The Alchemist's Code (10 page)

V
asco took his absurd mission seriously and proceeded to demonstrate how efficient he was, requisitioning a couple of night guards to escort us out to the Molo and see us safely aboard the gondola. He was the last to board and the first off at Ca' Barbolano, where he would not let the rest of us disembark until Luigi had opened the door and confirmed that all was well within. Nor would he let Bruno carry the Maestro upstairs before Giorgio and I had finished bringing in the oar and cushions for overnight storage in the
androne
and the door had been locked and bolted. Then he shepherded us up the stairs, made sure the apartment was properly secured after we entered, and ordered Giorgio to inspect his family's quarters in the attic and report any intruders. I smirked and he sneered.

The Maestro had endured this exhibition with astonishing self-control. Now back on his own feet, he wanted to get to work. “The bag, please.”

“Not until I am finished securing the house, Doctor.”

“If you are looking for ghouls, Filiberto,” I said, “then you should begin over here. This is our only guest room, so you must either share the bed with the resident ghoul or sleep out here on a couch.”

The
vizio
bared his teeth like a dog. “Who's in there?”

“
Sier
Danese Dolfin, about to become son-in-law to
messer
Counselor Sanudo. Evict him if you wish. We have had very little success.”

Vasco faced a tricky decision, whether or not to intrude on a nobleman and near relation to a ducal counselor in a nobleman's house, but he rose to the challenge. After a brief glance at the Maestro, who remained studiously blank, he took up a lamp and marched into the spare room. Unfortunately I did not witness the expression on our guest's face when the dreaded
Missier Grande
's deputy appeared like an apocalyptic nightmare and demanded to know who he was and what he was doing there. Vasco was smirking a little when he came out. He locked the door behind him and I would really have enjoyed seeing Danese's reaction to that, too.

The
vizio
inspected the bedrooms with special care—mine, the Maestro's, Bruno's—peering in wardrobes and under beds. He went over the kitchen, the dining room, and started in on the
salone
, confirming that no assassins or demons crouched behind the statues. By then the Maestro and I were in the atelier, I lighting lamps for an all-night session, and he at his desk with a great leather-bound manuscript of Johannes Trithemius's
Steganographia
.

He looked up angrily as Vasco entered and began snooping around, peering at everything: terrestrial globe, celestial globe, armillary sphere, alchemy bench, reagent shelves, wall of books. The alcove in the center of the books contains a huge oval mirror framed by overweight cherubs. Vasco studied it for a moment, took another moment to locate the hidden catch, then slid the bolt and pushed on the frame. The whole back of the alcove turned on its pivot. There was enough light on the far side for him to recognize the dining room he had seen earlier. He nodded as if satisfied, closed the door again, and bolted it.

Only then did he deign to deliver the precious satchel to the Maestro, who opened it without a word and began going through its contents like a child at Christmas. Vasco settled himself in one of the green chairs, where he could watch. I took the red one facing him, confident I would not be left in peace for long.

“You really think those papers are of any true value?” I inquired. I knew that the entire Turkish army could march through the room without distracting the Maestro from whatever he was doing.

Vasco glanced at him, came to the same conclusion, and answered, “Worth killing for, easily.”

I shook my head. “
Circospetto
would never have parted with them without keeping a copy. What he would love to do, of course, is catch Algol and then use his cipher to send false information to Constantinople.”

“How do you know that Algol is spying for the Porte?”

“I don't,” I admitted. “He could be working for the Vatican, the Louvre, the Escorial, or even Whitehall. All states play the same sort of game. I just happen to have a grudge against the Turks. Perhaps the reason Venice can't break the cipher is that its man in the Porte has been taken or turned and the writing on those papers is pure canal mud, meant to tantalize the Ten into insanity.”

Vasco shrugged. “You'll go mad thinking that way.”

“Or
Circospetto
made it all up by himself to bait his trap for Algol.”

“I wouldn't put that past him. You're an expert in code breaking as well as everything else, I suppose?”

“Not
everything
else.”

He scowled at the fireplace for a moment, then asked in a bored tone, “So what's a Caesar, that you mentioned earlier?”

