ON THE TRAIL
“I can see the lights from the camp!” Bob exclaimed. “Use your eyes, fellows. A little to the left of us, through the trees.”
“Well, it’s about time,” groaned Jimmy, as they all looked in the direction indicated. “I was just getting ready to lie down and die peacefully. I couldn’t travel another mile if you paid me for it.”
“Oh, buck up, Doughnuts, and get a move on!” exclaimed Bob. “You never know what you can do until you try. Come on, let’s take it on the double.”
He and Joe and Herbert broke into a lively trot, and rather than be left behind Jimmy overcame his reluctance for further effort, and with much puffing and blowing and fragmentary complaint managed to hold the pace until they arrived at the mess house.
Luckily for them, supper had been delayed owing to the failure of some supplies to arrive on time, and the lumbermen had just started eating when the radio boys burst in through the door.
The lumbermen stopped eating long enough to welcome their arrival, and they found their places set as usual.
“Glory be!” exclaimed Jimmy, as he slid into his chair. “If there were a pie-eating contest on to-night, I could show you fellows some real class. I feel empty right down to my toes.”
“It’s lucky we got a head start, Champ,” remarked one of the men, with a grin. “Pass everything down this way, you amateurs. There’s a professional here wants to show us some fancy eating.”
By this time Jimmy was too busily occupied to make any answer, and the other radio boys were also showing good appetites. The long trip and the excitement of their discovery of the secret code had sharpened their naturally keen appetites until for once they all felt on equal terms with the lumbermen. Jimmy surpassed himself, and great was the admiration expressed for his ability as a trencherman.
After supper the boys sought out Mr. Fennington and told him of their discovery in the lonely cabin. Then Bob showed him the copy he had made of the code, and Mr. Fennington studied this a long time with knit brows.
“There seems little doubt that you boys have unearthed an important clue, and one that may easily lead to the discovery of the crooks who stole my merchandise,” he said, at length. “I suppose I should put this information in the hands of the police. And yet perhaps we had better say nothing until we learn something further. With your radio outfit you may be able to catch another code message that would give us more definite information, and then it would be time enough to call in the police.”
“I think that would be the best thing to do, Dad,” agreed Herb. “As soon as we get back home we’ll fix it so one of us will be at the set a good part of every afternoon and evening, and we’ll be almost certain to catch some more messages like the last one.”
His father nodded, and was still considering the matter when there came a knock at the door. Herb crossed over and opened it, and he and his friends uttered exclamations of astonishment and delight as they recognized the visitor. He was none other than Frank Brandon, the government radio inspector.
On his part, he was no less pleased to see them, and they all shook hands heartily, with many questions and explanations, after which the radio inspector was introduced to Mr. Fennington.
“I suppose you’re all wondering what I’m doing up here,” he said, after the greetings were over.
“Yes, in a way,” admitted Bob. “Although we know that your position calls you all over, and we may expect to meet you almost any old place.”
“Yes, that’s a fact,” replied Brandon. “I’m up here on the same old business, too. Somewhere in this neighborhood there’s an unauthorized sending station, but in these thick woods it may prove a rather difficult place to locate exactly. However, it will only be a matter of time when we nail it.”
The boys glanced at one another, and the same thought was in all their minds. They remembered the radio apparatus they had seen in the lonely cabin, and had little doubt that this would prove to be the unauthorized station of which the radio man was in search.
He must have read something of this in their expression, for he looked searchingly from one to another.
“Looks to me as though you fellows knew something,” he remarked. “I might have known if there was anything going on in the radio line within fifty miles of where you are that you’d know something about it.”
“Well, I’ve got a hunch that we could lead you right to the place you’re looking for,” said Bob quietly.
“What?” shouted Brandon, leaping excitedly to his feet. “Do you really mean that? Tell me all about it.”
For the second time that evening Bob recounted the happenings of their eventful excursion, while the radio inspector listened intently, throwing in a question here and there. When Bob had finished he made no comment for a few minutes.
Then he took the copy of the code and examined it intently, jotting down phrases here and there in his own notebook.
“Well,” he said at length, “this looks to be a much bigger thing than I had supposed. Of course I heard of the robbery of the motor-truck, but I never for a moment connected that with this sending station we’ve been looking for. It seems fairly evident, though, that if we can lay our hands on the operators of the unauthorized sending outfit, we’ll also have the perpetrators of that hold-up. This is a case where we’ll have to think out every move before we act.”
