{HEAD ~ The south pole} on tooth 1 is allowed to decay, the diminution occurring at a rate depending on the hysteresis of {TAIL ~ the rotor material} 
{ HEAD ~ The south pole } on tooth 1 is allowed to decay , the diminution occurring at a rate depending on the hysteresis of { TAIL ~ the rotor material }
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL