Concertina-Fold Almanacs

Concertina-fold almanacs are a kind of book defined by structure and content. They are made of oblong parchment sheets folded first lengthwise to form a narrow strip and then in a zig-zag or accordion pattern to create a portable packet. Fully folded, concertinas can be paged through like a codex, but—a little like a pop-up book—their pages can also be opened to reveal more information within. Cuts in the parchment allow interior content to be accessed without unfolding an entire sheet. Extant examples suggest that concertina-fold almanacs were a late medieval (1389 and after), Northern European phenomenon. That said, the surviving twenty-nine concertina manuscripts vary significantly in date, place of origin, size, quality, and content. Yet all are almanacs, that is, they contain calendars and other materials loosely related to time. Indeed, the format seems to have been contrived specifically for this use and, after its invention, deemed to be uniquely suited to this task. Their study thus reveals the pressures that temporal content put on the codex and the expressive possibilities afforded by folding.

I’ve been researching concertina-fold almanacs since 2021 alongside Drs Sarah Griffin and Kathleen Doyle. Together we are writing a union catalogue that will summarize what we’ve learned about these unusual books and include descriptive entries of all 29 manuscripts. Travel and photography for the project has been underwritten by grants from the British Academy’s Neil Ker Memorial Fund (2021–22), Bibliographical Society (2022), and the University of Edinburgh (2022–24).

Our work to date has informed the exhibition Unfolding Time: The Medieval Pocket Calendar curated by Griffin and on view at Lambeth Palace Library from 14 February to 15 May 2025. The exhibition was made possible by the National Library Heritage Fund.

Publications
with Sarah Griffin and Kathleen Doyle. Concertina-Fold Almanacs: A Catalogue [expected completion 2025]

‘A Wrinkle in Time: The Structural Significance of a Fourteenth-Century Folded Almanac’ [expected completion 2025]

Nos. 164–5, in Lisa Fagin Davis et al. (eds.), Beyond Words: Illuminated Manuscripts in Boston Collections (Chicago: University of Chicago Press, 2016), 201–206.

‘Making Knowledge Portable: The Zodiac Man, in the Context of Folded Medical Almanacs‘ (MA, The Courtauld Institute, 2007).

Presentations
‘A Wrinkle in Time: The Structural Significance of a Concertina-Fold Almanac’
Kress Foundation Art of the European Book Lecture, Rare Book School, University of Virginia, 25 July 2022

with Kathleen Doyle and Sarah M. Griffin, ‘Time Unfolded: Cataloguing Concertina-Fold Almanacs’​
The Book Print Initiative, School of Advanced Study, University of London, 24 February 2022

with Sarah Griffin, ‘Time Unfolded: The Rashleigh Calendar and Medieval Concertina-Fold Almanacs’
Kresen Kernow (‘Cornwall Centre’), 13 January 2022

‘A Wrinkle in Time: Fold and Form in a 14th-century Computus Manuscript’
Hooking Up, Schoenberg Symposium of Manuscript Studies in the Digital Age, University of Pennsylvania, 21–23 November 2019

‘“Walking 500 Winters”: Picturing the Time between Planets in a Folded Almanac’
Medieval Academy of America Annual Meeting, 12–14 February 2015

Conference Sessions
‘The Concertina-Fold Book, Across Premodern Cultures’ (Co-organiser with Sarah Griffin)
International Medieval Congress, University of Leeds, 5 July 2023. Supported by an ICMA Kress Travel Grant SoFCB Funds