said plate member and said floor further cooperating to allow gas to seep from said compartment to said {HEAD ~ chamber} for providing {TAIL ~ a substantially uniform gaseous environment} in said chamber 
for providing
said plate member and said floor further cooperating to allow gas to seep from said compartment to said { HEAD ~ chamber } for providing { TAIL ~ a substantially uniform gaseous environment } in said chamber
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH