As the background of a forthcoming PhD thesis, every manuscript baptismal ordo that is registered under the Baptism label of our Ceremonies menu has been processed and uploaded from the earliest Old Latin service books of the 7th and 8th centuries up to the dawn of the printing press period. The regular method was providing the rubrics in full and the prayers with opening and ending words, but rare or philologically very variable texts were entered in extenso. The sample contains now about 200 sources from all of Europe, including the pre-baptismal rites like the scrutinies or the consecration of the baptismal font.
The result can be studied from the perspective of both the text material and the liturgical functions. Incipits that appear in any of the ordines have been linked to standard items, providing the entries of a provisional edition of the corpus of Latin baptismal texts in the Middle Ages (see the full list here). Thus, the research facilities of Usuarium yield statistics and maps, enabling us to evaluate the significance, historical range, and geographical coverage of each formula. Liturgical functions have been tagged with a standard terminology of modules such as 'salt', 'insufflation', 'catechumen oil', etc. (see the full list here). With the help of these, functionally analogous sections of different clusters or ordines can be compared.
For instance, while the oration Deus immortale praesidium is a universal choice, Te deprecor is typical to German lands (though already to the early Poitiers Pontifical), and the great exorcism Deprehensae sunt is a rare Visigothic feature, surviving in some early Catalonian codices as well. Again, while the orations and formulas accompanying the administration of salt are almost ubiquitous, the variation of Gospel passages is highly informative, and the handing over of the candle is in itself a phenomenon missing form certain areas.