Quarter-comma meantone each kind, a perfect fifth of meantone contains four diatonic and three chromatic semitones, and an octave seven diatonic and five chromatic semitones, it follows that: Thus, in Pythagorean tuning, where sequences of just fifths (frequency ratio 3:2) and octaves are used to produce the other intervals, a whole tone is and a major third is An interval of a seventeenth, consisting of sixteen diatonic and twelve chromatic semitones, such as the interval from D to F, can be equivalently obtained using either This large interval of a seventeenth contains staff positions. In Pythagorean tuning, the size of a seventeenth
Octave (liturgy) Epistle and Gospel of the Feast are repeated again at the Divine Liturgy. The term "octave" is applied to some church observances that are not strictly liturgical. For example, many churches observe an annual "Octave of Prayer for Christian Unity", which runs from 18 January to 25 January. The octave was established in 1895 by Pope Leo XIII for the period between Ascension and Pentecost. In 1909, Pope Pius X approved the transfer of this octave to the period between the former feast of the Chair of St. Peter and the feast of the Conversion of St. Paul. In 1968,