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THE ART of DESCANT: OR Composing Musick in Parts.
PART II. Of Tones of Musick.
OF all things that belong to the making up of a Musician, the most necessary and useful one for him is the true knowledge of the Key or Mood, or Tone, for all signifie the same thing, with the Closes belonging un∣to it, for there is no Tune that can have any grace or sweetness unless it be bounden with∣in a proper Key, without running into strange Keys, which have no affinity with the Ayr of the Song. I have therefore thought good in an easie and brief discourse to endeavour to express that which many in large and obscure Volumes have made fearful to the idle Reader.
The first thing herein to be considered is the eighth, which is equally divided into a fourth, and a fifth, as thus: