CHAPTER I.—MYSTERIOUS DISAPPEARANCES.

The motor boat Rambler lay pulling at her anchor-chain in the muddy waters of the Gulf of California. To the North opened the wide, shallow mouth of the Colorado river, with its many shifting currents and treacherous sandbars.

Eastward stretched a Mexican desert, where flourished cacti and forms of animal life unknown to other parts of the world. Beyond this waste of sand, which had, in times long gone by, formed the bed of a lake, rose the peaks and ridges of the Sierra del Pinacates mountains.

To the South the Montague islands shut out the body of the Gulf, and Westward a patch of desert led out to a mountain range. There are two volcanic elevations running down the peninsula, and beyond them lies the tumbling Pacific ocean, a hundred miles away.

The sun was lifting out of the desert to the East, rising round and red and hot, like the bottom of a great brass kettle, and the chill of the dark hours was changing to the stifling, long-scorching heat which is a thing of the desert the world over.

Those who have followed the adventures of the Rambler and her crew, will remember her last on the Columbia. After a journey through the wild canyons and forest-lined reaches of the great river of the Northwest Territories, the motor boat had been shipped to Guaymas, where she had taken to the water again in the Gulf of California.

The Rambler carried a crew of three this morning, Clayton Emmett, Cornelius Witters and Alexander Smith wick, boys of seventeen, who had explored the Amazon as well as the Columbia in the staunch little boat. There had been others on the previous trips, but now only these three were ready for the voyage up the wonderful stream which finds its waters in the frozen snows of the Rocky Mountains and plays hide-and-seek with them thousands of feet below the lips of the desert, in the most mysterious and wildly beautiful canyons known to the world.

Others might join them at up-river points, but the lads were content to make the journey just as they were. Now, as the sun rose higher and the air above the sands began to shimmer in the heat, they tumbled out of their bunks in the little cabin of the motor boat and, after invigorating baths in the Gulf, began preparations for breakfast.

“If we wait much longer,” Alex suggested, as he busied himself in making coffee, “we won’t want anything for breakfast but snowballs, it will be so hot, and we’re not likely to get them in this oven of a land. Who’s going to fry the cakes this morning? Oh, you would, would you!”

This last sentence was addressed to a grizzly bear cub which shambled into the cabin and placed two paws and a soft muzzle of a mouth on the table where the boy stood. This was “Teddy,” the cub Alex had captured during the trip down the Columbia river.

“I know what you want, Teddy Bear!” the boy added, as the cub winked a small eye at him. “You want to wait until I get the sugar out, then you want to empty one bowl into one bear! Now, you move on!”

The boy addressed the cub just as he would have spoken to one of his chums, and the bear appeared to understand what was said to him, for he grabbed angrily at an egg which Alex had brought to “settle” the coffee and made off with it, walking upright to the door, with the broken yolk marking his muzzle, paws and breast with cabalistic inscriptions in yellow.

Once on deck the cub was promptly chased over the rail into the Gulf, where he wallowed clumsily, with three boys laughing at his antics and penitent looks. When permitted to come, dripping and sullen, on board he sulked off to a corner and scolded every one who approached until Captain Joe sat down in front of him and grinned sarcastically at his plastered fur and stuck-up eyes.

Captain Joe was a white bulldog the boys had acquired on the Amazon trip. The bear and the dog were great chums. Captain Joe now sat making wrinkled faces at the disconsolate cub.

“Eat him up, Captain Joe!” Cornelius Witters, known to his friends as “Case,” shouted. “He stole an egg!”

The dog cocked one short ear and looked reproachfully at the cub.

“The price of that egg would have bought you a bone, Captain Joe,” Clayton Emmett, better known as “Clay,” put in. “Take a bit out of him, just to teach him better manners!”

Captain Joe winked his red eyes at Teddy and walked away in a dignified manner, as if not relishing being made the executioner of the crew! The lads laughed at the animal’s attitude of offended innocence and went on with their preparations for breakfast.

The most of the cooking was done on the top of a coal stove, but the coffee was bubbling on an electric coil which stood on a table at the back of the cabin. After a dozen pancakes had been cooked Alex placed them close to the electric coil to keep warm, though, as he said, “The air was fit to keep them red hot anywhere.”

There was a small, square window over the electric stove, at the back of the cabin, a window which opened on about a yard’s width of deck at the stern of the boat. This small space concealed gasoline tanks, and was not in sight from either the deck or the cabin of the motor boat.

Indeed, it was rarely visited, except by Captain Joe and Teddy, who often took long siestas there when the bulk of the cabin cast shadows on the bare planks.

Case cooked heap after heap of brown buckwheat cakes and passed them on to Alex to be placed in the warming closet, as the boys called the ledge of the electric stove, “until they had enough to get a good eating start on,” as Witters observed. Finally he ceased his efforts and glanced at the place where the tempting heap of cakes had been placed.

There was not even a crumb of a pancake in sight! Alex was busy getting out plates and cups, his back to the electric stove and the window. The coffee was bubbling over the cherry-red coils.

Case advanced to the stove and looked over it, under it, around it, and even under the table it stood on. There wasn’t a pancake, or a part of pancake, anywhere! He rushed up to Alex and shook him by the arm.

“You never bolted ’em all?” he demanded. “Not every last one of them, did you? Two dozen of 'em! You never did!”

Alex dropped a plate on the table and looked quizzically at Case.

“Sure!” he declared. “Sure I did! What of it?”

“Two dozen cakes at one gobble!” laughed Case. “Now, you can get ready to cook more. Land of Promise! Twenty-four—count 'em—twenty-four at one mouthful! If I had your capacity I’d—”

Then Alex began to sense the situation. He glanced from Case to the place where the cakes had just stood in a rich, brown column. Then his eyes roved about until they encountered Captain Joe and Teddy consoling each other on the prow of the boat. They certainly couldn’t have done it!

“Did you get ’em?” he asked, hopelessly, of Case? “Did you cop 'em out to prevent our getting indigestion?”

“You ate them yourself!” Case returned, half angrily.

Alex grinned and placed his hands at his lean waist.

“I don’t seem to find ’em anywhere,” he laughed. “Not on me!”

“Then where did they go?” demanded Case. “Who did get them?”

Alex walked to the rear window and opened it. The sash swung inward on hinges, and was not locked, but it rarely was locked. Then he thrust his head out of the opening and looked down on the small deck. There was no one there.

“The old Nick is in the place!” Case cried, presently. “I can smell sulphur in the air! Suppose we get out of this?” he added, as Clay came into the cabin. “This ain’t no place for a Christian gentleman!”

Clay’s eyes sparkled when the story was told to him.

“It is a joke!” he laughed. “You’ll have to get some fairy tale stronger than that to account for a lost breakfast! Come on, now, who got the cakes? Own up, and I’ll fry more. Who is the villain?”

“You may search me,” Alex answered, dropping into slang. “Case handed them to me and I put them on the edge of the electric coil. They’ve gone up in the air, if anybody should ask you! Right up in the air!”

“Who opened the window?” asked Clay, still unbelieving.

“I did,” Alex answered. “There’s no one out there.”

“No one could get on board without being challenged by Captain Joe,” Case suggested. “Even Teddy would make a row and ask questions of any stranger! It is uncanny! I’m beginning to think the Rambler is haunted. Or it may be the locality! Suppose we pull anchor and go on up?”

“Just my idea!” Alex agreed. “When we get a few miles up the Colorado, I’ll cook bacon and eggs for breakfast, and we can have some of the honey Teddy didn’t get his thieving paws on.”

So the boys brought up the anchor, started the motors, and in ten minutes were pushing up the Colorado. The famous river is wide and shallow at its junction with the Gulf of California, and the constantly changing currents heap sandbars to-day where there was deep water yesterday, so the lads proceeded at less than half speed.

At the end of an hour they were only fifteen miles from the anchorage of the night before. The river was narrowing. To the east a low line of sand hills came down to the water, to the west the foothills of the Sierra de los Cucapas range dropped close to the channel. Something less than one hundred miles to the north was Yuma, where the Southern Pacific Railroad crosses the stream.

The lads cast anchor near the west shore, and Alex brought out the bacon and eggs, while Case proceeded to brew fresh coffee. By this time the sun was shining blisteringly on the deck of the motor boat, and all three lads were in the cabin, with all the small windows open to the slight breeze.

“Now,” Clay suggested, as the three sat at the little table in the center of the cabin, two facing each other and one looking out of the open doorway which commanded a view of the deck, “suppose we have the honey we’re going to consume to keep Teddy from acquiring it? Where is it?”

“I put it back of the electric stove, there by the window,” Alex replied. “I’ll get it in a minute.”

Three faces were turned toward the rear window, three pair of eyes expressed amazement, incredulity, three boys sprang to their feet and moved toward the electric stove. The can of honey was not there!

“I saw it not more than a minute ago!” insisted Case.

“So did I,” Alex agreed. “Not half a minute ago!”

Then three faces turned toward the deck. Teddy and Captain Joe lay on the prow, sweltering in the heat, their ears cocked as if set to catch some sound as yet only faintly heard. They didn’t have the honey!

“I reckon,” Alex observed, “that we’ve got a phantom boarder!”

“He’s got his nerve, whoever he is!” Case said, with a scowl, for Case was inordinately fond of honey, and had counted much on the can which had so strangely disappeared. “He’s clever, too!”

Captain Joe now arose from the deck at the prow and walked to the railing on the port side. He stood there an instant, as if undecided what to do next, then lifted his paws to the top of the deck guard and looked over into the river.

“I guess the dog’s got him—this phantom boarder!” Clay laughed.

But Captain Joe went back to the cub in a moment and lay down again. If there was any stranger around the boat, the dog certainly was not aware of the fact, the boys concluded. Yet some one had taken the cakes and the honey! Who could it have been, they asked each other.

“It wouldn’t be right for us to start on a river trip unaccompanied by a mystery,” laughed Clay. “We had a mystery with us while we were on the Amazon, and the Columbia panned out pretty well in that particular, too, so I’m not much astonished by the presence of a mysterious boarder now. He ought not to take the best of everything, though,” he added, with a grin at Case, who was still inconsolable because of the loss of the honey.

“Say,” Alex exclaimed, presently. “This is no joke! There’s something going on here that we ought to know more about. The pancakes and honey never walked off without legs! Some fierce creature may have come up out of the river and grabbed them, but I don’t believe it.”

“Do you think there’s some one hidden on the boat?” asked Case. “If there is, where is he? No place to hide here, that I know of.”

“I don’t know anything about that,” Alex returned. “No one from the shore took the two articles of food, for they were taken at points fifteen miles apart—unless we have been visited by two thieves using the same methods, which I do not believe.

“I’m going to find out whether human hands took the grub, or whether some monster came up out of the river and assessed us for a square meal. You boys stay here and watch in front, and I’ll climb on the little deck over the gasoline tanks and see what’s going on there. If anything I can’t handle shows up, I’ll call for help!”

Clay and Case sat for a long time with their eyes fixed on the open deck and the up-river landscape. They heard Alex scramble over the low cabin roof and take a position on the narrow space over the tanks. Then all was still save the rush of the water. Captain Joe arose again, sniffed at the port rail, peered over into the water, and gave a low growl.

“He sees something!” Clay cried, excitedly.

Case hastened to the rear window and looked out, as if to ask Alex a question. At first he only looked out. Then he leaned out. Then he dashed out of the cabin and called to Clay, a note of anxiety in his tone.

When Clay reached the deck he saw what had excited his chum. Alex was not on the narrow deck, not on the cabin roof, nowhere on the boat! The river ran away smooth and clear, sparkling in the light with no craft in sight. The boy had disappeared as utterly as if he had been dissolved in the hot air!

CHAPTER II.—TEN THOUSAND DOLLARS REWARD.

When it became certain that Alex was not on board the Rambler, Clay and Case hustled the small rowboat which lay on the cabin roof into the river, threw in the oars, and cast off the rope.

If Alex was not on the boat, they reasoned, then he must have fallen into the water! It had been at least ten minutes since he had left them to visit the aft deck, and one might float a long way down stream in that time! The wonder was that he had not cried out when he fell!

Case rowed with all his strength, doubled by the excitement of the time, and Clay sat in the prow watching the river ahead. Now he thought he saw a head bobbing on the waves; now he called out that he had caught sight of the boy clinging to the shore; now he shuddered at sight of a clogging mass in the bottom of the stream.

They called out at the top of their lungs as the rowboat went swiftly down with the current, but there was no answering cry. Only when the bulk of the Rambler seemed indistinct and far away through the shimmering sunlight did they turn the prow up stream. Clay was the first to speak after that.

“I don’t believe he ever fell into the river!” he said. “Captain Joe would have heard the splash, even if we did not, and would surely have jumped in after the kid. Besides, Alex would have let out a yell if he had tumbled in, and we should have heard that. He never fell into the river, I tell you!”

“Then where did he go?” demanded Case. “I hope yon haven’t any idea that he went up in the air! Or that he’s hiding to bother us?”

This last sentence expressed a new hope. The boy might be hiding in some odd corner of the boat! They resolved to find out about that as soon as they got aboard again. If he was hiding, well!

They did not carry out the thought, for they were now near enough to the Rambler to see that she was slowly, jerkily moving toward the west shore.

“Did you pull up the anchor?” Clay demanded of Case.

“I should say not,” was the indignant reply. “What for should I do that, I should like to know? Sure you fastened the chain right?”

“Of course! The chain was all right when we left there.”

“Then why should she be moving toward the shore? She’s being towed, or I’m not an inch high! What do you know about that?”

The Rambler was indeed moving toward the west bank of the river! The motors were not in action, and yet she was moving, slowly yet steadily, to the west! In a moment, as they rowed nearer, they saw that she was drifting down toward them, but was, at the same time, being drawn in toward the bank. There was no one in sight on the deck or in the open cabin!

“This must be a fairy land!” Case grumbled. “There’s something uncanny in the very air! How do we know that we are in the Colorado river, anyway? We haven’t seen a ship, or a launch, or a rowboat, except our own, to-day! Things disappear from the cabin, Alex goes up in the air, and now the Rambler wiggles off without any motive power showing!”

“Look at Captain Joe!” shouted Clay. “Just look at the fool dog?”

Case continued to pull at the oars, anxious to gain the Rambler.

“What is he doing?” he asked, not turning around to see.

“He’s barking and snapping at something that doesn’t exist!” Clay replied. “He is fighting with the air—and getting the worst of it!”

“Keep your head, chum!” Case grinned. “Keep on trying to think! The worst is yet to come!”

“Turn around and look, if you don’t believe me,” Clay shouted.

Case turned about on his seat, letting the oars lie idle in the waves for a moment, and fixed his eyes on the deck of the Rambler, now not more than a hundred yards away. Captain Joe was barking like mad on the deck, advancing to the west rail, as if pursuing some one, and then retreating, as if being beaten back!

While the boys looked, he crossed the deck half a dozen times, snapping and snarling at something not in view from the small boat. Whenever he retreated he seemed to be cringing as from a blow! The boys looked on in wonder and fright. The dog was fighting the air!

“Not a thing in sight!” Case commented. “A boat sliding along with no one near her, and a dog barking at nothing at all. I give it up!”

“Let me row,” Clay suggested. “You must be getting tired.”

Case dropped off the seat backward and Clay took up the oars.

“Tell me what you see,” asked the latter, after rowing a moment.

“The dog has gone back to his corner,” Case reported, “and Teddy is doing the investigating. The Rambler is still jerking in shore, and there’s not a soul in sight! Ever hear of invisible men and things? Well, that’s just what we’re up against!”

“Alex is invisible, all right!” grunted Clay. “See him yet?”

Case did not answer. Instead he dropped into the seat beside Clay, almost overturning the frail boat before he succeeded in getting into action with one of the oars. It was a minute before he spoke in explanation of his conduct.

“Pull!” he cried. “Pull for your life! There’s some one at the prow of the boat, pushing her toward shore, and there’s men behind the sand dunes on the west bank, waiting for her to land! We’re up against a nest of pirates, I take it! Pull! We must get to the Rambler before it touches the bank, for the fellows there will swarm over her then.”

And the lads did pull, with all their might. The current of the Colorado is not strong there, and so they made good headway. When they came within fifty yards of the Rambler, she was within that distance of the shore. The men who had been hiding behind the hills a moment before now came out and called sharply to some one on or about the Rambler to make haste and bring her in. There was no verbal answer, but the boat moved faster toward the shore.

Dripping with perspiration, panting in the hot air, the boys put their strength to the oars and finally sprang over the railing just as two of the men entered the water to swim out. They did not draw back when they saw the boys aboard, but swam rapidly on.

“The motors!” shouted Clay. “Get them in motion!”

Case hastened to comply, and Clay dashed into the cabin and returned with a couple of automatic revolvers. Without speaking he fired a shot over the head of the nearest swimmer.

“Missed him!” cried Case. “Let me try one!”

“Get under motion!” insisted Clay. “When you get under way, drop down stream! We’ve got to find Alex, dead or alive!”

A rowboat now shot out from the shore, manned by two men. First the swimmers were picked up, and then the boat was headed for the Rambler.

“Keep off!” Clay called out. “I’ll shoot if you come nearer.”

“In the name of the law!” called one of the men in the boat.

“Never mind the law!” Clay answered. “If you don’t want to get bored through with a forty-five, keep away from the boat.”

“I’ve got to come aboard!” was the answer to this.

“And I’ve got to keep you from doing so!” Clay answered. “We are not interfering with you, or with the laws of Mexico, and we have no notion of spending a few months in a Mexican jail while you people dispose of our boat and our supplies. Keep off! I’ll shoot if you come a foot closer. What have you done with the boy you took off the Rambler?”

Case looked up from the motors with a hopeful smile. Perhaps that was the solution of the puzzle! These men might have in some way stolen the food and taken Alex away. This thought was more cheerful than the one that the boy had fallen into the river and been drowned.

The roar of the motors drowned the answer, if, indeed, any was made. As the propellers swung into motion two figures separated themselves from the prow of the boat, where they had been clinging, out of sight, and struck out toward shore. Clay called to them to stop, but they paid no attention to the command. Directly they were taken into the rowboat. Clay smiled as he took in the situation.

“It is easy now,” he shouted. “Those men were evidently diving and shifting the anchor shoreward, being unable to break the chain, and being afraid to go on board. Guess they know nothing about motors, or they’d have had the Rambler miles up stream long before this!”

The Rambler now struck out for the Gulf, traveling at a swift pace. If Alex had indeed fallen into the stream, they might yet be able to save his life, as he was a strong swimmer and resourceful. The men in the rowboat followed on, losing ground, but persistent. At last Clay halted the boat and called back to them:

“What do you people want of us?”

“Just a little talk,” was the reply, shouted over the water.

“You tried to steal the boat!” Case shouted back. “You’re thieves!”

“Not thieves! After thieves!” came the sharp reply.

“Are you officers?” demanded Clay.

“Officers! American officers!” was the unexpected reply.

“They’re faking!” Case cut in. “You saw how they tried to steal the Rambler! I’ve a notion to take a shot at them.”

Clay swung the Rambler in a circle and came close to the rowboat, an automatic ready for use. Case looked on with disapproval showing in his face.

“Now, what do you want?” Clay demanded, as one of the men arose in the boat. “I’m not running away from officers, if I know it, nor am I holding any extended talks with boat thieves. What do you want?”

“I want to come aboard,” was the stern reply.

The man who spoke was tall, slender, black of hair and eyes, and with a grace and freedom of movement which told of life in the open air. Clay rather liked his looks, and so consented for him to board the Rambler. Case stood by with a revolver to see that no rush was made as the other vaulted easily over the railing after scrambling lightly up the side of the motor boat. But there was no need of this, for the others sat stolidly at the oars, even backing off as the prow bumped the Rambler’s side.

The man who had boarded the Rambler stood for a moment with his hands outstretched, to show that his intentions were not hostile, and then gave a keen look about. It seemed to the boys that he took in every minute detail of the craft, from the bristling dog at the prow to the electric coil at the back of the cabin.

“I’m Joe King,” he finally said. “Joe King, of Arizona. Phoenix, Arizona, to be exact. I’m a deputy sheriff. Where’s the sawed-off kid who came aboard your boat just after dark last night?”

“No one came aboard last night,” answered Clay, half angrily.

“Short, light weight, freckled, red-headed, quick in his talk,” the deputy described. “Where is he? No foolishness, now. I want him.”

“You may have him if you can find him,” grinned Case. “We don’t know any such boy. If you’re lucky finding boys,” Case continued, “I wish you’d find Alex Smithwick! He evaporated half an hour ago.”

Joe King, of Phoenix, Arizona, looked at the two boys doubtfully. He seemed to think they were joking with him. Clay saw that he was not an enemy, and briefly told the story of Alex’s disappearance, also of the vanishing of the honey and cakes. King looked about the boat again.

“Isn’t he hidden somewhere?” he asked, with a sweep of the arm.

“There is no place he could hide,” Case answered. “You were on the shore with your men,” he resumed, “did you see any one leaving the boat?”

“We caught a view of the river only a few moments ago,” was the discouraging reply. “If he has been gone half an hour he might have gone away with a brass band without our knowing it. But here’s a bigger puzzle,” King continued, “and that is where did this Don Durand go to? He sure came on board your boat last night at dusk, while you lay farther down. If you find him, you’ll find the pancakes!”

“We never saw him!” Clay exclaimed. “He might have taken the food, but he couldn’t have taken Alex. What do you want of him, anyway?”

“Why,” was the unexpected reply, “this Don Durand stole a matter of fifty thousand dollars at Chicago. He is a much-wanted boy just at present. Ten thousand dollars reward, you know!”

“How did a boy manage to get hold of so much money?” asked Clay, his eyes large with astonishment.

“He was a bank errand boy,” answered King, “and walked off with a handbag a customer of the concern, one Josiah Trumbull—entrusted to his care. He has been chased all through the west, but has never been taken.”

“And he came on board the Rambler at dusk last night?” asked Case.

“So my men say. They were watching your boat at that time, thinking it might be the home of the thief. I have thoughts running in that direction right this minute! So you’d better give an account of yourself.”

Clay, seeing that the deputy was sincere and friendly, told the story of past and prospective trips. King listened with amused eyes.

“All right!” he said. “I’ve heard of you boys! You caught a robber up the Columbia and got a rich reward! Hope you’ll get another one right here. But this Don Durand is a clever chap, though only the size of a pint cup! He’s so small that he may be hiding here right now.”

“I’m glad he got something to eat!” Case exclaimed. “I’ll bet he was hungry! You don’t think he coaxed Alex off, do you?”

“Did he have an airship or a diving bell to take him off in?” laughed King. “He has the price of both, I take it, for the papers say he is carrying fifty thousand in gold notes around with him.”

“Alex might have found him out on the aft deck and chased him off, and then followed him,” Clay suggested. “Alex is a pretty good swimmer,” he added. “He wins medals in under-water endurance tests!”

“Now you’re beginning to think right!” King commented. “The boys may be on shore. If they are, my men will get them. And I reckon they’re putting up a fight right now,” he added. “Hear the shots?”

Puffs of smoke lifted over the hills, and then a rattling volley came from the mountain spur not far to the west.

CHAPTER III.—CAPTAIN JOE’S MESSAGE.

Deputy King stepped over to the deck rail and looked down at the rowboat in which he had left the shore. It held five men, all dusky, uncouth looking fellows, with greasy hair and black, suspicious eyes. One of the men had left the shore with the deputy, two had been picked up in the river on the way out, and two more had been taken in when the rowboat came closer to the Rambler.

These last two were the ones who had been working the motor boat toward the shore by diving and lifting the anchor and putting it over. As the craft always swung over to the new anchorage, she had gained the shore by just the distance the anchor had been moved.

It was known afterward that the men had been sent out to board the motor boat and bring her in, but that they feared armed opposition from concealed occupants, and so resorted to the slower but safer, if laborious, method described. When King looked down upon the boat all five occupants were actively engaged in getting under way, four handling oars and the fifth at the helm. They were already a couple of yards from the motor boat.

“Here!” cried King. “Come back with that boat! What are you doing? That firing doesn’t mean anything to you! Come back!”

The five men laughed insolently, and one of them made significant and insulting gestures with a thumb at his nose! The boat shot swiftly toward the shore, leaving King fuming on the deck of the Rambler.

“Nothing stays put in the vicinity of the Rambler!” laughed Clay. “I reckon those are Mexicans, and that they are frightened at the firing.”

“They are Mexicans, sure enough!” King replied. “But they are not running away from the shooting. They are going to it!”

“Not going to fight for the fun of it?” asked Case.

“They are deserting me and going back to their friends,” King said. “They now hope to capture the boy without my help, and so get all of the reward, as well as running off with the good money I paid them to assist me! I presume they think the men over in the mountain spur have found the boy and are shooting at him. Why, he’s so small they’d have to use a telescope to see him at that distance! Anyway, I’m done for, with this desertion, and may as well take passage with you to Yuma.”

“You’re welcome to go with us,” Clay answered, “but we’re not going on until we find Alex. And if he gets tangled up with the Greasers on shore we’re going after him. We won’t go on without him!”

“Of course not,” agreed the deputy. “Well, I’ll remain here as long as you do. I may still stand a chance of getting that reward. Suppose you put more pancakes and honey on the table back of the electric stove!” he added with a sly wink. “He may come on board right away, then!”

“Pancakes will also bring Alex on board,” laughed Clay. “He’s got the appetite when it comes to pancakes and honey! Never saw a kid eat so many cakes as Alex can stow away! He’s almost as empty as Teddy Bear.”

“That the cub yonder?” asked King, pointing to the prow, where Teddy and Captain Joe lay asleep in the sunshine, apparently beyond all the cares and worries of a wicked world. “Clever dog, that!”

Captain Joe, as if conscious that he was under observation, arose, stretched himself, and walked over to the rail, where he stood sniffing at the air. Then, with his nose pointing straight toward the shore, he uttered a series of excited growls.

“He knows that Alex is there,” Case cried. “Go and get him, Captain Joe!” he added, and the next instant the dog was in the water.

“You’ve done a nice thing now!” Clay exclaimed, gazing angrily at Case. “The dog will be shot before he gets within a rod of the shore.”

“I never thought of that!” Case replied, regretfully.

The boys tried to call the dog back to the boat, but he swam on, paying no attention whatever to their threats and promises! Clay turned to the rail where the little rowboat had been tied, thinking to follow him in that, but it was gone! Before setting out for the shore, the Mexicans who had deserted King had cut it loose, and it could now be seen a long distance down the river, bobbing about on the twisting currents.

“I’m going after him anyway!” Clay shouted, rushing to the silent motors.

It was Deputy King who checked his ill-advised determination.

“You can’t get anywhere near the shore with the motor boat,” he said. “It is so shallow a few yards from here that the rowboat just barely floats. Will the dog go straight to Alex as you call him?”

“He will if he is not interfered with,” answered Clay, moodily.

“Then we’ll watch the dog,” King went on. “Do you know, kids, that I have a hunch that this Don Durand, the thief, is with Alex? I believe they left the Rambler together. I don’t know why, or when, or how they first came together, but that’s the hunch, and I can’t get it out of my mind.”

The Mexicans who had deserted the deputy were now landing on a low, sandy stretch of beach, back of which ran a natural levee of sand, perhaps six feet in height. Beyond that, and only a few hundred paces from the water’s edge, a spur of the foothills ran out to the east.

The Mexicans saw the dog swimming toward them and deployed on the beach to capture or kill him. This was, perhaps, the very best move they could have made in the interest of the boys, for Captain Joe sensed danger and turned south, swimming swiftly down with the current.

The Mexicans bred a dozen shots at him and then turned their attention to a commotion in progress between the sand levee and the mountain spur. The men who had fired from the foothills were advancing across the level, and the men who had been left on shore by King were lined up to meet them. Those on the Rambler could not see what was going on, but, presently a crowd of Mexicans came out on the beach, as if to keep watch of the Rambler.

“I’d like to know what the mischief is going on there,” exclaimed Case, as Captain Joe, already far down stream, crept out of the water and trotted out of sight, after looking back over his shoulder to see that no guns were pointed at him.

“I think I can tell you what’s going on,” King suggested. “The men I left there have come to terms with the native Indians, who are always ready for a fight or a race! It looks bad for us!”

“I don’t understand,” Clay ventured. They have nothing against us.”

“Yes they have,” King went on. “You have a fine motor boat, and the Mexican Indian always has something against a fellow who has something he wants himself. What you ought to do now is to run upstream at full speed, so as to head off any canoe blockade which may be forming.”

“And leave Alex here?” demanded Case. “I should say not!”

“Then drop down to where the dog left the water,” advised King. “You see,” he explained, “I’m still believing that Don Durand is with Alex, and I’m taking chances on the dog finding the boy.”

“He will if Alex is there,” Clay observed, confidently. “I only hope the kid is there,” he added, turning on power and dropping down stream.

There was a little sand island—one of the kind which lift above the water one day and sink down the next—just below where Captain Joe had taken to the shore, and here Case left the Rambler, resolved to make his way to shore along a spit of sand which almost joined the beach with the island.

Both Clay and the deputy objected strongly to his going, but he promised to keep close to the boat and to take no needless risks. The boy bent low as he crossed the strip of beach, desiring to keep out of sight of those above if possible.

“I wish I had gone with him,” King said, as Case disappeared over the sand hillocks. “He may come across the boys, but find himself unable to bring Don Durand back with him.”

“Does the boy know that the search for him is on here?” asked Clay.

“Oh, he knows, generally, that officers are in pursuit of him,” was the reply. “He is hiding in all kinds of out-of-the-way places. Without doubt he slept on your aft deck last night, and breakfasted off pancakes and honey!” the deputy added, with a provoking grin. “And you never knew he was there! He must have been hungry.”

“Then I’m glad he got the pancakes!” insisted Clay. “He was welcome to them, and might have had a softer bed last night, if he had only made his presence on the Rambler known to us. How long ago was it that he took this money?”

“Oh, somewhere near a month ago,” was the reply. “He has given the officers a great chase, if he is a mite of a fellow.”

The Rambler lay off the sand island, and close to it, for the water was deep on one side, for an hour before any movement was seen on shore. The Mexicans above had evidently taken shelter from the scorching sun, believing that they would be able to intercept the boat if she started up stream, for no one was in sight on shore opposite the old anchorage. It was very hot on deck, and King and Clay sought the cabin, resolved to there await some signal from Case.

Presently Captain Joe’s head showed above the natural levee, and then the body of the white bulldog lifted over the elevation, shot swiftly to the water line and swam off to the Rambler, Clay and the deputy watching to see that he was not followed from the shore.

“Now, what do you think that means?” Clay asked, as Captain Joe gave the deck a liberal sprinkling and took his place in front of the boy, regarding him with watchful and anxious eyes. “He wants something.”

“He wants us to go ashore with him,” King interpreted. “He’s found the boys, and they are in trouble. Now, what about leaving the boat?”

“We might as well make the Mexicans a present of it,” Clay answered.

“That’s true!” King replied. “Well, you can do more with the boys and the dog than I can, so you would better go with him. I’ll do the best I can to defend the Rambler, if an attack is made.”

Clay was uncertain as to the correct course to pursue. While he did not doubt the honesty of the deputy sheriff, he realized that he was out in quest of a fugitive for whose arrest a large sum of money was offered. The boy understood that the officer would adopt almost any selfish plan that promised success to his official undertaking.

He believed that he would even requisition the Rambler and sail away with it if he should by chance find, or get, the fugitive on board during the absence of the owners. There would be need of his sailing away instantly, too, for the Mexicans were reckless and vicious, and out after the same reward!

Just how King might get Durand on board during his absence he had not the slightest idea. In fact, he considered such a thing as utterly impossible, and yet he found himself actually considering such a possibility in reaching out for reasons why he ought not to leave the Rambler in the sole charge of this stranger.

Clay knew that there was always a chance that Durand, pursued by the Mexicans, might make for the motor boat, not knowing the conditions existing on board. Still, it was so remote a chance that he smiled as he considered it. But something had to be done.

Captain Joe’s return, his attitude, told of trouble ashore. If all had been well with the boys, one or all of them would have accompanied the dog to the motor boat. Clay decided to take the one chance there was of losing the Rambler—the only chance there was if King was what he professed to be. The boys demanded his whole attention.

“There’s only one thing I want to say to you,” King said, as Clay lowered himself over the rail. “If you find this Durand boy with the others, just bring him along with you, and say nothing about my being on board. If you get him here, you shall share the reward.”

Clay made no promise. He was more than disgusted at the course events were taking. Instead of sailing, care-free, up the river, as had been planned, his chums were in some trouble of which he knew nothing on shore, and he was leaving the Rambler in the charge of an entire stranger.

Besides, on their very first day on the Colorado, they had become entangled in the meshes of a crime committed in Chicago more than a month before, and the boy had had enough of crime on his previous river trips!

Just now, his chief aim was to get entirely away from civilization. He wanted to get his friends together once more, get rid of King and all that he represented, and proceed to the wonderful sights to be found on the river. He wanted to lose sight of everything save the original purpose of the trip. He had had enough of mixing with others’ affairs!

He gained the shore without getting more than his feet wet and crossed the tide-washed stretch of sand to the natural levee. Looking back, he saw King tinkering with the motors, and was seriously inclined to return to the Rambler. But Captain Joe was urging him on with all the arguments known to a white bulldog, so he crossed the string of sandy barrier and set out for the spur which ran down from the foothills.

There was no one in sight, either up or down the river, and his idea was that the Mexicans had deserted the position opposite the old anchorage. Either that, or they were in hiding ahead, waiting to seize him.

Finally Captain Joe deserted him, wandered off unobserved into one of the wrinkles in the hills. He could not understand this at all, for the dog should have continued to lead the way to the source of trouble he had returned to the Rambler to report.

For a moment Clay considered the advisability of returning at once to the motor boat. The sun shone out of the sky like a blazing ball of fire, and the sands were hot and blinding. As far as he could see, up and down the river, there were no evidences of human life in sight save only the Rambler, lying on a stream which seemed to Clay to have a right to boil with the heat which surrounded it.

But Clay hated a quitter as much as he hated a coward, and so kept on toward the glaring foothills which lifted straight away to the west. Then voices to right and left told him that he had been trapped!

CHAPTER IV.—“THE PHANTOM BOARDER”

When Alex climbed over the top of the motor boat’s cabin for the purpose of investigating the mystery of the disappearance of the cakes and honey, he saw a dripping lad much smaller than himself sitting close under the open window composedly devouring the pancakes and honey! So great was the haste, or so imperious the hunger, of the boy that he was cramming the cakes into his mouth as if stuffing them into a bag!

In the sheltered position in which he sat he could not be seen from the inside of the cabin, even by one glancing through the open window, unless the person so investigating should thrust his head far out of the opening. He was crowded up against the rear wall of the cabin, in a small pool of water which had trinkled out of his soaked garments. It was evident that he had not long been out of the river.

Alex, lying flat on his stomach on the roof of the cabin, reached down a hand in an attempt to seize the intruder by the hair of the head. Now that he had discovered the purloiner of the breakfast, he was bent on dragging him, a captive, before his chums—with what was left of the cakes in sight!

But the boy did not reach down far enough. Instead of grasping the rusty red hair of the visitor, he merely seized a flat, postage-stamp cap which illy protected his head from the rays of the sun. The lad felt his cap lifting and, thrusting the cakes, covered with honey as they were, into a pocket of his trousers, looked up to see Alex grinning down at him.

To this day Alex insists that he then saw the quickest human movement of his life. One instant the intruder was sitting on the narrow aft deck stuffing pancakes into his mouth. The next he was under water, swimming swiftly down with the current! Alex saw only a twinkle of wet shoes and dripping stockings and the lad was gone!

The boy watched the thief for only a second. Without stopping to warn his chums, without considering the risks he was running, he foolishly sprang down on the aft deck and dove headfirst into the river. It was little wonder that the unusual proceedings at the stern of the boat failed to arouse Captain Joe, for in a minute the boys were under water and far down stream.

About the time Clay and Case were looking for their chum, Alex was, in close pursuit of the pancake thief, crawling out of the river some distance below at a point, in fact, where a sprawling island of sand was almost connected with the shore by a long spit! Before the searchers climbed over on the aft deck, the hot sun had completely evaporated the water the intruder had brought there in his garments, so there were no traces of his ever having been there at all!

Reaching the shore, the fugitive dashed across the tide-leveled beach and sprang lightly over the levee. Alex came, panting, after him, for the swim had been a long one, to meet with the surprise of his life when he half climbed, half tumbled, over the shifting elevation.

The fugitive seized him as he dropped, turned him over by a deft and powerful movement of hands, arms and body, and promptly sat down on him, holding his arms down on his breast! Alex was practically helpless, although his assailant was much smaller than himself, and panting, too, from the same long swim—mostly under the reddish brown waters of the river. He was not long, however, in realizing the humor of the situation, for he looked up into the freckled face above him with a grin.

Now, Alex’s grin was an alluring thing! He had conquered enemies with it, and secured more than his share of Christmas presents at free distributions in Chicago, when he was still a little tot. The victorious thief “fell for it,” as he would have expressed it, and gave back one that was very much like it!

“What’s doing?” Alex demanded, in a moment.

“What do you mean by spoiling my breakfast?” demanded the other.

Alex roared as heartily as was possible, considering the restrained position in which he found himself. It was too funny!

“Your breakfast!” Alex exclaimed. “You’ve got your nerve! My breakfast! You’ve got your appetite with you, too, if you ate all you stole through the cabin window! You must have been hungry!”

The stranger bounded off Alex and sat down on the sand, keeping a watchful eye on his late prisoner, however. Alex rose to a sitting position and grinned again. The other took a pancake from his pocket and began eating. Alex looked on and wondered at the appetite!

“Does it taste as mussy as it looks?” he asked, referring to the pancake, which looked like a mass of brown dough dripping with honey and crushed into odd shapes by soiled fingers.

“It tastes like something to eat!” was the reply. “Say, but I was about starved to death when I smelt the pancakes. If I’ll go back on board, will you cook me some more? I’m still hungry!”

“Sure I will,” replied Alex. “What did you run away for?”

“You haven’t heard?” demanded the other, suspiciously.

“Haven’t heard what?” asked Alex.

The other looked out to the foothills and back to the levee, which concealed the river from view. Then he searched his pocket for another pancake, failed to find it, and rolled along on the sand.

“Haven’t heard what?” asked Alex, determined to know what the other was driving at. “What haven’t I heard? What you mean by that?”

“What’s your name?” the stranger asked, abruptly.

“Alex Smithwick,” was the quick reply.

“I’ve heard of you,” the other went on. “Some Chicago newspaper printed a picture of the Rambler and you three boys. That’s how I found the nerve to visit you last night. I’m from Chicago. I was looking for you!”

“Tell me what it is I haven’t heard,” Alex insisted, “and tell me your name! I’ve told you mine.”

“I’m Don Durand,” was the quick reply. “I guess that will tell all there is to tell. Guess you’ve heard that name before!”

“You ain’t ever been president of the United States, or lightweight champion, or the jockey that won the derby, or anything like that, have you?” Alex asked, whimsically. “If you have, I’ve overlooked a big one, for I never heard that name until just now! Unravel your crime, me son!” he added, with a grin which brought out all the freckles in his friendly face.

“It is a crime, all right!” Don admitted, hanging his head.

“I didn’t know it!” Alex cried, distressed at the other’s humiliation. “If I had, I wouldn’t have said the word. If you don’t want to talk about it, you needn’t.”

“I want you to know,” Don answered. “I’ve just got to tell some one, or I’ll bust! I’m a thief!”

“Pancakes and honey?” asked Alex. “I knew that before!”

“No; money,” the other went on. “A whole lot of money!”

“Huh!” Alex observed, looking over the hot sand, the hotter hills, the brazen sky, and the starved landscape, “did you come down here to serve out your sentence? Strikes me that you’d better be in some nice cool jail, where there is plenty of pancakes and honey!”

“I’ve stolen about all the money there is in the world!” Don said, in a moment, a troubled look coming over his face.

“Have you got it yet?” asked Alex.

“Every cent of it!” was the reply. “Every last cent of it!”

Don threw off his wet jacket, loosened his waistband, and, after working both hands in the vicinity of his hips for a moment, making wry faces every second of the time, drew forth a waterproof belt the bulging sides of which proclaimed crowded contents. After shaking it to remove any chance drop of water, Don unfastened the buckles and began unwinding the oiled silk which enclosed the contents of the belt.

Directly the long wrapping lay on the sand at the boy’s side, and the burden of the belt lay revealed. Alex’s eyes bulged out so they ached.

The waterproof belt had been stuffed with money—gold treasury notes of the denomination of $1,000!

“Wow!” Alex exclaimed, almost involuntarily. “Talk about wealth! There it is! How many of those picture cards are there?”

“Fifty!” was the quiet reply. “I stole $50,000.”

“That’s nice!” grinned Alex. “Are you going abroad to buy a little kingdom with it? Standard Oil hasn’t anything on you!”

“I’m going to give it to the owner,” was the unexpected reply.

“Well, why don’t you, then?” asked the boy.

“Because I don’t know where he is. He’s lost!”

“You knew where he was when you stole it from him, didn’t you?” asked Alex. “Why can’t you go find him?”

“I didn’t steal it from the owner,” was the reply. “I stole it from the man that stole it from the owner.”

Don, exploring the belt, brought out two slips of paper, read them over hastily, and crushed them back into the secure cavity again.

Alex did not ask what the quick action meant, for he was busy with the gold notes. He had never before seen so much money at one time in his life. It seemed to him that all the wealth of the world lay exposed on the hot sand at his feet. Don regarded it carelessly.

Presently Alex took the notes into his hands and began counting them. He placed them in little heaps, then he laid them along the sand, end to end. He was interrupted in the midst of this fascinating employment by a low cry from Don.

“What is it he asked?” gathering the money up in one heap, preparatory to concealing it. “Some one coming?”

“Some one peered over that sand dune,” Don answered. “I saw eyes like a snake’s feasting on the money! I shouldn’t have taken it out in an exposed place like this. What shall I do with it?”

Alex’s resourceful mind was not long in finding a way.

“Grab it up,” he directed. “Make as if you were putting it back in the belt, but pass it to me, with the silk, and I’ll bury it in the sand. Here, put plenty of sand in the belt, so it will look like it was still full of money. Now, put it on! Turn so any one watching us will see you doing it. They’ll think you're hiding the money in the belt again, but we’ll fool ’em!”

Don did as directed by the quick-witted lad, and then Alex started away toward the river, walking as if he had no idea that there was any one in the world besides himself and friend. He smiled as he turned to his companion, whose eyes were fixed intently on the location of the silk covering which held the treasury notes.

“Think I’m going to cut and run with the mazuma?” he asked, following the other’s gaze back to his own wet clothing.

“Why—why—of course not,” faltered the other. “Why should you?”

“I’m going to hide it in the sand, and take bearings so that either of us can find it,” Alex went on. “This neat little bunch of spinach is not for the Greasers! It might be their ruin!” he added, with a grin. “It might drive them to drink!”

“But the tide and the current may wash that sand away, or shift it about, within the next twenty-four hours,” urged Don, with a sigh.

“That’s true!” Alex admitted, with a worried look. “That’s true. We are now up against the responsibilities of great wealth!” he continued, with another whimsical grin. “Do you see the Greasers watching us yet? They mustn’t suspect that the belt is empty of cash!”

“One of them peeped over a rise just as we started away,” was the reply. “They’re watching us, all right enough. They smell money?”

Alex threw himself down on the sand, in a position which overlooked the river, and rolled about in exaggerated ease. Don sat down close at his side, and the money was buried between them.

“See that bald old peak across the river?” asked Alex, when the job had been satisfactorily completed. “And that topknot to the west?”

“Sure I do!” Don replied, still watching the spot where the money had been placed, and looking as if he would like to dig it up again.

“Well, when you want this cash, just come to the top of this barrier and dig on a straight line between the two. Then you can’t miss it.”

“Unless the water gets here first!” Don grumbled.

“It is risky,” Alex admitted, “but if you keep it in the belt the Greasers stand a show of getting it, so where’s the odds? Just now they think you’ve got the money on your person, and so, considering it safe for the present, they won’t be in any hurry about attacking us. That gives us a chance for our lives, anyway, though they’re pretty sure to come after us before long.”

While the lads lay watching the river, and wishing themselves aboard the distant Rambler, three ferocious-looking fellows crept upon them, moving over the hot sand like snakes. So intently were the lads watching the motor boat that the first intimation of their peril they received was the harsh laugh of one of the Mexicans as the three closed up behind the unsuspecting youngsters. When Alex turned around he found himself looking into the steel-blue muzzle of an automatic.

“Welcome to our midst!” the boy said, trying to make a grin come easily.

One of the Mexicans seized Don by the shoulders and drew him back, as if about to strip the money belt off him, but another checked him with a coarse command. It was plain that they still believed the belt to hold the treasury notes, and plain, too, that the three were not trustful of each other. At least, for some reason, two of the three preferred leaving the money where it was for the time being.

The Mexicans were evidently waiting for some anticipated event to take place, for they sat down near the boys and kept close watch of the river and the shore opposite where the motor boat lay. The lads soon saw Case and Clay row down the river in search of Alex, saw King board the Rambler, saw the Mexicans desert him, and heard the shots fired across the levee.

They saw the dog spring overboard and swim down to them, but could not induce him to come to them. Captain Joe soon disappeared, and in a minute the Rambler dropped down to the point where he had left the water and Case landed on the island and made for the shore, almost exactly where the lads lay with their captors.

Alex tried to warn the boy, but dropped back in disgust when a gun was thrust into his face!

CHAPTER V.—A SURPRISE FOR THE GREASERS.

“Get up and get him!” commanded one of the three, in tolerable English, as Case reached the shore. “We’ll have to take him, too!”

One of the others replied angrily, but neither of them moved. It was evident that the three were suspicious of each other, and that neither of them cared to lose sight of the boy who was believed to have the stolen money.

They could not trust each other even to the extent of removing the money from the boy who was supposed to carry it. Each one thought the boy’s waist a more desirable place for the cash than the hands of either of his companions!

The Mexican who had spoken in English turned to Alex with a malicious grin on his dusky, dirty, greasy face.

“Call him here!” he commanded, pointing to Case, now turning off down the river and looking sharply about for the boys.

“I won’t!” replied the boy. “I’m not going to help you get him! I hope he’ll turn around and shoot you up! You let him alone!”

The other’s eyes blazed angrily and he leveled his revolver at Case, who was still increasing the distance between himself and the boys.

“Very well,” the Mexican said. “We can’t permit him to spy about the country. If you won’t call him to you, I’ll shoot him where he stands. I’ll give you while you count ten to decide.”

This put a different complexion on the situation. Alex hesitated only a second. He had every reason to believe that the Mexican would keep his word regarding the suggested murder of Case. He looked vicious enough to commit any crime, even that of shooting a boy in the back. If taken prisoner, Case might still stand a chance of getting away, while if deliberately shot down that would be the end of all things for him.

“Say, Case” the boy cried out, then. “Come on over here. I’ve got something to show you. Hurry up!”

Case turned about and ran toward the sheltered spot where the men lay with their prisoners. The boy’s face was wreathed with smiles, for he had been more than anxious about Alex. The Mexican’s evil eyes lighted up wickedly as the boy came up to his chums, looking suspiciously at the Mexicans as he advanced.

There were no weapons in sight, and so Case’s suspicions passed away in a measure, and he sat down by Alex’s side, his eyes fixed inquiringly on the others, and especially on Don Durand, the boy King had described as such a desperado. A bulging pocket at once caught the attention of the Mexican who had ordered Alex to call the lad into captivity.

“Stand up!” he ordered. “Stand up and throw out those guns!”

Case threw a hand behind his back, but before he could draw the other had him covered. Case stood up and dropped his automatics to the sand. Then he turned a scornful eye on Alex, who sat chuckling as if he considered it all a great joke.

“You’re a fine chum!” he said. “Turned pirate, have you?”

“Of course!” Alex returned. “I’ve got a choice collection of pirates here. Ever see any alleged human beings who would fit an electric chair any better than these three? They make a nice flock of jailbirds, don’t they?”

“Is that what you called me over here for?” asked Case. “To say that?”

“I called you over here,” was the reply, “to keep a procession of bullets out of your back. I’d rather have you here alive than out on the sands dead! This other chap is Don Durand,” he continued, making the introduction with a chuckle at the absurdity of the situation.

“I’ve heard of him,” Case answered. “King told me about the money he stole. King will soon be down after him!”

“So!” exclaimed the Mexican. “You think he’ll come after the boy? That is good news, but he needn’t to take the pains! As soon as we pluck the kid we’ll send him up to King. What, fellows?” he added, turning to his sullen companions with a provoking sneer on his hard face.

The two men nodded, but made no verbal reply to the question.

“Your friends seem to be afflicted with the mollygrubs!” Alex said, turning to the spokesman of the party. “Perhaps they’ve been eating something that doesn’t agree with them! Yes? No? What?”

“You seem to be a bright boy!” scowled the other.

“That’s the correct answer!” laughed Alex. “Why don’t you go on up to the motor boat and get King? He’s looking for you.”

“I’m not looking for him,” was the sullen reply. “I’m waiting for him to go away, then I’ll make myself scarce—him and his minions!”

Case now began to understand the situation. He had heard King say that Don Durand carried about with him the money he had stolen. He knew that King’s paid assistants had deserted him in order to get the money for themselves if they could. What he saw now, was that these Mexicans had originally been in the employ of the deputy, and that they had succeeded in getting the boy where King had failed. Still, he could not account for Alex’s being there with Don.

“King is going to remain here until he gets his prisoner,” he said, presently, glancing at Don. “He wants that reward,” he continued, “and is likely to get it, too, for all of you fellows!”

“He may have the reward,” snarled the Mexican, glancing at the boy angrily, as if ready to punish him for speaking without permission. “He may have the reward. All we want is the stolen money!”

“I hope it will burn up before you touch it!” Alex cut in.

“It is hot enough here to burn most anything!” Case observed.

“You see,” Alex commented, turning to Case, “what a fine, honest bunch I butted into when I followed Don off the rear deck of the boat! This lad, Don Durand, is a prince compared with the three Mexicans.”

The spokesman scowled fiercely, but the boy went on, taking a savage delight in making at least one of his captors show temper.

“These three,” Alex added, swinging a hand around the circle of dusky faces, “are the—the—well, they are the limit! They want to steal the cash from the boy who stole it from the man who stole it from another man! When they get it, if they ever do, they will fight over it—and this Englishman, or the person who speaks English, will murder his companions and take it all. It is a fine flock of jailbirds!”

The Mexican addressed a few angry words to a companion, and the latter arose and moved toward Alex with a long grass rope. The boy sprang away, but there was the ever-present revolver and the threatening face behind it, so he settled back on the hot sand.

“If you say anything more,” the Mexican snarled, “I’ll have your tongue tied instead of your hands and feet. Understand?”

Alex submitted to the tying without a word of protest, though he laughed bravely in the face of the man who did the work. The boy had accomplished his purpose, and was willing to suffer a temporary inconvenience. He had notified Case that the three captors were suspicious of each other, and probably would not stand together if a rush was made against them. He had also informed him that the money had not yet been secured by the Mexicans, and that they were as ready to fight King or their fellow countrymen for it as to battle with their captives.

Case understood that Alex was talking for his information, and once more turned his attention to the motor boat. He saw Captain Joe trot over the spit and the island and leap on board the craft, saw King and Clay conversing together for a time, and then saw the dog leave the boat with Clay close behind him.

The others saw what was going on, too, and the hearts of the boys sank at the thought of Clay becoming a prisoner. Before Clay gained the shore the Mexicans ordered the boys to their feet and retreated with them to a more sheltered spot higher up in the foothills. Alex did his best, during the move, to attract the attention of Clay and so warn him, but the boy was across the levee, following the dog closely, and so the prisoners with their escort passed over the level, scalding stretch of sand without being seen by the searcher, who was still on the opposite side of the barrier.

From their hiding-place the boys finally saw Clay climb over the sand levee and continue on his way to the hills. For a moment Captain Joe moved along ahead of him, his short ears pricked forward, his nose close to the ground, then the dog ran on and disappeared in a wrinkle to the south, where the hills reached out nearer to the shoreline.

The Mexicans were now holding what seemed to be a heated argument as to the advisability of shooting Clay before he got to them. The boys could understand only the words used by the spokesman, and he appeared to be arguing against such a step, advising that murdering an American was a crime which rarely escaped punishment. Clay heard the voices and stopped short.

“Alex! Case!” he cried out. “Where are you hiding?”

“Answer him! Answer him!” commanded the Mexican. “Tell him to come here! You will so save his life! Do it quick!”

“I won’t!” shouted Alex, raising his voice. “I won’t. Keep away, Clay!” he cried, lifting his bound wrists high above his head in order that Clay might see. “Keep away until you can bring help!”

“You fool!” shouted the Mexican. “You murdering fool!”

Instead of starting away, Clay ran forward, drawing his automatic as he advanced. Two of the captors fired at him but missed. At the same moment the third man, angry at Alex’s disobedience of orders, sprang upon him and raised a revolver as if to beat his brains out.

But before the weapon could fall something which looked like a white streak of wrath shot through the air and landed on top of the man who was bending over the boy. The Mexican struggled, clutched at the dog, and went down, with Captain Joe’s teeth in the back of his neck. Once on the ground, he lay perfectly still, as the dog’s teeth seemed less dangerous when no resistance was offered.

In the meantime, with Clay running forward, regardless of the shots that were being fired at him, and Don Durand making off toward the hills to the west, the two remaining captors lost interest in the situation and struck out on a swift run.

When Clay reached the spot where Alex lay, still bound, he heard the boy urging Case to follow on after Don and bring him back.

“He thinks Clay is an officer!” Alex shouted. “Go and tell him the truth. Shoot the Mexicans and bring him back!”

Case understood in an instant and started on a run after the three, by this time some little distance away. But the boy had advanced but a few paces when he saw one of the Mexicans reach out and drag Don to the ground. There he proceeded to search him for the money belt!

Case’s shot was not necessary at that time, for the other Mexican turned about and shot his companion through the head. Then he, in turn, bent over the boy, unfastening the belt with fingers which were uncertain because of the excitement of the time.

Case saw him lift the belt and turn away. He raised his revolver, which he had snatched from the ground at Clay’s first shot, and fired, not knowing whether he was aiming at the head or the heels of the fleeing man. The bullet struck the Mexican in the right shoulder and the belt dropped to the ground. Without stopping to pick it up the fellow continued his course to the hills, and, as Case did not follow, was soon lost to sight. Don Durand was also hidden in the hills.

When Case returned to Clay and Alex with the sand-stuffed belt in his hand they both reached out for it. Alex did not care to have the deception discovered, and Clay desired to take a look at the money which King had told him about. The Mexican looked on with sullen eyes.

Alex got the belt and then asked:

“Why didn’t you bring Don back with you?”

“He went up in the air,” was the reply, “just like Alex did earlier in the day. One second he was on the ground with a man searching him, and the next he was nowhere to be seen. Why did he run away?”

“He thinks Clay is after him,” grinned Alex.

“But he left his money behind,” Case put in.

“Yes,” Alex admitted, with an inward chuckle, “and I’ll look out for it until he returns. I promised him I would if anything happened to him. He’s keeping the money for the man it was stolen from.”

Alex placed the belt about his own waist and watched the Mexican wiggling away. There was no reason why he should detain him. Don was off into the mountains and there was little danger of his being caught. The money was hidden in the sand, and would be safe until either Don or himself dug it out. So, on the whole, it might be just as well to permit the fellow to make his escape!

The firing had, of course, attracted the attention of Deputy King, and the boys now saw him approaching. The Mexican saw him, too, and, bounding to his feet, darted away. In two minutes’ time he was out of sight in the hills. The third man lay dead where he had fallen.

When King came up there remained only Clay, Case, and Alex to greet him. Before he had quite reached them, the latter warned the others to say nothing of the money belt. After they were on their way, after Don was out of his reach, King would undoubtedly be told by some of the Mexicans that the belt had passed to Alex.

In that case, the boy reasoned, the pursuit of Don would cease for a time, and that would give him an opportunity to find the person the cash had been stolen from. Don had not told the whole story of the crime to Alex, but the latter had heard enough to cause him to sympathize with the boy and wish him all luck in getting away.

“Why,” King said, coming up to the little group, “I was sure I saw a smaller lad here with you. Where is he now? Did you let him get away?”

“He went right up into the blue sky!” insisted Alex.

“And the Mexicans went with him?” asked King, with a smile.

“They’ll not catch him,” Case answered, “if he keeps on running.”

“It looks more like they would catch the Rambler!” shouted Alex.

CHAPTER VI.—TEDDY BEAR MAKES A HIT.

All turned toward the river as Alex shouted out the warning. The level of the hiding-place chosen by the Mexicans was above that of the levee, and so the Rambler could be distinctly seen by the boys. She lay in the river without motion, save now and then a jerky pull at the anchor-chain, but just below her a rowboat was moving swiftly up stream.

The intention of the rowers, of whom there were three, to board the motor boat could not be denied. If they succeeded, and knew how to run the motors, the craft would be at their mercy.

Clay, Case and King started toward the river on a brisk run, but Alex loitered behind for a reason of his own. He knew that the three could do all that more could accomplish in the way of rescuing the boat, and he had a little mission of his own to carry out before leaving the place.

He wanted to secure the buried money and hide it safely away on the Rambler! Clay and Case believed that the belt had contained the cash when passed over to him. He wanted them to think, when the truth became known, that the sand filling had been supplied by Don without his knowledge, and with a view to deceive.

In short, he wanted no one to know that he had the money. He knew that he could trust Case and Clay, but he knew, also, that they could not be dragged into trouble because of the stolen money if they did not know that it was on board! He wanted to keep the cash for Don, but he did not want any one to know that he had it.

When, in the future, the belt should be brought out and shown to contain only sand, that would settle the money part of the affair so far as the boys were concerned, he thought. And King did not even know that he had the belt, and there was no need of his knowing.

Thus reasoning, even at that exciting time, Alex managed to fall down on the exact spot where the treasury notes had been buried and secure the oiled silk package without being observed in the act.

In fact, at that time, Clay, Case, and King were utilizing all their energy in the run they were making to head off the rowers and get to the motor boat first. The men in the boat were rowing to the utmost of their strength, and it seemed certain that they would win out in the race.

The three were still on shore when the rowers, abandoning their own boat in their haste, sprang on the Rambler’s deck. One of them rushed to get the motors into action, while the others drew guns and lined up along the side of the boat which the others would approach.

“There is no way but to fight it out!” Clay cried, drawing his own automatic. “If they get off with the Rambler now, that will be the last of her so far as we are concerned.”

The boarders crouched down behind the railing, exhibiting only ugly, triumphant faces. The man at the motors seemed to be having trouble with them, for there was no answering snap when he turned on the feed. The others finally gathered about him, as if to assist in getting the boat under way. Then an unexpected thing happened.

The boys saw the man who had first approached the motors spring into the air with a look of pain and terror on his face. Then the others almost turned handsprings getting to the prow of the boat. There was a sullen snarl on the deck, and then a furry object shot forward to the prow where the intruders stood.

In a moment the deck was clear, except that Teddy lifted his paws to the railing and looked across the island at the boys, winking one eye as if calling attention to a battle well won. He had been asleep by the motors and the intruder had stepped on him! That told the tale!

The bear had bitten the fellow through the ankle, and the battle was ended with that one bite! When the boys reached the boat the three men were swimming down stream in a futile effort to overtake their deserted rowboat. Teddy welcomed them on deck with a grin that was almost human.

After Captain Joe had been praised for his part of the fight on shore, and after Teddy had been told what a hero he was and given all the honey he could consume at one sitting, the two, the dog and the bear, repaired to the aft deck to compare notes and fall asleep.

“That’s some bear!” King said, as Teddy shambled away.

“The fellow must have stepped on him,” Alex grinned. “Teddy is particular about not being stepped on. He doesn’t like to be used as a rug. My, how those chaps did swim! Guess they thought there were a dozen bears in the water after them! Yes, Teddy’s some bear.”

King eyed Alex with disapproval for a moment and then asked:

“How did you come to let Don Durand get away from you?”

“Ask the Mexicans how they came to let us get away from them,” replied the lad. “I guess you saw what was going on. When Don ran away we were all pretty busy. Besides, you were not much farther away from him than we were. Why didn’t you catch him?”

“You were with him some time before the Mexicans came up?” asked King.

“Not so very long,” was the reply.

“What did he say to you?” was the next question.

“He said he took the money from a man who stole it, and would return it to its real owner as soon as he could find him.”

King broke into a laugh, his eyes narrowing as he looked at the boy’s face. Alex only grinned impudently back at him.

“You believe all he told you?” the deputy asked, in a moment.

“I didn’t say that. I didn’t say anything about what I believe. I can’t see as it makes any difference to you, anyway. I’m not a factor in the case. Don Durand is over there in the hills somewhere. Go and get him—if you can.”

King looked the boy straight in the eyes for a moment and then turned away with a laugh which the boys did not like the sound of, it was so low and threatening.

“All right!” he said. “I’ll go and get him!”

There was anger in the deputy’s face and manner as he stepped over to the sandy island and turned toward the shore.

“Wait!” Clay called after him. “Do you see what time it is? Most noon and we’re all hungry. Wait and have a dinner with us.”

“Anyhow,” Alex added, conciliatingly, “your Mexican deputies have taken to the mountains, and you can do nothing alone. Come on back and let us show you how hungry boys eat! No use to go ashore now!”

King, noting the changed tone, hesitated, looked shoreward for a time, and then turned back to the Rambler. He was silent for a time, and then asked:

“Did this Don Durand say where and when he expected to find the real owner of the stolen money? Did he say who owns it?”

Alex shook his head. His idea was that King should join them in a good, friendly dinner and then go away without asking questions about what Don had or had not said. He had a notion, a hope, too, that, in time, Don might join the Rambler crew if King would only get out of the way.

“We didn’t have time to talk about anything,” he explained, pleasantly. “Just as soon as we got to shore the ruction commenced, and we were kept busy taking care of ourselves. He would probably have come back to the boat with us if he hadn’t seen you. You frightened him away!”

Having thus adroitly placed the blame for Don’s flight on the deputy, Alex leaned back in his chair and pretended to be very sleepy.

“I don’t blame you for his flight,” King finally said, “but I really believe you might tell me more of his plans. It seems he became quite friendly with you. Has he kept all the money?”

“He said he had every cent of it,” Alex replied, not adding that at that minute the stolen treasury notes were hidden under his own clothing.

“If I could get hold of the stolen handbag and the money,” King went on, “I think I might be able to compromise for the boy. The man who lost the bag and the notes seems to want to get his property back more than he wants the boy punished.”

Alex considered this new proposition gravely. Could King suspect that he had the money? It seemed to the boy that the bag was of too trifling importance to be mentioned in connection with the money. That is, unless it had contained something of great value besides the treasury notes! Was King talking for his benefit in suggesting that the return of the money and the bag might release Don from further pursuit?

Then Alex remembered the papers he had seen Don stow away so carefully in the belt. They might be of the greatest importance, and he resolved to examine the belt at the first opportunity in order to see if they were still there. King watched the boy curiously, as if understanding what was passing in his mind.

“I don’t think he will ever give up the money,” Alex said, presently, “until he gives it to the person to whom he thinks it belongs. I guess he took it from this man Josiah Trumbull just to pass it on to the real owner. I don’t know anything about the bag. He did not even mention it to me,” he concluded, looking King enquiringly in the face.

“The man who came out from Chicago to see me,” the deputy explained, “laid great stress on the handbag. He seemed to think that Don would keep the bag as well as the money. And he wanted the bag just as much as he wanted the treasury notes.”

“How did he know that Don was out in this country?” asked Alex.

“Oh,” laughed King, “a lad like Don is easy to follow. He was in Phoenix and Yuma several days, but always got out just ahead of the man who engaged me to handle the case. He must have had warning of his coming, I think.”

“What was he doing in Yuma and Phoenix?” asked Alex, in a moment.

“Hanging around the hotels, evidently waiting for some one.”

“Huh!” the boy ventured. “I guess his story is true, then. He might have been looking for the real owner of the money and the handbag. Think so?”

“He may have been,” was the reluctant answer. “In fact, I believe the boy really thinks he is doing a noble deed in keeping the property he stole for some unknown person thought by him to own it.”

“Glad you think that!” exclaimed Alex. “Don thinks he is doing the right thing, anyway, whether he is or not. I like him!”

“At any rate,” King concluded, “he has a loyal friend in you, and I shall say no more about the matter while I am your guest. I hope, however, that he will give me a chance to confer with him before long.”

“If he should come to you to talk things over,” Alex asked, “wouldn’t you arrest him? Would you let him go back to his hiding-place unmolested? I may see him some day, and I’ll tell him what you say.”

“Yes; he may talk with me without fear of arrest,” was the reply. “And now,” the deputy went on, “that I have said just what I came back to say, I must be on my way. If you see Don, say to him that I want to have a talk with him, and that he will profit by the interview.”

King arose and, after expressing thanks for the boys' hospitality, passed over the sandy island and the tapering spit, and was soon lost to view in the foothills. Alex watched him with a smile on his shrewd face.

“There’s something about this case I haven’t got hold of yet,” he mused. “There was something in the handbag besides money. Anyway, the Trumbull person wants it, and Don hasn’t got it. Now, I wonder if the papers I saw Don have were in the handbag, and whether they are not the property the man who engaged King is so anxious to get?”

The boys were all tired, and it was finally agreed that they should run up the river a few miles, “just to get out of the bullet zone,” as Clay expressed it, and take an afternoon, siesta in the cabin, leaving Captain Joe and Teddy on guard. Alex was glad of this arrangement, as he was anxious to get a look at the belt, in order to see if the papers he had seen Don have were still there.

The motor boat was speeded for an hour or more, and then Case and Clay sought their bunks in the cabin. The little room was insufferably hot, but it was, at that, a slight improvement on the deck outside, so the lads made the best of it. Alex did not permit himself to sleep with the others, but lay awake, listening, with his eyes closed, until the regular breathing of his chums told him that they had passed into the land of dreams. The boy was miserably tired and sleepy, for the day had been a trying one, but he forced himself out of his bunk, and over the cabin roof to the aft deck.

Captain Joe was sound asleep on the prow, but Teddy crawled over the cabin with him and cuddled down by his side. Once out of sight of the others, Alex removed the belt and proceeded to empty the sand out of it. He remembered that Don had placed the papers he had been so careful of in the belt, and felt for them. They were packed into a close wad in one end of the opening, and he took them out.

They were covered with letters and figures which at first had no meaning to the boy. One held the letter “X” in the center, the same being surrounded by letters, standing singly and not in groups like words.

The other carried a sunburst in the center and was surrounded by figures, each standing alone, as was the case with the letters. For a time there seemed to the boy to be no connection whatever between the two papers, but finally he saw that one referred to location and one to time. The figures represented hour and minutes and the letters the points of the compass. Alex could make nothing more of them.

The papers must be important, for they had been as jealously guarded as the money itself. Alex thought that in time he might be able to read their message, so he made exact copies of them for daily use and put the originals back in the belt.

Then he unwrapped the money, saw that it was all there, and again placed it in the oiled silk. It was his idea to hide the money in one place and the belt in another. He tried to think of a safe place for each, but he was very tired and sleepy. That had been such a long swim! At last he rolled the notes up tight in the silk and placed the package in a pocket, resolved to hide it in the cabin when the boys awoke and left the way clear. Then he closed his eyes, “just for a minute,” he needed rest so much!

The motor boat drew sturdily at its cable. Captain Joe arose from the prow and cocked his ears at a mysterious sound. Teddy cuddled closer to the sleeping boy. The sun moved slowly to the west and the heat of the day in a measure departed.

Presently the dog moved over to the aft deck and stretched out with his nose on his paws. Alex, worn out with the activities of the day, slept on for an hour or more. When he awoke Captain Joe was pulling at his sleeve and Teddy, the mischievous bear cub, was romping about the small deck with one end of the oiled silk in his mouth—the strip of oiled silk which had held the fifty thousand dollars in gold notes!

CHAPTER VII.—THAT HAUNTED STERN DECK!

Alex’s first thought was of the money, the fifty thousand dollars in gold notes which he had been handling just before he had dropped off into the sound sleep from which Captain Joe had awakened him. The oiled silk the bear cub was playing with had enclosed the money! That had not disappeared, but where were the precious notes—the money upon which so much depended? The boy was dazed for an instant.

Then the thought that one of his chums might be playing a practical joke on him came to his mind. Of course that was it! The motor boat was anchored nearly in the middle of the Colorado river, not far from the Gulf of California, at least a mile from either shore, so no one could have stolen the money!

The position of the sun told the boy that he had not been asleep more than an hour, and there were no signs of a boat on the river. If some thief had boarded the boat Captain Joe would have attacked him. Then he remembered that the dog had not attacked Don, and was not so certain of that point. Still, he was hopeful that Case or Clay had taken the money while he slept, in return for his secrecy in hiding the fact of its possession from them. Yes; that certainly was it.

The thought cheered him, and, rising to his feet, he looked through the open window which gave on the interior of the cabin, expecting to see the boys chuckling over his distress. But the boys were still asleep.

This was a facer! The next impression that came to the boy was that Teddy had shaken the notes out of the silk covering and that they had fallen into the river. This was not a pleasant conclusion, and Alex tried to dodge it, but still it forced itself upon him.

And the original papers? They had gone with the money! Alex felt like dropping into the river and sinking to the bottom. He had copies of the papers, but he just could not lose that money! It did not belong to him! It did not belong to the boy who had entrusted it to him. He would be accused of stealing it!

He looked in every crevice of the aft deck, even lifting the trap covering and looking down on the gasoline tanks. He crawled quietly back over the cabin roof and searched every part of the deck. There was no trace of the money or the papers. It was maddening!

“I guess the notes are drifting down stream,” the boy finally said, with tears of vexation in his eyes. “Captain Joe,” he added, turning to the dog, who had followed him over the cabin to the forward deck, “why didn’t you wake me before? Why did you let Teddy get the package?”

Captain Joe looked gravely up at the boy and wagged his stump of a tail. His eyes said that he knew all about it, and could explain everything if he only had the gift of speech!

“Did some one come aboard and get it, Captain Joe?” the lad asked, half convinced, in his misery, that the dog could explain the mystery.

The dog seemed to understand the question, for he sniffed at the rail of the boat, appeared to pick up a scent, sprang over the cabin, and sat down on the aft deck to look steadily into the river.

“Oh, he did!” Alex cried. “He came in over the prow, climbed over the cabin, dropped down on the aft deck, snatched the money, and dove into the river. I understand, old boy! But why didn’t you stop him?”

Captain Joe, recognizing the tone of reproach, slunk back over the cabin and lay down on the prow, a favorite resting-place. Teddy laid the strip of oiled silk at Alex’s feet and looked up with twinkling eyes, as if inviting the boy to pick it up and have a romp with him!

“You poor little beastie!” Alex exclaimed. “If you could only talk for a minute I’d soon know where the money went to! I believe Captain Joe might tell me more if he wasn’t so lazy!” he added, going back over the cabin and calling the dog to him. “I believe that stern deck is haunted!” he added.

This time he gave the silk to the dog and waited to see what he would do with it. Captain Joe was undecided for a moment. He seemed to think Alex a very foolish boy for handing him such a rag as that to pick up a scent from! Then he went to the aft deck and laid the silk down on the extreme edge of the low railing. Teddy snatched it off and began romping with it, much to the disgust of the anxious boy. Hopeless!

“Fine old watchdog you are!” Alex exclaimed. “Next thing you know, some one will come on board and steal your ears! You let Don on this deck, and permitted him to sleep here, you ornery cur, and never said a word to us about it! Now you’ve let some pirate come here and steal more money than I’ll ever be able to pay back—not if I live to be a thousand years old! I didn’t think it of you, Captain Joe!”

The dog slunk away, and Alex sat down to the bitterest time of his life. What could he say to Don when he returned and asked for the money? What could Don say when questioned regarding the honesty of his motives in taking the handbag and the notes from Trumbull? He could not restore the money, and therefore his assertion that he had taken it only to place it where it belonged would look decidedly flat.

Alex was too honest to think of denying that he had taken the money from its hiding-place in the sand, although no one knew that he had done so! He could only admit taking it and tell the story of its loss—a story which he feared no one would believe! The fifty thousand dollars were gone, and the boy believed that his chance for an honorable career had gone with them.

At last he picked up the silk from the ledge where Captain Joe had placed it, folded it carefully, and put it into his pocket. Then he looked about for the belt. That, too, was gone! He looked everywhere for it, but it was not found.

He made an especially careful search for it because he knew that he must account to Clay and Case for it. They knew that he had had it. They had been led to believe that it still held the stolen money! What would they say when he told them the exact truth about the matter?

The boys slept until nearly sunset, and then came rolling out of the cabin proclaiming appetites beyond those of all other days! As for Alex, it did not seem to him that he would ever want to eat again!

“Tell you what, boys,” Clay explained, as the three sat down to a quickly-prepared supper, “we ought to go on up the river to-night. We ought to get farther away from the Mexicans and the deputy sheriff. They are hot after the money Alex is carrying around in that belt, and we may be attacked at any time. We ought to get up past Yuma, at least!”

Alex bit his lip and turned his head away. The time had come when he must face his chums with a story so flimsy that he would not have believed it if coming from the lips of another! The time had come!

“Yes,” Case agreed, “we ought to be getting away from here. The men we did business with down the river would go to any trouble to follow us; would commit any crime to secure possession of the fifty thousand dollars Alex has in the belt the Mexican robbed Don Durand of.”

“Where is the belt?” Clay asked. “Why don’t you show up, Alex, and let us see what a stack of money looks like? How long do you suppose we will have to keep it before Don gets to us and claims it?”

“Yes; produce it!” cried Case. “I can smell it now!”

“I haven’t got it!” was all Alex could find words to say just then.

The others looked at him in utter bewilderment until his eyes fell.

“Who has it, then?” Clay demanded, in a moment.

“I don’t know!” Alex replied, drearily, and then he told the whole miserable story—of the sand in the belt, of the papers hidden with the sand, of the concealment in the levee, of the removal, and finally of the loss.

Clay drew a long breath when the boy had concluded.

“I don’t expect you to believe it,” Alex ventured. “I wouldn’t believe a yarn like that if told me by a preacher.”

“If I told you, you would believe it, wouldn’t you?” asked Clay.

“Yes,” answered Alex, “I would!”

“Then I believe you!” Clay shouted, loyally, taking the boy’s hand.

“And I, too, believe you!” Case cut in. “It is queer, though!”

Alex tried hard to tell the boys how much he appreciated their loyalty, but his lips were quivering, his throat was too dry for speech, and there was a suspicious moisture in his eyes, so he gave over the attempt and sat looking at them in a way which told the story much better than any words could have done. Half his burden had dropped away, for they trusted him. Clay was first to speak.

“Suppose we spot the thief by the process of elimination,” he said.

“Go ahead, I’m all clogged up, mentally,” Case answered. “How any one ever got on the Rambler and got off again without our knowing it, is something I can’t understand. Why, there’s not been a boat in sight all day, unless one came up while we were asleep,” he added, a little sheepishly. “I believe there’s magic in it.”

“Who knew that you had the money, Alex?” asked Clay.

“The Mexicans, and they thought it was in the belt. Don probably thinks it is still in the sand heap, and King never knew I had it.”

“Then we have only three to look after. These are the two Mexicans and Don. The others are out of it,” said Clay.

“But why Don?” asked Case.

“The three I have named would have plenty of reasons for following the boat,” Clay continued. “Now, let us consider their several chances of overtaking us. We have traveled about fifteen miles by river, but we have passed around a long point of land, and are not more than eight miles from the starting point. You can see how it is by looking at the river map.

“Now, the Mexicans would be likely to have horses near at hand, as they had been deputized as special officers to assist in the capture of the boy. They could, by quick action, chase across the point and head us off.

“Now, about Don. He would go back to the levee to look for the package of money and would lose time. Besides, he would have to travel on foot, so that, it seems to me, leaves him out of it. This passes it all up to the two Mexicans. What do you think of my Sherlocking, eh?”

“Unless Teddy shook it out of the package and dropped it overboard, you must be right,” Alex hastened to say. “He was playing with the silk, you remember!”

“Or unless Don ran across the point of land we sailed around and took it,” Case suggested, with a wink. “He might have done so, you know, so that knocks your Sherlocking all out!”

“What would Captain Joe be doing while the Mexicans were on the boat?” asked Clay, perplexed. “I never thought of that! He loves Mexicans like cats love hot soap. Guess my elimination theory has led me into a hole that gets me nowhere! Now, what is to be done?”

“I don’t know!” Alex answered. “I’ve lost the power of thought.”

“I can’t think in such large sums as fifty thousand dollars,” grinned Case. “Don’t ask me for an expert opinion! I can’t give one!”

There was a long silence, and then Alex took out the copies of the inscriptions—as he called them—which he had found in the belt. Clay and Case opened their eyes wide at sight of them. When Alex explained their history, as far as he knew, the boys fell to studying the letters and figures with anxious interest. Alex looked on doubtfully.

“What do you make of them?” he finally asked, as Clay held one of the papers up to the light.

“Is this an exact copy?” he asked. “Did you place your letters and figures just as the letters and figures on the originals were placed?”

“I surely did,” was the reply. “They are exact copies.”

“Hush, then!” Clay whispered, with a grin. “We tread on dangerous ground! Aha! These papers tell of the whereabouts of a buried treasure!”

“Hush!” repeated Case, with a mocking face. “Hush! Also S’cat!”

Alex looked at his chums reprovingly. This did not seem to him to be a time for by-play. He had lost a large sum of money which did not belong to him, and all the world looked black and creepy!

“Oh, cheer up!” Clay laughed, slapping the boy on the back. “We’ll find your money for you! Everything always comes out right with us! You know that yourself. Everything always comes out just as it should!”

“You know it!” Case cut in. “You know that we always find the right answer! Now, suppose we let this money and these inscriptions take care of themselves for the present, while we decide what to do to-night. It will be bright, from all appearances, so perhaps we’d better be on our way to the big noises of the Colorado.”

“I’m willing to go anywhere!” Alex complained. “I can never look myself in the face again! Think of losing fifty thousand dollars, when a five case note would look like unlimited wealth to me!”

“Here comes a fleet of river boats!” Clay shouted. “Look at the little, one-sided things! What they loaded with. Case?”

“I’m not a mind reader!” laughed the boy. “Looks, though, like they were loaded with merchandise. I suppose they’ve been lying in some cool cove all day, and will make good time to-night.”

The little steamers came slowly up to where the Rambler was anchored and passed on without giving the motor boat more attention than a close scrutiny from the decks. The sun was going down over the ranges to the west and dusk was settling over the valley of the Colorado.

The boys heard the rattle of spars and chains for some time after the little steamers had disappeared under the veil of the twilight, and now and then a black column of smoke from some stack proclaimed the activity of a fireman working down in a shallow hold.

After a short wait the Rambler was gotten under way, and the boys prepared for a wakeful night. They sat on the forward deck for a long time, talking over the strange events of the day, and then Alex was almost forced by his chums off to his bunk.

As the weary, discouraged lad turned into his bunk he heard noises on deck which set him to wondering what his chums were doing, but he was too sleepy to open his eyes. He turned his face to the wall and was soon asleep. Case and Clay sat well forward and did not hear the bump of a boat against the stern.

The dark figure on the aft deck was out of their sight.

CHAPTER VIII.—DEPUTY KING GETS A BATH.

Alex was awakened by the little cabin clock striking midnight. He lay quiet for a moment without opening his eyes, for he was still very tired and sleepy, notwithstanding his unfortunate afternoon siesta. Presently he felt the cold nose of the bear brushing against the palm of one hand, which was hanging over the edge of the bunk.

As this was a trick often resorted to by the cub to attract attention when he was hungry, or wanted some one to play with, the boy took no special notice of it. Then a strange rustle and stir in the cabin came to his ears, a combination of sounds which proclaimed a hustling about of furniture and a tossing about of small articles.

At that he opened his eyes and sat up. Then he rubbed his sleepy eyes and stretched out a hand in the direction of the place where he always kept his automatic at night. The weapon was not there!

What he saw was King, the deputy sheriff, opening and closing the drawers under the bunks where Clay and Case slept. He was tumbling the contents of the drawers over the floor and frowning savagely as he turned the medley of furnishing goods with nervous hands.

Now, how came it that King was on board the Rambler? The deputy had left the boat for the purpose of pursuing the boy who had taken the money and the handbag from Josiah Trumbull. By this time he ought to be far into the mountainous district to the west. And what was he doing there? And where were Case and Clay, and Captain Joe?

These questions, and many others of a similar kind, came to the boy as he watched King throwing the boys’ shirts, collars, ties, underclothing, and toilet articles about. But no answers came, except that a low growl from the dog sounded from the open doorway. Turning, Alex saw that he was tied by a chain to the top bar of the deck railing.

Captain Joe was pulling at the chain, his red eyes were glaring angrily, and his capable teeth showed under his snarling lips.

Alex beckoned silently to the dog, and he pulled at his chain fiercely and set up a great barking. Then King looked at the dog and at the bunk where the astonished Alex sat, still motioning to the dog.

“Good morning!” the deputy said, with a smile which was not altogether hostile. “How do you find yourself this morning?”

“You’ve got your nerve!” Alex replied angrily.

“If I should lose my nerve,” the deputy returned, with a wink at the struggling dog, “I wouldn’t get any jobs! Nerve is an asset with me.”

“What are you doing here—nosing in those drawers?” asked the boy.

“Looking for the belt you picked up down below,” was the reply.

“I didn’t pick it up,” Alex answered, with a frown which did not at all improve his appearance. “I didn’t pick it up.”

“Your friend did, though, and gave it to you. Where is it?”

“I haven’t got it! Some one came on board and stole it.”

“That may be. Clay and Case said the same thing. Let the belt go. Where is the money?”

“Stolen,” answered Alex. “Carried off when the belt was taken.”

“See here,” King went on. “Your chums told me about that, and I do not believe it. No boy would go to sleep sitting up, with fifty thousand dollars in treasury notes in his lap. That’s too thin.”

“All right! You don’t have to believe it.”

“Besides, who is there that knows you have the money, except me and the two Mexicans? Don Durand ran away without waiting to see what became of the belt, so he doesn’t know, and the Mexicans, who do know, and who told me, have been in my company nearly ever since, so they didn’t get it. You may as well tell me the truth. It will save time.”

“I have told you the truth, but you may keep on mussing up things if you want to. You’ll get your pay for it some day!”

“No threats, please! I rather like you boys, and I’m sorry you got mixed up in this affair. I’ll do the best I can for you, but I must have that money! Also, I must have that belt. There are papers in it which I need in my business. Get up and get the money and belt!”

“If I could,” Alex replied, “I’d throw them overboard before I’d let you have even one look at them! Where are Clay and Case?” he added.

“I’m sorry for that, too,” King replied, “but I had to drop them off on a little sand heap not far away. They cut such annoying pranks that I had to do it. I have the boat anchored, you see, and you may run back and get them as soon as I get the money and the papers.”

“What papers?” asked Alex, innocently, as if he had never heard of the queer documents before. “What you talking about?”

“The papers that were in the handbag,” King replied, patiently.

“They were in the belt when it was stolen,” Alex answered, telling the exact truth, but saying nothing of the copies he had made, and which were at that moment in an inside pocket of his coat, hanging on the wall not far from his bunk.

“Oh, very well!” the deputy said, turning to his work again. “You lie right there while I search the boat from stem to stern. It may take a couple of days, but I’ll do it right while I am at it.”

Alex watched the deputy turning out drawers and poking under them, investigating the motor pit, and even moving the provision supply out of the storage compartments. Anxious as the boy was, it still amused him, for he knew what a hopeless search it was.

King seemed to think that Alex, deprived of his revolver, would not attempt interference with his search. He looked over at him now and then and occasionally spoke to Captain Joe, but for the most part he kept on with his work of searching the boat. This went on for two hours or more, until, in fact, a pearl flush crept into the sky.

During all this time the boy had been thinking fast. How was he to get rid of King? For all he knew, defeated in his search, as he was sure to be, the officer would run the boat up to Yuma and lock him up on charge of receiving and concealing stolen property. And, then, Clay and Case must be having rather a hard and anxious time of it down on the sand island where they had been landed, at the point of a gun, by the deputy.

Captain Joe seemed to have exhausted his rage, and was now showing his teeth only when King came near him. The dog seemed to think that if Alex could lie easily in his bunk and talk with the man who was searching the boat he had no cause to interfere! Besides, he was tied so securely that there was no hope at all of his getting free!

Whenever the boy moved uneasily on his bunk King gave an uneasy glance in that direction. Once Alex tried to get to a revolver which he knew to be in a cupboard near the rear of the cabin, but King ordered him to lie down again before his feet were off the bunk.

After a time, when there was more of pink than pearl in the eastern sky, Teddy climbed up to the bunk and lay down by the side of the boy. He was preparing to go to sleep when Alex began whispering in his ear:

“Take him, Teddy! Take him! Give him a bath!”

Ever since Teddy’s capture on the Columbia river trip the boys had made a playmate of him. He had been taught to play leap-frog, and to wrestle and box. While bathing from the boat the boys had taught him to follow them into the water, and even to trip and bunt those on deck into the river if they did not jump in quick enough to suit him.

Alex was now trying to revive the play spirit in the bear in the hope that he would attack King and try to push him into the river. Not understanding the game, the deputy would be apt to take alarm at such a rush as Teddy sometimes made and so give the boy a chance to arm himself.

The cub sat up on the bunk as Alex talked to him, but did not seem to understand what was wanted. He put his paws in boxing position as he had been taught to do, and invited Alex out on the floor to have a bout with him! But this did not help at all!

“Tip him over, Teddy! Tip him into the river!” Alex whispered.

Teddy paid no attention to the order, but continued to invite a boxing contest, much to the disappointment of the boy. While this was going on a long call from down the stream reached Alex’s ears. That was Clay or Case. They were getting tired of their enforced residence on the island and were asking how much longer it was to continue.

Teddy ruffled his ears at the sound of the familiar voices and King stood up to shout an answer back. It was a taunting answer, too, and the boy in the bunk came very near springing out and taking his chances in a hand-to-hand combat with an armed man!

The prow of the boat was up stream, as the anchor cable led from that part of the craft, so the aft deck was nearer to the island where the boys had been landed than the bow. Besides, the bulk of the cabin was between the deputy and the island. Desiring to urge upon Clay and Case the necessity of delivering the money and papers to him, King stepped up on the cabin roof and entered into conversation with them.

An hour before the deputy would not have done this, but now he was becoming a trifle disheartened. He had gone over the boat pretty well and had found no trace of what he sought. The stories told by the three boys agreed, and he began to wonder if they were not the truth. He was inclined to be friendly and, once convinced that the boys were not deceiving him, he would have treated them with every courtesy.

At last Teddy appeared to understand that it was to be a game of hide-and-seek in the water, and bounded off the bunk. King was standing on top of the cabin, making a trumpet of his hands, talking to the lads he had marooned down the river. That was an old pose. The boys had often stood erect on the roof and derided each other’s swimming efforts.

When the bear came out on the deck King looked down and yelled savagely at him. This was still a part of the game, too, for the lads often taunted the cub and then sprang away from him and plunged into the river! So, when the deputy called down at the bear, the bear sprang at the deputy, caught his sharp teeth into one trousers leg and promptly and deftly pushed and pulled him off the roof and into the river, where he rolled him under a couple of times and swam away, around to the other side of the boat.

Alex was out of his bunk the instant he heard the splash. King was spluttering out great threats when the boy ran on deck with the revolver he had taken from the cupboard.

“Taking an early bath?” shouted Alex derisively, as he showed his weapon. “Don’t come too close to the Rambler! You can’t come aboard.”

King came to the surface again and, ejecting muddy water from his mouth, shouted back.

“If you’ll assure me that the money is not there—”

Teddy swung around from the other side of the boat and ducked him.

Alex went to the motors and set them in motion. Then he called to the cub. Teddy was having the time of his life playing with the angry and half-drowned deputy, and did not respond.

Alex put the boat in motion and called back to the cub:

“Go it, old top! If you want to drown, stick out there!”

The boys had acquired such a habit of talking to the bear as if he were a human being that Teddy actually understood a good many things that were said to him. Still, it was not the words but the departure of the boat which now brought him away from the officer.

King followed the cub as he swam toward the boat. The boy motioned him to remain away, and added that if he wanted to save his strength he might as well head for the nearest shore, which was something like half a mile away at that point.

“But I can’t swim that far!” came back from the water.

Alex threw out a life preserver and shouted back:

“Float down, then, and kick in as you go along!”

King seized the life preserver and headed for the shore, while the boy devoted his energies to getting Teddy on board and running the boat at full speed down the river without hitting any of the shoal places shown by the ripples to be dangerous. In a very short time he came to the sand island where Clay and Case were.

He threw down the anchor, just below, and stood on the prow making faces at his chums until they threatened to maroon him the first chance they got! Captain Joe was now making a great clamor with his chain and Alex released him. The dog was instantly in the water, swimming to the boys, now wading out toward the Rambler.

“You’ll have to swim!” Alex shouted, in a moment. “I can’t come any closer to you, and we’ve lost the rowboat, as you know!”

“We can’t get any wetter than we did swimming over to the island,” Clay grumbled. “Where is that deputy from Phoenix?”

“Making for the shore!” laughed Alex. “Teddy Bear dumped him into the river and I sent him off with a life preserver.”

“I’d like to have sent him off with a sore head!” Case muttered, as he climbed up on the deck, his teeth chattering. “He sneaked on board from a passing boat and got the drop on us or we wouldn’t be here!”

“He thought he was in the line of duty,” Clay put in, “but it was rather tough on us. We never saw him until he had us covered!” Did he find anything he wanted on board?”

“Not a thing!” Alex replied. “All he got was a bath!”

“I’m going to buy a ton of honey and present it to Teddy, with a set of appreciative resolutions!” Clay declared, as he followed Case to the deck. “There never was a bear that had such sense!”

The sun came out hot and red, and the boys kept under the shelter of the cabin as much as possible that day, still they kept the motor boat running at good speed. They talked over the loss of the money many times but were unable to reach any logical solution of the puzzle.

That night they anchored within sight of Yuma, Arizona. Clay declared that Alex was too much of a sleepy head to be trusted to keep watch, and so resolved to stand guard until midnight and then awake Case.

But Case was not called, and at daylight Clay was nowhere to be found!

CHAPTER IX.—ANOTHER GUEST FROM THE RIVER.

Clay, after Alex and Case were asleep in their bunks, sat out on the forward deck playing with Teddy and informing him what his opinion of him was! The cub appeared to understand the compliments paid him, but Captain Joe looked like he was being overlooked in the allotment of honors for the events of the day. Clay only scolded him for not uttering a warning when King came on board.

The lights of Yuma shone in the distance, and now and then the rush and roll of a Southern Pacific train stirred the air, but for the most part it was very still, except for the murmur of the river, where the Rambler lay.

The happenings of the day had been so remarkable that Clay’s head almost ached as he tried to place them in orderly array for deliberate consideration. The larceny of the money troubled him most, and a good deal of his thought was given to the mystery of the taking.

He had taken a fancy to Don Durand, and did not like the idea that further trouble might come to the lad through a member of the Rambler company. Don would certainly appear, in time, and claim the money. What was there to say to him? Would he believe the naked truth when it was told? Clay was sorry to conclude that he would not!

While the boy worried over the situation, a light showed on the the city side of the river, such a light as might have been made by the flare of a match. Clay watched the point from which it had shown with lazy interest. The person who had struck the match was probably some tramp, he concluded, some vagrant loitering there in the hope of finding a lodging for the night on board the boat.

Directly another match was struck. This time it was swung in a circle until the flame was extinguished by the light breeze which was blowing from the west. Clay began to take a greater interest in the matter, for it seemed that the person on shore, whoever it was, was attempting to attract his attention.

There was no moon, but the stars were out, and the boy knew that the bulk of the Rambler could be quite distinctly seen from the shore. The display of light, he thought, might be either a salute to those on board or a signal to some one on the bank. Curious as to what it really did mean, he resolved to sit still and await developments.

It had been an exciting day, and the previous one had been more exciting still. The most unexpected events had happened since the Rambler had come within sight of the Colorado river. The boy was weary of the complications which had been forced upon his companions and himself, and anxious to be away on stretches of river where there would be only the great facts of Nature to deal with, still his natural curiosity held his attention to the vagrant light on shore.

Half a dozen flares were shown, and Clay began to consider the advisability of responding to them. He put the notion aside for a time, and then, the signals continuing, he got out his searchlight and sent a circle of light toward the shore. Then a boyish voice called out:

“Hello, the boat!”

“That’s not a sailor,” thought Clay, showing his light again. “A sailor would have shouted ‘Ship ahoy!’ Now, I wonder what the fellow wants, at this time of the night?”

Again the voice came out of the darkness:

“I want to come aboard. Can you send a boat after me?”

“We are not at home to-night,” laughed the boy, amused at the impudence of the fellow. “Besides,” he continued, “we have no boat. If you want to see me, you must swim the river.”

This dubious invitation was accepted almost before the words were out of the lad’s mouth, and Clay heard a quick splash in the water. Directly heavy and labored breathing told him that the visitor was nearing the boat, and that he was having a tiresome time on his journey.

Presently the light of the stars showed a head bobbing on the surface of the water, not three yards away, and Clay turned his light in that direction. It revealed only a head of tow-colored hair and a pale, distressed face, with eyes strained and anxious from over-exertion. Then a pair of thin, boyish shoulders lifted above the water.

“It is only some kid seeking adventure,” thought Clay, tossing down a rope. “I’ll take him on board long enough to give him a rest, then he can swim back to the shore. Here, kid!” he went on, “take hold of the rope’s end and I’ll draw you out of the moisture!”

With the assistance of the rope and the strong arms at the boat end of it, the visitor was soon on deck, sitting flat and leaning against the railing, as if every ounce of strength had been used in the swim from the shore. Clay’s light showed the stranger to be a boy of not more than fourteen years—a ragged, hungry-looking boy!

“Gee!” the boy panted, after a time, “I reckon I’m all in!”

“What did you do it for?” asked Clay, wondering if the boy really was as hungry as he looked and wondering, too, if he could feed him without waking the sleepers in the cabin.

The boy did not answer the question, but sat looking over the boat, as if trying to search out some familiar feature or face.

“You might be a fish,” Clay said, “the way you come up out of the river at the end of a rope. What do you want?”

The visitor leaned weakly back against the railing and shut his eyes as if too tired to keep them open. Clay watched him curiously for a moment and started for the provision box at the back of the cabin.

“I know what you want, first of all,” he declared, turning and speaking in a low tone. “You want a square meal? What?”

“That’s the answer!” said the other, opening his eyes. “That’s it.”

“Why didn’t you say so, then?” grumbled Clay, hustling to the provision box and bringing out cold baked beans, bread, fried fish, and a huge piece of pie. “Get busy, now!”

The boy needed no second bidding. He stowed away the victuals in a way highly satisfactory to his host, and looked up with a grin on his thin face.

Clay removed the dishes and sat down by his side, but just then Teddy came nosing out of the cabin and invited the boy to box with him. In a second the kid was on the railing and half over into the water. Clay’s voice was shaking with laughter as he reproved the cub and pulled the boy back on the deck. Teddy walked away on his hind feet in offended dignity.

“You shouldn’t mind a little thing like that!” Clay laughed. “You’d get used to seeing things if you sailed on the Rambler long!”

“Then this is really the Rambler?” asked the other.

“Sure it is! Where did you ever hear of the Rambler? What’s your name? How long have you been growing that appetite you just had on exhibition? It was a corker, if anybody should ask you!”

“My name is Tom, and I’m from Chicago, and I’ve been without food for fourteen weeks, if you want the truth!”

“Hunger doesn’t seem to affect your imagination!” Clay suggested.

“Well, I don’t know how long it has been since I had a square meal like that! I invaded a free lunch counter yesterday morning, but the brute of a barkeep tumbled me out into the street.”

“Did you walk from Chicago?” asked Clay, after a moment’s silence.

“I rode the rods,” was the reply. “I’m all stuffed with sand. I’ll turn into stone, like Arizona wood, in about three weeks.”

Clay regarded the boy curiously. He spoke gravely, saying odd things as one might repeat a lesson at school.

“Tom?” he said, then. “What else besides Tom?”

“Durand—Thomas Jefferson Durand! My parents gave me a long name because it didn’t cost them anything, and they had nothing else to give me. I’ll bet the first Thomas Jefferson wouldn’t look so dignified in his pictures after he had rode the rods from Chicago! Would he, now?”

Clay did not reply, for he was wondering if this Durand and the Durand he had been thinking about that night were brothers. It would be a strange coincidence if they were! This Durand seemed to know about the Rambler! Perhaps, in some mysterious manner Don had warned him to wait for the boat as it passed up the river and ascertain if the fifty thousand dollars had been safely taken out of the sand levee!

This was a disquieting thought, for the money was gone! Clay decided to learn the truth immediately, so he asked:

“Where is your brother Don? Have you seen him lately?”

Tom winked his eyes and pulled at his tangle of tow-colored hair.

“Do you know Don?” he asked. “When did you see him last?”

“So he is really your brother?” demanded Clay, feeling that the hour of settlement for poor Alex was indeed close at hand.

“Sure he is!” was the reply. “He’s out in the desert somewhere. He snatched a lot of money in Chicago and got away with it. So he isn’t in any of the society columns just now. He’s supposed to be in retreat!”

This looked a little better, but Clay kept on with his questions.

“Where did you learn about the Rambler?” he asked. “How long have you been waiting here for us? Who told you to wait?”

“Don did,” was the quiet reply. “He said he’d wait farther down the river. We’re going up the Colorado with you—so Don says!”

“So Don was here recently?”

“Indeed he was, and told me to wait. He came over from Phoenix on a run, with a thousand deputy sheriffs after him. He got a boat and went down the river to meet you. Did he find you?”

Clay did not answer the question. Instead he asked one.

“So you both thought the Rambler would be a good place to hide?”

“Of course we did—to hide in and also to travel on! We know all about the Rambler. The Chicago newspapers wrote you up, you and the boat. We read all about the Columbia river trip, and all about the trip you were ready to take on the Colorado, so, as we wanted to get up into the canyons, we decided to go with you.”

“What are you going to the canyons for?” asked Clay, thinking of the mysterious papers Alex had discovered in Don’s belt. “Are you both going there to hide until the trouble blows over?”

“When we come back from the canyons,” Tom declared, with a weak grin, “J. P. Morgan won’t have a thing on us! You see!”

“Money up there?” asked Clay, shortly, resolved to draw the boy out.

“I’m not going to tell you what there is in the canyons,” was the reply. “Say,” Tom went on, “what do you know about fifty thousand dollars in treasury notes? Ever hear of such a wad as that?”

Clay imagined the truth would have to be told then, but he thought best to put off the evil hour as long as possible, so he said:

“We saw Don down the river, but a deputy chased him away into the mountains. Probably he’ll manage to find us again before long.”

“He was hungry, wasn’t he?” asked Tom, with a wink. “He gets awful hungry sometimes! He’s been out in the desert a long time.”

“Yes, he was some hungry,” Clay replied, with a laugh. “We fed him up on pancakes and honey, and he seemed to like them.”

“You bet he did. He’ll find you again if you remain here a day or two. He’s going up the Colorado river with you. What’s your name? Is it Case, or Clay, or Alex? You see, I know your names!”

“I see you do! Well, I’m Clay, and Case and Alex are asleep.”

“Asleep with the bear and the dog? Well, that’s fine. Only I was scared when the bear came at me. Now, let me tell you, Mr. Clay. If you stay here until to-morrow night Don will find you, and we’ll all go up the river together. He’ll soon be along on some up-river boat.”

Clay was of the opinion, just then, that he would rather not wait for Don! If the meeting could be delayed, he thought, some way of finding the money might be discovered. At least he hoped so with all his heart.

While the boys sat there a river boat came toiling up stream. She puffed past the place where the Rambler lay, dark, and drew up at a little pier some distance up the river. Tom pointed to a number of passengers, outlined against the pier lamps, who were leaving the boat for the shore, and suggested that his brother might be one of the number.

Clay hoped that he was not, and did not consider it probable that he was, for it did not seem likely to him that the boy would venture out into the open with King so eager on his track. Presently the clamor at the pier died out and the night was still again. Tom huddled closer to Clay and pressed a folded paper into his hand.

“Have you ever seen anything like that?” he asked, shivering.

Clay sheltered his electric and opened the paper. Then he was silent for some moments. He wanted to think out this new complication.

The paper showed two rude drawings, duplicates of those which he had seen on the papers taken from the belt! There were the “X” and the sunburst, surrounded by letters and figures! The boy was puzzled.

“What do these drawings mean?” he asked. “Where did they come from?”

“Don got them out of Trumbull’s handbag,” was the evasive reply. “He stole them! That is, he stole the originals. It was the papers he sought when he stole the handbag. He did not know that the fifty thousand dollars were in the bag when he took it, but he kept the money, just the same, and will restore it to its rightful owner as soon as he finds him.”

This was another phase of the matter! The larceny of the money was only incidental! The mysterious drawings were the important things. Then Tom went on to state that the series of drawings was not complete, that there was one missing, without which the others were worthless, and that one could be found in an old house at Yuma, which accounted for the boys making that city their objective point in leaving Chicago! Clay thought he saw a chance to recompense Don, in a measure, for the loss of the money.

“Do you know where this old house is?” he asked, in a moment.

Tom said that he did, and for a long time the boys discussed the advisability of making the search for the third paper that very night. Clay was anxious to do so, for reasons already known, and at last Tom consented, saying that it would be a short trip.

And at daybreak, when the boys awoke, the two had not returned!

CHAPTER X.—THE OLD HOUSE BY THE RIVER.

“Perhaps,” Clay suggested, as the two were about to leave the Rambler for the proposed visit to the old house where the third paper was believed to be, “it might be well to awake Case, so the boat will not remain without a guard. How long will it take us to make the visit?”

“Not longer than a couple of hours,” was the reply. “We ought to be back here before midnight. The house is close to the river.”

“Why didn’t you get it before you came on board?” demanded Clay.

“I was afraid to go there alone in the dark,” was the frank reply. “I could see more than ten million ghosts every time I thought of it.”

“Pretty vivid imagination you have!” laughed Clay. “And now,” he went on, “how are we going to get ashore without getting wet? The first thing I shall do in the morning will be to buy a small rowboat.”

“I’m wet now,” Tom grunted, “and I can swim ashore, hire a boat, and come out after you, if you have the price! I haven’t seen a cent of real money since the birth of Adam!”

“Exaggeration seems to be your failing,” Clay laughed. “Well,” he concluded, “you may go and get a boat if you care to, and can. But don’t bring a boatman with you. We don’t want any one to know that the Rambler is unguarded. It seems a pity to awake the boys, so we’ll take the risk of leaving the boat alone for a time—alone with Captain Joe and Teddy on guard!”

“The dog ought to guard the boat, all right,” suggested Tom.

“He usually does, but twice lately people have come aboard without any warning from him. One was Don, your brother, and the other was King, the deputy in search of your brother. However, he may keep awake to-night, and awake the lads if any one comes sneaking around.”

Tom reluctantly took to the water again, and soon returned with a small rowboat which he had rented from an all-night fisherman. Instead of entering the boat at once, Clay called the boy on deck and handed him a suit of dry clothes. The garments were much too large for the slender youth, but they were preferable to the wet ones he removed. Then, taking two electrics and two automatic revolvers, the two rowed to the shore, secreted the boat in a little slip, and set out for the old house by the river.

“Now,” Clay observed, as they walked along, “you might tell me something about those papers. What do they stand for, and why are they scattered so widely? Is there any one on earth who can read them?”

“The papers,” replied Tom, “refer to a locality in one of the canyons of the Colorado river. We don’t know exactly what it is they stand for. We have been told that our fortune lies there, and so we are trying to get it. It may mean gold, diamonds, copper, silver, or good advice! We never will know unless we get the third paper and go look for the thing which lies behind the big ‘X.’ It is a long story.”

“In one of the canyons of the Colorado river?” repeated Clay. “And that is the reason you two rascals decided to take passage on the Rambler! You expect us boys to take you up to your fortune?”

“We shall pay you for the trouble, you know,” falteringly.

“But suppose you don’t find anything of value there? Suppose the suggestion you recently made about good advice is the correct one? How are we to get our pay, then?” asked Clay, with assumed gravity.

“Then we’ll pay you in good advice,” was the quick reply. “The good advice will be not to take tramp boys on board your boat on the strength of any plausible fairy tale they may tell you! How’s that?”

“Where did these mysterious papers originally come from?” asked Clay, without replying to the last question, but smiling at the quick humor of the other. “Who unloaded them on you boys?”

“Uncle David Durand,” was the reply. “He was a sort of a hermit, and lived in the Grand Canyon for a long time, all alone, after we left him. I guess he lived on the fish he caught and his grouches! Every time I saw him he had fish scales on his vest front and a three-cornered grouch under his crust. He left the papers to us as an inheritance, with the warning that we'd have a beaut of a time finding our fortune! We are having all of that!”

“But you said Don stole the papers. What about that?”

“This man Josiah Trumbull stole the two first. This Josiah is a crook. He lived with Uncle David for a time, trying to worm his secret out of him, but did not succeed. Then he salted a mine and sold it to a friend of David’s for $50,000, and got out of the country, with the officers close behind him. That’s the $50,000 Don took when he stole the handbag to get the papers.”

“And you don’t know where this location is?”

“No more than a rabbit! We think it is near where Uncle lived, but we’ll find out when we get the third paper. That gives the clue to it all.”

“Who put it in the old house where we are going to look for it?”

“A paper in Trumbull’s bag located it there, that’s all I know. Don was to get it when he reached Yuma, but King was too hot after him. The boy will be glad to know that we unearthed it—if we do.”

“It seems to me to be about as clear as mud!” Clay exclaimed, and you’ll have to tell me about it at some other time. Do you see the old house by the river yet? We have been quite a time on the way.”

“It is there,” answered Tom, pointing. “You can see the roof from here. It is an old derelict, formerly occupied, ages ago, by Uncle David, now mostly given over to rats. I stood here a long time before I saw your boat and heard your voices, wondering if I had the courage to go in there alone without a gun or a light. I found that I hadn’t, and so went scouting along the river, looking for you.”

“Rats!” repeated Clay. “You say the old house is mostly given over to rats? Is that what you said a moment ago?”

“It surely is,” replied Tom. “Rats own the place now.”

“Must be a peculiar kind of rats that carry a lantern,” Clay observed. “If you look you’ll see a light passing from window to window.”

There surely was a light passing from side to side of a large room which faced the street. There were no sash in the window openings, and the large front door hung on one hinge. Taken altogether, it was as dreary-looking a structure as one would be apt to come across.

The boys made no attempt to enter the house by the front door. Instead, they passed around to the west, or river side, and vaulted through an open window which lighted a room back of the one in front. The river ran close to the foundation wall on the west, and eddied about under this window, proclaiming an unusual depth of water there. The house stood in a hollow, lower than the river, but protected by the raised bank.

Listening for sounds, watching for lights, Clay and Tom stood by the window opening a long time without hearing or seeing anything worthy of note. There was only the murmur of the waters and the uncertain light of the stars. After a time Clay whispered:

“Where is the paper you came here to find?”

“It is supposed to be in an old cupboard in the cellar,” was the reply. “It is enclosed in a wallet with other documents. I’ll show the way, as near as I can without having been over the ground since I was a little chap.”

“But why—”

Clay cut the sentence short, for he realized that that was no time or place to ask questions regarding the motives of the person who had placed the paper in such a place. Besides, he believed that the person who had shown a lantern was still in the house. Directly a creaking on the cellar stairs confirmed this opinion.

Followed by Tom, who was actually shivering with fright, he crept to the head of the cellar staircase and looked down into a dark passage. But while he looked a light sprang out and King’s face was revealed. The deputy was digging with a shovel in one corner of the cellar!

The cupboard Tom had mentioned was close to the stairs, and Clay decided that he could get to it while King worked with his shovel, seize the wallet, and get out of the house without being seen.

But King, while industrious, was always watchful. Time and again he lifted his lantern and glanced keenly around the place.

Clay started down the steps several times, but always drew back, for the least noise attracted King’s attention. The boy had no idea how the deputy had reached Yuma so soon after being put off the Rambler, or why he was digging in the old house, but all this was of less importance to him than the recovery of the paper said to be in a wallet in the old cupboard, which stood in plain sight from where he crouched, near the head of the stairs. At last King picked up his lantern and began looking in an other and more distant corner of the cellar.

Then the boys moved down the steps, gained the cupboard, and threw the door open. Three shelves were revealed, each one covered with a collection of miscellaneous articles and dust. There were cracked dishes, broken knives and forks, unknown things tied up in brown paper, and scores of such articles as a miserly man or woman might store away, not having the heart to discard them utterly. And there was the wallet!

Clay seized it eagerly and thrust it into a pocket. Then, as he reached up to make an investigation of an article on the top shelf, his foot slipped and he came near falling.

He would have fallen only that he clung to the shelf for support. But the shelf was not stable, for his body swayed back as he clung to it, and then he saw the entire interior of the cupboard swing out! The displacement of the woodwork revealed an opening in the west wall of the cellar, against which the cupboard stood.

Standing back of Clay, Tom saw King lift his lantern and move toward the stairway. If he came on discovery was certain, so the lad pushed his companion on into the dark opening and followed him.

At first Clay resented the action, for the place beyond the opening was dark, and damp gusts of wind sighed out of it, but at a whispered word from Tom he groped in and made way for his companion. The light of King’s lantern flashed almost in their faces as they turned to look out into the cellar again.

King was advancing toward them, so Clay reached out and softly drew the shelves toward the wall. There was a sharp snap, as of metal meeting metal, and then all was dark and still.

Clay brought out his electric and flashed it around the place. It was just a dungeon cut off from the cellar on the river side. The walls were of stone, and the ceiling was of iron. Through the wall on the west the murmur of the river could be heard.

“Looks to me like a miser’s vault,” Clay whispered, as he swung his electric around. “You say your Uncle David lived in this house once?”

“Yes, but that was a long time ago. He owned it at the time of his death, and, the people of Yuma say, used to visit the place once a year.”

“He might have stored gold or silver here,” Clay suggested. “This den wasn’t prepared to keep vegetables in!”

Tom went to the door and listened, having no answer to the supposition. He could hear King moving about in the cellar, and finally there came a tap on the door, which, the boy saw, was covered with a plate of rusty iron. Then a voice, muffled by wood and metal, came to his ears. It was King speaking and his tone was one of triumph.

“Good-night, boys!” the deputy said. “You are welcome to all you find in there! I’ve been over every inch of it! Good-night. I’ll see that you remain there for a time!”

“We might starve to death here, and no one would ever know!” Tom complained. “I knew Uncle David had such a hole as this, but I never thought I’d be locked up in it!”

“How do you think King found out about it?” asked Clay.

“There must have been papers Don didn’t get with the handbag,” was the reply. “I don’t know! He found out, anyway, and so did we! I suppose we are about nine thousand feet under the surface of the earth!”

“Make it a good one while you are at it,” chuckled Clay.

“How are we ever going to get out?” asked Tom. “I’m afraid down here in this musty hole! I always was afraid in the dark. I see ghosts in every shadow! Guess I was born that way!”

“We’ll have to dig out,” Clay answered. “We’ve just got to get back to the Rambler! What will the boys think?”

“Think we’ve run away, I presume.”

“Then you’ve got another presume coming! They’ll think we have been abducted and killed. So many strange things have occurred lately that they have a right to think almost anything! It is after midnight now, and I was to awaken Case at that time and go to bed.”

“We’ll both go to bed in the promised land, I guess!” Tom declared, gloomily. “I don’t see how we’re ever going to dig out of here!”

“If you’ll cast your mournful eyes over into that corner,” Clay said, “you’ll see a shovel, or a spade, or some digging implement King must have left here. I reckon we can do something with that! Do you get me?”

“I never knew that a shovel could dig through stone or iron,” observed Tom, still despondent. “You’re just trying to think you can dig out.”

“Son,” chuckled Clay, “these stones are laid on solid ground. I don’t know how deep the foundation runs below the bottom of the cellar, but, no matter about that. We’ll dig down until we get under the wall, and then the stones will come tumbling down and we’ll walk out—to the confusion of King and the great delight of the boys and Captain Joe and Teddy.”

“I’d like to know how King got up here,” Tom muttered, as Clay took up the shovel and set to work. “You said he was down the river.”

“He won’t stay put,” said Clay. “He probably attracted the attention of a steamer crew and came up ahead of us. There! Look here,” he added. “The foundation is on a level with the bottom of the cellar. I’ll have this wall tumbling in no time. Then for the Rambler before daylight.”

Clay dug away manfully, and the great stones of the wall soon began sagging down. Directly there was a line of light just under the sill of the house.

“Now we’ve got it!” laughed Clay. “Here’s light and fresh air. The moon must have come up after we came down here. See how light it is! A few more minutes, and we’ll be out of here and on our way!”

Quite a section of the wall now fell in, so that Clay had to make quick motions in order to avoid being crushed by the great rocks. Still there was insufficient space at the top to permit of their passing out.

Clay mounted the fallen stones and tried to work his way through, but found that he could not do so. When he stepped down and took up the shovel again he found himself standing in water!

The excavation he had made had connected with the river, and the cellar was being flooded!

CHAPTER XI.—ALEX GETS HIS RECEIPT.

When Alex and Case awoke at daylight and discovered Clay’s absence, they began a search of the shore with their glass, supposing that he had gone into the city for supplies. Then Alex discovered the remains of Tom’s supper, and Case came across the clothing taken off by the lad. The clothes were still wet.

“There’s something queer been going on here!” Case exclaimed. “Clay had a visitor who swam out to the boat last night!”

“And the guest had supper here!” Alex contributed. “And Clay must have gone away with him. Wonder he wouldn’t have awakened us before leaving the boat!”

While the boys cooked breakfast, discussing the remarkable disappearance of Clay as they did so, a boat bumped against the prow of the Rambler and a voice called out:

“Hello, there! Where’s my rowboat?”

Alex, leaning over the railing, saw a swarthy face looking up at him. The fellow seemed to be angry for he was swearing and gesticulating wildly.

“If you think I’ve got your boat you may search me!” the boy said.

“But you got it last night!” insisted the other. “You rented it for an hour and never brought it back. What have you done with it?”

“Guess again!” Alex replied. “I slept all night. Never saw your old boat. It was some one else who rented it.”

“Well, the boy who got it said he wanted to bring a friend off this boat, and that he would return it before midnight.”

“You’ve been buncoed!” Alex laughed.

“Wait a minute,” Case broke in. “There may be something to this. You say a boy got a boat of you to row out to the Rambler?” he asked of the man, now getting ready to board the boat and make physical trouble for the boys.

“That’s what I said. Where is that boy now?” “What sort of a looking boy was it?” asked Case, patiently.

“A little bit of a chap. He was wet as a rat, and said he had swum off this boat and wanted to row out to bring a friend off.”

“Well, did you watch him after he left with the boat?”

“Yes, and he came out here; and then another boy got into the boat with him and they rowed ashore. I want my boat or good pay for it—right now!”

“If you come up here with your threats,” Alex declared, “you’ll get a rap over the head—and I’ll set the dog on you!”

“I’ll have you all arrested!” shouted the other. “I want my boat.”

“Sing it!” chuckled Alex. “You might make a fine song with that ‘I want my boat’ story of yours. Have you looked along the river bank for it? The boy might have left it there.”

“I have not,” was the reply. “It is up to you to return it, and not my place to look for it. That boat was worth $50 of any man’s money.”

“Will you wait a moment, please?” Case asked of the boatman, as he drew Alex to one side. “I may want to go to shore with you before long.”

The other nodded and stood angrily in his boat, waiting.

“Now,” Case explained to Alex, “there is no need of making an enemy of this man with your impudent talk. He is probably right. Some one swam out here, had supper, swam back and got a boat, and took Clay to the shore. Now, who could it have been? This beats me?”

“Couldn’t have been Don, could it?” asked Alex, doubtfully.

“I’m all at sea,” Case replied. “I don’t understand how Don could have got up to Yuma, and yet I’m half inclined to believe that it was he who took the money, though why he should have done so without letting us know is more than I can figure out.”

“There’s no head or tail to this business,” Alex declared. “We’re all mixed up with other folks’ troubles, just as we were on the Amazon and Columbia river trips! Are you going ashore with this man?”

“Of course. I’ve got to find out, if I can, where Clay went.”

“Of course we’ve got to do that.” Alex agreed, “but don’t you go to mixing with any one else!

Bring Clay aboard and we’ll fly up the river like little birds! I don’t want to see any one else for a month! The river and the mountains and the canyons will do for mine!”

“That’s just the way I feel about it,” Case replied. “I’m tired of mixing in affairs that don’t concern me. I want to get up the river and be let alone. I hope Don will find his money, but I’m not going to bother my head any more about it.”

“That’s me!” Alex agreed. “You go ashore and get Clay. He’s not far off. Take Captain Joe with you. He will follow the boy’s track from the place where he landed. And when you get Clay, make a run for the Rambler! Don’t stop, even to pick up money, until you get on board, then we’ll shoot up stream like a shark after a pig! No more of this for me.”

So, after further talk, Case went ashore with the boatman, and Alex got out his automatic and sat watching the river bank. Teddy stood up on his hind legs and invited the boy to a boxing match, but he was too blue and too anxious to play with the cub.

“I wonder if Don did get that money?” he thought, over and over again as he sat watching the shore. “If he did, why didn’t he let me know that he was taking it?”

He could find no answers to his questions, so he studied the shore of the river where the town loomed up and wished from the bottom of his heart that his friends were on board, and that the Rambler was a hundred miles away from King, Don, and all the rest! Then he heard a hail from the river and ran to the prow.

A small boat lay rocking in the current, and out of it looked the grinning face of Don Durand! Alex almost dropped over the side in his amazement. Now that the boy was before his eyes, however, he was unaffectedly glad to see him.

He tossed down a rope end so Don could secure his boat to the rail of the Rambler and, later, gave him a helping hand. When Don gained the deck he received a cordial greeting.

“Can you get me out of sight, quickly?” the boy asked. “King is in Yuma, ‘and he’s goin’ to get me if I don’t watch out!’”

“Of course I’ll help you,” Alex answered. “I don’t like your ways, but I’m sore on King. He came on board and mussed up the furniture and tied up the dog, and marooned Clay and Case on a desert island!”

“That must have been nice!” Don grinned, going to a heap of pancakes which had been cooked for breakfast and left to grow cold because of the excitement of the time. “I’m going to eat these few dozen pancakes while you converse!” he added. “Why don’t you like my ways?”

“Eat away!” Alex returned. “You’re always hungry when you come on board the Rambler. “I’ll get you coffee in a short time.”

“There’s nothing to eat in the desert,” Don said, stuffing his mouth with cakes. “Besides, I’m going to board with you all the way up the Colorado, so I may as well begin now to make you acquainted with my appetite. But you didn’t tell me why you don’t like my ways.”

“Why didn’t you let us know you took the money?” asked Alex, at a venture, almost trembling as he awaited a reply.

“Didn’t you get my receipt for it?” asked Don. “It was on the silk wrapper. I wrote in there! Where is the wrapper?”

Alex took the silk from a pocket and examined it. Surely enough, there, on the edge, were the words: “Received contents. Don.”

“Why, you old fraud!” shouted Alex, overjoyed at the discovery. “You old river thief! Why didn’t you wake us up and tell us you were after the money? You’ve made us a lot of trouble!”

Don grinned and continued his work on the cakes, and Alex finally put the coffee pot over the coils and made him a cup of hot drink while he told of running across the point and floating down to the Rambler on a plank he found in the water. Alex grabbed him, then, and demanded to know where the money was.

“Let go!” yelled Don. “I’ve got it in my belt, and I didn’t want any one but you to know I took it because I didn’t want the others to know where it was, if anybody should come on board and ask about it, and, then,” he went on, with a sly wink, “I made the receipt a little blind because I wanted to teach you not to go to sleep with fifty thousand dollars in gold notes lying in your lap! That was careless of you!”

“The notes were in the silk covering, in my pocket,” insisted the boy.

“Well, perhaps they were, at one time, but Teddy was about to investigate the package when I crawled up out of the water, off the plank I’d floated down on! Now, tell me about King coming on board, and what he did and said.”

“He must have landed on the Rambler from a small boat dropped off a river steamer,” Alex answered, still so pleased with the news that the money was safe that he could hardly talk straight, “and he came in the night.”

“And no one saw him? What about the dog’s giving an alarm?”

“We have figured that out. King had been on board before, and had been treated kindly, so the dog probably thought he had a right to come back. But he insulted Captain Joe, after he got on the deck, for he tied him up. He won’t get on here again right away. Joe will eat him up if he tries to.”

Then the boy told of the manner in which Teddy had gotten rid of the unwelcome visitor, and Don began to make inquiries for Case and Clay. Alex had to tell him about that, too, and Don looked frightened at the recital.

“The boatman said it was a little bit of a fellow?” he asked. “Then that was my brother, Tom! I was to meet him here, after King got out of the way. Now, where do you think they are?”

“I don’t try to think any more,” was the reply.

“I believe I know where they went,” Don burst out, in a moment. “They went to the basement of an old house owned by my uncle, and something has happened to them to prevent their coming back.”

“If you know where they went, suppose you go bring them back.”

“And run plump into King! Not for mine. You go! I’ll tell you where the house is, and you can go and bring them back.”

“If King hasn’t arrested them, perhaps I can,” Alex added. “He may have caught them, you know. Well, where do I go? I’ll make a bluff at finding the boys, and then we’ll go on up the river. Trouble is too thick down in this country! Show me where the house is.”

“You see that old tumble-down structure on the river bank, just a little below the city?” asked Don. “Well, that’s it.”

“What would they go there for?” demanded the other. “More mystery!”

“They will tell you that! Now, while you are gone, I’ll fry more cakes and get a good breakfast. I’m going up the Colorado with you, you know, and I may as well begin to make myself useful.”

“You say it well!” returned Alex, but he did not appear to be much annoyed at the thought of taking on this agreeable passenger.

Alex descended into the rowboat and cast off. Then he stood up, excitedly, and pointed to the old building Don had designated.

“What’s the matter with the old barn?” he called out. “Get the glass and look at it. It seems to me to be tumbling into the river.”

“It surely is!” Don cried, looking through the glass. “There’s been something exciting going on there, and the old house is sliding into the water. I guess I’d better go ashore with you!”

“No you don’t!” the boy answered. “You’re going to guard the boat while I find out about this. If King comes on board, set Teddy at him!”

“No one will pick money off me while I’m asleep!” roared Don.

Alex made good time to the shore, but when he reached the little pier which ran out just south of the junction of the Colorado and Gila rivers he found a crowd ahead of him. The old house was just below, and the creaking of parting timbers told of rapid disintegration.

“What is the trouble?” he asked of the first man he met after landing.

“Why, the old Durand place is tumbling down,” was the reply, “going into the river! It is believed that large sums of money are hidden in the old miser’s den, and the people are flocking here to see if they can snatch some of it. Doesn’t look now as if any one would get it!”

“Some of the folks here may be after money,” another on-looker cut in, “but most of them are watching to see if the boys get out alive. They say there are two young boys locked up in an iron room down there.”

“How do you know that?” demanded Alex, his heart in his throat.

Before the other could answer the question Case came running up.

“Clay and another boy are in there!” he cried, wringing Alex’s hand. “They are locked in a deep cellar, with water pouring in on them! If they don’t drown, the falling walls will kill them!”

“How do you know they are in there?” Alex asked, hoping to find the story told by the on-looker and by Case an uncertain one, after all.

“King came for help to get them out, when he found the cellar was filling with water,” Case answered. “He said he had arrested them and put them in the den for safe keeping. He admitted that his act of authority might be the death of the boys, and he would have been lynched if he hadn’t run away. How are we ever going to get them out?”

While they stood there in an excited, anxious group Don came panting up, wet from a swim from the Rambler. Alex began grumbling because the boat had been left alone, but Don stopped him.

“I heard what they are saying about the iron room,” Don said, “and the boys being locked in there! I used to know the location of the spring that opened that door from the cellar, but I can’t think of it now. If I only could!” he cried beating his forehead with his fists.

The old house was tumbling fast. The thin bank which ran along the river side was now caving, and the ground around the structure, which was considerably lower than the surface of the river, was being flooded. Captain Joe pulled at Alex’s leg, drawing him toward the house!

“I’m going in there to try to find the spring,” Don said, but as the three lads started for the crumbling old house the officious crowd seized and drew them back!

CHAPTER XII.—ANOTHER GREAT DISAPPOINTMENT.

At first the incoming water seeped through the bank of the river, under the surface, as Clay’s excavation had cut almost through the narrow bulk of earth between the house and the water’s edge. Then, as the underground current carried earth with it, undermining the bank, the cellar began to fill from the surface and the line of light under the sills became simply an aperture for the delivery of water into the basement of the old house.

“This is getting serious!” Clay exclaimed, as the cellar filled to the depth of a foot or more. “We’ve got to do something right off or we’ll be drowned like rats in a trap!”

“I learned once, when a kid, how to open this iron door from the inside,” Tom announced, “but I have forgotten. We lived with Uncle David for a time, Don and I, until he became too stingy to buy food and clothing for us, and one day he showed us all about this treasure room, as he called it. Don remembered, but I did not. If Don were only here now!”

Clay turned his electric light on the door, weaving it over every inch of the iron sheathing and the stone walls on each side.

“If there’s a spring or anything of that kind here, we ought to be able to find it,” he declared. “Was it down low or up high. You were a little shaver then, did you stand up in a chair to reach it, or did you bend down to the floor? You ought to be able to remember.”

“But I can’t!” groaned Tom. “I’m afraid! I always was afraid in this old house. Uncle said there were ghosts in the cellar! I’ll never get over my dread of the place—never! What shall we do?”

“Keep poking at everything you see,” commanded Clay, annoyed at the boy’s attitude. “There must be something to push, or something to pull. We are certain to find it if we keep on looking. We never came to this country to be drowned like this! Bet your life we never did!”

“But the water is getting deeper every minute,” wailed Tom. “Oh, I can fight out in the open, and like it, too, but I’m terrified in the dark and in places where strength doesn’t count!”

“Courage always counts!” Clay answered. “You just keep on looking for that spring, or that lever, or whatever it is that opens the door!”

The lads did keep on looking, but the water rose higher and higher. They could now hear voices outside, though they came dully to their ears, and now and then a crash came which told of falling timbers.

Clay realized that the foundations of the house were falling in more places than one, and that the sills and studding were giving way, but he did not care to inform Tom of this new peril. He knew that the boy was not lacking in courage, as courage is usually classed, but he also knew he possessed the same natural antipathy to darkness that the house cat possesses for water. Probably because of prenatal influences, the boy was a coward at the present time, though he tried hard not to show just how hopeless, and frightened, and despairing he was.

“There’s a crowd gathering outside,” Clay encouraged, “and they’ll find some way to get us out. But we’ve got to keep on looking for the means to open this door. Why, boy, just look here, will you?”

Clay was pulling at a half-concealed lever which he had found pressed into a niche in the stone wall as he spoke. It came out slowly and a stone above it moved as he drew it away from its hiding-place “I thought I had it!” he cried. “It moves something, but not the door! Queer old trap, this! Look at it!”

As the lever came out a stone in the wall started from above and dropped down on hinges, revealing an opening about a foot in size.

The boy held his light to the opening for a moment and then drew out a thick package of papers. One end of the wrapper had been torn off, and Clay drew a paper out and looked at the lettering on the back of the fold. Then he thrust the papers into an inside pocket and looked Tom in the face, his own eyes staring with amazement.

“What is it?” asked Tom. “What did you find?”

“Government bonds!” Clay almost shouted. “There are thousands of dollars’ worth in that package! Think of drowning with all that wealth in sight! Buck up, young fellow! You’ll soon be a rich man!”

“I was in hopes the lever opened the door!” Tom muttered. “I’m not interested in government bonds just now! What good would a million do us if they found us dead here on this floor?”

“You give me that tired feeling!” Clay exclaimed. “Keep on looking for the lever or key which opens the door! Listen! Do you know that voice?” he added. “That’s Captain Joe, and he’s telling us that he is on his way to the rescue! Clever old dog, that Captain Joe!”

The boys searched every square foot of the walls, even reaching up to the ceiling, but found nothing which would open the door. The water rose steadily, and the voices outside gradually grew fainter.

Now the water was up to their hips, now to their waists, now it came to their arm-pits, now Tom was obliged to stand up on an old chest to keep his head dry. All around them the building was falling, but nothing seemed to disturb the iron ceiling above.

The walls of the cellar were falling, too, in places, but they only crumpled down in great heaps of stones, leaving no opening through which the boys might make their way to the free air outside. It was now broad daylight outside, but the flashlights were still needed in the cellar.

“We’ve got about a minute more!” Clay admitted, as the water touched his chin. “We’re up against it at last! I’d like to leave a note for the boys, but it is too late to write one now. Hear Captain Joe out there? Say, old sport, I believe he is coming nearer! He surely is! Hurrah!”

Then the iron door swung open and, the water being somewhat higher in the den than in other parts of the basement, a strong current set toward the east, lowering the flood a foot or more where the boys stood.

First, they saw Captain Joe’s ugly head poking through the water which filled the doorway. Then Don’s face showed. However, there was a current setting toward the main basement from the den, and both the boy and the dog were forced back.

The outsweep of water had lowered the body of it in the den, so that the boys were no longer in danger of drowning, but they knew that in time the little apartment would fill again, as the main cellar filled. Clay took Tom by the shoulder and pushed him to the doorway.

“Dive through!” he said, “and when you get out into the cellar make for the stairs and climb up. This old shack will be afloat in no time! Hurry, now! Perhaps Captain Joe will help you if you tumble down!”

Tom shivered and hesitated until Clay became angry.

“All right!” he said. “I’ll go first. You keep close to me!”

And so the lads dove through the doorway, groped, half strangled, up the stairs, over fallen timbers and planks, and so on into the main hall, where there was no water as yet, but where the floor was sagging because of the washed-out foundations.

Case, Alex, and Don were there to meet them. Outside the crowd was cheering wildly and shouting congratulations to the boys who had entered the flooded basement to open the door.

Clay and Tom began expressing their gratitude and their appreciation of the brave act, but Don cut them off with a question.

“Did you get the wallet?” he asked.

“Of course we did!” replied Clay, “and we got something else, too.”

“What else was there to get?” asked Don.

“Mighty little left in that old house the last time I was there.”

“You’ll see, in time!” Tom said, with a knowing wink at Clay.

“Explanations in the future!” Clay exclaimed. “Just now we’ve got to get past that sympathetic crowd and back to the boat. Say, Don,” he added, in a moment, “I can’t wait to get back to the Rambler before asking one question, and that is this: Did you come aboard the Rambler and get the money? If you did, say so—quick!”

“I certainly did!” Don answered. “If I hadn’t would have been lost, for Teddy was playing with it!”

“That’s enough!” Clay said. “I’ll learn how and why later on. Wonder if King is in that crowd out there? It was he who locked us in.”

“He is not,” grinned Case. “The mob got after him for locking you up in such a dangerous hole, and he took to his heels! He won’t dare show himself around here for a few days.”

“Then all we have to do is to get rid of the crowd,” Clay explained.

Of course there were many who wished to shake hands with the rescuers and the rescued, and even Captain Joe came in for a fair share of praise, but the boys were soon out of the crowd and on their way to the boat.

At the water front they found the riverman, still growling and sulking over the loss of the boat Tom had hired the night before. Tom told him where the boat had been left, and Clay paid him for the use of it, so he eagerly consented to row the boys to the Rambler, and, later on, to convey their provisions and gasoline to them.

“I’m glad we find the boat still here!” Alex said, as he mounted to the deck, “and I’m glad we have gotten rid of King. Now for a trip up the river! Now for freedom from sleuths and mysteries!”

The other boys echoed the sentiment, but when they opened the cabin door, a moment later, and looked in, there sat King, busy with the cold pancakes Don had cooked just before he left the boat to assist in the rescue of Clay and Tom. He smiled as the boys entered.

“Well, of all the iron nerve—”

Alex could not finish the sentence. There were no words which could do justice to the occasion, he thought.

“Help yourself!” Clay said. “If you’ll wait a little while we’ll give you hot coffee. We’re going to make some for ourselves!”

Tom’s greeting was not so cordial.

“If this was my boat,” he said, “I’d break you in two with my foot. You came near drowning us. Do you know that?”

“The people on shore told me!” smiled King. “They came near stringing me up by the neck for what I did.”

“You deserved it!” grumbled Don. “Indeed you did.”

“Now, see here, boys,” King went on, “I had my duty as an officer to do. If you had been relieved of fifty thousand dollars and valuable papers, you would expect the law to get them for you, wouldn’t you?”

No one replied, and the officer went on, calmly eating cold cakes as he did so—eating and tossing a piece to Teddy now and then.

“You see,” he resumed, “I hold no grudge against the bear, if he did dump me into the river! He did just what I would have done under the circumstances. I don’t blame him. He is a good little beastie!”

“You wasn’t helping the law any by locking us in there to be drowned!” Clay remarked, his eyes flashing.

“Wasn’t I?” asked King. “Let us see about that. You, Don, took fifty thousand dollars of another man’s money out of Chicago. You carried it in a belt about your waist. I had to find that money, didn’t I? I searched the Rambler for it! I had to maroon two of the boys on a sand island and tie Captain Joe up in order to do it.”

Captain Joe licked his chops as if he was thinking of making settlement for the insult right there. Clay called him away, or he would have taken hold of the deputy’s leg.

“Yes, I searched the Rambler, and got up-river in a steamer after being dumped off. Here I heard that lights had been seen in the old house the night before. Now, what was more reasonable than to suppose that Don had visited the old shack and buried the money in the cellar? I was there looking for it when you boys came in. I should have released you as soon as I had finished my search, only I couldn’t unlock the door. All I could do was to go for assistance, and you all know how that came out. I nearly lost my life at the hands of a mob, any member of which would have done exactly as I had done.”

“You say it well!” snarled Tom. “I don’t trust you, though!”

“Now,” King continued, without taking notice of the remark, “I’ll tell you what I’ll do. I understand that there is a question as to whom this money belongs. It may belong to Don, for all I know! Well, if you will put the cash in the hands of a banker here I’ll go back home and say nothing about the deal until you boys have had time to turn around. But I want it understood, too, that my client, this Josiah Trumbull, is not to be molested by you for anything he has done in the past.”

Don agreed to this, and King continued.

“I have a notion that my client is a roughneck, as well as a three-card sharp, but I’m going to do the best I can for him, for all that. If it can be shown that the money belongs to you, Don, or to you, Tom, it shall be turned over to you. But if this cannot be shown, Trumbull is to have it, as against any other claimant. Is that right?”

This was reluctantly agreed to, and then the boys and King prepared the best meal the larder was capable of, and enjoyed it hugely. After this they went to the town, leaving Tom and Clay on board, and the money was put in escrow in one of the banks. Don also put the government bonds on deposit there. King’s eye stuck out when he saw the bonds and was told where they had been found, but he only expressed congratulations.

All this business completed, provisions and gasoline bought, and letters sent away, the boys went back to the Rambler to study up the three mysterious papers as forming a whole. But the black wallet held no paper of any kind! There were a few half-rotten banknotes in it, a small flat key, and nothing else!

“We are up against it again!” cried Case. “Well,” with a smile, “we’ll go right on and try to uncover the mystery without the third piece of paper. I wonder what this key fits, and if King got that third paper? He might! What?”

CHAPTER XIII.—ALEX PLANS A NIGHT ADVENTURE.

The boys talked over the possibility of King having the third paper for a long time. They could not see how the deputy had been able to secure it, if he had done so, unless he had discovered it in the cellar, which seemed to them to be highly improbable.

“That uncle of yours must have been a quaint old chap,” Clay said, laughingly. “How, for instance, did he know that you would ever find the bonds in the strong room?”

“I’m sure that he left a paper somewhere which tells about them,” was the boy’s reply. “Perhaps this third paper will unravel the whole mystery. Uncle told us about some papers the last time we saw him at the shack in the Grand Canyon, but he did not tell us where they were. He said we would find them after he was dead. I believe that all the papers were left in a letter for us, and that this man Trumbull stole it.”

“How do you account for his having a chance to get them?”

“He was there, in the canyon, living near Uncle, when the latter died—suddenly and alone, and was the first one there, the others say. It is said, too, that a letter was left for us, and that it disappeared. I knew Trumbull to be a thief, because he salted a mine and sold it, so I naturally suspected him of taking the letter. This is how I came to get the two papers and the money!”

“How did you come to find Trumbull in Chicago? All this is very interesting to me. Wasn’t that a long chance—to find him at all?”

“We were in Chicago, earning our own living, when Uncle died. The people living near the canyon wrote us about Uncle’s death, and about this man Trumbull being there, and about the disappearance of the letter. I thought the letter might have contained the promised papers, and so watched for Trumbull, never expecting to see him there, though!”

“But you did find him! However did it happen?”

“After being in Chicago a short time, I got a position as errand boy in a bank. I suspected at the time I got the place that the manager took more than the usual interest in me, and I thought that he might know Uncle David. That was before Uncle died, you see.

“Well, the manager took me on as errand boy, but after a time he kept me working for him, and about his own private office in the bank, most of the time, and often asked me about my uncle’s affairs, of which I could tell him nothing, of course. I had not been there very long when Josiah Trumbull came into the private office one day and laid a mining proposition before the manager.

“I heard some of the talk, and discovered who he was, and also learned that the mine he proposed developing was in the Grand Canyon of the Colorado. He said it had been proven that the ore was virtually inexhaustible, and added that he had come upon papers which showed him where it was. The location was in the part of the canyon where Uncle had lived.

“Then I recalled the talk Uncle David had had with me about valuable documents, every word of it! I recalled, too, that that this man Trumbull had been suspected of taking the letter! I watched him closely, you may be sure! Quite like a detective story, eh?”

“It may prove to be one before the end is reached,” Clay said. “Go on! I’m more interested than I can tell you!”

“Well, one day Trumbull came into the private office with a handbag and set it down on a desk. He said he had drawn a little money and had placed the papers he had spoken of with it. He added that he was going out to the canyon mine to look into the matter.

“I stole that bag. I did not know that it contained a large sum of money. I knew only that it contained the papers I wanted. By this time, you see, I was certain that Trumbull had stolen the papers, that the papers concerned a mine, and that he was about to acquire what belonged to Tom and myself.

“I escaped, as you know. Just how I’ll not tell you now. I should have consulted the manager, but ran off without doing so. That same day I read in the newspapers about you boys and the Rambler. You see, I had no money, save the $50,000, and I would not touch that, so I planned to get to the Gulf of California and go up the Colorado with you! Tom was crazy about it, and we started away. You know what wretched objects we were when we came up with you.”

“But what got the notion into your head that the third paper was in the wallet in the old cellar?” asked Alex.

“One day Uncle David told me of the old house being empty and in the last stages of decay. We had visited the place with him, earlier, you see, and I knew something about the treasure room. He had always told me, though, that no money or thing of value would be found there. He said that I must work for all I got of him.

“He said, though, that I might find some good advice in the treasure room after he was dead. I did go there, with Tom, on my way to Chicago, after we left him, but discovered nothing. I had even forgotten the manner of getting into the treasure room. But when I found the two papers in Trumbull’s bag I at once drew the conclusion that the third paper must be in an old wallet Uncle had referred to as being in the old cupboard. I was pretty sure it would be found there, as you know. The only question in my mind was as to whether I should be able to get into the treasure room and make a search of it without tearing the house down. Tom did not know of this difficulty, and I never told him.”

“You’re telling me now!” laughed Tom.

“When we got to Yuma,” Don went on, “we were too busy dodging King to do much investigating at the old house. Trumbull must have told King about it, for he watched the place, as you know, and even dug there for treasure. Tom and I got separated on the way across, and King saw me while I was waiting for Tom to come up.

“When he did come, I left him there and went on down the river to connect with you. There was nothing Tom could be arrested for. Now, that’s how I got the money and the two papers, and also how I didn’t get the third paper!” the boy laughed, “and so we’ll talk about something else if you don’t mind.”

“But how are you ever to get this third paper, and how are you to get the treasure if you don’t?” asked Case.

“With your permission I’ll go on up with you to where Uncle used to live and search his old shack. The third paper may be there. Of course the bonds are what Uncle David referred to as ‘good advice’ in the treasure room. That was just like him, to call bonds ‘good advice.’ If I ever discover the third paper, I have no doubt it will tell me where to look for the bonds. He never thought of their being found in the manner Clay found them!”

“Where did you ever hear anything about a third paper?” asked Clay.

Don took the original papers holding the drawings out of the belt and held it up to the light.

“Did you see this line at the bottom?” he asked. Alex gave a start of surprise. He had studied every figure and letter on the paper and had seen no line at the bottom, yet there it was, plain to see when the paper was held up to the sun. The line read:

“Worthless without No. 3!”

“There you are,” Don went on. ‘Worthless without No. 3.’ Josiah Trumbull and King found that line, and they are, or were, hunting for No. 3, just the same as we are! Now, if you boys think this mystery will spoil your trip, just put us off and we’ll get to the canyons some other way, but, still, we’d like to go with you!”

“I’m so seriously interested in the mystery,” smiled Clay, “that I wouldn’t feel like making the trip, now, without you and the two pieces of paper. How do you feel about it, boys?”

How did they feel about it? What would two healthy boys naturally say to a mysterious adventure of the sort proposed? Hunting for the buried gold of Captain Kidd looked like a summer afternoon game of marbles compared to this! The Grand Canyon and a mystery! Marks on a rock, perhaps thousands of feet below the level of the plateau! A missing paper and a contest as to who should get to it first! Surely, no game could be more exciting. And the boys said so, and all shook hands on the proposition, after which they ate dinner and Clay went on shore to see about buying gasoline, provisions and a small rowboat.

He returned just before nightfall, perspiring with the heat of the desert sun, and the articles he had bought were soon on board.

“I saw the last of King,” he reported. “At least the last of him for some days to come, as he took train for Phoenix. He’s a good sort, is King, but if he thinks his conscience will hurt if he doesn’t know more about the secrets of the Grand Canyon, he’ll hire a motor boat and follow us. I imagine he has telegraphed to Trumbull, for I saw him waiting at the office for a message. I heard him tell the clerk in the office to query Chicago.”

“Good luck to him!” laughed Don. “He is loyal to that thief of a Trumbull, all right, for he made us promise not to prosecute him if it should be discovered that he had committed some crime in connection with his dealings with Uncle David, also to restore the money to him if it did not prove to belong to Tom and myself.”

“Some one ought to be in Chicago, watching Trumbull,” suggested Tom. “Suppose I go? I can get there if the rods hold out! What do you say?”

“It would be a great idea,” Don agreed, “but we have had enough of riding on the rods, and we have no money.”

“But the bonds!” laughed Alex. “What about them? How much are they worth, Clay?” he added. “You handled them.”

“Something over one hundred thousand,” was Clay’s reply, “but there is no proof that they belong to Don and Tom, you know.”

“That’s why I put them in bank,” Don cut in.

“If you think you ought to go back to Chicago, Tom,” Clay said, “I’ll furnish the money. But what can you do there?”

“He can go to the manager of the bank where I worked,” Don explained, “and tell him the whole story, and he’ll help. I believe that manager knows more about this matter than he pretends to!”

“How did you manage to get into that bank in the first place?” asked Alex. “It ain’t every street boy that gets such a chance.”

“Oh, I met one of the bank’s messengers one day, and he told me I might get a job there. Odd, wasn’t it?”

Clay broke into a roar of laughter, whereat Don assumed a manner of wounded dignity and walked away.

“Come back here, you foolish lad!” Clay called. “You may be sure that manager does know more about this matter than he pretends to know! The chances are that he had been keeping track of you for a long time, just to see what kind of a boy you were!”

“Then why didn’t he help me?” asked Don.

“How do you know what your uncle told him to do? I reckon this Uncle David of yours knew what he was about! He didn’t want you and Tom spoiled by inheriting a lot of money! He wanted you to dig it up!”

“Yes,” replied Don, mournfully, “and I guess he buried it so deep that no one will ever be able to dig it up!”

“Anyway, you two boys have shown the proper spirit,” Case said, “and that ought to count for much. And you have the bonds!”

So it was arranged that Tom should go to Chicago that night and go to the banker and tell him the part of the story he did not know. The parting was a grave one, for the brothers were deeply attached to each other, and there was no knowing what perils would confront either of them before they met again.

After supper the Rambler was speeded up the river for twenty miles or more, “to get her out of the odor of trouble,” as Alex expressed it.

“Now,” Clay declared, when they came to anchor below Norton, with Chimney Peak showing not far away, “we are going to have a night free from boarders and troubles about money. We are off in good earnest at last.”

“That’s a pretty tolerable old mountain,” Alex declared, pointing to Chimney Peak. “I’d like to take a spin over to it.”

“You’ll stay right on this boat,” ordered Clay. “I’m not going to lose any time hunting you up.”

“I won’t get lost in any cellar!” returned Alex, with one of his provoking grins.

It was agreed that Case should stand guard that night, and the others went to their bunks early, with the exception of Captain Joe, who took his station on the prow and watched the slow-moving water with a meditative air. Teddy tried for a time to engage him in a boxing contest, but the dog declined with thanks and continued his inspection of the river.

It was a beautiful starlit night, and Alex was too full of the old spirit of adventure to sleep. He tumbled about in his bunk for a time and then arose and peered out on deck.

Captain Joe was still on sentinel duty, but Case was actually asleep in his chair! The boy was worn out with the excitement and worry of the day. Alex did not disturb him, but sat down by his side and looked longingly off toward Chimney Peak.

“Captain Joe!” he finally whispered.

The dog pricked up his ears and walked sedately up to the boy.

“Will you remain here and watch the boat while I go ashore?” asked Alex, patting the dog on his head. “Will you, old top?”

Captain Joe looked off toward the mountain summit and made no rash promises! He was a wise dog, and knew the ways of boys!

“It is just this way, Captain Joe,” Alex went on, talking to the bulldog as if he understood every word, “it is just this way. Those sleepy heads in the cabin, and this one out on deck, would sleep in the presence of the pyramids! You know it, don’t you?”

The dog said that he did in a tongue which Alex understood.

“Well, then we’ll go ashore and see what that hill is made of,” the boy went on. “We’ll take the rowboat and pay a visit to the Chimney!” It looks pretty classy from here, eh?”

Captain Joe admitted that it did, and the boy got out the rowboat and left the Rambler, the dog sitting in the prow with an air of being necessary to the expedition. The boy and the dog saw adventure ahead and were recklessly, foolishly glad of it!

CHAPTER XIV.—A VISIT FROM RIVER PIRATES.

Case slept a long time in his chair on the deck of the Rambler. The currents pulled at the anchor chain, and now and then a floating derelict of a log or discarded box bumped against the sharp-nosed prow, but the boy was tired, mentally and physically, and did not mind in the least.

Teddy, the bear cub, nosed close to him, seeking physical warmth from the chill of the night, and finally went to sleep himself. When Alex and Captain Joe looked back from the rim of sand which lay between the shore line and Chimney Peak, there were no lights to be seen on board the motor boat—only the bulk of the craft outlined against a starlit sky.

Finally, when Case did awake, it was with a sense of impending danger. There is a quality in the human brain which stirs at the vibrations of a hostile influence, and Case felt it now.

It was not long before he understood this threat fully, for his chair was knocked from under his body and he fell with a bump on the deck, lighting on Teddy, who set up a most dismal howling. While the cub scrambled out from under the boy’s legs, there came a commotion in the cabin. Case tried to get up, for he knew that a struggle was on there.

But he was not permitted to get up. There was a strong hand at his throat and a knee which dripped water on his chest.

“All right!” some one said, in the direction of the cabin.

“All right here!” the figure above Case replied, and then the boy was jerked to his feet. “I’ll bring him along in. Get a move on, kid!”

At first Case thought it was King’s voice, but in a second he saw that it was not, for the fellow broke into a series of oaths and cries of pain as Teddy seized him by the leg and set his sharp teeth together.

“Come out here!” the fellow shouted. “Come out here and kill this bear! He’s chewing my leg off. Hurry up! Bring a gun, too!”

There was a movement in the cabin and the door opened. Case saw that Clay and Don were in no better shape to prevent the murder of the cub than himself. He was afraid that the little bear had used his teeth once too often. But Case usually acted on the theory that a game is never out until it is played out, and he did so on this occasion.

“Take a swim, Teddy!” he shouted to the bear, giving him a push with one foot. “Take a run and jump into the river. Get busy now!”

The cub had often heard these words. When the boys were ready for a river bath Teddy was usually ready, too, and he was always addressed in the words Case used now, or some almost exactly like them.

So the bear, thinking, doubtless, that a new game was on, gave one parting snap at the fellow’s leg and went headfirst into the river. Case tripped the man who ran to the railing with a revolver in his hand, and was rewarded by a violent blow on the head.

“Coming! Coming, Teddy! Get a move on!” Case called out to the bear, and it was with a good deal of satisfaction that he heard the intelligent animal snorting with the race spirit as he made clumsily for the shore. Doubtless the bear wondered why Case was not at his heels on this, as on other occasions, but he kept on swimming and so escaped death.

Dazed as he was by the blow he had received, Case heard the fellow shooting at Teddy, and heard Clay and Don arguing with the men who were the cause of the commotion in the cabin.

“Come!” the boy heard a hoarse voice saying, “we have no time to lose. “You boys went to a bank at Yuma to-day and drew out a lot of money and a package of government bonds. We want them! Produce!”

“You are mistaken,” Clay replied, his voice sounding harsh and strained, as if he was just out of a struggle. “We put our money in the bank, and the bonds in the bank. We drew nothing out. Take what I have in my pocket and go. There’s nothing else here for you.”

Case heard one of the men rattling the coal stove, and a shudder of horror went through him. Would the midnight raiders be brutal enough to resort to torture? He had heard of terrible, inhuman things that river pirates had done. He tried to get up, but was held fast.

“Here!” a voice in the cabin said. “Don’t wait to heat up that old stove! Just turn the electric current on this coil. That will prevent his going to bed with cold feet to-night!”

“He is telling the truth about the money and bonds,” Case said to his captor. “They were left in the bank at Yuma, and he gave another lad money enough to get to Chicago, so we're about broke.”

“Tell that to the marines!” chuckled the other. “We know what we are doing, all right. You were seen to take the money away from the Yuma bank! He’ll remember about it as soon as the coils get hot, too!”

“Some one lied to you about the transaction at the bank,” Case insisted. “Who said we took the money and bonds away?”

“I wish I had that fool bear back here!” Case’s captor snarled. “I’d burn his teeth out of his head! I shall be lame for a month.”

“Who told you we took the money and bonds away?” persisted the boy.

“Why, an old gentleman who stood close by saw you, and we heard him speaking about it later. He said it wasn’t safe for boys like you to have so much ready money in this wild country, and we agreed with him. So we are going to help you take care of it. You’ll hear that fresh kid inside telling the truth as soon as his feet touch the hot coils.”

“If you brutes burn Clay,” Case declared, “we’ll give up our trip up the river and follow you to the end of the world but we’ll bring you to the gallows! You just remember that!”

“You’ll crow lower when your own feet feel the fire!” laughed the other. “You’re brave, all right, but you’re a fool, too!”

Case threw himself back on the deck and closed his eyes. Every instant he expected to hear Clay’s cries of anguish as the torture began. There seemed to be no help anywhere. Don was as helpless as himself.

All around the boat the night shut down, chill, silent, inscrutable. Far up the stream the lights of a small town shone indistinctly. To the west the peaks of Chimney mountain rose into the starlit sky. From the ocean, a long distance away, a light wind ruffled the water.

Everywhere was peace, and everywhere the great facts of Nature stood in friendly attitude to each other. It was only the human element that was warring! There seemed to be no hope of rescue anywhere!

Case blamed himself for sleeping while on watch. He blamed Captain Joe for not giving the alarm when these ruffians sneaked on board. But where was the dog? He had not seen him since his rude awakening. And where was Alex? He had not heard the boy’s voice in the cabin. He knew that Alex would be doing a lot of talking if present!

The boy knew that there were four men on board. He could hear a craft of some kind bumping against the side, and so he knew that they had followed the Rambler from Yuma by way of the river. He could not see the faces in the cabin, for the door was kept closed, but he could hear the preparations for torture going on!

He lay not far from the hatch which covered the motors when the boat was at anchor. If he could only get a little closer and run his hand down into the pit he might be able to switch off the electric current so the coils would not heat. He resolved to try.

Things were not going well in the cabin, for the boy heard the captors snarling and cursing at the coils. They did not seem to understand how to turn on the current, and so there was delay. Case pushed along to the hatch. As he did so his enemy released his hold for a moment and turned toward the cabin, saying as he did so:

“If you chumps don’t know how to run that stove come out here and guard this kid and I’ll do the work myself! It is easy enough!”

The fellow started for the cabin and one of the men inside turned toward the deck. For just an instant Case was free. He reached over to the hatch, lifted it so as to get his hand into the pit and turned off the electric current from the containers. In a second the boat was in darkness, and the pirates were groping about for their prisoners!

Case made a quick motion toward the railing, but was seized and drawn back. Clay and Don, who had succeeded in getting out of the cabin, were thrust back again. Still, the turning off of the current had resulted in delay, and that was something.

Clay called out to Case to know if he was still alive, and was given a courageous reply. Case’s guard bent over him with clenched fists.

“You turned off the electricity!” he shouted.

“Turn it on again, or I’ll spoil your face for you. Do it quick, too!”

There seemed to be no help for it. Case took all the time he could in lifting the hatch and turning the switch, but at last the lights flared up again, making the boat as light as day, for during the dark interval one of the men had turned the switch which fed the prow light.

While Case lay there, not daring to move hand or foot, his mind went back to Alex and the dog. Had they been killed at the first moment of invasion? Had they resisted and been thrown into the river?

“Come, now,” a voice in the cabin said, “you may as well tell us where the money is. We are bound to have it, you know!”

“I have told you the truth about the money?” Clay responded.

“Heat up the coils!” shouted the first speaker. “We’ll have to warm his feet for him! It is a cool night, anyway, and it may do him good.”

The boys listened for some sound of life on the river—for some trading boat to come creeping up! But there were no indications of the approach of any river craft whatever. Still, there was a slight jar!

Perhaps the Rambler had been struck by a floating log! Perhaps an eddy had sent the boat pulling harder against her chain! There was a slight movement on the aft deck. Perhaps the dog had been asleep there, or perhaps Teddy had returned to the Rambler and was creeping up out of the water The deck guard stepped to the prow to shut off the light.

Then a shot came from the rear, and the pirate threw up his hands, balanced unsteadily on the rail for an instant, and fell into the river like a stone. Case sprang out of the way as the fellow’s companions rushed from the cabin, brandishing their guns and demanding to know who had done the shooting.

Other shots came in quick succession, and another pirate dropped limply to the deck while the remaining two sprang over the railing and, not stopping to secure their small launch, struck out for the shore.

When Clay and Don came out of the cabin they found Alex and Captain Joe watching the two heads bobbing in the water. Case had arisen to his feet and was looking with all his eyes at Teddy, perched in a boxing attitude on the roof of the cabin.

There was little excitement in Alex’s face as he turned to Clay.

“I ought to shoot them both,” he said, pointing to the swimmers. “I know what they were about to do. Shall I shoot them?”

Clay shook his head and Alex put up his revolver.

“How did it happen?” the latter asked. “Who are those men?”

“They are river pirates,” Clay replied, “and I don’t know how it happened. Case was on guard, but the first thing I knew the men were in the cabin, holding a gun in my face. I guess Case must have been asleep.”

“I was,” Case said, sheepishly. “I ought to be shot!”

“He was asleep when I went away,” Alex, with a sly wink, contributed. “I ought to have got him up, but he looked too sleepy!”

“Where did you go?” demanded Case. “You’re a fine boy, not to make me get up and attend to business! And Captain Joe must have been sound asleep, too, or he would have given the alarm!”

“Captain Joe went to the beach with me,” the boy cut in. “We were just striking out for the mountain when we saw that something unusual was going on on board the Rambler. Then I saw Teddy swimming to shore and he told me what was doing! At least he insisted with his teeth on my returning right off. Guess we got back here just in time!”

“I guess you did!” Clay admitted. “The pirates were thinking of warming my feet! I almost wish you had killed them all!”

A motion on the deck caught the attention of the boys, and Clay went out to find the pirate who had fallen at the second shot trying to crawl to the railing. The boy did not interfere. The wounded man reached the railing at last and threw himself into the river.

“I don’t believe he is strong enough to swim ashore,” Clay said, “but we’ll leave that part to him. If he lives, he’ll be hanged some day, so he may as well drown now. Any man who will resort to physical torture to extort money has no claims whatever on humanity.”

“Now,” Don observed, with a quiet smile, “suppose we go on up the river? You boys were having trouble enough with me before this pack of pirates took the notion to steal my money from you. It seems to me that the only safe place for us is up in the Grand Canyon! I move that we get under way to-night and keep going as long as the river will permit.”

“That’s good advice,” Clay replied. “We’ll get as far away from this country as possible before daylight! This thing is getting on my own nerves! I’ve been looking for a quiet week or two, but I haven’t found them.”

The boys lost no time in getting the motors started. Then followed beautiful days on the river. The boys fished and slept and held boxing tournaments with Teddy, and sailed on under the sun and under the stars until the banks grew higher, the mountains closer to the river, and they knew that they must begin to take great care in navigating, for the Colorado river is not noted for its peaceful disposition!

One night they drew into a little creek running into the Colorado from the California side and built a roaring fire on the shore.

“Across the river,” Case said, pointing, “are the Blue Ridge mountains, and the summits you see are Mount Perkins and Mount Davis. Ten or fifteen miles up the river is Black Canyon, and thirty miles above the entrance to the canyon is Fortification Rock! There the Colorado turns to the east. Here our wild sport begins.”

CHAPTER XV.—TEDDY MEETS A RELATIVE.

“And right here is where we back up!”

It was one day later, and the Rambler lay in what looked to be a great lock, with gates out of sight! There were high walls on either side, and just ahead the view was shut off by an abrupt bend in the rocky formation. The Colorado river was pouring like a Niagara over a ledge where the narrow canyon turned.

“This Black Canyon thing does seem to tell us to go back!” Don remarked, with a sigh. “Looks like I’d have to leave you and take to the plateau in order to get to the Grand Canyon, after all. “This seems to be a locked door, all right! No boat can ever get above that tumble!”

“I’ve heard of boats going past Black Canyon,” Case insisted.

“They must have gone up in a balloon, then!” Alex suggested.

“There may be a passage around this series of falls,” Clay said.

“Well,” Alex sighed. “We’re out of sight of river pirates, anyway. We can see the blue sky over our heads, and that is about all!”

“Fine place to camp, on that shelf of rock!” Case put in. “I’d like to stay here a few days and investigate some of the caverns.”

“That’s a good idea,” Clay exclaimed. “And while we are looking in the odd crevices the water has made we may find some way of getting the Rambler up the river. Anyway, I’m not going to give up the trip until I have to! A man once went the whole length of the Grand Canyon in a boat! He must have got many a ducking!”

“Yes, but he was coming down, while we want to go up! If we were up above these falls, we might get down, by risking the boat and our own lives, but I don’t see how we are ever to get up!”

“There’s always a way!” laughed Alex. “I’ll get some of that drift out of the eddies and build a fire on that rock while you boys get supper. If you want fish, catch ’em. Seems to be plenty here.”

“You’ll have a fine time making that wet wood burn!” cried Case.

Alex pointed to an opening in the wall of the canyon, back of the rock.

“I’ve been looking into that nest,” he said, “and I’ve discovered that there’s dry wood and leaves in there. Some day when the Colorado was on the rampage, logs and limbs drifted in there and never got out again.”

“Why wouldn’t that be a good place to camp?” asked Don. “Aren’t you boys getting tired of sleeping in those narrow bunks every night?”

“You bet I am,” Alex answered, “and I’ll sleep in the cave if any one else will. It seems nice and dry in there, and Captain Joe can keep watch! Who’s in for it? Now, don’t all speak at once!”

“I am, for one!” Don explained. “I’ll just enjoy it.”

“The Rambler is good enough for me,” Case asserted, and Clay expressed the same opinion, so Alex and Don were the only ones to move their blankets and pillows into the cavern that night when they were ready to go to bed. Teddy went with them, but the dog crept back to the boat.

“Bears live in caves, anyway!” laughed Don. “I guess Teddy feels at home here, the way he is tumbling about. Cute cub, that!”

There was a fire, fast dying down, just outside the mouth of the cave where the two boys were, and they lay side by side in their blankets for a long time watching the flickering blaze and talking of the strange events which had brought them together. At length Don spoke of the papers.

“Do you really hope to find the third paper in the shack your uncle inhabited in the Grand Canyon?” asked Alex. “I ain’t so sure of it.”

“I am sure it is there,” Don answered, “but I can’t say whether we shall find it or not. I’ve been thinking that we might find the spot marked by an ‘X’ without it. I’m certain that the third paper tells only of surroundings—perhaps points the way to some bend or cliff. By looking over the locality very carefully, we may be able to find the sunburst and the big X. Don’t you think so?”

“Why, of course,” Alex replied, sleepily.

“Oh, if you're going to sleep,” laughed Don, “you’ll get no more of my wisdom! I'm sleepy myself, so here goes.”

But sleep did not come at once, for there was an interruption. Teddy arose from the blanket he had chosen as his bed and moved toward the entrance. The fire was low, now, and the boys could just see his figure outlined against a mass of red coals. He was growling.

“Come here, you foolish cub!” Alex called to him. “Don’t you go to starting anything here! We want to go to sleep. Understand, you cub!”

Teddy gave a low whine and moved back into the cave. Then the boys closed their eyes. But Don was restless and sat up in a few moments. Alex heard him, but kept his eyes closed. Then Don whispered in the boy’s ear and pulled at his shoulder.

“Alex!” he whispered. “Look out to the door and tell me if I am seeing double, will you? There’s Teddy outside again, but he is three times as large as he was a little while ago. Do you think there’s something in the atmosphere of this cave that induces growth in bears?”

“Aw, go to sleep!” was Alex’s response to the query.

“But that cub has grown to be about nine feet high!” Don went on. “He is as big, now, as one of the grizzlies at the Lincoln Park Zoo! Just wake up and see if you think we can get him on board the boat in the morning! If he continues to grow, he’ll be too big to get on a man of war by daylight! Come, wake up! This thing is getting on my nerves!”

Alex opened his eyes and looked, and the bear he saw was about as large as four Teddies all rolled into one. The great bulk of the animal almost closed the entrance! Alex sat up with a little cry of alarm.

“That isn’t Teddy,” he gasped. “That is a bear that wants to come to bed! I’d give a year off my life to be out of here right now!”

“Will he bite?” asked Don, innocently. “Teddy doesn’t bite!”

“Will he bite?” repeated Alex, and retreated to the end of the cave, for the big bear was entering, snuffing and growling, evidently angry because there were intruders in his bedchamber! Soon he began nosing at the blankets where the boys had lain.

The fire outside flared up and they saw Teddy advancing toward the larger animal. The cub was walking sidewise, turning his head from right to left, as playful puppies do when not quite certain of the character of the reception their advances are to meet with.

The big fellow looked critically at the cub. The boys were sure they could see an interrogation point in each eye! To them, at least, he seemed to be asking:

“Now, whose baby are you, and what right have you to come into my bachelor quarters, where babies are never allowed to come?”

Still sniffing the air, bruin rose on his rear feet as if to take the intruder into a crushing embrace. This was too much for the little cub who had been taught boxing lessons by three reckless boys.

He shot out of the obscurity of the interior of the cave, ambled up to the person of the house, and gave him a cracking box on the ear! The big bear went down under the impact of the blow, not having been prepared for it, and Teddy stood there ready for another round! There was added peril in every instant now, but, in spite of all, Alex snickered and Don broke into a ringing laugh.

“Go it, Teddy!” Alex cried. “Give him another! Hand him one on the bread basket!”

Just such words, just such advice, just such encouragement, had the cub often heard while facing one of his instructors! He knew no more now than to obey. Bruin received another wallop on the ear, but poor Teddy went down for the count, and the larger animal sprang at him!

It seemed for an instant as if the last days of the cub had come, but fortune favored him. Bruin hesitated for a moment whether to attack the cub he had floored or to take a bite out of the boys who had invaded his home. He chose the latter course and sprang for Don.

Now it began to look as if the boys would never get out of the cave alive. The bear was between them and the entrance, so they could not run away from him. Alex felt for his automatic, but remembered that he had left it on board the Rambler.

Don managed to elude the claws of the bear as the rush came, but all the time he was being crowded into a corner from which there would be no escape. He, too, reached for his automatic, but did not find it.

He found something quite as useful, however, as the result showed, in the form of an electric flashlight! As the bear advanced the boy opened the sliding switch and turned the round eye of light full into his face. Then he advanced, shouting wildly.

Bruin’s small eyes flinched under the strong flame. He threw up his nose, sniffed at the intangible thing which cut such a path of fire in his quarters, and began backing out. Don followed him, still shouting.

The bear stopped for an instant to give Teddy, now rising from the floor, a box on the ear and backed out of the cave. At that moment Clay and Case, who had heard the shouting, appeared on the deck of the motor boat with weapons in their hands.

“Shoot him!” Alex cried out to them. “Shoot the big stiff! He’s injured Teddy. Give him a couple of bullets!”

Both boys fired and the bear went down. Vital spots had been, in both cases, reached by the bullets, and the big fellow moved only in convulsive struggles after he dropped on the smooth rock in front of the cavern.

“It seems a pity!” Case said, standing over the fallen giant with his still smoking revolver in his hand. “The poor old chap had just as good a right to life as any of us. I’m sorry I shot him!”

“I guess you didn’t see him slamming Teddy around, and backing Don up into a corner!” Alex cried. “Only for the searchlight, there would have been a dead boy instead of a dead bear—perhaps two dead boys!”

“How is Teddy?” Clay called out.

“He’s getting on his feet again!” Alex replied. Then he broke into a laugh which echoed through the cave and out into the canyon and pointed to the cub bear.

“Just look at him now!” he cried. “He’s game! He wants to box the big fellow some more! Come here, Teddy!”

The cub dropped from his boxing position and approached the boy.

“Got knocked out, didn’t you?” Alex jeered. “Knocked plumb out!”

Teddy rubbed the sides of his face with his paws and snorted.

Alex and Don went back to the boat for the night. They had had quite enough of the cavern. In the morning, the first thing, the hide was stripped from the bear, rubbed faithfully with salt, and hung up to cure.

After breakfast Clay and Don climbed to the lip of the canyon and walked a long way to the north, the idea being to see if the river above the falls was suitable for navigation. They returned at noon and reported that if they could get over the falls they could run up for miles with little difficulty. There were rapids, but none the Rambler could not make headway against, they declared.

“And we discovered another thing,” Don exclaimed. “This rock we are on is an island! The river splits something about a mile above here.”

“Then where does the new channel come into the canyon again?” asked Case. “Perhaps we can follow up this new channel and so get around the falls. It is worth looking into, at any rate.”

“It must be down stream,” Clay suggested, “for we did not pass any junction. Perhaps we’d better drop down and find it.”

They found it half a mile below. The new channel was carrying a swift current, but the water was deep and there were no falls, so the boys got up full power and started up. The motor boat had the fight of her life, but she went up gallantly, sometimes hesitating, but always gaining in the end, until they came out above the falls.

“A few more like that,” Clay declared, wiping the sweat from his face, “and we’ll have to take the Rambler to the repair shop. That was a hard struggle for the old boat.”

From that time the voyage was not so strenuous, still, the going was rather more difficult than that encountered on the Columbia river trip. There were times when the boys were obliged to unload the boat and almost carry her, times when ropes were used to assist her up swift sweeps of water; but, then, there were wide valleys where Indians tilled small patches of earth, and where there were green things in view always. Whenever opportunity offered the boys procured water from springs in the hills, for the waters of the Colorado are full of the silt washed down from the mountains.

The Colorado river was born when the Rocky Mountains lifted their peaks above the continent. From their lofty heights the collected moisture flowed down on the plains below until a river was formed. From the base of the mountains to the ocean level there is a fall of a mile, so the river runs swiftly. The water cuts out the light soil and also heaps it up. In the canyons the river runs 6,000 feet below the level of the plateau, and people on the desert above might die with thirst because of the impossibility of getting down to the water.

The Colorado is forever changing its course and currents. Here mud flats are forming, there a bank is being washed away. Here a mighty rock topples into the stream, there the water cuts around a tower, leaving a pillar three hundred feet high, standing out alone! The river, ages ago, entered the Gulf of California where Yuma is now; in a few centuries it will fill up and make a level plain of the entire Gulf. It deposits silt enough in one year to cover sixty-six square miles of territory with sediment a foot deep! It is working hard to level the continent, ably assisted by the Columbia, the Mississippi, the Frazer, the Snake and the Gila!

The boys will never forget those days and nights on the Colorado. It was a golden time, and at last the Grand Canyon opened before them!

CHAPTER XVI.—CONCERNING A HEADLESS GHOST.

“Now,” Clay suggested, on the morning following the arrival at the mouth of the mightiest canyon on earth, “we may as well make up our minds that we can’t go very much farther in the Rambler. We will go in as far as we can, then tie up and investigate the great mystery.”

“If you want to see the Grand Canyon to good advantage,” Don advised, “get up on the plateau and look down and across. At the level of the river you see little save blue sky and rock, and you see those like one looking out of a well! Besides, it is pretty hot down here.

“There is little breeze, and we are a mile or more nearer the center of the earth than those at the lips of the cut. When it snows up above it rains down here. Clumps of willows which grow in the canyon look like fringes of grass from above. The houses where the guides and a few Indians live look like soap-boxes from the top.

“And, then, from the top, you can get the full contrast of the colors in the layers of rocks. You’ll see a wall of black granite rusty with the iron that is in it, and, a short distance away, you’ll see red, amber and green pinnacles with white tops. We’ll have to climb some to get to the shack where Uncle David lived, and so you may be able to satisfy your love of nature without going to the top.”

“Did any one ever sail down through this canyon?” asked Alex.

“Yes,” Don answered, “Major Powell succeeded in getting through with a boat, but some members of his party lost their lives. We can nose the Rambler up for quite a distance yet, but of course we can’t go through.”

“Then suppose we camp in the canyon itself to-night?” Alex questioned. “It will be fine to hear the waters singing!”

“We may safely do that,” Don answered. “We will, of course, be in what is known as the inner gorge, that is, away down to bed rock! We can get to within a couple of miles of the shack by night and make camp there. Then, in the morning, we can climb up and have a look at the old place.”

“You lived there for a time with your uncle?” asked Case.

“Yes, for a couple of years. But Uncle never made much of us boys. He seemed to want to be alone, and, besides, he often said that we ought to be out in the world learning to fight humans! Uncle had a notion that men and women were worse than wild animals!

“So, after a time, he sent us away, giving us tickets to Chicago by way of San Francisco and the S. P. While on the way back, as I have already told you, we visited the old house at Yuma. I never saw Uncle again. He was a strange old fellow. Where he got all his wealth is more than I know, but he certainly was rich.”

It was hard work sailing against the currents of the Colorado, but the motors were strong and reliable, and at night the boys found themselves shut in by towering walls of rock. Above, on either side, were shelves, ledges and precipices. Away at the top grew yellow pine and fir, below juniper thrived, and farther down were willows and various kinds of bushes. The light was dim long before sunset, and the river ran dark and sullen between the frowning walls.

“We’ve got to stop here,” Don declared, as the Rambler reached a point where the inner gorge widened out into a small valley—a very small valley indeed—“for the shelf where the shack stands can be reached only from this point.”

“How far up is it?” asked Clay.

“Something like two thousand feet.”

“Almost to the surface?”

“Not half way,” was the laughing reply. “There was a copper mine there, once, years ago, and the shack was left by the miners when the drive was deserted. It is an uncanny place!”

“How do you get there?” asked Alex. “Is it a hard climb?”

“Rather! In places the path is only thirty inches wide, with a wall a thousand feet up on one side and a drop of a thousand feet on the other! In places the way is so steep that steps have been cut in the rock, to prevent the burros slipping.”

“Burros!” echoed Alex. Walking up and down that wall!”

“Both burros and horses, after proper training,” Don answered.

“I think I'd rather walk!” Alex muttered, and Case nodded agreement.

“You’ll find that horses’ feet are surer than your own,” Don predicted. “There is rarely an accident here.”

The boys anchored the Rambler close to the shore, opposite the little spread-out of rocky soil and built a fire of driftwood. When night settled down the stars looked into the gulch bright and clear, and in time the moon arose and lighted the upper air, though its rays did not penetrate to the inner gorge at first, of course.

After supper the lads sat on the deck of the motor boat and watched the line of moonlight drop down on the west wall. Now it touched the top of a monument erosion had wrought, now it painted a shadowy wall where rocks were tottering to a fall.

“It is going to be a ghost night!” Don said, presently.

The other boys laughed at the expression, and Clay asked:

“Do they have ghost nights at the bottom of the canyon?”

“The ghost nights,” Don explained, gravely, “are found only near the broad level made by the dumpings of the old copper mine. Anybody who ever lived hereabouts can tell you that ghosts come forth at midnight and walk the ledges where they came to their deaths!”

“Bunk!” grunted Case. That’s all bunk!”

“About the ghosts? Of course, but there is something mysterious in the Grand Canyon! There are noises no one can account for, and sights which no one can explain are common. It is a haunted place!”

“I’m glad of that!” Alex exclaimed. “I’ve always wanted to form the acquaintance of a really, truly ghost! One may come to-night!”

“If one should,” laughed Clay, “you would be the first one to jump out of your skin with fright! I don’t want to be bothered with ghosts, for one, for I’m tired and sleepy. Besides, we have a hard climb before us for to-morrow.”

When the boys went to bed the west wall of the canyon was silvered with moonlight, while the east wall was still clothed in shadows. Case’s bunk was nearest to the door of the cabin, and Captain Joe, seeking companionship, snuggled down by it.

The last thing the boy heard, before he dropped into a sound sleep, was the uneasy breathing of the dog. After a time he awoke with a start. Captain Joe was bristling and growling.

“You ornery pup,” Case whispered, “keep still! You’ll wake the boys up! What do you see out there to growl at?”

Captain Joe advanced to the prow of the boat and pointed with a quivering nose to the east wall of the canyon. Then he looked back at Case and invited an apology for previous coarse treatment!

Case looked and turned back to awake the other boys, then changed his mind and stood waiting. On a descending shelf of rock five hundred feet above the level of the river, a white object could be seen creeping slowly downward. It was in the shadow at first, but presently came into a light reflected from the opposite wall.

Then the boys saw a white horse without a head and a white rider, also without a head! The horse moved slowly down the shelf toward the river, and the rider sat upright and stiff, not swaying at all with the motions of the horse! While Case looked the pair, the white horse and the white rider, came to an abrupt ending in the shelf.

To the amazement of the lad they did not stop there. They went on over the edge of the precipice and something white fell down, down, to a rocky bed below. As the white thing shot through the air a shriek of terror echoed over the canyon, and then all was still.

Case watched and listened with a wildly beating heart. The horse and rider had certainly gone down the precipice! He awoke Don and told him of what he had seen. Don looked serious.

“It is the ghost of the canyon,” he said. “For years, on moonlight nights, the horse and rider have gone over the precipice. It is said that a rider met death there years ago, and that his bones, and the bones of his horse, were found at the bottom of the precipice by a hunter. For a long time no one would come within sight of that shelf at night.”

“I don’t believe in ghosts!” Case asserted. “I don’t believe it was a ghost at all! It is some trick to drive us away!”

“But the sight has been seen for a long time—years before we ever thought of coming here,” urged Don.

“You don’t actually believe in it?” asked Case.

“There is something strange about it,” was all the boy would say.

“Will it ride again to-night?” asked Case. “If I thought it would I’d sit up and watch for it. I’m interested in this ghost.”

“It is never twice seen on the same night,” Don replied. “In fact it comes only when the moon reaches just such a position in the heavens. Always when the rider moves down the ledge you will see the shadow of that granite monument resting on the white boulder which nestles like a setting in that cliff.”

“Who compiled all the ignorance there is in the world regarding ghosts?” Case grinned. “I guess if people got a chance to return to earth after death, they wouldn’t be monkeying around in fool ways like that! This is some trick! You’ll see if we don’t get to the bottom of it before we go away! Headless horse, and headless rider! Why, even Captain Joe knew that they were not ghosts, for he woke me up growling at them!”

“Where is he now?” asked Don, looking around for the dog.

“He was here a minute ago,” Case replied. “He is not far away.”

“Don’t let the ghosts get him,” laughed Don, and went back to his bunk.

Case did not go to sleep. He was wondering if there really were people who actually believed in supernatural visitations! Reared in the hard school of the streets, he had long ago learned to accept nothing as true which did not comply with the standards of the knowable.

He wondered, too, where Captain Joe had taken himself off to. Usually the dog remained close to the boat at night, so his sudden disappearance was a puzzle to the boy. He whistled softly, but the dog did not come.

Then Case remembered the remarks Alex had made concerning the moonlight and the ghost nights. The lad certainly would be ripe for a visit to the bottom of the precipice. Case did not know what he might find there, but he had his suspicions as to what had gone down!

Alex kicked out vigorously and rubbed his eyes sleepily when Case shook him up in his bunk. He had no thought of getting up! Then Case whispered in his ear—whispered because he did not want the others to awake and learn that they were going away on a ghost hunt!

“The ghost walks!” Case rumbled in the boy’s ear!

“Leave mine in my pocket!” Alex yawned. “Where is he?”

“Not the money ghost,” Case snickered, “but the ghost that falls off mountains without being injured, and rides about the country with his head under his arm, or somewhere else out of sight. Get up!”

“Me for the ghost!” Alex exclaimed. “Bring him to me!”

“We’ve got to go and get him!” Case replied. “And you’d better keep still, or the whole bunch will want to go. Get up and dress.”

“I’m dressed,” replied the boy. “I was going out anyhow as soon as the others got to sleep. Where’s Captain Joe?”

“The ghost carried him off!” laughed Case. “Indeed he did,” he went on, as Alex expressed disapproval. “He hasn’t been seen since the headless ghost rode the headless horse down the bottomless precipice!”

“Wheels!” cried Alex, in derision. “You’ve got buzzing wheels!”

Case got the sleepy youngster out of the cabin and told him about the white rider and also about Don’s account of the tradition.

“Now,” he added, “I propose that we go down the shore a little way and climb up the slope to the foot of that precipice. You can see from here where the shelf ends. Well, anything dropped off the break would fall into a coulee on the other side of the ridge. See?”

“Perhaps we can get to the foot of the precipice, and perhaps we can not,” Alex said, “but we’ll try, anyway. What do you expect to find there? The dead ghost of a headless horse and rider?”

Case laughed and the two started away, following the river bank down until the rise to the east ran out, and then following the coulee back of it. In a very short time they were at the foot of the smooth wall of rock which dropped down from the shelf above. The moon was now far up in the sky, and its light fell directly into the canyon.

The lads looked carefully about the foot of the wall, but were not rewarded in any way for their labor. Presently, however, Case bent over a depression in the soil which had gathered in a corner—washed down from the heights above—and called to his chum.

“What do you make of it?” he asked, flashing his electric on the spot indicated. “Does that look like a ghost’s track?”

“Dog’s track!” Alex exclaimed. “Captain Joe’s track! Now what was he doing here? But here’s another footprint!” he went on, all excitement, “and it wasn’t made by a dog, either. Healthy ghost, that!”

“The ghost that made that track,” Case answered, “wore a No. 10 shoe with the taps worn down so as to show the nailheads! And the shoe was here not long ago, at that. Now, what was the dog doing with a stranger?”

“I reckon Captain Joe has been abducted!” grinned Alex. “I’d like to see the man that did it. He’d be some chewed up, I take it!”

“Well,” Case went on, “the dog has been captured, for here are the marks where he pulled back as he was dragged away! And I guess it was no ghost that did it, either. Just listen to that!”

CHAPTER XVII.—THE SUNBURST ON THE WALL.

The sound to which Case called attention was a long, quavering howl, such as a dog in captivity will sometimes make. It sounded far away.

“There’s the proof of it!” the boy said. “Captain Joe has been taken prisoner, and he’s trying to tell us about it. Now, how the Old Harry did any living person get him into a mess he couldn’t get out of?”

“What we want to know, just now,” said Alex, “is where he is, and not how he got there. The sound came from up above?” he asked.

“I thought so,” was the reply.

“Well, how are we going to get up there?” demanded the other.

The boys passed to the east of the precipice and came to a rugged incline which seemed to lead to the vicinity of the shelf of rock from which the ghostly visitors had apparently fallen. It was hard climbing for those unused to such exercise, but at last they stood on a summit which connected with the shelf farther along.

Below, five hundred feet or more, ran the Colorado river, its red waters hidden from the moonlight except in spots, for the outcropping walls make a view of the river from the top almost impossible. The boys could see the Rambler lying at anchor, however, and see the embers of the cooking fire not far away. There were no lights on board the boat when they first looked, but presently a glimmer was seen on the aft deck.

“What is it?” asked Case, mystified.

“Some one boarding the boat!” Alex cried. “The boys are asleep and Captain Joe is gone! Now do you see why the dog was abducted? We’ve got to get down there just as soon as we can. No knowing what may happen!”

“I guess we’re not going to lack for excitement!” Case mused. “We’ve got out of the path of commerce, but we seem to have struck a live wire, after all!”

“Shall we go back, or just wake the boys and go find the dog?” asked the other.

“If we don’t go back, we may not have any boat to go back to!” Case predicted. “The people down there are never prowling around for their health.”

“But the boys would be all right, awake, and I hate to leave the dog in bad company!” Alex protested.

“Say,” Case suggested, “suppose we take a couple of shots at the chaps who are monkeying with the Rambler? That will wake the boys!”

“That surely will wake the boys, anyway,” was the reply, and before Case could get his gun out Alex was peppering away at the air a few feet above the cabin of the motor boat.

The effect, below, was instantaneous. A light flashed out in the cabin, and then the prow lamp was turned on. Clay and Don could be seen scrambling out of the doorway, only half dressed.

There was no one else in sight. The intruder had made himself scarce at the instant the revolvers had been fired. It was evident that he had not visited the Rambler with the intention of attacking the boys.

“Hello, the boat!” yelled Alex, directly.

“Hello yourself!” came back in Don’s voice.

“What’s the shooting about?” demanded Clay.

“Take a run around the boat and see!” Case called back. “There is some one hiding near there! He can’t be very far away.”

“Why don’t you come on down?” asked Don. “Where are you?”

“Looking for the ghost!” Alex called out. “Come up and help.”

Finally Clay, who had made a quick circuit of the shore near the fire, reported that there were tracks of heavy shoes, such footgear as no one but a heavy man would be apt to wear, all around the remains of the fire! He asked the boys to return to the boat, but they advised a close watch and decided to continue their search for the dog.

“Because,” Alex reasoned, “they’ll take him farther away before morning, and, then, we want to see the ghost before he fades away at the coming of the dawn! The ghost with big feet!”

“He’ll fade away before the coming of the dawn if I get a shot at him,” grumbled Case. “He’s too free with our property!”

The boys heard the voice of the dog no more. Below they saw the motor boat blazing with light, the boys stealthily on guard in the cabin. Above, the moonlight flooded the lips of the canyon. To north and south the great river roared away, ever diving deeper into the bowels of the earth, as if to hide its red waters from the light of the sun.

From shelf to shelf, from coulee to coulee, from slope to slope! It was a weary night! Many times they thought they heard the dog calling to them. Once or twice they thought they heard voices. But always investigation of the localities from which the sounds had seemed to come brought no satisfactory result.

“Suppose we go back to the boat?” asked Alex.

Case threw himself down on a rock, yawned, and pointed to the western lip of the big canyon. It showed a tinge of pink.

“It is time, I think,” he said. “This light is not that of the moon, but of the sun! We’ve been all night blundering around here!”

But it was not possible to reach the boat in a few minutes. The lads were far up the east side of the canyon, and the path to the bottom was long, winding, and uncertain. They had wandered far to the north, too, and the location of the boat was hidden by a rocky summit.

Below them lay the level filling in front of the old copper mine. At the northern extremity of the fill stood a single shack, built of the boles of yellow pine and roofed with shingles rough-hewn from the same useful tree. Case pointed down and gave his chum a nudge in the ribs.

“Uncle David’s home!” he said. “The deserted shack!”

“Deserted!” echoed the other. “If it is deserted, tell me what the dickens the chimney is smoking for?”

What the boy said was true, for a thin column of smoke was ascending from the chimney of the old mine house, supposed to have been deserted by mankind long ago!

“Suppose we go down and make a social call?” suggested Case.

“It would be all right to find out who lives there,” Alex agreed.

“Probably some old hermit, like Don’s uncle,” Case ventured.

“Yes, probably; still, it may be the headless ghost! What do you make of that ghost business, anyway?” the boy added.

“I think it is easy enough to solve that puzzle,” Case replied. “Some man rode a horse down that shelf. Both were sheathed in white except their heads, which were wrapped in black. When they reached the end of the shelf the white garments, or blankets, or whatever they were, were tossed down the precipice. Then the black-clad horse and man went softly up the shelf again. There you have the solution according to Sherlock Holmes’ methods! Now, who is it that is playing ghost, and why is he doing it? That’s the question now.”

“But we went to the bottom of the precipice and found nothing white there. How do you account for that, wise one?”

“But we found footprints, didn’t we? That shows that there was some one there to-night, doesn’t it? And we found tracks showing that Captain Joe had been seized, muzzled, and dragged along, didn’t we? No ghost would do that! Circumstantial evidence is good in this case, but it wouldn’t convict the ghost of falling over the ledge or of stealing the dog, because, you see, there is proof that some other person had a chance to do these same things! Do you understand me?”

“All right, figure it out to suit yourself,” Alex agreed. “Perhaps you’ll be able, after a time, to reason out the purposes and personality of this false-alarm ghost, and to release the dog by induction!”

“I half believe you think there is a ghost here,” Case argued, half provoked at the mental attitude of the other. “Don’t you, now?”

“I certainly do not,” was the answer. “What I object to is your lofty, cocksure manner of accounting for everything. Here you go ahead and explain the events of the night as if you had seen every move made. But you may be right! Really, I half believe you are, and I’m sorry I didn’t beat you to it by figuring the thing out for myself!”

“Well, then, as we agree on the ghost matter, suppose we go down to the house and see who is there? Perhaps the occupant of the shack will invite us to eat! I’m hungry as a wolf, and then some.”

As the boys were about to descend to the level space in front of the old mine bore, Case caught Alex by the arm and pointed to the opposite wall of the canyon, some distance away. There was excitement in the boy’s tone and manner as he said:

“You remember the sunburst on the paper?”

“I should say so,” replied Alex. “I’ve got a copy of it right here with me. Why do you bring that mystery up now?”

“There’s a sunburst over there on the smooth wall!” Case said. “The sun shines on the rocks so as to produce the effect of one, anyway.”

“You’ve got to show me!” Alex exclaimed, with a provoking grin.

Case took out his watch and noted the time. Six o’clock.

Alex, puzzled, held the paper he had taken from a pocket out to his chum, asking:

“Six o’clock, you say? Now, look here! On this paper there is a figure six marked by the side of the drawing of the sunburst exactly at the point where the sun now strikes the sunburst on the wall. What does that mean?”

“Well,” Case answered, scratching his head, “there is a seven below the six. We’ll see if the seven stands in the same relation to the sunburst that the six does.”

“What do you mean by that?” asked Alex. “I don’t understand.”

“Look here! The figure six marks where the line of sunlight lies on the wall at six o’clock! That’s easy, isn’t it? Does the figure seven stand so as to show where the line of sunlight will lie on the wall at seven o’clock? Do you get that, muddlehead?”

“Well, what of it? I don’t see no sustenance in that?”

“Look at the other paper?” suggested Case. “Look at the big ‘X.’ That means ten o’clock, what? Suppose it means ten o’clock? Does that give you no idea? I guess you’re dense this morning, kid!”

“My head is so empty that it rattles, just as my stomach does!” Alex replied. “I don’t know a thing!”

“Well,” Case went on, “I’d like to be here at exactly ten o’clock and see where the line of sunlight lies on the wall then!”

“Oh,” cried Alex, “you think the papers point to time! When the line of sunlight reaches ten on the wall, as shown by the paper, a door will open and a troop of trained bankers will issue forth bearing chests of gold in their hands. Something like that, old chum? Do I get you at last?”

“No use trying to explain anything to you!” Case replied, turning away in a rage. “You’d better run back to the boat before you get lost.”

“Now, don’t get a grouch!” laughed Alex. “You know what I mean. When ten o’clock comes the line of sunlight will lie over the place where Don’s uncle hid something. Is that your idea?”

“Exactly!” was the reply. “Why didn’t you say that before, instead of giving out fool talk about trained bankers?”

“Then we’ve found the treasure!” Alex cried, eagerly.

“That depends,” answered Case. “We’ll come back here at ten this forenoon and see where the line is. There may be a cross on the wall there, or there may be a rock formation which resembles an ‘X.’ We’ll have to investigate. But wouldn’t it be fine if we could dig up this secret while Clay and Don were puzzling over it?”

“Indeed it would! But suppose we go down to the shack and see what kind of people live there. There may be something to eat in it!”

“If I had your appetite,” Case grumbled, “I’d go somewhere and run a restaurant! You’re either hungry or sleepy all the time!”

The lads laughed at the idea of Alex owning a restaurant, and scrambled down the slope to the level dump where the shack stood.

Smoke was still coming from the chimney. The windows had been covered with boards, securely nailed on, and the boys found the doors locked when they, after knocking, tried to enter. Circling around the shack, which was of good dimensions, they finally discovered a small door which was unfastened, and through this they entered.

They passed, with their electric lights on, through what must at one time have been a storeroom, came out in an old kitchen, passed on to a sitting room, which faced the front of the shack, and stopped to listen.

The smothered breathing of a dog came from an adjoining room, and they hastened to open the door. Captain Joe was tied up with a chain to a hook in the wall, the chain so short that he could not move more than a few inches. His head was covered with a heavy burlap bag, which was tied tightly around his neck.

When released and caressed, the dog appeared to be dazed, and the boys saw at once that he had been doped with some stupefying drug. This undoubtedly accounted for his being in captivity. In his usual health the dog would have made the tying of him up a difficult and dangerous proceeding. After a time Captain Joe lay down and rubbed the sides of his head with his paws, as if he had a very bad headache!

In the room where the dog was there was a bed, rumpled and dirty, and a couple of chairs. Under the bed was a pair of heavy boots, and Alex whispered to his chum as he looked at them.

“Big boots,” he said, “and the taps have been worn so that the nails protrude. Our ghost wore them, all right.”

Case went to a closet and began rummaging about. Presently he came out with a couple of milk-white sheets and a couple of black bags with eye and nose holes in them.

“We have either struck the home of a train robber or a ghost!” the boy said. “I’d like to know which!”

“You are likely to be informed soon,” Alex replied, “for there is some one coming in at the front door right now!”

CHAPTER XVIII.—CASE AND ALEX UNDER ARREST.

Clay and Don remained awake after the shooting. They kept the lights burning and waited anxiously for the return of Case and Alex, but they did not come.

While they waited Don told Clay the story of the headless horse and rider, expressing the opinion that the boys had gone out on a ghost hunt!

Clay was all interest in a moment, and indignant, too, because he had not been called in time to view the ghostly procession.

“That’s just what the boys have done!” he agreed. “They’ve gone off in search of that ghost! I’d like to be with them!”

“All the ghosts they find won’t fat them up any,” laughed Don.

“But they may solve the mystery!” Clay insisted. “That will be worth while, won’t it?”

“Of course! Now, I have an idea where they will bring up,” the lad went on, “and I suggest that we head them off as soon as it is daylight. The boat will be safe in the daytime, I think.”

“Where will they go?” asked Clay. “I’d like to surprise them.”

“If they follow along that shelf, after once getting to the top of it,” Don went on, “they will come out in time near the old mine, at the shack where Uncle David lived so long. They will go into the house and look for the ghost. Let us get there first!”

“All right! We’ll go just as soon as it gets light.”

But with the first glimpse of the summer sun came two husky men in a shell of a boat. They rowed up to the shore and stepped out close to the place where the Rambler was anchored. They were rough-looking fellows, with half-breed faces and cruel black eyes. The boys felt for their guns as they approached, although their movements were intended to be friendly.

“Hello!” one of the men shouted. “Hello, strangers!”

“Come aboard,” Clay said, thinking that he could do no less than invite the unwelcome guests to join in a cup of coffee, as the beverage was then bubbling on the electric coils at the back of the cabin.

The strangers re-entered their boat, pushed over to the Rambler, and mounted to the deck, their snaky eyes taking in every detail of the craft as they did so. Clay served them coffee and such food as had been prepared for breakfast, and waited for them to make their business known. At length one of them broached the subject.

“You’re Don Durand?” he asked, facing the boy.

“Yes; but how did you know that?” answered Don.

“I was about here when you lived with Dave.”

“I don’t remember you,” the boy said, suspiciously.

“I’m Flint,” reminded the other. “I worked in the mine for Dave.”

“I was a little chap, and didn’t know the miners,” Don hastened to say, for he was nervous under the evil eyes of the fellow who called himself Flint and claimed acquaintance.

“Uncle died after you left,” Flint continued, and Don nodded.

“You’ve come back to look up his property?”

Don hesitated, but decided to tell the exact truth.

“I came back to see the country, and if there is anything here that belongs to me I’ll take it away with me.”

“There’s nothing here,” Flint said, with a scowl. “A man named Frost came and took everything there was in the house.”

“And the papers?” asked Don. “Where are they?”

“He took them also. He hunted for a buried treasure until he got the whole county to laughing at him! I reckon Dave didn’t have any treasure to hide when he died! He was as poor as the rest of us.”

“I’m going to look through the old house,” Don said. “There may be something there this man Frost overlooked. By the way, I think I know this man Frost. But what right had he to come here and remove the property?”

“He had some kind of a writing, he said. I never saw it.”

“Do you know where he came from?” asked Don, then. “From Chicago?”

“He said he lived in Chicago,” was the evasive reply.

“Well,” Don concluded, “I’m going to tear the old house down, if it is necessary to do so to find the papers I want.”

“The old house belongs to me and Ike, here,” with a nod at his companion, “and we wouldn’t like to have it torn down.”

“Who gave it to you?” demanded the boy, angrily.

“I got it from this man Frost. He sold it to me. I let Ike in on a half interest, so, as I was sayin’, I wouldn’t like to have it torn down—not right away! In fact, I’ll shoot any person that even tries to get into it. Nothing personal, lad! I just speak generally.”

“Will you give me permission to look through it?” asked Don.

“I can’t see as it would do you any good to look through it. There is nothing there but dust and a few living things, such as dishes and the like. You wouldn’t care to see them, I take it.”

Don was about to make a hasty reply, but Clay seized him by the arm and drew him to one side. The boy was shaking with anger.

“Keep cool!” Clay warned. “We’ll get into that house, all right, but we’ll do it without permission from him.”

Flint and Ike went away while the two boys talked together. When they had disappeared down the river, the lads finished their breakfast and prepared for a visit to the old mine. It was nearly seven o’clock when they came within sight, from the south, of the building. They had been climbing for three hours or more.

At first they saw no one on the old dump, but before long they saw a heavy, flabby man in a broadcloth coat and silk hat working away at the front door of the house. Don’s voice shook as he said:

“That’s Josiah Trumbull! I guess he’s got me at last!”

“Looks more like you had him!” Clay retorted. “He seems to have a key to that door. I reckon he’s been here before.”

“A good many times!” Don replied. “Too many times!”

“I wonder if King is anywhere about?” asked Clay. “I don’t think Trumbull came here alone. I hope he’ll get kicked out of the house, if he gets in!”

Trumbull unlocked the door and swung it open. The house was in the shadow, for it was on the east side of the canyon, but there was a strong light across the great cut, where the morning sun was shining on the rocks. Trumbull stopped in the doorway, lighted a cigar, drew a long breath and turned to enter.

Then two quick shots came from the interior, and Trumbull crinkled up on the slice of stone which stood for a platform in front of the door. Thinking only of the tragedy which had taken place before their eyes, and not of themselves on their own safety, Clay and Don ran forward and bent over the fallen man. They saw in a moment that he was quite dead.

Then Case and Alex came rushing through the doorway, the latter carrying a smoking revolver in his right hand, his face white and pinched.

“Great God, lads!” Clay shouted. “Why did you do it? Why didn’t you wait? Why did you do it?”

Alex threw down the weapon and was about to make some reply when he was grabbed from behind. In an instant steel handcuffs were on his wrists as well as those of Case. There was no struggle. The boys were too dazed to resist and Clay and Don were too dumfounded to say a word.

Then, in another moment, King, Flint, and Ike appeared beside the body, bending over it, and Clay and the others dumbly realized that it was King who had manacled their chums.

“You’re caught with the goods!”

The man who had been called Ike was the speaker, and there was a note of triumph in his tone.

“You boys went too far this time. I’m sheriff here, and I saw the shootin’.”

“What does it mean?” asked Case. “Neither one of us did the shooting. Alex’s gun lay on a chair, and we missed it, and the next—”

“That will do for you!” broke in Ike. “Tell it to the judge.”

“Let him talk if he wants to,” King said, lifting his eyes bravely to the accusing ones of the boys. “He has a perfect right to make any statement he desires to make.”

“You’re a new one on me!” the man who had been called Ike said, with a scowl at King. “Who are you, and how did you get into the house? I saw you running, too, when the shots were fired.”

“I came here with Trumbull,” was the reply. “He went to the front door to get in, while I walked around to the rear to see what was going on there. I had noticed a window up when we approached.”

“How do we know that you didn’t do the shooting?” demanded Clay.

“The truth will come out in the end,” King said. “I was in there when the shots were fired, and so were these men. Who are they?” he asked, addressing his conversation to Clay.

“I’m the sheriff,” declared Ike, “and this man and me own the house. We seen the boys do the shootin’. Yes, we’ve got a clear case.”

He picked up the revolver Alex had thrown down.

“Is this yours, kid?” he asked.

“Yes,” was the dazed reply.

Ike whirled the cylinder, showing two empty cartridges. Then he put the weapon into his pocket with a grin.

“I guess that settles it,” he said. “We’ll take ’em to jail!”

“I never shot him!” Alex cried out. “I laid my gun down on a chair while I wrestled around with the dog, getting the bag off his head, and some one picked it up and fired! Next time I saw it, it was lying on the floor in front of the door to the side room, and I picked it up.”

“I saw you with it in your hand, a moment after Trumbull fell,” King said. “These men appeared in a moment, and must have seen you there, too.”

“Indeed we did,” Flint cut in.

“But you don’t believe he killed this man?” Clay appealed to King.

“It looks bad!” was the answer. “It looks bad, boys!”

“You’re prejudiced,” Clay said. “You’ve been sneaking around after us ever since we came on the river! You stole on board our boat, too, and tried to rob us. I believe you did the shooting yourself.”

Clay was angry and excited. His eyes flashed and his cheeks flamed as he accused King. The deputy made no direct reply, but stood looking at the revolver and at the prisoners.

“Well, we may as well take the boys to jail,” Ike suggested. “We’ve got a long climb to the top, and some distance to go after that.”

“If the people about here get wind of this cold-blooded murder,” Flint cut in, maliciously, “there may be a necktie party, so you’d better get them in a safe place as soon as possible.

He stared at Clay and Don as he spoke, and finally turned to the sheriff, who was moving closer to the boys, a triumphant look in his eyes.

“I think it might be well to take these two with the others,” he remarked, including Clay and Don with a swing of his long arm. “If I make it out right, this is a conspiracy-to-murder case, and these other lads are just as guilty as the others. Bring ’em along, Ike.”

Clay and Don sprang back as the sheriff approached to do the other’s bidding, but King interposed, preventing the advance of the other.

“Wait a minute!” he said, coolly. “Don’t move, boys,” as the two continued to retreat, evidently resolved to gain the boat. “This is my case, and these are my prisoners. I made the arrest, you must remember,” he continued, turning to Ike. “You can’t take them away from me!”

“Your prisoners!” shouted the sheriff. “We’ll see about that! Who are you? I’m the sheriff here! Keep away, or I’ll do something you won’t like! Keep away,” as King stepped forward.

King, perfectly calm, indeed, with a cynical smile on his face, took a long, folded document from a pocket and held it out to Ike. There was a moment’s pause, and then the other took the paper and glanced at it.

“You see,” King went on, with provoking composure, “that I am a deputy sheriff in this county, the same as you are. This commission gives me the same powers that you have, if you really are a deputy! Now, these are my prisoners, and when I require your help I’ll ask for it.”

The boys were still prisoners, but, somehow, Clay felt greatly relieved at the change in the situation. He regarded King as his enemy, but of two evils he considered him the least. Flint and Ike slunk back and stood glowering at the little group.

“I arrest the four for trespass!” Ike finally roared. “I’ll take them to jail for that, and you can’t stop me!”

“They are all my prisoners,” King insisted, “and I’m going to take them back to the boat. If you are an officer, you may summon the coroner and have him empanel a jury. And one of you would better remain with the body, without disturbing it in any way, until the coroner comes.”

“Are you really going to take us back to the Rambler?” asked Clay, his attitude toward King changing instantly. “You’re a squarer man than I thought!” he went on, “and I’ll withdraw all I said against you a minute ago! You won’t lose anything by giving Case and Alex a chance to show that they didn’t do the shooting!”

“No officer ever loses anything by being fair,” King said. “Now,” he went on, “I’m trusting to the honor of you boys, and I want you to do the right thing by me. I’m going to take off the irons and let the prisoners move about as they please, and—”

“If you do,” roared Ike, “I’ll have a man down here to watch ’em! I’ll have the boys out for a lynching! I’ll show you that no eastern sleuth can come here and run this county.”

“Will you remain here while this other man goes for the coroner?” asked King, paying no attention to the threats of the angry man.

“It is my duty,” answered the other, sullenly.

King unlocked the handcuffs and told the boys to wait while he entered the house. He was gone some minutes, and when he returned his face showed more excitement than the boys had ever before seen there.

“Come on, boys,” he exclaimed, without noticing the others, “we’ll get back to the Rambler. It has been some time since I have been aboard the good old craft.”

“I hope they’ll get away from you!” howled Ike.

“I’ll see that they don’t get out of the country if they do!” Flint cried out. “I’ll see that they get what’s coming to them!”

Without paying the slightest attention to the oaths and sneers of the two, King and the boys moved off down the incline, and, after hours of hard walking, came out on the bank where the Rambler lay.

“Now,” King said, as they all stood looking at each other with questioning eyes, “we’ve got as strange a murder case to handle as ever Holmes undertook to straighten out!

“It looks black for you two lads, but I’m going to see that you get a fair show!”

There was a smile on his face as he spoke!

CHAPTER XIX.—TWO GUESTS FROM CHICAGO.

“Why does it look worse for us than for the two men who were in the house with us?” asked Clay. “They had as fair a chance to do the shooting as we did, and they are none too good to shoot a man in the back!”

“But Alex’s gun is the one that did the work,” King explained, still smiling, “and he came out of the house, an instant after the man fell, with it, still smoking, in his hand! You’ll have to account for the gun getting away from him, and then back into his hand the next instant!”

“I can do that, all right,” Case hastened to say, motioning to Alex to keep still. “When we went into the house we found Captain Joe tied up in a sleeping room off the sitting room, at the front of the house. There was a heavy bag tied over the dog’s head, to keep him still, I suppose, and Alex laid his gun on a chair by the door of the sleeping room while he took the bag off.”

“Was the chair in the sitting room or the bedroom?” asked King, critically.

“It was in the sitting room, and Alex put it there because he rushed for the dog the instant we saw him in that plight, laying his gun, which he carried in his hand, on the first convenient thing he came to. It was dark in the house, with the windows all nailed up, and I was carrying an electric flashlight.”

“Where was the gun the next time you saw it, Alex?” asked King, gravely.

“It was on the floor, just outside the sleeping room door. I didn’t see it after I laid it on the chair until the shots had been fired. When I picked it up it was smoking. Some one grabbed it and fired, then threw it on the floor. It was done to get us into trouble!”

There was a short, gloomy silence, and then Clay asked:

“Mr. King, where were the men when you entered the house?”

“I did not see them when I first entered,” answered the deputy, with a quiet smile. “They were somewhere ahead of me.”

“When did you first see them?” questioned Don, in a moment.

“I was in the room back of the sitting room when the shots were fired and I naturally rushed forward, thinking that Trumbull had been foolish enough to do some shooting. When I passed through the rear door to the sitting room, the two men were in a back corner of the apartment, and Alex stood in front of the sleeping room with the smoking gun in his hand.”

“Did you hear any noise after the firing of the shots?”

“Several. Tell me the sort of noise you refer to.”

“A noise like the sliding of a metal substance across a bare floor.”

“You have the detective instinct, son,” King replied, with a grin. “Yes, I did hear a noise which might have been made by a gun sliding across a bare floor! But we’ll talk of that later. What I want to know now is what these men said to you boys this morning.”

“So you know of that, too?” asked Clay, in amazement.

Very briefly the boy then told of the morning interview, adding:

“They said they’d shoot any one who tried to enter the house.”

“But why are they guarding the house?” asked Case. “Why did they shoot Trumbull when he entered? They must have a notion that there is something of great value hidden there.”

“That’s the idea!” King agreed. “They think there’s a third paper somewhere in the shack! What do you think about it, boys?”

“Say!” Alex broke in. “We found the sunburst and the big ‘X’ this morning! If you’ll go at ten some day where we were at six, you’ll see something! We just happened to notice the wall, when we came to the top of a shelf, and there the things were!”

“And so you think you can find the treasure—if there is one hidden here—without the aid of the third paper?” asked the deputy.

“I can tell you better after I see where the sun-line touches the formation we called a sunburst at ten o’clock,” Alex answered.

“I’ll go with you to-morrow at ten o’clock,” King declared.

“I should think you’d be taking us to jail!” Alex grinned.

“You ought to be taken to jail for breaking into that house,” King laughed, “but if you’ll go get fish enough for us five and a couple of more fish-hungry people, I’ll let you remain at liberty a little longer!”

“If you think I’m going to catch fish for those big stiffs, you have another think coming!” Alex answered. “I’ll catch fish for you, but not for the others!”

“Other people came in here with me,” King went on. “They’ll be here directly, I think. There! That’s their knock, now!”

The “knock” was the sharp report of a pistol. King started away in the rowboat, leaving the boys gathered on the deck of the Rambler, all anxious to be moving, yet not caring to swim ashore.

Directly the officer came back around a bend in the wall of rock. In the boat was a man Don recognized on the instant.

“That’s Myron G. Frost, the manager of the bank where I worked!” he explained. “I guess he’s come out after me and the handbag!”

“Where do you think he came from?” asked Case. “How long has he been prowling around here? You don’t think he’s the ghost, do you?”

All these questions were asked at random, and to no one in particular, as King rowed the banker to the Rambler. Don moved back as Frost stepped on the deck, but the banker seized the boy by the hand and gave him a friendly little shake.

“You little runaway!” he cried. “I’ll keep track of you after this.”

“Where’s the use?” asked Don, dolefully. “I’m going to be put in jail for murder!”

“Poor Trumbull!” said Frost. “He was a crook, but he was trying to do the right thing when he was shot down! That was a brutal crime!”

“But you can’t lay it to me!” Alex declared. “I didn’t do it!”

The banker looked at King questioningly.

“Don’t they know?” he asked, and King smiled and shook his head.

“Flint did the shooting,” the banker said, then. “King and I came near seeing it done! We came to the door of the sitting room at the moment Flint was sliding the gun over the bare floor to the place where Alex found it. We, Trumbull, King, myself, and—well, one more!—came up here together last night and camped out not far from the old mine, with others! We saw you boys entering the shack, and King and myself followed on after you, while Trumbull went to the front door to head you off if you tried to run away from us.

“You see,” continued the banker, with a smile, “we did not know exactly what view you would take of our following you up here! I came near going to the front door, instead of Trumbull, but he had the key and thought it advisable to go that way in, himself. If I had, I presume I should have been shot, just as he was. My idea is that you boys would have been murdered, too, for the men who did the shooting are suspicious of any one who even looks at the old shack.”

“Why didn’t you tell us of this before?” asked Alex, turning to King. “You scared me out of a year’s growth. I don’t think I’ll ever get over it!”

“I arrested you for two reasons,” King replied. “One was to keep the murderers from doing it. The other was to prevent the murders discovering they were known to be the guilty ones. If I had done otherwise, there might have been more shooting, or there might have been a rush on their part to get away. I’m sorry if I frightened you, boys, but the scare didn’t last long!”

“The men may get a hunch, even now, and make off,” Case put in.

“You heard that shot, a few moments ago?” asked the deputy.

“Yes; of course we did—and thought some one was shooting for our benefit! What about it?”

“That was the signal that the men are under arrest.”

“But who did it? Say!” Alex blurted out “You make me weary! I’m all up in the air! Who arrested them? Where was this audience when we entered the house? How many of you came in here?”

“Trumbull, King, a couple of officers, and myself—and another!—came together,” the banker explained. King sent Flint off after the coroner in order to get the two apart. I have no doubt that each has confessed on the other before this. They are bad men when well backed up, but cowards when alone, I am told. Now, what about the third paper?” he added, with a sly smile. “Have you found it yet?”

“It is up there under the ‘X’ near the sunburst!” Alex insisted.

“There is supposed to be a glorious nest of ore under the sunburst,” the banker remarked, “but the third paper is in my possession! If Don hadn’t got out of Chicago so quickly, I should have told him about it, and also saved him a lot of trouble!”

“Trouble!” echoed Don. “Why, I’ve had the time of my life! But I don’t see what got you interested so suddenly, Mr. Frost,” he continued. “It was good of you to come out to us, but it must have been a great inconvenience to you. Why did you do it? Did King ask you to come?”

“There was a thin little lad came to the bank, one day, lately, and told me about an old house at Yuma, and what had happened there, and about King, and all the rest, so I wired King, and we met on the road. It was the lean little boy who brought me out here!”

“And it is the lean little boy who wants a fish dinner!” cried Tom, dashing out of a hiding-place in the rocks, above the Rambler, yet not so very far away. “Who’s going to catch those fish?”

“Tom, you rascal!” shouted Don. “Come down here and give an account of yourself!”

The lad was soon on board, and the subsequent ceremonies of reception caused King and the banker to shake their sides with laughter. The boy was pulled about and mussed over, and hugged until it seemed that there would be nothing left of him! Captain Joe and Teddy looked on in wonder.

“Now,” Clay remarked, when the physical reception was all over, “I’m going to catch some fish. You see that swirl down stream? Well, there’s a big one in there waiting for me. See me get him.”

Clay and Don took the rowboat and dropped down with the current. The river was fairly smooth where the Rambler lay, but farther down there were obstructions which threw the current over to the west, making a treacherous passage for a small boat. Those on the Rambler saw the boys drop down to the fishing ground, and then gave their attention to the work of the day, which they discussed gravely for a long time.

When Frost brought out his “third paper” it was discovered that it did not describe the actual means of getting into the mine which David Durand had discovered years before, or even what was in it! told of the bonds in the old house at Yuma, and mentioned the mine, but said that those who found it should receive the proceeds thereof!

So the location of the wonderful mine was as much of a mystery as ever, except that the boys believed they had come pretty close to it in discovering the formation which resembled a sunburst on the canyon wall! It was decided that the bonds and the $50,000 belonged to the Durand boys, the money having been taken from their uncle. The mine was to become the property of whoever found it!

“I’m going up to the summit to take a look at that wall again,” Alex declared. “I can’t get there by ten o’clock, but I can look it over!”

“And I’ll go with you!” Tom insisted. “I want to see the place where our fortune is.”

“Why not three?” asked the banker. “I want to get a look at the cliff now, as we may have to blow it down to find the ore!”

So the three went away, and Case and King set about getting ready for the return of Alex and Don with the fish. Some moments before the lads had slipped around an angle in the canyon, so they were not in sight.

“Suppose we drop down and see if they are there?” suggested Case.

So the Rambler was swung down around the angle. There a surprise awaited the occupants. The rowboat was there, far over on the west side, crushed and broken, washed up on a rocky shelf, but the boys were nowhere to be seen!

CHAPTER XX.—A JOURNEY IN THE DARK.

“I’ve a hunch,” Don said, as the boys rowed off after fish, “that we would better land on the east shore, at the point where others have beached the boats, and try our luck fishing off the bank. That current looks ugly to me!”

Clay, who was rowing in order to give steerage way, rested a moment and looked over his shoulder at the water, sweeping toward the west shore with resistless force. The Colorado river, in passing through the Grand Canyon, makes many sharp turns in drift because of great rocks which have tumbled down from the cliffs, and so block the flow, turning it aside in angry swirls. It was one of these eccentricities the boys faced.

“There’s where I want to fish!” Clay explained, bending to the oars again. “Keep her over to the west, and we’ll get a big one in that deep pit next to the shore. If we ease along with the current, we won’t tip over. Don’t let the current strike her on the side!”

But the current did strike the boat on the side, struck her like a shot and whirled her round and round. One oar was twisted out of Clay’s hand, and Don lost the paddle he was steering with.

“Hang to the boat!” shouted Clay, and Don clung like death to an oarlock as the boat went over, half filled, righted, and swung toward the west shore. Striking a rock near the shore, she turned turtle, but the boys held on, and were dashed out of water where the current beat against a narrow beach which lay between the shoreline and the cliff.

Clay scrambled up, limping, and Don made his way farther up holding his right arm with his left hand. The former caught the boat as the wash moved it toward the current and drew it up on the shore, a dilapidated-looking craft, with the prow on one side crushed in!

“We are having great luck with rowboats!” Clay said, viewing the craft whimsically. “We ought to buy ’em by the dozen!”

“The boat be hanged!” Don grunted, rubbing his elbow, “what we need is a dozen lives! Say, but that was a dump!”

“Cheer up!” grinned Clay. “All we’ve got to do now is to swim a mile or so across the stream and get back to the Rambler! We’re stranded on a desert coast, with nothing to eat and nothing to catch fish with!”

“Perhaps we can follow the shore up and attract the attention of the boys,” Don suggested. “I can’t swim across!”

“I don’t believe the Rambler can get over to this shore,” Clay said, looking over the mass of broken waters. “There’s more than a million big rocks in there. You know, we kept off this shore when we came up.”

“Well we can walk up and see what the chances are,” Don grunted.

But the lads did not walk up very far before they came to a cliff which stood out flush with the water, and against which the current thundered with a sound like the booming of heavy artillery. To the west the canyon wall rose sheer a thousand feet.

“Right here is where we get ours,” Don exclaimed. “A fly couldn’t climb up that wall! We’ll have to wait here until the boys look us up.”

“It won’t take them long to find the broken boat!” Clay mourned.

“And they’ll want to know about the fish for dinner!” Don finished, with a grin.

The cliff which blocked the narrow beach set out from the main wall of the canyon like the leg of the letter “L,” and the lads sat down in the angle to dry their clothes in the hot sunshine. In a moment Clay sprang to his feet and began running up and down the beach.

“That’s the first symptom!” Don grinned. “You’ll be fit for the foolish house in an hour or two. Go on and play you’re an aeroplane and lift us both out of this!”

“Where does this cold wind come from?” asked Clay, paying no attention to the facetious remarks of his chum. “There’s an open passage in the west wall here! Can’t you feel the current of air?”

“I certainly can,” Don answered. “Perhaps it comes from above!”

“No, sir! It is right down here in this angle—the opening, I mean! And it is a strong current of air, too, so it must come from some canyon to the west. The rocks are piled in here in all kinds of shape, anyway. When the Colorado bored down, it upset things and left lots of layers standing on end. Here! See that little opening? Well, there she blows! Little bit of a hole for so much wind.”

“Just like a campaign orator!” Don commented.

Clay looked at his friend reproachfully and crowded into the aperture, which was formed by two layers of rock, stacked up on end, as he had before expressed it, much farther apart at the bottom than at the top. The passage was about four feet in width, and not much more than that in height. The bottom was covered with a fine sand, laying in wrinkles, and showing the action of running water.

“You see,” Clay observed, pointing down, “this is a water channel at certain seasons of the year, so it must lead to some open place.”

“You’re never going in there!” shouted Don. “How do you know what kind of wild animals you’ll run against?”

“Of course I’m going in,” Clay replied. “For all we know, this hole leads to a parallel canyon which we can ascend to the vicinity of the motor boat. If we had our searchlights it would be a picnic.”

But their searchlights were on board the Rambler, and so it was anything but a picnic the boys had following the dark passage. The walls brushed their elbows at times, and occasionally they ran their heads full tilt against the roof of the cavern, but the floor, being at times the bottom of a torrent, was comparatively level, except that it mounted up at an angle of about twenty-five degrees.

The atmosphere was remarkably pure, for the cool wind which had attracted Clay’s attention to the opening, continued to sweep through the passage, but it was dark—wretchedly, miserably, uncannily dark, and the boys imagined many times that they heard the warning growls of wild animals or felt the touch of slimy reptiles. Twice they came to places where their progress seemed blocked, but these were only twists in the rock, and directly they found their way on again.

Presently, at his very feet, Clay heard the rush of water, and halted. The boys stood together for a time and listened. It was falling and not running water they heard. Somewhere in the interior of the mysterious passage, there was a waterfall.

“If we only had a light!” wailed Don. “We’re likely to break our necks or get drowned if we go on without one.”

“You just wait a second!” Clay announced, gleefully. “I’ve got a few matches in a water-tight case! Why didn’t I think of them before? I’ve carried them with me ever since we left Chicago, and never found use for them until now. Now, suppose I’ve lost the case!”

There was a moment of suspense, and then the boy’s searching hand came upon the smooth metal of the match case. There was a chance that the matches would be worthless, because of the long time they had been kept, but the boy opened the case and struck one.

A blue flame sprang up, sizzled, wound around the pine stick, and went out. It was clear that no match flame could live in that breeze unless better protected. Clay opened his wet coat and struck another. This one, protected by the coat and the body of the boy, flamed up.

Then, with the stick burning brightly, Clay pushed it ahead, shielding it with his hands as much as possible. At his feet he saw a current of water disappearing into a hole in the bottom of the passage. Beyond that point they would be obliged to wade!

“This accounts for the passage being dry below,” Clay said. “And it indicates that there’s a passage under this one. The old cliff is honey-combed with water-bores, I guess!”

The traveling was more difficult now, but the boys kept on, sloshing through water up to their ankles. At last they saw a speck of light some distance ahead, and gradually the passage widened out. The water, however, grew deeper under their feet as they advanced toward the light.

“This is a blooming river, that’s what it is!” Don shouted. “If we had a line we might catch fish in it!”

“I’ll be swimming in a minute!” Clay called back. “I’m up to my waist now! And the current is strong enough to lift me off my feet.”

The pitch of the passage was now greater than before, and the water the lads were wading in came down with a rush. When they got to the entrance they were obliged to cling to the wall to avoid being carried back into the subterranean passage.

When the boys came to the full light of day, they saw the sun shining on a pool of clear, glistening water, which lay in a cup-like depression in a narrow canyon sloping up to the north. Judging from the time they had been in the passage, Clay concluded that they were at least six hundred feet from the river, and not far from two hundred feet above it.

The canyon in which they found themselves was little better than a deep wrinkle in the massive formation of the west shore, but it seemed to point the way to an exit up stream. After wading the pool, which was supplied by springs in the walls, they gained a dry bottom and proceeded northward, still climbing.

“If this crack in the earth keeps on this way for a mile or two,” Clay suggested, “we will come out on the wide shelf that divides the west wall not far south of the old mine. From there we can signal to the boys who went up there, and they can come in the motor boat and get us. We never can swim across. In the first place, it is too far; and in the second, the current is too strong.”

“You heard the story Case and Alex told about the sunburst on the wall?” asked Don.

“I thought that rather fishy!” Clay replied.

“We’ll soon have a chance to find out whether it is or not,” Don continued, “for we’ll come out on the shelf near the place they described—if we come out on the river bank at all.”

“But we’d be too close to the sunburst and the ‘X’ to see them,” Clay remarked. “You have to look at such large things from a distance in order to discern them at all.”

“If we can get there some day by ten o’clock,” Don hastened to say, “we can mark where the line of sunlight lies, and that will help some. But,” he added, with a frown, “I guess we’re not going to get out to the river wall by following this old scratch in the earth! Here’s where it turns to the west! Now, what about it?”

“It may bring us to the top, anyway!” Clay said, encouragingly.

But it did not bring them to the top, for directly it ran into a cavern not unlike that which the boys had passed through! Disgusted and disheartened, the lads took to the tunnel and pressed on in the darkness. The only satisfaction they felt was that they were still going up.

“If this pitch keeps on,” Don declared, “we’ll come out at the very top before long!”

“We’re not far from some top now,” Clay replied, “for it is getting lighter in here, and the light comes from the roof!”

But this was true for only a short distance. It soon became dark in the passage again. After a time, still ascending, the passage turned to the east, narrowed, and then the boys heard the rush of the river.

“We’re getting there!” Don shouted. “Look out there!” as he peered out of the hole. “There’s the river, and there’s the old mine, and there’s the shelf of rock above which they saw the sunburst!”

“That’s all right,” grumbled Clay, “but if we drop out of this hole we’ll fall into the river. The door to this blooming cave doesn’t open out on the shelf! And it isn’t a very big door at that!”

“I’ll bet we’re in the mine!” cried Don.

“No wonder it was never found, then, if people had to reach it the way we did!” Clay exclaimed. “Say!” he went on, in a moment, “let me get to that opening again. I wonder if we can’t climb up out of it! I’ve seen such places! The shelf seems to be only a few feet away, and we may be able to gain it if we can creep on a wall like flies!”

“I can!” Don laughed. “Let me get out and show you!”

But Clay was half out of the narrow entrance, clinging to points of rock with his fingers, digging his toes into crevices which were too shallow for much of a hold.

“Can you make it?” Don called out, anxious and afraid for his chum.

“Sure I can! Wait until I get up on the shelf and I’ll help you out of the passage! And, say, there’s the mine dump away up to the north, and some one on it! I believe it is Alex and Tom. Yes, and there’s the banker! They are looking through field glasses!”

“Give me a hand!” cried Don. “I want to be in this procession myself. Look there,” the boy added, as he stepped up on the shelf of rock, “they are motioning to us to stand aside! Do you know what that means? It means that we are standing on the line between them and the sunburst or the big ‘X.’ I reckon we’ve just come out of the mine!”

“Hello!” came a call from across the great chasm.

Clay put his hands to his mouth and called back:

“Hello yourself! We’ve found the mine!”

“Where’s your fish?” shouted Tom. “Where’s the f-i-s-h!”

“Fill your pockets with gold and jump over!” Alex shouted.

“Send the boat after us!” Don called back.

Alex made a trumpet of his hands and shouted back:

“I’ve just been up on the cliff looking for the Rambler. She’s gone! There’s no sign of her anywhere. Where’s the little boat?”

“Busted!” Clay called back. “Wrecked! smashed!”

“Then you’ll have to swim!” Alex decided. “And you’ll have to be quick about it, for there’s a lot of natives climbing up on that shelf who don’t look very good to me.”

CHAPTER XXI.—THE CLUE IN THE ROCKS.

Clay looked quickly about, but there was no one in sight. Alex, from the old mine dump, pointed downward, so the boy knew that the natives referred to were near the river and working upward.

“If they get up by that route they’ll be doing something,” Don remarked. “Never heard of any one doing it.”

“Well, there are people coming up, just the same,” Clay went on.

“Then they’re coming up to look up the mine!” Don declared. “There’s probably been a lot of talk about the mine lately, and the people of the county are all stirred up over it!”

“They haven’t got anything on us,” Clay grinned. “We saw it first!”

“You’re right about that, but here’s the bunch coming! Hear their voices? Suppose we duck out of sight? Can we get back into the mine?”

“I can,” replied Clay, and in a minute the shelf where the boys had stood was empty.

In five minutes’ time, however, half a dozen roughly dressed men were talking in front of the opening from which the lads looked out; that is, as near in front of it as they could get without standing on air!

“I say there was some one up here!” a harsh voice insisted. “The people over there were shouting across to him.”

“Where is he, then?” asked another voice.

“I don’t know! I half believe some of those confounded boys have found the mine opening and hidden it in!”

“I guess they can’t find it if we can’t,” came another voice.

“But Flint said it was somewhere off this shelf.”

“If he knew where it was, why didn’t he find it?”

And so the talk went on, while the men searched every foot of the shelf and the wall back of the shelf. It was clear that Flint, after being arrested for the murder of Trumbull, had tried to buy his liberty by proclaiming a discovery of the famous Durand mine!

“We don’t have to discover it to-day,” was finally said. “We can come back at any time and locate it.”

“But what about those boys? Old Dave Durand left a paper, so I’m told, saying that whoever found this mine might have it. Now, if these boys find it, what good does that do us?”

“Well, keep right on looking if you want to!” was the surly answer. “I’ve had enough of climbing to-day. Besides, those people on the old mine dump are watching us. We wouldn’t dare enter the mine if we should find it—not with them looking on!”

“I wish we had our searchlights,” Clay remarked, as soon as the others had disappeared. “We may be in the mine and we may not be! I don’t believe there is any gold or silver here, anyway! If there was gold here, there would be outcroppings in other places close by.”

“That is the way it strikes me,” Don returned. “If there is anything of value in here, I reckon Uncle David put it here. If you knew what a queer old fellow he was, you would think so, too.”

“What would he have to hide here? He secreted the bonds in the old house at Yuma, and it seems to me that if he had possessed other things of great worth he would have put them with the bonds.”

“There is no knowing how much money the old fellow had,” Don continued. “He made a million or more in Chicago real estate, and at the time of his death, I am told, there wasn’t a cent of his money in any of the Chicago banks. He was afraid of banks. I guess that Mr. Frost was the only banker he ever trusted, and he trusted him with his nephews and not with his money! Oh, yes,” the boy went on, with a sigh, “the poor old man sent word to Frost to look after Tom and I! So Frost says. I never knew that Uncle cared enough about us to do even that!”

“What would he naturally leave in a place like this?” asked Clay.

“Bonds or money—money, probably.”

“I’ve got a few matches left,” Clay insisted, “and I’m going to use them to see what sort of a place this is. If there is any money here we ought to be getting it out.”

“Yes; before the natives come back,”

Clay lit a match and looked about. Where he stood there was merely a long passage, high and roomy at the back but narrowing down to the small opening the boys had used in front. There were no openings in the walls, no places where anything might have been stored away.

“Now, go on in farther before you light another,” Don suggested. “He may have made a hiding-place of the next angle.”

The flame of the match revealed a shallow niche in the north wall. In the niche lay a metal box the size of a sardine box. It was covered with rust, and did not open readily when Clay drew at the cover.

It came open after a time, however, and both boys bent over it.

“This isn’t a treasure!” Don exclaimed. “This is a clue! A sure enough clue in the rocks! And only paper!”

Clay put the box, closed, into a pocket and moved toward the entrance. Don followed on behind, gloomily enough. He had expected so much of the discovery they had made, and a tin box had been the only product of it!

“Just our luck!” he complained, as the two stumbled along.

“Never you mind!” Clay said. “How do you know what this box contains? It is only a paper, but even a paper may tell where a million is hidden! Wait until we get out into the sunshine, and we’ll see what it says. Your Uncle David certainly was an odd one! The idea of any one in his right mind hiding a paper in a dreary place like that!”

At last the boys reached the ledge again. Mr. Frost, Alex and Tom were still on the level dump in front of the old mine. They motioned to Clay and Don as they came out, indicating that they were going away to look for the Rambler. Clay held up the box, drew the paper out, and held that up, too. There was excitement across the great chasm!

Alex seemed to be pointing the way down, and Banker Frost was motioning to Clay to be careful of the box and the paper.

“If those natives got down from here, we can!” Don exclaimed. “We can go anywhere they can! How we are going to get across the river is what gets me! Can you swim it?”

“I’m not going to take the risk,” was the reply. “They will have to come after us in the Rambler.”

“But the Rambler has disappeared,” Don reminded the other.

“I don’t believe anything serious has happened to her!” Clay insisted. “Case and King ought to be able to take good care of her.”

Just as the boy finished speaking the clamor of the motors of the Rambler was heard. King and Case had picked up the broken rowboat and started up toward the old anchorage.

But the motor boat did not stop at the landing. Instead, she ran up toward the old mine. It was pretty risky, but the Rambler was staunch and true to her helm, and finally passed the perilous places and lay in reasonably quiet water opposite the mine. Under ordinary circumstances King would not have countenanced such an undertaking, but both were anxious over the fate of the boys who had gone off in the small boat, and they were anxious to confer with Frost and the others on the subject.

The three on the dump, after a long and difficult downward climb, reached the water’s edge and managed to get on board without getting wet, as the river was deep and still at the end of the dump, and the motor boat ran up close to the bank.

They had scarcely begun telling the story of the missing boys when Alex pointed to Clay and Don, crawling down the opposite wall like flies.

“How did they ever get there?” asked King, amazement in his face.

“We’ll never know until they tell us!” laughed Alex. “Can’t you run the boat over and get them?”

Here was another risk, but finally, by running far up stream and coming down on the west side and tossing out a long rope, Clay and Don, wet but triumphant, were hauled on board. Clay with the precious metal box containing the paper wrapped up in his coat and held as much out of the river as possible.

When the box was opened and the paper spread out, it was found to hold only a map of the old shack by the mine. Under the location of the window in the sitting room where Trumbull had been shot to death, the paper showed a black mark—a great cross, evidently made to imitate the rocky formation above the cave where the paper had been discovered.

“So it wasn’t a treasure you found in the mine,” laughed Frost, looking at the map, “it was only a clue!”

Clay insisted that the boat be put back to the mine landing, and again they all made the long climb to the old house. There was no mark of any description under the window designated by the map, but Alex found a hatchet and went at the ceiling with which the room was lined.

In a moment he came to a metal surface off which the hatchet slipped.

“Work around it! Dig it out! It is a treasure chest!”

Don laughed as he spoke, for, to tell the truth, he had no idea that anything more of great value would be found. His idea was that the bonds already found had constituted the greater part of his uncle’s wealth.

Directly a steel box which weighed at least fifty pounds was brought out. The cover was on tight, and there was no key. In fact, it did not seem possible to get the box open without having it cut with tools secured for that special purpose.

Frost looked at the box closely and smiled as he noted how neatly the lock was concealed—even the keyhole, if one there was, being out of sight. The box was carried aboard the Rambler, with great difficulty, and then a start for the old landing was made.

The surprise of the day was when the mysterious box was opened!

CHAPTER XXII.—THE END OF A LONG JOURNEY.

It was growing dusk when the motor boat reached its old anchorage. The hungry lads set themselves at work getting supper at once, and Alex and Case volunteered to bring in fish! Clay and Don had made such a mess of their fishing expedition that the boys roared when a fish supper was mentioned.

“If we didn’t get fish,” Clay replied to their taunts, “we got something more valuable! I guess that iron box is worth more than a fish!”

“I don’t see as it is,” Tom grunted. “No one can get it open!”

“There ain’t no place to open it!” Alex complained. “I believe it is just a solid block of metal. It is heavy enough to be that!”

Case and Alex went ashore and followed down the bank, dropping lines into deep pools until they were out of sight of the Rambler. In the meantime Frost and King stood regarding the iron box. Indeed, there seemed to be no way of opening it. While they contemplated the puzzle a hail from shore was heard, and directly a man sprang aboard, the Rambler having been drawn close to the bank because of the loss of the rowboat.

“This is the sheriff,” King explained, as the boys regarded the newcomer with suspicion. “I presume he has news of Flint and Ike.”

“They confessed about as soon as they were placed under arrest,” the sheriff began, “and each one lays all the blame on the other. It seems that they knew from David Durand himself that articles of value would be left for his nephews to find, and ever since his death they have been looking for the treasure. They believed it to be a mine.”

“And they have been living in the old house?” asked Don.

“Yes, most of the time.”

“Then they weren’t far from something that was hidden,” the boy declared. “This box was secreted in the wall.”

“What is in it?” asked the officer.

“We don’t know. We can’t open it!” was the discouraged reply.

“But there must be a key somewhere,” the sheriff said.

“There isn’t even a keyhole,” Don grinned. “It’s shut tight!”

“Well,” the officer went on, “Flint and Ike have confessed, and they will be hanged. That is what I came here to tell you. The body of the dead man will be buried near the old mine, if that is satisfactory to you all,” he continued. “He was a crook, too, wasn’t he?” he added.

“For years he was,” the banker replied, “but at last he came to his senses and offered to help me in restoring the dead man’s fortune to his nephews. He employed King—the man you made a deputy at my request—to assist in finding the boys, after Don took the handbag and got away. He came out here to help solve the mystery of the mine. He had the third paper at one time, but returned it to me.”

“David Durand found strange hiding-places for his money!” the sheriff mused. “Think of the bonds in the old house, and this box in the cave. I have been thinking of the queer old chap ever since Mr. King told me about him. It is a wonder the bonds were ever found—and the old wallet! What a place for property!”

“There’s a letter somewhere which explains everything!” Don insisted.

“It wasn’t in the wallet, was it?” asked King. Don shook his head, and Clay brought out the wallet to prove it.

“Here’s some banknotes,” he said. “They will have to be sent in for redemption, they’re so rotten, and this thin piece of steel. That’s all there is in here. Look and see for yourselves.”

While they were examining the wallet and the half-rotten banknotes. Clay stood with the key in his hand, looking at it thoughtfully. In a moment he walked over to the iron box and began an inspection of that. He felt over every part of the surface several times before his fingers came to a little perturbance.

Then, in a moment he had the key pushed into a slit of a hole which had been brought to view by the removal of a small plug-like piece of metal which had been set into the body of the box. He moved the key this way and that for a moment, and then there came a sharp click. The top of the box, working on rusty springs, flew back, revealing a mass of papers, with a sealed envelope lying on top.

They all gathered around while Don, to whom the letter was addressed, opened the message from his dead uncle. The writing was very brief. It said:

“If you find this the bonds belong to you and Tom. There are more bonds in the strong room at the old house in Yuma. I have given you all the trouble I could think of, my boy, before delivering my property into your hands. I don’t think it good for boys to get money easily. If this box is never found until the bonds have rotted, then so much of the government debt will have been paid. If you should ever get locked in the Yuma treasure room, the key to the iron door is in the wall-safe with the bonds. From your cranky uncle.”

“That is all!” Don said, slowly. “And we might have gotten out of that cellar if we had only looked closer into the wall-safe!”

“A strange old man!” mused the banker. “He never provided for Don and Tom, personally, yet he interested me in them. He trusted Trumbull instead of me—unless Trumbull stole the two papers which were in the handbag with the money!”

“He did steal them!” King declared. “Don knew he had stolen them, for his uncle had, in a measure, told him about them. When Trumbull mentioned papers revealing the location of a mine in the Grand Canyon, Don knew of course. I presume, however, that David thought Don would have the two papers, so he gave me the third one, which Trumbull stole and afterwards returned!”

“It has been a great muddle!” Clay laughed, “and we came along with the Rambler just in time to get mixed up in it.”

“Look in the packages,” the banker advised, “and see how much of a fortune you have. The letter speaks of bonds.”

There were in the iron chest government bonds to five times the value of those found in the treasure room at Yuma, so Don and Tom were very wealthy boys.

“We are always finding wealth for others!” laughed Clay, “but none for ourselves! However, we are planning to take a trip down the Mississippi next, and we may have better luck there! But here come the boys with plenty of fish, and we’ll have supper right away!”

And such a supper as they had! All the precious dainties the lads had been hoarding for some such event were brought out, and there was feasting until a late hour. Captain Joe and Teddy had their full share of the good things, and the dog was forgiven for permitting himself to be doped by Flint! If he could have talked he would have explained that the drug was eaten in a very fine piece of meat, and would have added that he would never more take food from a strange hand!

“By the way,” the sheriff said, as he arose to go, “with the arrest of Flint and Ike the ghost of the Grand Canyon is laid! They have been playing ghost a long time to keep people away from the supposed mine.”

Then Alex explained how he had found the white wrappings they had worn, and also the black head coverings, in the closet at the old shack.

“And now, can we get up any farther?” asked Clay, as the lads were preparing for sleep. “Is this the end of navigation for us?”

“You can’t have any fun in going on,” Don declared. “It would be a great task to get the motor boat up farther.”

“Then we’ll turn back,” Clay decided, “and see if we can find as much excitement in the down trip as we did in the up trip!”

“I don’t see how you can!” Don laughed. “You won’t have the two trouble makers with you, for Tom and I have decided to go back to Chicago with Mr. Frost, and meet you there later.”

“If you boys don’t mind,” King said, “I’d like to go down the Colorado with you. I’m in need of just such a loafing spell.”

The permission was given, and the next morning, after Frost, Don, and Tom had climbed to the plateau and started away to the nearest railroad station, the Rambler was gotten under way, and the down trip begun.

It was a glorious river trip. The desert shone and glistened in the sun, the mountains laughed from under their white caps, the river sang its everlasting song of peace and quiet!

The boys took a month to reach Yuma. There the Rambler was placed on board a platform car and started on its journey eastward. It was the plan to ship the motor boat to as near the head waters of the Mississippi as possible and sail down that mighty stream in the early fall.

An account of this exciting trip will be found in the next volume of this series, entitled:

“The Motor Boat Boys on the Mississippi; or, the Trail to the Gulf!”