The differences between the Kerver Books of Hours that are kept at Portland State University and at Mt. Angel Abbey: https://www.mountangelabbey.org/ms0078/ reflect a number of important points of difference.

These two Kerver incunabula seem to follow the general layout of most Books of Hours, which is: I. Calendar, II. Gospel Lessons, III. Hours of the Virgin, IV. Hours of the Cross and Hours of the Holy Spirit, V. Obsecro Te & O Intemerata, VI. Penitential Psalms & Litany, VII. Suffrages (of the saints), and VIII. Office of the Dead. Looking at the first few pages of the two, both have general liturgical calendars for religious feast days, and both have borders surrounding the text, though this is where the similarities seem to end between the two.

In the Mount Angel incunabulum, we see that it begins with a general layout of the books of hours and even includes the year it was printed. This is followed by an almanac and then the liturgical calendar. Whereas in the Kerver incunabulum at Portland State University this same section seems to cover more pages of text block than that of its Mount Angel counterpart. It is then followed up by a more detailed almanac that has an image on the upper part of the page, and text on the lower part of the page that seems to tell some general day to day information in it. It was then followed by different charts and tables, such as a list of liturgical feasts and the lunar calendar. The presence of the lunar calendar was probably for the calculating of the Solemnity of Easter as well as to keep track of the progression of the year.

Some very interesting differences appear in the texts at the bottom of the liturgical calendars. The text in the Mt. Angel Abbey Kerver appear to be little quatrains in French rhyme, most of them talking about wine. Each quatrain has as many syllables as there are days in a month, and that helps one remember the main saints’ days because of the common first syllable (in red in the Mt Angel Kerver incunabulum).¹ Therefore, these poems are here to help the reader remember the main saints of the calendar. This text not is found in the Portland State incunabulum. The text block at the bottom of the Portland State Kerver liturgical calendar in the beginning of the incunabulum, but not in the Mount Angel Kerver, is different in terms in that it appears to be medical advice.

Imagery offers another key feature to these incunabula, dividing sections in a text, by separating different feasts and hours of prayer. This use of imagery as a text divider can be found in both Kerver incunabula. The full-page image marking the feast of the Visitation (folio h.2 of the Portland State Kerver incunabulum and folio d.1 of the Mt. Angel Kerver incunabulum) presents both the similarities and the differences of the incunabula. In the Mount Angel Kerver incunabula some key features include that the scene is during the night hours, there are angels present, the halo is around the Blessed Virgin Mary’s head, it takes up only a portion of the page and is followed by a short block of text, Elizabeth is kneeling, and the Blessed Virgin Mary is more dressed like a nun.

These features differ from the Portland State Kerver incunabulum in which we see that the scene is set during the during the day, the absence of angels, a halo above the Blessed Virgin Mary’s head (versus around), that it takes up the entire page, Elizabeth is standing, and the Blessed Virgin Mary is in different attire. Also, though we do not know who the artist was for the engravings in the Mt. Angel Kerver incunabulum, the artists who did the engravings in the Portland State incunabulum was the Master of the Très Petites Heures d'Anne de Bretagne and Jean Pichore.

Because of Thielman Kerver printing these two incunabula from different years of his occupational journey as a printer, some framing and layout options that are different from each other. For instance, in the beginning of the Mount Angel incunabulum there seems to be a lengthy prayer at the end of the liturgical calendar, whereas in the Portland State incunabulum this is not present.

Another thing to note is that there are some feast days located in the liturgical calendar in the Portland State Kerver that are specific for the Northern Spanish region of Catalan but absent in the Mount Angel Kerver. Since these saints are connected with Catalonia, perhaps the book was geared for that market. This hypothesis is further supported by the unusual inclusion of the excerpt in Spanish from the Book of Revelations/Apocalypse according to St. John, on folio t.3v.

Another difference is the framing used around some of the images, such as in the image for the Tree of Jesse. Yet another difference is that in the Mount Angel Kerver is that one of the later owners was perhaps practicing writing their signature on some of the folios. The Portland State Kerver does not contain any practice signatures within it.

These two incunabula printed by Kerver show how he grew as a printer. This can be seen in both the Portland State Kerver incunabulum which dates from 1507 as well as the Mount Angel Kerver incunabulum which dates from 1520.

• Written and researched by Chase Shepard, 2018 Medieval Portland Capstone Student