The method 14 which includes {HEAD ~ the steps} of determining at least first and second points on said screen, using {TAIL ~ said first point} to determine the location of said first spiral path and using said second point to determine the location of said second spiral path 
The method 14 which includes { HEAD ~ the steps } of determining at least first and second points on said screen , using { TAIL ~ said first point } to determine the location of said first spiral path and using said second point to determine the location of said second spiral path
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH