One end of the tube 44 is in {HEAD ~ communication} with {TAIL ~ a central portion} of the tube 45, and the other end of the tube 44 is formed with a gas supply hole 41 
with
One end of the tube 44 is in { HEAD ~ communication } with { TAIL ~ a central portion } of the tube 45 , and the other end of the tube 44 is formed with a gas supply hole 41
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 OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH