to who killed the lady," Vance assured him. "But if you are ever to find the murderer, you must look for a shrewd, superior man with nerves of iron, who was in imminent danger of being irremediably ruined by the girl—a man of inherent cruelty and vindictiveness; a supreme egoist; a fatalist more or less; and—I'm inclined to believe—something of a madman."
"Mad!"
"Oh, not a lunatic—just a madman, a perfectly normal, logical, calculating madman—same as you and I and Van here. Only, our hobbies are harmless, d' ye see. This chap's mania is outside your preposterously revered law. That's why you're after him. If his aberration were stamp-collecting, or golf, you wouldn't give him a second thought. But his perfectly rational penchant for eliminating déclassées ladies who bothered him, fills you with horror: it's not your hobby. Consequently, you have a hot yearning to flay him alive."
"I'll admit," said Markham coolly, "that a homicidal mania is my idea of madness."
"But he didn't have a homicidal mania, Markham old thing. You miss all the fine distinctions in psychology. This man was annoyed by a certain person, and set to work, masterfully and reasonably, to do away with the source of his annoyance. And he did it with surpassin' cleverness. To be sure, his act was a bit grisly. But when, if ever, you get your hands on him, you'll be amazed to find how normal he is. And able, too—oh, able no end."
Again Markham lapsed into a long thoughtful silence. At last he spoke.
