“You’re forgetting the central well. Many of the windows we have seen overlook the octagon, the well. If it were day, the difference in light would tell us which are external windows and which internal, and perhaps would even reveal to us a room’s position with respect to the sun. But after dusk no difference is perceptible. Let’s go back.”

We returned to the room with the mirror and headed for the third doorway, which we thought we had not gone through previously. We saw before us a sequence of three or four rooms, and toward the last we noticed a glow.

“Someone’s there!” I exclaimed in a stifled voice.

“If so, he has already seen our light,” William said, nevertheless shielding the flame with his hand. We hesitated a moment or two. The glow continued to flicker slightly, but without growing stronger or weaker.

“Perhaps it is only a lamp,” William said, “set here to convince the monks that the library is inhabited by the souls of the dead. But we must find out. You stay here, and keep covering the light. I’ll go ahead cautiously.”

Still ashamed at the sorry figure I had cut before the mirror, I wanted to redeem myself in William’s eyes. “No, I’ll go,” I said. “You stay here. I’ll proceed cautiously. I am smaller and lighter. As soon as I’ve made sure there is no risk, I’ll call you.”

And so I did. I proceeded through three rooms, sticking close to the walls, light as a cat (or as a novice descending into the kitchen to steal cheese from the larder: an enterprise in which I excelled at Melk). I came to the threshold of the room from which the glow, quite faint, was coming. I slipped along the wall to a column that served as the right jamb, and I peered into the room. No one was there. A kind of lamp was set on the table, lighted, and it was smoking, flickering. It was not a lamp like ours: it seemed, rather, an uncovered thurible. It had no flame, but a light ash smoldered, burning something. I plucked up my courage and entered. On the table beside the thurible, a brightly colored book was lying open. I approached and saw four strips of different colors on the page: yellow, cinnabar, turquoise, and burnt sienna. A beast was set there, horrible to see, a great dragon with ten heads, dragging after him the stars of the sky and with his tail making them fall to earth. And suddenly I saw the dragon multiply, and the scales of his hide become a kind of forest of glittering shards that came off the page and took to circling around my head. I flung my head back and I saw the ceiling of the room bend and press down toward me, then I heard something like the hiss of a thousand serpents, but not frightening, almost seductive, and a woman appeared, bathed in light, and put her face to mine, breathing on me. I thrust her away with outstretched hands, and my hands seemed to touch the books in the case opposite, or to grow out of all proportion. I no longer realized where I was, where the earth was, and where the sky. In the center of the room I saw Berengar staring at me with a hateful smile, oozing lust. I covered my face with my hands and my hands seemed the claws of a toad, slimy and webbed. I cried out, I believe; there was an acid taste in my mouth; I plunged into infinite darkness, which seemed to yawn wider and wider beneath me; and then I knew nothing further.

I woke again after a time I thought was centuries, hearing some blows pounding in my head. I was stretched out on the floor and William was slapping me on the cheeks. I was no longer in that room, and before my eyes was a scroll that said “Requiescant a laboribus suis,” “May they rest from their labors.”

“Come, come, Adso,” William was whispering to me. “There’s nothing….”

“Everything…” I said, still delirious. “Over there, the beast…”

“No beast. I found you raving underneath a table with a beautiful Mozarabic apocalypse on it, opened to the page of the mulier amicta sole confronting the dragon. But I realized from the odor that you had inhaled something dangerous and I carried you away immediately. My head also aches.”

“But what did I see?”

“You saw nothing. The fact is that some substances capable of inducing visions were burning there. I recognized the smell: it is an Arab stuff, perhaps the same that the Old Man of the Mountain gave his assassins to breathe before sending them off on their missions. And so we have explained the mystery of the visions. Someone puts magic herbs there during the night to convince importunate visitors that the library is guarded by diabolical presences. What did you experience, by the way?”

In confusion, as best I could recall, I told him of my vision, and William laughed: “For half of it you were developing what you had glimpsed in the book, and for the other half you let your desires and your fears speak out. This is the operation certain herbs set in action. Tomorrow we must talk about it with Severinus; I believe he knows more than he wants us to believe. They are herbs, only herbs, requiring none of those necromantic preparations the glazier talked to us about. Herbs, mirrors … This place of forbidden knowledge is guarded by many and most cunning devices. Knowledge is used to conceal, rather than to enlighten. I don’t like it. A perverse mind presides over the holy defense of the library. But this has been a toilsome night; we must leave here for the present. You’re distraught and you need water and fresh air. It’s useless to try to open these windows: too high, and perhaps closed for decades. How could they think Adelmo had thrown himself down from here?”

Leave, William had said. As if it were easy. We knew the library could be reached only from one tower, the eastern one. But where were we at that moment? We had completely lost our orientation. We wandered, fearing never to emerge from that place again; I, still stumbling, seized with fits of vomiting; and William, somewhat worried about me and irritated by the inadequacy of his learning; but this wandering gave us, or gave him, an idea for the following day. We would come back to the library, assuming we ever got out of it, with a charred firebrand, or some other substance capable of leaving signs on the walls.

“To find the way out of a labyrinth,” William recited, “there is only one means. At every new junction, never seen before, the path we have taken will be marked with three signs. If, because of previous signs on some of the paths of the junction, you see that the junction has already been visited, you will make only one mark on the path you have taken. If all the apertures have already been marked, then you must retrace your steps. But if one or two apertures of the junction are still without signs, you will choose any one, making two signs on it. Proceeding through an aperture that bears only one sign, you will make two more, so that now the aperture bears three. All the parts of the labyrinth must have been visited if, arriving at a junction, you never take a passage with three signs, unless none of the other passages is now without signs.”

“How do you know that? Are you an expert on labyrinths?”

“No, I am citing an ancient text I once read.”

“And by observing this rule you get out?”

“Almost never, as far as I know. But we will try it, all the same. And besides, within the next day or so I will have lenses and time to devote myself more to the books. It may be that where the succession of scrolls confuses us, the arrangement of the books will give us a rule.”

“You’ll have your lenses? How will you find them again?”

“I said I’ll have lenses. I’ll have new ones made. I believe the glazier is eager for an opportunity of this kind, to try something new. As long as he has the right tools for grinding the bits of glass. When it comes to bits of glass, he has plenty in his workshop.”

As we roamed, seeking the way, suddenly, in the center of one room, I felt an invisible hand stroke my cheek, while a groan, not human and not animal, echoed in both that room and the next, as if a ghost were wandering from one to the other. I should have been prepared for the library’s surprises, but once again I was terrified and leaped backward. William must have had an experience similar to mine, because he was touching his cheek as he held up the light and looked around.

He raised one hand, examined the flame, which now seemed brighter, then moistened a finger and held it straight in front of him.

“It’s clear,” he said then, and showed me two points, on opposite walls, at a man’s height. Two narrow slits opened there, and if you put your hand to them you could feel the cold air coming from outside. Putting your ear to them, you could hear a rustling sound, as of a wind blowing outside.

“The library must, of course, have a ventilation system,” William said. “Otherwise the atmosphere would be stifling, especially in the summer. Moreover, those slits provide the right amount of humidity, so the parchments will not dry out. But the cleverness of the founders did not stop there. Placing the slits at certain angles, they made sure that on windy nights the gusts penetrating from these openings would encounter other gusts, and swirl inside the sequence of rooms, producing the sounds we have heard. Which, along with the mirrors and the herbs, increase the fear of the foolhardy who come in here, as we have, without knowing the place well. And we ourselves for a moment thought ghosts were breathing on our faces. We’ve realized it only now because the wind has sprung up only now. So this mystery, too, is solved. But we still don’t know how to get out!”

As we spoke, we wandered aimlessly, now bewildered, not bothering to read the scrolls, which seemed all alike. We came into a new heptagonal room, we went through the nearby rooms, we found no exit. We retraced our steps and walked for almost an hour, making no effort to discover where we were. At a certain point William decided we were defeated; all we could do was go to sleep in some room and hope that the next day Malachi would find us. As we bemoaned the miserable end of our bold adventure, we suddenly found again the room from which the stairway descended. We fervently thanked heaven and went down in high spirits.

Once we were in the kitchen, we rushed to the fireplace and entered the corridor of the ossarium, and I swear that the deathly grin of those fleshless heads looked to me like the smiles of dear friends. We re-entered the church and came out through the north door, finally sitting down happily on the tombstones. The beautiful night air seemed a divine balm. The stars shone around us and I felt the visions of the library were far away.

“How beautiful the world is, and how ugly labyrinths are,” I said, relieved.

“How beautiful the world would be if there were a procedure for moving through labyrinths,” my master replied.

We walked along the left side of the church, passed the great door (I looked away, to avoid seeing the elders of the Apocalypse: “Super thronos viginti quatuor”!), and crossed the cloister to reach the pilgrims’ hospice.

At the door of the building stood the abbot, staring at us sternly. “I have been looking for you all night,” he said to William. “I did not find you in your cell, I did not find you in church….”

“We were pursuing a trail…” William said vaguely, with visible embarrassment. The abbot gave him a long look, then said in a slow and severe voice, “I looked for you immediately after compline. Berengar was not in choir.”

“What are you telling me?” William said, with a cheerful expression. In fact, it was now clear to him who had been in ambush in the scriptorium.

“He was not in choir at compline,” the abbot repeated, “and has not come back to his cell. Matins are about to ring, and we will now see if he reappears. Otherwise I fear some new calamity.”

At matins Berengar was absent.