He could see quite clearly the impress of "Crumbs's" body as it had lain upon the ground. And as he stood looking upon this impression he observed that "Crumbs" had made what might be called a crude pattern with pebbles—a row of parallel lines. John was able to make out, in all, three separate lines of stones.
For a long minute he remained looking down upon these innocent-seeming pebbles laid out with childish regularity. Then gradually his first suspicions returned. His attention ran along the orderly row of little stones—a third and a fourth time.
And suddenly a vivid light blazed in his eyes. He uttered an exclamation under his breath.
"Great Scott! so that's it."
His whole mind focused upon the pebbles; he began to speak in measured tones.
"Dot-dash-dot-dash; dash-dash-dash."
As the words left his lips on the solitude of the sands, he was conscious of a quick thrill of excitement. The stones laid thus innocently held a sinister meaning spelt out in the Morse code. Two pebbles lay together, then further to the right an isolated pebble, then again two pebbles.
"Dash-dot-dash," John interpreted.
The message was quite a long one. With a glance at the cliff edge—he knew that "Crumbs" was safely in his quarters—John took out his pocket-book and made a faithful copy of "Crumbs's" laborious message.
When he had copied it all down he made his way back to the fort, pondering upon the significance of his discovery. For whom was the message intended? Both Hobin and Commander Grieves had told him that the possibility of any enemy signalling from the fort, or to the fort from outside, had been completely eliminated, and had said, "We should instantly see any light that might be exhibited by an enemy."