This rare book appeared in 1935 to provide the complete verses for the Offertory chant in the Roman Rite of Mass, based on research into medieval manuscripts. These are not psalm-tone settings but through-composed melodies that add a beautiful dimension to the chant at this point in Mass. In his classic "Western Plainchant", David Hiley describes the ornate Offertory antiphons:

"The splendid offertories of the medieval Gregorian repertory are still among the best known of chants.... These [melismatic verses] are purely musical outpourings, where attention to the text is suspended and sheer joy in singing seems to take over, ecstatic and improvisatory."