The material of construction of the grid walls of this invention is {HEAD ~ glass} with {TAIL ~ a high content} of lead oxide, or other high atomic number oxide 
with
The material of construction of the grid walls of this invention is { HEAD ~ glass } with { TAIL ~ a high content } of lead oxide , or other high atomic number oxide
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH