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