Solesmes Notation
Various manuscripts and printed editions of Gregorian chant, using varying styles of square-note neumes, circulated throughout the Catholic Church for centuries. Some editions added rhythmic patterns, or meter, to the chants. In the 19th century the monks of the Benedictine abbey of Solesmes, particularly Dom Joseph Pothier (1835–1923) and Dom André Mocquereau (1849–1930) collected facsimiles of the earliest manuscripts and published them in a series of 12 publications called Paléographie musicale. They also assembled definitive versions of many of the chants, and developed a standardized form of the square-note notation which was adopted by the Catholic Church and is still in use in publications such as the Liber Usualis (although there are also published editions of this book in modern notation).
As a general rule, the notes of a single neume are never sung to more than one syllable; all three pitches of a three-note neume, for example, must all be sung on the same syllable. (This is not universally accepted; Richard Crocker has argued that in the special case of the early Aquitanian polyphony of the St. Martial school, neumes must have been "broken" between syllables to facilitate the coordination of parts.) However, a single syllable may be sung to so many notes that several neumes in succession are used to notate it. The single-note neumes indicate that only a single note corresponds to that syllable. Chants which primarily use single-note neumes are called syllabic; chants with typically one multi-note neume per syllable are called neumatic, and those with many neumes per syllable are called melismatic.
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