"By the devil!" Frederick shouted. "For a year I've been going from one nest of vipers to another! My fine German princes were lambs by comparison and—you know something?—even those treacherous Milanese who caused me so much suffering, at least they faced me in the open field, without trying to stab me in my sleep! What shall we do?"
His son Frederick suggested accepting the invitation. Better to watch out for a single, known enemy than many unknown ones. "He's right, Father," Baudolino said. "You stay in that castle, and my friends and I will represent a barrier around you, so that no one can approach you without passing over our bodies, day or night. We will taste first every substance presented to you. Don't say anything: I'm not a martyr. Everyone will know that we will eat and drink before you, and nobody will consider it wise to poison one of us because then your wrath would be unleashed on every inhabitant of that castle. Your men need rest, Cilicia is inhabited by Christian peoples, the sultan of Iconium no longer has troops to pass the mountains and attack you again, Saladin is still too far off, this region is made up of peaks and crevasses that are excellent natural defenses, it seems to be the ideal land for restoring everyone's strength."
After a day's march in the direction of Seleucia, they entered a gorge that left them barely enough space to follow the course of the river. All of a sudden the gorge opened out, allowing the river to run over a vast flat stretch, before accelerating its course and descending, engulfed by another gorge. Not very far from the shore, sprouting from the plain like a mushroom, rose a tower of irregular lines, standing out, pale blue, before the eyes of those coming from the east, while the sun was setting behind it, so that, at first sight, it was impossible to tell whether the tower was the work of man or of Nature. Only as you neared it could you understand that it was a sort of rocky mass on which a castle was built, from which obviously one could dominate both the plain and the girdle of surrounding mountains.
"There," Ardzrouni said then. "My lord, you may encamp your army in the plain, and I advise you to deploy it over there, below the river, where there is space for the tents, and water for men and animals. My castle is not large, and I suggest you climb up to it only with a group of trusted men."
Frederick instructed his son to deal with the encampment, and to remain with the army. He decided to take with him only about ten men, along with Baudolino and his friends. His son tried to protest, saying he wanted to be near his father, and not a mile away. Once again he looked at Baudolino and his men with scant trust, but the emperor could not be swayed. "I will sleep in that castle," he said. "Tomorrow morning I will bathe in the river, and for that I have no need of you. I will swim to your camp to wish you good day." The son said that his will was law, but reluctantly.
Frederick separated himself from the main body of the army, with his ten armed men, Baudolino, the Poet, Boron, Abdul, Solomon, and Boidi, who was dragging Zosimos on his chain. All were curious to learn how they would climb up to that refuge, but, going around the massif, they discovered finally that to the west the drop was less severe, only a little, but enough to dig into it and carve a stepped path, on which no more than two flanked horses could pass at once. Anyone wishing to ascend with hostile intentions had to climb the broad steps slowly, so just a pair of lone archers, from the battlements of the castle, could wipe out the invaders, two by two.
At the end of the climb a portal opened into a courtyard. From the exterior of that gate the path continued, grazing the walls, and, even narrower, the brink of the cliff, to another, smaller gate, on the north side, then it ended, over the void.
They entered the courtyard, which gave access to the actual castle, its walls bristling with slits, but defended in their turn by the walls that separated the courtyard from the abyss. Frederick deployed his guards on the outer ramparts, so they could survey the path from above. It did not seem that Ardzrouni had men of his own, beyond a few attendants who guarded the various doors and passages. "I don't need an army here," Ardzrouni said, smiling with pride. "I cannot be attacked. And besides, as you, Holy Emperor, will see, this is not a place of war, it is the refuge where I pursue my studies of air, fire, earth, and water. Come, I will show you where you can be lodged in a worthy fashion."
They climbed a great staircase, and at the second turn they entered a spacious salle d'armes, furnished with some benches and with panoplies on the walls. Ardzrouni opened a solid wood door with metal studs, and led Frederick into a sumptuously furnished chamber. There was a bed, with a canopy, with cups and candelabra of gold, surmounted by an ark of somber wood, perhaps a coffer or a tabernacle, and there was a broad fireplace ready to be lighted, with logs and pieces of a substance similar to coal, but covered by some oily matter, which probably was to feed the flame, all neatly laid out on a bed of fresh boughs, and covered with sprigs of aromatic berries.
"It's the best room at my disposal," Ardzrouni said, "and for me it is an honor to offer it to you. I do not advise you to open that window. It's an eastern exposure and tomorrow morning the sun might bother you. These colored panes—a wonder of Venetian art—will delicately filter the light."
"No one can enter through that window?" the Poet asked.
Ardzrouni laboriously opened the window, which was, in fact, shut with various bolts. "You see?" he said. "It's very high. And beyond the court are the ramparts, where the emperor's men are already on guard." In fact, the ramparts of the outer walls could be seen, the gallery on which, at intervals, the guards passed, and, just an arrow's shot from the window, two great circles or plates of shiny metal, deeply concave, set on a support between the battlements. Frederick asked what this was.
"They are mirrors of Archimedes," Ardzrouni said, "with which that sage of ancient times destroyed the Roman vessels that were besieging Syracuse. Each mirror captures and refracts the rays of light that fall parallel to its surface, and for that matter it reflects objects. But if the mirror is not flat and is curved in the proper way, as geometry, that supreme science, teaches us, the rays are not reflected parallel, but are all concentrated in a specific point in front of the mirror, according to its curve. Now, if you so orient the mirror that it captures the sun's rays at its moment of maximum radiance and bring them to strike, all together, a single distant point, such a concentration of solar rays on that precise point creates combustion, and you can set fire to a tree, the planking of a ship, a war machine, or the dry brush around your enemies. There are two mirrors because one is curved so that it strikes at a distance, the other sets fire at a closer range. So with these two very simple machines I can defend this castle of mine better than if I had a thousand bowmen."
Frederick said that Ardzrouni should teach him that secret, because then the walls of Jerusalem would fall better than those of Jericho, not through the sound of trumpets but through the rays of the sun. Ardzrouni said he was there to serve the emperor. Then he closed the window and said: "Air doesn't enter here, but through other fissures. Despite the season, since the walls are thick, you might feel cold tonight. Rather than light the fire, which smokes annoyingly, I advise you to cover yourself with these furs you see on the bed. I apologize for my vulgarity, but the Lord created us with a body: behind this little door there is a cubbyhole, with a less than royal seat, but anything your body wants to expel will fall into a cistern undergound, without infecting this space. This room can be entered only by the door we have just passed through; beyond that, once you have fastened it from inside with the latch, your courtiers will be sleeping on those benches, perhaps not comfortably, but they will guarantee your serenity."
They noticed on the breast of the fireplace a circular relief. It was a Medusa head, the hair twisted like snakes, eyes closed, and an open fleshy mouth, which displayed a dark cavity whose bottom could not be seen ("like the one I saw with you in the cistern, Master Niketas"). Frederick became curious and asked what it was.
Ardzrouni said that it was a Dionysius ear: "It is one of my magic devices. In Constantinople there are still old stones of t
his sort; it was enough simply to carve the mouth better. There is a room, below, where as a rule my little garrison stays, but as long as you, Emperor, are here it will be left empty. Everything that is said down there comes forth from this mouth, as if the speaker were just behind the sculpture. So if I choose, I can hear what my men are talking about."
"If only I could know what my cousins are talking about," Frederick said. "Ardzrouni, you are invaluable. We will talk further also of this. Now let us make our plans for tomorrow. In the morning I want to bathe in the river."
"You can reach it easily, by horse or on foot," Ardzrouni said, "and without even passing through the courtyard where you entered. In fact, beyond the door of the salle d'armes there is a little stairway that leads to a second court. From there you can find the main path again."
"Baudolino," Frederick said, "have some horses ready in that court for tomorrow morning."
"Dear Father," Baudolino said, "I know very well how much you like to face the most turbulent waters. But now you are tired from your journey and from all the trials you have undergone. You are unfamiliar with the waters of this river, which seems to me full of whirlpools. Why do you want to risk this?"
"Because I am not so old as you think, my son, and because, if it weren't late, I would go to the river at once; I feel filthy with dust. An emperor must not stink, unless it be with the oil of holy unctions. Arrange for the horses."
"As Ecclesiastes tells us," Rabbi Solomon said timidly, "thou shalt not swim against the river's current."
"And who says I will swim against it?" Frederick laughed. "I'll follow it."
"It is not good to wash oneself too often," Ardzrouni said, "unless under the guidance of an expert physician, but here you are master. Now it is still early; for me it would be an undeserved honor to show you around my castle."
He led them back down the grand staircase. On the lower floor they crossed a hall reserved for the evening banquet, already alight with many candelabra. Then they passed through a saloon full of stools, on some of which was carved a great overturned snail, a spiral structure that closed into a funnel, with a central hole. "This is the guards' room I told you about," he said, and those who speak with their mouths to this aperture can be heard in your chamber."
"I would like to hear how it works," Frederick said. Baudolino, in jest, said that during the night he would come here to greet him as he was sleeping. Frederick laughed and said no, because that night he wanted to rest peacefully. "Unless," he added, "you have to warn me that the sultan of Iconium is entering through the fireplace flue."
Ardzrouni led them along a corridor, and they entered a hall with vast vaults, which glowed and was smoky with swirls of steam. There were some cauldrons in which a molten matter was boiling, retorts and alembics, and other curious receptacles. Frederick asked if Ardzrouni produced gold. Ardzrouni smiled, saying that such were the tall tales of alchemists. But he knew how to gild metals and produce elixirs that, if they did not grant long life, at least extended the very brief life that is our lot. Frederick said he didn't want to taste them: "God has set the length of our life, and we must resign ourselves to his will. Perhaps I'll die tomorrow, perhaps I'll live to be a hundred. It's all in the hands of the Lord." Rabbi Solomon observed that his words were very wise, and the two conversed a while on the matter of divine decrees, and it was the first time that Baudolino heard Frederick speak of these things.
While the two were talking, out of the corner of his eye Baudolino saw Zosimos, stepping through a little door into an adjoining room, with Ardzrouni, looking concerned, immediately after him. Fearing that Zosimos knew some passage that would allow him to escape, Baudolino followed the two and found himself in a little room where there was only a kneading trough, and, on top of it, seven gilded heads. All of them portrayed the same bearded countenance, and were set on pedestals. They were obviously reliquaries, because it was clear that the heads could be opened like containers, but the edges of the lids, on which the face was drawn, were fixed to the rear part by a seal of dark wax.
"What are you looking for?" Ardzrouni was asking Zosimos, not noticing Baudolino.
Zosimos replied: "I have heard that you make relics, and for them you use your diabolical skill in gilding metals. They're heads of the Baptist, aren't they? I have seen others, and now I know for sure where they come from."
Baudolino delicately cleared his throat. Ardzrouni wheeled around and put his hands to his mouth, his eyes rolling with fear. "I beseech you, Baudolino, say nothing to the emperor, or he'll have me hanged," he said in a low voice. "Well, yes, these are reliquaries with the true head of Saint John the Baptist. Each of them contains a skull, treated with fumigations so that it shrinks and seems very ancient. I live in this land without any resources of nature, without fields to sow, and without livestock, and my wealth is limited. I fabricate relics, true, and they are much in demand both in Asia and in Europe. I have only to sell one of these heads at a great distance from the other: for instance, one in Antioch and the other in Italy, and nobody realizes that there are two of them." He smiled with oily humility, as if asking indulgence for a sin that was, after all, venial.
"I never took you for a virtuous man, Ardzrouni," Baudolino said, laughing. "Keep your heads, but let's leave here at once; else we'll arouse the suspicions of the others, including the emperor." As they went out, Frederick was concluding his exchange of religious reflections with Solomon.
The emperor asked what other prodigious things their host had to show them, and Ardzrouni, anxious to get them out of that room, led them back into the corridor. From there they came to a closed double door, beside which was an altar of the kind pagans used for their sacrifices, altars of which Baudolino had seen many remains in Constantinople. On this one there were faggots and twigs. Ardzrouni poured over them a thick, dark liquid, took one of the torches illuminating the corridor, and set the pile afire. Immediately the altar flared up, and in the space of a few minutes they began to hear a faint subterranean churning, a slow creak, while Ardzrouni, with arms upraised, uttered formulas in a barbaric language, but looking now and then at his guests, as if to let them know he was imitating a hierophant or necromancer. Finally, to the amazement of all, the two leaves of the door opened without anyone's having touched them.
"Wonders of the hydraulic art"—Ardzrouni smiled with pride—"which I cultivate, following the learned mechanics of Alexandria, of many centuries ago. It's quite simple: beneath the altar there is a metal vessel that contains water, which is heated by the fire on the altar. The water is transformed into steam and, through a syphon, which is merely a bent pipe that serves to decant the water from one place to another, this steam goes to fill a bucket where, as the steam cools, it is transformed back into water; the weight of the water makes the bucket fall lower; descending, the bucket, through a little pulley from which it hangs, moves two wooden cylinders, which act directly on the hinges of the door. And the door opens. Simple, isn't it?"
"Simple?" Frederick said. "Amazing! But did the Greeks really know such wonders?"
"These and others, and they were known also to the Egyptian priests, who used this device to command, by speaking, the opening of the doors of a temple, while the faithul cried miracle," Ardzrouni said. Then he invited the emperor to cross the threshold. They entered a room in whose center rose another extraordinary instrument. It was a leather sphere fixed to a circular surface by what seemed to be handles bent at right angles, and the surface held a kind of metallic basin beneath which there was another pile of wood. From the sphere, above and below, ran two little pipes, which ended with two taps facing in opposite directions. On closer observation, you could see that the two handles holding the sphere to the round level were also pipes, which below were fixed to the basin, and above penetrated the interior of the sphere.
"The basin is filled with water. Now we'll heat this water," Ardzrouni said, and again he started a great fire. They had to wait a few minutes before the water came to a boil, then
a hissing was heard, faint at first, then louder, and the sphere began to revolve around its supports, while from the taps came puffs of steam. The sphere turned for a little while, then its impetus seemed to weaken, and Ardzrouni hastened to seal the little faucets with a kind of soft clay. He said: "Here again the principle is simple. The water boiling in the basin is transformed into steam. The steam rises in the sphere, but, emerging violently from opposite directions, it imposes on it a rotary motion."
"And what miracle does it pretend to be?" Baudolino asked.
"It doesn't pretend anything, but it demonstrates a great truth: namely, it allows us to see the existence of the vacuum."
Just imagine Boron then. Hearing the vacuum mentioned, he became suspicious at once and asked how this hydraulic toy proved that the vacuum exists. "It's simple," Ardzrouni said. "The water in the basin becomes steam and fills the sphere, the steam escapes the sphere making it rotate; when the sphere looks as if it will stop, it's a sign that it has no more steam, so you close the taps. And then what remains in the basin and in the sphere? Nothing: that is to say, the vacuum."
"I'd really like to see it," Boron said.
"To see it, you'd have to open the sphere, and then air would immediately enter. However, there is a place where you can stand and sense the presence of the vacuum. But you are aware of it only briefly, because, for lack of air, you will die of suffocation."
"And where is this place?"
"It's a room above us. Now I'll show you how I can create a vacuum in that room." He held up the torch and showed us another machine that till then had remained in the shadows. It was far more complex than the two previous ones, because it had, so to speak, its viscera exposed. There was an enormous alabaster cylinder, which showed in its interior the dark shadow of another cylindrical body that occupied half of it, while half protruded, its upper part bolted to a kind of enormous handle that could be operated by a man's two hands, as if it were a lever. Ardzrouni operated that lever, and the inner cylinder was seen to move first up, then down, until it completely occupied the exterior cylinder. To the upper part of the alabaster cylinder a great tube was attached, made of pieces of animal bladders, carefully sewn together. This tube was finally swallowed by the ceiling. On the lower part, at the base of the cylinder, a hole opened.