This is the first of the one hundred plates that make up Jerusalem. It shows Los, the personification of the poetic imagination, passing through a gothic arch. Los is dressed like a London night watchman, but his sandals strike an anachronistic note, marking him out as a prophetic figure. On closer inspection the lantern in his right hand turns out to be a miniature sun, as described in Blake’s lines ‘Los took his globe of fire to search the interior of Albion’s bosom’.