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