1-8
: 1s Petronella turn into centre (2s step up), 1s+2s set to partners &
  1s+2s dance RH across. 1L faces Ladies' side
9-16
: 1L followed by 1M casts behind 2L, crosses over, casts behind 3M, dances
  up middle. 1s remain in centre, 1L facing out between 2M & 3M, 1M
  below 3s facing Ladies' side
17-24
: 1s+3s dance LH across, 1s+3s set & 1s dance Petronella turn to 2nd place
  opp sides
25-32
: 2s+1s+3s Adv (Bar 26: 1s quick 1/2 turn 2H) & Ret. 2s+1s+3s turn RH