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