prime numbahs, Daddy.’ And Daddy, he say right back, ‘They ain’t. But you can catch em, Odetta, if you have a net.’ He called it The Net of Eratosthenes. Take me over to dat box on the wall, Roland—I’m goan answer dat honkey computer’s riddle. I’m goan th’ow you a net and catch you a train-ride.”
Roland took her over, closely followed by Eddie, Jake, and Oy.
“Gimme dat piece o’ cha’coal you keep in yo’ poke.”
He rummaged and brought out a short stub of blackened stick. Detta took it and peered at the diamond-shaped grid of numbers. “Ain’t zackly de way Daddy showed me, but I reckon it comes to de same,” she said after a moment. “Prime numbah be like me—ornery and forspecial. It gotta be a numbah don’t nevvah divide even ’ceptin by one and its own-self. Two is prime, ’cause you can divide it by one an’ two, but it’s the only even numbah that’s prime. You c’n take out all the res’ dat’s even.”
“I’m lost,” Eddie said.
“That’s ’cause you just a stupid white boy,” Detta said, but not unkindly. She looked closely at the diamond shape a moment longer, then quickly began to touch the tip of the charcoal to all the even-numbered pads, leaving small black smudges on them.
“Three’s prime, but no product you git by multiplyin three can be prime,” she said, and now Roland heard an odd but wonderful thing: Detta was fading out of the woman’s voice; she was being replaced not by Odetta Holmes but by Susannah Dean. He would not have to bring her out of this trance; she was coming out of it on her own, quite naturally.
Susannah began using her charcoal to touch the multiples of three which were left now that the even numbers had been eliminated: nine, fifteen, twenty-one, and so on.
“Same with five and seven,” she murmured, and suddenly she was awake and all Susannah Dean again. “You just have to mark the odd ones like twenty-five that haven’t been crossed out already.” The diamond shape on the control box now looked like this:
“There,” she said tiredly. “What’s left in the net are all the prime numbers between one and one hundred. I’m pretty sure that’s the combination that opens the gate.”
“YOU HAVE ONE MINUTE, MY FRIENDS. YOU ARE PROVING TO BE A GOOD DEAL THICKER THAN I HAD HOPED YOU WOULD BE.”
Eddie ignored Blaine’s voice and threw his arms around Susannah. “Are you back, Suze? Are you awake?”
“Yes. I woke up in the middle of what she was saying, but I let her talk a little longer, anyway. It seemed impolite to interrupt.” She looked at Roland. “What do you say? Want to go for it?”
“FIFTY SECONDS.”
“Yes. You try the combination, Susannah. It’s your answer.”
She reached out toward the top of the diamond, but Jake put his hand over hers. “No,” he said. “ ‘This pump primes backward.’ Remember?”
She looked startled, then smiled. “That’s right. Clever Blaine . . . and clever Jake, too.”
They watched in silence as she pushed each number in turn, starting with ninety-seven. There was a minute click as each pad locked down. There was no tension-filled pause after she touched the last button; the gate in the center of the barrier immediately began to slide up on its tracks, rattling harshly and showering down flakes of rust from somewhere high above as it went.
“NOT BAD AT ALL,” Blaine said admiringly. “I’M LOOKING FORWARD TO THIS VERY MUCH. MAY I SUGGEST YOU CLIMB ON BOARD QUICKLY? IN FACT, YOU MAY WISH TO RUN. THERE ARE SEVERAL GAS OUTLETS IN THIS AREA.”
4
THREE HUMAN BEINGS (one carrying a fourth on his hip) and one small, furry animal ran through the opening in the barrier and sprinted toward Blaine the Mono. It stood humming in its narrow loading bay, half above the platform and half below it, looking like a giant cartridge—one which had been painted an incongruous shade of pink—lying in the open breech of a high-powered rifle. In the vastness of the Cradle, Roland and the others looked like mere moving specks. Above them, flocks of pigeons— now with only forty seconds to live—swooped and swirled beneath the Cradle’s ancient roof. As the travellers approached the mono, a curved section of its pink hull slid up, revealing a doorway. Beyond it was thick, pale blue carpeting.
“Welcome to Blaine,” a soothing voice said as they pelted aboard. They all recognized that voice; it was a slightly louder, slightly more confident version of Little