The momentous accomplishment of Gutenberg's first printing of the Bible was preceded by a number of necessarily experimental publications which developed the technique of printing with moveable type. This fragment, printed using the type of the 36-line Bible, is a relic of those trials. The text is part of a Latin grammar written by Donatus, who was the teacher of St. Jerome. His grammar was one of the most popular teaching aids during the medieval period, and Gutenberg seems to have found it advantageous to publish many editions of it, not only as practice but also as a source of much needed revenue. There are twenty-four known editions of the text in Gutenberg's earliest type, all preceding the famous Bible. Described by earlier scholars as a "Pfister imprint," dated ca. 1460, recent investigations indicate that this fragment belongs with Gutenberg's work, probably dating not later than 1452.