{TAIL ~ load pressure transducer} means for measuring the pressure in the supply line between the restrictor and {HEAD ~ the pressure sensor} and providing an output signal indicative thereof which is supplied to the control means; and 
{ TAIL ~ load pressure transducer } means for measuring the pressure in the supply line between the restrictor and { HEAD ~ the pressure sensor } and providing an output signal indicative thereof which is supplied to the control means ; and
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH