THE elevator-man in the office building remembered Garth and grinned delightedly. Joan had thought him a dismal-looking person when they came in, but the smile greatly changed his tired, uninteresting face.

"Still livin’ on the lighthouse?" he inquired genially. "Wisht I could!" He clanged the elevator door open. "Always does me good, seein’ that feller," he remarked to Joan; "wisht he came oftener."

They were five minutes late, but there was no sign of Dr. Stone.

"You always have to wait ages," said Garth; "so we might as well do something. Let's play The Miraculous Memory-Stretcher."

"May I ask what that is?" Joan said.

"That's what Fogger calls it. You show a person a picture in a magazine or something for about two flashes, and then snatch it away again, and they have to say all the things that