1-8
: 1s & 2s petronella turn into middle (Ladies face down & Men up), set &
  dance 1/2 reel of 4 up & down the middle
9-16
: 2s & 1s set & petronella turn onto own sides, 2s+1s+3s Adv+Ret
17-24
: 1L dances RH across with 2s & 1M with 3s, 1s turn LH 1.1/2 times to face
  1st corner person as 2s & 3s chase cl'wise 1/2 way round
25-32
: 1s dance 1/2 diagonal reel of with 1st corners, passing RSh dance 1/2
  reel with 2nd corners 1s end in 2nd places