Caswell thanked him, lifted the Regenerator in both arms and hurried out.

After figuring his commission, the clerk smiled to himself and lighted a cigarette. His enjoyment was spoiled when the manager, a large man impressively equipped with pince-nez, marched out of his office.

"Haskins," the manager said, "I thought I asked you to rid yourself of that filthy habit."

"Yes, Mr. Follansby, sorry, sir," Haskins apologized, snubbing out the cigarette. "I'll use the display Denicotinizer at once. Made rather a good sale, Mr. Follansby. One of the big Rex Regenerators."

"Really?" said the manager, impressed. "It isn't often we—wait a minute!

You didn't sell the floor model, did you?"

"Why—why, I'm afraid I did, Mr. Follansby. The customer was in such a terrible hurry. Was there any reason—"

Mr. Follansby gripped his prominent white forehead in both hands, as though he wished to rip it off. "Haskins, I told you. I must have told you! That display Regenerator was a Martian model. For giving mechanotherapy to Martians."

"Oh," Haskins said. He thought for a moment. "Oh."

Mr. Follansby stared at his clerk in grim silence.

"But does it really matter?" Haskins asked quickly. "Surely the machine won't discriminate. I should think it would treat a homicidal tendency even if the patient were not a Martian."

"The Martian race has never had the slightest tendency toward homicide.

A Martian Regenerator doesn't even process the concept. Of course the

Regenerator will treat him. It has to. But what will it treat?"

"Oh," said Haskins.

"That poor devil must be stopped before—you say he was homicidal? I don't know what will happen! Quick, what is his address?"