Watson had come to see me off at the station, that chilly morning in November when a quiet yet momentous shift took place in that strange thing that existed between us.
He followed me through the crowd, clutching his platform ticket, until we found a quiet corner in which to wait. He appeared to be gazing vaguely at the streams of humanity flooding in from the departure hall, but I, who knew him so well, could read the subtle unhappy lines in which his face was set. I myself was facing the coming hours with no greater equanimity. We had endured many separations before, of course, but never with such a distinct possibility of it being our last. On the Continent I would face an enemy whose personal grudge against me made him far more dangerous than a criminal with twice his skill.
Meanwhile we stood waiting on the platform, a respectable inch of air between us, remembering the fervent kisses and desperate clutching hands of a few hours before. We had woken early, despite the lateness of the hour when we finally, reluctantly surrendered to sleep.
Watson gave a sudden exclamation of annoyance. I pushed away the thought of how much I would miss his sighs and exclamations, his unconscious tuts and clickings of the tongue. When would I next hear him groan my name in abandon, or snap it because I had left formaldehyde on the dinner table once more? I believed I would miss the latter just as much as the former.
"Bother," he said. "It looks like your train is delayed." I had already seen the commotion among the railway employees on the platform, and now we watched as a guard came running up with chalk and a footstool, to mark the delay on the departures board.
I raised an eyebrow. "So keen to be rid of me?" I knew perfectly well he was not.
"I would rather have spent the extra time at home in private," he said, unable to keep a sour note from his voice.
I followed his gaze and saw a young lady (a former typist and a florist at her church) with her husband (marine clerk, keen billiards player), a few feet away from us. The gentleman's suitcase lay abandoned on the ground beside him as they took advantage of the precious extra minutes, entwined in each other's arms as closely as decorum would allow.
I touched his sleeve, a poor substitute and a poor consolation.
"I will write," I said.
We had spent the past few days ignoring my imminent departure, pretending it would be a separation like any other, and that there was not a very good chance I would not return to England alive. I had not told Watson all the details of my plans for Brussels, of course, but if he were not so intelligent I would not have hung onto him with such determination for the past two years. I knew he was perfectly well aware of the magnitude of the danger.
Opposite us, the Brighton Express was preparing to depart. The last few stragglers came hurrying down the platform. The railway guard's whistle pierced my head. The high arched ceiling above us filled with smoke and the train began to move.
Beside me, I could feel Watson watching me instead of our surroundings.
"I hope you won't allow your brain to stagnate while I'm gone," I said without turning my head. "Just when I was finally beginning to make some paltry progress."
I felt a hand clasp my elbow briefly, and I knew he understood that I had meant I'll miss you.
From where I stood I could see the first train in from Dover that morning, the charladies already busy cleaning out its Pullman cars. Two of them were slacking off, rather more of their energy going into their conversation than their scrubbing. Porters were tossing parcels out of the train's goods van in a way that would have appalled the senders. At the far end of the platform, a ticket collector had disappeared behind a pillar for a hurried cigarette. These were little sins, little transgressions. Nothing that struck at the very fabric of society - something I had always taken a certain perverse pleasure in doing, and particularly so now that I had Watson as my willing accomplice.
It amused me to think of the truth behind the hero of Baker Street, that valiant upholder of the law. My life had never run on lines of standard gauge, but some vices turned out to be more socially palatable than others. Fortunately, my talent for obfuscation and misdirection had grown apace with my celebrity, and I had acquired a biographer who was equally skilled, as well as having a personal stake in the matter.
I wondered what would happen if I were to grab Watson, there on the platform, and kiss him senseless. A certain reckless part of me would relish the practical demonstration of man's hypocrisy. Poor Watson would have had a heart attack, though. I dismissed the fantasy, and let my gaze roam on over the crowd, observing and cataloguing.
Nearby, an elderly gentleman (retired watch-mender, visiting family) was clutching a Bradshaw, its yellow wrapper unmistakable. I had memorised a good portion of that work's minutiae, and I could never help but admire the painstaking effort that went into compiling the timetables, bringing order to the chaos of hordes of competing railway companies. Watson's introduction into my own orderly life had been an almost insupportable disruption at first, an unclassifiable entry to my rational philosophy. When first we met, I had never dreamt we should eventually grow so tolerant of one another - to put it mildly - that a separation would provoke such a keen, almost physical pain.
My eye was caught by a newly-wedded couple coming down the platform towards us, the man overly solicitous about finding his young lady a seat, the girl's gaze returning every few moments to her ring. Watson turned away. I knew the stab of jealousy he felt without even looking. I had read it in his eyes often enough.
On impulse, I bent my head to speak into his ear. "I would share that honourable estate with you without a moment's hesitation, were it possible."
He turned sharply towards me. The platform was overflowing with the other passengers waiting for the delayed train. Barely five feet separated us from our nearest neighbours, but Watson had eyes only for me.
"If you would have me, of course," I added, though I did not doubt his response. "It is not something to be undertaken lightly, you know, but rather reverently, discreetly, advisedly, soberly, and in the fear of God." I could not suppress a wry note in my voice, but I was quite sure Watson knew how much in earnest I was.
His eyes widened as he recognised the words. He made a small movement as though to close the gap between us, but restrained himself. "Believe me, I have never been more serious in my life when I say I would. Of course I would."
The scope of my senses had shrunk to encompass only the little patch of platform in which Watson and I stood, separated by a mere two feet of air. He was grinning into his moustache, his eyes crinkling up into lines of joy. I could feel an answering smile spreading across my own face.
"Then let us consider the matter settled," I said quietly.
It was such a simple thing, on the face of it, and yet overwhelming. We had arrived here by a long and circuitous path, but I could not imagine having taken any other. Now, I could only stare at Watson, the look of dazed euphoria in his eyes reflecting the state of my own heart.
I was startled by a sudden surge of movement towards the train. For a moment I was disoriented, amazed that I had been so completely detached from my surroundings as to miss the announcement of its departure. The thought of our impending separation came flooding back as I turned to pick up my suitcase.
"Let me," said Watson, reaching for the handle at the same moment and taking the opportunity to discreetly squeeze my hand.
He led the way across the platform to the waiting train. My gaze was fixed on his broad square back, wrapped up in thick winter tweed, and I wished desperately that I were following him back to Baker Street. I ached to touch him, away from censorious eyes.
"Does this mean you cannot fail to return safe and sound from the Continent?" he said with a small smile, as we reached the carriage door. "Since those whom God has joined no man can put asunder, I mean - not even Belgian psychopaths."
"I had already intended to do so," I said sternly, but I was smiling too. It was not rational, but suddenly the world seemed a different place.
We had just time for a brief handshake before the guard's whistle sounded along the platform. I sprang into the carriage and Watson handed me up my suitcase.
"Don't do anything reckless," he called as the train began to move.
I am sorry to say I did several things he would have considered reckless, but I came safely back to England all the same. In the years that followed we faced many dangers together, darker and more terrible than that one. We endured separations that sometimes lasted years, and weathered disputes and fallings-out of our own making. Down all the decades, however, I never lost that sense of wonder that Watson was mine, and I his.