Wrapped in their warm rugs--for, at this elevation, though in mid-Africa, a rug is almost a necessity at night--the boys were soon asleep beside the fire, and no one was left on guard except dear old Vike.
He slept with one eye open, or one ear at all events, and was likely to give a good account of any savage who might come prowling around the camp.
But, by way of making assurance doubly sure, the adventurers slept with loaded revolvers close beside them.
They slept heavily.
And that, too, despite the roaring of lions far down in the plains below, and the unearthly shrieks of goodness knows what, that came, ever and again, from the dark depths of the forest.
The sun was just rising over the distant green and hazy horizon when Duncan sat up.
He rubbed his eyes, and gazed around him almost wildly.
"Conal, Frank," he cried them, "awake! awake! Where is the balloon?"
Had there been any echo it might well have answered "Where?"
The balloon was gone!