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  They were all crouched low to avoid being seen fromthe deck.]

  THE RADIO BOYS ON SECRET SERVICE DUTY

  By GERALD BRECKENRIDGE

  Author of

  "The Radio Boys on the Mexican Border," "The Radio Boys with the RevenueGuards," "The Radio Boys' Search for the Inca's Treasure," "The RadioBoys Rescue the Lost Alaska Expedition."

  A. L. BURT COMPANY

  Publishers, New York

  Copyright, 1922

  By A. L. BURT COMPANY

  THE RADIO BOYS ON SECRET SERVICE DUTY

  Made in "U. S. A."

  CONTENTS

  CHAPTER I--FRANK "LISTENS IN" CHAPTER II--LOOSE ENDS OF A PLOT CHAPTER III--THE MAN OF MYSTERY AGAIN CHAPTER IV--ENTER INSPECTOR BURTON CHAPTER V--THE SOUND DETECTOR CHAPTER VI--IN THE ENEMY'S TOILS CHAPTER VII--A BREAK FOR LIBERTY CHAPTER VIII--CHINATOWN WINS CHAPTER IX--THE POWER OF THE UNDERWORLD CHAPTER X--CARRIED CAPTIVE TO SEA CHAPTER XI--"BEST LAID PLANS" CHAPTER XII--A STORM AT SEA CHAPTER XIII--HOPE IS "IN THE AIR" CHAPTER XIV--THE UPPER HAND REGAINED CHAPTER XV--ABANDON SHIP CHAPTER XVI--DOCTOR MARLEY EXPLAINS CHAPTER XVII--LOST TRAIL CHAPTER XVIII--CLOSING IN CHAPTER XIX--THE SOUND DETECTOR DETECTS CHAPTER XX--IN AT THE DEATH CHAPTER XXI--AT SANTA CRUZ ISLAND CHAPTER XXII--IN THE SMUGGLERS' COVE CHAPTER XXIII--A SIGNAL FROM THE RADIO STATION CHAPTER XXIV--A SPY CAPTURED CHAPTER XXV--A FORLORN HOPE CHAPTER XXVI--A SURPRISE ATTACK CHAPTER XXVII--BLACK GEORGE CAPTURED CHAPTER XXVIII--REWARDS AHEAD CHAPTER XXIX--A LOOK INTO THE FUTURE

  CHAPTER I--FRANK "LISTENS IN"

  "Excuse me for butting in, stranger," said a pleasant voice at the doorof the Pullman stateroom, "but I heard you talkin' to these boys aboutthe old mining camps in these California mountains. It's kind oftiresome with nobody to talk to, ridin' all day. Mind if I come in?Mebbe I can tell you some things interesting to easterners. I'm anold-timer here."

  "Come right in," said Mr. Temple, rising and extending his hand. "Myname's Temple, George Temple. And this is my son, Bob, and his chums,Jack Hampton and Frank Merrick."

  "My name's Harlan, Ed Harlan," said the other, advancing. "I was bornand raised in the mountains. My dad was a forty-niner from Tennessee."

  He was a slim middle-aged man in black, with a black sombrero worn at arakish angle.

  Those who have read _The Radio Boys on the Mexican Border_ are familiarwith Mr. Temple and the three chums. Living in country homes on the farend of Long Island, they had been drawn by a web of circumstances intointernational intrigue on the Mexican Border. Jack's father,representative of a syndicate of independent oil operators, had beenkidnapped by Mexican rebels seeking to embroil the government with thatof the United States. The boys had gone into Mexico and rescued him. NowMr. Temple, a New York importer, was making a business trip to SanFrancisco and taking them with him.

  Radio had played no unimportant part in their adventures. In fact, ithad been instrumental in bringing them to a successful conclusion. Itwas Mr. Hampton, a scientific man enthusiastic over the development ofradio telephony long before the craze swept the country, who hadintroduced the boys to it. He was licensed by the government to build atransmission station on his Long Island estate and use an 1,800-metrewave length for trans-oceanic experiment. When he went to theSouthwestern oil fields, he also erected a station there, using the samewave length previously assigned him.

  These two stations not only provided exceptional opportunities for theboys to learn the intricacies of radio telephony but also provided amethod of helping defeat the ends sought by the Mexican rebels. In theirinvasion of Mexico, moreover, the boys found several radio stationswhich were links in a chain that had been built by German spiesoperating in Mexico against the United States during the World War.

  Frank and Bob also owned an all-metal airplane outfitted with radio,which had played a leading role in their Mexican border adventure. Frankwas an orphan living with the Temples. Bob's mother was dead. The twoestates of Mr. Hampton and Mr. Temple adjoined. Jack, the oldest of thetrio, was 19, while Frank and Bob were a year younger, Frank being theyoungest of the three. All attended Harrington Hall Military Academy,and were on their summer vacation when the Mexican border adventuresimmediately preceding these about to be recorded occurred.

  On their way to San Francisco the party had gone by a circuitous routethrough Denver in order to visit the Mile High City of the Rockies. Theywere now on the last day of their journey and passing through theSierras down the famous Feather River Canyon.

  Accompanied by Mr. Harlan the group made its way to the observationplatform on the rear of the Flyer. Hour after hour they sat there whilethe scenery about them gradually changed its character with the passingof the afternoon, the mountains giving way to foothills and seeming torecede farther and farther to the rear. In reality, of course, the trainwas drawing away from them and descending into the lower ranges.

