an arm carrying said dip ring at a first point and mounted for movement about {HEAD ~ a first axis} passing through {TAIL ~ said arm} at a second point 
passing through
an arm carrying said dip ring at a first point and mounted for movement about { HEAD ~ a first axis } passing through { TAIL ~ said arm } at a second point
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH