If one is the octave of the other a figure of 8 may be described, and so on.
In the Anglican Church Ascension Day and its octave continue to be observed as a great festival, for which a special preface to the consecration prayer in the communion service is provided, as in the case of Christmas, Easter, Whitsunday, and Trinity Sunday.
This was to demand a great sacrifice, but Octave Feuillet cheerfully obeyed the summons.
Musicians with treble lutes and with harps an octave lower (or with lutes and harps over the sopranos and tenors respectively) were to lead the singers in giving out the melody.
Festival of the instruments of the Passion, of the Precious Blood, of the invention and elevation of the Cross; all festivals of apostles, except those above noted; festivals of martyrs; masses for a papal election; the Feast of the Holy Innocents, when it falls on a Sunday (violet if on a week-day), and its octave (always red).
In works on sound it is usual to adopt Helmholtz's notation, in which the octave from bass to middle C is written c d e f g a b c'.
This story is much amplified in the account given by St John of Damascus in the homilies In dormitionem Mariae, which are still read in the Roman Church as the lesson during the octave of the feast.
The next octave above has two accents, and each succeeding octave another accent.
We shall treat only of the diatonic scale, which is the basis of European music, and is approximated to as closely as is consistent with convenience of construction in key-board instruments, such as the piano, where the eight white notes beginning with C and ending with C an octave higher may be taken as representing the scale with C as the key-note.
But obviously in either the octave or the fifth, if the tuning is imperfect, beats occur all along the line wherever the tones should coincide with perfect tuning.