The cloud was around them—dim—silent—ghostly! And dark!

And the other ships—had they dived, fallen? Or, were they but the phantoms of over-stimulated imagination?

They had come together—but Don realized that he had heard no crash.

Hastily he pulled out of the dive. Soberly he turned the nose toward Mystery Airport—baffled—not knowing what to think, what to believe!

CHAPTER IV
TEMPEST AND TREACHERY

Seeing the direction taken by Don, Garry, using the light of the ever increasing flashes in the North, scribbled rapidly and sent a bit of paper forward.

“Going back?” he asked Don in that fashion.

As a vivid blaze of forked lightning leaped across the sky, Don nodded.

For answer Garry extended his arm, outward and downward.

The green flare, floating slowly downward, lit up the swamp beneath the Dragonfly.