b) means for providing {HEAD ~ a first fluid stream} within said conduit together with a second fluid stream within said {TAIL ~ conduit} 
b ) means for providing { HEAD ~ a first fluid stream } within said conduit together with a second fluid stream within said { TAIL ~ conduit }
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL