Bowmore 22 Year Old The Octave Duncan Taylor is a limited-edition, age-statement Islay single malt whisky produced at the Bowmore Distillery. The Octave range showcases independent bottler Duncan Taylor`s expertise in selecting old, rare single malts for special attention. Octave casks are about one-eighth of the size of a conventional whisky cask, yielding just 80 or so bottles. This Bowmore 22-year-old was drawn from single cask (#3737529) at a natural strength of 53.7%.