inlets for external supplies of {HEAD ~ inert gases} in {TAIL ~ the downward extending section} of the cylinder, 
inlets for external supplies of { HEAD ~ inert gases } in { TAIL ~ the downward extending section } of the cylinder ,
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH