Image by FarÂrin Abbott/SLAC, via Flickr ComÂmons
Long before humanÂiÂty had paper to write on, we had papyrus. Made of the pith of the wetÂland plant CypeÂrÂus papyrus and first used in ancient Egypt, it made for quite a step up in terms of conÂveÂnience from, say, the stone tablet. And not only could you write on it, you could rewrite on it. In that sense it was less the paper of its day than the first-genÂerÂaÂtion video tape: givÂen the expense of the stuff, it often made sense to erase the conÂtent already writÂten on a piece of papyrus in order to record someÂthing more timeÂly. But you couldÂn’t comÂpleteÂly oblitÂerÂate the preÂviÂous layÂers of text, a fact that has long held out promise to scholÂars of ancient hisÂtoÂry lookÂing to expand their field of priÂmaÂry sources.
The decidÂedÂly non-ancient soluÂtion: parÂtiÂcle accelÂerÂaÂtors. Researchers at the StanÂford SynÂchroÂtron RadiÂaÂtion LightÂsource (SSRL) recentÂly used one to find the hidÂden text in what’s now called the SyrÂiÂac Galen Palimpsest. It conÂtains, someÂwhere deep in its pages, “On the MixÂtures and PowÂers of SimÂple Drugs,” an “imporÂtant pharÂmaÂceuÂtiÂcal text that would help eduÂcate felÂlow Greek-Roman docÂtors,” writes AmanÂda SolÂlÂiÂday at the SLAC NationÂal AccelÂerÂaÂtor LabÂoÂraÂtoÂry.
OrigÂiÂnalÂly comÂposed by Galen of PergÂaÂmon, “an influÂenÂtial physiÂcian and a philosoÂpher of earÂly WestÂern medÂiÂcine,” the work made its way into the 6th-cenÂtuÂry IslamÂic world through a transÂlaÂtion into a lanÂguage between Greek and AraÂbic called SyrÂiÂac.
Image by FarÂrin Abbott/SLAC, via Flickr ComÂmons
Alas, “despite the physician’s fame, the most comÂplete surÂvivÂing verÂsion of the transÂlatÂed manÂuÂscript was erased and writÂten over with hymns in the 11th cenÂtuÂry – a comÂmon pracÂtice at the time.” Palimpsest, the word coined to describe such texts writÂten, erased, and writÂten over on pre-paper mateÂriÂals like papyrus and parchÂment, has long since had a place in the lexÂiÂcon as a metaphor for anyÂthing long-hisÂtoÂried, mulÂti-layÂered, and fulÂly underÂstandÂable only with effort. The StanÂford team’s effort involved a techÂnique called X‑ray fluÂoÂresÂcence (XRF), whose rays “knock out elecÂtrons close to the nuclei of metÂal atoms, and these holes are filled with outÂer elecÂtrons resultÂing in charÂacÂterÂisÂtic X‑ray fluÂoÂresÂcence that can be picked up by a senÂsiÂtive detecÂtor.”
Those rays “penÂeÂtrate through layÂers of text and calÂciÂum, and the hidÂden Galen text and the newÂer reliÂgious text fluÂoÂresce in slightÂly difÂferÂent ways because their inks conÂtain difÂferÂent comÂbiÂnaÂtions of metÂals such as iron, zinc, merÂcury and copÂper.” Each of the leather-bound book’s 26 pages takes ten hours to scan, and the enorÂmous amounts of new data colÂlectÂed will preÂsumÂably occuÂpy a variÂety of experts on the ancient world — on the Greek and IslamÂic civÂiÂlizaÂtions, on their lanÂguages, on their medÂiÂcine — for much longer thereÂafter. But you do have to wonÂder: what kind of unimagÂinÂably advanced techÂnolÂoÂgy will our descenÂdants a milÂlenÂniÂum and a half years from now be using to read all of the stuff we thought we’d erased?
RelatÂed ConÂtent:
Try the OldÂest Known Recipe For ToothÂpaste: From Ancient Egypt, CirÂca the 4th CenÂtuÂry BC
Learn Ancient Greek in 64 Free Lessons: A Free Course from BranÂdeis & HarÂvard
IntroÂducÂtion to Ancient Greek HisÂtoÂry: A Free Online Course from Yale
Based in Seoul, ColÂin MarÂshall writes and broadÂcasts on cities and culÂture. His projects include the book The StateÂless City: a Walk through 21st-CenÂtuÂry Los AngeÂles and the video series The City in CinÂeÂma. FolÂlow him on TwitÂter at @colinmarshall or on FaceÂbook.