1–
: 1c turn RH | cast off (2c up) ; 1c+1cnrs &frac12; diagonal R&L
9–
: 1c+4cnrs &frac12; diagonal R&L (3x,1,2x) ; 1c petronella to midline | set as H&G{2} to face 1cnrs
17–
: *Half Diamond Reel of Four:*  
  17–18: 1c & 1cnrs pass RSh, 1c end in 1cnr pos, 1cnrs pass LSh & turn to face each other on 2diag  
  19–20: 1c & 1cnrs set, 1cnrs advancing on [20] to end BtoB facing 3cnr pos  
  21–22: 1cnrs & 1c pass RSh, 1cnrs end in places as at [5], 1c pass LSh & turn to face P in 2plx  
  23–24: 1c set as H&G{2} to face 2cnrs  
25–
: Repeat [17–22] with 2cnrs, 1c end facing P up/down | 1c petronella to own sides (2,1,3)