In FIG 6, {HEAD ~ the fabric gripping lines} are engaged upon {TAIL ~ the top piece} of fabric in the stack 
are engaged upon
In FIG 6 , { HEAD ~ the fabric gripping lines } are engaged upon { TAIL ~ the top piece } of fabric in the stack
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH