What is "to dance on nothing"

Dance \Dance\ (d[.a]ns), v. i. [imp. & p. p. Danced; p. pr. & vb. n. Dancing.] [F. danser, fr. OHG. dans[=o]n to draw; akin to dinsan to draw, Goth. apinsan, and prob. from the same root (meaning to stretch) as E. thin. See Thin.]

1. To move with measured steps, or to a musical accompaniment; to go through, either alone or in company with others, with a regulated succession of movements, (commonly) to the sound of music; to trip or leap rhythmically.

   Jack shall pipe and Gill shall dance.
   --Wither.

   Good shepherd, what fair swain is this Which dances with your daughter?
   --Shak.

2. To move nimbly or merrily; to express pleasure by motion; to caper; to frisk; to skip about.

   Then, 'tis time to dance off.
   --Thackeray.

   More dances my rapt heart Than when I first my wedded mistress saw.
   --Shak.

   Shadows in the glassy waters dance.
   --Byron.

   Where rivulets dance their wayward round.
   --Wordsworth.

   To dance on a rope, or To dance on nothing, to be hanged.