Ramsay
note by 2/4; and by the law of duplication, the law of the octave interval, a note which is a fifth below the note by 1/4, by 2/4, or by 1, the integer, i.e., the whole string. [Scientific Basis and Build of Music, page 76]
See Also
11.16 - Indig Numbers and the Power of the Powers of Two
Laws of Music
octave