Preserving papyrus: caring for 4000-year-old documents

The oldest written papyrus from the British Museum in the exhibition dates from the 12th Dynasty (1985–1795 BC) – these delicate papyri have survived for thousands of years, giving us so much information about life in ancient Egypt.

Papyrus is made from the Cyperus papyrus plant. The stem of the plant is made into sponge-like strips which are overlapped horizontally then vertically, and then pressed together to form sheets. These sheets can be attached together to form rolls for writing. When first made, papyrus sheets would have been strong and flexible, providing a good surface for writing. The presence of water in the earth causes organic materials such as papyrus, textiles or wood, to deteriorate and rot away. Papyrus is mainly made of cellulose, which ages and deteriorates over time, becoming fragile and brittle as it's broken down by hydrolysis (a reaction with water) and oxidation (a reaction with oxygen).

Luckily, the dry Egyptian climate means that papyrus has been able to survive for thousands of years. This lack of moisture also protects papyrus from being affected by microorganisms, like mould, which could consume and destroy the papyrus. In ancient Egypt the inks used for writing were very stable: the carbon black and red haematite (red ochre) aren't soluble in water and aren’t sensitive to light, so the writing can still be read clearly today. 

The way papyri were originally used also affects how well they have survived. For example, books of the dead were high-status, high-quality objects made to be used once, when they were placed with the mummy for burial, so they can sometimes survive in surprisingly complete condition. Other papyri were made to be used repeatedly and sometimes became damaged from handling. You can see evidence of this in the Rhind Mathematical Papyrus, where a patch of papyrus was used to repair damage so that the text could continue to be used for reference. 

Surviving papyri can be fragile and brittle, and generally have problems such as missing areas, tears and other examples of deterioration. These ancient manuscripts must be stored and handled very carefully to preserve them for future generations. At the British Museum, papyri are regularly used for study by visiting scholars, displayed in the galleries, or loaned to museums all over the world for exhibitions.

In the collection, papyri are protected by storing them in mounts, made from two pieces of glass taped around the edges. The papyrus is placed between the pieces of glass and attached with Japanese paper hinges so that the papyrus doesn’t move around. The Japanese paper that we use is very pure and made from long fibres, resulting in a thin and strong material. The glass supports the papyrus over its whole area and makes both sides visible for study, as many papyri have text on both sides. For large papyri the glass enclosure is usually given extra support from a wooden or metal frame. This keeps the papyrus as stable as possible, by avoiding any flexing of the glass.
 

More than 30 papyri from the British Museum collection were conserved for Hieroglyphs: unlocking ancient Egypt. Some needed only a few repairs or improvements to their framing. However, others needed more extensive treatments. Part of the Book of the Dead of Padihorpara needed a lot of conservation before the exhibition. It was adhered to a 19th-century paper backing which was distracting and unevenly coloured brown with watercolour paint. The papyrus was in two sections with a large gap between the pieces, which were not correctly lined-up – making the text confusing to read. The lower section was badly deteriorated with many missing areas, and it was much darker in colour than the upper section –  it had been heavily stained by mummification balm when the rolled papyrus was placed with the mummy for burial. Balms were made from mixtures containing tree resins, plant oils, bitumen and animal fats, and these had covered the lower end of the papyrus roll. You can read more about mummification balm, what it was used for and why in Dr Kate Fulcher’s blog. 

First, I needed to remove the backing paper and separate the lower papyrus fragments. To do this I strengthened the papyrus fragments temporarily with Japanese paper, adhered with conservation adhesive dissolved in acetone. Next, I used water to remove the paper backing. As some of the dark brown staining was soluble in water and acetone, this process also reduced the staining a little, making the text easier to read. As the smaller fragments were so thin and deteriorated, I decided to support each of the fragments with a lining of thin Japanese paper adhered with wheat-starch paste to give strength to the whole area. Next, I examined the fragments to see how the text could be matched between sections. The placement of the fragments was then studied over a light box so that the transmitted light would show if the papyrus fibres matched correctly. Finally, I mounted the papyrus between two pieces of glass and bound the edges with linen tape. The conservation treatment was rewarding as it significantly improved the overall appearance of the papyrus as well as correcting the placement of the fragments so that the text is easier to read.

The Vaucelles papyrus was recently acquired by the Museum as 15 separate fragments. It dates from 670 BC and is written in a very rare script called cursive hieratic. Some of the fragments were in a poor condition with many missing areas where insects had eaten away the papyrus. Previous repairs with Sellotape covered many of the most damaged areas. I treated the fragments individually, first removing the Sellotape and then repairing the papyrus with many small pieces of toned Japanese paper adhered with wheat-starch paste. 

While carrying out the repairs I noticed that the shape of two fragments, and the placement of the text, suggested that they may have originally been joined together as one piece. Papyrus sheets have a strong vertical and horizontal fibre pattern due to how the strips of papyrus were placed when it was made (see image below). So, I examined the fragments together over a light box where the fibre structure could be revealed by the transmitted light – I was delighted to find that the two fragments joined directly together as the fibre pattern matched across both pieces!

As the treatment continued I found more and more joins, eventually discovering an amazing 12 direct joins between the larger fragments, which was very unexpected. To piece together such a long section of text was really exciting, especially as it turned out to be one of the longest surviving cursive hieratic papyri.

Beautiful papyri with drawings and handwritten text give us a personal connection with real people who lived thousands of years ago. The texts cover a multitude of topics, from religion and history to legal matters, literature and personal correspondence. Hieroglyphs handwritten in ink have an immediacy that we can relate to on a human level which brings the people of ancient Egypt to life as we learn about their society and their daily lives.

You can see the papyri Helen worked on, and many more objects connected to the decipherment of Egyptian hieroglyphs in the exhibition, Hieroglyphs: unlocking ancient Egypt, until 19 February.  

Supported by bp