CHAPTER I
Followed by Rascals

“THE Sahara Desert! Adventure! Exploration!” breathed Joe Lewis, as he sat with four companions on the deck of the steamer Sylvania, awaiting their first glimpse of North Africa.

“It’ll be wonderful!” muttered Bob Holton, who was also deeply touched. He, like his chum, had often pictured this mission into the heart of the vast expanse of sand. Soon it would be the real thing. Already the youth could feel his feet plod through the loose soil, could sense the delight of long traveling in a little-known land.

Dr. Kirshner, a noted archæologist, looked up from the book he was reading. His bronzed face took on a wide smile as he scrutinized the two young men.

“Got the old spirit, all right,” he said with twinkling eyes. “I suppose it came from that expedition in Brazil. Every explorer gets it sooner or later.”

“That’s right,” agreed Mr. Lewis, Joe’s father. “They say the main characteristic of a true explorer is his ability to sense the thrill of adventure.”

“Then we’re real explorers. Isn’t that right, Dad?” grinned Bob.

“‘We’?” asked Mr. Holton, trying to appear serious. “Where do you get that ‘we’ stuff? You and Joe have only bothered us on one expedition. We men have faced the scorching sun scores of times, and should by now have caught the true meaning of it all. But you boys – ”

“Wait a minute,” cut in Bob, determined not to be beaten so easily. “Where would you have been if it hadn’t been for Joe and me? It was our ingenuity that brought about the success of the expedition.”

“Well, I must say I hadn’t thought of that before,” laughed Mr. Holton.

“It’s true, all right.” Bob stoutly defended himself and his chum. “If you say the word I’ll prove it.”

Mr. Holton smiled. He took a great delight in arguing in a friendly manner with his son, although at times he was forced to admit defeat. This time he was satisfied to drop the matter and turn his eyes to the western sky, where the sun, a great ball of red fire, was sliding into the bluish waters of the Mediterranean. Gradually the ball faded from view, leaving a soft blue sky, which a moment later became streaked with long gold streamers. At last these became molded into one great mass of color and light, crossed and dotted with every hue of the rainbow. Slowly the spectacle faded from view, and the sky became a warm blue, out of which came countless glittering stars.

It was a wonderful sight, and although the adventurers had witnessed it several times before, they never seemed to tire of it. Bob and Joe especially were deeply stirred.

“Now that we’ve seen our last sunset on this voyage, suppose we get our belongings together,” said Mr. Holton, getting up from his chair. “It won’t be long until we reach Algiers.”

“And if what we’ve heard is true, it’s a wonderful city,” added Mr. Lewis. “Has the most unusual blend of things Arab and European on the globe. Monuments, mosques, palaces, everything and more that characterizes the spirit of North Africa.”

He arose and led the way up the deck to the cabin, where already people were gathering to await the first sight of land. Among the passengers were brightly garbed Egyptians, Algerians, Arabs, and many others with quaint and picturesque costumes. Everyone was in a gay mood, laughing and talking merrily. That is, all but two tall Arabs, whose quiet gaze was fixed on Bob, Joe, and the others of the American expedition. That the men intended mischief was sensed by the boys, although their elders had caught no element of danger.

“Wonder what they want?” murmured Bob, in an undertone to his chum. “Fact is, I’ve noticed them before, but never said anything about it. They seem to follow us, for some reason or other.”

Joe nodded.

“I’ve thought the same thing,” he said quietly. “But as they made no move against us, I almost forgot about it till now.”

The youths said no more until they reached their stateroom, which was directly across the hall from that of their elders. As soon as their belongings were together, Bob decided to mention the matter to his father and friends.

“Ten to one they haven’t noticed these men,” he said to Joe, “and it might be best for us to put ’em wise.”

The youths found their companions preparing to leave for the deck and motioned for them to come in the room. Then Bob told of the actions of the two Arabs, pointing out that they probably had no good intentions.

The men listened closely, eager to get all the details. When the boys were finished, Mr. Lewis looked grave.

“They probably heard Dr. Kirshner mention the hidden treasure,” he said soberly, at the same time glancing about as if he expected to see the Arabs at the door.

“Hidden treasure? What treasure?” demanded Joe excitedly, while Bob looked up in surprise.

“It may only be a yarn,” replied Dr. Kirshner. “In fact I just heard about it this morning. An intelligent Arab with whom I made friends pointed out that he had definite information that there were great riches amassed in a cave in the heart of the Sahara Desert. It seems that they had been placed there by native tribesmen, or Tuaregs, who inhabited this region hundreds of years ago. Tuaregs even today are very fond of raiding caravans and small towns. Got it in their blood, I guess.” He paused a moment for breath, and Bob seized upon the opportunity.

“But why did the Arab tell you this?” he asked. “Didn’t he know – ”

“I know what you’re thinking,” the scientist interrupted. “You’re wondering why I got in on this. I did too at the start. But as soon as he had finished with the details, he told me that he was not equal to making the expedition alone and had no relatives or good friends to accompany him. He went on to say that few expeditions are sent out into those remote regions, and that he would gladly share the treasure with us if we would go with him.

“Now as this treasure cave is supposedly in the region that we intended to explore, your dads and I could see no reason for not taking him up. His services as a guide will also be invaluable.”

“But – but how does he know where to search?” questioned Joe Lewis, his tone indicating that he was greatly puzzled.

“He has a map,” returned the archæologist. “Got it from an old tribesman who was about to die. Whether or not it is accurate, we have yet to see – if nothing prevents us,” he added significantly.

“Nothing will – if we can help it,” said Bob, delighted at such an opportunity.

A few minutes later they lugged their possessions out on deck. And they were none too soon, for it was scarcely ten minutes later that the lights of land became visible – dimly, of course, but they were there.

“At last,” sighed Mr. Holton, who, although he enjoyed the long voyage, was anxious to reach his destination.

Although land was a great distance away, the adventurers went to the prow to catch a first glimpse of that mysterious country on which they would soon set foot.

Bob and Joe watched closely as the myriad of lights grew more plain. A stronger beam flashed from the Cape Matifou lighthouse, and numerous lights from ships in and about the harbor were also visible. No more could be seen. But it was enough. Bob and Joe were convinced that Algiers was a charming city indeed.

“How large a place is it?” asked Joe, as the Sylvania neared the port.

“About two hundred and fifty thousand,” returned Mr. Holton. “And all different races, from Americans to Turks and Jews. Oh, we’ll see sights all right.”

Gradually the boat pulled into the harbor, reversed her engines, and stopped at a large dock. Then among lights the gangplank was lowered, and the boys and their elders soon found themselves among the many hurrying passengers. Lights were everywhere, almost as numerous as in an American city, and they had no trouble in finding their way to a hotel.

“Oh, by the way,” exclaimed Joe with a sudden recollection, “what became of your friend the Arab – the one who knows about the hidden treasure?”

“He’s at another hotel,” replied Dr. Kirshner. “I have his address on paper. We’ll go over there in the morning. He had already made reservations at this hostelry or would have put up with us.”

The remainder of that evening was spent quietly, for the explorers were tired after the long journey on the Sylvania.

Bob and Joe were up early the next morning, and after a small but satisfying breakfast they started out for a short walk. But they had scarcely covered a square when Joe, who had happened to glance back, stopped suddenly and nudged his friend.

Bob looked, and an answering expression of surprise and anger came on his face.

Walking slowly into the hotel were the two Arabs who had acted so suspiciously on the ship.

CHAPTER II
Scoundrels at Work

“WHAT do you suppose they want?” asked Joe, as the youths followed the movements of the Arabs.

“They’re not there for any good,” returned Bob, a look of anger, and at the same time anxiety, on his face. “Probably want to find that map that tells of the hidden treasure. Oh, of course it could be a coincidence that they picked the same hotel that we did, but it isn’t likely.”

The boys watched the suspicious characters until they disappeared into the hotel. Then Joe suggested that they cautiously follow.

“All right,” Bob agreed. “But we must be careful and not get too close. They might have guns and think nothing of using them, and they could probably get away in this country.”

Slowly the youths moved up to the entrance and peeped around the corner. Satisfied that there was no one in sight, they went inside.

“Nobody here but our dads and Dr. Kirshner,” observed Bob, glancing about. “I wonder if they noticed the Arabs?”

“Let’s ask them.”

The men had noticed the fellows, they said, but thought nothing about it. Why? Was anything wrong?

Bob explained that they were the two who had acted in a suspicious manner on the ship, and at once the scientists’ faces lightened.

“Come on,” urged Dr. Kirshner. “We can’t get there any too rapidly. When they find that we haven’t got the map, they’ll probably help themselves to money and anything else that happens to be lying about. They may even search other rooms.”

Hastily, and yet quietly, the boys and their elders went up the stairway. They were unarmed, their revolvers and other firearms having been left in their rooms. This might prove a handicap if the Arabs possessed weapons, but the Americans thought nothing of the risk they were taking.

“We’re five to two, even if we haven’t our guns,” said Bob, clinching his fists. “They’re likely to be shaken by numbers.”

But Dr. Kirshner, who knew the ways of these cunning natives, smiled grimly.

In a short time they reached the floor on which were their rooms and turned cautiously down the hall. With utmost care lest they be discovered, the explorers tiptoed up to their rooms.

Mr. Holton took the lead and glanced around the door into the room. A moment later his face scowled.

“What is it?” demanded Joe, in a whisper. “Are they inside?”

Mr. Holton shook his head.

“Worse than that,” he said solemnly. “Take a look.”

While the others are taking in the situation, it might be well to tell something about Bob Holton and Joe Lewis and, incidentally, their fathers.

Bob was a big, well-built youth of some eighteen years. He was particularly fond of adventure and life in the open, and always welcomed an opportunity that might bring about a realization of his desire.

Joe, who was about the same age, was of medium size and strength, with a naturally dark complexion that was now still further darkened by the tropical sun. He, like his friend, was fond of adventure, hunting and fishing and hiking whenever the opportunity presented itself.

The youths were together much of their time and agreed on practically every point. Their home was in Washington, D. C., where their fathers, Mr. Holton and Mr. Lewis, were employed as naturalists by a large museum.

A short time before, the youths were successful in persuading their fathers to take them on an expedition to unexplored Brazil. Here they helped the naturalists shoot and classify wild animals, birds, and reptiles and had many thrilling adventures with wild animals and savage Indians. How they fought hand-to-hand with a huge jaguar, barely prevented themselves from being crushed by a terrible anaconda, battled against rapids, and finally became lost and wandered for days in the world’s greatest jungle are told in the first volume of this series, entitled, Lost in the Wilds of Brazil.

The boys spent the following winter finishing up in high school, and scarcely was graduation over when their fathers were requested by the museum to make an expedition to the Sahara Desert to collect specimens of any animal life that might be present in the remote interior. Dr. Kirshner, of whom something has been said, wished to accompany the naturalists to investigate the remains of ancient civilizations. At once Bob and Joe requested that they be taken also, and after careful consideration their elders at last consented. What the boys were particularly looking forward to was taking motion pictures of the desert, for they had been engaged by the Neuman Film Corporation to get many unusual scenes.

Less than a week later the expedition sailed on the steamer Sylvania and made the long voyage without any special incident.

Now let us return to the boys, as they advanced into their elders’ room.

At once their mood changed, an expression of astonishment, later turning to anger, creeping over their faces.

Everything in the room was in the wildest disorder. Clothes, shoes, satchels, rifles, papers lay scattered about, the scene suggesting that a cyclone had visited the place. It was most deplorable, and the travelers stood for some time as if trying to catch the true meaning of it all.

Finally their anxiety caused them to move forward and inspect the belongings.

“Good thing we didn’t have the treasure map,” remarked Mr. Lewis, examining the contents of a small black bag. “It wouldn’t be here now.”

At the end of their inspection the explorers found that nothing had been taken from their belongings. It appeared that the crafty Arabs wished only the treasure map, and that, not being able to find it, they had left without any other spoils.

“They sure acted in wild haste,” observed Mr. Holton. “It’s almost impossible to see how all this could have been torn up so quickly. It wasn’t five minutes from the time that you boys told of seeing the men that we were up here.”

“Trust the Arabs to do that,” said Dr. Kirshner, with a dry smile.

The scientists’ possessions were placed back in their proper places, and then they went to inspect the room occupied by Bob and Joe.

“Probably nothing taken from here, either,” was the opinion expressed by Mr. Holton, and he proved right, as they later found.

“This shows that these Arabs are desperate characters, and will probably stop at nothing,” said Dr. Kirshner, after a moment of thought. “We must be extremely careful to lock everything up from now on. It may even mean that we’ll have to watch ourselves, too.”

“What do you mean?” asked Joe.

“Simply that they may try to kidnap one or all of us to get possession of the map,” he replied in a low voice. “I know these natives. I’ve seen some of their actions before and feel sure that if these two men thought there was a good chance to get the map, they would try to do it.”

“It may not be as easy as they think,” said Bob, although he was a bit uneasy.

No more time was spent in the rooms, for they were all desirous of seeing more of the strange city and country.

“It might be wise to call on our Arabian friend first,” said Dr. Kirshner. “The one who knows about the treasure, I mean. We haven’t seen him since we left the ship last night, and he may be anxious to know what plans we have in mind.”

“Yes,” agreed Joe. “And while there we can warn him against these crooks. They may come on to him for the map, since they found that we haven’t it.”

First, however, the boys’ fathers and Dr. Kirshner wished to breakfast.

“And while they’re busy eating, suppose we go out,” suggested Joe. “We don’t need to stay but a few minutes.”

Bob agreed. He, like his friend, was anxious to observe the strangeness of this unusual city. If what he had heard was true, it would be something to be long remembered.

Out on the street the youths were at once impressed by the wide variety of races and costumes. Frenchmen, Italians, Spaniards, Mahonese, and Maltese all walked side by side, the majority in European garb. Arabs, or rather those who are commonly called Arabs, for they are a very mixed breed, sauntered along, clad in their long gowns and hlafa, which hung down over the face and sides of the head. Occasionally a Negro could be seen, although this was the exception rather than the rule.

“Sure have variety here,” smiled Joe. “There’s about every race imaginable present.”

In a short time the youths reached the Place du Gouvernement, or central square, and the busy scene of life was very interesting. On one side of the forum was the Mosque of Djema-el-Djedid and the Grand Mosquée, and on the others were stores, hotels, and cafés. Stretching away in the distance were the four great streets of the city.

Bob and Joe spent some time in one position, watching the throng of Arabs, soldiers, Jews, and others peculiar to this metropolis. Strange, the boys thought, that the people paid little or no attention to them. But this was probably due to the fact that hundreds of tourists visit the city each year.

“I’d like to visit some of the stores,” remarked Bob. “But we’d better get back to the hotel.”

“Yes. Our dads and Dr. Kirshner will probably be waiting for us.”

Reluctantly they made their way back and found that the scientists were ready to leave for the Arab friend’s hotel.

“We’ll trust that we’ll find him in his room, or in the lobby,” said Mr. Holton, as he and the others followed Dr. Kirshner.

“He’ll probably be there,” returned the archæologist. “He’s expecting us over this morning to talk over the best procedure to find the hidden treasure.”

The hotel in which the Arab was staying was but a short distance up the street and around the corner. The explorers were barely within sight of the building when a figure rushed madly out of the door and came toward them.

“Something the matter with that fellow?” asked Bob, surprised to see such haste from the native.

“Looks that way,” returned Mr. Holton. “He’s – By George! It’s our Arab friend. Wonder what has happened?”

A moment later the man was up to them, his face white, his hands trembling.

“The treasure map!” he cried in poor English. “It is gone!”