The island was shaped like a little hill, high in the middle, and Margy and Mun Bun had kept stepping back until they now stood on the highest part in the middle.

All about them was the water, deeper in some places than in others.  And you may be sure that the little boy and his sister did not try to get off the high spot.  There the water was only over their feet, but if they stayed there much longer it might cover their heads.

However no such dreadful thing happened, for Mr. Burnett steered his boat up to them until it grounded in the sand of the island that was now under water.

“Now you’re all right!” said the kind man.  He shut off his motor and jumped over the side of the boat.  Right into the water he stepped, but as he had on high rubber boots he did not get his feet wet.

Mr. Burnett picked up Margy and set her down in his boat.

“Oh, look at the big lobsters!” cried the little girl.  “Will they pinch me?”

Well might she ask that question, for the bottom of the boat was filled with lobsters with big claws, some of which were moving about, the pinching parts opening and shutting.

“They won’t hurt you,” said Mr. Burnett with a laugh.  “Just keep up on the seat, Margy, and you won’t get pinched.”

The seats in the lobster boat were broad and high, and on one of them Margy and Mun Bun, who was soon lifted off the island to her side, were safe from the lobsters, which Mr. Burnett had taken from his pots, some miles out at sea.

“How did you come to go on the island when the tide was rising?” asked the fisherman, as he started his boat once more.

“The water was low, and we waded out barefoot,” explained Margy.

“We were goin’ to dig clams,” added Mun Bun.

“But we couldn’t find any,” continued Margy.  “And then when we went to wade back home the water got deep and we were afraid.”

“I should think you would be!” replied the lobster fisherman.  “Well, I’m glad I heard you call.  It wouldn’t be very nice on your island now.”

The children looked back.  Their island was out of sight.  It was “submerged,” as a sailor would say, meaning that it was under the water.  For the tide had risen and covered it.

“Will you take us home?” asked Margy.

“That’s what I will,” said the lobster fisherman.  “I’ll take you right up to Mr. Bunker’s pier.  I guess your folks don’t know where you are, nor what trouble you might have been in if I hadn’t come along just when I did.”

And this was true, for neither Daddy nor Mother Bunker, nor Cousin Tom nor his wife, nor any of the other little Bunkers had heard the cries of Mun Bun and Margy.

But as the motor-boat went puffing up to the little wharf the noise it made was heard by Mr. and Mrs. Bunker, who ran down from the cottage to see it, as they wanted to buy a fresh lobster and they had been told that Mr. Burnett might soon come back from having gone to lift his pots.