FullReads

“But, man,” shouted Brixton, “you don’t suppose anything in the world counts beside her, do you?”

“Exactly the point,” urged Craig. “Save her and capture them–both at once.”

“How can you?” fumed Brixton. “If you attempt to telephone from here, that fellow Janeff will overhear and give a warning.”

Regardless of whether Janeff was listening or not, Kennedy was eagerly telephoning to the Woodrock central down in the village. He was using the transmitter and receiver that were connected with the iron tube which he had connected to the two regular house lines.

“Have the ferry held at any cost,” he was ordering. “Don’t let the next boat go out until Mr. Brixton gets there, under any circumstances. Now put that to them straight, central. You know Mr. Brixton has just a little bit of influence around here, and somebody’s head will drop if they let that boat go out before he gets there.”

“Humph!” ejaculated Brixton. “Much good that will do. Why, I suppose our friend Janeff down in the storeroom knows it all now. Come on, let’s grab him.”

Nevertheless there was no sound from the detectaphone which would indicate that he had overheard and was spreading the alarm. He was there yet, for we could hear him clear his throat once or twice.

“No,” replied Kennedy calmly, “he knows nothing about it. I didn’t use any ordinary means to prepare against the experts who have brought this situation about. That message you heard me send went out over what we call the ‘phantom circuit.'”

“The phantom circuit?” repeated Brixton, chafing at the delay.

“Yes, it seems fantastic at first, I suppose,” pursued Kennedy calmly; “but, after all, it is in accordance with the laws of electricity. It’s no use fretting and fuming, Mr. Brixton. If Janeff can wait, we’ll have to do so, too. Suppose we should start and this Kronski should change his plans at the last minute? How would we find it out? By telepathy? Believe me, sir, it is better to wait here a minute and trust to the phantom circuit than to mere chance.”

“But suppose he should cut the line,” I put in.

Kennedy smiled. “I have provided for that, Walter, in the way I installed the thing. I took good care that we could not be cut off that way. We can hear everything ourselves, but we cannot be overheard. He knows nothing. You see, I took advantage of the fact that additional telephones or so-called phantom lines can be superposed on existing physical lines. It is possible to obtain a third circuit from two similar metallic circuits by using for each side of this third circuit the two wires of each of the other circuits in multiple. All three circuits are independent, too.

“The third telephone current enters the wires of the first circuit, as it were, and returns along the wires of the second circuit. There are several ways of doing it. One is to use retardation or choke-coils bridged across the two metallic circuits at both ends, with taps taken from the middle points of each. But the more desirable method is the one you saw me install this afternoon. I introduced repeating-coils into the circuits at both ends. Technically, the third circuit is then taken off from the mid-points of the secondaries or line windings of these repeating coils.

“The current on a long-distance line is alternating in character, and it passes readily through a repeating-coil. The only effect it has on the transmission is slightly reducing the volume. The current passes into the repeating-coil, then divides and passes through the two line wires. At the other end the halves balance, so to speak. Thus, currents passing over a phantom circuit don’t set up currents in the terminal apparatus of the side circuits. Consequently, a conversation carried on over the phantom circuit will not be heard in either side circuit, nor does a conversation on one side circuit affect the phantom. We could all talk at once without interfering with each other.”