Almost forty years ago, Richard Crocker published two monumental volumes titled The Early Medieval Sequence (University of California Press, 1977), focusing largely on the work of Notker Balbulus, a ninth-century monk known as one of the leading literary figures of his time. About thirty years earlier, in 1948, Wolfram von den Steinen published Notker der Dichter und seine geistige Welt, another monumental edition of what was deemed the authentic works of the monk of St Gall who died in 912. So one might ask the question: "Why in this light might a new edition of the Liber hymnorum be considered desirable?" This is precisely the question Calvin Bower, professor emeritus at the University of Notre Dame, poses in the introduction to the first of his two volumes published almost seventy years after von den Steinen's work. His answer is based on those long melodies the young Notker wrote about in the Dedicatio to his Liber: "When I was still a young man and the very long melodies repeatedly committed to memory escaped my fickle little heart, I began quietly to contemplate how I might somehow tie them down" (Dedicatio 7-8, p. 1).

Bower's edition fills in the gaps in von den Steinen's edition, where reference is made to only one short example of music in over six hundred pages of text. While there are citations to editions of the melodies, the poetic texts are not accompanied by the very melodies that generated them. This seems justification enough for Bower's monumental work. Because the resulting two-volume edition containing Notker's collection of texts and their melodies was of such quality and of such importance to medieval scholars, the American Musicological Society saw fit to bestow upon Bower the 2017 Claude V. Palisca Award. This award honors "a scholarly edition or translation in the field of musicology published during the previous year in any language and in any country by a scholar who is a member of the AMS or a citizen or permanent resident of Canada or the United States, deemed by a committee of scholars to best exemplify the highest qualities of originality, interpretation, logic and clarity of thought, and communication." In addition to Crocker and von den Steinen, Bower credits Susan Rankin and others whose earlier work on Notker pollinated his own. He admits to having been inspired and even taught by his graduate students at the University of North Carolina, in particular Lance Brunner, who completed a dissertation on "The Sequences of Verona Capitolare CVII and the Italian Sequence Tradition" in 1977 (vii).

In a brief biographical sketch, Bower clarifies that this Notker has been known by modern scholars as the monk of St. Gall and by his own description as Notker Balbulus. In his Gesta Karoli Magni ("The Deeds of Charles the Great"), a series of didactic anecdotes he wrote for Charles the Fat, the great-grandson of Charlemagne who visited Saint Gall in 883, the monk described himself as a "stammerer and toothless" (balbus et edentulous). Bower distinguishes this Notker from others from later periods: Notker medicus who died in 975 and Notker Labeo, the translator of Boethius and other Latin works from Latin to German who died in 1022 (2).

In his prologue or dedicatio as Bower prefers to call it, Notker Balbulus admits to having difficulty remembering melodiae longissimae, most likely sequence melodies. Sequences were derived from alleluia melodies and, as the story goes, a monk arrived from Jumièges with a book containing sequence melodies fitted with texts that Notker believed were in need of editing. He set about the task of rewriting a number of the texts as well as composing original ones. Notker's teachers guided him in the process and arranged for the collection to be copied onto rolls for the purpose of teaching the choirboys at the monastery.

Following a description of the genesis of Notker's Versus, as he referred to them, Bower examines the formation of the Liber ymnorum explaining the meaning of the term ymnus and dealing with question of authorship. He cites examples of Notker's brand of humor and describes his use of language as "distinctly Notkerian," arguing for the importance of the collection standing "as a monument to Notker's creative powers." (25). Bower reveals how Notker's "concept of versus is grounded in Bede's discussion of rhythmic poetry" (26) wherein "fixed accentual powers correspond with basic patterns of melodic gestures." (27) In Part II, "The Liber ymnorum as a Musical and Poetic Document," Bower's methodology in illustrating the notation is clear and accessible and not too technical for those lacking knowledge of chant. His section on the manuscript sources of the East Frankish Sequence and Notker's Liber builds on earlier research and corrects ambiguities and inaccuracies in previous source studies. The complete Liber with neumatic and modern musical notation and critical notes completes the first volume.

Volume II includes a detailed commentary with text and translation for each of the 49 Versus in the collection, vocabulary for all words used in the Liber, indices of proper nouns and adjectives, divine names and ymni and prosae by incipit. Sandwiched in between the indices is a general bibliography that includes the manuscripts containing Notker's Ymni from the primary sources through the tenth-, eleventh- and twelfth-century exemplars. Missing is a general index which would have been helpful for a number of reasons, although this omission does not detract from the stunning erudition of Bower's work on the craft of Notker Balbulus, the poet, author and teacher who was able to overcome a rather severe disability to become an arbiter of refined taste in setting mnemonic poetry to music.