The fluid assembly discharges the fluid to fill the cavity from a first position to a second position, the second position having an amount of a final volume such that {HEAD ~ a difference} between {TAIL ~ the known initial volume amount} and the final volume amount of the second position equals the volume of the body 
between
The fluid assembly discharges the fluid to fill the cavity from a first position to a second position , the second position having an amount of a final volume such that { HEAD ~ a difference } between { TAIL ~ the known initial volume amount } and the final volume amount of the second position equals the volume of the body
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 OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH