Ted and the Telephone

by Sara Ware Bassett

"I know she is a very long-suffering person," smiled the tutor. "Do you recall the white mice you had once, Laurie, and how they got loose and ran all over the house?"

"And the chameleons! And the baby alligator!" chuckled Laurie. "Mother did get her back up over that alligator. She didn't like meeting him in the hall unexpectedly. But she wouldn't mind a thing that wasn't alive."

"You call an electric wire dead then," said Ted with irony.

"Well, no—not precisely," grinned Laurie. "Still I'm certain Mater would be less scared of it than she would of a mouse, even if the wire could kill her and the mouse couldn't."

"Let's return to Mr. Bell and his piano strings," Ted remarked, after the laughter had subsided.

Mr. Hazen's brow contracted thoughtfully and in his leisurely fashion he presently replied:

"You can see, can't you, that if an interrupter caused the electric current to be made and broken at intervals, the number of times it interrupted per second would, for example, correspond to the rate of vibration in one of the strings? In other words, that would be the only string that would answer. Now if you sang into the piano, you would have the rhythmic impulse that set the piano strings vibrating coming directly through the air, while with the battery the impulse would come through the wire and the electromagnets instead. In each case, however, the principle involved would be the same."

"I can see that," said Ted quickly. "Can't you, Laurie?"

His chum nodded.

"Now," continued Mr. Hazen, "just as it was possible to start two or more different notes of the piano echoing varying pitches, so it is possible to have several sets of these make-and-break or intermittent currents start their corresponding strings to answering. In this way one could send several messages at once, each message being toned to a different pitch. All that would be necessary would be to have differently keyed interrupters. This was the principle of the harmonic telegraph at which Mr. Bell was toiling outside the hours of his regular work and through which he hoped to make himself rich and famous. His intention was to break up the various sounds into the dots and dashes of the Morse code and make one wire do what it had previously taken several wires to perform."