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