Mensural notation is the musical notation system used for polyphonic European vocal music from the late 13th century until the early 17th century. The term "mensural" refers to the notation of precise rhythmic durations based on numerical proportions of note values. Its modern name is derived from the terminology of medieval theorists, who used terms like musica mensurata ("measured music") or cantus mensurabilis ("measurable song") to refer to the rhythmically defined polyphonic music of their age, as opposed to musica plana or musica choralis, i.e., Gregorian plainchant. Mensural notation was employed principally for polyphonic vocal music, while plainchant retained the older system of neume notation throughout the period, and some instrumental music was written in various forms of instrument-specific tablature notation.
Mensural notation grew out of an earlier, more limited method of notating rhythms in terms of fixed repetitive patterns, called rhythmic modes, which were developed in France around 1200. An early form of mensural notation was described and codified in the treatise Ars cantus mensurabilis ("The art of measured chant") by Franco of Cologne (). An expanded system allowing for greater rhythmic complexity was introduced in France with the stylistic movement of the Ars nova in the 14th century, while Italian 14th-century music developed its own, somewhat different variant. Around 1400, the French system was adopted across Europe and became the standard form of notation for 15th- and 16th-century Renaissance music. Over the course of the 17th century, mensural notation gradually evolved into modern measure (or bar) notation.
The salient innovation of mensural notation was the systematic use of different note shapes for rhythmic durations, used in well-defined, hierarchical numerical relations to each other. This made note lengths less context-dependent than in the earlier rhythmic mode notation, but a note's length could be equal to either two or three units of the next smallest order. In modern notation, each type of note is equal to two units of the next smallest one, regardless of context. A note in mensural notation could be read as ternary ("perfect") or binary ("imperfect"), depending on rules of context and also on a system of mensuration signs comparable to modern time signatures. There was also a complex system of temporarily shifting note values by proportions such as 2:1 or 3:2. Mensural notation used no bar lines, and sometimes employed special connected note forms (ligatures) inherited from earlier medieval notation. Unlike in very early polyphonic music notation, and unlike in modern practice, mensural notation was not usually written in a musical score format, but rather in individual parts.
Mensural notation was extensively described and codified by contemporary theorists. As these writings, like all academic work of the time, were usually in Latin, many features of the system are still conventionally referred to by their Latin terms.
Note values +Note valuesNameCentury13th, 14th15th17thMaximaMx LongaL BrevisBSemibrevisSbMinimaMnSemiminimaSmFusaFSemifusaSf The system of note types used in mensural notation closely corresponds to the modern system. The mensural brevis is nominally the ancestor of the modern double whole note (breve); likewise, the semibrevis corresponds to the whole note (semibreve), the minima to the half note (minim), the semiminima to the quarter note (crotchet), and the fusa to the eighth note (quaver). Very rarely, mensural notation also used yet smaller subdivisions, such as the semifusa (corresponding to the sixteenth note or semiquaver). There were also two larger values, the longa (quadruple whole note or long) and the maxima (or duplex longa, called a large in Britain), which are no longer in regular use today.
Despite these nominal equivalences, each note had a much shorter temporal value than its modern counterpart. Between the 14th and 16th centuries, composers repeatedly introduced new note shapes for ever smaller temporal divisions of rhythm, and the older, longer notes were slowed down in proportion. The basic metrical relationship of a long to a short beat shifted from longa–breve in the 13th century, to breve–semibreve in the 14th, to semibreve–minim by the end of the 15th, and finally to minim–semiminim (i.e., half and quarter notes, or minim and crotchet) in modern notation. Thus, what was originally the shortest of all note values used, the semibreve, has become the longest note used routinely today, the whole note.
Originally, all notes were written in solid, filled-in form ("black notation"). In the mid-15th century, scribes began to use hollow note shapes ("white notation"), reserving black shapes only for the smallest note values. This change was probably motivated by the change from parchment to paper for the most common writing material, as paper was less suited to holding large dots of ink.Apel 1962: 93.
Rests +RestsValueMensuralModernMx or L or BSbMnSmFSf As with the notes, the shapes of the rest symbols in mensural notation are already similar to their modern descendants (with the smaller values being successively introduced in the course of the period of mensural notation). The rest symbols of the larger values had a clear visual logic reflecting their time durations, based on the breve rest being a vertical stroke the length of one staff space. For the longa rests, a visual distinction was made depending on whether the longa was imperfect (two breves long) or perfect. Accordingly, their signs were visually twice or three times the length of a breve rest respectively, while the semibreve rest was half that length. Maxima rests, in turn, were groups of two or three longa rests combined. If several longa rests followed each other, groups of either two or three of them were written together on the same staff line to indicate whether they were supposed to be grouped into perfect or imperfect maxima units. (The modern forms of the maxima and longa rests refer to their use in traditional multimeasure rests.)
Ligatures
+Binary ligaturesvalueproprietasperfectiodesc.asc.B–Lcum propr.cum perf.L–Lsine propr.cum perf.B–Bcum propr.sine perf.L–Bsine propr.sine perf.Sb–Sbcum opposita prop. +Generalized ligature rulesfinal Lfinal Binitial L initial Bnon-final LMaxima
Ligatures are groups of notes written together, usually indicating melismatic singing of the same syllable over several notes. Ligature forms exist only for the larger note values from the semibreve upwards. Their use in mensural notation was a holdover from the earlier modal rhythmic system, of which they inherited some of their rhythmic meaning.
The rhythmic values of ligatures in modal notation had been based on a metric reinterpretation of the ligature neumes used since much earlier in the notation of Gregorian plainchant. In modal notation, ligatures represented stereotyped rhythmic sequences of short and long notes, typically involving groups of one or more initial short notes (i.e., breves) and one final long note (i.e., a longa). In mensural notation, this rule was generalized, with all other rhythmic combinations being classified in terms of deviation from this basic pattern. In medieval terminology, a ligature possessed perfectio ("perfection")Note that the term "perfection" is here used in a different sense than that of the ternary versus binary note durations. Whether any breve or longa in a ligature was itself of perfect or imperfect duration was a matter independent of the ligature forms. if its final note was a longa (L), and it had proprietas ("propriety") if its first note was a breve (B).Eggebrecht 1991: 152f.
Accordingly, a note pair of B–L (cum proprietate et cum perfectione) could be written with the most basic of ligature shapes, those inherited from plainchant, namely the descending clivis () and the ascending podatus (). Likewise, three-note groups of B–B–L could be written with some of the inherited ternary neumes, such as the porrectus (, direction down–up), the torculus (, direction up–down), or the scandicus (, direction up–up).
If, by way of exception, the first note was to be a longa (sine proprietate), this was indicated by a reversal of initial stems: the descending clivis had its downward stem removed (), while, conversely, the ascending podatus had one added to it ( or ).
On the other hand, if the final note was to be a breve (sine perfectione), this was signaled by a change in the noteheads themselves: the descending sequence of square heads was replaced with a single diagonal beam (), while the ascending podatus had its second note unfolded to the right (). Both sequences correspond to the initial B–B segments of the ternary porrectus and torculus respectively.
If both exceptions concurred (sine proprietate et sine perfectione), the corresponding alterations were combined.
In addition to sequences of longa and breve, ligatures could also begin with pairs of semibreves (but not normally a single one).Apel 1962: 100 mentions some rare exceptions These were called cum opposita proprietate, and always marked by an upward-pointing stem to the left of the note pair.
There were also some alternate versions of the ascending ligatures. Thus, the basic ascending B–L podatus shape was replaced by one where the second note was both folded out to the right and marked with an extra stem (), as if these two modifications were meant to cancel each other out.Apel 1962: 96. The ascending L–L (sine proprietate) was modified accordingly.Some rare variants also existed for ascending ligatures with a final breve (sine perfectione), involving a reversed form of the descending oblique stroke, either with or without an initial stem (). However, contemporary theorists could not agree which of these two was supposed to be the B–B and which the L–B version (Apel 1962: 97).
Ligatures could contain any number of notes. In multi-note ligatures, the rules about initial and final values are applied in analogy to those in the binary forms. In addition, the following rules hold for notes in all positions:Apel 1962: 98.
Any notehead with an upward stem to its left is the first of a pair of semibreves (cum opposita proprietate). Any medial notehead with a downward stem to its right is a longa. A prolonged, double-width notehead with or without a downward stem to its right is a maxima. Any other notehead not covered by any of the rules above is a breve.
Mensurations
+Mensurations TernaryBinaryMaximodus perfectus1 Mx = 3 L imperfectus1 Mx = 2 LModus perfectus 1 L = 3 B imperfectus1 L = 2 BTempus perfectum1 B = 3 Sb imperfectum1 B = 2 SbProlatio maior1 Sb = 3 Mn minor1 Sb = 2 Mn
Mensural notation distinguished between several basic metric patterns of a piece of music, which were defined as combinations of ternary and binary subdivisions of time on successive hierarchical levels and roughly correspond to modern bar structures. The division of the semibreve into minims was called prolatio, that of the breve into semibreves was called tempus, and that of the longa into breves was known as modus. The division of the maxima into longas was called modus maximarum or modus maior; in the modern literature it is also sometimes called maximodus. Each of these levels could be either perfect (ternary) or imperfect (binary). The two types of prolatio were also known as "major prolation" and "minor prolation" respectively.
+Mensuration signsTempusProlatioSignSemibrevesMinimsModern1:41:21:1perfectummaiorperfectumminorimperfectummaiorimperfectumminor