Cam surfaces on the advancing elements, which engage cam surfaces on adjacent members in conjunction with a pair of pneumatic cylinders which apply a reciprocating motion thereto, provide {HEAD ~ the movement} of {TAIL ~ these advancing elements} 
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Cam surfaces on the advancing elements , which engage cam surfaces on adjacent members in conjunction with a pair of pneumatic cylinders which apply a reciprocating motion thereto , provide { HEAD ~ the movement } of { TAIL ~ these advancing elements }
OTH OTH OTH OTH OTH OTH OTH OTH 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 TAIL TAIL