“Unfolded Worlds: Allegory, Alchemy, and The Image As Structure of Knowledge In Early Modern Northern European Scientific Books” focuses on alchemical book illustration. It places the corpus of alchemical images 1450-1650, found as both print and manuscript in significant British collections, within the broader scope of the intellectual history of Northern European books. I argue that alchemical book images do the essential work of making humanist arguments about matter as allegory, and transmitting those arguments across space and time. These images simultaneously serve as sources of beauty, codes for laboratory procedures, and statements about the order of the universe and the position of man in it. Specifically, my first section focuses on Elias Ashmole, antiquarian, scientist and founding member of the Royal Society, and in particular on his alchemical and botanical manuscripts and their relationship to one another. In addition to my previously published work on the Ripley Scrolls, mysterious 25-foot long encoded alchemical symbolic manuscripts, I also draw out a new Neo-Platonic reading of embedded and recovered knowledge in alchemical images. My second thesis section focuses on Glasgow MS Ferguson 6, whose illustrations reflect the tendency of alchemical material in particular to draw both text and images back from the print corpus into manuscript again. Here I discuss the intentional use of manuscript as a way of conveying meaning and change outside the basic copied textual material. I also propose a framework for the alchemical miscellany not as a hodgepodge, but as a carefully selected whole within a general epistemology that frames the acquisition of secret knowledge as physical, mental, and spiritual desire. I also address, in my third chapter, garden books and alchemical books taken together within the sphere of an Early Modern library. The illustrated borders of Elias Ashmole’s published print anthology, the Theatrum Chemicum Brittannicum, and Bodleian MS Ashmole 1423, a manuscript formula book with unique botanical-themed illustrations and intriguing garden fauna, form key case studies. This chapter discusses the relationship between antiquarianism and the materiality of the book, and that of the garden and garden literature, in light of 17th century conflicts and ideas about how to create a more perfect universe in light of man’s ultimately fallen state. The role of the archive and garden as salvific technology is connected to alchemical book illustration as a locus of these intersecting beliefs and ideas, all within a period of ecological change and growing awareness of both the botanical and chemical processes of nature. Finally, my last thesis section draws these themes together, employing them in a study of Michael Maier’s Atalanta Fugiens. This emblem book, printed by the house of Merian and De Bry, references an account of the Palatine wedding procession and the designs for the palace garden at Heidelberg by Salomon De Caus. I argue that this book is a means of reading alchemical secrets embedded within the Hortus Palatinus and the broader world, and that it also addresses essential questions about the idea of re-creating a lost Edenic paradise, universal languages of truth, and the interconnectedness of text, collection, image, textile, horticulture, dance, and song in the Early Modern learned worldview. In viewing the Ripley Scrolls, the Theatrum Chemicum Brittannicum, MS Ferguson 6, and the Atalanta Fugiens, among many other books in context, my doctoral thesis connects these key cases with reference to period literary works. I raise new and questions about the relationship between images, language, and meaning creation in Early Modern scientific books.