Free And Be a Villain by Rex Stout

annoying her. I made another try later, on the phone again, but four words was as far as I got. Now it’s no use. This is the third time I’ve flopped on you in ten years, and that’s too often. I don’t want you to pay me, not even expenses.”
    “Nonsense.” Wolfe never gets riled with Saul. “You can give me the details later, if there are any I should have. Will you reach New York in time to come to the office at six o’clock?”
    “Yes.”
    “Good. Do that.”
    Wolfe resumed with Traub. As I have already mentioned, the climax of that two hours’ hard work was when Traub confessed that he frequently bet on horse races. As soon as he had gone Wolfe and I went to the dining room for the lunch previously described, corn fritters with autumn honey, sausages, and a bowl of salad. Of course what added to his misery was the fact that Savarese was expected at two o’clock, because he likes to have the duration of a meal determined solely by the inclination of him and the meal, not by some extraneous phenomenon like the sound of a doorbell.
    But the bell rang right on the dot.

Chapter 8
    Y OU HAVE HEARD OF the exception that proves the rule. Professor F. O. Savarese was it.
    The accepted rule is that an Italian is dark and, if not actually a runt, at least not tall; that a professor is dry and pedantic, with eye trouble; and that a mathematician really lives in the stratosphere and is here just visiting relatives. Well, Savarese was an Italian-American professor of mathematics, but he was big and blond and buoyant, two inches taller than me, and he came breezing in like a March morning wind.
    He spent the first twenty minutes telling Wolfe and me how fascinating and practical it would be to work out a set of mathematical formulas that could be used in the detective business. His favorite branch of mathematics, he said, was the one that dealt with the objective numerical measurement of probability. Very well. What was any detective work, any kind at all, but the objective measurement of probability? All he proposed to do was to add the word numerical , not as a substitute or replacement, but as an ally and reinforcement.
    “I’ll show you what I mean,” he offered. “May I have paper and pencil?”
    He had bounded over to me before I could even uncross my legs, took the pad and pencil I handed him, and bounded back to the red leather chair. When the pencil had jitterbugged on the pad for half a minute he tore off the top sheet and slid it across the desk to Wolfe, then went to work on the next sheet and in a moment tore that off and leaped to me with it.
    “You should each have one,” he said, “so you can follow me.”
    I wouldn’t try to pretend I could put it down from memory, but I still have both of those sheets, in the folder marked ORCHARD , and this is what is on them:
     

     
    “That,” Savarese said, his whole face smiling with eager interest and friendliness and desire to help, “is the second approximation of the normal law of error, sometimes called the generalized law of error. Let’s apply it to the simplest kind of detective problem, say the question which one of three servants in a house stole a diamond ring from a locked drawer. I should explain that X is the deviation from the mean, D is the standard deviation, k is—”
    “Please!” Wolfe had to make it next door to a bellow, and did. “What are you trying to do, change the subject?”
    “No.” Savarese looked surprised and a little hurt. “Am I? What was the subject?”
    “The death of Mr. Cyril Orchard and your connection with it.”
    “Oh. Of course.” He smiled apologetically and spread his hands, palms up. “Perhaps later? It is one of my favorite ideas, the application of the mathematical laws of probability and error to detective problems, and a chance to discuss it with you is a golden opportunity.”
    “Another time. Meanwhile”—Wolfe tapped the generalized law of error with a finger tip—”I’ll keep this.