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