WILL lost no time in getting off his clothes. He felt hot and fishy, and the cool, tawny ripples allured him. Reube tested the anchor to see that the Dido held fast, and then began more slowly to undress. The anchor had been dropped not more than thirty or forty feet from the sand spit, but the boat had swung off before the light breeze till the distance was increased to a score of yards.

“That’s quite a swim for me, Will,” said Reube, doubtfully, eyeing the tide.

“Nonsense! You can swim twice as far as that if you only think so,” asserted Will with confidence. “By the way, I wonder what makes you such a duffer in the water. That’s your weak point. I must take you in hand and make a water dog of you.”

“I just wish you would,” said Reube. “I don’t seem to really get hold of myself in the water. I have to work frightfully hard to keep up at all, and then I’m all out of breath in less than no time. Why is it, I wonder?”

“Well,” answered Will, “we’ll see right now. You swim over to the bar yonder, and I’ll stand here and watch your action. I fancy you don’t use your legs just right.”

“It’s too far. Pull her in a little way,” urged Reube.

Laughingly Will complied. He pulled on the rope till the Dido was almost straight above the anchor. Then Reube slipped overboard with an awkward splash and struck out for the sand spit.

His progress was slow and labored. His strokes made a great turmoil, but produced little solid result. Will’s face wore a look of amused comprehension, but he refrained from criticism till the swimmer had reached his goal and drawn himself out panting on the sand.

“How’s that?” asked Reube.

“O, it’s all wrong! If it was anyone less obstinate than you he wouldn’t keep afloat half a minute struggling that way,” answered Will. “But wait a moment and I’ll show you what I mean.”

With a graceful curve Will plunged into the water as smoothly as if he had been oiled. A few long, powerful strokes brought him to the spot where his comrade was standing.

“Now,” said he, “get in there in front of me when the water comes up to the lower part of your chest. You use your legs wrong, and your arms too. Your arms don’t make a quarter the stroke they ought to, and your fingers are wide open, and your hands press out instead of down on the water too much. Keep your fingers together, and turn your palms so that they tend to lift you, instead of just pushing the water away on each side. And, moreover, finish your stroke!”

“And what about my legs?” asked Reube, humbly.

“Never mind them till we get the hands right,” insisted Will. “Now lean forward slowly, with your back hollowed well and chin up, your arms out straight ahead, and straighten your legs. Right! Now round with your arms in a big, fine sweep, drawing up your legs at the same time. That’s more like it. But your legs—you draw them up right under you with the knees close together. That’s all wrong. Didn’t you ever watch a frog, old man? As you draw up your legs spread your knees wide apart like one of those tin monkeys shinning up a stick. Try again. M-m-m! Yes, that’s something like what I want. You see, with the knees doubled up wide apart they have their separate motions as you kick them out again. The legs press the water down, and so do some lifting. The feet push you ahead, and at the same time you thrust a wedge of water backward from between your legs as they come strongly together.”

“That’s reasonable,” assented Reube, practicing diligently. In a few minutes he had made a marvelous advance in his method. Will sometimes swam beside him, sometimes stood on the bar and criticised.

All at once, in the midst of an encouraging speech he clapped his hands to his heart with a cry of pain, sank upon the sand, and called out sharply:

“Come here quick, quick, Reube!”

Reube remembered his lessons even in his anxiety, and with long, powerful strokes made his way swiftly to Will’s side. As he landed Will straightened himself up with a grave smile, and held one his hand to draw Reube back from the water’s edge.

“I’m all right now,” said he.

“But what was the matter?” queried Reube, in impatient astonishment.

“Why, just that,” replied Will, suddenly pointing to the water.

Reube turned and glanced behind him.

“Sharks!” he almost shouted. And there, sure enough, were two black triangular fins cleaving the water where he had just been swimming.

After staring for a moment or two in silence he turned again and met the inscrutable smile on his companion’s face. He held out his hand.

“I understand,” said he. “If I’d got flurried in the water I would have forgotten the lessons you have just given me, and couldn’t have got to shore fast enough.” And in the love and admiration which glowed in his eyes Will read sufficient thanks.

“Now the question is,” mused the latter, “how we’re going to get to the boat.”

“Seems to me we’d better stay right here for the present,” said Reube, drily.

“Yes,” suggested Will; “and when the tide gets a little higher what then?”

“Um!” said Reube, “I was forgetting this is not an honest island. This does certainly look awkward. But what do you suppose those chaps are doing, cruising to and fro right there? Are they just catching herring? Or are they after us?”

“You would know what they were after if you had seen the way they streaked in here when they got a glimpse of you,” responded Will.

“I don’t see what we’re going to do about it,” said Reube presently, after they had gazed at their dreadful besiegers in gloomy silence. “But there’s something in the way of a weapon which we might as well secure anyway.” And running to the other side of the sand spit he snatched up a broken picket which had been left there by the previous ebb. “It’s better than nothing,” he insisted.

“Reube,” said Will, “if we stay here it’s all up with us pretty soon. We’ll just make a dinner for those chaps. It seems to me I’d better take that stick you’ve got there and make a dash for the Dido. You know I swim wonderfully fast, and dive like a fish; and I can perhaps manage to jab the sharks with that picket, or scare them off by making a great splash in the water. If I succeed in getting to the Dido I’ll bring her over for you, and we’ll fix the enemy with a couple of bullets.”

“No,” said Reube, doggedly, grasping the other firmly by the shoulder. “You just wait here. We’ll fight this thing out side by side, as we have fought things out before. Remember the cave, Will! And we won’t fight till we have to. We’re safe for a half hour yet anyway.”

“And then the distance between us and the boat will be all the greater,” urged Will.

“No, the wind’s falling and it may turn and blow the Dido over this way,” insisted Reube. “See, the fitful little gusts now. Or one of the other boats may come in sight near enough for us to hail her. You never can tell what may happen, you know.”

Indeed, as a matter of fact, Reube was right. He could not tell what would happen. What actually did happen was neither of the things which he had suggested, and yet it was the most natural thing in the world.