{{explanation}}
Square set - 5s in centre facing 1s

1-8
: 1s+5s+3s dance parallel RSh reels of 3 up/down set (1s+5s pass RSh to
  start)
9-16
: 5s dance up between 1s, divide & cast round 1s to meet in centre &
  turn 1.1/4 RH (or birl) to face 2s
17-24
: 2s+5s+4s dance parallel RSh reels across (2s+5s pass RSh to start)
25-32
: 5s dance out between 2s, divide & cast round 2s to meet in centre &
  turn 1.3/4 RH (or birl) to face 1s
33-40
: 5s+1s dance 1/2 RH across, 1s+4s repeat, 4s+3s repeat, 3s+2s repeat. 2s
  now in centre facing new 1s ready to repeat