{{explanation}}
On 2nd chord 2c+4c change sides (1,2x,3,4x)

1–
: 1W+2W & 3W+4W set to the other | change places RH ; Men repeat (2,1x,4,3x)
9–
: 2c+1c & 4c+3c RHA ; 1c+4c LHA, **while{4}** 2c+3c chase clw ½ round the set, at end all W face out (3,1x,4,2x)
17–
: 3c+1c & 4c+2c M-Chain
25–
: Circle8 and back