The Radio Boys at Ocean Point: or, The Message that Saved the Ship. Chapman Allen

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СКАЧАТЬ showing Chinese cities and customs and types. Both the eye and the ear would be taught at the same time, and in a most interesting way, it seems to me. What do you think of the idea?”

      “Fine,” said Bob.

      “Dandy,” agreed Joe. “There wouldn’t be any lack of interest in those classes. The boys would be eager to have the time for them come.”

      “Well,” smiled Mr. Preston, “it’s only an idea as yet, but it’s perfectly feasible and I shouldn’t be surprised to see it in general use in a year or two.”

      He turned into a side street just then with a pleasant good-bye, and the boys went on their way together, picking up Jimmy, who was just emerging from a store.

      “What was Mr. Preston talking to you about?” asked Jimmy, with some curiosity, for he had witnessed the parting. “Hauling you over the coals, was he, for something you’ve done or haven’t done?”

      “Nothing like that,” replied Joe. “We just found out that he is a radio fan like the rest of us.”

      “Funny, isn’t it, how that thing is spreading?” murmured Jimmy musingly. “You couldn’t throw a stone now without hitting somebody who is interested in radio.”

      “All the same, I wish he hadn’t caught up to us when he did,” grumbled Joe. “I was just going to mix it with Buck Looker when he came along.”

      “Buck has lots of luck,” commented Jimmy. “Tell me all about it.”

      They told him all the details of the meeting, and became so engrossed in it that they almost ran into Dr. Dale, who was just coming up from the railroad station.

      He greeted them with great cordiality, which met with quite as hearty a response on their part, for the minister was a prime favorite with them and they always felt at their ease with him. There was nothing prim or professional about him, and his influence among the young people was unbounded.

      He chatted with them for a few minutes until they reached Bob’s gate.

      “Won’t you come up on the porch for a few minutes, Doctor?” asked Bob. “There are some things we’d like to ask you about radio.”

      “Certainly I will,” replied the doctor, with a smile. “There’s not much that I’d rather talk about. In fact, I was just about to tell you of an interesting experience that I had this very afternoon.”

      He went with the boys up the steps and dropped into the chair that Bob drew up for him.

      “Tell us about that first, Doctor,” urged Bob. “Our questions can come afterward.”

      “I just had the luck to get on a train coming home that had a car attached to it where they were trying out a new radio system,” replied the minister. “I heard about it from the conductor, whom I know very well, and he arranged it so that I could go into the car where they were making the experiments. They had a radio set in there with a horn, and the set was connected with an aerial on the roof of the car. They sent out signals to various stations while the train was going along at the rate of forty miles an hour, and got replies that we could hear as plainly as though one of the people in the car were talking to the others. The whole thing was a complete success, and one of the officials of the road who happened to be in the party told me that the express trains on the road were going to be equipped with it.

      “Of course, if one road does that, it will not be any time before all the others will, too. It’ll not be long before we can be sitting in a car traveling, let us say from New York to Albany, and chat with a friend who may be on another train traveling between Chicago and Denver. Or if a business man has started from New York to Chicago and happens to remember something important in his office he can call up his manager and give him directions just the same as though he pressed a buzzer and called him in from the next room.”

      “It sounds like magic,” remarked Bob, drawing a long breath.

      “If we’d even talked about such things a few hundred years ago we’d have been burned at the stake as wizards,” laughed the doctor.

      “The most important thing about this railroad development,” he went on, “is not the convenience it may be in social and business life, but in the prevention of accidents. As it is now, after a train leaves a station it can’t get any orders or information until it gets to the next station. A train may be coming toward it head on, or another train ahead of it and going in the same direction may be stalled. Often in the first case orders have come to the station agent to hold a train until another one has passed. But the station agent gets the message just a minute too late, and the train has already left the station and is rushing on to its fate. Then all the agent can do is to shudder and wait for news of the crash. With the radio equipment he can call up the train, tell of the danger, and direct it to come back.

      “Or take the second case where a train is stopped by some accident and knows that another train is coming behind it on the same track and is due in a few minutes. All they can do now is to send back a man with a red flag to stop the second train. But it may be foggy or dark, and the engineer of the second train doesn’t see the flags and comes plunging on into the first train. With the radio, the instant a train is halted for any reason, it can send a message to the second train telling just where it is and warning of the danger. Hundreds have been killed and millions of dollars in property have been lost in the past just because of the old conditions. With the radio installed on trains, that sort of thing will be made almost impossible in the future.

      “But there,” he said, with a smile, “I came up here to answer your questions, and I’ve been doing all the talking. Now just what is it you wanted to ask me about radio?”

      CHAPTER VI – THE WONDERFUL TUBE

      “It’s about getting a vacuum tube,” replied Bob, in answer to the doctor’s question. “The crystal detector is all right when we use the ear pieces. But we got to thinking about a horn so that lots of people could enjoy the concerts at the same time, and we figured that the crystal wouldn’t be quite good enough for that.”

      The doctor smiled genially.

      “I knew you’d be wanting that sooner or later,” he said. “It’s the second natural step in radio development. While you were still getting familiar with the working of the wireless, the crystal would do very well. But there comes a time to all amateurs when they get to hankering after something that is undeniably better. And the vacuum tube is that thing.”

      “It seems funny to me that the vacuum tube could have any use in radio,” put in Jimmy. “I never thought of it in any way but as being used for an electric light.”

      “Neither did lots of other people,” replied the doctor, smiling. “Even Mr. Edison himself didn’t realize what its possibilities were. He did, though, discover some very curious things about it. In fact, he made the first step that led to its use for radio. He put a plate in one of his lamps. The plate didn’t touch the filament, but formed part of a circuit of its own with a current indicator attached. Then when he turned on the light and the filament began to glow, the needle of the indicator began to twitch. Since the filament and the plate weren’t touching, the movement of the needle indicated that the electricity must have jumped the gap between the two. But this simply showed that an invisible connection was established between the filament and the plate and nothing more came of it at the time.

      “Now, it’s likely that even yet we shouldn’t have had that discovery of Edison’s used for the development of radio if it hadn’t been for the new theory of what electricity СКАЧАТЬ