Tuesday arrived. Erik had spent the previous couple of days, after his second walk with Nadir in a kind of hectic joy – the lows hadn't been too low, the highs had been unexpectedly high, and there was a sense of a future beyond endless work.

They had walked for hours into the night and finally arrived back at his apartment having talked themselves hoarse, but thankfully avoiding any more difficult disclosures about his weird childhood, leaving Erik with that glorious sense of having known Nadir for years. But he had not invited Nadir up to his room feeling, despite everything, profoundly reluctant to have to confront that difficult process of revealing his horrid face. And Nadir did not force the issue! And this did not throw him into a frenzy of self-doubt but seemed instead, to Erik, to come from a place of consideration. Were there any limits to this man's wonder?

He spent Tuesday morning at the practice gathering together all of his drawings and ideas, filling a large folio case. He had no idea what M. Mazanderani would want to see, but he felt perhaps that now, of all times, he could really expound upon his inventions and his thoughts. If his mood was right, he loved to talk and talk about these things, in the way that had done on the day he'd first met Nadir.

The previous evening it had occurred to him to think of something to give to Nadir, a kind of demonstration of his appreciation of the man. The giving and receiving of things had, in the past, been fraught for him. Things had happened with his mother to do with the receiving of gifts that had been so horrific that he had almost managed to convince himself that he'd forgotten about them completely. And Guizot had given him so much in terms of material goods – books and instruments and tools – that he would be forever in his debt.

And yet it had felt as if Nadir had turned his life around with a simple brioche – his giving was simple, and because of its simplicity it had seemed to Erik that it was something that he could learn to do. So his gift to Nadir would comprise of two parts: A list of all the pieces he would promise – not maybe! – to play to him, one evening, when he had dared to invite him to his room. And a box of macarons in all the colours.

That afternoon, Erik arrived at M. Mazanderani's apartments near the Boulevard des Italiens in good time. He was inordinately pleased with himself for being on time, having become increasingly chaotic in his timekeeping in recent weeks. He was received formally by a servant who took his hat and coat, and was shown up into a well-appointed first-floor apartment. And there was Nadir! He clenched his jaw in an effort not to grin inappropriately at Nadir who seemed to be studiously ignoring his gaze. He greeted Mazanderani and they all sat around a low table that was already set with things for coffee.

Erik felt a stupid excitement rising in his chest at being again the presence of Nadir, like this, with another person who knew nothing of their - what was it? – friendship? More than that surely? He had a wild desire to laugh with the secret of it but was kept in check mainly by looking at the expression of utter seriousness on Nadir's face. There would be no subtle looks exchanged here. Nadir was a closed book.

They made brief and boring small talk over the coffee, Nadir playing the patient translator, and they moved quickly to the bigger table in the room, over which Erik was invited to spread his work. When he had emptied the folio, he took a step back and allowed Mazanderani to look at his work. Nadir was across the other side of the room, eyes cast down, unreachable. Erik forced himself to concentrate on his work on the table, waiting attentively to answer any questions the man might have.

There was a design for a new type of ratchet; an improvement on the pin-tumbler lock; ideas for achievement of flight building on the work of Cayley, a lovely design for a double helical staircase in metal and stone, inspired by the staircase at the Chateau de Chambord – he had been thrilled to run up and down that staircase when he and Guizot had come upon the place half abandoned and even more so when he was told that it might be work of da Vinci himself; a grand design for an acoustically superior concert auditorium, a funny little series of sketches for a room of mirrors that could be made to resemble a forest with the addition of a single iron tree – Erik didn't know why he'd brought those along, everything else here at least had a use; a moving staircase powered by an electric motor; and some fantastical ideas for buildings using steel to enable them to reach a great height into the sky.

Mazanderani wanted explanations for how each of these worked, the theories and the mathematics behind them. He asked Erik to draw additional sketches as he talked and pushed Nadir's understanding of technical French and Farsi to its absolute limits, meaning that much of what was explained was done so by Erik in the form of many additional quick, clear drawings, and mathematical formulae. They discussed theories of sound transmission, the way acoustic architecture might develop over the next few years, improvements that could be made to the electric motor and its uses, developments in the use of steel in construction, the application of Euler's mathematics in structural engineering and his ideas of music theory, and Helmholtz's work on human hearing and his theories on energy. Mazanderani was an excellent scholar and Erik began to half-form notions of returning to him repeatedly to teach. Teaching!

At times, Nadir stood back and paused before he translated Erik's words, as if to say, 'I think you are making all this nonsense up.' They were brought endless coffee which Erik drank until his hands shook. He had always experienced a kind of freedom in this world of ideas and theories; for him they were a perfect escapism, into the concretely abstract world of mathematics and structure, sound and music. If he could stay here, in his mind, all of the time, that would surely be no bad thing. It was his awful heart and his terrible body that were the things that he so fervently desired to be without, the things that caused him so many difficulties.

Finally, well into the evening and several hours after all the lamps had been lit, Mazanderani announced that it was time to stop. Nadir looked exhausted and told Erik rather grimly that next time he shouldn't bring so many ideas along with him. Erik could only agree, his mouth dry with all that talking, his pulse hammering from all the coffee and now plagued by a desperate need to pee. Now that the talking was over, he felt a sudden need to escape the place. Nadir had continued to be unreadable and the absence of the distraction of the work meant Erik's mind turned gleefully to wondering exactly what Nadir was playing at.

He gathered his work together as quickly as he could and as he was doing so Mazanderani took his leave, thanking him profusely, and left him alone in the room with Nadir. What he wanted to say to Nadir was where have you gone? But he wanted more than that was to show Nadir that he could be normal and behave normally, calmly and rationally, and so he said instead, trying to be normal, "you did well to keep up, do you think you managed it all?"

"Ah - I am sorry I was so cool with you Erik. I knew as soon as you arrived that you were - "

"- going to let you down? Expose you? Christ, Nadir." It was the first time he had ever noticed Nadir looking anything other than deeply at ease with himself and with his surroundings. Nadir paused and looked intensely at Erik.

"It would not do. He is very keen to make a good impression on Parisian society. It would not do to have any kind of rumour or suspicion on his part that I am anything other than a respectable widower. Or any kind of rumour or suspicion on the part of his associates about the nature of his employees"

"Widower? You never said – "

"You never asked." Nadir smiled and moved closer to Erik. "Don't look down like that. Listen. I have a plan. Leave your work here. I will say to him that you wanted to leave it so that he could look through it again at his leisure. You leave and walk back towards the river. I'll catch up with you – don't walk too fast!"

"I thought you'd – I thought you were – "

"Stop thinking." He scooped up Erik's satchel and gave it to him. "Go!"

Within a couple of minutes, Erik was out on the street, his red scarf wound around his neck, his satchel slung over his chest. What he didn't want was hours of walking. The excitement and pleasure of the afternoon were transforming into something unpleasant, and he felt nervous and jumpy; it had been hours since his last dose, and his nose and eyes were beginning to weep of their own accord. At least it was dark. He stopped in a place that he hoped wasn't someone's front door and relieved himself. And then he tried to walk slowly, hands in tight fists in his pockets, shoulders tense. How would Nadir even know where fuck he had gone?

Presently someone touched him lightly at his elbow. He flinched so hard that he almost broke into a run.

"Erik – it's me."

"Don't do that! Do not touch me! Like that!"

"Oh! Calm yourself!" He laughed, "come on, we will walk."

They walked in silence for a few minutes. Erik tried to pull himself together.

"Where would you like to go?" Nadir asked.

"I don't want to walk. I want to sit." He didn't say and drink. He could feel himself descending into a deep misanthropy that he suspected, if he let it, might grow deep enough to include Nadir. Stop it! He tucked his hand into Nadir's elbow in an effort to feel less like a nasty bastard and more like someone Nadir would want to spend time with.

"We could have something to eat?"

"Oh-no, no we couldn't."

And then quickly, as if impatient to avoid any further discussion, Nadir pulled him into the next café they passed. They found a quiet table, Erik with his back to the rest of the place, Nadir, his back to the wall. They were served quickly; coffee Nadir, anis and water for Erik.

"More coffee? Do you not sleep?"

Nadir smiled at him, "I don't drink alcohol. I am not religious but it is not something that I am accustomed to and see no reason to start now."

Erik gave a little laugh of incredulity. "I don't really know what to say. I can't imagine not. Maybe you should start?" True, the anis would do nothing at all for his growing nausea but it might serve to keep him from running off into the night. He took a large swallow of the stuff and forced himself to lower his shoulders.

