In its closed condition, the abutment structure is capable of receiving a forcible impulse by {HEAD ~ an implement}, such as an iron, advancing along {TAIL ~ the upper surface} of the seaming board 
advancing along
In its closed condition , the abutment structure is capable of receiving a forcible impulse by { HEAD ~ an implement } , such as an iron , advancing along { TAIL ~ the upper surface } of the seaming board
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH