Primary Contributors:

Emma Grummitt and Philip Beeley, with EMLO and the Cultures of Knowledge research project

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The Cipher Books

In 1653 John Wallis transcribed several copies of a collection of ciphered letters which he had decoded during his time working for parliamentary forces in the 1640s. There are three extant copies of the manuscript entitled ‘A Collection of Letters and other Papers, in Ciphar, during the late warres in England’, all of which are held currently in the Bodleian Library at the University of Oxford. Two of these copies are in Wallis’s own hand and one is in an unknown hand.

The letters appear to have been curated as a learning tool to teach readers about the composition of particular civil war codes. The collection also serves as a monument to Wallis’s mathematical prowess, exhibited by his solutions to many complex numerical ciphers. Despite the politically turbulent climate of 1653, and the relative contemporaneity of his sources, Wallis defends his sensitive collection in his preface ‘To the Reader’ on two grounds. First, he often deliberately chooses not to decode the specific details of the people and places mentioned in his collection ‘as not being at all material to my present purpose’. Secondly, he hopes that by exposing the flaws in these ciphers he may enable future generations to ‘conceive some other that may exceed these’. As a result, the letters do not tend to reveal groundbreaking intelligence, but rather provide invaluable insights into the academic fields relating to ciphers and mathematics.

Partners and Additional Contributors

This catalogue was produced by Emma Grummitt as part of a practical placement working on Early Modern Letters Online [EMLO] facilitated by the MSc in Digital Scholarship at the University of Oxford. The catalogue was produced in collaboration with Dr Philip Beeley, who has done extensive work on the Cipher Books of John Wallis (for full details, see the Bibliography below).

Key Bibliographic Source(s)

Beeley, P., ‘Documenting the Secret Art: The Oxford Mathematician John Wallis and his Manuscript Book of Ciphers’, Bodleian Library Record, no. 37 [forthcoming, 2025].

Contents

The first copy, MS. e Musaeo 203, contains fifty-two copies of deciphered letters in Wallis’s own hand all dated between 1641 and 1653. The second copy, MS. Eng. misc. e. 475, also in Wallis’s hand, contains fifty-three deciphered letters, with the last additional letter dated 1658. This copy also supplies extra information on the context of the letters in its contents page, which differs from MS. e Musaeo 203. The third copy, MS 19336, acquired by the library in 2020, is in an unknown hand and is an almost exact copy of MS Eng. misc. e. 475.

Each copy is prefaced with Wallis’s epistle ‘To the Reader’, describing his reasoning behind forming the collection, but only MS. Eng. misc. e. 475 is bound with biographical accounts written by his descendants. The letters, which were mainly written by royalist supporters, were intercepted by parliamentary forces and then given to Wallis to decipher. They largely cover the Presbyterian plot of 1649–51, the Treaty of Breda, and royalist interactions with foreign powers such as the Dutch, the French, and the Scottish.

Scope of Catalogue

This catalogue provides contextual information only when it has been provided in the manuscript collection, either explicitly, or implicitly through the contents of the letters. This is because key metadata are frequently missing; fields such as recipient, author, date, and location are often not decoded. Yet, because this information was not necessarily the main focus of the original collection, a decision has been made to retain these blank fields. Therefore, the historical context provided is limited. Instead, in the belief that this is the primary focus of the original collection, detailed notes are provided on the composition of the cipher used in each letter, drawing on a categorization tool created by Emma Grummitt (published on the introductory page ‘Early Modern Cipher Correspondence in EMLO‘) in the course of her Practicum work with EMLO.

Further resources

For further details on cipher letters and on this genre more broadly, see ‘Early Modern Cipher Correspondence in EMLO: a “starter” collection’.

Launch Catalogue