{HEAD ~ A time switch} comprises {TAIL ~ terminals} spaced around a slip ring connected to a voltage source  
comprises
{ HEAD ~ A time switch } comprises { TAIL ~ terminals } spaced around a slip ring connected to a voltage source
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH