1–
: 1c slip down **while{4}** 4c (forming arch) slips up ; both C slip back, 1c making arch
9–
: 2M+3M & 2W+3W slip across (W arch) ; and back (M arch)
17–
: 1c leading all cast behind own line, 1c makes arch ; 2c+3c+4c dance up under arch (2,3,4,1)
25–
: All Circle8 and back