“I see—the trail of the serpent....”

“Don’t make comments until I have finished,” retorted Duncan, ruffled by Potter’s manner.

“I beg your pardon,” good-naturedly. “Go ahead.”

But it was some moments before Duncan complied with the request.

“I have come to you with my problem,” he began finally, “because I have an idea it may be in your province.”

“Ah. Under what heading?”

“Kleptomania.”

Potter elevated his eyebrows. “It is a recognized mental derangement,” he conceded.

“Curable?”

“Doubtful.” Potter forebore to look at Duncan; instinctively he knew the hope his friend was pinning on him and his advice. “Has Miss Langdon ever had scarlet fever?”