The date at which this important change was introduced into Egyptian writing has been a matter of much dispute. If it is correctly attributed to Christian influences, the new alphabet must have been coeval with the birth of a native Christian literature in Egypt. The earliest extant remains of such a literature, to which we can fix a date with any certainty, are the Epistles of St. Antony (who was born about the middle of the third century) to Athanasius and Theodore; but, as we shall see presently, one or both of the two principal Egyptian versions must have been already in common use at this time. Indeed, if the date assigned to a recently discovered writing be correct, the introduction of the new character was much earlier than this. On the back of a papyrus in the British Museum, containing the Funeral Oration of Hyperides, is a horoscope in Greek and Egyptian, the latter written in Greek characters, with the additional six letters almost, though not quite, identical with the forms in the ordinary Coptic alphabet. Mr. C. W. Goodwin, who describes this important document in Chabas, “Mélanges Égyptologiques,” 2me série, p. 294 sq., and in the “Zeitschrift für Aegyptische Sprache,” vi. p. 18 sq., February, 1868, calculates (though he does not speak confidently) that it is the horoscope of a person born A.D. 154(95). Any account of the Coptic dialects must start from the well-known passage in the Copto-Arabic grammar of Athanasius, bishop of Kos in the Thebaid, who flourished in the eleventh century. “The Coptic language,” he writes, “is divided into three dialects; that is to say, the Coptic dialect of Misr, which is the same as the _Sahidic_; the _Bohairic_(96), which gets its name from the province of Bohairah; and the _Bashmuric_ in use in the region of Bashmur. At the present time only the Bohairic and Sahidic continue to be used. These different dialects are derived from one and the same language” (quoted in Quatremère, Sur la Langue &c., p. 20 sq.). For the present I will dismiss the Bashmuric, as it will require further investigation hereafter. The remaining two, the Bohairic and Sahidic, were the principal dialects of the language, being spoken in Lower and Upper Egypt respectively; and are largely represented in extant remains of biblical and ecclesiastical literature(97).