“It’s a success, Ned!  I’ve struck it!” cried Tom, in delight.

“Ouch!  You struck me, you mean!” replied Ned, rubbing his shoulder, where the young inventor had imparted a resounding blow of joy.

“What of it?” exclaimed Tom.  “My apparatus works!  I can send a picture by telephone!  It’s great, Ned!”

“But I don’t exactly understand how it happened,” said Ned, in some bewilderment, as he gazed at the selenium plate.

“Neither do I,” admitted Tom, when he had somewhat calmed down.  “That is, I don’t exactly understand what made the thing succeed now, when it wouldn’t work for me a little while ago.  But I’ve got to go into that.  I’ll have to interview that rascal Eradicate, and learn what he did when he played that trick on Koku.  Yes, and I’ll have to see Koku, too.  We’ve got to get at the bottom of this, Ned.”

“I suppose so.  You’ve got your hands full, Tom, with your photo telephone, and the disappearance of Mr. Damon.”

“Yes, and my own airship, too.  I must get after that.  Whew!  A lot of things to do!  But I like work, Ned.  The more the better.”

“Yes, that’s like you, Tom.  But what are you going to get at first?”

“Let me see; the telephone, I think.  I’ll have Rad and Koku in here and talk to them.  I say, you Eradicate!” he called out of the door of the shop, as he saw the colored man going past, holding his shocked arm tenderly.

“Yas, sah, Massa Tom, I’se comin’!  What is it yo’ all wants, Massa Tom?”

“I want you to show me exactly what you did to the wires, and other things in here, when you played that Angel Gabriel trick on your partner Koku.”

“Partner!  He ain’t mah partner!” exclaimed Eradicate with a scowl, for there was not the best of feeling between the two.  Eradicate had served in the Swift family many years, and he rather resented the coming of the giant, who performed many services formerly the province of the colored man.

“Well, never mind what he is, Rad,” laughed Tom.  “You just show me what you did.  Come now, something happened in here, and I want to find out what it was.”

“Oh, suffin done happened all right, Massa Tom.  Yas, sah!  Suffin done happened!” cried Eradicate, with such odd emphasis that Tom and Ned both laughed.

“An’ suffin happened to me,” went on the colored man, rubbing his shocked arm.

“Well, tell us about it,” suggested Tom.

“It was dish yeah way,” proceeded Eradicate.  And he told more in detail how, seeing Koku cleaning and sweeping out the other telephone booth, he had thought of the trick to play on him.  Both telephones had what are called “amplifiers” attached, that could be switched on when needed.  These amplifiers were somewhat like the horn of a phonograph—­they increased, or magnified the sound, so that one could hear a voice from any part of the shop, and need not necessarily have the telephone receiver at his ear.