means responsive to {HEAD ~ the reciprocable means} for generating {TAIL ~ pulses} in response to increments of movement of the reciprocable means 
for generating
means responsive to { HEAD ~ the reciprocable means } for generating { TAIL ~ pulses } in response to increments of movement of the reciprocable means
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH