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Phi. What is Prolation?
Ma. It is the measuring of Semibreves by Minims, and is either more or less. The more prolation is, when the Semibreve containeth three Minims, his signs be these: ʘ Ꞓ̇
A musical diagram shows the division of rhythmic values in more prolation. Nine minims are grouped into threes, each group connecting via brackets to a single semibreve. These are further grouped under two signs: a circle with a central dot and a half-circle with a central dot, each placed above a breve note.
The less prolation is when the Semibreve containeth but two Minims: The sign whereof is the absence of the prick thus. O C
A musical diagram shows less prolation. It illustrates the binary division of notes: groups of two minims connecting to semibreves. Above the notes are the signs for this prolation: a plain circle and a plain half-circle.
So that you may gather that the number doth signify the mode, the circle the time, and the presence or absence of the point the prolation. I have thought good for your further knowledge to set down before you the examples of all the Moods, joined to their times and prolations: to begin with the great Mood perfect. Here is his ensample following without any prolation, because in this Mood it is always *unperfect.
*Great Mood and time perfect.
A hierarchical musical diagram for Great Mood and time perfect shows 27 minims grouped by threes into 9 semibreves, then into 3 breves, resolving into a single long note. The sign "O 3" is printed below.
Great Mood unperfect and time perfect
The great Mood unperfect, with time perfect, is set down thus.
A hierarchical musical diagram for Great Mood unperfect, with time perfect, shows 12 minims grouped by threes into 4 semibreves, then into 2 breves, resolving into a single long note. The sign "C 3" is printed below.