What he wanted almost above everything else, almost, was to be kind to Nadir, to show him just how grateful he was, for these past few days, even for today and for his patience. "I have something for you. It is, ah, a thing I thought you might like. Two things." Oh god, what was he doing? Exactly what type of fool was he? "I know I said I might play you something, the other day. I wanted to let you know that I definitely will play you something. Next time. I have thought about the pieces and written them down. So you know. That I mean to." He pulled the list from his pocket and pushed it across the table, and then he reached into his satchel for the macrons. "And I thought you might like these. I wanted to, ah, to say – thank you." He looked down at his lap.

"Erik, this is very thoughtful of you. These past few weeks with you have indeed been very interesting. I will enjoy these now. Do you want one?"

"No - thank you.

"Nadir, I am sorry. About - the crying, and all of that - I – I don't usually behave like that - " Ah shut up, shut up. Are you going to tell him how fucking normal you are now? You're not anywhere near normal, you mad fool. And why is it always about you?

Nadir put a whole macaron in his mouth. "I was glad I could be of assistance. Food always helps, I find." He took another one. "These are so good!"

Erik smiled at Nadir and finished his drink; he knew was drinking too fast but the nausea and the nerves and the dreadful voice in his head were all growing more intense, despite his amusement at Nadir's macaron-eating technique.

"I was interested in what you were saying to my employer. He seems quite taken with you. And your ideas."

"A rival for my affections, perhaps?"

"Ha – I should think not. He is a man in very urgent need of a wife. But I can understand entirely why he is taken with you. You should know, I think it is very important to tell you, extremely important – "

"What – spit it out!"

Nadir lowered his voice.

"That you - are very attractive when you talk like that about the things you know. Watching you talk to him this afternoon, I thought – any man who can talk like that, so knowledgeably about those things," he leant forward somewhat to whisper dramatically in Erik's ear, "is the man for me!"

Oh!

Erik swallowed. "Very attractive? Are you actually blind, Nadir? Are you one of those who says, 'I love you for your mind'?"

"One of those? You have had many of those, have you?"

"Actually, surprisingly enough, I have. Well. One or two. Maybe one." He sniggered. "Let me tell you, it's quite awful. 'I love you for your mind' – oh fuck off, then!" He looked at Nadir suddenly full of dread, "don't fuck off, will you? – I don't care if you did say that – if that's what you want – "

"Erik, Erik – I say a nice thing to you and you turn it back on yourself. You should stop doing that. Immediately. I meant what I said as plainly as I said it. I thought it the first moment I saw you, in the office. And I've thought it ever since."

"Mmm. I – I - am the same."

Nadir smiled and looked at Erik's empty glass. "Would you like another?"

"Oh – yes, of course."

Nadir called the woman over, and she quickly brought him a second glass. Erik found himself looking away from her as she came close to their table, and when she brought the second glass he immediately began to drink.

Despite Nadir's efforts he could feel his mood slipping down again. He forced himself to smile, to say something normal and pleasant. "So – you said, earlier, that you are a widower?" Ah, shit. That is not a pleasant thing.

"Yes, Erik. I did say that." Nadir's face seemed to fall. "She was a beautiful woman. Her name was Rookheeya. She died in childbirth – and our son, Reza – he died three years ago. He was six."

"Oh – I am very sorry to hear that. About them." What conceivable thing could he say now? Nadir had had a son?

Nadir nodded. "It has been a sad time. I knew from early on that Reza would not be long for the world. He did not – he did not develop properly, he struggled to walk and soon after he started, he stopped. He was a lovely boy."

They sat in silence for some minutes. Nadir apparently lost in his memories, and Erik wanting more than ever to run away. His whole body felt the way teeth do when suddenly exposed to cold air, and he could feel a drip of sweat running down his back. It took all his will to remain seated. What could he possibly find to say to a widowed man and bereaved father? Finally he pulled himself up from his self-inflicted pit and said, "you must miss them, very much?"

"Yes, I do. But with each passing year, I find that I grow into the grief. It, the grief – and they, will always be a part of me. I live with their memory and somehow they still live on. In me. The love I have for them. The pain of their loss is not as sharp as it once was, and that is alright."

Erik looked at Nadir. He could not say anything. He felt immensely sad for him. And he realised with a shock that the sadness he felt was, perhaps for the first time in his pathetic little life, not for his own sake but purely for the sake of another person. And a thought occurred to Erik, luminous and bright, in the midst of all the ruination that was happening inside him; is this what it is like to be human?

"Yes."

Nadir smiled at him again. He seemed to have shaken himself from his memories. "Would you like another? It is still quite early."

Run home or stay here with this man who was, with the simple fact of his being, was bringing him to the outer edges of humanity? And who had no idea how strong anis was.