“Just before you arrived I was considering the advisability of putting the matter into the hands of the police,” said Mr. Fennington. “What would you do?”
“Keep the whole thing to ourselves for the present,” said Mr. Brandon decisively. “I’ll send for a couple of good men to come up here and help me, and we’ll keep a watch on that cabin for a few days. If this thing got into the papers, it would put the crooks on their guard, and probably spoil our chances of catching them and getting back the loot. I’ve got a small but extremely efficient receiving and sending set in my car, and if any more code messages are sent out we’ll catch them.”
His confidence was contagious, and the boys felt almost as though the capture of the criminals had already been accomplished.
“What puzzles me, though,” remarked Mr. Fennington, “is how you knew that there was an unauthorized radio sending station in this neighborhood, Mr. Brandon. I should think it would be almost impossible to locate such a station, even approximately.”
“On the contrary,” replied Frank Brandon, “it is little more than a matter of routine. Probably any of these radio fiends here could explain the method as well as I can, but I’ll try to make it plain to you.
“There is a certain type of aerial that has what we call ‘directional’ properties, that is, when it is shifted around, the incoming signals will be loudest when this loop aerial, as it is called, is directly in line with the sending station. The receiving antenna is wound on a square frame, and when the signals are received at their maximum strength, we know that the frame is in a practically straight line with the sending station we’re after.”
“Yes, but that still leaves you in the dark as to whether the station is one mile away or a hundred miles,” observed Mr. Fennington, as Brandon paused.
“That’s very true,” answered the other. “And for that reason we can’t stop at using just one loop aerial. What we actually do is to have three stations, each one equipped with a loop. These three stations are located a good many miles apart. Now, with these three loops, we have three lines of direction. We lay out these lines on a chart of the territory, and where they intersect, is the place where the unlicensed station is located. Is that clear?”
“Perfectly,” said Mr. Fennington. “But what looks like a point on the map may be a large space on the actual territory.”
“Oh, yes, our work isn’t done by any means after we have got our first rough bearings,” continued Brandon. “Having determined the approximate position, we take the loops and receivers to what we know is a place quite near the station we’re after, and then we repeat the former process. This time it is much more accurate. Gradually we draw the net tighter until we find the antenna belonging to the offender, and then—well, we make him wish he hadn’t tried to fool the government.”
“You certainly have it reduced to an exact science,” acknowledged Mr. Fennington. “I don’t wonder that everybody interested in radio gets to be a fanatic.”
“We’ll make a ‘bug’ out of you before we get through, Dad,” declared Herb, grinning.
“If my load of silk is recovered through the agency of radio, I’ll be enthusiastic enough over it to suit even you fellows,” said his father. “It will mean the best set that money can buy for you if I get it back.”
“We’ll hold you to that promise,” threatened Herb. “Radio can do anything,” he added, with the conviction of a devotee.
“Well, pretty nearly everything,” qualified Mr. Brandon. “A little while ago it was considered marvelous that we could transmit the voice by radio, and now the transmission of photographs by radio has been successfully accomplished.”
“What!” exclaimed Mr. Fennington incredulously. “Do you mean to say that an actual recognizable photograph has been sent through the air by radio? That seems almost too much to believe.”
“Nevertheless, it has been done,” insisted Frank Brandon. “I saw the actual reproduction of one that had been sent from Italy to New York by the wireless route, and while I can’t claim that it was perfect, still it was as plain as the average newspaper picture. And don’t forget that this is a new phase of the game, and is not past the experimental stage yet.”
“Well, after that, I am inclined to agree with Herbert that ‘radio can do anything,’” admitted Mr. Fennington.
“I don’t think we’ll have much trouble making a convert of you,” laughed the radio inspector. “No doubt the quickest way, though, will be to recover your stolen shipment, so we’ll start working in that direction the first thing in the morning.”
And in this he was as good as his word. He was up betimes, getting in touch with headquarters by means of his compact portable outfit. He kept at work until he had received the promise of two trustworthy men, who were to report to him at the lumber camp as soon as they could get there. Then he routed out the radio boys, and after a hasty breakfast they all set out to locate the cabin where the boys had found the code key.