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