Thursby stood up. "If the Court please, I would like to stage a small demonstration for the members of the jury." The Court gave permission, and a roulette wheel was hauled in on a small table. I watched with interest and without objection while Thursby demonstrated the use of the gadget and then asked each of the jurors in turn to try it. It was a long way from being a successful demonstration. Some of the jurors didn't hold the thing right, and some of those that did just didn't have the mental ability required to use it. But that didn't bother Thursby. "Your Honor, and Gentlemen of the Jury," he said, "you are all aware that a device constructed for the purpose of cheating at any gambling game is not necessarily one hundred per cent infallible. It doesn't have to be. All it has to do is turn the odds in favor of the user. "You are all familiar with loaded dice, I'm sure. And you know that loading dice for one set of numbers merely increases the probability that those numbers will come up; it does not guarantee that they will come up every time. "It is the same with marked cards. Marking the backs of a deck of cards doesn't mean that you will invariably get a better hand than your opponent; it doesn't even mean that you will win every hand. "The device taken from the defendant at the Golden Casino does not, as you have seen, work every time. But, as you have also seen, it certainly _does_ shift the odds by a considerable percentage. And that, I submit, is illegal under the laws of this state." He went on, building on that theme for a while, then he turned the trial over to the defense. "Call Dr. Pettigrew to the stand," I said. I heard Thursby's gasp, but I ignored it. A chunky, balding man with a moon face and an irritated expression came up to be sworn in. He was irritated with me for having subpoenaed him, and he showed it. I hoped he wouldn't turn out to be hostile. "You are Dr. Herbert Pettigrew?" I asked. "That is correct." "State your residence, please." "3109 La Jolla Boulevard, Los Angeles, California." "You are called 'Doctor' Pettigrew, I believe. Would you tell the Court what right you have to that title?" He looked a little miffed, but he said: "It is a scholarly title. A Doctorate of Philosophy in physics from Massachusetts Institute of Technology." "I see. Would you mind telling the Court what other academic degrees you have?" He reeled off a list of them, all impressive. "Thank you, doctor," I said. "Now, what is your present occupation?" "I am a Professor of Physics, at the University of California in Los Angeles." I went on questioning him to establish his ability in his field, and by the time I was finished, the jury was pretty well impressed with his status in the scientific brotherhood. And not once did Thursby object. Then I said, "Dr. Pettigrew, I believe you came to this city on a professional matter?" "Yes, I did." He didn't hesitate to answer, so I figured I hadn't got his goat too much.