What is a Palimpsest?

If a scribe needed to write a text, they would simply find a less important text, scrape or wash off the old text and write the new text on top. This is called a palimpsest.

As St. Catherine’s monastery was very isolated, it became common practice to reuse old bits of parchment to create new manuscripts. In fact, the monastery has one of the world’s most extensive collections of palimpsests.

In the 19th century, chemical reagents were used to enhance the original text, but this process damaged the parchment. Later, in the early 20th century, ultraviolet light helped researchers distinguish between the different types of inks and the parchment.

More recently, non-invasive technological developments have made it even easier to read the initial script without damaging the actual manuscript. Researchers use multi-spectral imaging to illustrate the differences among the parchment, the ink of the overtext, and the ink of the undertext. With this technique, palimpsests are photographed with 12 different narrow bandwidths of light. When the raw images are combined using digital image processing techniques, usually the underlying script becomes legible.

Some of the most famous palimpsests include unique examples of legal, mathematical, philosophical, and religious texts. A nearly complete text of the Institutes of Gaius, one of the first textbooks on Roman law, was discovered underneath the letters of St. Jerome and Gennadisu. The Sanaa palimpsest is one of the more compelling examples as both the upper and lower texts are copies of the Quran. However, the underwriting did not follow the standard sequence of chapters and was radiocarbon dated to 632–669 CE, making it one of the earliest known Quranic manuscripts. Some palimpsests represent the only known copies of ancient scripts. The Archimedes Palimpsest includes two writings of the Greek mathematician that were previously thought to be lost, and includes the only known Greek copy of another of his books on physics. The manuscript ended up in a Greek monastery in Palestine and was written over with a religious text. There are also double palimpsests, which are overwritten multiple times. A double palimpsest in the British Museum was originally historical annals written in the 5th century, which was then written over by a 6th-century Latin grammatical treatise, then overwritten again with a 10th-century text of St. John Chrysostom, in Syriac.

Among the many palimpsests at St. Catherine’s monastery is the Syriac Sinaiticus or Codex Sinaiticus Syriacus, the oldest Syriac copy of the gospels, from the 4th century. It was overwritten by biographies of female saints and martyrs from 697.

There are more than 160 known palimpsest manuscripts in the collection of St. Catherine’s monastery, including classical, Christian, and Jewish texts in at least ten languages (Greek, Syriac, Georgian, Arabic, Christian Palestinian Aramaic, Latin, Caucasian Albanian, Armenian, Slavonic, and Ethiopic) and several ancient scripts.

The Sinai Palimpsests Project, a collaboration between St. Catherine’s Monastery and more than 20 scholars and experts, is on a mission to reveal the hidden history of these manuscripts. The project has published an online digital library of palimpsests with a searchable catalog.

Some of the preliminary finds of the project include:

• Erased text in Ethiopic and Latin, demonstrating the centrality of the Monastery of Saint Catherine in the world of medieval Christendom.
• The earliest surviving copies of several texts from the Hippocratic corpus, demonstrating the level of erudition in the monastery.
• Discovery of two previously unknown classical Greek medical texts.
• A large number of texts written in Christian Palestinian Aramaic, many of them previously unattested.
• The identification of a folio from a work of the ancient physician Galen, in Syriac translation, which demonstrates the Sinai provenance of a manuscript that is otherwise dispersed among collections of Rome, Harvard, Paris, and a private U.S. collector.
• A significant number of pages written in different variants of Greek majuscule of the 4th to the 9th century, which are contributing to a more nuanced understanding of the development of Greek script over time.
• Many double palimpsest folios, as some parchment sheets were reused multiple times.