{HEAD ~ a second rail} situated along the opposite side of said work surface from {TAIL ~ said first rail}, wherein said first and second rails are oriented parallel to one another 
{ HEAD ~ a second rail } situated along the opposite side of said work surface from { TAIL ~ said first rail } , wherein said first and second rails are oriented parallel to one another
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH