of the Moslem faith. They were known as valiant and deadly fighting men. The pagans were primitive people, like the Bagobos.

"Davao is a large, fairly modern city. But once outside of the city itself, the country becomes wild. Some of the Bagobo villages are quite close to Davao. They are peaceful folk, and quite harmless, but there are savages in the back country who may not be."

"Perhaps we should take arms," Zircon said.

"I would say so. At least a rifle and a sidearm of some kind."

Scotty spoke up. "I can take my rifle."

"And I can borrow Hartson's forty-five automatic," Zircon added. "That should be enough."

"True," the colonel agreed. "You can always call on the constabulary for help. I will give you letters to all commanding officers in the area."

Rick knew that would open many doors, because Rojas was not only a former commandant of the constabulary, but popular with the entire force.

"How about clothing, Colonel?" Rick asked.

"I assume you will go by air. That means very little baggage. One tropical suit and the rest rough clothing would be my suggestion."

Scotty changed the subject. "Sir, have you any idea what might have happened to our friends?"

The officer shrugged. "No more than you have. Scientists generally are not rich enough to rob, but they are not so poor that they can be harmed with impunity. Robbery is always possible, although unlikely, with one exception. Did they have any weapons with them?"

"Shannon had a hunting bow and arrows," Mr. Brant replied. "He planned to collect some specimens. Briotti had no weapon at all."

"Then that eliminates the only robbery possibility I can think of. Had they been well armed, Moros might have attacked to get their weapons. The Moro loves weapons of all kinds, and may even kill to get them—a point you might remember."

Rick shook his head. "It's hard to imagine why anyone would want to harm them—if anyone did. I think we'd better get to Mindanao as soon as possible. When do we leave, Dad?"

"Tomorrow night, son. I made reservations for you while I was in New York this morning."

"Are we going to take special equipment?" Scotty asked.

Rick had been thinking about that very point. "I'm planning to take the Megabuck network. It will be useful if we have to separate."

The little network of three miniature radio units, transmitters, and receivers combined, had been of invaluable help in rounding up a group of foreign agents bent on stealing the plans for a United States intercontinental ballistic missile.

The unusual name, Megabuck, had grown out of a joke Rick had conceived about a "million bucks" television quiz program. Two of the sets were pocket size, and used hearing-aid-type earphones. The third had been made in the form of an ornamental hair band for Rick's sister Barby to wear. The tiny microphone worked by sound induction through the bones of the head. The earphone was incorporated into one end of the band.

Zircon and Scotty agreed that the radio units might come in handy, and the physicist added, "I have a pocket-size, battery-operated wire recorder I use for making notes. I think I'll take that. It may be helpful for recording conversations for later translation."

"A good idea," the colonel approved. "The local dialect is called Chebucano. Of course many people speak some English. Have you an atlas? I think it might be useful if we went over a map of Mindanao and the Sulu Sea area."

The map study was very helpful. The three absorbed Colonel Rojas' fund of information about the area. It was a part of the world none of them had ever seen, located only a few degrees above the Equator in the deep tropics. To the west of Mindanao was the Sulu Sea, with the Celebes Sea to the south. The widely scattered centers of civilization had famous, imagination-stirring names, like Jolo, Tawi Tawi, Cotabato, and Zamboanga.

Later, the Filipino officer dictated letters of introduction to Rick's sister Barby, a pretty blond girl a year younger than her brother. Barby took the dictation directly on the typewriter. Once the letters were signed and turned over to Dr. Zircon, Hartson Brant escorted the colonel to the mainland, where arrangements had been made for a local taxi service to drive him back to New York. Rojas' parting statement was "This affair worries me. I shall be most interested in developments, and you may hear from me sooner than you think."

Later, Scotty and Rick gathered in the latter's room and talked while loading the radio units with fresh batteries.

"Wonder how long it will take to hear from Chahda?" Rick asked.

"Depends on where he is and how fast Steve Ames can get a message to him. He'll join us if he can. You can bet on it."

"I hope so," Rick said thoughtfully. "We'll be in Manila in a couple of days, and we'll need him. We've got a job ahead of us, because Tony and Shannon aren't lost. You can be sure of that. They're not the kind to get lost. And if they had been in an accident of some kind we'd have heard."

"Meaning what?"

Rick's eyes met Scotty's. "That leaves only one logical answer, doesn't it? They've either been killed or captured!"

CHAPTER II

The Hindu Merchant

Thirty-six hours later, after a grueling transcontinental—trans-Pacific flight with only the briefest of stops to change planes, Rick, Scotty, and Zircon were in Manila. Their stay in Manila only three hours old, they had already visited the American consulate and found that no new information on the missing scientists had been received; they had arranged a luncheon date with Dr. Okola, and had reserved space on Philippine Airlines to Davao on the following morning.

Rick paced the floor, sipping a glass of fresh limeade, made with calamansi, the tiny, pungent local limes. His time for the past three days had been spent alternately dozing and thinking about the problem of the missing scientists. The more he wondered about their strange disappearance, the more worried he became.

"There's simply no reason for it," he said aloud.

Scotty looked up from the chair in which he was reading the Manila Times. The husky ex-Marine didn't have to be told what his pal was thinking. "No reason we can see," he agreed. "But there has to be a reason."

Hobart Zircon spoke from the desk where he was writing a note to Hartson Brant. "You might remember, Rick, that we've been on other expeditions where the reason for certain events was just as puzzling."

Rick knew the kind of events the physicist meant. Only a few dozen yards from this very room, in the ancient walled city across the street, he and Scotty had been under rifle fire for a reason they couldn't have guessed at the time.

"Listen to this," Scotty said suddenly. He read from the newspaper. "'The American consulate reported today that three members of the Spindrift Foundation staff have arrived in Manila to begin a search for the American scientists reported missing a short time ago. The scientists disappeared north of Davao.' End of item."

"That's short and to the point," Rick commented a little bitterly. "They certainly don't make much fuss over two missing Americans, do they?"

"And it's on page seventeen," Scotty added. He folded the paper back to the front page. "Look at this headline."

Across the top of the front page was emblazoned: WHERE IS ELPIDIO TORRES?

"Who's he?" Rick asked.

"A Filipino kid. He ran away, got lost, or got kidnaped. No one knows which. His father is a big sugar operator and politician. The kid has been gone for weeks, but the paper is still playing it up at the top of page one."

Rick snorted. "Headlines for one Filipino boy and page seventeen for two American scientists. Some contrast!"

Hobart Zircon fixed a stamp to his letter and walked over to the boys. "You're not thinking straight, Rick. Suppose two Filipino scientists were lost in