No sound beyond the distant murmur of the waterfall broke the stillness. If the lads could pass the guards stationed in the rocky recess their chances of escape would be most favourable.
Cautiously, and feeling their way step by step, Colin and Desmond entered the gloomy tunnel. As a matter of precaution they had removed their boots, and carried them slung round their necks, and their bare feet made no noise as they encountered the smooth, hard rock that formed the floor of the tunnel.
With beating hearts they approached the hewn-out cavity where they had seen the guards on the occasion of their arrival. The fire no longer burned in the recess. Like the rest of the subterranean passage, the place was in darkness.
Hardly able to credit their good fortune, the chums increased their pace, and gained the narrow track between the waterfall and the end of the gorge.
{Illustration: "'WE'VE DONE IT, BY JOVE!'" [p. [231]}
"We've done it, by Jove!" soliloquised Sinclair. "We're through."
These thoughts had hardly flashed across his mind when a heavy hand descended upon the shoulder of each of the lads. Turning, they found themselves in the grip of a tall, powerfully-built man, while others, springing seemingly from nowhere, barred the way to freedom.
To Colin's and Tiny's astonishment, their captor made no attempt to harm them. With an air of superior detachment, he pointed in the direction of the tunnel, and exclaimed: