The Boy Inventors Radio Telephone | Page 9

days after their experience with the eccentric professor, Mr. Chadwick summoned them to his private workshop. The boys, who had been at work on the Wondership, the flying automobile with which they had met such surprising adventures in Brazil, obeyed the summons with alacrity. It was delivered to them by Jupe, the negro factotum of the place.
"Massa Chadwick send me on de bustelbolorium," explained Jupe, who had a vocabulary that was all his own, "for yo' alls to come right away by his laburnumtory."
"All right, Jupe, we'll be right over," said Jack, "just as soon as we've got some of this grease off our hands."
The boys' workshop was equipped with a washbasin and they soon made themselves presentable. Then they hurried to Mr. Chadwick's workshop. They found him standing before a roughly-built table on which were ranged some odd-looking bits of apparatus.
There was a gasoline motor in one corner, geared to a generator--or what appeared to be one--from which feed wires led to a square metal box on the table. Attached to this metal box was a sort of horn-shaped mouthpiece something like the transmitter of a telephone. Hanging from its side was what looked like an enlarged telephone receiver. Jack regarded his father questioningly.
"You sent for us, dad?"
"Yes, Jack," was the reply. "I'm in a quandary. Have you any idea what this apparatus is?"
Both boys shook their heads.
"Looks like some kind of a telephone," ventured Tom.
"It is a telephone," replied Mr. Chadwick.
"But--but--where are the wires?" asked Jack, glancing about him, "or haven't you connected it up yet?"
"It's connected up as much as it will ever be," said Mr. Chadwick with a smile. "Can't you guess what it is?"
"I've got it," cried Jack suddenly. "It's a wireless telephone."
"That's right," admitted his father, and, in response to a flood of questions from the boys, he told them how he had been working day and night to bring the device to perfection.
"Now," he said, as he concluded, "I want you boys to go down to that shed that was put up last week at the northwest corner of the orchard."
"The one that was put up to store gasoline?" asked Tom.
"I said it was for that purpose in order to avoid questions till I had my work completed," said Mr. Chadwick with a smile. "Here is the key to it. Inside you will find an apparatus similar to this one. Start the dynamo and then stand in front of the transmitter and place the receiver to your ear. If you don't hear anything at once use the inductor to tune your a?rial earth circuit to the transmitted current from my end just exactly as you would tune up a wireless telegraph instrument to catch certain wave lengths from another instrument"
"Then the principle of the radio telephone is the same as that of the wireless telephone?" asked Tom.
"I'll explain that to you later in as plain language as I can," said the inventor, "but now I am anxious to see how this instrument will transmit sound."
The boys were excited. Anything novel in the way of science attracted their bright, active minds as an electromagnet attracts steel. The idea of a wireless telephone, of the possibility of transmitting actual speech through space, just as the dots and dashes of the wireless telegraph are sped through the ether, quickened their inventive faculties to the highest pitch. Both felt a glow of pride that they had been selected, even before their father's scientific friends, to make the first test of this wonderful new invention.
They hurried across the broad lawn that intervened between the workshops and the orchard where the newly erected shed stood, and which, it had been given out, was to serve for the storage of gasoline. Unlocking the door, they found inside an apparatus resembling in almost every detail the one in Mr. Chadwick's workshop.
Jack's hands fairly trembled as he started up the motor and the generator began to buzz. With shining eyes and throbbing pulses he placed the receiver to his ear as his father had directed. But the next moment a flood of disappointment swept through him.
"Well?" demanded Tom, himself a tiptoe with expectation.
"Nothing doing," replied Jack, shaking his head. "I guess the thing isn't at a practical stage yet."
"Wait a minute, give it a chance," urged Tom. "By the way, how about that tuning device, have you tried that yet?"
"No, good gracious, my head must be turning into solid ivory from the neck up. I guess that's just what the trouble is."
Jack began carefully sliding a small block connected to the instruments up and down the coiled wire which formed the tuning apparatus, and brought the sending and receiving ends into harmony just as if they had been two musical instruments. When the right electric "chord" was struck he should be able