“Are you seriously suggesting——?” began Markham; but Vance interrupted him.

“Yes! I’m seriously suggesting that the person who killed Cock Robin with an arrow has vented his grim humor upon the hapless Sprigg. Coincidence is out of the question. Such repetitive parallels would knock the entire foundation out from all sanity and reason. ’Pon my soul, the world is mad enough; but such madness would dissipate all science and rational thinking. Sprigg’s death is rather hideous; but it must be faced. And however much you may force yourself to protest against its incredible implications you’ll eventually have to accept them.”

Markham had risen, and was pacing nervously up and down.

“I’ll grant there are inexplicable elements in this new crime.” His combativeness had gone, and his tone had moderated. “But if we assume, even tentatively, that some maniac is at large reconstructing the rhymes of his nursery days, I can’t see how it will help us. It would practically close all routine lines of investigation.”

“I shouldn’t say that, don’t y’ know.” Vance was smoking meditatively. “I’m inclined to think that such an assumption would supply us with a definite basis of inquiry.”

“Sure!” snapped Heath with ponderous sarcasm. “All we gotta do is to go out and find one bug among six million people. A cinch!”

“Don’t let the fumes of discouragement overcome you, Sergeant. Our elusive jester is a rather distinctive entomological specimen. Moreover, we have certain clews as to his exact habitat. . . .”

Markham swung round. “What do you mean by that?”

“Merely that this second crime is related to the first not only psychologically, but geographically. Both murders were committed within a few blocks of each other,—our destructive demon at least has a weakness for the neighborhood in which the Dillard house is situated. Furthermore, the very factors of the two murders preclude the possibility of his having come from afar to give rein to his distorted humor in unfamiliar surroundings. As I learnedly pointed out to you, Robin was translated into the Beyond by some one who knew all the conditions obtaining at the Dillard house at the exact hour the grisly drama was performed; and surely it’s obvious that this second crime could not have been so tidily staged had not the impresario been acquainted with Sprigg’s ambulat’ry intentions this morning. Indeed, the entire mechanism of these weird playlets proves that the operator was intimately cognizant of all the circumstances surrounding his victims.”

The heavy silence that followed was broken by Heath.