As he looked it became more and more distinct, and to his astonishment he saw that it was slowly rising, like a huge will-o'-the-wisp that had suddenly risen from the floor of the cavern to float off into the utter blackness of space above.

And even as he stared, gripping Wabi's arm in his excitement, the strange light began to descend, and quickly disappeared! The two boys saw Mukoki slip off into the gloom, and without questioning his motive they followed close behind.

As they progressed the sound of the fall came more and more faintly to their ears.

A blackness deeper than the gloom of the darkest night environed them, and the three now held to one another's arms.

Rod understood why his companions lighted no torches.