The nearest of these was at the perimeter, around the Boulevard Périphérique - the city's ring road. The book as the man had presented it was, although described as a novel, based on close factual description of a small suburban area and its inhabitants, on the one hand, and the life and times of a true historical figure who had given his name to a street at its centre - Avenue Ney, after the marshal of the Napoleonic era.
Densely descriptive, the text kept returning to a few essential features which had stuck in my memory thanks to the account at St Pancras. The cheap and characterless hotels, mostly there to serve the motorway, in which the narrator lived, the cafés, canal bridges, high-rise blocks, railway lines, and, at the heart of the story, beneath the motorway itself with its almost Ballardian vocabulary of approach roads and sidings, the pillars supporting its flyover, in which, the man insisted, the main characters lived.
Now is perhaps that later. Since Jean Rolin's La Clôture, which answers to every detail of the St Pancras account, was published in 2002, it is quite impossible that I should have read it when I knew the St Pancras man, described it to him, or written the annotations on the map he claimed had been mine.
However, if this might suggest ruling out his entire story, other things still suggest otherwise. My experiences with the Aragon text, for instance, were similar, but that text I certainly could have read. And then, given the parallels in the Aragon text with our experiences here in London, if I was to apply its principles, as I clearly should, it may be that my sense of recognition, outweighing any narrow conception of factual possibility, should dictate its figuring in a blog such as this, bent on uncovering, not the superficial, but the underlying facts.
These, then, were the two mysteries presenting themselves to me at the end of the first day in Paris. Whether or not the events of the second day resolved the puzzle, I cannot yet say. However, the very least that I had was good reason to continue the search, and you can be sure I took as close a record of my activities as usual.