“L-I.”
There followed a period of listenings with the receiving switch over and the “watch-case” receivers closely clamped to the young operator’s ears. But no answer came.
A worried look crept over Jack’s countenance. This silence was ominous. Once more he manipulated the key with nimble fingers. The spark squealing and crackling shot bluely hither and thither.
But to the electrical appeals sent broadcast into the atmosphere, space vouchsafed no answer.
CHAPTER III—THE CIPHER CODE
A sudden break in the rhythmic pulse of the engine reached Tom’s alert ears at this instant. Without speaking he hastened from the cabin to the engine-room, using, for this purpose, a door cut in the forward bulkhead. He found that one of the cylinders was missing fire and traced the trouble to a badly sooted plug.
While he was adjusting the trouble Jack stuck to his key. He would pound out his “S-K” call furiously for an interval, and then listen intently for even the faintest indication of a response. The lad tried various adjustments, of the potentiometer, which regulates the voltage and current supplied to the detector, and operated his receiving tuning coil in various ways. But though he tried for wave lengths from two hundred meters up to fifteen hundred, not a whisper came out of the void of silence about them.
“I’ll call once more,” said the lad to himself in a determined voice, “it’s our duty to do all we can and keep at it all the time. Of course, if the Sea King has met with a really serious disaster her wireless may be out of order and—Hullo! Here’s something coming now!”
Something was coming, sure enough!
As Jack clamped the receivers to his ears a hail of dots and dashes beat against his organs of hearing. Somebody was transmitting a message at a furious rate. Expert as the lad was, it was all he could do to make head or tail of it. His pencil fairly flew over the recording pad, and when he got through he had nothing for his pains but a sheet covered with figures, and again that annoyingly mysterious signature X. Y. Z.