The two boys left behind in the tent stared perplexedly at each other in the light of the lantern hanging from the pole and casting a steady if not brilliant illumination over the canvas walls, bed rolls, packs and camp chairs. From his bed roll or bag, as the boys adopting the term of African explorers had come to call it, the outstretched Bob, on one elbow, looked toward the tent flap which had fallen behind his comrade and said:  
“Gosh, Frank went out of there as if somebody had grabbed him by the hair. Wonder what he’s up to.”
 
“I’ll go see,” said , getting up from his seat on a folding camp chair, and walking toward the exit.
 
But just as he was putting out his hand to draw the flap aside there came the sound of three revolver shots in rapid succession from nearby, followed by a of native cries. Jack leaped through the exit, drawing his automatic from its ever-ready position at his side, while Bob jumped to his feet with all thought of weakness forgotten.
 
Before he could follow Jack’s example, however, the tent flap was again thrust aside and Jack returned followed by Frank.
 
The latter’s face was white. In one hand he still gripped his automatic.
 
Bob stared at his comrades in too great for a moment for speech. And in the silence the yells of the natives could be heard withdrawing into the distance.
 
Frank flung himself into a camp chair. His revolver dropped from his relaxed fingers, and he put up his hands to his face. Bob saw he was trembling. Jack stooped and put an arm across his comrade’s shoulders.
 
“What in the world’s the matter?” cried Bob, finding his tongue at last. “What happened?”
 
“I haven’t got it straightened out,” said Jack, shaking his head. “It was all over when I got outside. Give Frank a minute’s time to collect himself. He had a bad experience, I guess.” He patted the smaller youth’s shoulder. “Take your time, old boy,” he said . “It’s all over now.”
 
Bob sank back onto his flea bag. This was too much for him, his expression of profound bewilderment seemed to say.
 
Frank looked up and essayed a smile. But it was ghastly in result.
 
“Guess you fellows think I’m crazy,” he said, in a shaking voice. “But it’s no joke to have to shoot at a man. I never get over the shakes when it’s necessary.”
 
“What?” cried Jack.
 
“A man?” exploded Bob. “You shot at a man?” Frank nodded. “It was that fellow who had it in for Wimba, I guess,” he said. “The one who charged him with murdering his . That Kikuyu thief, you know.”
 
With an effort, he pulled himself together, shook off Jack’s grip on his shoulder, and got up. “I my head out of the tent to call Matse,” he said, in a firmer voice. “The bearers have a big camp fire going. Between here and the camp fire I could see Wimba. He was approaching our tent. There was no mistaking his form, outlined against the glow of the fire. Then I saw a man spring up from the ground as Wimba passed and stalk after him.
 
“I was scared for Wimba, because the other obviously meant . And it was plain Wimba was of his presence. I didn’t want to yell a warning because his pursuer might leap on Wimba.
 
“So I started forward. But the fellow was creeping up on Wimba. I could see them both like against the fire glow. There was no time to delay. I could see the rascal’s arm back as if to bury a knife in poor old Wimba’s shoulders.”
 
“Then you shot?” asked Jack.
 
Frank nodded. “But I didn’t kill him,” he said. “I aimed to hit his upraised hand, and I guess I did.”
 
“But there were three shots,” objected Bob. “I counted them.”
 
“I shot over his head,” said Frank.
 
“What happened then?” asked Jack.
 
“He got away. And the bearers are chasing him.”
 
Bob’s face became grave. “That’s liable to get us into more trouble with Chief Ruku-Ru.”
 
“I sent Wimba to bring the boys back,” explained Frank. With a laugh, as his self-possession returned he added: “That was the quickest way to put an end to his expressions of .”
 
“Well,” said Jack, “you certainly have put that fellow in your debt. You’ve saved his life twice in one day.”
 
With his usual , Frank’s thought dwelt not on himself and his own actions, but on the other fellow. “Poor Wimba,” he said. “He certainly had a hard time of it.”
 
The excited voices of the returning bearers could be heard without. Bob sank back on his flea bag as Frank went out to hear Wimba’s report. With an , Jack looked at his watch.
 
“So much excitement made me almost forget Dad,” he remarked, going to the corner where the radio sending was set up. Taking his seat and adjusting several loose wire connections, he began manipulating controls.
 
Then he pulled the transmitter toward him and began announcing on a 200-metre wave length a resume of the day’s activities, telling in detail of Wimba’s arrest and trial and of how he had been saved from execution by Frank’s for playing upon Chief Ruku-Ru’s through means of the loudspeaker installed in the council tree.
 
“Luckily we keyed it to 300-metres, Dad,” he explained. “So when we talk to you like this over your 200-metre length, the loudspeaker is inoperative.”
 
He than related the recent episode wherein Frank again had saved Wimba’s life, and concluded with the explanation that they were about to broadcast a concert of band music out of the council tree for the further mystification of the Kikuyus.
 
“Don’t worry about us, Dad,” he said, before hanging up. “We’re making out all right, I expect. I don’t look for any more trouble, after what happened today.”
 
Bob grinned as Jack, his task concluded, turned around to face him.
 
“Well, Mr. Reporter,” he said. “You’re becoming quite expert at making these daily reports.” Jack laughed. “Just the same,” he commented, “it’s not a bad idea, that of these individual portable sets. No matter where Dad is, it’s a pretty safe bet that he heard me.”
 
Each member of the expeditionary party was provided with a small but powerful portable radio set of wide range. Thus whenever, as in the present instance, anybody was absent on side expeditions by in at a hour each night and morning, he received a resume of the day’s activities and of any startling events occurring during the night, which those remaining at the headquarters encampment broadcasted.
 
These sets were the boys’ pride. All three had had a hand in their manufacture. Each set was mounted in a cabinet the size of a portable typewriter case. It contained a regenerative tuner, a and one stage of audio , and was a powerful receiver with two tubes. The secret of its smallness was that it operated on ordinary little flashlight batteries. The head set clamped into the inside of the lid when not in use. Closed, the cabinet could be carried by means of a handle. The whole business weighed less than ten pounds. Throw an insulated wire over a tree, and one would be ready to listen-in.
 
Almost as compact, in its way, was the sending apparatus which now occupied a small collapsible table in one corner of the tent. Table and all, including the motor, fitted into the oblong box yawning emptily on the ground beneath at the present moment—a box two and a half feet by a foot in breadth and nine inches in height.
 
In its construction, the boys had to achieve an apparatus for both sending and receiving. When one , the impact against a sensitive diaphragm closed reception, but the minute the voice of the speaker ceased, the instrument again was ready to receive.
 
It was over this apparatus that the boys planned to broadcast a concert for the benefit and mystification of the Kikuyus, and now that his evening bulletins had been radioed to his father Jack got busy with final preparations. Moving their small talking machine into position and attaching the audion, he laid the records he and Frank had dusted within reach for quick adjustment. All was now ready, and the only thing he waited for was Matse’s report from a reconnaissance into the village that their loudspeaker and apparatus in the council tree had neither been discovered nor with.
 
The council tree arrangement which had been installed the previous night at a late hour, when all in the village were asleep, consisted of one of the portable receiving sets with loop aerial and loudspeaker .
 
Really, the loop aerial had not been necessary. An insulated wire thrown over the topmost branches of the tree would have been sufficient. Installation of the small loop aerial had been considered by Bob as a “piece of dog.” But Frank and Jack had insisted upon it, in the desire to make their proposed concert a superlative success. And they considered the clearness of the voice from the air during Wimba’s trial ample of the extra trouble to which they had gone.
 
Frank returned as Jack finished his preparations, with the announcement that Matse reported the entire village assembled expectantly beneath the council tree about a great fire.
 
“So far as he could see or learn nobody has been into the council tree,” Frank added. “And I guess that’s correct. These Kikuyus wouldn’t go into that tree now, after what happened today, under any circumstances. So your fears are groundless, Bob. Well, let’s go, Jack.”
 
Jack arose and Bob with a humorous made his way to his comrade’s place at the radio apparatus.
 
Because it was bad for his health to be abroad in the night air, he had been elected to act as operative.
 
“You fellows have all the best of it,” he said.
 
Frank and Jack grinned sympathetically, then set out for the village center. They wanted to be on hand to see how Chief Ruku-Ru and his people took the concert.
 
Beside them trailed Wimba, who henceforth was to constitute himself Frank’s faithful shadow, while ahead went the bearers with the exception of four left behind as guards over the encampment.
 
Frank looked back once over his shoulder. “I suppose Bob will be all right,” he said. “Only I don’t quite like the idea of leaving him alone.”
 
“Oh, come on,” said Jack. “To be sure he’ll be all right.”