Reference numeral 47 denotes an adjusting knob adapted to adjust {TAIL ~ the downward pressure} applied to {HEAD ~ the upper feed dog} 40 
Reference numeral 47 denotes an adjusting knob adapted to adjust { TAIL ~ the downward pressure } applied to { HEAD ~ the upper feed dog } 40
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH