Rex Rutherford’s Prophecy.
At the Rectory Roddy sat in his own wireless-room until far into the night, fitting a complete wireless receiving-set into a small cigar-box. The one he had fitted into a tin tobacco-box was efficient in a sense, but the detector being a crystal it was not sufficiently sensitive to suit him.
The one he was constructing was of his own design, with three valves—as the little wireless glow-lamps are called—the batteries and telephones being all contained in the box, which could easily be carried in the pocket together with a small coil of wire which could be strung up anywhere as an aerial, and as “earth” a lamp post, a pillar-box, or running water could be used.
It was nearly three o’clock in the morning before he had finished assembling it, and prior to fixing it in the box he submitted it to a test. Opening the window of his wireless-room he threw the end of the coil of wire outside. Then going out into the moonlight, he took the ball insulator at the end of the wire and fixed it upon a nail he had driven in the wall of the gardener’s potting-shed some time before.
Then, having stretched the wire taut to the house, he went back and attached it to one of the terminal screws of the little set upon which he had been working for many days. The earth-wire of his experimental set he joined up, and then putting on the ’phones listened intently.
Not a tick!
He slowly turned the ebonite knob of the condenser, but to no avail. Raising the wavelength brought no better result. Was it yet another failure? As an experimenter in radio he was used to failures, so it never disheartened him. Failure in prospecting was the same as failure in wireless. He received each rebuff complacently, but with that air of dogged perseverance of which success is ever born.
“Strange!” he remarked aloud. “It certainly should give signals.”
Then he examined the underside of the sheet of ebonite on which the various units were mounted, valves, condensers, etc, when at last he discovered a faulty connexion on the grid-leak. The latter will puzzle the uninitiated, but suffice it to say that so delicate is wireless receiving that over a line drawn by a lead pencil across paper or ebonite with a two-inch scratch in it filled with pencil dust the electric waves will travel. The connexion was not complete at one end. He tightened the little terminal, and suddenly came the expected high-pitched dots and dashes in the Morse code.
“Ah! Stonehaven!” he remarked. Then, by turning the knob of the condenser, a sharp rippling sound was brought in—the automatic transmission from Cologne to Aldershot at seventy words a minute.