“…The complexing agent (EDTA) was infused at a constant rate, and the change in fluorescent intensity was continuously displayed on a chart recorder giving a curve from which the end-point of titration could be deduced (Klaus, 1962). The advantage of this method for the determination of small amounts of calcium is that it relies mainly on the constancy of the infusion rate and of the chart recorder speed; variations in the fluorescence or amplification do not matter since they are never so serious as to obscure the end-point.…”