Palimpsest (παλίμψηστος), a term applied to manuscripts in which the original text has been scraped or washed away, in order that another text may be inscribed in its place. As the term properly implies scraping, it must have originally been applied to such materials as leather, wax, or parchment, and only by analogy to papyrus, which could be washed, but not scraped. The term seems to occur first in Catullus (22. 5); cf. Plut.Mor. 504 d, 779 c, where it is treated as synonymous with ἔκπλυτος, ‘washed out’. When parchment was scarce (especially, it seems, about the 9th cent. in western Europe) early manuscripts were not infrequently treated thus; and since the removal of the original writing was seldom complete, valuable texts of the Bible, Cicero's De re publica, Plautus, Gaius (2), Licinianus, etc. , have been recovered from such palimpsests. In the Byzantine world the shortage of writing material was often severe, especially in the Italo-Greek areas. An important palimpsest of early date has yielded some fragments of Euripides' Phaethon; still more significant is the codex from which J. L. Heiberg recovered an unknown treatise of Archimedes. This codex now proves to contain substantial fragments of two speeches by Hyperides and part of a previously unknown commentary on Aristotle's Categories. See also palaeography, Introduction.