FIG 3 shows the arm 12 in {HEAD ~ an intermediate position} in which the lengths of {TAIL ~ the two cords} 57 are identical 
FIG 3 shows the arm 12 in { HEAD ~ an intermediate position } in which the lengths of { TAIL ~ the two cords } 57 are identical
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH