'So, do we take leave of one another until morning, Signor Cristofano?'
'No, I have fixed the appointment with Devize immediately before luncheon. That is the ideal time: the sun is high and the energy of the musical vibrations can spread to the maximum. Good night, my boy.'
Night the Eighth
Between the 18th and 19th September, 1683
'Closed! It is closed, damn it!'
That was to be expected, I thought, while Atto Melani pushed uselessly against the trapdoor that led to Tiracorda's stables. Already, when we were marching through the galleries, escorted by the subdued muttering of Ugonio and Ciacconio, this latest nocturnal expedition to the house of Tiracorda seemed to me destined to fail. Dulcibeni had discovered that we were keeping an eye on him. Perhaps he did not imagine that we had already spied upon him in Tiracorda's study, but he would never have wished to run the risk of being observed while conducting strange trafficking with (or against) his old friend. And indeed, after entering his fellow-countryman's home, he had made sure that the trapdoor was locked.
'Excuse me, Signor Abbot,' said I while Atto wiped his hands nervously, 'but perhaps it is better like this. If tonight Dulcibeni notices nothing strange while he is playing at riddles with Tiracorda, perhaps tomorrow we shall find our way free.'
'Not a bit of it,' replied Atto crossly, 'he knows now that he is under observation. If he intends to accomplish something strange, he will do it as early as possible: even tonight; or tomorrow, at the latest.'
'And so?'
'And so, we must find a way of entering Tiracorda's house, even if I really do not know how. We would need…'
'Gfrrrlubh,' interrupted Ciacconio, stepping forward.
Ugonio looked at him frowning, as though in reproof.
'At last, a volunteer,' commented Abbot Melani, satisfied.
A few minutes later, we were divided into two unequal groups. Atto, Ugonio and I marched along gallery C, in the direction of the underground river. Ciacconio, on the other hand, had climbed to the surface up the well which led from the same conduit to the Piazza della Rotonda, near the Pantheon. He had not been willing to explain to us how he intended to effect his entry into the house of Tiracorda. We had patiently explained to him, down to the smallest details, how the physician's house was laid out, but only at the very end did the corpisantaro candidly declare that the information would be absolutely of no use to him. We had even provided him with a sketch of the house, including the disposition of the windows; but, hardly had we separated than we heard resounding in the gallery a frenetic, goatlike sound of mastication. The life of our sketch, on which Ciacconio was horribly banqueting, had been all too brief.
'Do you think he will succeed?' I asked Abbot Melani.
'I have not the least idea. We explained to them ad nauseam every single corner of the house, but it is as though he already knew what to do. I cannot bear them, those two.'
In the meantime, we were rapidly advancing towards the small underground river where, two nights previously, we had seen Dulcibeni mysteriously disappear. We passed close to the old and nauseating carcasses of the rats, and very soon we heard the sound of the subterranean watercourse. This time we were better equipped: at Atto's request, the corpisantari had brought with them a long and robust rope, a few iron nails, a hammer and a few long staves. These would be useful for the perilous and somewhat unwise operation which Atto intended at all costs to perform: to ford the river.
We stood for who knows how long, pensively observing the watercourse, which seemed more black, fetid and threatening than ever. I shivered, imagining a ruinous fall into that disgusting and hostile current. Even Ugonio seemed worried. I sought to bolster up my courage by addressing a silent prayer to the Lord.
Suddenly, however, I saw Atto move away from me and direct his gaze towards a point where the right-hand wall of the gallery formed an angle with the channel through which the river ran. For a few moments, Atto remained immobile opposite the corner between the two conduits. Then he stretched out a hand along the wall of the fluvial gallery.
'What are you doing?' I called out in alarm, seeing him lean dangerously towards the river.
'Keep quiet,' he whispered, groping ever more eagerly at the wall, as though he were seeking something.
I was about to run to his assistance, fearing that he might lose his balance. It was precisely then that I saw him at last retreat from this dangerous exposure, grasping something in his left hand. It was a little painter of the kind which fishermen use to moor their boats on the Tiber. Atto began to pull on the cord, gradually coiling it. When at last there seemed to be resistance at the far end, Atto invited Ugonio and myself to look at the little river. Just in front of us, faintly illuminated by the light of the lantern, there floated a flat-bottomed boat.
'I think that by now even you will have understood,' said Abbot Melani soon afterwards, as we navigated in silence, driven by the current.
'No, I really do not,' I admitted. 'How did you manage to discover the boat?'
'It is simple. Dulcibeni had two possibilities: to cross the river or to go down it by boat. In order to take the river, however, he needed to have a boat moored at the point where the two galleries intersect. When we arrived, there was no trace of any boat; but, if there had been one, it would surely have been subject to the pull of the current.'
'So, if it was secured by a rope,' I guessed, 'it would be pulled downstream by the current into the gallery to our right, where it flows down towards the Tiber.'
'Exactly. The mooring had therefore to be secured to a point situated to the right in relation to gallery C, in other words, in the direction of the current. Had it been otherwise, we should have seen the hawser stretched from left to right, towards the boat. That was why I looked for the cord on the right. It was secured to an iron hook, which had been placed there who knows how long ago.'
While I meditated upon this new proof of Abbot Melani's sagacity, Ugonio increased our pace by pulling gently on the two oars with which the boat was equipped. The bare landscape illuminated by our lantern was dull and monotonous. On the vaulted stone roof of the gallery, we heard the echo of the waves lapping against our fragile bark.
'But you were not sure that Dulcibeni had used a boat,' I suddenly objected. 'You said: 'Now, if there had been one…''
'Sometimes, in order to know the truth, it is necessary to presuppose it.'
'What do you mean?'
'It frequently happens like this in affairs of state: in the presence of inexplicable or illogical facts, one must figure out what must have been the indispensable condition which determined them, however incredible it may be.'
'I do not understand.'
'The most absurd truths, my boy, which are also the blackest ones, never leave any traces. Remember that.'
'Does that mean that they will never be discovered?'
'Not necessarily. There are two possibilities: the first is that there may be someone who knows or who has understood, but who has no proof.'
'And what then?' I asked, understanding very little of the abbot's words.
'He then constructs the proof which he does not have, so that the truth comes to the surface,' replied Atto candidly.
'Do you mean that one can encounter false proofs of real facts?' I asked, open-mouthed.
'Bravo. But do not be surprised. You must not fall into the common error of believing, once it has been discovered that a document or a proof was counterfeited, that its content, too, is false. The contrary is likely to be true. Remember that when you become a gazetteer: often the most horrendous and unacceptable truths are
