Abstract
Natural gas was substituted for propane gas in the oxygen-fuel mixture supplying the Technicon AutoAnalyzer flame photometer. This was accomplished by the use of a 1/3-hp rotary pump and attached manifold, which compressed the gas from the city line and supplied it at a constant pressure to the burner module of the system. A method for the automatic analysis of serum Li was devised by using K as an internal standard and comparing the output of the Li-sensitive photo-cell with that of an attenuated K-sensitive cell. In addition, a simple procedure was incorporated into the routine determination of serum Na and K: samples of insufficient volume were diluted in a solution of known electrolyte concentration, which permitted their quantitation without changing the tubing manifold or other operating components of the system.