"See what kind it is, Lou—if you can," she advised.

"Can't very well," replied the other, attempting to lean out and peer through her glasses. But it was too far away to identify.

"Hope it's not a thief or anybody like that," remarked Linda, recalling the other time a plane had followed them, in order that the pilot might steal Kitty Clavering's necklace.

"Don't worry!" returned Louise. "We haven't anything like pearls with us today!"

"You have your earrings! And besides, we must have a couple of hundred dollars between us."

But the plane had disappeared again, and the girls gave their attention to the country beneath them, flying low enough to watch the children on their sleds, and the skaters on the frozen lakes. The winter sports looked so inviting that both Linda and Louise wished they could stop and join in.

"Maybe we can do that tonight," exclaimed Louise. "If we get back to Montreal safely."

"Aunt Emily wouldn't approve," Linda reminded her.

"Your Aunt Emily doesn't approve of any of this! But anyway, it's all in a good cause."

"And we've gotten along fine so far...."