Also, it is to be noted that trailing surface 25 on each tooth need not be rectilinear; it may have {HEAD ~ a variety} of {TAIL ~ contours} as provided by the shape of grinding wheel 12 
of
Also , it is to be noted that trailing surface 25 on each tooth need not be rectilinear ; it may have { HEAD ~ a variety } of { TAIL ~ contours } as provided by the shape of grinding wheel 12
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH