Juan was taught from out the best edition,
       Expurgated by learnéd men, who place
  Judiciously, from out the schoolboy's vision,
       The grosser parts; but, fearful to deface
  Too much their modest bard by this omission,
       And pitying sore his mutilated case,
  They only add them all in an appendix,
  Which saves, in fact, the trouble of an index.