by FRAÇOISE FLIEDER & ELISABETH DELANGE IN COLLABORATION WITH ALAIN DUVAL & MARTINE LEROY
Papyrus is one of the oldest writing materials in the world. In ancient times, it was produced from the stem of the reed Cyperus papyrus Linne, which was cultivated for nearly 4000 years by the Egyptians on the banks of the Nile. This reed served many purposes: the stem was used as food and in the production of various objects, including carpets, sandals, and boats; the root was employed as a fuel. However, these uses were secondary to the value of C. papyrus L. as a writing material. The oldest papyri date from 3100 BC (blank papyrus discovered in the tomb of Hemaka). Papyrus was used in the papal chancellery up to the 12 century AD. This continuity in time has left the curators of museums with an extremely complex collection, in terms of the writings and languages represented. There are hieroglyphic, hieratic, and demotic writings, Greek and Coptic texts, and even Latin, Aramaic and Arabic documents, to which we can add bilingual writings (mainly Greek and Demotic). These major linguistic families witness not only the long course of history, but also the vast selection of subjects covered by this unique material. Thus, the collection of the Louvre, for example, includes a veritable library in which important historical pieces and true works of art with rich illuminations lie next to repetitive sets of documents and simple texts.
THE HISTORY OF A COLLECTION
Papyrus occupies a special place in the history of the collections of the Department of Egyptian Antiquities of the Louvre.
In terms of number it consists of over a thousand Greek papyri but much more Egyptian ones, among them more than a hundred Books of the Dead. However, these figures do not correlate to the size of many individual items, as certain Egyptian papyrus rolls are 21m long, whilst some of the Greek documents are very fragmented.
The papyrus collection was formed in the 19th century. The first were the large collections acquired by the consuls Salt and Drovetti, and later A.P.Ch. Anastasi: 140 by the latter and 103 by the former. Among them were rare pieces, such as the well-known Papyrus on Astronomy, fragments of poetry from the Iliad, or the Mounir Papyrus dating from Tutmosis III, scrolls of funerary, religious papyri and a large number of legal documents, contracts and letters. The initiators of the collection, who lived at the time when Champollion had just discovered how the Egyptian language worked, already realized that the documents written on papyrus proved to be, not only works of art, but also documents rich in information on the civilization of the Pharaohs. The first entry in Salt's inventory reads as follows, "A long text in a beautiful writing with rubrics and symbolic scenes of great value to the study of Egyptian psychology. The drawing of figures is bold and careful. Perfect preservation." In 1853 the Clot-Bey collection was acquired. It contained pieces of similar value, including the Neferubenefand Hornedjitef scrolls. The first catalogue of the manuscripts was produced by Theodule Deveria1 in 1872 and highlighted the wealth of the collection with more than 400 entries, including an almost complete illuminated series of Books of the Dead.
In the last quarter of the 19th century, the philologists Paul Pierret and Eugene Revillout made several important acquisitions on behalf of the museum, including a large number of written documents, partly limestone tablets and partly papyri with a mixture of fragments of many different languages. A single entry can include up to some one hundred items (for example, E 6846). As Revillout did not have the opportunity of buying exemplary pieces, he continued, with commendable competence, to extend the demotic collections, which were previously poorly represented in the museum, and to enrich the Greek section. He also acquired homogeneous series, such as the Brugsch collection, consisting mainly of objects from Fayum, or the Chester collection, which was acquired in three stages2. These documents are contracts (sales, rents, or marriages). Quite often they are of particular historical value because they include precise dates. However, this specialization in acquisitions was not in accordance with the collection policy of the museum. In 1896 the Museum Council stopped all acquisitions of palaeographic documents and even envisaged their transfer to the Bibliotheque Nationals. From then on, the collection was practically frozen. A few acquisitions were made in the 20th century. Some of them were linked to other objects, which was the case with the Neferubenef Book of the Dead, others completed a set (for example, the Nine Magic Papyri bought in 1995) or filled in gaps, such as the highly decorated papyri from Serimen and Nespakachouty. The most spectacular acquisition was that of the Jumilhac Papyrus in 1945, which is an important mythological document relating the religious legends of an entire region of Egypt at a relatively late period (Fig. 1).
Fig. 1: The Jumilhac Papyrus E 17110 (Ptolemaic period: ca. 140 BC)
It is a special characteristic of the Louvre collection that there was no acquisition of papyri from excavations at the end of the 19' century and, more particularly, in the first half of the 20th century. Apart from the donations of Auguste Mariette, explorer of the Serapeum of Memphis, which included some rare fragments of the Greek poet Alkman, and sacks of fragments from the excavations of Clermont-Ganneau on the island of Elephantine, there have be no real donations from excavations. However, there were some donations given by Egyptologists. They understood the scientific value of the texts they had acquired and were generous enough to offer them to the Louvre. Examples of this kind of acquisition are the Sarcophagus texts, donated by Alan Gardiner and Raymond Weill, the Rames-sides Letters donated by Emile Chassinat, the exceptional Titular of Rameses II donated by Stier, and the Gosset donation of the Pentaour Poem.
The state of preservation of the collection in the Louvre is extremely variable. The early papyri were stored in rolls, often cut into many smaller sheets and then glued onto cardboard supports for better presentation and documentation. Scattered and fragile fragments were repeatedly moved and re-housed, often without any protection, suffering inevitable damage. Certain pieces have been repeatedly restored, some for the better, others for the worse. Finally, the most spectacular pieces were exhibited for many years in the public galleries of the museum, contrary to modern recommendations on preventative conservation.
LIMITS OF KNOWLEDGE
While the palaeography and the reading of a papyrus document enables the Egyptologist to understand its purpose, most papyri cannot be connected to their archaeological context. Only a few papyri have been accurately dated. We can understand why religious and funerary texts, which were destined to accompany the dead for eternity, remain undated, but this is not the case with administrative documents, where we would expect a precise dating. The oldest samples are also the most rare, for example, the Abusir Papyrus, the archives of the Neferirkare temple (Vth dynasty) and the Mounir Papyrus, which described deliveries under Pharaoh Tutmosis III. However, some of the most important series of religious papyri cannot be precisely dated.
The condition of the collection has highlighted the need for restoration, which means the need for prior scientific studies. Restoration automatically implies an understanding of the different materials used in the manufacture of the object. Through close contact with the object during its restoration, research can enlighten the methods of its production. This research combines the approaches of a scientist, a curator and a conservator. It aims to understand the techniques and "recipes" used, to follow the working procedures of the craftsman, to analyse the "ageing" processes of the constituent materials and to reveal what might have been the original function of the object. Hence, it touches on disciplines as diverse as cultural history, botany, physics and the many facets of chemistry.
Even though the literature on the production and restoration of papyrus is quite extensive3-6, many intriguing questions are still unanswered. The following are the most common, which have been posed repeatedly since the first written commentary7, Natural History by Pliny the Elder (lst cent. A.D.), in which he described in detail papyrus production.
• How do the two layers of papyrus stick together? Is it because of alluvium from the Nile7, sugars liberated by the plant8,9, the presence of some sort of glue, such as starch10,11, or the imbrication of the cells provoked by the pressure imposed during the drying process?
• Which part of the stem was used to cut the strips of papyrus7,'12?
• Why are some papyri whiter than others?
• What is the impact of time on papyrus?
In order to answer these questions, we decided to produce our own papyrus and analyse the various organic compounds and minerals found in ancient specimens. We also examined the behaviour of papyrus in various types of accelerated ageing experiments.
production of papyrus used as a writing material
The stems of C. papyrus L. are triangular in cross-section and can reach 4 m long. First, the stems are stripped, and then the pith is cut into strips13. A series of 37- to 45-cm strips, according to the format desired, are laid parallel to each other to make up one layer. A second layer of 10- to 20-cm strips is then laid perpendicularly to the first; this forms the writing surface. The whole is then pressed or beaten, until the sheet of papyrus is completely dry. Scrolls were made by sticking many of these sheets together.
Some researchers have manufactured papyrus7,14,16 and, using their observations, we made some of our own from the stems of C. papyrus L. cultivated in the Museum National d'Histoire Naturelle in Paris. The method described above was used. The papyrus was dried in a press between blotting paper, which was changed regularly. We also tried beating the papyrus in water before the drying procedure. We observed the following.
• The action of the press is sufficient for the adhesion of the two papyrus layers. The addition of glue is therefore unnecessary.
• Strips cut from the lower part of the stem are more translucent and give a better adherence than strips cut from the upper part, which are more opaque.
The colour of the papyrus is related to its thickness. The thinner the papyrus, the quicker it dries, and the whiter the resulting sheet. This can be explained by the fact that C. papyrus L. contains enzymes such as phenol oxidase and lactase, which, in the presence of oxygen, acts as a catalysts for the oxidation of the plant phenols. The monophenols are oxidized into orthophenols, which are in turn oxidized into the corresponding quinones; quinones are coloured compounds. This process is the reason papyrus turns brown on contact with air. When the pith of C. papyrus L. dries, these enzymes are deactivated and can no longer have any action on the plant phenols. This is why, once the papyrus is finished, the combined action of water and oxygen has practically no effect. This is in accordance with what we have observed in the collections of the Louvre, thicker papyri are darker, whereas the thinner ones are much lighter. A brown discoloration can also be induced by beating prior to drying.
analysis of minerals
The mineral analysis was carried out by proton-induced X-ray emission (PIXE) using the AGLAE particle accelerator of the Centre de recherche et de restauration des muse'es de France (CRMF).
The proton beam leaves the accelerator through a kapton window. Because the sample is outside the accelerator, PIXE has the advantage of performing a non-invasive analysis of works of art irrespective of their form or size. At the point of impact of the beam, the object emits X-rays the energy of which is characteristic for the elemental composition of the object. The external beam line of the accelerator comprises a number of different parts17.
• The document is mounted on a support that can be moved in three dimensions and position the zone of analysis correctly within the particle beam;
• a small camera allows observation of the document and its position from the control room;
• two X-ray detectors are used for low- (<5 keV) and high-energy X-rays;
• a helium atmosphere between the object and the detectors permits the detection of X-rays emitted from the light elements, which would be absorbed by air; all elements above sodium can thus be determined quantitatively.
The detectors are calibrated using thin targets of accurately known elemental composition (in mg/cm2).
Given the low penetration of 3-MeV protons into solid materials (a few tens of micrometers), PIXE analysis is particularly well suited to the analysis of thin films, such as inks, miniatures, and drawings 18-21.