Hawkes took a coin from his pocket and dropped it in a slot at the side of the board. It lit up. A crazy, shifting pattern of colored lights passed over it, restless, never pausing. "What happens now?" "You set up a mathematical pattern with these keys," Hawkes said, pointing to a row of enamelled studs along the side of the machine. "Then the lights start flashing, and as soon as they flash--at random, of course--into the pattern you've previously set up, you're the winner. The skill of the game comes in predicting the kind of pattern that will be the winning one. You've got to keep listening to the numbers that the croupier calls off, and fit them into your sequence." Suddenly a bell rang loudly, and the board went dead. Alan looked around and saw that all the other boards in the hall were dark as well. The man on the rostrum in the center of the hall cleared his throat and sang out, "Table 403 hits us for a hundred! 403! One hundred!" A pasty-faced bald man at a table near theirs rose with a broad grin on his face and went forward to collect. Hawkes rapped sharply on the side of the table to get Alan's attention. "Look here, now. You have to get a head start. As soon as the boards light up again, I have to begin setting up my pattern. I'm competing against everyone else here, you see. And the quickest man wins, usually. Of course, blind luck sometimes brings you a winner--but not very often." Alan nodded and watched carefully as Hawkes' fingers flew nimbly over the controlling studs the instant the tables lit for the next round. The others nearby were busy doing the same thing, but few of them set about it with the air of cocky jauntiness that Hawkes wore. Finally he stared at the board in satisfaction and sat back. The croupier pounded three times with a little gavel and said, "103 sub-prime 5." Hastily Hawkes made a correction in his equation. The lights on the board flickered and faded, moving faster than Alan could see. "377 third-quadrant 7." Again a correction. Hawkes sat transfixed, staring intently at the board. The other players were similarly entranced, Alan saw. He realized it was possible for someone to become virtually hypnotized by the game, to spend days on end sitting before the board. He forced himself to follow Hawkes' computations as number after number was called off. He began to see the logical pattern of the game. It was a little like astrogation, in which he had had the required preliminary instruction. When you worked out a ship's course, you had to keep altering it to allow for course deflection, effects of planetary magnetic fields, meteor swarms, and such obstacles--and you had to be one jump ahead of the obstacles all the time.