Studies of manuscript culture and social authorship that play the myth of “spontaneous overflow” off against detailed histories of production and circulation have neglected the business of copying. Here I explore the significance of fair-copy transcription to the composition of the dream of the Arab—an allegory of poetic power and vulnerability that critics have failed to link to the Wordsworth household’s practices of textual production, reproduction, and preservation. In the process, I revalue Dorothy Wordsworth’s writing—discussed by critics in its own right and as a stimulus for William’s—by considering her collaboration with Mary Wordsworth in “writing out” Prelude MS. M, in the 1804 collection for Coleridge to take abroad, as William was writing the dream. Manuscripts reveal, within the canonical dream of poetic immediacy, a historical drama of mediation involving the time-bound hopes and anxieties of multiple agents, the physical vulnerabilities of verse, and the constraints of the codex format. They authorize a reading of the Arab grounded in the collective material labor of poetic making and the historical conversion of the poem’s addressee and auditor into a postal addressee and reader.