#(define-markup-list-command (fontsize-lines layout props increment args)
  (number? markup-list?)
   "Add @var{increment} to the font-size for markup lines.  Adjust baseline skip accordingly."
   (let ((entries (list
                   (cons 'baseline-skip (* 2 (magstep increment)))
                   (cons 'word-space (* 1 (magstep increment)))
                   (cons 'font-size increment))))
     (interpret-markup-list layout (cons entries props) args)))


\markuplines \fontsize-lines #-2
{
  \line { [TANTALUS and PELOPS are whispering loudly.] }
  \line { \italic { "PELOPS: " } Father, I must speak with you in confidence. }
  \line { \italic { "TANTALUS: " } Yes. }
  \wordwrap-lines { Long text Long text Long text Long text Long text  
      Long text Long text Long text Long text Long text Long text Long text  
      Long text Long text Long text Long text Long text Long text Long text  
      Long text Long text Long text Long text ends here }
  \line { \italic { "TANTALUS: " } Wow… that sux. }
}