The hot water in the tank is maintained at a constant level so that {HEAD ~ the quantity} of {TAIL ~ water} discharged by the dipper is fixed 
of
The hot water in the tank is maintained at a constant level so that { HEAD ~ the quantity } of { TAIL ~ water } discharged by the dipper is fixed
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH