The belfry had already been enclosed by it’s designers, with only a few slits to the outside world that were made to blend in to the stone when looked at from outside. We’d brought up some wooden boards and painted them black before boarding those slits over from the inside and draping plenty of blackout curtains over them, just to keep the illusion up. Indeed, the only real light source inside the otherwise completely blacked out enclosure was the smattering of oil lamps hung all around on the walls, and on several coat stands placed across the floor. Most were off, but a few were kept lit for my sake. That wasn’t counting the unlit candles and torches spread around either, but those were there more for backup lighting: the lamps simply lasted far longer.