“The cipher Julius used. You shift every letter a known number of places along the alphabet. Instead of
A
you write, say,
C
, and instead of
D
you write
F
. It's easy to break, because in any language some letters are used much more often than others. In
Veneziano
, for instance,
E
and
A
are about the busiest and they're close together in the alphabet, so if your ciphertext shows a lot of, say,
M
's and
Q
's, you assume those are
A
and
E
. Also
R
,
S
, and
T
are used a lot and fall next to each other, so they'll stand out as a group. It would be easier if everybody spelled words the same way, and it depends a little on whether your spy has ignored accents or not, but that's the principle. Once you have pinned down a few letters, the rest follow automatically, as was shown by Leon Battista Alberti of Florence in—”

“But shown much earlier,” said the Maestro, “by Abu Yusuf Ya'qub ibn Is-haq ibn as-Sabbah ibn 'omran ibn Ismail al-Kindi. Ninth century, in fact. Come over here and make yourself useful. You, too,
Vizio
.”

We rose and went like good little schoolboys.

“Every one of the sheets,” the Maestro said, “has ten five-letter words in a row, and no more than thirty-two rows on a page. This may be steganography, where the text is hidden in full view. You may have to take the first letter of the fourth word and the third of the one below and so on, or it may even require a Cardan grille to identify the meaningful letters. Let us hope that the original was copied exactly. But it wouldn't be, of course. The spacing between lines varies, see? And we can't tell whether it did in the original or not. I want you each to take a pen and a sheet of paper and invent a page just like these, 320 nonsense words in 10 columns. Go to it.”

Vasco was frowning, but I suppose it seemed a better alternative than total boredom, so he accepted a pen and an inkwell, and went over to work on the slate-topped table with the crystal ball. I sat at my side of the desk and rapidly discovered that the job was not as easy as it seemed. When we turned in our assignments, the Maestro studied them while we peered over his shoulders.

Then he chuckled. “You have disproved your own hypothesis, Alfeo! You see where you both went wrong?”

Fortunately I did. “We weren't repeating ourselves,” I said. “I never wrote a double letter, but the originals have lots of them. There's even three
K
's in a row there. I never began a word with the same letter I'd used to start the one before. And we never wrote a real word. Algol has a
MOLO
and even
PASTA
if you ignore the space in the middle.”

“And so on,” the Maestro said sourly, annoyed that I had spoiled his revelation. “You were too random! Your lack of order is a sort of order in itself. That means that these originals were not made by someone just writing random letters. There is meaning in them. Now all we have to do is pull it out.”

“How can you do that if you don't know what language it is?” Vasco demanded.

“Not many languages are likely—Tuscan, Latin, Spanish,
Veneziano
, Arabic, Turkish, French. They use Old Persian in the Porte sometimes. I can read most of those and recognize the rest. But perhaps I can find another way. Take this trash away,
Vizio
.” The old man heaved himself to his feet, I handed him his staff, and he hobbled over to the crystal. “You can both get some sleep. I'll lock up, Alfeo.”

I doused the other lamps and shooed Vasco out of the atelier ahead of me.

I did not offer to share my bed with him, but I did find him a blanket and a pillow. He stretched out on a couch in the
salone
.

The last thing I did before going to bed was to consult my tarot. It gave me an assortment of the minor arcana, all low numbers without a single court card or trump. I had not seen such a disgusting heap since before I was toilet trained. Deciding I must be overtired, I fell into bed.

I
awoke at dawn as always. Remembering the work I had to do, I growled myself upright, groaned myself into my clothes, and grouched out into the
salone
in my stocking soles. The
vizio
's blanket lay unoccupied beside the couch, so he had presumably gone to recharge the canal, and I had a chance to reach the atelier without attracting his unwelcome attention.

The atelier door is both locked and warded at night. The Maestro might have omitted setting the wards if he was exhausted after his clairvoyance, but I played safe and cast the counter-spell before using my key. As soon as I had let daylight in, I went to inspect the slate-topped table.

What I found was ominous. It began in the usual barely legible scrawl:

But that was followed by mere chalk scribbles, snail tracks bearing no resemblance to writing at all. I have known the Maestro to prophecy in such appalling cacography that neither of us could read half of it, but I could recall no occasion when he had failed to produce a reasonable attempt at a quatrain.

And my tarot had failed me.

The door closed behind me and I spun around angrily. It was not, as I had expected, Filiberto Vasco snooping. It was Danese Dolfin, obviously released from his kennel and apparently not snooping, because he came striding straight over to me, his manner all but shooting lightning bolts. He had given up wearing his sling.

“Why is the
vizio
here?” he demanded.

“I can't tell you.”

“You don't know?”

“I know, but I can't tell you.”

That stopped him. I was tempted to suggest he ask around his new family, but even that hint would violate my oath.

“Does
sier
Alvise Barbolano know he's here?”

