Iron filings 58 are sprinkled around {HEAD ~ the L} shaped rod 30 and toroid magnets 42 and 44 to illustrate {TAIL ~ the modification effect} of the magnetic lines of force 
Iron filings 58 are sprinkled around { HEAD ~ the L } shaped rod 30 and toroid magnets 42 and 44 to illustrate { TAIL ~ the modification effect } of the magnetic lines of force
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH