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

1-8
: 2s+3s set, 2L followed by 2M casts down 1 place & dance LSh round 4M &
  up to 2nd place opp sides **while** 3L followed by 3M casts up & dance
  LSh round 1M to 3rd place own sides
9-12
: 2s+1L also 3s+4L dance RH across, 2s & 3s pass RSh as 1L & 4L dance out
  to place
13-16
: 2s+1M also 3s+4M dance LH across all back to original places, 1M, 4M, 2L
  & 3L face out
17-20
: 1M followed by partner casts down, across set to 3rd place opp
  sides **while** 4M casts up, across set to 2nd place own side

: Bars 17-18: 2L dances out/up to 1st place own side, Bars 19-20: 2M steps
  in/up to 1st place own side

: Bars 17-18: 3L dances out/down to 4th place Men's side, Bars 19-20: 3M
  steps in/down to 4th place Ladies' side
21-24
: 2s+4s also 1s+3s turn RH on sides
25-32
: All circle 8H round & back.  2 4(1)(3)