“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 aerial 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.