“No,” I said, “and I strongly advise you not to tell him.” Then I remembered old Luigi, whose mouth is larger than the Adriatic. The news would be out the moment Luigi could find a listener.

More wary now, Danese said, “Is he going to stay long?”

There were witty retorts I could have made to that, but I wasn't feeling witty. “Several days.”

“It's intolerable!” Danese shouted, turning on his heel.

“Yes,” I said softly as he disappeared. Life holds many trials we can do nothing about, but with luck Vasco would rid us of one of them.

I followed Danese out, locked the atelier, and went in search of shaving water. Halfway along my trek to the kitchen stood Vasco, folding his blanket with the satchel strap over his shoulder like a tippet, as if he had worn it all night. We greeted each other with cold nods, acknowledging that our enforced cooperation was only temporary and battle would resume at the first opportunity.

The kitchen was redolent with ambrosial scents of fresh bread and the
khave
Mama Angeli was just preparing. Giorgio and four sons sat gobbling at the big table—the older girls would still be dressing small fry. We exchanged blessings and they waited hopefully for me to explain the additional houseguest. I just asked them to keep down the noise outside the Maestro's room.

In stalked the
vizio
wearing sword and satchel, closely followed by Danese wearing his lute. They both looked rumpled and unshaven—Danese less so, because he was blond and had not had to sleep in his clothes—and their joint arrival seemed so staged that I half expected them to burst into song.

Vasco asked me, “When will Nostradamus want to see these papers again?”

“Probably not for a couple of hours.”

“May I ask your gondolier to take me home to fetch some clothes? I won't be long.” He couldn't resist adding, “Just promise me you'll keep the door locked while I'm gone.”

“Should I wear my sword?”

“You're probably safer without it.”

“Very true,” I said, “I hate inquests.” I glanced inquiringly at Giorgio and he nodded, of course. “He will be happy to oblige you,
lustrissimo
.” I was sorely tempted to add, “But don't tip him too generously; he isn't used to it.” I didn't say that, though, and the self-restraint required must have made all the angels in Heaven cheer.

Danese said nothing, but when gondolier and
vizio
departed, he went with them. I looked across the table at the amused stare of a descending line of dark eyes—Christoforo, Corrado, Archangelo, and little Piero.

“It's a good job I like your father,” I said. “Or I'd be praying for sharks to sink his gondola. Chris, go and bolt the front door behind them.”

Eight eyes widened. “Why?” chorused one bass, one baritone, one tenor, and one alto.

“You know the doge is a great book collector and the Maestro is an expert on old books? He's examining some very rare documents for the doge, so valuable that the doge sent the
vizio
along to guard them.” That was as close to the truth as I could come and it satisfied the youngsters, although probably not Mama, who never missed a word of any conversation, spoken or unspoken. Hating myself for even that much deception, I beat a fast retreat with a mug of hot water and another of
khave
.

I checked that
both
doors were bolted as well as locked.

As soon as I had shaved, I took my tarot deck from under my pillow and tried another reading. It was no more informative than the last one and I tucked the deck away again, fearing that any more attempts to force it might desensitize it. My tarot skill had apparently become as useless as the Maestro's clairvoyance, which confirmed what I already suspected—that whatever we were up against would not be deterred by bolted doors or Filiberto Vasco's sword.

 

When Vasco returned, he found me at my side of the big desk behind a pile of every book on cryptography in the Maestro's library—Roger Bacon, Johannes Trithemius, Girolamo Cardano, Leon Battista Alberti, Giovani Porta, Blaise de Vigenère. Al-Kindi was there, too, but I can't read Arabic. Needless to say, I had made small progress with those I could read.

“No sign of the Maestro,” I said. “May I have a look at the evidence?” You cannot conceive how much it hurt me to sound humble.

The
vizio
could, though, and smirked. “What for?”

“Not the ciphertext, just
Circospetto
's notes.”

He had the effrontery to make himself comfortable in the Maestro's chair and beam across at me. “Why?”

“I have an idea and I wanted to see if the Ten's gnomes thought to check for it.”

“What sort of idea?”

“About nomenclators.”

“What's a nomenclator?”

“This frantic impulse to exercise your brain after so many years of disuse may do serious damage.”

He just smiled.

“I taught you last night,” I said with saintly patience, while silently vowing epochal revenge, “that a simple Caesar alphabet cipher is too easy to break. The most popular way to improve it is to add more symbols, usually numbers. So you have, say,
32
standing for
D
,
14
for
N
, and a dozen or so different codes for a very common letter like
E
—and so on. Then you start adding symbols for common words, perhaps
42
for
the
and
51
for
and
. That sort of list is called a
nomenclator
. It makes the cipher harder to break, but not much. Carry it too far and you're writing a whole codebook, with numbers for
King of Denmark
,
Venice
,
Janissary regiment
, and Lord knows what. That's more secure, but then your spy can't carry the cipher in his head anymore and has to lug a book around with him. If the enemy captures it, a codebook is enough evidence to hang him and reveal all your coded correspondence, past, present, and future. If a Caesar alphabet is compromised, you only have to change the key, which is a single number, whereas replacing a codebook is a huge task. But codebooks are how most states encipher their dispatches.”

Vasco nodded as if he understood. He does have a certain low animal cunning. “Algol doesn't use numbers.”

“No, he uses twenty-three letters, and if he is pairing them up he has hundreds of couplets available. So the first thing the Maestro asked was if Sciara's gnomes had checked for couplet frequency. Perhaps
GX
stands for
A, NT
for
B, EO
for
King of France
, understand? Now you pass me the notes and I'll tell you what to look for in the ciphertext and if we're quick about it we may have this thing broken before the Maestro comes.”

“And if we're really lucky, angels may appear to transport you to Paradise.”

I thought that was the end and the pleasure of refusing me had overridden his duty, but then he shrugged and opened the satchel. He held out the work notes, making me stand up to reach them.

“So what do I look for?” he asked.

“My initials.
LAZ
, for Luca Alfeo Zeno. How many times can you see those letters together? I know they appear more often than they should.” I set to work reading what Sciara's team had tried, ignoring more scoffing from Vasco.

Sciara's notes were thorough and detailed. I learned that the ciphertext comprised four Algol dispatches, varying in length from three pages to nine, twenty-four pages in all. The Ten's cryptologists had tested for letter frequency and couplet frequency and even “word” frequency, although the five-letter groups could not be real words. Their conclusion was that the distribution of letters was not truly random, but not skewed enough for a substitution cipher, such as a Caesar, or a transposition cipher, which is a gigantic anagram. They suspected that all four dispatches had been written using the same code, so very likely it was a nomenclator.

They had not tested for triplets, though. Of course my own initials in a page of meaningless text will always jump out at me, and the previous evening I had seen them twice on one page when I was looking over the Maestro's shoulder. After a few minutes of angry muttering, Vasco announced that he had found my initials seven times, and at least once in each of the four dispatches. We had grasped a thread in the labyrinth! That ought to lead somewhere.

But where? There were thousands of other three-letter combinations to look for, and the only sensible next move I could think of was to hand the problem back to Sciara and tell him to put his legions to work on triplet frequencies. I suggested we each try to find another repeating triplet.

Eventually the thump of the Maestro's staff on the terrazzo outside announced his approach and Vasco hastily vacated his chair. The old man came hobbling in, looking murderous.

“Make any sense of it?” he growled at me, with a wave at the slate table.

“Nine words,” I said. “That's all.”

He grunted, meaning that he had reached the same conclusion.

“And my tarot doesn't work either.”

He seemed unsurprised. “Why do you think he's called Algol?
Vizio
, who named the unknown that and why?”

“I have no idea, Doctor.”

More grunt.

I doubted that Algol would turn out to be a true ghoul, a monster that haunts graveyards and eats corpses, but he might well be a demonologist, and the laws of demonology dictate that anyone who employs demons will soon find that the shoe is on the other hoof and the demons are employing him.

Vasco was looking puzzled. I thought it kinder to leave him that way.

“Can you break a nomenclator in an unknown language?” I asked.

The Maestro's scowl darkened. “Given time and enough text to work on, yes. But there are far more good ciphers than good people using them. When a cipher is broken, it is almost always because the operator was careless. Human error damns us all! If we look hard enough and long enough, we will find that he has made a mistake somewhere.”

That was my cue. “He likes my initials. He used them seven times.”

The effect on the Maestro was dramatic. He sat up straight and his eyes blazed with excitement. “Where? Show me!”

 

Two minutes later he snapped, “Bring me the pastels!”

I fetched our box of pastels.

 

We marked every
LAZ
in red. After another ten minutes or so we had located and highlighted four more triplets that were repeated at least once. Nostradamus told me to round up the three oldest Angeli children currently available. Reading and writing are uncommon skills among the citizen class, but I taught Mama and she teaches all her children.