Wall of Light

"WARNING: ACTIVE WALL OF LIGHT - MAKE SURE YOU HAVE YOUR BADGE!" - Mandatory notice by (most) walls of light

Despite their official name, the walls of light are not truly solid walls, though they are readily treated as such. A wall of light consists of two electrical pylons set on either side of an entryway, typically powered by whale oil, though other power sources have been known to see use. The devices are then attuned to specific frequencies of objects, such as the badges carried by the City Watch or other such officials. Should anything or anyone attempt to pass through without bearing the attuned object, they are immediately disintegrated. While originating in Gristol to assist in the securing of checkpoints between districts during the height of the rat plague, the walls of light have since become a popular feature of nearly every Isle in the Empire.