As the string continues to vibrate in this complex way, it also vibrates in eighths, producing the twenty-second, the C three octaves above tenor C. This is the eighth partial or harmonic, and the seventh overtone.
If you were to play tenor C at the organ and pull a 1-foot stop only, you would hear the twenty-second, the C three octaves above tenor C.
1' stops are octave-sounding stops, which sound the note at some octave above or below the key being played.
NOTE: We skipped the seventh partial. It corresponds to a very rare organ stop, so it is not discussed here.