A third flow path, parallel to {HEAD ~ the first two flow paths}, may be provided with throttling apparatus for {TAIL ~ controlled communication} of fluid along such third flow path 
A third flow path , parallel to { HEAD ~ the first two flow paths } , may be provided with throttling apparatus for { TAIL ~ controlled communication } of fluid along such third flow path
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH