Джек Макдевитт - Cryptic - The Best Short Fiction of Jack McDevitt

It was, on the whole, depressing reading. In his conclusion, Dickinson argued that truth will not wait on human convenience, that if man cannot adapt to a neutral universe, then that universe will indeed come to seem hostile. We must make do with what we have and accept truth wherever it leads. The modern cathedral is the radiotelescope.

Sandage was involved in the verification procedure for McCue’s work, and for the already controversial Cal Tech equations. All that is another story. What is significant is that it got me thinking about verifications, and I realized I’d overlooked something. There’d been no match for the Procyon readings anywhere in the data banks since the original reception. But the Procyon recordings might themselves have been the confirmation of an earlier signal!

It took five minutes to run the search. There were two hits.

Both were fragments, neither more than fifteen minutes long; but there was enough of each to reduce the probability of error to less than one percent.

The first occurred three weeks prior to the Procyon reception.

The second went back to 2007, a San Augustin observation. Both were at 40 gigahertz. Both had identical pulse patterns. But there was an explosive difference, sedately concealed in the target information line. The 2007 transmission had come while the radiotelescope was locked on Sirius!

When I got back to my office, I was trembling.

Sirius and Procyon were only a few light-years apart. My God, I kept thinking, they exist! And they have interstellar travel!

I spent the balance of the day stumbling around, trying to immerse myself in fuel usage reports and budget projections. But mostly what I did was watch the desert light grow hard in the curtains, and then fade. The two volumes of Edward Gibbon were propped between a Webster’s and some black binders. The books were thirty years old, identical to the set in Chaney’s den. Some of the pages, improperly cut, were still joined at the edges.

I opened the first volume, approximately in the middle, and began to read. Or tried to. But Ed Dickinson kept crowding out the Romans. Finally I gave it up, took the book, and went home.

There was duplicate bridge in town, and I lost myself in that for five hours. Then, in bed, still somewhat dazed, I tried The Decline and Fall again.

It was not the dusty roll call of long-dead emperors that I had expected. The emperors are there, stabbing and throttling and blundering. And occasionally trying to improve things. But the fish-hawkers are there too. And the bureaucrats and the bishops.

It’s a world filled with wine and legionnaires’ sweat, mismanagement, arguments over Jesus, and the inability to transfer power, all played out to the ruthless drumbeat of dissolution. An undefined historical tide, stemmed occasionally by a hero, or a sage, rolls over men and events, washing them toward the sea. (During the later years, I wondered, did Roman kids run down matrons in flashy imported chariots? Were the walls of Damascus defiled by profanity?)

In the end, when the barbarians push at the outer rim of empire, it is only a hollow wreck that crashes down.

Muggeridge had been there.

And Dickinson, the altar boy, amid the fire and waste of the imperial city, must have suffered a second loss of faith.

We had an electrical failure one night. It has nothing to do with this story except that it resulted in my being called in at 4:00 a.m., not to restore the power, which required a good electrician, but to pacify some angry people from New York, and to be able to say, in my report, that I had been on the spot.

These things attended to, I went outside.

At night, the desert is undisturbed by color or motion. It’s a composition of sand, rock, and star; a frieze, a Monet, uncomplicated, unchanging. It’s reassuring, in an age when little else seems stable. The orderly mid-twentieth century universe had long since disintegrated into a plethora of neutron galaxies, colliding black holes, time reversals, and God knows what.

The desert is solid underfoot. Predictable. A reproach to the quantum mechanics that reflect a quicksand cosmos in which physics merges with Plato.

Close on the rim of the sky, guarding their mysteries, Sirius and Procyon, the bright pair, sparkled. The arroyos are dry at that time of year, shadowy ripples in the landscape. The moon was in its second quarter. Beyond the administration building, the parabolas were limned in silver.

My cathedral.

My Stonehenge.

And while I sat, sipping a Coors, and thinking of lost cities and altar boys and frequency counts, I suddenly understood the significance of Chaney’s last remark! Of course Dickinson had not been able to read the transmission. That was the point!

I needed Chaney.

I called him in the morning, and flew out in the afternoon. He met me at Logan, and we drove toward Gloucester. “There’s a good Italian restaurant,” he said. And then, without taking his eyes off the road: “What’s this about?”

I’d brought the second Gibbon volume with me, and I held it up for him to see. He blinked.

It was early evening, cold, wet, with the smell of approaching winter. Freezing rain pelted the windshield. The sky was gray, heavy, sagging into the city.

“Before I answer any questions, Hutch, I’d like to ask a couple. What can you tell me about military cryptography?”

He grinned. “Not much. The little I do know is probably classified.” A tractor-trailer lumbered past, straining, spraying water across the windows. “What, specifically, are you interested in?”

“How complex are the Navy’s codes? I know they’re nothing like cryptograms, but what sort of general structure do they have?”

“First off, Harry, they’re not codes. Monoalphabetic systems are codes. Like the cryptograms you mentioned. The letter ‘G’ always turns up, say, as an ‘M’. But in military and diplomatic cryptography, the ‘G’ will be a different character every time it appears. And the encryption alphabet isn’t usually limited to letters; we use numbers, dollar signs, ampersands, even spaces.” We splashed onto a ramp and joined the Interstate. It was elevated and we looked across rows of bleak rooftops. “Even the shape of individual words is concealed.”

“How?”

“By encrypting the spaces.”

I knew the answer to the next question before I asked it. “If the encryption alphabet is absolutely random, which I assume it would have to be, the frequency count would be flat. Right?”

“Yes. Given sufficient traffic, it would have to be.”

“One more thing, Hutch. A sudden increase in traffic will alert anyone listening that something is happening even if he can’t read the text. How do you hide that?”

“Easy. We transmit a continuous signal, twenty-four hours a day. Sometimes it’s traffic, sometimes it’s garbage. But you can’t tell the difference.”

God have mercy on us, I thought. Poor Dickinson.

We sat at a small corner table well away from the main dining area. I shivered in wet shoes and a damp sweater. A small candle guttered cheerfully in front of us.

“Are we still talking about Procyon?” he asked.

I nodded. “The same pattern was received twice, three years apart, prior to the Procyon reception.”

“But that’s not possible.” Chaney leaned forward intently. “The computer would have matched them automatically. We’d have known.”

“I don’t think so.” Half a dozen prosperous, overweight men in topcoats had pushed in and were jostling each other in the small entry. “The two hits were on different targets. They would have looked like an echo.”

Chaney reached across the table and gripped my wrist, knocking over a cup. “Son of a bitch,” he said. “Are you suggesting somebody’s moving around out there?”