Captain Crane was worried. So were Mr. and Mrs. Bobbsey and Cousin Jasper. Even Flossie and Freddie, young as they were, could tell that.

"Maybe a big mud turkle came and pulled the ship away," said Flossie.

"Or a whale," added Freddie. Any big fish or swimming animal, the little twins thought, might do such a thing as that.

"No, nothing like that happened," said Captain Crane. "And yet the _Swallow_ is gone. The men could not have thought a storm was coming up, and gone out to sea to be safe. There is no sign of a storm, and they never would have gone away, unless something happened, without blowing a whistle to tell us."

"Maybe," said Bert, "they got word from Jack, on the other island, to come and get him right away, and they couldn't wait for us."

Captain Crane shook his head.

"That couldn't happen," he said, "unless another boat brought word from poor Jack. And if there had been another boat we'd have seen her."

"Unless both boats went away together," suggested Mr. Bobbsey.

"No, I think nothing like that happened," said the captain.

"But what can we do?" asked Mrs. Bobbsey. "Shall we have to stay on this island until the _Swallow_ comes back?"

"She may not be gone very long," Mr. Bobbsey said.

"We can camp out here until she does come back," observed Nan. "We have lots left to eat."

"There won't be much after supper," Bert said. "But we can catch some turtles, or find some more eggs, and get fish, and live that way."

"I'll catch a fish," promised Freddie.

"I don't understand this," said Captain Crane, with another shake of his head. "I must go out and have a look around."

"How are you going?" asked Mrs. Bobbsey.

"In the small boat. I'll row out into the bay for a little way," said the seaman. "It may be that the _Swallow_ is around some point of the island, just out of sight. I'll have a look before we get ready to camp here all night."

"I'll come with you," offered Cousin Jasper.

"All right, and we'll leave Mr. Bobbsey here with his family," the captain said. "Don't be afraid," he added to the children and Mrs.

Bobbsey. "Even if the worst has happened, and the _Swallow_, by some mistake, has gone away without us, we can stay here for a while. And many ships pa.s.s this island, so we shall be taken off pretty soon."

"We can be like Robinson Crusoe, really," Bert said.

"That isn't as much fun as it seems when you're reading the book," put in his mother. "But we will make the best of it."

"I think it'd be fun," murmured Freddie.

Captain Crane and Cousin Jasper got in the small boat and rowed out into the bay. Anxiously the others watched them, hoping they would soon come back with word that the _Swallow_ had been blown just around "the corner," as Nan said, meaning around a sort of rocky point of the island, beyond which they could not look.

"I do hope we shall not have to camp out here all night," said Mrs.

Bobbsey, with a little shiver, as she looked around.

"Are you afraid of the mud turkles?" asked Flossie.

"No, dear. But I don't want to sleep on the beach without a bed or any covers for you children."

"Perhaps we shall not have to," said Mr. Bobbsey.

They waited a while longer, watching the small boat in which were Captain Crane and Cousin Jasper, until it was rowed out of sight. Bert did not seem to mind much the prospect of having to stay all night on Palm Island.

Nan, however, like her mother and her father, was a bit worried. But Flossie and Freddie were having a good time digging in the sand with clam sh.e.l.ls for shovels. The little twins did not worry about much of anything at any time, unless it was getting something to eat or having a good time.

"I know what I'm going to build!" cried Freddie.

"What?" demanded his twin quickly.

"I'm going to build a great big sand castle."

"You can't do it, Freddie Bobbsey. The sand won't stick together into a castle."

"I'm going to use wet sand," a.s.serted Freddie. "That will stick together."

"You look out, Freddie Bobbsey, or you'll fall in!" cried his sister, when Freddie had gone further down near the water where the sand was wet.

"Freddie! Freddie! keep away from that water!" cried Mrs. Bobbsey. "I don't want you to get all wet and dirty."

"But I want to build a sand castle."

"Well, you come up here where the sand is dry and build it," continued Mrs. Bobbsey.

"All right. In a minute," answered Freddie.

Mr. Bobbsey was straining his eyes, looking out toward the point of rock, around which the rowboat had gone, and his wife was standing beside him, gazing in the same direction, when Bert, who looked the other way, cried:

"There she comes now! There's the _Swallow_!"

And, surely enough, there she came back, as if nothing had happened.

Mr. Bobbsey waved his hat and some one on the motor boat blew a whistle.

And then, as if knowing that something was wrong, the boat was steered closer to sh.o.r.e than it had come before, and Mr. Chase cried:

"What's the matter? Did anything happen?"

"We thought something had happened to you!" shouted Mr. Bobbsey.

"Captain Crane and Mr. Dent have gone off in the small boat to look for you."

"That's too bad," said Mr. Chase. "While you were away, on the other side of the island, we finished work on the engine. We wanted to try it, so we pulled up anchor and started off. We thought we would go around to the side of the island where you were, but something went wrong, after we were out a little while, and we had to anchor in another bay, out of sight. But as soon as we could we came back, and when I saw you waving your hat I feared something might have happened."

"No, nothing happened. And we are all right," said Mr. Bobbsey, "except that we were afraid we'd have to stay on the island all night. And Captain Crane has gone to look for you."

"I'm sorry about that," returned the engineer. "It would have been all right, except that the motor didn't work as I wanted it to. But everything is fine now, and we can start for the other island as soon as we like. I'll blow the whistle and Captain Crane will know that we are back at our old place."