Breakfast was cleaned away and Betty, with Mollie at her heels, made a rush for the bedroom.

"I'm willing to wager anything," called the former, gaily, "that I'll be in my bathing suit before any of the rest of you have started."

"I hope the water isn't too cold," Grace shivered, as she took out her bathing suit. "If there is anything I hate, it's trying to swim in icy water. It almost makes my heart stop beating."

"All right, we'll have the weather man heat it for you," said Betty, slipping into her neat little suit. "I don't know how the water can be cold, though," she added, "the air is suffocating to-day."

"Now--one, two, three--go!" and they were off like four little black sprites, down the broad stairway and into the living room where the boys were already assembled, talking to the chaperon.

The boys wore raincoats over their bathing suits; and, as the girls entered the room, they shouted a merry greeting.

"So soon?" called Frank in surprise. "Why, we didn't expect to see you for an hour at least."

"An hour?" said Betty, with feigned indignation--for she was a good little actress, was Betty. "Why, we thought you were never coming!"

"You mean to say you were waiting for us?" said Allen, incredulously.

"Betty, are you telling the truth? Mrs. Irving, is she?"

"I assure you I was too busy finding my bathing suit and getting into it to know just when the girls were ready," responded the chaperon.

At one part of the island the ground dipped gradually so that one might have any depth of water desired, and it was to this part that the young folks made their way.

"Remember----" said Frank, referring to the conversation of the night before, "remember, you girls will have to prove your claims to championship swimming this morning. If you were just faking, now is the time we'll find you out."

"We're not faking," Mollie denied stoutly. "I learned to swim when I was nine years old, and I've been swimming ever since."

"Really?" Roy inquired with interest. "Then you must be Mollie's ghost, while the real Mollie is swimming around out there somewhere," waving his hand in the direction of the water, "chumming with some of the beautiful water nymphs. Just think, nothing to do but swim for--how many years is it, Mollie?" he asked.

"Goose!" was all she answered, but that one little word managed somehow to contain a world of scorn.

"You try it first, Will," begged his sister. "Then you can tell us whether it is cold or not."

"Say, what kind of sport are you, anyway?" Will demanded. "That's the way with girls--they all make a big bluff about being able to do what we can, and then when it actually comes down to business they want to try it on us first. I'd like to see one of you go in first!"

Betty made a dash for the water. "Wouldn't it be nice," she flung back at him over her shoulder, "if all wishes could be granted so easily.

Come on, girls--we'll show them a thing or two," and she waded in till the water was above her waist, then plunged in over her head.

Mollie followed close upon her heels and it was a moment before the boys realized what had happened, and could rouse themselves to action.

"Come on, fellows!" Allen shouted. "We can't let two girls get the best of us like that."

Mrs. Irving, who was at home in the water, entered and swam out boldly.

"Are you going to stay there?" Frank shouted to Amy and Grace, who stood uncertainly on the bank, undecided whether to advance or retreat. "Come on in--the water's fine."

Thus encouraged, the two girls threw caution to the winds, and waded in till the warm water was up to their shoulders.

"Oh, it is wonderful!" cried Amy. "Look how far we are behind. Let's see if we can't catch up with them." And they started off with a will after their deserting comrades.

It was not long before the powerful strokes of the boys brought them up beside Mollie and Betty who were swimming easily.

"Hello, runaways," was Frank's greeting, turning over on his back and propelling himself by a whirlpool motion of his arms. "Thought you'd give us the slip, did you? Well, we shall see."

Betty followed Frank's example, floating lazily on the still surface of the water.

"We weren't running away," she said; "we just wanted to show you we weren't afraid, that's all."

"I'll give you a race to that floating log out there, Betty."

Betty turned over and regarded the log in question with thoughtful eyes.

"All right," she agreed, after a moment's hesitation. "I guess I can make that easily enough. Will you call the start?"

"Just as you say," he answered. "We are almost even now, and when I say go, we're off. Agreed?"

"Uh'huh," answered Betty.

"All right. One--two--three--go!"

They shot forward together, side by side and shoulder to shoulder, each determined to save his strength for the final spurt.

By this time the others had come up and were watching the race with interest.

On, on the two racers went, with no apparent effort, until half the distance to the log had been covered. It was then that the watchers noticed the change. Betty lengthened her stroke a trifle and forged ahead, while Frank still kept the same steady stroke.

Then, when more than half of the remaining distance had been covered, Frank evidently made up his mind that it was time to show those people some real speed. Suddenly he dropped the lazy stroke, and it seemed as though he were imbued with new life. His arms and legs worked together with the precision of a machine and he shot through the water like a catapult.

Betty was not prepared for so sudden a transformation, but her surprise lasted only a minute. Gallantly she gathered all her strength and made a dash for the goal.

"I see Betty's finish," Will was saying, when Mollie cried excitedly:

"You just watch Betty. Did you ever see a girl like her?"

As Allen came up beside the pair he thought that at last he and Mollie had found something to agree upon.

They watched Betty with straining eyes.

"She'll do it!" cried Allen. "I never thought it was possible for a girl to swim like that. Look, she has caught up to him."

It was so. Betty had used the last ounce of strength in her strong, young arms and the result was a tie.

She and Frank laid hands upon the log at one and the same instant.

Frank shook the water from his eyes, and regarded his rival in amazement. "How did you ever do it?" he questioned. "I thought I had you beat a mile."

"Well, that's where you had another think coming." Betty would not have been human had she not gloried in this victory--for even a tie with one of Frank's strength and muscle was a triumph. "I told you I could swim."

"Hoorah for the cham_peens_!" shouted Will as the others reached the goal a few moments later. "That's pretty good work, Betty. I have to hand it to you."

"Don't you think we had better get to the shore and rest a while?" Roy suggested. "Amy and Grace seem to have gotten there before us, and Mrs.