Although they cruised around for more than an hour, they saw not the slightest sign of life either about the base of the cliff or on the Polucca place, which, keeping well out from shore as they did, they could plainly distinguish. As the gloom deepened they felt that it was almost useless to continue, but Frank decided that they should wait a while longer.
"These fellows aren't likely to move around much in daylight. Night is the time for their operations," he pointed out. "We'll hang around for a while longer."
Twilight deepened into darkness and the lights of Bayport could be seen as a yellow haze through the mist at the distant extremity of the bay. The cliff was but a dark smudge in the night and the waves broke against the rocks with a lonely sound.
Suddenly, through the darkness, they heard a muffled sound. Their own boat was running along quietly and they listened.
"Another boat," remarked Tony, in a whisper.
It was, indeed, another motorboat, and it was near the base of the cliff. At last they could distinguish a faint light, and toward this light they began to move slowly.
They were tense with excitement. Everything might depend on the events of the next few minutes.