"Yes."

Erik looked over his shoulder to watch as Nadir got up from the table this time. The café was filling up now with the workers from a nearby factory finishing a late shift. He turned away from them and hunched his shoulders. His hands were clammy and he gave a great ugly sniff in a vain attempt to deal with his running nose - nasal cavity, whatever the fuck it could be called. He hoped Nadir would return quickly. The dreadful voice in his head continued to shout run run run run!

When he did return, it was also with a huge bowl of roasted chestnuts.

"You like these, don't you?"

Erik did indeed like them and felt amused that in all the history of people trying to get him to eat, Nadir was one of the only people to consider what he actually might be capable of eating. In such a situation. He took one and poured water onto the anis.

"Yes, Rookheeya and I were married young, both sixteen. We were very happy, Erik – but it took a long time for her to conceive. She was twenty when she finally came to be with child. She was twenty-one when Reza was born."

"The same age as – "

"As you, yes. There's an irony." He gave a short laugh. "You and she are quite different, never fear! And I was left with our baby son."

"What was that like?" Erik, who had no knowledge or experiences of babies whatsoever felt quietly appalled at the prospect of being left in the sole care of one. "Did you know what to do? With the – the baby?"

"I hired a nurse of course, and then I went to work and did my best to avoid the tragedy that was unfolding in my house. There was nothing to be done for him. His death was a slow and terrible thing to watch." Nadir sighed deeply and passed his hand over his face. "Ah, God. My lovely boy.

"He died eventually, from a lung condition. But it was not a merciful death. It was terrible to watch. But it was swift. In the end. I lost my faith in God."

Erik could think of nothing to say to Nadir that wasn't trite or stupid, but he was very close to tears – for Nadir, for Reza, and for himself and just how terribly ill at ease he felt. Eventually he said, "I – it is – very sad. For you Nadir. That your son and your wife died. I find it hard to imagine. But listening to you talk – it is very sad." He clenched his jaw.

"Yes, it was a tragedy, but it is something I live with. There is a peace about it now." He gave a little smile. "And this is not what I expected to be talking about with you this evening!"

"It makes a change from talking about me all the time."

They sat in silence for several minutes, somehow quite separate from the noise of those around them. Nadir finished his coffee.

"Have you finished? It is noisy here. Shall we leave? Have another nut."

Erik drained the last of the anis. "Yes. I have. Finished."

They left payment on the table, put on their coats and Erik slung his satchel over his chest. The cold air when they stepped out onto the street had its usual stirring effect on Erik's head and he was glad to take hold of Nadir's arm as they set off.

"Where shall we go now?" Nadir sounded cheerful and full of energy, evidently imagining another evening of walking and talking.

"I think - I think I would like to go home now, Nadir. I – er – I feel quite unwell." And drunk, you fool.

"Ah – would you like me to walk you back? We could get a cab?"

"I will get a cab." He couldn't bear the idea of Nadir coming back with him, as much as he longed to remain in his company. He squeezed his eyes shut with the misery of it, the misery of what he needed to do that could only be done in solitude. "I don't think I will be good company – if I ever was – this evening." He yawned.

"Ah come now, you are tired. Let us walk to the main road and we will find you one there."

They did so and soon Erik was slumped, eyes closed, in the back of a cab on his way home.

When he arrived back at the building of his apartment, he was tempted to run up the steps outside the front, and take the internal staircase two, three steps at a time. He chose, however, to have one last stab at trying to appear normal, and because of this, because of the great effort he put into walking not running, it gave Monsieur Hervé the opportunity to hand him a note. Erik, snatched it from him, muttered thank you under his breath and shoved the note down into his coat pocket. And there it would remain, unread, until the following morning.

Erik had other, far more pressing, things on his mind.

Notes:

I lost a morning reading about 19th century developments in physics and engineering trying to work out what Erik might have been thinking about in the early 1850s. I understood precisely none of it, and most of it didn't end up in the story. Physics is Erik's bag, it is resolutely not mine. 19th century physicists were amazing in what they were discovering and in the breadth of their study, which is why I think it is entirely possible that Erik would have been knowledgeable in a wide range of subjects. Scientists didn't seem to specialise in the way they do now.

Much of the stuff I think he would have been REALLY interested in happened later in the 19th century (all that to do with the understanding of sound and its recording, and acoustics) and I hope that if he'd been able to stay on the straight and narrow he'd have been able to participate actively in some of those developments.

(It is a bit weird to hope things for a fictional character?)