a second coupling member for coupling {HEAD ~ said device carriage} to {TAIL ~ said shaft}; and, 
to
a second coupling member for coupling { HEAD ~ said device carriage } to { TAIL ~ said shaft } ; and ,
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH