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

1-8
: 2s & 3s petronella turn as 1s & 4s cast in 1 place, all set in 2 diamond
  formations; 1s+2s also 3s+4s dance RH across (1s+4s return to original
  places as 2s+3s end BtoB facing out)
9-16
: 1s+2s also 3s+4s dance double Figs of 8 starting with 1s & 4s dancing
  between 2s & 3s, 2s & 3s 1/2 turn RH to face each other (L on Man's R)
17-24
: 2s+3s set & pass opp couple LSh to change places, 1s+3s also 2s+4s
  circle 4H round to left & turn partner 2H to face nearer end
25-32
: 1s+3s dance Allemande up as 2s+4s dance Allemande down to end 3 1 (4)
  (2)