  Harlan was a pleasant companion, and from him the boys learned moreintimate history of California than they ever had been able to obtainfrom textbooks. He told them of the days of '49 and the treasureseekers; how the latter had come overland by wagon trails in some cases,fighting Indians and starvation, leaving many in nameless graves by thewayside during the long trek across the desert and through themountains; how, in other cases, the adventurers had sailed inwindjammers, or ships propelled by sails alone and without engine power,spending as much as a year in the long trip from the eastern seaboardclear around South America and Cape Horn, although the majority hadsailed merely to the Isthmus of Panama and crossing by horseback or inwagons, had taken ship on the other side for San Francisco.

  "Those were the days," said Harlan. "Of course, I didn't experience thempersonally, for I'm just a young man now. But my father was aforty-niner, came out from Tennessee. And the stories he used to tell ofSan Francisco in the early days made me mad because I hadn't lived therethen.

  "She was just a crazy little town of crazy little wooden shacks, builtany whichway over the hills, but the people that built her were thehardy spirits of all the world and the breath of romance must have beenin the very air."

  At a question from Frank, who, like his chums, was intensely interestedin these stories of early California, Mr. Harlan launched into adescription of the Spanish Dons inhabiting the land before the invasionof the gold seekers.

  Mexico, he recalled to the boys, used to own California. The bestSpanish families lived there on grants of land from the King of Spainwhich had been passed down from generation to generation.

  The estates were huge, and the Dons lived on them pretty much absolutemasters of their Indians and peons. It was an easy, gracious sort ofexistence, without hurry, without the bustle and haste introduced laterby the Americans with their multifarious machinery. If the Don stirredabroad, he rode a mount jingling with fanciful and costly trappings, andhe himself dressed like a cavalier of old. At night his hacienda wouldresound to music while the gentry from miles around danced and theircarriages and horses filled his ample stables and stood under thedrooping pepper trees.

  Then came the gold seekers scarring the hills of the northern part ofthe state with their mines. And in their wake came the farmers andranchers with their new-fangled farm machinery. They took the richvalleys where the countless herds of the Dons had roamed in the past,and began making that marvelous soil produce crops of wheat. The oldorder with its lazy ways could not survive before the new day with itsenergy and modern business methods. The Dons went to the wall.

&n
bsp; "To-day," said Harlan, in his drawling southern voice, "there are someof their descendants left. But they cut little figure in the present-dayCalifornia."

  Jack spoke up with unexpected heat.

  "Well, I think it's a shame," he said. "I know that we are supposed tobelieve our own ways of living are the best, but I, for one, wishCalifornia had stayed the way it was."

  Bob leaned toward Frank and assumed a confidential tone.

  "He's thinking of Senorita Rafaela," he said.

  She was the daughter of Don Fernandez y Calomares, a wealthy Mexican ofpure Castilian descent living in a palace in northern Mexico. The Donwas leader of the Mexican rebels who, as related in _The Radio Boys onthe Mexican Border_, had captured Mr. Hampton. Jack and Bob in thelatter's airplane had gone to the rescue, and the young Spanish girl hadgiven them valuable aid.

  At Bob's words, which although low spoken were intended to reach Jack'sear, the latter flushed. Then he reached over and pulling Bob's cap downover his eyes started to shake him good-naturedly. In a moment all threeboys were entangled. Mr. Temple laughed and explained the situation toMr. Harlan. The two men watched the chums amusedly, until a sudden lurchas the train whirled around a sharp curve threatened to send Jack flyingoverboard.

  With a quick movement Mr. Harlan seized Jack by the coat and pulled himback to safety.

  "That was a close call," said Mr. Temple gravely. "You boys ought to bemore careful."

  At Oroville, which he explained was in the heart of the apple country,Mr. Harlan left the party. All were sorry to bid him farewell, for hehad been a jolly and informative companion. Dinner was served, and theparty returned to the club car where Mr. Temple settled down with hiscigar and a newspaper. Presently the chums grew tired of reading, andonce more sauntered out to the observation platform.

  They would not sleep aboard the train again as they would reach theirdestination near midnight. For a time they gossiped in low voices, so asnot to disturb two men whispering together on the other side of theplatform. All three sat in silence, slumped down in their chairs and atfirst staring out at the landscape bathed in magical moonlight.Gradually Jack and Bob yielded to the soporific influences of theirsurroundings, with the car wheels beating a monotonous andsleep-inducing lullaby.

  Presently the two men who had been whispering raised their voicesslightly in argument. Then one ceased abruptly, cast a keen glancetoward the boys, said a word or two in a low voice to his companion, andthey arose and entered the car. Frank, who like his companions had beensitting with his cap pulled down over his eyes, had not been asleep,however, and as the others left the platform he shook Jack and Bob intowakefulness.

  "Did you hear that?" he demanded excitedly.

  His two chums rubbed their eyes, and looked puzzled.

  "Hear what?" asked Jack.

  "What those fellows said."

  "What fellows?" asked Bob.

  "Why, those two men who were out here," Frank said impatiently. "Ibelieve you were actually asleep."

  "Guess I was," said Bob, yawning. "But what was it they said? And werethey talking to you?"

  "They were whispering to each other," said Frank. "I didn't mean tolisten. But they raised their voices, and I overheard. Then one of themlooked our way--to see if we heard, I suppose--and they got up and left."

  "Well, what was it?" demanded Jack.

  "Shh," said Frank, nervously. "The door's open and that man--the one thatgot suspicious of us--is staring out at us. Listen," he whispered, "I'mgoing in to talk to Uncle George. You fellows stretch and yawn presentlyand get up and go to our stateroom. Then pretty soon I'll bring UncleGeorge in, and we can shut the door and I'll tell you."