Their plans for the future seemed perfect. They were only waiting for Haverly to get a little stronger, ere commencing their march through the jungle to the upper world and daylight. They had yet to learn that “the best laid schemes o’ mice and men gang aft agley.”
“I hope they will not get into danger,” Mervyn remarked, after a long silence; “it’s rather risky, yet we cannot blame Chenobi for wishing to secure the jewels.”
“He would be in a rather peculiar position above ground without money,” returned Garth, “and I fear he would be too proud to accept help from one of us. Anyway, he and Seymour should be safe enough. They are well armed, and——”
Out of the distance came a sullen muttering, as of far-distant thunder, and at the sound Garth’s sentence died on his lips.
“Whatever’s that?” Wilson asked.
Striding out on deck, Mervyn leaned over the rail, and stood listening for a repetition of the sound. Again it came, low as before, reverberating amid the hills like the roll of many drums.
“I don’t like it,” the scientist muttered, as Garth and the engineer joined him; “have you noticed how remarkably still the water has grown during the last few hours? See how gently the waves come in; there is scarcely more motion than on a mill-pond.”
“What do you infer from that?” asked Garth.
“That we are about to witness some phenomenon peculiar to this underworld,” replied Mervyn. “What form it will take I do not know, but I heartily wish Seymour and the king were back.”
“They should not be long now in any case,” rejoined the engineer; “they have been gone over three hours. I say, we must get the Seal off again. The water’s receding!”