A Dictionary of Music and Musicians/Octave (organ stop)

OCTAVE, or PRINCIPAL. An open metal cylindrical organ-stop, of four feet on the manual and eight feet on the pedal; the scale and strength of tone of which are determined by those of the open diapason on the same department. Where there are two Principals the second one is sometimes of wood, open, as at Christ's Hospital, when it partakes of the flute character. In the Temple organ the two stops, of metal, are called 'Octave' and 'Principal' respectively; the former being scaled and voiced to go with the new open diapason, and the latter to produce the first over-tone to the old diapason. In foreign organs the Octave stop sounds the first octave above the largest metal Register of Principal (Diapason) measure on the clavier; and is therefore of eight, four, or two feet size according to circumstances. [See Principal.] [App. p.734 "Add that an explanation of the term 'Short Octave' will be found in vol. ii. p. 588, and vol. iii. p. 653."]

[ E. J. H. ]