A reader who has followed the catalogue this far has formed, without being handed it, a picture of how the worlds lie. It is worth setting that picture down plainly, because the shape of the charted multiverse is not the shape most travellers carry, and the difference matters to anyone who means to cross.
The largest correction first. The worlds do not lie at distances from one another. A veil sets a crosser at the far side in the space of a single step, and the step is not shorter for joining near worlds or longer for joining far ones, because near and far are not terms the crossing answers to. Two worlds a veil joins are, for the crossing, adjacent; two worlds no veil joins are not far apart, but simply not joined. The survey charts the multiverse not as a space with things placed in it but as a pattern of joinings: which worlds open onto which, and how heavily travelled. A map of the worlds is a map of doors. It holds what connects to what, not how far anything is from anything else.
The texture of the worlds follows. Crossing-worlds, opened onto by many veils, are the dense places of the map, dense not by location, which they lack, but by joining, and they grow their markets and lodgings on no foundation but the accident of being well-joined. Frontier worlds lie at the thin edge, reached by a single veil and opening onto nothing further, called frontier not for being distant, distance being nothing here, but because the pattern thins to one thread before it reaches them. And some worlds are reached by a veil that does not return the way it came, the arrival sound and the way home, if there is one, running by another door or none the survey has found; the catalogue holds such worlds set down as reached, not yet set down as left.
A thing with no distances is charted one crossing at a time. The survey holds no vantage above the pattern, there being no above; it learns the pattern only by crossing and returning, the map growing door by door. What is charted is what has been crossed and returned from. Veils uncrossed, or crossed and not returned from, are marked and not filled in, and the map is everywhere edged with these. How much of the multiverse the catalogue has charted is a number the survey does not give, not from discretion but from honesty, there being no way to know the size of a whole one can only meet a piece at a time.
A last thing, often misunderstood. None of this has retired ordinary travel. Within a world, and within its system, distance is what it has always been, crossed on foot, by sea, by air, and by the ships that cross between the bodies of their own systems, as those peoples did long before any of them found a veil. A veil does not move a traveller through the space of a system; it joins two places that have no space between them. The veils sit beside ordinary travel, not over it: they reach the between, where there is nothing for a ship to cross, and leave the rest of distance to the ships and the roads and the sea.
There the matter rests.
~ The Lectors
