vertical line spacing of a markup

[Federico Bruni]

How can I adjust automatically the vertical spacing of a markup object?
The only solution I've found is using \line and \raise, but it's not a 
flexible solution.

See input below.

Thanks in advance,
Federico

\version "2.17.10"

% How can I change the vertical line spacing to make the lines closer?
\markup {
  \override #'(line-width . 40)
  \justify {
  text text text text text text text text text text text text
  text text text text text text text text text text text text
  text text text text text text text text text text text text
  text text text text text text text text text text text text
  }
}


% Horrible hack
\markup \column {
  \line { 1. text text text text text text text text text text }
  \raise #2
  \line { 2. text text text text text text text text text text }
  \raise #3
  \line { 3. text text text text text text text text text text }
  \raise #4
  \line { 4. text text text text text text text text text text }
}