{{explanation}}
Note: Music in 10 bar phrases

1-10
: 1s+3s set & dance 1/2 R&L (no polite turn), 3M+1L cross, dancing out
  between 2s **while** 3L+1M cross, dancing out between 4s & 1s & 3s 1/2
  turn partner LH back to place
11-20
: All set to partner, all dance 1/2 Grand Chain (1 bar/hand), all turn
  partner RH.  3 4 1 2
21-30
: 3s+1s set & dance 1/2 RH across, 2s+4s set & dance LH across, all set
31-40
: All dance Double Ladies' Chain with Ladies dancing 1/2 RH across in
  centre, Bars 37-38 all 1/2 turn LH into prom hold & dance
  anticlockwise 1 place round.  2 3 4 1