The frame substructure is situated substantially entirely on {HEAD ~ one side} of {TAIL ~ a perpendicular bisector} dropped from the shaft to a base  
of
The frame substructure is situated substantially entirely on { HEAD ~ one side } of { TAIL ~ a perpendicular bisector } dropped from the shaft to a base
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH