papyrology, the decipherment and elucidation of anything written on papyrus, and the study of the papyrus roll as a form of book. For the manufacture and uses of papyrus see BOOKS AND WRITING 2. Most papyri discovered in modern times come from Egypt where the rainless climate favours their survival. Serious excavations began in the nineteenth century, and at Oxyrhynchus in particular. The earliest papyrus book we have, the Persae of Timotheus, dates from the fourth century BC. Since many of the papyri are of school texts, and the education available was the traditional Greek one (Egypt was conquered by Alexander the Great in 332 BC), more than half of the several thousand surviving literary papyri are of Homer. Of the rest, fragments of works hitherto unknown slightly outnumber the fragments of works already familiar. New texts discovered include several plays of Menander (mostly incomplete), much of Bacchylidēs, some poems of Sappho, Pindar, and other lyric poets, much of Callimachus, the mimes of Herodas, the Ichneutae of Sophoclēs, and several other sizeable fragments of tragedy; and, in prose, Aristotle's Constitution of Athens, the Hellenica Oxyrhynchia (a history continuing that of Thucydides), and several speeches of Hypereidēs. Other papyri contain fragmentary scientific and medical texts, and works on astrology and magic, important as social documents. Discoveries of Christian literary papyri have been equally important, adding further testimony to works already known, most valuably in the case of the New Testament text, and revealing hitherto unknown works, for example the Sayings of Jesus (part of the Gnostic Gospel of Thomas).
Most of the papyri discovered, however, are not literary but documentary: private letters and accounts, legal and administrative documents. A great deal has been learnt from these about the Greek language at various periods, in its most educated and in its semi-literate forms; in particular, the language of contemporary documents has thrown new light on the syntax, vocabulary, and idiom of the New Testament.
Latin papyri have been found in Egypt and a few other places but are comparatively rare. Most date from after the late third century AD, when the emperor Diocletian opened up Egypt, making it equal in status to the rest of the empire and encouraging all the eastern provinces in the use of Latin. Nearly all papyrus fragments of Latin literary texts belong to prose works, but there are important papyri of Juvenal and of Terence's Andria. Some fragments of Christian texts have been found, including one of a trilingual phrase-book in Greek, Coptic, and Latin, presumably of use to those intending to visit the monasteries.