Free Spy and the Thief by Edward D. Hoch Page A

“That about does it,” he said.
    “Yes.” Peter started to follow him out of the office, but then he hung back to light a cigarette. His years in the more undercover fields of espionage were hard to shake off, and that piece of carbon paper was almost shouting at him. Instinctively and as a professional he bent and snatched it from the basket.
    Back in London two days later, Peter Smith sat lounging in the comfortable office chair opposite Rand’s cluttered desk in the Department of Concealed Communications. “Well, I brought back the Lavender Machine. But something’s been bothering me.”
    Rand lit one of the American cigarettes he was partial to and turned from the window. “What would that be? I’ve approved your travel expenses.”
    “It’s the American project manager, a fellow named Sine. There’s something peculiar about his entire operation.”
    “Peculiar?” Rand was interested now. He’d always respected Peter Smith’s judgment.
    “Well, I guess I’d have to know a bit about the machine—that is, if it’s not classified, sir.” Rand frowned at the “sir.” He was twelve years younger than Smith and had never got used to all that respect from a man who should have been above him on the ladder.
    “Exactly what do you need to know, Peter?” he asked.
    “If the other side had a Lavender Machine, what it would mean to us.”
    Rand went back to the window, staring out at the exposed banks of the Thames at low tide. “You know most of it already. The Lavender Machine could be described as an outgrowth of the famous Japanese Purple Machine of World War II, but actually it is much closer in concept to the American SIGABA, the German ENIGMA, and our own TYPEX. In fact, the Lavender is said by its inventors to combine the best features of all these previous machines. The Japanese Purple—like their earlier Orange and Red Machines—was basically an alphabetical typewriter using coding wheels of a fairly simple sort. The Americans had actually solved the Purple system more than a year before Pearl Harbor, but they failed to realize the full significance of those vital pre-attack messages.”
    “I know that part of it.” Peter Smith said. “I was more interested in the other side’s operation of the machine, sir, and how that would affect us.”
    Rand nodded and continued. “The. Lavender is a rotor machine. With a knowledge of the Lavender rotors—of their wiring, specifically—and with an actual working machine to guide them, enemy cryptanalysts could determine which rotors in the set were being used for any given message, and what the initial setting was. It would be trial-and-error, a bit plodding, but it could be done if they had a machine.”
    “Couldn’t the manufacturer issue new rotors for all outstanding machines?” Peter Smith asked.
    “Certainly, and that’s what would be done. But all past messages would be compromised, and the future ones would be safe only if immediate action was taken.”
    “Suppose we didn’t know the enemy had a machine?”
    Rand lit another cigarette. “You’re trying to tell me something, Peter, get to the point.”
    Peter smoothed the crumpled piece of carbon paper on the desk between them. “Since the sale and export of Lavender Machines is strictly controlled by the United States government, an export permit must be signed for each one. The permit for the machine we just purchased was signed in the presence of Mr. Sine and myself. But after the government man left, I noticed Sine disposing of a piece of carbon paper. I picked it out of the wastebasket, and found the government man’s signature on it.”
    “So?”
    “There was only one export document to be signed, without copies, so what was the duplicate signature needed for?”
    “I see what you mean,” Rand said, speaking slowly. “You believe Sine is using the duplicate signature to forge an export document for a Lavender Machine—a machine which would find its way into enemy