"How strange!" she exclaimed, drawing a long breath.

"Yes; but it's lots of fun, if it IS strange," remarked the small voice of the kitten, and Dorothy turned to find her pet walking in the air a foot or so away from the edge of the roof.

"Come back, Eureka!" she called, in distress, "you'll certainly be killed."

"I have nine lives," said the kitten, purring softly as it walked around in a circle and then came back to the roof; "but I can't lose even one of them by falling in this country, because I really couldn't manage to fall if I wanted to."

"Does the air bear up your weight?" asked the girl.

"Of course; can't you see?" and again the kitten wandered into the air and back to the edge of the roof.

"It's wonderful!" said Dorothy.

"Suppose we let Eureka go down to the street and get some one to help us," suggested Zeb, who had been even more amazed than Dorothy at these strange happenings.

"Perhaps we can walk on the air ourselves," replied the girl.

Zeb drew back with a shiver.

"I wouldn't dare try," he said.

"Maybe Jim will go," continued Dorothy, looking at the horse.