1-8
: 1s dance down the middle to 4th place **while** 4s cast up to 1st place.
  Repeat with 1s casting up & 4s dancing down the middle to finish in
  original places.
9-12
: 2s & 3s set advancing & turn right about to finish BtoB in the centre,
  facing diagonally towards end couples. (2s face 1s & 3s face 4s).All
  set.
13-16
: All turn opposite person (2L+1L also 3M+4M RH, 2M+1M also 3L+4L LH) (2s
  & 3s dance between end couples to turn) to finish 2L with partner
  behind, between 1s at the top & 3M (partner behind) between 4s at the
  bottom
17-24
: 2L followed by 2M cast off round 1M, behind men's line into 4th place on
  own sides **while** 3M followed by 3L casts up round 4L, behind
  Ladies' side into 1st place own sides. On bars 19-20 1s step down, 4s
  step up. All set  3 1 4 2
25-32
: 1s+4s dance round partners, RSh to RSh for 4 bars ending on side lines
  ready to chase clockwise 4 places. 3 1 4 2