Independent self-taught scholars. These twin sisters were born on 16 April 1843 at Irvine, Ayrshire. Both were widowed early on in their marriages, and devoted much of the rest of their lives to scholarship. They wrote under their married names, A. S. Lewis and M. D. Gibson. Agnes was concerned primarily with Syriac, publishing many new texts in the series Studia Sinaitica (1–12; 1894–1907), while Margaret concentrated more on Christian Arabic texts, which she published in Horae Semiticae (1–11; 1903–16), though she also edited and translated the Didascalia (1903) and Ishoʿdad of Merv’s Commentaries on the Gospels and Acts. Thus Agnes provided the Catalogue of the Syriac mss. at St. Catherine’s Monastery (1894), and Margaret that for the Arabic ones (1894). (Impressed by their knowledge of Modern Greek, the Librarian gave them access to the mss.) Among Agnes’ important editions are Select Narratives of Holy Women (1900), representing the upper text of the ‘Sinaiticus’ ms. of the Old Syriac Version of the Gospels, Apocrypha Syriaca (1902), and several Christian Palestinian Aramaic texts, both biblical and hagiographical. Together the two sisters edited the Palestinian Syriac Lectionary (1899) and a collection of Christian Palestinian Aramaic palimpsest fragments from Geniza mss. (1900). The mss. they acquired in Cairo were left to Westminster College, Cambridge.