Through the darkness Barcroft could just distinguish the outlines of a human form crouching in the gorge barely ten yards on his right front, where the cliff began to fall away and form a ravine known as Black Ghyll.
At intervals the man in hiding raised his head and peered cautiously over the thick bush. Not once did he look behind. His attention was centred solely upon the foreshore or else seaward; he was totally oblivious of the fact that he was being watched intently by eight pairs of eyes.
Out to sea everything seemed swallowed up in pitch-black darkness. Only the measured beating of the groundswell upon the shingly shore gave the watchers any indication, apart from their local knowledge, that the wide North Sea was almost at their feet. The stars, too, had disappeared from view, for the mist had increased and was now threatening to develop into a regular sea-fog.
Suddenly the darkness was pierced by a faint ray of light emanating from a mere pinprick of luminosity. Short flash—obscuration—long flash—obscuration—short flash: that was all, but sufficient to indicate that out in that void of Cimmerian gloom some one was signalling.
The suspect rose and leaned forward. It looked as if he were spread-eagled over the gorse-bush. For quite a minute he remained there, then leaving his place of concealment he made his way towards the beach, crouching as stealthily as a panther behind every obstacle until he made sure of his ground.
Perhaps it was the strain of watching in the darkness; perhaps the thought that the suspect might escape; but whatever the motive the fact remained that one of the Scouts, uttering a loud yell, broke from cover and dashed towards the man, brandishing his staff like a Berserk.
"That's done it!" mentally ejaculated Peter. The premature and unauthorised action left no alternative.
"At him, lads!" shouted the petty officer. The fellow stood his ground, expostulating angrily. But his words fell unheeded. Like a pack of hounds the eager and alert youngsters literally threw themselves upon the suspect, and bore him to the ground.
Over and over they rolled, the gorse crackling under their weight. Only a few gaunt stumps prevented the struggling mob from tumbling over the brink of the fearful abyss. Unable to bear a hand Peter and the petty officer stood well-nigh breathless with suspense, expecting every minute to see the suspect and his assailants topple into space.
The struggle was short-lived. The fellow's efforts at resistance ceased. Bound hand and foot and with the ten-stone patrol leader sitting on his chest he realised that the game was up.