first coil means for electromagnetically sensing relative proximity and left and right displacement of {HEAD ~ said projectile} in {TAIL ~ terms} of currents induced by the mechanical motion of said projectile 
in
first coil means for electromagnetically sensing relative proximity and left and right displacement of { HEAD ~ said projectile } in { TAIL ~ terms } of currents induced by the mechanical motion of said projectile
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 OTH