{HEAD ~ The angle} formed between the intersection of first run 20 with second run 22 is, in {TAIL ~ the preferred embodiment}, a right angle 
in
{ HEAD ~ The angle } formed between the intersection of first run 20 with second run 22 is , in { TAIL ~ the preferred embodiment } , a right angle
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH