At the heart of this chapter is a reading of Merlin’s glass – a perspectival object that crystallises new perspectives on the speculative poetics of the early modern geographical imagination. The chapter thinks about how to gauge the changing scales of Britomart’s journey by reading her quest alongside the spatial arts of cosmography and chorography, and looks back to the earlier readings of Cuningham’s Cosmographical Glasse and Waghenaer’s Mariners Mirrour. In seeking out the maker of her vision, Spenser’s lady-knight makes the transition from speculative armchair traveller to practical wayfarer, thus drawing together multiple modes of spatial representation in Spenser’s poem. In its discussion of spatial rhetoric, this chapter acts as a bridge between the initial focus of the book on archetypes, expectations, and genres, and the emerging focus of the second half of the study in shifting, but specific, types of environments. In particular, the movement towards Merlin’s cave at Maridunum introduces a coastal setting that both anchors and destabilises Spenser’s fiction-making and offers a vital example of Spenser’s increasingly fraught handling of the relationship between spatial forms and desire.