Note that the carriage can move past the support members 19 to {TAIL ~ a position} at the left hand end of {HEAD ~ the beam} 
Note that the carriage can move past the support members 19 to { TAIL ~ a position } at the left hand end of { HEAD ~ the beam }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD