factor in the theory of measur able music- was the color of the notes. The ordinary note was black. In the fourteenth cen tury a red note (notula rubra) was used. Origi nally this red note was used instead of signa tures to denote a change from perfcrtio to im perfectio or vice versa. Soon it was definitely used to indicate imperfeetio only. For want of red color, it was often left open or white (notula alba), and during the fifteenth century the white note had the same meaning as the red note of the fourteenth. When finally the white notes were generally adopted (during the sixteenth and seventeenth centuries), imperfectio was denoted by the black note (notula The time-value of the different notes as fixed by these signs or signatures was known as the integer valor notaram. But these fundamental values could be changed by means of a ugmenta Ito, diminatio, and proport io. Dimin ut to reduced the value of the notes in triple time to one-third, in duple time to one-half of the original value. It was indicated by a. vertical line through the signature (I) , or by a number to the tempos sign 2, or Q 3. Time indicated thus always denoted a lively tempo. eorrespondin,g to the modern allegro. Augment atio signified the restoration of the integer rotor of notes reduced by dimina 1 io. It was indicated by writing the ' ordinary sign of the integer ralor (1) ( . A change of the integer ruler by means of fractions was known as proportio. Thus T meant that the
time was to be accelerated, so that three breves now had the same duration as one breve of in teger valor. But -1- meant the opposite, viz. that the time was to be retarded. so that one breve now had the same duration as three breves of the integer color. A special kind of proportio was A group of two or more notes to be sung on one syllable was called ligature.. When only two notes were given to one syllable. they were written as one and called figura obligati.
In ligatures of more than two notes the time value of the individual notes was not deter mined from their actual shape hut from their position. The value of the first note could be a breve or a long. In the former ease the term proprirtas, in the latter improprietms, was ap plied. If the second note was lower than the first, proprict,rs was indicated by a vertical line (cauda) downward on the left side of the first note : ; if the second note was higher, the eanda was wanting, .77' . In both eases the first note is breve. Improprieta8 was indicated by adding the eauda to the first note if the sec ond was higher, and omitting it if the second was lower: Here both first notes are longs.
Out of this system of notation our modern system of notation has been gradually evolved. Those interested are referred to the comprehen sive histories of music and cycloRedias of Ger ber, Ambros, Coussemaker. See McsicAL NOTA