They were seated smoking in Sir John's library after a particularly early breakfast.
"I always said it was the work of a madman," said the inspector in self-defence.
"Callice is no more mad than I am," snapped Sir John. "I wish I were going to try him," he added grimly. "The scoundrel! To think——" His indignation choked him.
"He is not mad in the accepted sense," said Malcolm Sage as he sucked meditatively at his pipe. "I should say that it is a case of race-memory."
"Race-memory! Dammit! what's that?" Sir John Hackblock snapped out the words in his best parade-ground manner. He was more purple than ever about the jowl, and it was obvious that he was prepared to disagree with everyone and everything. As Lady Hackblock and her domestics would have recognised without difficulty, Sir John was angry.
"How the devil did you spot the brute?" he demanded, as Malcolm Sage did not reply immediately.
"Race-memory," he remarked, ignoring the question, "is to man what instinct is to animals; it defies analysis or explanation."
Sir John stared; but it was Inspector Wensdale who spoke.
"But how did you manage to fix the date, Mr. Sage?" he enquired.
"By the previous outrages," was the reply.