"Seems to me," said Cap'n Bill, as he sat beside Trotunder the big acacia tree, looking out over the blueocean, "seems to me, Trot, as how the more we know, themore we find we don't know."

"I can't quite make that out, Cap'n Bill," answeredthe little girl in a serious voice, after a moment'sthought, during which her eyes followed those of theold sailor-man across the glassy surface of the sea."Seems to me that all we learn is jus' so much gained."

"I know; it looks that way at first sight," said thesailor, nodding his head; "but those as knows the leasthave a habit of thinkin' they know all there is toknow, while them as knows the most admits what aturr'ble big world this is. It's the knowing ones thatrealize one lifetime ain't long enough to git more'n afew dips o' the oars of knowledge."

Trot didn't answer. She was a very little girl, withbig, solemn eyes and an earnest, simple manner.Cap'n Bill had been her faithful companion for yearsand had taught her almost everything she knew.

He was a wonderful man, this Cap'n Bill. Not sovery old, although his hair was grizzled -- what therewas of it. Most of his head was bald as an egg andas shiny as oilcloth, and this made his big ears stickout in a funny way. His eyes had a gentle look andwere pale blue in color, and his round face was ruggedand bronzed. Cap'n Bill's left leg was missing, fromthe knee down, and that was why the sailor no longersailed the seas. The wooden leg he wore was goodenough to stump around with on land, or even to takeTrot out for a row or a sail on the ocean, but when itcame to "runnin' up aloft" or performing activeduties on shipboard, the old sailor was not equal tothe task. The loss of his leg had ruined his careerand the old sailor found comfort in devoting himselfto the education and companionship of the little girl.

The accident to Cap'n Bill's leg bad happened atabout the time Trot was born, and ever since that hehad lived with Trot's mother as "a star boarder,"having enough money saved up to pay for his weekly"keep." He loved the baby and often held her onhis lap; her first ride was on Cap'n Bill's shoulders,for she had no baby-carriage; and when she beganto toddle around, the child and the sailor becameclose comrades and enjoyed many strange adventurestogether. It is said the fairies had been present atTrot's birth and had marked her forehead with theirinvisible mystic signs, so that she was able to see anddo many wonderful things.

The acacia tree was on top of a high bluff, but apath ran down the bank in a zigzag way to the water'sedge, where Cap'n Bill's boat was moored to a rockby means of a stout cable. It had been a hot, sultryafternoon, with scarcely a breath of air stirring, soCap'n Bill and Trot had been quietly sitting beneaththe shade of the tree, waiting for the sun to get lowenough for them to take a row.

They had decided to visit one of the great caveswhich the waves had washed out of the rocky coastduring many years of steady effort. The caves werea source of continual delight to both the girl and thesailor, who loved to explore their awesome depths.

"I b'lieve, Cap'n," remarked Trot, at last, "thatit's time for us to start."

The old man cast a shrewd glance at the sky, thesea and the motionless boat. Then he shook his head.

"Mebbe it's time, Trot," he answered, "but I don'tjes' like the looks o' things this afternoon."

"What's wrong?" she asked wonderingly.

"Can't say as to that. Things is too quiet to suitme, that's all. No breeze, not a ripple a-top the water,nary a gull a-flyin' anywhere, an' the end o' the hottestday o' the year. I ain't no weather-prophet, Trot, butany sailor would know the signs is ominous."

"There's nothing wrong that I can see," said Trot.

"If there was a cloud in the sky even as big as mythumb, we might worry about it; but -- look, Cap'n! --the sky is as clear as can be."

He looked again and nodded.

"P'r'aps we can make the cave, all right," he agreed,not wishing to disappoint her. "It's only a little wayout, an' we'll be on the watch; so come along, Trot."

Together they descended the winding path to thebeach. It was no trouble for the girl to keep herfooting on the steep way, but Cap'n Bill, because ofhis wooden leg, had to hold on to rocks and roots nowand then to save himself from tumbling. On a level pathhe was as spry as anyone, but to climb up hill or downrequired some care.

They reached the boat safely and while Trot wasuntying the rope Cap'n Bill reached into a crevice ofthe rock and drew out several tallow candles and a boxof wax matches, which he thrust into the capaciouspockets of his "sou'wester." This sou'wester was ashort coat of oilskin which the old sailor wore on alloccasions -- when he wore a coat at all -- and thepockets always contained a variety of objects, usefuland ornamental, which made even Trot wonder where theyall came from and why Cap'n Bill should treasure them.The jackknives -- a big one and a little one -- the bitsof cord, the fishhooks, the nails: these were handy tohave on certain occasions. But bits of shell, and tinboxes with unknown contents, buttons, pincers, bottlesof curious stones and the like, seemed quiteunnecessary to carry around. That was Cap'n Bill'sbusiness, however, and now that he added the candlesand the matches to his collection Trot made no comment,for she knew these last were to light their way throughthe caves. The sailor always rowed the boat, for hehandled the oars with strength and skill. Trot sat inthe stern and steered. The place where they embarkedwas a little bight or circular bay, and the boat cutacross a much larger bay toward a distant headlandwhere the caves were located, right at the water'sedge. They were nearly a mile from shore and abouthalfway across the bay when Trot suddenly sat upstraight and exclaimed: "What's that, Cap'n?"

He stopped rowing and turned half around to look.

"That, Trot," he slowly replied, "looks to me mightylike a whirlpool."

"What makes it, Cap'n?"

"A whirl in the air makes the whirl in the water. Iwas afraid as we'd meet with trouble, Trot. Thingsdidn't look right. The air was too still."

"It's coming closer," said the girl.

The old man grabbed the oars and began rowing withall his strength.

"'Tain't comin' closer to us, Trot," he gasped; "it'swe that are comin' closer to the whirlpool. The thingis drawin' us to it like a magnet!"

Trot's sun-bronzed face was a little paler as shegrasped the tiller firmly and tried to steer the boataway; but she said not a word to indicate fear.

The swirl of the water as they came nearer made aroaring sound that was fearful to listen to. So fierceand powerful was the whirlpool that it drew the surfaceof the sea into the form of a great basin, slantingdownward toward the center, where a big hole had beenmade in the ocean -- a hole with walls of water thatwere kept in place by the rapid whirling of the air.

The boat in which Trot and Cap'n Bill were riding wasjust on the outer edge of this saucer-like slant, andthe old sailor knew very well that unless he couldquickly force the little craft away from the rushingcurrent they would soon be drawn into the great blackhole that yawned in the middle. So he exerted all hismight and pulled as he had never pulled before. Hepulled so hard that the left oar snapped in two andsent Cap'n Bill sprawling upon the bottom of the boat.

He scrambled up quickly enough and glanced over theside. Then he looked at Trot, who sat quite still, witha serious, far-away look in her sweet eyes. The boatwas now speeding swiftly of its own accord, followingthe line of the circular basin round and round andgradually drawing nearer to the great hole in thecenter. Any further effort to escape the whirlpool wasuseless, and realizing this fact Cap'n Bill turnedtoward Trot and put an arm around her, as if to shieldher from the awful fate before them. He did not try tospeak, because the roar of the waters would havedrowned the sound of his voice.

These two faithful comrades had faced dangers before,but nothing to equal that which now faced them. YetCap'n Bill, noting the look in Trot's eyes andremembering how often she had been protected by unseenpowers, did not quite give way to despair.

The great hole in the dark water -- now growingnearer and nearer -- looked very terrifying; but theywere both brave enough to face it and await the resultof the adventure.