COPYING, COMMONPLACES, AND TECHNICAL KNOWLEDGE: THE ARCHITECT-ENGINEER AS READER Alexander Marr I Recent work on the history of technology has drawn attention to the importance of manuscripts and, in particular, drawings for the design, construction, comprehension, and use of machines in the Renaissance and Early Modern period.1 Documents such as the workshop drawings of Antonio da Sangallo or the extensive extant papers of Heinrich Schick- hardt are now finding a place alongside better-known printed works, such as the ‘theatres of machines’ by Ramelli, Besson, and Bachot.2 Yet com- paratively little is known about the book ownership and reading habits of those artisans involved in the processes of machine design, construc- tion, and implementation. The present essay seeks to shed new light on these subjects, through an examination of an important – but somewhat neglected – manuscript compilation of text and images on technical top- ics (ranging from practical mathematics to building), made in the early seventeenth century by the French architect-engineer Jacques Gentillâtre (1578–c. 1623).3 To date, this manuscript has been discussed exclusively within the context of the theory and practice of architecture, yet the diversity of subjects with which it is concerned (notably the numerous uses to which machines may be put) demands that the document be 1 See e.g. Lefèvre W. (ed.), Picturing Machines, 1400–1700 (Cambridge, MA-London: 2004). 2 See the useful table of ‘Prominent Sources of Early Modern Machine Design’ in Lefèvre, “Introduction to Part I”, in idem, Picturing Machines 13–15. An important addition to this table is Ambroise Bachot’s theatre of machines: Gouuernail (Melun: 1598). On Schickhardt, see Lorenz S. – Setzler W., Heinrich Schickhardt: Baumeister der Renaissance – Leben und Werk des Architekten, Ingenieurs und Städteplaners (Stuttgart: 1999). 3 Bibliothèque Nationale de France, Manuscript Français 14727, currently (and incor- rectly) catalogued as an anonymous ‘Manuel d’un ingénieur-architecte de la première motié du XVIIe siècle’. 422 alexander marr scrutinized from a wide range of alternative angles.4 In particular, evi- dence internal to the manuscript suggests that it should be considered within three key Early Modern contexts: the reception and circulation of technical knowledge via printed books; copying practices; and the adapta- tion and application of the commonplace method by technical practitio- ners. Gentillâtre’s manuscript is thus an ideal vehicle for the examination of how and to what ends a particular type of artist read printed books in the Early Modern period. The importance of fifteenth-century technical treatises in manuscript (such as those by Mariano Taccola and Francesco di Giorgio Martini) has long been established, yet relatively little work has been undertaken on later manuscripts, such as Gentillâtre’s, concerned with the practice and materials of engineering.5 In particular, manuscript compilations of cop- ied extracts from printed books on technical subjects, which I will refer to here as ‘copybooks’, have been almost entirely neglected, despite the fact that a host of such manuscripts survive from the sixteenth and seventeenth centuries. To take just one early seventeenth-century Italian example, drawn from the domain of military engineering, the Biblioteca Oliveriana in Pesaro contains several copybooks on fortification and ballistics com- piled by the Pesarese Captain Valerio Pompei, containing extracts from Gabriello Busca’s Della architettura militare (1601), Luigi (Luis) Collado’s Pratica manuale di artigleria (1586), and Bonaiuto Lorini’s Le Fortificationi (1597).6 Copybooks such as Pompei’s, which are frequently an admixture 4 The variety evident in the manuscript is of fundamental importance for the under- standing of machines and those individuals involved with their design, manufacture, and implementation in the Early Modern period. While it is true that the professions of archi- tect, fortifications expert, instrumentalist, and machine designer are defined with increas- ing clarity throughout the course of the sixteenth century, there are many examples of professionals practising all of these disciplines. Gentillâtre’s manuscript shows clearly that all four were part of the same set of practices; in this document, models for machines, architecture, instruments, and fortifications are placed side by side, grouped together as interconnected mathematical arts. 5 For Taccola and Francesco di Giorgio, see e.g. Taccola Mariano, De machinis: The Engineering Treatise of 1449, ed. G. Scaglia, 2 vols. (Wiesbaden: 1971); and Mariano Taccola and his Book ‘De Ingeneis’, ed. F.D. Prager – G. Scaglia (Cambridge, MA: 1972); Giorgio Mar- tini Francesco di, Trattati di architettura ingegneria e arte militare, ed. C. Maltese, trans. L. Maltese Degrassi, 2 vols. (Milan: 1967); Fiore F.P. (ed.), Francesco di Giorgio alla corte di Federico da Montefeltro, 2 vols. (Florence: 2004). Recent studies of the manuscript culture of Renaissance and Early Modern engineering include Fiocca A. (ed.), Giambattista Aleotti e gli ingegneri del Rinascimento (Florence: 1998); Fiocca A. – Lamberini D. – Maffioli C. (eds.), Arte e scienza delle acque nel Rinascimento (Venice: 2003). 6 Biblioteca Oliveriana, Pesaro (BOP hereafter), MS 966, “Della Pratica manuale di Arteglieria del [. .] Sig[nor]e Luigi Collado”; MS 997, Pompei V., “Fortificationi”; MS 1097, .