into two parts, keeping the one big turtle away from the others. All this while Freddie sat on the sh.e.l.l of the big turtle, his chubby legs dangling in the water, and his hands grasping the edges of the sh.e.l.l behind the front flippers. The turtle's neck was so short that it could not turn its head to bite Freddie, nor could the big flippers reach him. As they had no claws on the ends, they would have done no harm, anyhow, if they had brushed him.

The greatest danger was that the turtle might suddenly sink down to the bottom of the pool, and, though it was not very deep, it was deep enough to have let Freddie drown.

Even though the small boy could swim, the turtle might attack him, or knock his head under water, which would have been a great danger to Flossie's brother. But, so far, the turtle did not show any wish to sink below the water. It was frightened, that was certain, for it splashed about in the pool and swam as fast as it could, carrying Freddie with it.

Freddie was such a small chap, and the turtle was so large, that it did not mind the weight on its back. But there was no telling when it would sink down.

"Take me off! Take me off!" cried Freddie again.

"That's all right," said the Aquarium man. "Don't be afraid, little boy.

The turtle won't hurt you, and we'll soon have you off his back. He won't bite you, and you're having a fine ride!"

Freddie, it seemed, had not thought of that before.

"That's so!" he exclaimed, and his face did not show much fright now. "I am having a ride, ain't I?"

Flossie heard this, and then, instead of being afraid her brother would be hurt, she cried out:

"Oh, I want a turtle ride, too!"

"No!" exclaimed Mr. Bobbsey, who was not so worried, now that he saw the Aquarium man on his way to get Freddie. "One turtle ride is enough for the family. Hold fast, Freddie!" he called, as the turtle came around on the side of the pool near to where the Bobbseys stood.

By this time the man was out on the middle of the wooden piece that held the heavy wire netting, and as the turtle swam near that the man leaned over and quickly lifted Freddie from the swimming creature's back.

"There you are, my boy!" cried the man, as he held Freddie out to another attendant who had come to help. "Now you're all right except for wet feet, and we can dry them for you in the engine room."

"We have to keep the boilers going in Winter to warm the water for the tropical fish," said the man to Mr. Bobbsey. "Take your little boy there and we'll dry his shoes and stockings."

"Thank you," said Mr. Bobbsey. By this time Freddie was safely out of the turtle pool, and the big creature, relieved of that strange thing on his back, had sunk down to the bottom of the pool, as though to hide away. It was lucky he had kept himself afloat as long as he had, or Freddie might have been wet all over.

"Well, you do seem to have the queerest things happen to you, Freddie,"

said his father with a smile. "What will you do next?"

"I--I couldn't help this, Daddy," said the little fellow. "I--I just slipped!"

"Well, don't do it again," said the Aquarium man, with a smile. "If you had fallen in the other pool, where there are half a dozen turtles, though none as large as the one you rode on, you might have been bitten. But you're all right. Now come along and we'll dry you out."

It was an easy matter to dry Freddie's feet and legs in front of the warm furnaces in the boiler room, but his shoes and stockings did not get rid of their wetness so soon. And, as Mr. Bobbsey did not want to wait, he sent one of the attendants out to buy new shoes and stockings for his son.

With these on, and carrying the damp ones in a bundle, Freddie was soon ready to go home.

"I guess I've had enough of the 'quarium," he said. "Anyhow I had a funny ride."

"I should say you did!" agreed Bert. "I wish we had a picture of you riding around on the back of that turtle."

Mrs. Bobbsey was at first alarmed, and then she laughed, when told of what had happened. She made Freddie drink some hot milk, so he would not get cold, but he told her the water of the turtle pool was warm, as it always is in Winter, and he said: "I don't think I'll even have the snuffles,"