John Dygon's Proportiones practicabiles secundum Gaffurium Book

Containing two separate but very closely related texts on arithmetic proportions and their application in the rhythmic notation of polyphonic music, this slender and enigmatic manuscript of unmistakable English origin written in the first half of the sixteenth century (Cambridge, Trinity College, O.3.38) is now edited and translated for the first time. The redactor was the monk John Dygon, prior of St. Augustine's Monastery in Canterbury at the Dissolution and the holder of a bachelor's degree in music from the University of Oxford; but the treatises of the Cambridge manuscript, rather than presenting a new and independent treatment of proportions in polyphony, are in fact largely extracted and paraphrased from Book IV of the Practica musice of Franchinus Gaffurius, first printed in Milan in 1496. Replacing the musical examples of the celebrated Italian treatise with newly composed works, Dygon adapted Gaffurius's text to increase its relevance for English practitioners. As an item within the traditions of English theoretical writing at the end of the Middle Ages, the treatise represents a unique example of direct derivation from a single near-contemporaneous continental treatise, and as a source (though peripheral) for one of the major theoretical works of the period, the English book is significant on account of the amount of material that has been modified and adapted.