Dating to c.1383-1415, this curious medieval almanac is one of the oldest items in the Royal Society collections. It is a single, folded parchment manuscript. On one side is an astronomical calendar and illustrated agricultural almanac showing occupations to be undertaken under the different signs of the zodiac. On the other side is a perpetual calendar showing ecclesiastical festivals, adorned with figures of kings and saints.

Surviving medieval almanacs are rare and most examples are medical. The Royal Society’s almanac is particularly unusual as it is a largely pictorial document that could have been used by the illiterate labouring classes. It provides valuable insight into the astrological reasoning that informed medieval agricultural practice, and into the methods of knowledge dissemination amongst a class that is not often represented in the written record. It includes an unusual cipher system, which scholarly analysis suggests is only known in one other surviving manuscript in the UK.

Due to its fragility and complex folded format, the almanac cannot currently be safely accessed by researchers. Conservation will stabilise the manuscript and complementary preservation provisions, such as improved storage, reading stand and handling guidelines will make it possible for researchers to consult whilst also safeguarding its long-term survival. The conservation work will be informed by a new analysis of the manuscript by ‘Team Pigment’ of Durham University. We hope Professor Beeby and his pigment team will also be able to use their spectral imaging expertise to reveal lost content. I am particularly excited to see if they can illuminate the missing zodiacal figure for December, rubbed away over time and through use.

Digital access forms a key part of the long-term preservation plan for our almanac. Once it is cleaned and repaired, high quality digital images will be made available on the Royal Society Picture library. To fully convey the complex folding format and 3-D nature of this object we also plan to make a video. This video will chiefly serve to demonstrate the format of the manuscript, but will include commentary to highlight the conservation work done, and the historical significance of the document and will bring it to a wider virtual audience.