Yet let not artist whether new or old,

  Boast of his skill such wondrous works to make;

  But leave this feat to spell, wherewith controlled

  The spirits of the infernal bottom quake.

  The hall, whereof in other strain I told,

  With volume sacred to Avernus' lake,

  Or Norsine grot, throught subject Demons' might,

  Was made by Merlin in a single night.