{{explanation}}
Couples (M to left of W) form a big circle round the room, all face in

1–
: All M advance towards centre and retire ; in circle NHJ all slip 4 L
9–
: All W advance towards centre and retire ; in circle NHJ all slip 4 R and face P
17–
: G-Chain, 2 bars/hand
25–
: New couples M+W slip into centre {2}, out {2} ; turn P RH to form circle.