"That player knows what he's about," was Herb's tribute.

"And how perfectly we heard every note," cried Joe. "We certainly made a ten strike, Bob, when we rigged up that new aerial. It's got the other beaten twenty ways."

"I guess you're right about that," said Jimmy. "I don't grudge a minute of the time you spent this afternoon in putting it up. It was worth all the trouble."

Bob looked hard at him, but Jimmy was as sober as a judge, and before either Bob or Joe could frame a suitable retort the crashing notes of a military band came to their ears and put from them the thought of anything else. It was a medley that the band played, composed of well-known airs ranging from "Hail Columbia" to "Dixie" and so inspiring was it that the boys' hands were moving and their feet jigging in time with the music all through the performance.

For fully two hours they sat entranced through a varied program that included things so dissimilar as famous grand opera selections, the plaintive melodies of Hawaiian guitars, and some jazz, and when at last the list was ended the boys sat back with a sigh of satisfaction, their faces flushed and their eyes shining.

"Ever hear anything like it?" asked Bob, as he relaxed into his chair and took off his ear pieces.

"It's the best ever!" declared Joe. "And to think that we can have something like it almost any night we choose, and all of that without going out of this room!"

"That's the beauty of it," Bob a.s.sented. "To hear a concert that included such fine talent as that we'd have to go to New York. That would mean all the time and trouble of dressing up, the long ride on the railroad train, the getting back home at two or three o'clock in the morning, to say nothing of the ten dollars apiece or thereabouts that we'd have to pay for train fare and tickets for the concert. For us four that would mean about forty dollars. Now we haven't paid forty cents, not even one cent, we haven't had to dress, we've sat around here lazy and comfy, we can go to bed whenever we like, and we've had the concert just the same. And what we did to-night we can do any night. I tell you, fellows, we haven't begun yet to realize what a wonderful thing this radio is. It's simply a miracle."

"Right you are," agreed Joe. "And just remember that what's true of us four is true of four thousand or perhaps four hundred thousand. Take the biggest concert hall in the United States and perhaps it will hold five thousand. When it's full, everybody else has to stay away. But there's no staying away with radio. And every one has as good a seat as any one else. Think where that concert's been heard to-night. People out as far as Chicago and Detroit have heard it. They've listened to it on board of ships out at sea. In lonely farmhouses people have enjoyed it. Men sitting around campfires up in the Adirondacks have had receivers at their ears. Sick people and cripples lying on their beds have been cheered by it. Lonely people in hotel rooms far away from home have found pleasure in it. There's absolutely no limit to what the radio can do. It seems to me that it throws in the shade everything else that's ever been invented."

"You haven't put it a bit too strong," chimed in Herb. "But talking about a lot of people hearing it makes me think that perhaps we fellows have been a bit selfish."

"What do you mean?" asked Jimmy in some surprise. "It isn't so long ago that we got the old folks and sick folks together and gave them a concert at Doctor Dale's house-Joel Banks and Aunty Bixby and the rest of them."

"I don't mean that," explained Herb. "That was all right as far as it went, and I hope we'll do it soon again. But what I have in mind are our own folks and our friends. Our fathers and mothers haven't heard much of this concert to-night, and there are some of the fellows that we might have invited in."

"But we have only four sets of ear pieces," objected Jimmy. "I suppose of course we could attach a few more--"

"I get Herb's idea," interrupted Bob, "and it's a good one. He thinks that we ought to have a loud-speaker-a horn that would fill the room with sound and do away with the ear pieces altogether."

"You hit the bull's-eye the first time," Herb conceded. "In other words, instead of having a concert for four have it for fourteen or forty."

CHAPTER IV-FACING THE BULLY

The radio boys ruminated over Herb's suggestion for a little while.

"The idea itself is all right," p.r.o.nounced Joe slowly, "but the trouble is that we couldn't do it very well with this set, which is the best we've been able to make so far. We can hear the sound that comes over the wire well with these earpieces glued to our ears, but the sound would be lost if it were spread all over the room."

"Wouldn't the horn help out on that?" asked Herb.

"Not by itself, it wouldn't," answered Bob. "It's a mistake to think that the horn itself makes the sound or increases its loudness. The only use of the horn is to act as a relay for the diaphragm of the receiver and connect it with the air in the room. But the sound itself must first be in the receiver. And with a crystal detector, such as we're using in this set, I'm afraid that we couldn't get volume of sound enough. It would be spread out over the room so thinly that no one would be able to hear anything. We'll have to amplify the sound, and to do that there's nothing better than a vacuum tube. That's the best thing that the world has discovered so far."

"I guess it is," remarked Jimmy. "Doctor Dale has one in his set."

"Yes," chimed in Joe. "He even has more than one. The more there are the louder and clearer the sound."

"I don't suppose we could make one," Herb remarked.

"No; that's one thing that costs real money," replied Bob. "But don't let that bother you. I've got quite a lot left of that hundred dollars of the Ferberton prize, and there's nothing I'd rather spend it for than to improve the radio set."

"Count me in on that, too," said Joe. "I've scarcely touched my fifty."

"How about the horn?" queried Jimmy. "Will that have to be bought, too?"

"No," replied Bob. "That's something you can make. That is, if you're not too tired from the work you did on setting up the aerial this afternoon."

"But," objected Jimmy, ignoring the gibe, "I don't know anything about working in tin or steel. I haven't any tools for that."

"The horn doesn't have to be made of metal," answered Bob. "In fact, it's better if it's not. Some horns are even made of concrete--"

"Use your head for that, Jimmy," broke in Herb irreverently.

"But best of all," Bob continued, while Jimmy favored the interrupter with a glare, "is to make the horn of wood. Take some good hard wood, like mahogany or maple, polish the inside with sandpaper after you've hollowed it out, give it a coat of varnish or sh.e.l.lac, and you'll have a horn that can't be beaten. It's very simple."

"Sure!" said Jimmy sarcastically. "Very simple! Just like that! Simple when you say it quick. Simple as the fellow that tells me how to do it."

"Just imagine you're hollowing out a doughnut," put in Joe, grinning.

"You're an expert at that."

"I'll tell the world he is," agreed Herb, with enthusiasm.

"That reminds me," said Bob, "that there's some pie in the pantry and sarsaparilla in the ice-box that mother told me to pa.s.s around among you fellows. That is, of course, if you care for it," he added, as he paused in seeming doubt.

"If we care for it!" cried Jimmy, the creases of perplexity in his brow disappearing as if by magic. "Lead me to that pie. I'll fall on its neck like a long-lost brother."

"It'll fall into your neck, you mean," chuckled Herb, and in less than two minutes saw his prophecy verified.

"And now," said Bob, after the last crumb and drop had disappeared, "I don't want to tie the can to you fellows, but I hear dad moving around and locking up, and that's a sign to skiddoo. We'll think over that idea of Herb's and get a tip from Doctor Dale as to the best way to go about it."

There was a chorus of hearty good-nights and the radio boys separated.

Two days later, as Bob and Joe were coming home from school, the latter, looking behind him, gave vent to an exclamation that drew Bob's attention.

"What's up?" he asked, turning his head in the same direction.

"It's Buck Looker and his bunch!" exclaimed Joe, a flush mounting to his brow and his eyes beginning to flame. "He's been careful to keep out of my way so far. Let's wait here until he catches up to us."

"You'll wait a long time then, I guess," replied Bob, "for he's seen us, too, and he's slowing up already. He doesn't seem a bit anxious to overtake us."

"Then we'll have to go back and meet him," said Joe grimly. "I'm going to have it out with him right here and now. He needn't think he's going to get away scot free after the trick he played on me."

"What's the use, Joe?" counseled Bob. "You can't prove it on him and he'll only lie out of it. It's bad policy to kick a skunk."

But Joe had already turned and was striding rapidly back toward Buck and his companions, and Bob went along with him.

There was a hurried confabulation between Buck and his cronies as they saw Bob and Joe advancing toward them, and a hasty looking from side to side, as though to seek some means of escape. But there was no street handy to turn into, and as it would have been too rank a confession of cowardice to turn their backs and run, the trio a.s.sumed a defiant att.i.tude and waited the approach of the swiftly moving couple.