{{explanation}}
3s & 4s start on opp sides

1-8
: 2s & 3s set, 1/2 turn RH, 2s lead up, cross & cast to original
  places **while** 3s lead down, cross & cast to original places
9-16
: 1s+2s also 3s+4s dance double Fig of 8 (2s & 3s cross up/down to start)
17-24
: 1M+2M also 3M+4M turn LH 1.1/2 times **while** their partners turn
  similarly RH, 1s+4s dance 1/2 R&L (no polite turn)
25-32
: All dance RSh reels of 4 on sides with centre dancers ending with 1/2
  turn 2H into...
33-40
: All circle 8H round & back.  2 4 (1) (3)