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

1-8
: All set, 1s turn RH, cross down to 2nd place, cast up to top & dance in
  to face down with nearer hands joined **while** 2s cross RH, cast up,
  cross down to own side & join 1s in a line across (2s facing
  up) **while** 3s cross RH, cast down, cross up to original sides &
  join 4s in a line across (3s facing down) **while** 4 turn RH, lead up
  to 3rd place crossing to other side, cast to 4th place & turn to face
  up with nearer hands joined
9-16
: All set in line, 1/2 turn to bring outside persons into centre, set &
  1/2 turn back to lines
17-24
: 1s & 4s (prom hold) dance RSh reels of 3 across set (1s with 2s & 4s
  with 3s)
25-32
: 1s & 4s (prom hold) dance down to bottom/up to top (Men passing LSh),
  drop RH, cross & cast to 2nd/3rd place then cross RH. 2 4(1)(3)