a pair of orifice plates, each said plate being disposed in a respective flow system between said clamping device and said reservoir to create {HEAD ~ a measurable pressure drop} in {TAIL ~ a fluid} passing therethrough 
in
a pair of orifice plates , each said plate being disposed in a respective flow system between said clamping device and said reservoir to create { HEAD ~ a measurable pressure drop } in { TAIL ~ a fluid } passing therethrough
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH