CHAPTER XI.

THEY FIND THE CAVE.

They were walking slowly along listening with all their ears and keeping their eyes turned, for the most of the time, toward the grove. The captain was in the lead with Mr. Lakewood close behind him; then came Jack followed by Pat, while Bob brought up the rear. They had just passed the last of the trees when Bob felt the swish of some object as it flew past his head and landed on the back of the first mate's head with a resounding crack. That worthy at once pitched forward and fell face down. Bob sprang and turned him over at the same time calling to the others.

"Something hit him on the back of the head," he explained as they turned and rushed back. "It was that nut there."

Pat was unconscious but only for a minute. "Was it lightning?" he gasped as he struggled to his feet.

"No, it was nut," Jack grinned, but the hot-headed Irishman was in no mood to catch the pun.

"Whot was it thin," he demanded rubbing the back of his head.

"Someone or something threw this nut at us and hit you," Bob told him as he picked up the nut.

"An' it's meself as he can't do thot wid and git away wid it," he sputtered starting back toward the grove.

But the captain caught him by the arm and held him back. "Easy there now," he cautioned.

"Aisy me eye. I'm going ter git the spaleen whot threw thot nut, I'm tellin' yer."

"Not that way you aren't," the captain insisted easily holding the struggling mate. "Maybe it was a gorilla or an orang-outang and if it was he'd make mince meat of you if you go rushing in there."

"But--"

"No buts about it. You do as I say or I'll put you in irons when we get back to the ship," the captain told him, but the boys caught the twinkle in his eye and knew that he was only bluffing. Evidently the Irishman caught it also for his look of fierce determination vanished and a good natured grin spread over his face.

"All right," he said. "Yer're the boss," and the captain let go his hold.

"We'll investigate this grove when we're better armed," the captain promised them as he started off again.

Once more it seemed to Jack that he caught the sound of laughter from back in the depths of the woods, but as none of the others seemed to hear it, he said nothing.

It was just eleven when, finally, they reached the other end of the island and stood on the edge of the cliff. Three or four times they had asked Mr. Lakewood what he thought about it being the right place during the walk from the grove. But he had refused to commit himself until they had reached the very end of the island.

"I think it's it," he said slowly, "but I'll knew for sure in a short time now. If I'm right there's a passage a short distance off there which leads down to the water and in that passage is the entrance to the cave of pearls."

"Let's go then," Jack said impatiently.

"At once," his uncle told him as he turned to lead the way. "Here it is for a fact," he declared a few minutes later as he stopped and pointed to a narrow defile which separated the cliff into two parts.

"Hurrah!" shouted both of the boys.

"Follow me, now, and be careful where you step; it's a bit rough if I remember rightly," their uncle said as he started down the narrow defile.

He was right when he called the path rough and they had to go very slowly picking their way over rocks some of them as large as a barrel. But they had only a short distance to go and soon the leader stopped and pointed to an opening which appeared as though cut in the wall of stone.

"Now for it," he said, pulling a flashlight from his pocket.

The opening was tall enough for them to walk upright but so narrow that they had to go single file and even then their arms sometimes touched both sides of at the same time.

"Good thing none of us is very fat," Jack chuckled as he followed close at his uncle's heels.

"It's only a step or two farther," Mr. Lakewood said and, a moment later he stopped and threw the light from his flash about a small chamber just in front of where they stood.

Then a great wave of disappointment swept over the boys for the floor of the cave was bare. Not a single oyster shell was to be seen.

"Stung," Jack gasped.

"Looks that way, doesn't it," his uncle said with no trace of disappointment in his voice.

"But where did they go?" Jack asked.

For a moment no one replied and then Bob said: "Well, I've never heard of oysters walking so I reckon we've got to conclude that some one has beaten us to them."

"Faith an' it's a great brain you got," Pat laughed.

"Well, boys, it's getting along toward dinner time, so I reckon we'd better be getting back to the boat," Mr. Lakewood said as he turned and started out through the opening.

"He's got something up his sleeve," Bob whispered to Jack as they fell in behind the others.

"What makes you think so?"

"Because he didn't seem to mind it."

"He didn't for a fact. But what can he have up his sleeve as you put it?"

"We'll have to wait and see. He knows."

It was well past twelve o'clock when they were back on board and Wong, having kept dinner waiting all of ten minutes, was in a bad mood.

"You velly mooch late," he snapped as they entered the mess cabin.

"But we're hungry enough to make up for it," Jack told him.

"You velly lucky to gleet anything," was the answer he got.

"It's a good thing for us that Wong's bite isn't as bad as his bark," Bob laughed as they sat down at the table.

"You didn't seem to be much disappointed, Uncle Si," Jack ventured when they were nearly through the meal and he had not mentioned the subject.

"No? Well, you see, I didn't expect to find them there."

"You didn't?" both boys gasped. "Then what did you come for?" Bob asked, a look of amazement on his face.

"Pearls," laconically.

"But--"

"Give me time and I'll tell you all about it," his uncle interrupted. "You see, the chances are that those oysters would have rotted long before this if no one had found them."

"Would that have spoiled the pearls?" Jack asked.

"I hardly know about that but the chances are that the shells would have split open and the tide would have washed them out to sea. I think I told you that the tide makes up in the cave through some opening that we didn't see. So, that's why I didn't really expect to find any pearls in the cave."

"Then you just took a long chance?" Jack asked.

"Not quite so long as you think, perhaps, although I might as well confess that it's a chance all right."

"You mean----"

"I mean that, although those particular pearls are undoubtedly gone, I hope to find others."

"Where?" Bob asked.

"In the water just off the head of the island."

"But what makes you think there are any oysters there?"

"I saw some there when I was here before, and for another thing, I believe that whoever hid those oysters in there gathered them close by. These natives around here are a mighty lazy lot as a rule and, for that reason, I figure that they didn't find them a great ways off."

"But where--"

"So when I outfitted the boat," Mr. Lakewood went on ignoring the interruption, "I included some oyster rakes and to-morrow we're going oyster hunting."

"How about a diving suit?" Jack asked.

"Well, to tell the truth, we've got a first class outfit on board but, unless the water's deeper off the end there than I think, we won't need it."

"Looks as though you had thought of about everything," Bob grinned.

"Had to. You see, it's too far to go back for something you forgot to bring," his uncle smiled.

"How about this afternoon?" Bob asked.

"No, we're not going to start till to-morrow; the old man needs this afternoon to get rested up in after that tramp."

"Didn't I tell you he had something up his sleeve?" Bob asked a little later after they had finished dinner and their uncle had announced that he was going to his cabin for a nap. The two boys were sitting beneath the awning on the forward deck and chafing under the enforced delay.

"Well, I didn't bet against it, did I?" Jack returned. "Reckon I suspected it as much as you did."

For half an hour they sat and talked about the coming oyster hunt and again thrashed over the adventure of the morning. Several times Bob had yawned and finally Jack advised him to go and take a nap.

"Believe I will," he said, getting up from his chair. "Coming along?"

"I'm not sleepy," Jack returned in a disgusted tone. "I use my nights for that purpose," he added turning his eyes toward the southern end of the island.

As Bob started for the cabin Jack arose and leaned on the rail. "Just a minute, Bob," he said, and Bob quickly returned to his side.

"What is it?"

"Look over there just at the top of that knoll."

"I don't see anything."

"Keep your eyes glued on it while I get the glasses," Jack ordered. "I saw something move there."

He was back in less than a minute. "Seen anything?" he asked.

"Lots of sand," Bob replied.

For a minute Jack gazed through the glasses and then handed them to Bob.

"Look just to the right," he ordered.

"It's nothing but a stump," Bob said after taking a long look.

"Stump, your eye."

Jack snatched the glass from his hand and looked again.

"It was moving when I looked before," he said as he handed them back to his brother.

"And it is now," Bob declared excitedly a moment later. "It's either a man or--or--"

"Or something else," Jack finished the sentence.

"It must be a man. No other animal would crawl along like that."

"But what's he trying to do?"

"Trying not to let us see him, I'd say."

"Of course, smarty, but what's he after?"

"Probably wants to find out something about us."

"Well, he's coming in the right direction if he does."

"He's stopped now," Bob announced a moment later. "Now he's crawling back."

"Reckon he didn't find out much."

"He's gone over the knoll, now."

For nearly an hour they watched the distant knoll but the object did not again appear.

"How about that nap?" Jack asked.

"Nothing doing."

"Then I'll beat you a game of checkers."

"You mean you'll try."

They played checkers until supper time and, to Jack's great joy, he was two games ahead when the bell rang. During the meal they told their uncle and the captain what they had seen.

"And you think it was a man?" Captain Ole asked, when they had finished.

"I'm not sure," Bob replied, "but it looked more like a man to me than anything else. It was too far to be sure."

"Well, whatever it is we'll have to look out for it," Mr. Lakewood declared, "It evidently doesn't like our company."

It was sometime during the night when the boys were awakened by the noise of what sounded like a fight just outside their cabin.

"What the dickens!" Bob cried as he jumped from his bunk wide awake.

He pulled open the door and rushed out on deck closely followed by Jack. There, close to the rail, two figures were locked in each others' arms and swaying this way and that, while loud hoarse grunts came from one or both of them. For an instant the boys hesitated as though uncertain what to do. Then, with a loud shout to Jack to "come on" Bob sprang forward. Only a few feet separated him from the fighters but, before he could reach them, one was hurled violently to the deck while the other, with a wild bellow of rage, leaped for the rail and disappeared over the side. A loud splash followed as he struck the water.

Knowing that it would be too dark to see a swimming object in the water, Bob quickly turned to the man who was lying motionless on the deck.

"It's Pat," he cried, as he turned him over.

"What's all the rumpus?" Mr. Lakewood asked the question as he came running toward them.

"It's Pat," Jack told him. "Something threw him down and then jumped overboard."

"Is he dead?" Mr. Lakewood asked anxiously.

"Only got the wind knocked out of him, I think," Bob, who was working Pat's arms up and down, replied.

After what seemed a long time the breath slowly came back to the mate's lungs and, finally, he was able to speak.

"Thot makes twice," were the first words he gasped.

"Take it easy a bit," Bob cautioned helping him to his feet.

By this time Captain Ole and two of the sailors had joined the party and, after waiting a few minutes until he had fully recovered his wind, Pat told them what had happened.

"Faith an' it's meself as was standin' by the railin' thar lookin' out over the water, whin somethin' grabbed me from fornist before I had time ter turn. He got his arm around me neck an' all but had me wind shut off fer a minute. But I got me neck free an' we wint at it. But it's meself as'll tell the world he's strong. Sure an' I'm some scrapper meself but that guy'd had me if the byes had'n scared him off so he would."

"And you heard nothing before he tackled you?" Mr. Lakewood asked.

"Niver a bit."

"You think it was a man?"

"Sure an' whot else could it uv bin?"

"How about a big monkey?" Captain Ole asked.

"Well, it moight have bin a monkey but it's me bet it was a man, an' as I said before, ut's the second time. First he hit me wid a nut an' thin he knocks the wind out uv me. Oh, he's got sumpin comin' ter him all right an' don't yer fergit ut."

"Hope I'll be there to see it," Jack told him.

"An' it's some fight yer'll see if yer are," Pat promised him.

"I should have thought you could tell by the feeling whether it was a man or a monkey," Captain Ole said.

"Well, the thing was hairy enough ter be a monkey if thot's whot yer mane," Pat told him.

"And the noise he made sounded more like a monkey than a man to me," Bob added.

"But fer all thot I'm bettin' 'twas a man," Pat insisted. "Sure an' I niver heard yit uv a monkey swimmin' an' thot feller must've swum out here from the shore."

"Well, I reckon he's gone for to-night whatever it was," Captain Ole said. "I'll stay up the rest of the night and the rest of you'd better get back to bed."

"Nuttin' uv the sort. I'll finish out me watch," Pat insisted.

"It'll be light now in about an hour and you'd better get a little sleep after that jolt," the captain told him.

But the mate refused to leave his trick and, after a little more arguing, it was decided that both the captain and the mate would stay up.

"He might come back and it'll take two to watch the boat securely in the darkness," Captain Ole said.

The boys went back to bed but were too excited to sleep and, after talking together for a while, they decided to get dressed and join the captain and Pat on deck.

"So you thought we might need protection, eh," Captain Ole laughed as they joined him on the bridge a few minutes later.

"Not that, sir, but we couldn't get to sleep again and it's mighty hot in there so we thought we might's well call it a night," Bob told him.

"Well, I'm mighty glad of your company anyhow."

The rest of the night passed without incident and, as soon as breakfast was over, the following morning, the anchorage of the Valkyrie was changed to a position about two hundred yards off the north end of the island. Here they found the water but a little more than five fathoms deep and it was then high tide.

"It'll be shallow enough to use the rakes for at least a hundred yards off shore when the tide goes out," Mr. Lakewood declared as the anchor touched bottom.

"Hadn't we better be getting the rakes ready?" Bob asked.

"Sure we will, right away."

He gave the order to a couple of the sailors and they went below and soon returned carrying four of the rakes in their arms. They were about twelve feet long, each rake consisting of two poles bolted together about four feet from one end, which had fastened to it a curved jaw fitted with long teeth. These jaws when shut made a kind of basket capable of holding a peck or more of oysters.

"They're more like a big pair of pliers than a rake," Jack said as the sailors laid them down on the deck.

"But they call them rakes just the same," his uncle told him.

"How soon can we have a try with them?" Bob asked.

"Right away if you want to."

"I'll say we do," Jack declared.

"All right, then, we'll start in near shore where the water's shallow enough to work out as the tide recedes."

"Gee, but I hope they're thick," Jack said as his uncle ordered two of the small boats lowered.

It was quickly arranged that the two boys and their uncle would take one boat while Pat and two of the sailors went in the other.

"The one what gleets the flirst loyster velly slure gleets two pieces of plie for dinner," Wong told them as they started down the ladder.

"You save 'em for me, Wong," Jack shouted back.

"All lightee," Wong told him.

At high tide the water lapped against the cliff and it was not until they were within a few feet of the land that they found the water shallow enough for their purpose.

"All right now, one of you in either end," Mr. Lakewood said as he ceased rowing. "I guess you know how to work the things without being shown."

"Seeing there's only one possible way I reckon we do," Bob assured him.

"Then go to it and remember the reward," he laughed.

"Those two pieces of pie are as good as under my belt right now," Jack declared as he stood up in the bow and lowered the rake into the water. "Gee, but I've got something," he added a moment later after he had opened the rake as wide as possible and then slowly closed it. "I must have a bushel," he continued as hand over hand he pulled in the load.

Jack's rake was nearly full sure enough but, after he had dumped the contents onto the bottom of the boat, he was greatly chagrined to find that he had brought up nothing but stones.

"There's where you lose the pie," Bob taunted as he swung his load over the edge of the boat.

But he too had brought up nothing but stones.

"I'll get that pie yet," Jack laughed as he finished throwing his stones back in the water and lowered his rake a second time.

But for fully half an hour they raked the bottom of the ocean, as Jack put it, and nothing but stones rewarded their efforts. And the men in the other boat had no better luck.

"I reckon we're in too near shore," Mr. Lakewood declared as he noted that the boys were getting rather discouraged. "After dinner the tide will be out and we may have better luck."

"Here's hoping," Jack said as he dumped another load of stones into the boat.

"But let's not give up yet," Bob said throwing the last of his last failure over the side of the boat. "I got a stone that time which looks something like an oyster."

"Then we must be getting warm," Jack laughed.

So for another half hour they persisted working gradually further from the island as the tide receded. Then, just as they were about to return to the ship for dinner, Jack brought up the first shell.

"Hurrah!" he shouted as his quick eye spied the bivalve among the load of stones he had dumped. "I told you that pie belonged to me."

It wasn't much of an oyster, as Bob told him, and there was no pearl in it, but Jack insisted that even so it was worth two pieces of pie.

"And where there's one there's bound to be more," he exulted. Before they had time to try again the dinner gong sounded and, much against their inclination, they had to hurry back.

"We'll fill the boat after dinner," Jack declared as he took the oars and started to row back to the Valkyrie.

Jack got his two pieces of pie and Wong, seeing the wistful look on Bob's face, gave him an extra piece as well.

"You'll have to earn that after dinner," Jack told him.

When they started in again after dinner the tide was more than two-thirds out and a strip of sand showed at the foot of the cliff. They began operations at about the same place where they had left off and, after a few trials Bob brought up the second oyster.

"There, that's a real oyster," he announced as he picked it out from the stones.

"It's big enough to hold a good sized pearl at any rate," Mr. Lakewood smiled as he reached out his hand for it.

With his oyster knife he quickly opened it and, to their great joy, found a pearl about the size of a small pea.

"Not very large but it's a good one," he told them.

"Think it would buy two pieces of pie?" Bob asked.

"You had the pie anyhow," Jack reminded him.

"Well, you can't say I haven't earned it now," Bob retorted with a grin.

It was an hour before they found another pearl although they pulled in one or more oysters with nearly every haul.

"It must have taken whoever covered the floor of that cave some time unless he found them thicker than we are," Jack declared after he had dumped two loads of stones without a single oyster.

"I believe we'll strike them thicker somewhere around here," Mr. Lakewood said. "I think the others are doing better than we are," he added.

"Let's paddle over and see," Bob suggested.

The other boat was some hundred feet distant and the two men who were handling the rakes seemed to be putting a good deal of enthusiasm in their work as Mr. Lakewood paddled toward them.

"How's tricks?" Bob called when they were only a few feet distant.

"Coming in pretty fast now," Pat, who was sitting in the middle of the boat, answered.

"Found any pearls?" Jack asked.

"Six."

"Six?"

"Faith an' thot's whot I said an' here's another," and the mate held up a pearl nearly as large as the end of his thumb.

"You've got us licked by five," Bob told him as the two boats touched.

It was evident that they had struck the bed for, as one of the sailors pulled in his rake, they could see that it was nearly filled with oysters.

"Why didn't you tell us you'd struck them?" Bob demanded.

"Faith an' it's only a minute thot we hit 'em thick. It's meself as was jest goin' ter shout ter yer whin I seed yer comin'."

The boys pitched in with renewed effort and soon had the oysters coming in thick and fast.

"I'll say these are real oysters," Jack laughed as he dumped a rake full of them in the boat.

"If the pearls are there and of a size in proportion we'll be all right," Bob added.

The oysters were now coming in much faster than Mr. Lakewood could open them although he was working as rapidly as possible.

"Here's a good one," he announced soon after they had started work in the new place.

"I'll say it is," Jack laughed. "Just keep 'em a-coming."

They worked industriously until the bell called them back for supper and, as soon as the meal was over, they finished opening the remainder of the oysters, a task which kept them busy until dark. As a result of the day's work they found that they had gathered thirty-three pearls, many of them of good size and three were very large.

"What do you suppose they're worth?" Bob asked as he threw the last of the shells overboard.

"Well, I'm not much of an expert at valuing them but I'd say we've got close on to two thousand dollars' worth."

"You mean it?" Jack gasped.

"I believe it'll run over that amount rather than under it," his uncle assured him.

"But isn't it unusual to find them so thick?" Bob asked.

"Indeed it is. I happen to know that as a usual thing not more than one oyster in a thousand has a pearl in it and probably not that."

"Then what makes them so thick in these fellows?" Bob asked.

"I'm not sure, of course, but, you know, it is thought that a pearl comes from a grain of sand getting into the oyster's shell and setting up an irritation. Now, you may not have noticed it, but these oysters are slightly different from those we're used to not only in size but in shape as well. Their shells are more nearly round and are slightly rougher. My theory is that this kind of oyster, for some reason which I can't explain, is more liable to the pearl disease than any other varieties."

"It's a good theory, I'll say," Bob agreed.

"And let's hope they don't get over it in a hurry," Jack added.

"Get over what?" Bob asked.

"Why, that irritation that makes pearls," Jack laughed.