"Easily," the green cloud said.

Standing before them was a ship, an exact duplicate of the stratosphere scout.

Not a word passed between the two human beings as they got into the ship. It wasn't necessary to think in order to know what should be done.

"Hey!" cried the green cloud. "Come back here. You can't go away—"

The green cloud ran toward the ship, but it could not destroy it, for to do so would have been murder. One's own thoughts are not to be destroyed by one's self. Hawes realized this. He had tried several times to build a plane, but it always was eaten by a green cloud the second he got it finished. But the green clouds could not eat their own thoughts.

The motor whirred.

"Just a minute, before we leave," the captain said. He closed his eyes. He thought hard of Loetta.

The figure of Loetta appeared in the control cabin beside him.

Captain Hawes touched the controls and the ship soared away.

"I hope you can learn to eat solid food, Loetta," the captain said.